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Effective forest management and conservation are increasingly critical in addressing the challenges posed by climate change. Advances in remote sensing technologies, such as terrestrial laser scanning, offer promising tools for more accurate assessments in forestry research. This study explores the application of TLS in biomass estimation by conducting a bibliometric analysis of scientific articles indexed in Scopus and the Web of Science. By examining the literature from 2010 to 2024, the study identifies key trends, knowledge gaps, and emerging research opportunities, as well as practical applications in forest management and conservation. The analysis reveals a significant rise in scientific output on TLS, with an average annual growth rate of 8.16%. The most cited works address biomass estimation at the individual tree level using laser scanning data. China and the United States lead in the publication volume with 11 articles. The collaboration network highlights research disparities among regions such as Latin America. Overall, TLS has proven effective for the non-destructive measurement of forest variables and biomass.

The article thoroughly investigates the relationships between terrain features and tree measurements derived from aerial laser scanning (ALS) data and field surveys in a 1067-hectare forested area. A digital elevation model (DEM) was generated from ALS data, which was then used to derive additional layers such as slope, aspect, topographic position index (TPI), and landforms. The authors developed a mathematical procedure to determine the radii for the topographic position index. The canopy height model was created, and individual trees were segmented using a novel voxel aggregation method, allowing for the calculation of tree height and crown size. Accuracy assessments were conducted between ALS-derived data and field-collected data. Terrain variability within each forest unit was evaluated using characteristics such as standard deviation, entropy, and frequency. The relationships between tree height and the derived topographic features within forest subcompartments, as well as the correlation between the height yield map for the entire area and the TPI layer, were analysed. The authors found strong correlation between the topographic position index and tree heights in both cases. The presented remote-sensing-based methodology and the results can be effectively used in digital forest site mapping, complemented by field sampling and laboratory soil analyses, and, as final goal, in carbon stock assessment. [ABSTRACT FROM AUTHOR]

Effective forest management and conservation are increasingly critical in addressing the challenges posed by climate change. Advances in remote sensing technologies, such as terrestrial laser scanning, offer promising tools for more accurate assessments in forestry research. This study explores the application of TLS in biomass estimation by conducting a bibliometric analysis of scientific articles indexed in Scopus and the Web of Science. By examining the literature from 2010 to 2024, the study identifies key trends, knowledge gaps, and emerging research opportunities, as well as practical applications in forest management and conservation. The analysis reveals a significant rise in scientific output on TLS, with an average annual growth rate of 8.16%. The most cited works address biomass estimation at the individual tree level using laser scanning data. China and the United States lead in the publication volume with 11 articles. The collaboration network highlights research disparities among regions such as Latin America. Overall, TLS has proven effective for the non-destructive measurement of forest variables and biomass. [ABSTRACT FROM AUTHOR]

The continuous and reliable assessment of crop water status through water indicators enables the sustainable management of water resources, especially in arid or semi-arid climate scenarios exacerbated by climate change. Therefore, the main objective of this study is to determine and compare the sensitivity of indices derived from trunk diameter fluctuations for the accurate and automatic detection of changes in the water status of cherry trees. The water stress indicators examined are maximum daily trunk shrinkage (MDS), trunk growth rate (TGR), early daily trunk shrinkage (EDS), and late daily trunk shrinkage (LDS). During two growing seasons, 'Lapins' sweet cherry trees were subjected to different water stress levels: (i) a control treatment irrigated at 115% of crop evapotranspiration demand to ensure non-limiting water conditions, and (ii) a deficit irrigation treatment, with two irrigation withholding cycles. Vegetative growth was affected by water stress. Trunk daily growth rate and late daily trunk shrinkage exhibited a high variability and did not clearly show differences in plant water status. Both EDS and MDS showed a third-degree polynomial relationship with Ψstem. MDS had a lineal relationship with Ψstem of up to −1.4 MPa; however, further decreases in Ψstem did not necessarily lead to increased MDS. In contrast, EDS became non-linear at −1.8 MPa, making it a more useful plant water indicator than MDS for 'Lapins' sweet cherry trees when detecting severe water stress conditions. The frequencies of both MDS and EDS decreased from 85% to 35% when water stress increased. Therefore, the information provided by MDS and EDS frequencies, along with their daily values, could be useful as irrigation management tools for sweet cherry trees. [ABSTRACT FROM AUTHOR]

Azadirachta indica (indian neem) is an exotic species that presents high adaptability to different edaphoclimatic conditions, being employed for several uses, mainly wood for energy purposes. use of its wood for energy purposes. In this context, the aim of this research was to evaluate the physicochemical and energetic characteristics of charcoal from wood in two diametric classes: class 1 (8,59 – 10,50 cm) and class 2 (4,78 – 6,07 cm). 10 trees from the indian neem species were randomly sampled (Azadirachta indica), five individuals for each diametric class, with different ages and taken cutting disk to 0 (basis) 25, 50, 75 and 100% from the commercial level, of which the volume of wood with bark, without bark, the percentage volume of bark and dry mass of wood were calculated. Diametrically opposed wedges were used to determine the basic density of the wooden disks. The remaining wedges of the disks were applied for carbonization, evaluation of yields and physical and energetic characteristics of the produced charcoal. The test of Test t of Students (p ≤ 0,05) was employee in the analysis and assessment of the results. Diametric class 1 showed a higher mean basic density (0,57 g cm-3 ) than the mean value of class 2 (0,47 g cm-3 ). Diametric class 2 had the highest levels of bark (20,94%). The charcoal yield was higher in class 1 (35.36%). The Azadirachta indica Showed good potential for the production of charcoal, which could reduce the anthropic pressure on the native species intended for this purpose. [ABSTRACT FROM AUTHOR]

The primary climatic characteristic of olive cultivation in Peru is the coastal desert environment with moderate temperatures, minimal precipitation, and high atmospheric water content during the winter season. This report presents a comprehensive study on water and carbon fluxes in a drip-irrigated olive orchard in Pisco Province, Peru, addressing the current lack of information on olive physiology and water management under these environmental conditions. The eddy covariance system installed in September 2019 showed an average ET of 2.18 ± 0.38 mm d−1, with seasonal variation. Drip irrigation was set at 60 m3 ha−1 d−1 during the growing season and reduced to half that amount in the winter. The study suggests that using deficit irrigation based on affordable dendrometry sensors could reduce water use by close to 30% while potentially preserving biomass gain and fruit yields. This could help improve water management in olive cultivation in coastal Peru.

