299 results on '"Ganio LM"'
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2. Interannual radial growth response of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) to severe droughts: an analysis along a gradient of soil properties and rooting characteristics.
- Author
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Spangenberg, Göran, Zimmermann, Reiner, Küppers, Manfred, Schäffer, Jürgen, and Hein, Sebastian
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DOUGLAS fir ,CLAY soils ,DROUGHT tolerance ,DROUGHTS ,SOIL texture ,NORWAY spruce - Abstract
Key message: We analyzed stem growth responses of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) to severe drought in 2003/04 and 2018. The results showed high drought tolerance in sandy, loamy, and most silty soils, with limitations on clayey soils. This study indicates the susceptibility of Douglas-firs with shallow root systems to extreme drought and the importance of deep rooting for high drought resilience. Context: Although Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) is considered a more drought-tolerant substitute for Norway spruce (Picea abies (L.) Karst.) in Europe, there is considerable uncertainty about the drought tolerance of Douglas-fir under climate change, specifically concerning soil properties. Aims: This study aimed to assess the influence of soil texture, plant-available water capacity, and rooting characteristics on the interannual stem growth response of Douglas-fir when exposed to severe drought. Methods: Along a soil texture gradient from sand to clay, we selected seven closely spaced sites at elevations of approximately 500 m a.s.l. in southern Germany. Mixed-effects models were used to analyze the effects of soil physical and rooting characteristics on growth response indices (resistance, recovery, resilience) related to the severe to extreme droughts in 2003/04 and 2018. Results: Douglas-fir showed high drought tolerance in sandy, loamy, and most silty soils. However, the results suggest a higher drought stress risk on clayey soils, as well as at specific silty sites with shallow root systems. A higher effective rooting depth increased the resilience of Douglas-fir during the extreme drought in 2018. Conclusion: Douglas-fir demonstrated its drought tolerance in most soil textures. In addition, this study supports the need for combined above- and below-ground investigations on factors influencing drought tolerance and the importance of rooting for drought resilience. [ABSTRACT FROM AUTHOR] more...
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- 2024
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3. Linking crown fire likelihood with post-fire spectral variability in Mediterranean fire-prone ecosystems.
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Fernández-Guisuraga, José Manuel, Calvo, Leonor, Quintano, Carmen, Fernández-Manso, Alfonso, and Fernandes, Paulo M.
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FIRE management ,BROADLEAF forests ,FUEL reduction (Wildfire prevention) ,BEHAVIORAL assessment ,CONIFEROUS forests ,TREE mortality ,RANDOM forest algorithms ,CONIFERS ,DEAD trees - Abstract
Background: Fire behaviour assessments of past wildfire events have major implications for anticipating post-fire ecosystem responses and fuel treatments to mitigate extreme fire behaviour of subsequent wildfires. Aims: This study evaluates for the first time the potential of remote sensing techniques to provide explicit estimates of fire type (surface fire, intermittent crown fire, and continuous crown fire) in Mediterranean ecosystems. Methods: Random Forest classification was used to assess the capability of spectral indices and multiple endmember spectral mixture analysis (MESMA) image fractions (char, photosynthetic vegetation, non-photosynthetic vegetation) retrieved from Sentinel-2 data to predict fire type across four large wildfires Key results: MESMA fraction images procured more accurate fire type estimates in broadleaf and conifer forests than spectral indices, without remarkable confusion among fire types. High crown fire likelihood in conifer and broadleaf forests was linked to a post-fire MESMA char fractional cover of about 0.8, providing a direct physical interpretation. Conclusions: Intrinsic biophysical characteristics such as the fractional cover of char retrieved from sub-pixel techniques with physical basis are accurate to assess fire type given the direct physical interpretation. Implications: MESMA may be leveraged by land managers to determine fire type across large areas, but further validation with field data is advised. Satellite products with a direct physical meaning were accurate for estimating fire behaviour (surface fire, intermittent crown fire, and continuous crown fire) of past wildfire events across large burned Mediterranean ecosystems. This has major implications for anticipating post-fire ecosystem responses (e.g. delayed tree mortality). [ABSTRACT FROM AUTHOR] more...
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- 2024
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4. Fuel types misrepresent forest structure and composition in interior British Columbia: a way forward.
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Baron, Jennifer N., Hessburg, Paul F., Parisien, Marc-André, Greene, Gregory A., Gergel, Sarah. E., and Daniels, Lori D.
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FOREST surveys ,FUEL reduction (Wildfire prevention) ,WILDFIRE prevention ,OPERATIONS management ,FUEL systems ,FIRE management - Abstract
Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
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- 2024
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5. Characterizing Non-governmental Organizations And Local Government Collaborations In Urban Forest Management Across Canada.
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Doucet, Tyler C., Duinker, Peter N., Charles, John D., Steenberg, James W. N., and Zurba, Melanie
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NONGOVERNMENTAL organizations ,FOREST management ,COMMUNITY organization ,LOCAL government ,MUNICIPAL government - Abstract
Urban forests are being threatened by rapid urbanization, biodiversity crises, and climate variability. In response, governments are increasingly collaborating with the public for solutions to these mounting challenges. Non-governmental organizations (NGOs) are dominant players in these collaborations because of their ability to supplement governments' expertize and resources and bring social and ecological issues to the forefront of civic agendas. Despite their growing visibility in urban forest management, there is a lack of attention directed to the forms and range of NGO relationships. This study focuses on addressing this gap and examining collaborations between local governments and NGOs in urban forest programming by characterizing their components including mandates, relationship ties, accountability, resource exchange, and power dynamics. We collected data using semi-structured interviews with three groups: leaders of NGOs, municipal government officials in an urban forest or public works departments, and urban-forest experts who have observed their interactions. The participants represent 32 individuals in nine Canadian cities. Our results indicate that NGO-government collaborations have relational ties and accountability processes that are both formal and informal in nature. Formality in collaborations is often associated with the amount of funding, proximity to government, or size of the NGO. In addition, our findings suggest that NGOs present an opportunity for local governments to supplement their resources and capacity. While the strength and formality of collaborations may be a product of NGO size and budgets, public servants should not hesitate to engage smaller, grassroots NGOs to realize their public service mandates. Characterizing the components of these governance processes provides a benchmark for practitioners participating in similar public-civic interactions and arms them with the knowledge to navigate collaborative decision-making. [ABSTRACT FROM AUTHOR] more...
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- 2024
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6. Forestry in the Face of Global Change: Results of a Global Survey of Professionals.
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Himes, Austin, Bauhus, Jürgen, Adhikari, Shankar, Barik, Saroj Kanta, Brown, Hugh, Brunner, Andreas, Burton, Philip J., Coll, Lluís, D'Amato, Anthony W., Diaci, Jurij, Dorji, Yonten, Foli, Ernest G., Ganz, David J., Hall, Jefferson S., Keenan, Rodney, Lu, Yuanchang, Messier, Christian, Munanura, Ian, Piotto, Daniel, and Seifert, Thomas more...
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- 2023
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7. Application of the class-balancing strategies with bootstrapping for fitting logistic regression models for post-fire tree mortality in South Korea.
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Hwang, Kyungrok, Kang, Wonseok, and Jung, Yugyeong
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TREE mortality ,REGRESSION analysis ,LOGISTIC regression analysis ,STANDARD deviations ,DEAD trees ,RED pine - Abstract
We aimed to tackle a common problem in post-fire tree mortality where the number of trees that survived surpasses the number of dead trees. Here, we investigated the factors that affect Korean red pine (Pinus densiflora Siebold & Zucc.) tree mortality following fires and assessed the statistical effects of class-balancing methods when fitting logistic regression models for predicting tree mortality using empirical bootstrapping (B = 100,000). We found that Slope, Aspect, Height, and Crown Ratio potentially impacted tree mortality, whereas the bark scorch index (BSI) and diameter at breast height (DBH) significantly affected tree mortality when fitting a logistic regression with the original dataset. The same variables included in the fitted logistic regression model were observed using the class-balancing regimes. Unlike the imbalanced scenario, lower variabilities of the estimated parameters in the logistic models were found in balanced data. In addition, class-balancing scenarios increased the prediction capabilities, showing reduced root mean squared error (RMSE) and improved model accuracy. However, we observed various levels of effectiveness of the class-balancing scenarios on our post-fire tree mortality data. We still suggest a thorough investigation of the minority class, but class-balancing scenarios, especially oversampling strategies, are appropriate for developing parsimonious models to predict tree mortality following fires. [ABSTRACT FROM AUTHOR] more...
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- 2023
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8. Surviving in Changing Forests: Abiotic Disturbance Legacy Effects on Arthropod Communities of Temperate Forests.
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Cours, J., Bouget, C., Barsoum, N., Horák, J., Le Souchu, E., Leverkus, A. B., Pincebourde, S., Thorn, S., and Sallé, A.
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- 2023
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9. Climate influences on future fire severity: a synthesis of climate-fire interactions and impacts on fire regimes, high-severity fire, and forests in the western United States.
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Wasserman, Tzeidle N. and Mueller, Stephanie E.
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FOREST fires ,FUEL reduction (Wildfire prevention) ,FIRE management ,FOREST regeneration ,FOREST resilience ,FIRE weather ,PRESCRIBED burning ,FOREST conversion - Abstract
Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
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- 2023
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10. Integrating plant physiology into simulation of fire behavior and effects.
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Dickman, L. Turin, Jonko, Alexandra K., Linn, Rodman R., Altintas, Ilkay, Atchley, Adam L., Bär, Andreas, Collins, Adam D., Dupuy, Jean‐Luc, Gallagher, Michael R., Hiers, J. Kevin, Hoffman, Chad M., Hood, Sharon M., Hurteau, Matthew D., Jolly, W. Matt, Josephson, Alexander, Loudermilk, E. Louise, Ma, Wu, Michaletz, Sean T., Nolan, Rachael H., and O'Brien, Joseph J. more...
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DROUGHT management ,HEAT of combustion ,VEGETATION dynamics ,PLANT-water relationships ,HIGH temperatures ,MODELS & modelmaking - Abstract
Summary: Wildfires are a global crisis, but current fire models fail to capture vegetation response to changing climate. With drought and elevated temperature increasing the importance of vegetation dynamics to fire behavior, and the advent of next generation models capable of capturing increasingly complex physical processes, we provide a renewed focus on representation of woody vegetation in fire models. Currently, the most advanced representations of fire behavior and biophysical fire effects are found in distinct classes of fine‐scale models and do not capture variation in live fuel (i.e. living plant) properties. We demonstrate that plant water and carbon dynamics, which influence combustion and heat transfer into the plant and often dictate plant survival, provide the mechanistic linkage between fire behavior and effects. Our conceptual framework linking remotely sensed estimates of plant water and carbon to fine‐scale models of fire behavior and effects could be a critical first step toward improving the fidelity of the coarse scale models that are now relied upon for global fire forecasting. This process‐based approach will be essential to capturing the influence of physiological responses to drought and warming on live fuel conditions, strengthening the science needed to guide fire managers in an uncertain future. [ABSTRACT FROM AUTHOR] more...
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- 2023
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11. Comparison of in vitro Antifungal Activity Methods Using Extract of Chitinase-producing Aeromonas sp. BHC02.
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Cadirci, Bilge Hilal and Yilmaz, Gulesme
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ANTIFUNGAL agents ,FUNGAL diseases of plants ,AEROMONAS ,FUNGAL cell walls ,ALTERNARIA alternata ,FUSARIUM solani ,CHITINASE - Abstract
Biological control to prevent fungal plant diseases offers an alternative approach to facilitate sustainable agriculture. Since the chitin in fungal cell walls is a target for biocontrol agents, chitinases are one of the important antifungal molecules. In this study, the aim was to investigate a new chitinase isolated from a fluvial soil bacterium and to show the antifungal activity of the characterized chitinase by comparing the three common methods. The bacterium with the highest chitinase activity was identified as Aeromonas sp. by 16 S rRNA sequence analysis. Following the determination of the optimum enzyme production time, the enzyme was partially purified, and the physicochemical parameters of the enzyme were investigated. In the antifungal studies, direct Aeromonas sp. BHC02 cells or partially purified chitinase were used. As a result, in the first method in which the Aeromonas sp. BHC02 cells were spread on the surface of petri dishes, no zone formation was observed around the test fungi spotted on the surface. However, zone formation was observed in the methods in which the antifungal activity was investigated using the partially purified chitinase enzyme. For example, in the second method, the enzyme was spread on the surface of PDA, and zone formation was observed only around Penicillum species among the test fungi spotted on the surface. In the third method, in which the necessary time was given for the formation of mycelium of the test fungi, it was observed that the growth of Fusarium solani, Alternaria alternata and Botrytis cinerea was inhibited by the partially purified chitinase. This study concludes that the results of the antifungal activities depend on the method used and all fungal chitins cannot be degraded with one strain's chitinase. Depending on the variety of chitin, some fungi can be more resistant. [ABSTRACT FROM AUTHOR] more...
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- 2023
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12. A novel post-fire method to estimate individual tree crown scorch height and volume using simple RPAS-derived data.
- Author
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Arkin, Jeremy, Coops, Nicholas C., Daniels, Lori D., and Plowright, Andrew
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CROWNS (Botany) ,FIRE management ,COST analysis ,POINT cloud ,TREE height - Abstract
Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
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- 2023
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13. Tree spatial pattern and mortality prediction in burned patches of Dahurian larch (Larix gmelinii Rupr.) forest that experienced a mixed-severity wildfire.
- Author
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Zhang, Jili, Shu, Lifu, Wang, Mingyu, Wei, Rui, Wang, Lizhong, Wang, Shuo, and Yang, Guang
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TREE mortality ,CONIFEROUS forests ,LARCHES ,FOREST dynamics ,FIRE management ,MORTALITY ,WILDFIRE prevention ,DEAD trees ,PINACEAE - Abstract
Background: Fire-caused tree mortality and spatial pattern are crucial for evaluating forest dynamics and developing management prescriptions. Aims: We investigated direct fire effects on spatial distribution and mortality of Dahurian larch (Larix gmelinii Rupr.) and assessed the Ryan and Amman (R–A) model performance and the importance of immediate mortality predictors. Methods: We analysed spatial patterns of fire-killed and surviving trees of three size classes in plots that burned at low- to high-severity using pair-correlation functions and tree mortality with the R–A model and generalised linear mixed models. Key results: The mixed-severity fire caused strong density-dependent mortality and more aggregated surviving tree patterns at short distances. The R–A model generally performed acceptably, and crown scorch and bole char height were critical predictors determining post-fire tree mortality. Conclusions: Fire-caused tree mortality and spatial patterns are controlled primarily by spatial variation in tree size and biological and structural characteristics. The prediction biases of the R–A model arose primarily from the intrinsic traits of Dahurian larch and the imbalanced dataset. Fine-scale neighbourhood density might be a fundamental priority for fire management and restoration. Implications: This study could possibly improve mechanistic understanding of spatial pattern development and tree mortality in similar fire-prone conifer forests. A larch-dominated forest exhibited density-dependent post-fire mortality patterns at short distances and increased aggregation among surviving trees post-fire. A widely used USA tree mortality model performed acceptably for this species. This study could potentially inform management strategies for conifer forests with similar structures and fire regimes. [ABSTRACT FROM AUTHOR] more...
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- 2023
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14. Adapting reforestation programs to observed and projected climate change.
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Sang, Zihaohan, Hamann, Andreas, and Rweyongeza, Deogratias
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Reforestation programs generally rely on locally collected seed, which is assumed to be adapted to local climate conditions. To adapt to a changing climate, current methods of choosing reforestation seed should be revised to align seed movement with the magnitude and direction of climate change. In a case study for the province of Alberta, Canada, we analyzed options for seed transfer in white spruce (Picea glauca (Moench) Voss) based on the growth of more than 1000 white spruce genotypes spanning about 40 years of field testing. We used multivariate statistics with nine climate variables to match seed source and planting site climates to improve tree growth under the past and expected future climate conditions. We found that seed transfers can improve growth in some cases. However, the climate change vector does not always align with geographic gradients, which makes finding well-adapted seed sources difficult or impossible. This issue may partially be addressed by relying on additional silvicultural adaptation options to address climate change. Our case study provides a methodological template of how jurisdictions can determine the feasibility as well as magnitude and direction of assisted migration prescriptions to adapt their reforestation programs to new planting environments. [ABSTRACT FROM AUTHOR] more...
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- 2023
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15. Evaluation of rock mass permeability along a borehole by integrating the techniques of geological features and logistic regression: a case study in Taiwan.
- Author
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Hsu, Shih-Meng, Liao, Yi-Fan, and Dong, Ming-Chia
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GEOLOGICAL modeling ,LOGISTIC regression analysis ,ROCK permeability ,BOREHOLES ,HYDRAULIC conductivity ,PREDICTION models - Abstract
When the budget for in situ hydraulic tests is constrained, cost-effective approaches for determining the variations in hydraulic conductivity along a borehole remain enticing for helping design and planning of groundwater-related engineering systems. This study proposes a practical method with probabilistic outputs for fulfilling engineering concerns. First, 474 sets of hydrogeological investigation and hydraulic test data of fractured rock masses in most of the watersheds of mountainous areas of Taiwan were collected. Then, seven geological indices [rock quality design (RQD), depth index (DI), gouge content design (GCD), lithology permeability index (LPI), fracture density (FD), fracture width (FW), and groundwater velocity (GV)] significantly correlated with rock mass permeability were identified. Third, using logistic regression analysis, the seven indices were used as explanatory variables, and the hydraulic conductivity was utilized as an outcome variable (its threshold value is 1 × 10
−6 m/s) for developing prediction models of high groundwater potential zones along a borehole. All indices passed the collinearity test, indicating no collinearity between the indices. To make the prediction models proposed more flexible in practical applications, a total of 127 combinations based on the combination selection of seven explanatory variables were explored to develop various prediction models. Through the validation of the Hosmer–Lemeshow test, Omnibus test, and Wald test for all developed models, only 77 models were statistically significant. The 77 models were evaluated by three measures of Nagelkerke R2 , SR (success rate), and AUC (area under the curve) to further understand the prediction performance of each model. The results show that the accuracy of the prediction model is positively correlated with the number of geological indices used. When all seven geological indices are used, Nagelkerke R2 , SR, and AUC can reach the best values, which are 0.83, 91.6%, and 0.976, respectively. In conclusion, the prediction model developed by combining geological indices with logistic regression analysis can provide a more efficient way of understanding the hydrogeological conditions of a borehole site. [ABSTRACT FROM AUTHOR] more...- Published
- 2023
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16. Trends in western USA fire fuels using historical data and modeling.