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco 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.)

Tropical forests are being cleared at an accelerating rate, despite being one of the most important habitats for global biodiversity. Many remaining tropical forest tracts are now highly degraded and fragmented, which presents a major problem for sensitive and threatened forest-dwelling species that depend on this habitat for survival. In this study, we assessed the impacts of forest fragmentation, and its associated edge-effects, on tree species diversity, tree size, and structural diversity within the transitional forests of north west Madagascar. Using data collected from 9,619 trees within 200 vegetation plots, we calculated species diversity indices, a range of dendrometry measurements, and Shannon-Weaver diversity indices of structure, which we compared among core and edge areas of a continuous forest and a fragmented forest. We found that species diversity, tree size, and structural diversity was significantly reduced in fragmented forest, and within forest edge areas in comparison to core, continuous forest. We also observed species diversity and structural diversity to be strongly influenced by the total size, core area size, and shape of forest fragments. Whilst we found fragmentation and edge-effects to individually impact tree species diversity, size and structural diversity, fragmentation and edge-effects are strongly correlated and affect natural forest synergistically. Our results provide evidence that forest fragmentation seriously degrades habitat quality and integrity of transitional forests, which is of great concern for the threatened species that inhabit them. Urgent conservation efforts are needed to halt ongoing forest fragmentation throughout the tropics, and reforestation and restoration efforts are required to reconnect isolated forest patches and to reduce forest edge area. [ABSTRACT FROM AUTHOR]

Studies that seek to identify potential techniques for obtaining diameter values at 1.30 m from the ground from tree height data are necessary, especially when considering the use of airborne Lidar in forest inventory activity. In this sense, this work aimed to evaluate two artificial intelligence tools for this purpose, namely the neurofuzzy inference systems and the artificial neural networks. Four models were tested to obtain estimates for the diameter variable, which were prepared by combining the independent variables useful area per plant, age and height. After processing, the statistics of bias, square root of the mean squared error in percentage, correlation and mean percentage error were calculated, in addition to the preparation of scatter plots and histogram of residues. It was observed that, for the estimation of the diameter in both techniques, the use of the model with all independent variables obtained the best values for the analysis statistics. It can be concluded that both tools can be used to estimate the diameter, with the neuro-fuzzy inference system being more suitable for its processing speed and small variability between the values obtained in different training sessions for the same database. [ABSTRACT FROM AUTHOR]

There is a great need to identify interactions among silvopastoral systems and microclimatic indicators that describe the effect of trees compared to conventional pasture systems without trees. The objective of this study was to evaluate thermal conditions in a silvopastoral system and a pasture area exposed to full sunlight in the eastern Amazon, Brazil. The silvopastoral system was composed of the forest tree species Bertholletia excelsa H.B.K., Dipteryx odorata (Aubl.) Willd, and Khaya grandifoliola C.DC.. During the monitoring period, a forest inventory was carried out that included 30 trees from each species for which thermal profiles were created using a high-precision thermographic camera. Near-infrared thermography showed a positive and direct correlation with dendrometric variables. Silvopastoral systems with K. grandifoliola reduced the heat profile the most compared to conditions in a pasture fully exposed to sunlight, which demonstrates the ecosystem service provided by trees for thermal regulation in these systems. The microclimatic conditions explain the greater presence of bovines in the silvopastoral system as they were most likely in search of the thermal comfort provided by the trees during the period of the highest daytime temperatures. The silvopastoral system benefits the caloric balance and thermal comfort of pasture animals. [ABSTRACT FROM AUTHOR]

This paper explores the use of Terrestrial Laser Scanning (TLS) data to estimate tree dendrometric characteristics, namely diameter at breast height (DBH), height and total volume in a monitoring network for spruce. The study area is located in Romania, in the western part of the Southern Carpathians, in the Țarcu Mountains. Reference data (tree positions, DBH, heights) were taken with high precision by field measurements. Tree segmentation from TLS data acquired in survey areas with a large number of trees and the presence of shrubs brings modeling problems, resulting a low estimation accuracy, therefore Hough transform was applied in DBH estimation to fit circles to existing cross sections. Thus, even when only a fragment of the trunk is available, DBH can be estimated from the curvature of the section. The processing and analysis of the TLS data sets obtained through field inventories and those based on TLS data was carried out using the FORTLS, lidR, rTLS, TreeLS, packages of the R software. Parameters used in the segmentation algorithm set the condition that in a radius of 40 cm around the identified trunk does not exist another segmented trunk. The results obtained show that there is a strong significant correlation (r= 0.988**) between the plot average of DBH values measured in the field and the plot average of the estimated ones, with a root mean square error (RMSE) value of 1.52 cm, for the same trees, based on point clouds. Moreover, between the plot average of tree heights measured in the field and the plot average of the heights estimated for the same trees there was obtained a strong significant correlation (r=0.901**) and an RMSE value of 1.42 m. The results of this study indicate that using this methodology it was possible to estimate 92.3% of the total volume measured in the field. [ABSTRACT FROM AUTHOR]

This study aims to assess the current state of health of the cork oak (Quercus suber) and its evolution in the forest of Zouagha (Mila). For this, eight plots were chosen at random. The dendrometric parameters measured are the diameter at 1.3 m above the ground and the total height of the trees, thus morphological observations were made on the aerial part of the same samples and analyzed by the tree architecture method (ARCHI). The average density of cork oak in this forest is 157±24 individual/ha with an average basal area of 27.09 ± 8.53 m²/ha. The diagnostic results show that the majority of trees in these plots are currently in classes of the ARCHI R type with a rate of 51.1%; comes in second position the ARCHI Healthy type with a percentage of 39.2; and the ARCHI S type records a low rate (7.3%). The ARCHI D and ARCHI I types are almost absent. The sanitary condition of these plots is quite good, despite the negligible presence of standing dead trees. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciencia y Tecnología Agropecuaria is the property of Agrosavia 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.)

Copyright of Revista de Ciencias Agricolas is the property of University of Narino, Faculty of Agricultural Sciences 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.)

Various edaphoclimatic factors influence mango productivity (dendrometry, flowering and fruiting). The objective of the study was to analyze the edaphoclimatic factors that influence the productivity of 3 mango varieties (Keitt, Ataúlfo and Manila) in the Papaloapan Basin in Veracruz, Mexico. Dendrometric measurements were carried out on trees of 3 mango varieties in 15 orchards (n = 5 orchards per variety) and the values of 33 edaphoclimatic variables were acquired using geographic information systems; a comparison analysis was carried out with the dendrometric and edaphoclimatic variables. The Manila variety stood out in dendrometric terms as a response to ideal edaphoclimatic conditions for its physiological development. However, the 3 varieties are developed under unique edaphoclimatic values to which they are already adapted, with Keitt and Manila having the highest productivity. [ABSTRACT FROM AUTHOR]

The complexity in the management of field tools for recording dasometric information has led to the use of allometric equations that save time, work, and costs allowing the estimation of variables that are difficult to record, such as total height (TH). The objective of this research was to develop an allometric equation for the species Alnus acuminata in order to calculate TH from the diameter at breast height (DBH). At the Obonuco-AGROSAVIA Research Center in Pasto (Nariño), dasometric information was recorded for 75 months for 200 even-aged trees. Four models were evaluated: linear, polynomial, Mixed linear (random effect per tree age), and Mixed linear (random effect per tree). For the selection of the best model, the criteria were used with the lowest values ​​of Akaike (AIC) and Bayesian (BIC). The information was analyzed using the "Nonlinear Mixed-Effects Models" package, R software. The results revealed that A. acuminata had an 81% survival; the TH average was 7.4 ± 1.3 m; and the average DBH was 9.51 ± 2.23cm. The average annual increase of DBH was 1.5 cm year-1, and the TH was 1.18 m∙ per year-1. The mixed linear model confirmed the assumptions of normality, independence, and homogeneity of variances in addition of having good criteria in its predictive performance and efficiency through the equation TH=2.07+0.35*DBH+0.95*Age. This research contributes to the management of native species of the high tropics by designing an equation for the first vegetative growth phases of A. acuminata in high mountain agroecological zones.

We present a data set resulting from the first round of a national monitoring program of forest reserves. It contains 9538 permanent plots, distributed across 111 study sites in mainland France (including Corsica). Notably focusing on dead wood measurement, this protocol has primarily been applied in strict forest reserves and special nature reserves (sensu Bollmann & Braunisch 2013), with 68% (6494) of the plots being currently located in strict forest reserves (unmanaged) and 24.7% (2363 plots) in forests unmanaged for at least 50 years. Sites cover a large variety of ecological conditions, from lowland to subalpine forests, but with an underrepresentation of Mediterranean forests (Table 1). The protocol assesses all the stages of a tree's life cycle, from seedling to decomposed lying dead wood. On each plot, a combination of three sampling techniques was used: (1) fixed‐area inventory for regeneration, standing dead trees, living trees, and coarse woody debris (CWD) with diameter over 30 cm; (2) transect lines for CWD with diameter <30 cm; and (3) fixed‐angle plot method for living trees with diameter at breast height (DBH) >30 cm (using a relascopic angle of 3%). Measurements include exact tree location (azimuth, distance), species, diameter(s), tree‐related microhabitats, decay stage and bark cover, and seedling cover. With ongoing climate change, the program network can also provide important information to monitor changes in forest ecosystems. It can also be used as forest management monitoring or conservation status assessment. These data are freely available for noncommercial scientific use (Creative Commons Attribution 4.0 CC BY SA 4.0) with attribution, and this paper must be cited if this material is reused. [ABSTRACT FROM AUTHOR]

The present study aims to show the effects of dendrometric and orographic factors on the natural regeneration of Aleppo pine (Pinus halepensis Mill.) in the Saharan Atlas, particularly the Senalba Chergui massif (Eastern Senalba mountain range) in Algeria, for its important forest area occupied by Aleppo pine in semi-aridregions. The sampling adopted is stratified and subjective; stratified sampling makes it possible to obtain representative stations for the various existing ecological situations, we divided our study area into 04 homogeneous stations according to the appearance of vegetation, the slope exposure and the type of the soil; and for every station, temporary observation plots are installed through subjective sampling, this method is used to study heterogeneous ecological environments; we installed in our study stations seventy (70) temporary plots, and the plot is a circular sampling unit that covers an area of 400 m2 . In each plot, dendrometric variables were measured: diameter at breast height, total tree height, dominant height, average density per hectare, basal area per hectare, the age of stands, and cumulative surface of crown cover; and a phytoecological survey was carried out to determine the environmental parameters, such as altitude, slope, exposure and lithology. We used the principal component analysis (PCA) to identify the homogeneous sample plots (compared to the regeneration), descriptive statistics, and the Analysis of variance (ANOVA). The number of seedlings per square meter varies between 0 and 0.23, and there are several factors affecting these results,mainly: Crown cover, density, basal area, age of stands and slope exposure. [ABSTRACT FROM AUTHOR]