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Boisramé, Gabrielle F. S., Brown, Timothy J., and Bachelet, Dominique M.
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FUEL reduction (Wildfire prevention) ,FIREFIGHTING ,DATA modeling ,IMPACT loads ,FOREST surveys ,MODEL validation ,CLIMATE change - Abstract
Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
- Published
- 2022
- Full Text
- View/download PDF
17. Genetic variation in fire recovery and other fire-related traits in a global eucalypt species.
- Author
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Hernández, Mariano A., Butler, Jakob B., Ammitzboll, Hans, Freeman, Jules S., O'Reilly-Wapstra, Julianne, Vaillancourt, René E., and Potts, Brad M.
- Subjects
GENETIC variation ,LOCUS (Genetics) ,EUCALYPTUS ,SPECIES ,EUCALYPTUS globulus ,TREE size - Abstract
To understand the potential of forests to adapt to wildfire, we studied the genetic architecture of fire-related structural, damage and recovery traits in a globally important Australian forest tree species, Eucalyptus globulus. Fourteen traits were evaluated in an outcrossed F
2 population in a field trial in Tasmania, Australia, which was burnt by a wildfire 14 years after planting. The trial also included open-pollinated families of the grandparental dwarf and tall ecotypes used to produce the F2 population. We studied the phenotypic correlations within the F2 population and performed quantitative trait loci (QTL) analyses using a linkage map comprised of 472 markers. Ecotype comparisons revealed that almost all traits were under genetic control, with trees of the dwarf ecotype significantly more damaged and mainly recovering from lignotubers, whereas tall ecotype trees mainly recovered from epicormic resprouts extending for a variable height up the stem. Within the F2 , tree size was negatively correlated with fire damage and positively correlated with recovery. Genetic control of fire-related traits was confirmed by the detection of 38 QTL in the F2 population. These QTL accounted for 4 to 43% of the phenotypic variation in these traits. Several QTL co-located and likely reflect pleiotropic effects. However, many independent QTL were detected, including QTL for crown consumption and trunk scorch, epicormic resprouting, resprout herbivory, and seedling establishment. The QTL detected argue that many genetically controlled mechanisms are responsible for variation in fire damage and recovery. [ABSTRACT FROM AUTHOR] more...- Published
- 2022
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18. Hydrological response of a paired watershed to rainfall storm events in arid region: a study in Dehgin of Hormozgan province, Iran.
- Author
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Mohamadi, Sedigheh and Bagheri, Reza
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RAINSTORMS ,WATERSHED management ,ARID regions ,WATERSHEDS ,CLIMATE change ,RAINFALL ,DISCHARGE coefficient - Abstract
Influenced by global climate change, rainfall characteristics have changed in recent years, especially in arid regions. However, the actual response of the watersheds' hydrological indicators to erosive rainfalls has not been understood yet. Therefore, this study sought to investigate the changes in the watersheds' hydrological response due to the intra-rainfall indices of various events in the Dehgin paired watershed in Hormozgan, Iran, using the data collected from 2007 to 2019. To this end, first, all rainfall events which elicited the response of watersheds were identified concurrently based on the meteorological and flume data. Then, the qualitative and quantitative intra-storm variations associated with hydrological indicators (i.e., total runoff and discharge variables) were extracted for statistical analysis. The study's results revealed that (1) the increasing rates of the continuous discharge time of the control and treatment watershed's front position were about 2.25 and 4.76 times the rear position, respectively. (2) A strong linear relationship was found between total runoff volume and variables including precipitation of storm and time to storm peak in both control and treatment watersheds, with the R
2 reported to be 67.7 and 63.6%, respectively. (3) It was also found that the watershed management operations reduced the variables' values including the maximum discharge, the discharge variation coefficient, continuity time of discharge, the peak of the time to discharge, the number of discharge peaks, and the total runoff volume by 3, 1.6, 2.25, 2.37, 2.42, and 3.27 times, respectively. Therefore, it could conceivably be argued that extreme rainfalls can be controlled by management practices in the watersheds. [ABSTRACT FROM AUTHOR] more...- Published
- 2022
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19. Extreme drought conditions increase variability of nitrate through a stream network, with limited influence on the spatial patterns of stream phosphate.
- Author
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Warren, Dana R., Pett-Ridge, Julie C., Segura, Catalina, Kaylor, Matthew J., and Heaston, Emily D.
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DROUGHT management ,DROUGHTS ,NITRATES ,PHOSPHATES ,HYDROLOGY - Abstract
Nutrient availability is an important control on ecosystem processes in streams. In this study, we explored how an extreme summer drought affected spatial patterns of nutrient availability along a fourth-order stream network in western Oregon. Droughts are expected to become increasingly common and more severe across western North America and around the world. Understanding how nutrient availability changes locally and throughout a stream network during low-flow periods provides important insight into drought impacts on stream ecosystems. We quantified nitrate (NO
3 − ) and phosphate (PO4 3− ) concentrations every 50 m along 11.5 km of a headwater stream network during three summer periods of different drought intensity that encompassed some of the lowest discharges observed in this system over its 70-year hydrologic record. Semi-variogram analysis indicated that concentrations of the dominant limiting nutrient, NO3 − , became increasingly spatially heterogenous during the most extreme drought conditions, whereas spatial variability of PO4 3− concentrations remained similar across all three flows. Synoptic sampling during the most severe low-flow period revealed hotspots of biogeochemical processing that would be missed if sampling were conducted during higher flows when surface water dilution and more rapid transport of limiting nutrients would dampen local signals. Along a 3 km section of the upper mainstem, an increase in N availability during the drought led to a reduction in the degree of N-limitation and a potential shift toward P-limitation. Our results suggest that projected climate-induced changes in hydrology in this region will modify local nutrient availability. [ABSTRACT FROM AUTHOR] more...- Published
- 2022
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20. Forest and Freshwater Ecosystem Responses to Climate Change and Variability at US LTER Sites.
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Campbell, John L, Driscoll, Charles T, Jones, Julia A, Boose, Emery R, Dugan, Hilary A, Groffman, Peter M, Jackson, C Rhett, Jones, Jeremy B, Juday, Glenn P, Lottig, Noah R, Penaluna, Brooke E, Ruess, Roger W, Suding, Katharine, Thompson, Jonathan R, and Zimmerman, Jess K more...
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CLIMATE change ,NUTRIENT cycles ,FRESH water ,FOREST microclimatology ,ATMOSPHERIC temperature ,ECOSYSTEMS - Abstract
Forest and freshwater ecosystems are tightly linked and together provide important ecosystem services, but climate change is affecting their species composition, structure, and function. Research at nine US Long Term Ecological Research sites reveals complex interactions and cascading effects of climate change, some of which feed back into the climate system. Air temperature has increased at all sites, and those in the Northeast have become wetter, whereas sites in the Northwest and Alaska have become slightly drier. These changes have altered streamflow and affected ecosystem processes, including primary production, carbon storage, water and nutrient cycling, and community dynamics. At some sites, the direct effects of climate change are the dominant driver altering ecosystems, whereas at other sites indirect effects or disturbances and stressors unrelated to climate change are more important. Long-term studies are critical for understanding the impacts of climate change on forest and freshwater ecosystems. [ABSTRACT FROM AUTHOR] more...
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- 2022
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21. Factors controlling the spatial distribution of soil organic carbon in the Chinese medicine producing area of NW China.
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Mingzhu He, Liang Tang, Chengyi Li, and Jianxin Ren
- Abstract
Soil organic carbon is an important factor for the cultivation and production of traditional Chinese medicine. This study aimed to reveal the spatial distribution of the soil organic carbon density (SOCD) and the effects of the climatic and topographic factors in Longxi County (Gansu Province, China). The soil organic carbon (SOC) from 200 sampling points were collected and analyzed in 2018. Results showed that the total SOCD was 26.7 ± 10.2Mg ha
-1 , while the SOCDs at a soil depth of 0-10, 10-30, and 30-50 cm were 6.3 ± 1.7, 11.0 ± 3.8, and 9.3 ± 4.8 Mg ha-1 , respectively. The temperature, precipitation, elevation, and stream power index showed significant correlations with the SOCD at each soil layer. With an increasing soil depth, the correlation between the slope, relief amplitude, surface roughness, and SOCD gradually decreased. From the central plains to the mountainous areas, the SOCD increased with rising elevation, while the valley plain that formed by the river basin showed low levels of SOCD. Therefore, the scientificmanagement of soil fertility and the development of precision agriculture, combined in a soil testing fertilization formula, will guarantee the healthy development of the Chinese herbal medicine planting. [ABSTRACT FROM AUTHOR] more...- Published
- 2022
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22. Gaining Insights about Forest Health Prescriptions from Loggers and Foresters: Understudied Voices in the Human Dimensions of Forest Health.
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Snyder, Stephanie A., Blinn, Charles R., Roth, Sarah, and Windmuller-Campione, Marcella
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FOREST health ,HUMAN voice ,LOGGERS ,FORESTERS ,BLACK spruce - Abstract
Maintaining healthy forests requires multiple individuals, including foresters who develop timber sale silvicultural prescriptions and loggers who implement those prescriptions, resulting in the transplantation of forest health science into workable management plans. However, data on the experiences, attitudes, and opinions of these two groups are often missing when developing or refining forest health treatment strategies. To explore the role that these groups play in sustaining forest health, we examined timber sale administrators' and loggers' perspectives on treatment approaches for eastern spruce dwarf mistletoe (Arceuthobium pusillum) (ESDM), a parasitic plant native to Minnesota that increases mortality and reduces growth rate and regeneration success of black spruce (Picea mariana). While ESDM has been managed for decades in black spruce stands in Minnesota, little is known about the effectiveness of the management approaches. Data were gathered through interviews and focus groups with loggers, as well as an online survey and focus groups with foresters who administer timber sales. Study participants identified a range of field-based barriers, knowledge gaps, and uncertainties that hamper the ability to effectively implement ESDM treatment strategies as designed, including financial, administrative, informational, policy-related, and environmental factors. These factors have a significant bearing on the ability to effectively implement ESDM treatment approaches; yet may be factors that were not known or considered when developing treatment strategies. This case study underscores the value of nurturing a science–management partnership to ensure that a broad set of voices are considered when developing or revising forest health treatment strategies. [ABSTRACT FROM AUTHOR] more...
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- 2022
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23. Save a Tree and Save a Life: Estimating the Health Benefits of Urban Forests.
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Tan, Bing Yang
- Subjects
URBAN forestry ,CARDIOVASCULAR disease related mortality ,TREE mortality ,EMERALD ash borer ,URBAN health ,BORERS (Insects) ,URBAN trees - Abstract
Do trees in urban areas benefit human health? More than 100 million Americans live in large cities, yet little is known about the health benefits of the trees they live with. I provide causal evidence on the elasticity of air pollution and mortality to urban forest loss from the exogenous introduction of the emerald ash borer insect to the continental United States. Trees benefit urban health by reducing pollution; dieback that affects up to 5.8% of city forests is associated with increases in mean PM2.5 levels that reach 4.4%. Damage to city forests ultimately leads to excess deaths of up to 1.8%; much of this increase is driven by increases in cardiovascular and respiratory disease mortality. If the estimated median elasticity of all-cause mortality to tree damage of − 0.42 is extrapolated to all forests in the urban continental United States, my results imply urban forests reduced all-cause mortality by 29.3%, or 299,000 deaths total, in 2014. [ABSTRACT FROM AUTHOR] more...
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- 2022
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24. The interactions among fire, logging, and climate change have sprung a landscape trap in Victoria's montane ash forests.
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Lindenmayer, David B., Bowd, Elle J., Taylor, Chris, and Likens, Gene E.
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MOUNTAIN forests ,SPRING ,CLIMATE change ,LOGGING ,LANDSCAPES ,FOREST fires ,FIRE management ,WILDFIRE prevention - Abstract
Ecosystems are influenced by multiple drivers, which shape ecosystem state and biodiversity. In some ecosystems, interactions and feedbacks among drivers can produce traps that confine an ecosystem to a particular state or condition and influence processes like succession. A range of traps has been recognized, with one of these – "a landscape trap" first proposed a decade ago for the tall, wet Mountain Ash and Alpine Ash forests of Victoria, south-eastern Australia. Under such a trap, young flammable forest is at high risk of reburning at high severity, thereby precluding stand maturation, and potentially leading to ecosystem collapse. These young forests are more common because recurrent wildfire and widespread clearcutting have transformed historical patterns of forest cover from widespread old-growth with small patches of regrowth embedded within it, to the reverse. Indeed, approximately 99% of the montane ash ecosystem is now relatively young forest. Based on new empirical insights, we argue that at least three key inter-related pre-conditions underpin the development of a landscape trap in montane ash forests. A landscape trap has been sprung in these forests because the pre-conditions for its development have been met. We show how inter-relationships among these pre-conditions, leading to frequent high-severity fire, interacts with life history attributes (e.g., time to viable seed production) to make montane ash forests (e.g., which have been highly disturbed through logging and frequent fire) vulnerable to ecosystem collapse. We conclude with the ecological and resource management implications of this landscape trap and discuss how the problems created might be rectified. [ABSTRACT FROM AUTHOR] more...
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- 2022
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25. Impact of transgenic insect-resistant maize HGK60 with Cry1Ah gene on community components and biodiversity of arthropods in the fields.
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Chen, Yanjun, Ren, Mengyun, Pan, Libo, Liu, Bo, Guan, Xiao, and Tao, Jun
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TRANSGENIC organisms ,TRANSGENIC plants ,ARTHROPODA ,NUMBERS of species ,BIODIVERSITY ,CORN - Abstract
In recent years, transgenic technology has developed rapidly, but the risk of the environmental release of transgenic organisms is still a key issue. Research on the impact on biodiversity is an effective way to objectively evaluate the risk. By taking transgenic maize HGK60 with insect-resistant gene Cry1Ah and common maize Zheng 58 as control, a 2-year experiment of arthropod community biodiversity in fields of them were studied using three methods.in 2019 and 2020. The results showed that a total of 124 species and 38537 individuals were observed from the experiment, belonging to 11 orders and 40 families. There was no significant difference in the individual number and species number of herbivorous, predatory and parasitic groups in the two kinds of maize in two years. Only the individual number of HGK60 was significantly higher than that of common maize Zheng 58 at heading stage in 2019. And the percentages of individual number and species number in different groups were basically the same in the two kinds of maize at each stage in two years. Analyses of Richness index, Shannon-Wiener diversity index, Dominance index and Evenness index showed no significant difference between the two kinds of maize in two years. The similarity coefficient of the arthropod community suggested that the arthropod community composition of HGK60 was similar to that of common maize Zheng 58. Furthermore, HGK60 had no significant effect on the relative stability of the arthropod community. These results indicated that despite the presence of a relatively minor difference in arthropod community between the two kinds of maize, the planting of HGK60 had little effect on arthropod community biodiversity. The results provided some data and support for the further studies of environmental risk of transgenic crops. [ABSTRACT FROM AUTHOR] more...
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- 2022
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26. Trait phenology and fire seasonality co‐drive seasonal variation in fire effects on tree crowns.
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Bison, Nicole N., Partelli‐Feltrin, Raquel, and Michaletz, Sean T.
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CROWNS (Botany) ,PHENOLOGY ,SEASONS ,PHOTOSYNTHETIC rates ,ATMOSPHERIC temperature - Abstract
Summary: The plume of hot gases rising above a wildfire can heat and kill the buds in tree crowns. This can reduce leaf area and rates of photosynthesis, growth, and reproduction, and may ultimately lead to mortality. These effects vary seasonally, but the mechanisms governing this seasonality are not well understood.A trait‐based physical model combining buoyant plume and energy budget theories shows the seasonality of bud necrosis height may originate from temporal variation in climate, fire behaviour, and/or bud functional traits. To assess the relative importance of these drivers, we parameterized the model with time‐series data for air temperature, fireline intensity, and bud traits from Pinus contorta, Picea glauca, and Populus tremuloides.Air temperature, fireline intensity, and bud traits all varied significantly through time, causing significant seasonal variation in predicted necrosis height. Bud traits and fireline intensity explained almost all the variation in necrosis height, with air temperature explaining relatively minor amounts of variation.The seasonality of fire effects on tree crowns appears to originate from seasonal variation in functional traits and fire behaviour. Our approach and results provide needed insight into the physical mechanisms linking environmental variation to plant performance via functional traits. [ABSTRACT FROM AUTHOR] more...
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- 2022
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27. Effect of rainbow trout introductions on food webs in lakes of the arid Patagonia.
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Porcel, Sol, Fogel, Marilyn L., Izaguirre, Irina, Roesler, Ignacio, and Lancelotti, Julio L.
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RAINBOW trout ,FOOD chains ,AMPHIPODA ,STABLE isotope analysis ,LAKES ,WATER birds ,LITTORAL zone - Abstract
Rainbow trout have been stocked in naturally fishless lakes in the reproductive area of the endangered Hooded Grebe, an endemic aquatic bird of Southern Patagonia. The effects of trout introduction were proposed as one of the potential causes of their critical situation. Trout could modify the trophic structure of the aquatic community by altering the trophic relationships of stocked lakes. Changes in the spatial distribution and/or diet of the Grebe's main prey, which is dominated by amphipods, could affect their trophic position, and introduce the use of alternative carbon sources. We compared the food webs between fishless and stocked lakes using stable isotope analysis and associated community metrics. Results provided evidence that the presence of fish influences the food web structure of the studied communities. Stocked lakes showed higher values of δ
15 N compared to fishless ones. Community metrics estimation described an increase in trophic redundancy in stocked lakes, which could be explained by the high degree of trout omnivory. Additionally, the study found changes in use of carbon sources in amphipods between stocked and fishless lakes. The spatial distribution of the amphipods toward littoral zone of the stocked lakes, as an anti-predatory response, could impact the Hooded Grebe. [ABSTRACT FROM AUTHOR] more...- Published
- 2022
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28. Ten simple rules for getting started with statistics in graduate school.
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Zitomer, Rachel A., Karr, Jessica, Kerstens, Mark, Perry, Lindsey, Ruth, Kayla, Adrean, Lindsay, Austin, Suzanne, Cornelius, Jamie, Dachenhaus, Jonathan, Dinkins, Jonathan, Harrington, Alan, Kim, Hankyu, Owens, Terrah, Revekant, Claire, Schroeder, Vanessa, Sink, Chelsea, Valente, Jonathon J., Woodis, Ethan, and Rivers, James W. more...