Simple Summary: Black-tufted marmosets (Callithrix penicillata) regularly exploit exudates by gouging the bark from trees with their specialized teeth. Determining preferred tree species to exploit exudates is important for forest management aimed at maintaining urban populations of marmosets. We investigated the trees used by black-tufted marmosets to obtain exudates in urban forest fragments in the Brazilian Cerrado, with a view to better understanding the relationship between marmosets and obtaining exudates. We characterized the tree species, the dendrometry, and the characteristics of the holes made by the marmosets. Based on these data, we proposed a gouging effort index (ChiSI). We found 108 individuals that were exploited by black-tufted marmosets belonged to 16 species of 10 tree families. Eleven new tree species used by black-tufted marmosets for exudates were identified. Exudate exploration was predominantly of medium intensity, with round holes concentrated in the canopy. The species Tapirira guianensis and Croton urucarana were preferred. Therefore, T. guianensis and C. urucarana should be considered the most important tree species for black-tufted marmosets that live in urban forests in the Cerrado. Knowledge of the pattern of exploitation of trees can help us understand the relationship between marmosets and plants, especially in declining forests, such as those in the Brazilian Cerrado. Black-tufted marmosets (Callithrix penicillata) regularly exploit exudates by gouging the bark of trees with their specialized teeth. Determining preferred tree species to exploit exudates is important for forest management aimed at maintaining an essential food source for urban marmosets. We characterized the tree species, dendrometry, and the characteristics of the holes made by marmosets to obtain exudates. Based on these data, we proposed a gouging effort index (Chiseling Suitability Index for Marmosets, ChiSI). We identified 16 species belonging to 10 families of trees with gouging marks made by marmosets. Eleven new tree species used by black-tufted marmosets for exudates were identified in urban forests in the Cerrado. Exudate exploration was predominantly of medium intensity, with round holes concentrated in the canopy. The species Tapirira guianensis and Croton urucarana were preferred. The ChiSI was characterized by a narrow range for both T. guianensis and C. urucarana. Despite the flexibility of obtaining exudates, the black-tufted marmosets concentrate their exploitation to only a few tree species. The T. guianensis and C. urucarana tree species should be considered the most important species for management plans and the preservation of black-tufted marmosets that live in urban forests in the Cerrado. [ABSTRACT FROM AUTHOR]

Silvopastoral systems (SPS) combine tree, herbaceous, and animal components, and may contribute to improve productivity and diversification of activities over time. This study evaluated the survival rate and dendrometry of seedlings of Eucalyptus spp. (eucalyptus) and Mimosa caesalpiniifolia Benth. (sabiá) and their impact on herbage responses of Urochloa decumbens Stapf R. D. Webster (signalgrass). The randomized complete blocks design in three replications (paddocks) was used. Treatments were: 1—monoculture of signalgrass; 2—signalgrass + eucalyptus (SPS—eucalyptus); 3—signalgrass + sabiá (SPS—sabiá); 4—monoculture of eucalyptus and, 5—monoculture of sabiá. The experiment was performed during 20 months in Pernambuco, Brazil. It was observed effect (P = 0.0159) of treatments on the survival rates of the tree species, with the highest values obtained by the sabiá species (89.0 and 90.6% for SPS and monoculture respectively). There was effect of the interaction treatment × evaluation cycle (P = 0.0004) on tree height, with the monoculture of sabiá reaching a height of 284 cm. Herbage accumulation and plant-part composition of signalgrass were similar in SPS and grass monoculture (P > 0.05), however, it changed over sampling times (evaluation cycles), with the highest mean canopy height, total herbage mass and green herbage mass being observed at the beginning of the experimental period, and the lowest in the last evaluation cycle (71 and 21 cm; 10,342 and 218 kg DM ha−1; 2,985 and 152 kg DM ha−1, respectively). The highest proportions of green fractions (leaf blade and stem) occurred in September and October 2019, coinciding with the end of the rainy season. Sabiá showed a faster initial growth when cultivated in monoculture and SPS when compared to eucalyptus, but both trees initial growth did not impact the herbage accumulation and plant-part composition of signalgrass. [ABSTRACT FROM AUTHOR]

This work focused on the evaluation of four essential aspects of biomass based on peach trees grown in the Andean region of Ecuador. In one case, mathematical models have been developed allowing the amount of lignocellulosic material to be quantified from easily measurable parameters such as crown diameter, stem diameter and plant height. Performing quick surveys, these equations led to obtain the amount of biomass contained in a plot. In a second case, elemental analysis of biomass was performed in order to determine the amount of CO2 captured from the atmosphere through photosynthesis during its growth, and thus to assess the contribution of these plots in mitigating climate change. Afterwards, residual biomass from pruning was quantified and a proximal analysis was carried out. This allowed us to assess the suitability of these materials as solid biofuels. The models obtained to determine the volume of the branches gave determination coefficients of 0.98. Models to quantify the biomass of the whole plant had r2 of 70%. The density of the dried material was 0.92 g/cm3, obtaining an average dry wood weight of 44.8 kg per plant. This represents a content of 1682 moles of captured CO2 of a developed plant crop (3 years). The average ash on dry wood was 3%, fixed carbon content on dry wood was 7%, and volatile content dry wood was 78%. The moisture content of waste materials after pruning was 45.96%. The drying time in store for humidity below 10%, suitable for burning boiler, was 15 days. The higher heating value of peach wood was 18.92MJ/kg.

Landslides represent an important and possibly very dangerous natural hazard. Dendrogeomorphic methods can provide unique data on the behaviour of landslides in the past by studying the tree-ring series of disturbed trees. Knowledge about past landslide activity in the flysch part of the Outer Western Carpathians is generally very scarce or missing. The past activity of selected landslides (possibly endangering neighbouring settlements) was studied using data from 106 increment cores from 53 disturbed individuals of Picea abies (L.) H. Karst. to assess its past spatiotemporal activity. In total, six certain event years and 13 probable events were detected during the period between 1927 and 2017. Certain events always occurred in groups of the two following events, suggesting the inertia of landslide movements after the initial triggering. The spatiotemporal reconstruction revealed a distinctly increased activity of movements in the zone of the main scarp and particularly in the landslide front, which could possibly endanger human infrastructure during its significant reactivation. However, the reconstruction performed suggests general landslide inactivity since 1997, when the last high-magnitude reactivation occurred.