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GRADUATE education ,SCIENTIFIC knowledge ,SCIENTIFIC literature ,DATA entry ,STATISTICS ,STATISTICAL hypothesis testing ,STATISTICAL power analysis - Abstract
Ten simple rules for tackling your first mathematical models: A guide for graduate students by graduate students. Graduate school is often a time of enormous professional growth, and for many students, it is the first time they receive advanced training in statistics. Regardless of whether one uses R or another programming language (e.g., SAS, Python), the work that new graduate students put into learning programming early in graduate school will pay dividends later as they move beyond graduate school and into the next phase of their career. [Extracted from the article] more...
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- 2022
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29. Limitations to Propagule Dispersal Will Constrain Postfire Recovery of Plants and Fungi in Western Coniferous Forests.
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Gill, Nathan S, Turner, Monica G, Brown, Carissa D, Glassman, Sydney I, Haire, Sandra L, Hansen, Winslow D, Pansing, Elizabeth R, Clair, Samuel B St, and Tomback, Diana F
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CONIFEROUS forests ,PLANT-fungus relationships ,FOREST conversion ,DISPERSAL (Ecology) ,FOREST fire ecology ,COMMUNITY forests ,FUNGAL spores ,TUNNEL ventilation - Abstract
Many forest species are adapted to long-interval, high-severity fires, but the intervals between severe fires are decreasing with changes in climate, land use, and biological invasions. Although the effects of changing fire regimes on some important recovery processes have previously been considered, the consequences for the dispersal of propagules (plant seeds and fungal spores) in forest communities have not. We characterize three mechanisms by which changing fire regimes disrupt propagule dispersal in mesic temperate, boreal, and high-elevation forests: reduced abundance and altered spatial distributions of propagule source populations, less effective dispersal of propagules by wind, and altered behavior of animal dispersers and propagule predators. We consider how disruptions to propagule dispersal may interact with other factors that are also influenced by fire regime change, potentially increasing risk of forest conversion. Finally, we highlight urgent research topics regarding how dispersal limitation may shape twenty-first century forest recovery after stand-replacing fire. [ABSTRACT FROM AUTHOR] more...
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- 2022
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30. Differences in branch hydraulic architecture related to the aridity of growing sites and seed sources of coastal Douglas-fir saplings.
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Lachenbruch, Barbara, Clair, J Bradley St., and Harrington, Constance A
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SEED technology ,WATER gardens ,WOOD density ,FOREST microclimatology ,LEAF area ,EFFECT of herbicides on plants - Abstract
To better understand hydraulic adaptations of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) to local climate, we examined genetic (G) and environmental (E) responses of branch hydraulic architecture of 7-year-old saplings from dry and wet climates of origin grown at a relatively dry and a relatively wet common garden site in western Oregon. We sampled 2 years of branch growth from three dry-source and three wet-source families grown at both sites (72 branches, total). Overall, only 4 of the 11 traits had significant genetic (G) effects, whereas 9 traits had significant environmental (E) effects (P < 0.05). Both dry and wet sources had higher leaf-specific conductance (k
l ) at the dry than the wet site, but the values were achieved by different mechanisms and driven by G × E effects for leaf area/sapwood area (Al / As ), shoot length (L), specific conductivity (Ks ) and leaf-specific conductivity (Kl ). Dry sources achieved higher kl in the dry site through higher Kl (via a lower Al / As and no change in Ks ) with no difference in L. Wet sources achieved higher kl at the dry site through no difference in Kl (via no effect on Al / As , despite decreases in Al and As , and lower Ks ) with lower L. Vulnerability to embolism (measured as percentage loss of conductivity at 4 MPa) had no G effect but an E effect, with slightly lower values at the dry site. Specific leaf area had G and E effects, with lower values for the dry sources and site. There were no G or E effects on wood density. The different responses of dry and wet sources to site aridity suggest that populations are differentially adapted to the aridity of growing sites. Population variation in response to aridity should be considered when selecting seed sources for establishing forests for future climates. [ABSTRACT FROM AUTHOR] more...- Published
- 2022
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31. Spatial analysis of G.f.fuscipes abundance in Uganda using Poisson and Zero-Inflated Poisson regression models.
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Mugenyi, Albert, Muhanguzi, Dennis, Hendrickx, Guy, Nicolas, Gaëlle, Waiswa, Charles, Torr, Steve, Welburn, Susan Christina, and Atkinson, Peter M.
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POISSON regression ,REGRESSION analysis ,AFRICAN trypanosomiasis ,TSETSE-flies ,VECTOR data - Abstract
Background: Tsetse flies are the major vectors of human trypanosomiasis of the form Trypanosoma brucei rhodesiense and T.b.gambiense. They are widely spread across the sub-Saharan Africa and rendering a lot of challenges to both human and animal health. This stresses effective agricultural production and productivity in Africa. Delimiting the extent and magnitude of tsetse coverage has been a challenge over decades due to limited resources and unsatisfactory technology. In a bid to overcome these limitations, this study attempted to explore modelling skills that can be applied to spatially estimate tsetse abundance in the country using limited tsetse data and a set of remote-sensed environmental variables. Methodology: Entomological data for the period 2008–2018 as used in the model were obtained from various sources and systematically assembled using a structured protocol. Data harmonisation for the purposes of responsiveness and matching was carried out. The key tool for tsetse trapping was itemized as pyramidal trap in many instances and biconical trap in others. Based on the spatially explicit assembled data, we ran two regression models; standard Poisson and Zero-Inflated Poisson (ZIP), to explore the associations between tsetse abundance in Uganda and several environmental and climatic covariates. The covariate data were constituted largely by satellite sensor data in form of meteorological and vegetation surrogates in association with elevation and land cover data. We finally used the Zero-Inflated Poisson (ZIP) regression model to predict tsetse abundance due to its superiority over the standard Poisson after model fitting and testing using the Vuong Non-Nested statistic. Results: A total of 1,187 tsetse sampling points were identified and considered as representative for the country. The model results indicated the significance and level of responsiveness of each covariate in influencing tsetse abundance across the study area. Woodland vegetation, elevation, temperature, rainfall, and dry season normalised difference vegetation index (NDVI) were important in determining tsetse abundance and spatial distribution at varied scales. The resultant prediction map shows scaled tsetse abundance with estimated fitted numbers ranging from 0 to 59 flies per trap per day (FTD). Tsetse abundance was found to be largest at low elevations, in areas of high vegetative activity, in game parks, forests and shrubs during the dry season. There was very limited responsiveness of selected predictors to tsetse abundance during the wet season, matching the known fact that tsetse disperse most significantly during wet season. Conclusions: A methodology was advanced to enable compilation of entomological data for 10 years, which supported the generation of tsetse abundance maps for Uganda through modelling. Our findings indicate the spatial distribution of the G. f. fuscipes as; low 0–5 FTD (48%), medium 5.1–35 FTD (18%) and high 35.1–60 FTD (34%) grounded on seasonality. This approach, amidst entomological data shortages due to limited resources and absence of expertise, can be adopted to enable mapping of the vector to provide better decision support towards designing and implementing targeted tsetse and tsetse-transmitted African trypanosomiasis control strategies. Author summary: Tsetse flies are the major vectors of human and animal trypanosomiasis. To support control efforts, there is need to understand the location of these vectors in terms of distribution and abundance. Due to limited resources and unsatisfactory technology, delimiting the extent and magnitude of tsetse coverage remains a challenge. In a bid to overcome these limitations, this study attempted to explore modelling skills that can be applied to inform decision makers about the status of tsetse abundance using limited historical tsetse data and a set of remote-sensed environmental variables. Two regression models; standard Poisson and Zero-Inflated Poisson (ZIP) were fitted and evaluated for superiority. The results indicated the level of responsiveness of each covariate in influencing the vector across the study area. Tsetse abundance was found to be largest at low elevations in areas of high vegetative activity, in game parks, forests and permanently flooded shrubs during the dry season. This approach can be adopted to enable mapping of any tsetse species to provide better decision support towards designing and implementing targeted tsetse and tsetse-transmitted African trypanosomiasis control strategies amidst entomological data shortages due to limited resources and absence of expertise. [ABSTRACT FROM AUTHOR] more...
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- 2021
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32. How geographic and climatic factors affect the adaptation of Douglas-fir provenances to the temperate continental climate zone in Europe.
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Niemczyk, Marzena, Chmura, Daniel J., Socha, Jarosław, Wojda, Tomasz, Mroczek, Piotr, Gil, Wojciech, and Thomas, Barb R.
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TEMPERATE climate ,CLIMATE change ,FROST ,GEOGRAPHY - Abstract
The contribution of Douglas-fir (Df) to European forests is likely to increase as the species is a potential adaptation option to climate change. In this study, we investigated growth and survival of Df seed sources to fill a knowledge gap regarding recommendations for the future use of Df provenances in Poland. Our experimental test site represents the most continental climate among all Df trials installed in the IUFRO 1966–67 test series in Europe. At this unique single site, we evaluated the performance of 46 Df provenances from North America, and nine local landraces of unknown origin. Repeated measurements of tree diameter, height, and volume were analysed, to age 48, representing integrated responses to geographic and climatic conditions. Significant variation in survival and productivity-related traits were found, with the interior Df provenances performing best, in contrast to previous European reports. The higher survivability and volume of the interior provenances resulted from their superior frost resistance. The low precipitation seasonality at the location of seed origin provided an additional advantage to the trees at the test site. Geographic and climatic factors of seed origin explained most of the variation in productivity (77 and 64%, respectively). The tested landraces exhibited diverse performance, implying that naturalized local seed sources in Poland need improvement and perhaps enrichment with new genetic material from North America, while considering geography and climate. Assisted migration programs should consider the limitations imposed by both frost and drought events in guiding future Df selections for continental climates. Further field testing, early greenhouse screening and DNA testing are also recommended. [ABSTRACT FROM AUTHOR] more...
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- 2021
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33. Opportunities for winter prescribed burning in mixed conifer plantations of the Sierra Nevada.
- Author
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York, Robert A., Levine, Jacob, Russell, Kane, and Restaino, Joseph
- Abstract
Background: Young, planted forests are particularly vulnerable to wildfire. High severity effects in planted forests translate to the loss of previous reforestation investments and the loss of future ecosystem service gains. We conducted prescribed burns in three ~35-year-old mixed conifer plantations that had previously been masticated and thinned during February in order to demonstrate the effectiveness of winter burning, which is not common in the Sierra Nevada, California. Results: On average, 59% of fine fuels were consumed and the fires reduced shrub cover by 94%. The average percent of crown volume that was damaged was 25%, with no mortality observed in overstory trees 1 year following the fires. A plot level analysis of the factors of fire effects did not find strong predictors of fuel consumption. Shrub cover was reduced dramatically, regardless of the specific structure that existed in plots. We found a positive relationship between crown damage and the two variables of Pinus ponderosa relative basal area and shrub cover. But these were not particularly strong predictors. An analysis of the weather conditions that have occurred at this site over the past 20 years indicated that there have consistently been opportunities to conduct winter burns. On average, 12 days per winter were feasible for burning using our criteria. Windows of time are short, typically 1 or 2 days, and may occur at any time during the winter season. Conclusions: This study demonstrates that winter burning can be an important piece of broader strategies to reduce wildfire severity in the Sierra Nevada. Preparing forest structures so that they can be more feasible to burn and also preparing burn programs so that they can be nimble enough to burn opportunistically during short windows are key strategies. Both small landowners and large agencies may be able to explore winter burning opportunities to reduce wildfire severity. [ABSTRACT FROM AUTHOR] more...
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- 2021
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34. Northern spotted owl nesting forests as fire refugia: a 30-year synthesis of large wildfires.
- Author
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Lesmeister, Damon B., Davis, Raymond J., Sovern, Stan G., and Yang, Zhiqiang
- Abstract
Background: The northern spotted owl (Strix occidentalis caurina) is an Endangered Species Act-listed subspecies that requires coniferous forests with structurally complex and closed-canopy old-growth characteristics for nesting. With climate change, large wildfires are expected to become more common within the subspecies’ range and an increasing threat to these types of forests. Understanding fire severity patterns related to suitable nesting forest will be important to inform forest management that affects conservation and recovery. We examined the relationship between fire severity and suitable nesting forest in 472 large wildfires (> 200 ha) that occurred in the northern spotted owl range during 1987–2017. We mapped fire severities (unburned-low, moderate, high) within each fire using relative differenced normalized burn ratios and quantified differences in severity between pre-fire suitable nesting forest (edge and interior) and non-nesting forest. We also quantified these relationships within areas of three fire regimes (low severity, very frequent; mixed severity, frequent; high severity, infrequent). Results: Averaged over all fires, the interior nesting forest burned at lower severity than edge or non-nesting forest. These relationships were consistent within the low severity, very frequent, and mixed severity, frequent fire regime areas. All forest types burned at similar severity within the high severity, infrequent fire regime. During two of the most active wildfire years that also had the largest wildfires occurring in rare and extreme weather conditions, we found a bimodal distribution of fire severity in all forest types. In those years, a higher amount—and proportion—of all forest types burned at high severity. Over the 30-year study, we found a strong positive trend in the proportion of wildfires that burned at high severity in the non-nesting forests, but not in the suitable nesting forest types. Conclusions: Under most wildfire conditions, the microclimate of interior patches of suitable nesting forests likely mitigated fire severity and thus functioned as fire refugia (i.e., burning at lower severity than the surrounding landscape). With changing climate, the future of interior forest as fire refugia is unknown, but trends suggest older forests can dampen the effect of increased wildfire activity and be an important component of landscapes with fire resiliency. [ABSTRACT FROM AUTHOR] more...
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- 2021
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35. Disentangling the effect of topography and microtopography on near-ground growing-season frosts at the boreal-temperate forest ecotone (Québec, Canada).
- Author
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Marquis, Benjamin, Bergeron, Yves, Simard, Martin, and Tremblay, Francine
- Subjects
ECOTONES ,TOPOGRAPHY ,TEMPERATE forests ,ALTITUDES ,ATMOSPHERIC temperature ,DRAINAGE - Abstract
Permanent landscape attributes such as topography (elevation [m]) and microtopography (local variation in elevation [cm]) can increase the risk of cold air drainage down-slopes and in microtopographic depressions, causing important temperature gradients that generate localized growing-season frosts. Since most studies on growing-season frosts are restricted to the northern parts of the boreal forest or to mountainous areas, their negative consequences on tree productivity at the boreal-temperate forest ecotone is often ignored. We quantified the intensity and probability of growing-season frosts at the boreal-temperate forest ecotone in regard to topographic and microtopographic landscape attributes, which were extracted from airborne LiDAR surveys. In situ air temperature was measured for two summers (2016–2017) with 252 temperature loggers installed in two 18-years-old spruce plantations established in both temperate and boreal mixedwood forests. Growing-season frosts were more intense and probable at the boreal mixedwood forest site compared to the temperate forest site. Still, at both sites, when growing-season frost occurred, air temperature could vary by 4 °C along the elevation gradient of 15 m, often reaching sub-zero values at low elevation while reaching above-freezing values at high elevation. The importance of microtopography on the risk of sub-zero temperatures increased where frost events were less likely to occur such as at the temperate forest and at high elevation. Considering that growing-season frosts can considerably reduce tree productivity, the effects of both topography and planting microsite should be considered when determining where to establish plantations in the landscape and to determine suitable frost-free planting microsites within a plantation. [ABSTRACT FROM AUTHOR] more...
- Published
- 2021
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36. Replicate analyses of OSPAR beach litter data.
- Author
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Schulz, Marcus, Unger, Bianca, Philipp, Carolin, and Fleet, David M.
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BEACHES ,STATISTICAL power analysis ,COASTS - Abstract
Replicate surveys of beach litter have seldom been performed in the past. In this study, replicate surveys of beach litter were conducted on the beach north of Hörnum (Sylt, Germany), from 2015 to 2019, applying a slightly modified OSPAR protocol of beach litter monitoring. Descriptive statistics and power analyses were calculated on data resulting from these replicate surveys, to find out whether the scatter of replicate beach litter data decreases and the statistical power increases with increasing numbers of replicate surveys. From 2015 to 2019, mean total abundances, given as numbers of litter items, ranged from 19 to 185 litter items on a 50 m section of beach. With increasing numbers of replicate surveys, the scatter given by the coefficient of variation (CV) significantly increased up to 113%. Statistical power considerably increased with increasing numbers of replicate beach sections, e.g. from 82% (two beach sections) to nearly 100% (five beach sections) for a given reduction of beach litter of 50%. Based on these results from a morphologically straight coastline, the use of replicate surveys would be sensible for the future monitoring of beach litter. However, there is high need for studies, which consider coastlines with varying morphology. [ABSTRACT FROM AUTHOR] more...
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- 2021
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37. Effects of altered fire intervals on critical timber production and conservation values.
- Author
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Cary, Geoffrey J., Blanchard, Wade, Foster, Claire N., and Lindenmayer, David B.
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LOGGING ,FIRE management ,MOUNTAIN forests ,TEMPERATE forests ,FOREST fires ,TIMBER - Abstract
Forests exhibit thresholds in disturbance intervals that influence sustainability of production and natural values including sawlog production, species existence and habitat attributes. Fire is a key disturbance agent in temperate forests and frequency of fire is increasing, threatening sustainability of these forest values. We used mechanistically diverse, theoretical fire interval distributions for mountain ash forest in Victoria, Australia, in the recent past and future to estimate the probability of realising: (i) minimum sawlog harvesting rotation time; (ii) canopy species maturation; and (iii) adequate habitat hollows for fauna. The likelihood of realising fire intervals exceeding these key stand age thresholds diminishes markedly for the future fire regime compared with the recent past. For example, we estimate that only one in five future fire intervals will be sufficiently long (~80 years) to grow sawlogs in this forest type, and that the probability of forests developing adequate habitat hollows (~180 years) could be as low as 0.03 (3% of fire intervals). Therefore, there is a need to rethink where sawlogs can be sourced sustainably, such as from fast-growing plantations that can be harvested and then regrown rapidly, and to reserve large areas of existing 80-year-old forest from timber harvesting. The average interval between forest fires is expected to markedly shorten in mountain ash forests of Victoria, Australia, by 2070. Simple models of the likelihood of fire intervals required for trees to mature, grow sawlogs, and develop hollows for habitat are presented for the recent past and the future. [ABSTRACT FROM AUTHOR] more...
- Published
- 2021
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38. Wildland fire as an atmospheric source of viable microbial aerosols and biological ice nucleating particles.
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Moore, Rachel A., Bomar, Chelsey, Kobziar, Leda N., and Christner, Brent C.