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The main aim of this research study is to assess the effect of plant spacing on vegetative development and crown morphometry of Bertholletia excelsa Bonpl. (Brazil nut) in the Peruvian Amazon. Two 16-year-old plantations with different initial spacings are examined by measuring the dasometric variables of 474 B. excelsa trees to calculate five morphometric crown indices. The results show that the highest vegetative development is found in trees with the smallest initial spacing. Diameter and height are negatively correlated with slenderness rate and salience index while coverage index and crown shape have a negative correlation with diameter. Tree development and crown morphometry of B. excelsa are significantly affected by initial spacing. In conclusion, plant spacing is an important parameter for establishing and managing B. excelsa plantations in the Peruvian Amazon. [ABSTRACT FROM AUTHOR]

Moringa oleifera is an introduced species grown in the Sudano-Sahelian zone of Far North Cameroon and highly sought after by the population because of its socio-economic importance and its potential for restoring degraded soils. In a perspective of its sustainable management, the present study aims to improve knowledge on the current structural state of this multipurpose species in this region in three sites (Diamaré, Mayo-Danay and Mayo-Tsanaga). A total of 144 records were inventoried in the 25 m * 25 m quadrats in an agricultural environment where M. oleifera is associated with crops for 48 records per site. The data measured in each quadrat are diameter, height and crown diameter. The calculated structural variables showed that the mean diameter ranged from 8.19 to 12.22 cm; the mean height from 4.1 to 5.30 m; an mean crown of 2.07 to 2.90 m, with an mean density between 978 and 1081 stems/ha; an mean basal area between 3.53 and 6.65 m²/ha for a coverage rate between 21.78 and 38.48 %. The demographic distribution of the population showed a predominance of individuals with a diameter between 5 and 10 cm for a height between 2 and 4 m and a crown lower than 2 m reflecting a young and exploited population. Statistical results showed a positive and significant correlation between diameter, height, and crown of M. oleifera (p= 0.0001). This work provides basic scientific information to serve as ecological indicators of the level of exploitation and sustainable management of this multi-purpose forest resource in the region. [ABSTRACT FROM AUTHOR]

Landslides represent an important and possibly very dangerous natural hazard. Dendrogeomorphic methods can provide unique data on the behaviour of landslides in the past by studying the tree-ring series of disturbed trees. Knowledge about past landslide activity in the flysch part of the Outer Western Carpathians is generally very scarce or missing. The past activity of selected landslides (possibly endangering neighbouring settlements) was studied using data from 106 increment cores from 53 disturbed individuals of Picea abies (L.) H. Karst. to assess their past spatiotemporal activity. In total, six certain event years and 13 probable events were detected during the period between 1927 and 2017. Certain events always occurred in groups of the two following events, suggesting the inertia of landslide movements after the initial triggering. The spatiotemporal reconstruction revealed a distinctly increased activity of movements in the zone of the main scarp and particularly in the landslide front, which could possibly endanger human infrastructure during its significant reactivation. However, the reconstruction performed suggests general landslide inactivity since 1997, when the last high-magnitude reactivation occurred. [ABSTRACT FROM AUTHOR]

Abstract Commercial height of the tree is a key variable for estimating the wood stock in tropical forests managed for timber production purposes. Most available measurement devices suffer limitations in this type of forest, promoting low precision measurements with high variation errors. The laser meter device appears as a viable alternative, as in addition to using trigonometric principles, it is not necessary that the device is close to the eyes of the meter to carry out the measurement. The device can be used to measure commercial height of trees on flat or sloping terrain, at different distances from the tree. However, there are no studies evaluating the precision of this device. The objective of this study was to determine the precision of the laser meter method for estimating the commercial height of trees, as compared to the actual measurement in a tropical forest in the Brazilian Amazon. Measurements were made on 300 trees with commercial height between 7 and 14 m. Actual commercial heights were measured with graduated ruler. Applied tests were paired t test, graphical analysis of residuals and calculations of bias statistics, mean absolute deviation, standard deviation of differences, and coefficient of determination (R2). Paired t test indicated that the mean of the heights measured by the laser meter is statistically equal to that of the graduated ruler. Measurements with laser meter did not show bias and had mean error of 0.0745. The standard deviation of the differences indicated dispersion of errors of 0.97, equal to that shown in the graduated rule. Laser meter presents an alternative method for estimating the commercial height of trees in tropical forest in the Brazilian Amazon. There was no tendency to underestimate or overestimate the commercial heights of trees. Use of the laser meter is potentially of use for measuring the commercial height of trees in tropical forests.

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The primary climatic characteristic of olive cultivation in Peru is the coastal desert environment with moderate temperatures, minimal precipitation, and high atmospheric water content during the winter season. This report presents a comprehensive study on water and carbon fluxes in a drip-irrigated olive orchard in Pisco Province, Peru, addressing the current lack of information on olive physiology and water management under these environmental conditions. The eddy covariance system installed in September 2019 showed an average ET of 2.18 ± 0.38 mm d−1, with seasonal variation. Drip irrigation was set at 60 m3 ha−1 d−1 during the growing season and reduced to half that amount in the winter. The study suggests that using deficit irrigation based on affordable dendrometry sensors could reduce water use by close to 30% while potentially preserving biomass gain and fruit yields. This could help improve water management in olive cultivation in coastal Peru. • Olive tree physiology is not well characterized for cool, damp, desert agriculture. • Carbon and water dynamics were studied combining eddy flux and biometric approaches. • Diurnal stem shrinkage patterns suggests significant tissue water storage in olive. • ET and dendrometry profiles show a biphasic pattern for tissue water replenishment. • WUE indicates irrigation water overuse through application of standardized setups. [ABSTRACT FROM AUTHOR]

ABSTRACT Allometric models defining the relationship between stem diameter and total tree height in the Amazon basin are important because they refine the estimates of tree carbon stocks and flow in the region. This study tests different allometric models to estimate the total tree height from the stem diameter in an ecotone zone between ombrophilous and seasonal forests in the Brazilian state of Roraima, in northern Amazonia. Stem diameter and total height were measured directly in 65 recently fallen trees (live or dead). Linear and nonlinear regressions were tested to represent the D:H relation in this specific ecotone zone. Criteria for model selection were the standard error of the estimate (Syx) and the adjusted coefficient of determination (R²adj), complemented by the Akaike Information Criterion (AIC). Analysis of residuals of the most parsimonious nonlinear models showed a tendency to overestimate the total tree height for trees in the 20-40 cm diameter range. Application of our best fitted model (Michaelis-Menten) indicated that previously published general equations for the tropics that use diameter as the independent variable can either overestimate tree height in the study area by 10-29% (Weibull models) or underestimate it by 8% (climate-based models). We concluded that our site-specific model can be used in the ecotone forests studied in Roraima because it realistically reflects the local biometric relationships between stem diameter and total tree height. Studies need to be expanded in peripheral areas of northern Amazonia in order to reduce uncertainties in biomass and carbon estimates that use the tree height as a variable in general models.