- Abstract
The environmental sources of microbial aerosols and processes by which they are emitted into the atmosphere are not well characterized. In this study we analyzed microbial cells and biological ice nucleating particles (INPs) in smoke emitted from eight prescribed wildland fires in North Florida. When compared to air sampled prior to ignition, samples of the air–smoke mixtures contained fivefold higher concentrations of microbial cells (6.7 ± 1.3 × 10
4 cells m−3 ) and biological INPs (2.4 ± 0.91 × 103 INPs m−3 active at temperatures ≥ −15 °C), and these data significantly positively correlated with PM10 . Various bacteria could be cultured from the smoke samples, and the nearest neighbors of many of the isolates are plant epi- and endophytes, suggesting vegetation was a source. Controlled laboratory combustion experiments indicated that smoke emitted from dead vegetation contained significantly higher numbers of cells, INPs, and culturable bacteria relative to the green shrubs tested. Microbial viability of smoke aerosols based on formazan production and epifluorescent microscopy revealed no significant difference in the viable fraction (~80%) when compared to samples of ambient air. From these data, we estimate each fire aerosolized an average of 7 ± 4 × 109 cells and 2 ± 1 × 108 biological INPs per m2 burned and conclude that emissions from wildland fire are sources of viable microbial aerosols to the atmosphere. [ABSTRACT FROM AUTHOR] more...- Published
- 2021
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39. Spatial patterns of nineteenth century fire severity persist after fire exclusion and a twenty-first century wildfire in a mixed conifer forest landscape, Southern Cascades, USA.
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Taylor, Alan H., Airey-Lauvaux, Catherine, Estes, Becky, Harris, Lucas, and Skinner, Carl N.
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WILDFIRE prevention ,FIRE management ,CONIFEROUS forests ,MIXED forests ,NINETEENTH century ,LANDSCAPES ,TWENTY-first century - Abstract
Context: Spatial patterns of fire severity are influenced by fire-vegetation patch dynamics and topography. Since the late nineteenth century, fire exclusion has increased fuels and recent fire severity patterns may diverge from historical patterns. Objectives: We used data from a 2008 wildfire burning in a landscape with known nineteenth century fire severity patterns to answer the following questions: (1) Were the spatial patterns of fire severity and fire effects after the 2008 fire similar to those in the late nineteenth century? (2) What factors were most important in controlling spatial patterns of fire severity in 2008? Methods: Fire severity patterns in the late nineteenth century were identified by Beaty and Taylor (J Veg Sci 18:879, 2001) using dendroecology. Plots were remeasured after the 2008 fire and geospatial layers of vegetation type, topography, fire weather, daily fire extent and fire severity were used to identify controls on 2008 fire severity. Results: Fire severity in 2008 varied in ways similar to the nineteenth century. Tree mortality and bark char in plots were lowest on lower slopes and southwest facing slopes, intermediate on middle slopes, and highest on upper slopes and northeast slopes. At the landscape scale, vegetation type, elevation, slope aspect, slope position and weather were the variables controlling fire severity. Conclusions: Spatial patterns of fire severity persisted, despite more than a century of fire exclusion. Our findings suggest that wildfires burning under moderate conditions even with a warming climate can help reduce the fire deficit and promote forest resilience in fire prone landscapes. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
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40. Heterogeneity in flow disturbance around river confluences influences spatial patterns in native and non-native species co-occurrence.
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Boddy, Nixie C., Booker, Doug J., and McIntosh, Angus R.
- Abstract
Given the prevalence of invasive species and high rates of habitat homogenisation across the globe, understanding how these drivers interact to influence native species assemblages is crucial. In river networks, confluences create discontinuities in physical conditions, likely creating hotspots of heterogeneity that influence interactions between native and invasive fish. We examined how spatial configuration of confluences affected the outcome of interactions between native galaxiids and non-native salmonids in New Zealand alpine rivers. Electrofishing in mainstem and tributary branches of twelve replicate confluences revealed highly context-dependent distributions, contingent upon interactions between: (a) the combination of flood disturbance history in confluence branches; (b) distance to the confluence; and (c) the direction of flow, either upstream or downstream, of the confluence. Shifts in native–invasive species relative abundance were determined by the preference of large predatory salmonids for more hydrologically stable conditions, which subsequently limited the abundance of young-of-year galaxiids, and meant galaxiids were more abundant in flood-prone conditions. Distance-from-confluence effects were stronger upstream than downstream, suggesting that flow direction had an important influence on dispersal. Tributary flow regimes also predictably influenced downstream physical conditions, thereby affecting predatory salmonid distribution which likely controlled galaxiid distributions. Overall, our results reveal strong spatial context-dependency in fish assemblages in river networks, and demonstrate how flow regime influences are spatially transferred at confluences, thereby creating areas of influential riverscape heterogeneity. Understanding the influence of such heterogeneity enables ecologically significant locations to be identified, particularly for management of native species vulnerable to invaders. [ABSTRACT FROM AUTHOR] more...
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- 2020
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41. Salvage logging effects on regulating ecosystem services and fuel loads.
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Leverkus, Alexandro B, Gustafsson, Lena, Lindenmayer, David B, Castro, Jorge, Rey Benayas, José María, Ranius, Thomas, and Thorn, Simon
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SALVAGE logging ,FOREST management ,FUEL ,ECOLOGICAL impact ,DECISION making ,FOREST fire ecology ,ECOSYSTEM services - Abstract
Salvage logging, or logging after natural disturbances such as wildfires, insect outbreaks, and windstorms, is carried out to recover some of a forest's natural and/or economic capital. However, trade‐offs between management objectives and a lack of consensus on the ecological consequences of salvage logging impair science‐based decision making on the management of forests after natural disturbances. We conducted a global meta‐analysis of the impacts of salvage logging on regulating ecosystem services and on fuel loads, as a frequent post‐disturbance objective is preventing subsequent wildfires that could be fueled by the accumulation of dead trunks and branches. Salvage logging affected ecosystem services in a moderately negative way, regardless of disturbance type and severity, time elapsed since salvage logging, intensity of salvage logging, and the group of regulating ecosystem services being considered. However, prolonging the time between natural disturbance and salvage logging mitigated negative effects on regulating ecosystem services. Salvage logging had no overall effect on surface fuels; rather, different fuel types responded differently depending on the time elapsed since salvage logging. Delaying salvage logging by ~2–4 years may reduce negative ecological impacts without affecting surface fuel loads. [ABSTRACT FROM AUTHOR] more...
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- 2020
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42. A new Caribbean species of Hylaeanura Arlé, 1966 (Collembola, Neanuridae, Pseudachorutinae).
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Ospina-Sánchez, Claudia M., Palacios-Vargas, José G., and González, Grizelle
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COLLEMBOLA ,SETAE ,SPECIES ,ACARIFORMES - Abstract
We here describe a new Collembola species, Hylaeanura emiliae sp. nov., from the Luquillo Experimental Forest in Puerto Rico. We describe H. emiliae sp. nov. as a distinct species based on the enlarged sensilla s3 in antennal segment IV, the absence of modified sensorial setae in abdominal segment IV and the presence of four setae on each dens. An updated key with illustrations for the identification of worldwide species of the genus is included. [ABSTRACT FROM AUTHOR] more...
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- 2020
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43. Red turpentine beetle primary attraction to (–)-β-pinene+ethanol in US Pacific Northwest ponderosa pine forests.
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Kelsey, Rick G. and Westlind, Douglas J.
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PINENE ,PONDEROSA pine ,TURPENTINE ,LOW density polyethylene ,BEETLES ,BARK beetles - Abstract
Red turpentine beetle, Dendroctonus valens (Coleoptera: Curculionidae: Scolytinae) is a non-aggressive pine bark beetle native to North America, and more aggressive invader in China. Dispersing pioneer beetles are attracted to potential host trees by oleoresin monoterpene kairomones, but respond more strongly to those combined with ethanol, a mixture often released from stressed, dying, or recently dead trees. (+)-3-Carene, usually the dominant or co-dominant monoterpene in ponderosa pine, Pinus ponderosa, is a stronger attractant than α-pinene or β-pinene where tested over a large portion of the D. valens range, while (+)-3-carene+ethanol was shown previously to attract twice the beetles of (+)-3-carene. A field test comparing D. valens attraction among the three monoterpenes when all are released with ethanol has never been reported, and was our objective. In three US Pacific Northwestern pine forests, (–)-β-pinene+ethanol lures attracted 1.4 to 1.9 times more beetles than (+)-3-carene+ethanol. (+)- or (±)-α-pinene+ethanol lures were least attractive. A 1:1:1 monoterpene mixture+ethanol lure attracted more beetles than the 1:1:1 lure, but it was not statistically higher. Monoterpenes were dispensed from low density polyethylene bottles and their release rates monitored in laboratory and field tests. Under laboratory conditions (+)-3-carene was released much more rapidly than (+)-α-pinene or (–)-β-pinene when dispensed separately, or in a 1:1:1 mixture. (+)-3-Carene in the 1:1:1 mixture increased the release of both pinenes over their rates when dispensed separately. (–)-β-Pinene+ethanol is currently the strongest kairomone lure for D. valens attraction in US northwest pine forests, and has value for beetle detection, monitoring, research, and management. [ABSTRACT FROM AUTHOR] more...
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- 2020
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44. The Fire and Tree Mortality Database, for empirical modeling of individual tree mortality after fire.