Knowledge of the pattern of exploitation of trees can help us understand the relationship between marmosets and plants, especially in declining forests, such as those in the Brazilian Cerrado. Black-tufted marmosets (Callithrix penicillata) regularly exploit exudates by gouging the bark of trees with their specialized teeth. Determining preferred tree species to exploit exudates is important for forest management aimed at maintaining an essential food source for urban marmosets. We characterized the tree species, dendrometry, and the characteristics of the holes made by marmosets to obtain exudates. Based on these data, we proposed a gouging effort index (Chiseling Suitability Index for Marmosets, ChiSI). We identified 16 species belonging to 10 families of trees with gouging marks made by marmosets. Eleven new tree species used by black-tufted marmosets for exudates were identified in urban forests in the Cerrado. Exudate exploration was predominantly of medium intensity, with round holes concentrated in the canopy. The species Tapirira guianensis and Croton urucarana were preferred. The ChiSI was characterized by a narrow range for both T. guianensis and C. urucarana. Despite the flexibility of obtaining exudates, the black-tufted marmosets concentrate their exploitation to only a few tree species. The T. guianensis and C. urucarana tree species should be considered the most important species for management plans and the preservation of black-tufted marmosets that live in urban forests in the Cerrado.

The development of new tools based on remote sensing data in agriculture contributes to cost reduction, increased production, and greater profitability. Airborne LiDAR (Light Detection and Ranging) data show a significant potential for geometrically characterizing tree plantations. This study aims to develop a methodology to extract walnut (Juglans regia L.) crowns under leafless conditions using airborne LiDAR data. An original approach based on the alpha-shape algorithm, identification of local maxima, and k-means algorithms is developed to extract the crowns of walnut trees in a plot located in Viver (Eastern Spain) with 192 trees. In addition, stem diameter and volume, crown diameter, total height, and crown height were estimated from cloud metrics and other 2D parameters such as crown area, and diameter derived from LiDAR data. A correct identification was made of 178 trees (92.7%). For structure parameters, the most accurate results were obtained for crown diameter, stem diameter, and stem volume with coefficient of determination values (R2) equal to 0.95, 0.87 and 0.83; and RMSE values of 0.43 m (5.70%), 0.02 m (9.35%) and 0.016 m3 (21.55%), respectively. The models that gave the lowest R2 values were 0.69 for total height and 0.70 for crown height, with RMSE values of 0.84 m (12.4%) and 0.83 m (14.5%), respectively. A suitable definition of the central and lower parts of tree canopies was observed. Results of this study generate valuable information, which can be applied for improving the management of walnut plantations.

Vegetation establishment, growth and succession in riparian ecosystems are linked to river flow dynamics and groundwater table fluctuations. This is especially true in Alpine gravel‐bed rivers with wide floodplains, geomorphically active floods and a strong river‐aquifer exchange. The role of short‐term groundwater fluctuations is not always clear in these ecosystems, as it is assumed that phreatophytic vegetation close to rivers is adapted to such conditions. Here, we provide data evidence of riparian plant response to short‐term groundwater table fluctuations in a braided gravel‐bed river (Maggia). We used indirect physiological variables for photosynthesis and transpiration—stomatal conductance gs and daily variation in stem diameter ΔDd—which we measured at six mature riparian trees of the Salicaceae family at two sites with different mean depths to groundwater during two growing seasons. The data demonstrate that (a) short‐term variation of the groundwater table affects riparian vegetation—at the site with deeper groundwater, the water table depth was the best predictor of gs variability, while at the site with shallower groundwater, temperature and vapour pressure deficit (VPD) were the best predictors of ΔDd variability; (b) instantaneous stomatal conductance is related to VPD, but conditioned by groundwater levels, with higher stomatal conductance for the same radiative input and VPD when the water table was higher for all trees; and (c) local microclimate measured at tree locations had a stronger predictive power for gs than valley scale climate, suggesting local climate controls on vegetated stands on gravel bars. Our results provide evidence of riparian trees undertaking physiological adjustments to transpiration in response to groundwater stage, depending on their riparian floodplain setting. [ABSTRACT FROM AUTHOR]

The objective of the study was to evaluate the productive efficiency of yerba mate regarding growth parameters, subjected to different conditions of cultivation, luminosity, and fertilization. The arboreal component entered to produce shade, corresponding to 60%, 45% and 30% of the light intensity. The luminosity levels were combined with different forms of fertilization: conventional fertilization (CF), controlled-release fertilization (CRF), and unfertilized (UF). The CF and CRF resulted in increase leaf area at 45% and 30% levels of luminosity. The dry weight of the leaves was 9.40% higher using CF, when compared to the unfertilized. Canopy diameter was less sensitive to variations in fertilization but significant in shading, in which the competition limit was described when submitted to 45% luminosity. The height of the yerba mate was homogeneous, and leaf biomass productivity displayed greater efficiency in 60% luminosity, without the use of fertilizer. CF promoted an increment of 8.67% in biomass productivity when under 45% apparent luminosity. [ABSTRACT FROM AUTHOR]

Commercial height of the tree is a key variable for estimating the wood stock in tropical forests managed for timber production purposes. Most available measurement devices suffer limitations in this type of forest, promoting low precision measurements with high variation errors. The laser meter device appears as a viable alternative, as in addition to using trigonometric principles, it is not necessary that the device is close to the eyes of the meter to carry out the measurement. The device can be used to measure commercial height of trees on flat or sloping terrain, at different distances from the tree. However, there are no studies evaluating the precision of this device. The objective of this study was to determine the precision of the laser meter method for estimating the commercial height of trees, as compared to the actual measurement in a tropical forest in the Brazilian Amazon. Measurements were made on 300 trees with commercial height between 7 and 14 m. Actual commercial heights were measured with graduated ruler. Applied tests were paired t test, graphical analysis of residuals and calculations of bias statistics, mean absolute deviation, standard deviation of differences, and coefficient of determination (R2). Paired t test indicated that the mean of the heights measured by the laser meter is statistically equal to that of the graduated ruler. Measurements with laser meter did not show bias and had mean error of 0.0745. The standard deviation of the differences indicated dispersion of errors of 0.97, equal to that shown in the graduated rule. Laser meter presents an alternative method for estimating the commercial height of trees in tropical forest in the Brazilian Amazon. There was no tendency to underestimate or overestimate the commercial heights of trees. Use of the laser meter is potentially of use for measuring the commercial height of trees in tropical forests. [ABSTRACT FROM AUTHOR]