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Cansler, C. Alina, Hood, Sharon M., Varner, J. Morgan, van Mantgem, Phillip J., Agne, Michelle C., Andrus, Robert A., Ayres, Matthew P., Ayres, Bruce D., Bakker, Jonathan D., Battaglia, Michael A., Bentz, Barbara J., Breece, Carolyn R., Brown, James K., Cluck, Daniel R., Coleman, Tom W., Corace III, R. Gregory, Covington, W. Wallace, Cram, Douglas S., Cronan, James B., and Crouse, Joseph E. more...
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TREE mortality ,WILDFIRES ,DATABASES ,TREE injuries ,PLANT morphology - Abstract
Wildland fires have a multitude of ecological effects in forests, woodlands, and savannas across the globe. A major focus of past research has been on tree mortality from fire, as trees provide a vast range of biological services. We assembled a database of individual-tree records from prescribed fires and wildfires in the United States. The Fire and Tree Mortality (FTM) database includes records from 164,293 individual trees with records of fire injury (crown scorch, bole char, etc.), tree diameter, and either mortality or top-kill up to ten years post-fire. Data span 142 species and 62 genera, from 409 fires occurring from 1981-2016. Additional variables such as insect attack are included when available. The FTM database can be used to evaluate individual fire-caused mortality models for pre-fire planning and post-fire decision support, to develop improved models, and to explore general patterns of individual fire-induced tree death. The database can also be used to identify knowledge gaps that could be addressed in future research. Measurement(s) plant morphology trait • tree mortality • fire • tree fire injury • wildfire Technology Type(s) digital curation Factor Type(s) year of data collection • geographic location of fire • tree fire injury Sample Characteristic - Organism trees Sample Characteristic - Environment forest ecosystem Sample Characteristic - Location Cascades Region • Blue Mountains • Far Northern Rockies • Sierra Nevada • Piedmont Province • Region of Piedmont • Atlantic and Gulf Coastal Plain Floristic Province • Northern Rocky Mountains Provincial Park Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.12369293 [ABSTRACT FROM AUTHOR] more...
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- 2020
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45. Observations on habitat preference of juvenile eastern hellbender salamanders (Cryptobranchus alleganiensis).
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Unger, Shem, Bodinof-Jachowski, Catherine, Diaz, Lauren, and Williams, Lori A.
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HABITAT selection ,SALAMANDERS ,ANIMAL behavior ,AMPHIBIANS ,AQUARIUMS ,GRAVEL ,AQUATIC habitats - Abstract
Laboratory experiments have provided a wealth of knowledge on antipredator responses and habitat preference in both terrestrial and aquatic salamanders, many of which are difficult to study under natural conditions. However, there remains a dearth of carefully designed experiments to elucidate habitat preferences of aquatic salamanders, many of which are of growing conservation concern. This experimental study evaluated shelter selection of nearly threatened larval eastern hellbender salamanders, Cryptobranchus alleganiensis, in North Carolina. We performed three experiments: 1) ability to burrow under 50% embedded cobble, 2) preference for cobble (~ 120–150 mm) versus gravel (~ 30–60 mm) in an aquarium (ex situ), and 3) preference for cobble over gravel in a natural stream setting (in situ). We found that salamanders (N = 11) showed a preference for cobble (~ 135–137 mm) in both aquarium and in-stream testing environments (87.7% and 88.5% of time, respectively) over gravel and burrowed under cobble in 95% of aquarium and in-stream trials. Moreover, salamanders were unable to burrow under 50% embedded cobble and were actively moving 38.1% of the time in our burrowing experiment, highlighting the potential for larvae to remain exposed to predators if streams contain buried substrate. Our study provides preliminary evidence on the behavior of these cryptic larval salamanders, suggesting that they prefer cobble substrate and are unable to utilize embedded cobble. These findings have management implications for juveniles of this species, particularly in areas where prolonged sedimentation has the potential to make cobble unavailable for larvae. [ABSTRACT FROM AUTHOR] more...
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- 2020
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46. Assessing and modeling total height and diameter increment of ponderosa pine planted in Minnesota, USA.
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Russell, Matthew B., Windmuller-Campione, Marcella A., Anderson, Brian D., and David, Andrew J.
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PONDEROSA pine ,RED pine ,INTRODUCED species ,INTRODUCED plants ,TREE height ,TREE growth - Abstract
Forest managers are increasingly planting non-native tree species that are adapted to anticipated future conditions such as increased droughts. This work quantified individual tree growth patterns of ponderosa pine (Pinus ponderosa P. & C. Lawson), a western US species, planted outside of its natural range in Minnesota, USA. After 50 years, survival was as high as 69% for some ponderosa pine seed sources, and individuals from the Black Hills, Eastern High Plains, and South and East Montana regions of the western US were some of the tallest and largest diameter trees grown in Minnesota. Predictions of total tree height and diameter increment displayed the lowest bias when equations for ponderosa pine in the western US were used rather than equations for red pine (Pinus resinosa Ait.) in Minnesota, a species that occupies a similar ecological niche. These results indicate that using existing growth and yield equations from a species' native range may provide a suitable representation of growth and yield patterns if observations from outside the species' native range are lacking. Historical data from provenance trials such as these can provide a long-term record to quantify the growth potential of non-native species in anticipation of future climate scenarios. [ABSTRACT FROM AUTHOR] more...
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- 2020
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47. Burn weather and three-dimensional fuel structure determine post-fire tree mortality.
- Author
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Jeronimo, Sean M. A., Lutz, James A., R. Kane, Van, Larson, Andrew J., and Franklin, Jerry F.
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TREE mortality ,POST-fire forests ,FUEL ,ECOLOGICAL resilience ,WEATHER ,BIOLOGICAL dressings - Abstract
Context: Post-fire tree mortality is a spatially structured process driven by interacting factors across multiple scales. However, empirical models of fire-caused tree mortality are generally not spatially explicit, do not differentiate among scales, and do not differentiate immediate from delayed mortality. Objectives: We aimed to quantify cross-scale linkages between forest structure—including spatial patterns of trees—and the progression of mortality 1–4 years post-fire in terms of rates, causes, and underlying demography. Methods: We used data from a long-term study site in the Sierra Nevada, California to build a post-fire tree mortality model predicted by lidar-measured estimates of structure. We calculated structural metrics at scales from individual trees to 90 × 90 m neighborhoods and combined them with metrics for topography, site water balance, and burn weather to predict immediate and delayed post-fire tree mortality. Results: Mortality rates decreased while average diameter of newly killed trees increased each year post-fire. Burn weather predictors as well as interactive terms across scales improved model fit and parsimony. Including landscape-scale information improved finer-scale predictions but not vice versa. The amount of fuel, fuel configuration, and burning conditions predicted total mortality at broader scales while tree group-scale fuel connectivity, tree species fire tolerance, and local stresses predicted the fine-scale distribution, timing, and agents of mortality. Conclusions: Landscape-scale conditions provide the template upon which finer-scale variation in post-fire tree mortality is arranged. Post-fire forest structure is associated with the etiologies of different mortality agents, and so landscape-level heterogeneity is a key part of ecosystem stability and resilience. [ABSTRACT FROM AUTHOR] more...
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- 2020
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48. New species of Furculanurida (Collembola, Neanuridae, Pseudachorutinae) from the Luquillo Mountains, Puerto Rico.
- Author
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Ospina-Sánchez, Claudia M., Palacios-Vargas, José G., and González, Grizelle
- Subjects
COLLEMBOLA ,SPECIES ,MOUNTAINS ,ACARIFORMES ,SETAE ,EYE - Abstract
A new species of Furculanurida is described and illustrated. Furculanurida bistribus sp. nov. differs from other species of the genus by the presence of three eyes, three setae on the dens, and the white and purple coloration pattern. A key for identification of the world species of the genus is included. [ABSTRACT FROM AUTHOR] more...
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- 2020
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49. A spatially explicit empirical model of structural development processes in natural forests based on climate and topography.
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Yamaura, Yuichi, Lindenmayer, David, Yamada, Yusuke, Gong, Hao, Matsuura, Toshiya, Mitsuda, Yasushi, and Masaki, Takashi
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FOREST microclimatology ,LOGGING ,OLD growth forests ,FOREST surveys ,TOPOGRAPHY ,MID-ocean ridges - Abstract
Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
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- 2020
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50. Urban arborization management plan: tool design for efficiency and public safety.
- Author
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Carvalho, Joema and Maranho, Leila Teresinha
- Subjects
PUBLIC safety ,CITY dwellers ,URBAN planning ,ANADENANTHERA ,PARKING lots - Abstract
The inventory of the urban arborization of Positivo University parking lots in Ecoville Campus was conducted through census criteria, concerning the surroundings conflicts related to tree health, origin and phenology, that were scored and weighted. There were 393 individuals, 12 species and five families where 60% were native to Brazil. The main canopy criteria was the reaching branches on the access road in a proportion of 40%; in the trunk analysis, it was observed lesion (45%) and rot (40%); at the base's analysis it was verified injury (43%) and root damage (35%) and exposed root (25%). The presence of fruit (26%) was higher than the flowering. Handroanthus albus presented the best result for the criteria, unlike Anadenanthera macrocarpa and Tipuana tipu. The trees showed a landscaping potential, however, the space available for the large size ones was not adequate and the large size species intensified the conflicts, when there was no planning. The species characteristics should be observed, in relation to the three-dimensional space availability. Thus, future conflicts that can be avoided endanger tree health, urban infrastructure and residents which can lead to economic losses. For this reason, the elaboration of the Municipal Urban Arborization Plan is considered primordial. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
- Full Text
- View/download PDF
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