We combined measurements of tree growth and carbon dioxide exchange to investigate the effects of selective logging on the Aboveground Live Biomass (AGLB) of a tropical rain forest in the Amazon. Most of the measurements began at least 10 months before logging and continued at least 36 months after logging. The logging removed ∼15% of the trees with Diameter at Breast Height (DBH) greater than 35 cm, which resulted in an instantaneous 10% reduction in AGLB. Both wood production and mortality increased following logging, while Gross Primary Production (GPP) was unchanged. The ratio of wood production to GPP (the wood Carbon Use Efficiency or wood CUE) more than doubled following logging. Small trees (10 cm < DBH < 35 cm) accounted for most of the enhanced wood production. Medium trees (35 cm < DBH < 55 cm) that were within 30 m of canopy gaps created by the logging also showed increased growth. The patterns of enhanced growth are most consistent with logging-induced increases in light availability. The AGLB continued to decline over the study, as mortality outpaced wood production. Wood CUE and mortality remained elevated throughout the 3 years of postlogging measurements. The future trajectory of AGLB and the forest's carbon balance are uncertain, and will depend on how long it takes for heterotrophic respiration, mortality, and CUE to return to prelogging levels.

Diameter fluctuations of branches, shoots, or fruits are related to plant transpiration and water potential. In the past, several models have related dendrometric variables and evapotranspiration on a daily scale. However, trunk–branch shrinkage occurs only between dawn and midday, while evapotranspiration occurs most of the day from sunrise to sunset. Previous models have failed to incorporate this key fact. The objective of the present study was to assess the relationship of hourly daily shrinkage (HDS) between dawn and the next 4 h to the hourly reference evapotranspiration (EToh) of the same period in walnut trees and pomegranate plants under different irrigation regimes. Our data show that the relationship between EToh and HDS is much better than several previous models that included maximum daily shrinkage (MDS) and reference evapotranspiration (ETo). The novel slope analysis of the relationship between HDS versus time used here corresponds to the velocity at which the HDS occurs, which depends on the ETo intensity at that moment. This new method of analyzing this type of data calls for a revision of these models and sets a new baseline for future analysis.

Living trees constitute one of the major stocks of carbon in tropical forests. A better understanding of variations in the dynamics and structure of tropical forests is necessary for predicting the potential for these ecosystems to lose or store carbon, and for understanding how they recover from disturbance. Amazonian tropical forests occur over a vast area that encompasses differences in topography, climate, and geologic substrate. We observed large differences in forest structure, biomass, and tree growth rates in permanent plots situated in the eastern (near Santarém, Pará), central (near Manaus, Amazonas) and southwestern (near Rio Branco, Acre) Amazon, which differed in dry season length, as well as other factors. Forests at the two sites experiencing longer dry seasons, near Rio Branco and Santarém, had lower stem frequencies (460 and 466 ha(-1) respectively), less biodiversity (Shannon-Wiener diversity index), and smaller aboveground C stocks (140.6 and 122.1 Mg C ha(-1)) than the Manaus site (626 trees ha(-1), 180.1 Mg C ha(-1)), which had less seasonal variation in rainfall. The forests experiencing longer dry seasons also stored a greater proportion of the total biomass in trees with >50 cm diameter (41-45 vs 30% in Manaus). Rates of annual addition of C to living trees calculated from monthly dendrometer band measurements were 1.9 (Manaus), 2.8 (Santarém), and 2.6 (Rio Branco) Mg C ha(-1) year(-1). At all sites, trees in the 10-30 cm diameter class accounted for the highest proportion of annual growth (38, 55 and 56% in Manaus, Rio Branco and Santarém, respectively). Growth showed marked seasonality, with largest stem diameter increment in the wet season and smallest in the dry season, though this may be confounded by seasonal variation in wood water content. Year-to-year variations in C allocated to stem growth ranged from nearly zero in Rio Branco, to 0.8 Mg C ha(-1) year(-1) in Manaus (40% of annual mean) and 0.9 Mg C ha(-1) year(-1) (33% of annual mean) in Santarém, though this variability showed no significant relation with precipitation among years. Initial estimates of the C balance of live wood including recruitment and mortality as well as growth suggests that live wood biomass is at near steady-state in Manaus, but accumulating at about 1.5 Mg C ha(-1) at the other two sites. The causes of C imbalance in living wood pools in Santarém and Rio Branco sites are unknown, but may be related to previous disturbance at these sites. Based on size distribution and growth rate differences in the three sites, we predict that trees in the Manaus forest have greater mean age (approximately 240 years) than those of the other two forests (approximately 140 years).

The new method for evaluation of tree populations presented here is based on a correlation analysis within a set of dendrometric variables. The correlation analysis is carried out for each population separately. The method evaluates differences between resulting correlation matrices. These distances can be used by hierarchical cluster analysis (unweighted pair-group average) or by ordination analysis (non-metric multidimensional scaling - NMS). Test data were obtained in 10 research plots in the area of Medvědí Mt., Šumava National Park. Plots are located in Norway spruce [Picea abies (Linnaeus) H. Karsten] climax forests. The results enable ecological interpretation of both classification and NMS. The populations (subpopulations) differ in their origin (spontaneous succession or partial planting) and environmental conditions (extreme environment near the mountain summit versus water-logged soils). These differences were reflected in results of the classification and ordination of the spruce (sub)populations.

ABSTRACT Buttresses and other natural structures modify the shape of stems in Amazonia and change the diameter at breast height (DBH) measured at 1.3 m at ground level. The lack of adequate measurement techniques affects negatively forest dynamics analyses and biomass estimating. The study evaluated an indirect method of measuring diameters in trees with DBH > 40 cm using principles of digital photogrammetry. The results obtained with two cameras (smartphone and Sony) were compared with direct measurements using diametric tape and a ladder. The technique is adequate to measure the diameters of trees with measurement point above 2 m of ground, with a confidence interval of ±1cm. The use of photogrammetry as a supplementary tool to the diametric tape (IC ± 0.24 cm) is recommended, helping to measure trees with diameter above the reach of the technician in forest inventories.

The mahogany tree (Swietenia macrophylla King) is a species of conservation concern, mostly due to illegal and destructive harvesting practices. It has been planted in several agroforestry systems in the Brazilian Amazon to preserve the species and provide a sustainable source of this valuable timber. This study analyzed the growth and yield of the mahogany wood from plants used as shading in cocoa-based agroforestry systems with nitisols and red–yellow acrisols, located in the State of Pará, in the Brazilian Amazon, because these two types of soils are the most recommended for implanting cocoa-based agroforestry systems in the region due to their natural fertility. The installed experiment was a randomized 2 × 6 factorial experiment, with two types of soil and six different tree ages. The results indicate that soil type and plant age both affected the increments in diameter at breast height. Trees from the red–yellow acrisol had statistically higher diameter at breast height values (P < 0.05) than trees from the nitisol (40.05 and 33.57 cm, respectively). There was also a significant interaction between soil type and tree age (P < 0.01). The average stem height differed markedly between the soil types from plants aged 19 and 22 years (P < 0.05), whereas average stem height differed significantly among the 16-, 19-, and 22-year-old plants (P < 0.05). The average wood volume was 1.41 m3 tree−1, and the highest yield (1.75 m3 tree−1) was achieved in the red–yellow acrisol site, for 33-year-old trees. These results demonstrate how the cocoa and mahogany-based agroforestry systems can produce these products in a sustainable manner in the Brazilian Amazon. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the adjustment of taper models with and without bark for clone GG100 in a commercial plantation located in the southern state of Tocantins. Twenty-five trees were cubed in which data were fitted five taper models, three of which were the most used in Brazil and two representing the poorly tested models in the country. In the evaluation of the taper models, the following statistical criteria were adopted: standard error of the estimate, adjusted coefficient of determination, mean deviation, sum of squares of the relative residue, percentage residue, and analysis of the distribution of residues. It was concluded by an exponent-shape type model to describe the trunk profile with and without bark of individual clones of clone GG100. [ABSTRACT FROM AUTHOR]

Global warming has become international concern, culminating with the ratification of the Kyoto Protocol which includes definitions and objectives of the sustainable development mechanisms and features that make it easier for the industrialized countries to jointly compensate for their polluting greenhouse gas emissions. São Paulo is a state known for its industrial development and distortion of the green areas in ecosystems associated with the Atlantic Forest biome. In the middle of this chaotic scenery lies the Billings reservoir in São Bernardo do Campo-SP, its forest ecosystem is the provider of numerous environmental services. Quantification of biomass (Bwood) of stems resulted in estimates of 113.73.ha-1, which corresponded to 56.87 tC.ha-1. The estimates obtained for the forest ecosystem of the reservoir can be used as a reference for the establishment of forest restoration projects under the under the sustainable development mechanism established the Kyoto Protocol. [ABSTRACT FROM AUTHOR]

The sustainable agriculture of forest plantations demands the permanent monitoring of the quantity of processed wood, thus becoming difficult to monitor large planted areas by using only manual procedures. Therefore, in this research artificial neural networks (RNA) of multilayer perceptrons, were modeled to estimate the spatial of wood volume in a Eucalyptus-sp plantation located in the state of Mato Grosso del Sur in the Central-West region of Brazil. As input variables in the RNA spectral bands, the textures of the bands obtained with Gray Level Co-occurrence Matrices and vegetation index were used, which were derived from digital satellite image Spot 6. The resulting RNA with the best performance presented accuracy of 93.32% and coefficient of determination of 0.9761. However, this network presented a mean square error of 16.32% (RMSE de 7.85 m³ha-1), but with a unbiased distribution of the residuals. So, the model showed to be suitable to monitor the amount of wood in large areas without overestimating or underestimating the prediction. Compared with different machine learning methods using the same variables, the built network seems to have a higher precision and accuracy. Even in the neuronal models using only spectral bands and vegetation indexes, a better performance was evidenced, showing that the textures contribute in the improvement of predictions. [ABSTRACT FROM AUTHOR]

Abstract A dendrometric and energetic characterisation of Tamarix africana L. was carried out in this study. This is an indigenous plant species in the Mediterranean area, and it can survive in semi-arid areas with saline soils and occasional floods. Owing to these characteristics, this species is a good candidate for its use in the restoration of several environments, such as the marshes. This opens up the possibility of improving the management of biomass, which can be used for obtaining economic benefits from its energetic use. For the stems, biomass volume functions were determined from their diameter and length with r2 of 0.96. For the whole plant, biomass volume functions were determined from the diameter of the projected area in the soil and the height of the plant with r2 of 0.95. For energetic characterisation, the density, higher heat value, and the composition of this wood were measured in terms of following elements: carbon, nitrogen, hydrogen, sulphur and chlorine, volatiles and ash. The determination of its composition in C allows us to evaluate the CO 2 fixed by the plant during its growth. The average catchment was estimated to be 2.58 kg/plant. Highlights • Dendrometric analysis has been carried out of Tamarix africana. • It has become the elemental, proximate and structural analysis. • Models for predicting higher calorific have been evaluated. [ABSTRACT FROM AUTHOR]

The objective of this work was to perform a complete evaluation of using biomass from pruning residues of ficus trees ( Ficus benjamina ), widely grown as ornamental plants in cities in Ecuador. Due to their great capacity for propagation and fast growth, these trees need frequent pruning and so generate a large amount of ligneous residues. A dendrometric analysis of the plant was performed to calculate the quantity of residues generated from easily measurable variables, such as crown diameter and plant height. The models obtained gave a coefficient of determination of R 2 = 0.75. Pruning residues included mixtures of wood and leaves. The percentages of leaf and woody biomass were measured and a calorific analysis, elemental analysis, proximal analysis and structural analysis of the different mix proportions were carried out. Nitrogen content was acceptable for use as biofuel. Ash content in the wood is 5%, but the inclusion of leaves in the sample increases the ash content up to 11% when the leaf percentage is greater than 50%. About 10 kg of material, on average, was obtained from each tree. The mean calorific value of these residues was 19 MJ kg −1 and was influenced by the volatile content and lignin. [ABSTRACT FROM AUTHOR]