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Increased frequency and intensity of storms, sea level rise, and warming temperatures are affecting forests along the eastern coast of the United States. However, we lack a clear understanding of how the structure of coastal forests is being altered by climate change drivers. Here, we used data from the Forest Inventory and Analyses program of the US Forest Service to examine structure and biomass change in forests along the mid-Atlantic, Southeastern, and Gulf coasts of the US. We selected plots that have been resampled at low (5 m) and mid (30–50 m) elevations in coastal areas of states from Texas to New Jersey, allowing us to determine change in live trees, standing dead wood, and downed dead wood biomass (and carbon) stocks across a decade at the county level. Forest area increased by 1.9% and 0.3% in low and mid elevation counties, respectively. Live tree biomass density increased by 13% and 16% in low mid elevation counties, respectively. Standing dead biomass decreased by 9.2% and 2.8% in low and mid elevation counties, respectively. Downed dead wood increased by 22% in low elevation counties and decreased 50% in mid elevation counties. Annualized growth and harvest were both higher (16% and 58% respectively) in mid elevation than low elevation counties, while annualized mortality was 25% higher in low elevation counties. Annualized growth in low elevation counties was negatively correlated to sea level rise rates, and positively correlated to number of storms, illustrating tradeoffs associated with different climate change drivers. Overall, our results illustrate the vulnerability of US coastal low and mid elevation forests to climate change and sea level rise, with indications that the complexity and rate of change in associated ecosystem functions (growth, mortality, and carbon storage) within the greater social environment (agricultural abandonment) may increase. [ABSTRACT FROM AUTHOR]

Veteran and ancient trees are key structures sustaining biodiversity in wooded landscapes. Their value depends on tree‐related microhabitats (TreMs) such as hollows, cracks and other structures related to wounds and wood decay. Decline and loss of veteran trees results in the loss of TreMs thus threatening the biodiversity associated with them.Veteranisation, that is, interventions aimed at creating or accelerating formation of rare TreMs in live trees, are thus increasingly applied to bridge gaps in habitat continuity and sustain the biodiversity associated with veteran trees. Several studies investigated the use of artificially created TreMs by various organisms. No study has, however, investigated saproxylic beetles attracted to freshly veteranised trees, and how different veteranisation techniques affect attractivity of veteranised trees to saproxylic beetles.We veteranised 48 sessile oaks using two types of deep and two types of shallow cuts and trapped saproxylic beetles on the veteranised and control trees in the first season after the intervention. The sampling yielded 280 species (6171 individuals) of saproxylic beetles, including 64 that are threatened. Veteranised trees attracted more abundant and diverse communities than control trees. Community composition differed between shallow and deep cuts and between the two types of deep cuts.Freshly veteranised trees thus attract diverse and abundant communities of saproxylic beetles consisting mainly of species potentially exploiting the wounds. The high proportion of threatened species, often associated with old oaks, suggests that veteranised trees benefit even some threatened saproxylic biodiversity already during the first year after the veteranisation. [ABSTRACT FROM AUTHOR]

Traditional clear-cutting of even-aged plantations has become less desirable, with forestry shifting towards more diverse, multi-purpose integrated forest management. This study compared easily selected forest structures in managed forests and forest reserves to guide integrated forest management. The study area includes six managed forest areas and six forest reserves, with management types compared over approximately 50 years. The evaluated areas are part of the university forests of Mendel University in Brno, covering approximately 30 km² of natural deciduous temperate forests, predominantly composed of sessile oak and European beech. A total of 599 inventory plots were surveyed, assessing the presence or absence of selected forest structures in six categories. Twelve logistic generalized mixed models were developed to estimate the probability of occurrence of the observed forest structures based on their management status. Significant differences were found in the categories of dead standing and lying wood, microhabitat trees, and non-native tree species, with all variables showing a higher probability in forest reserves compared to managed forests. The results support the shift towards integrative management by incorporating elements of retention forestry. However, certain variables, such as natural regeneration and species diversity, showed little variation between management types, suggesting that some forest attributes are resilient to management practices. • Easy and quick set of forest structures to compare managed and unmanaged forests. • Differences in a short period (50 years) since management abandonment. • Big differences in dead wood, microhabitat trees, non-native trees between management types. • No differences in natural regeneration and species diversity between management types. [ABSTRACT FROM AUTHOR]

Forests have the potential to contribute significantly to global climate policy efforts through enhanced carbon sequestration and storage in terrestrial systems and wood products. Projections models simulate changes future in forest carbon fluxes under different environmental, economic, and policy conditions and can inform landowners and policymakers on how to best utilize global forests for mitigating climate change. However, forest carbon modeling frameworks are often developed and applied in a highly disciplinary manner, e.g., with ecological and economic modeling communities typically operating in silos or through soft model linkages through input–output parametric relationships. Recent disciplinary divides between economic and ecological research communities confound policy guidance on levers to increase forest carbon sinks and enhance ecosystem resilience to global change. This paper reviews and summarizes the expansive literature on forest carbon modeling within economic and ecological disciplines, discusses the benefits and limitations of commonly used models, and proposes a convergence approach to better integrating ecological and economic systems frameworks. More specifically, we highlight the critical feedback loops that exist when economic and ecological carbon models operate independently and discuss the benefits of a more integrated approach. We then describe an iterative approach that involves the sharing of methodology, perspectives, and data between the regimented model types. An integrated approach can reduce the limitations or disciplinary bias of forest carbon models by exploiting and merging their relative strengths. [ABSTRACT FROM AUTHOR]

Agroforestry is an alternative land use practice that holds promise for societal benefits and the attainment of ecosystem sustainability. The objectives of this study were to evaluate the tree diversity, carbon sequestration, soil carbon pool, oxygen production and rice productivity under traditional agroforestry systems at different elevations in the Garhwal Himalayan region of India. Tree diversity, carbon sequestration and oxygen production were quantified by field measurements (using 0.04 ha quadrats) and subsequent calculations. Rice productivity was assessed using grain yield, straw yield and biological yield, while soil properties were analyzed in the laboratory using standard methods. Results of the study showed that tree diversity was higher at the 1200–1600 m elevation and had a maximum Shannon Diversity Index (1.29) and Simpson Diversity Index (0.69). The 1600–2000 m elevation stored more carbon (34.43 Mg ha−1) and total oxygen production (91.79 Mg ha−1). Among the agroforestry trees, Quercus leucotrichophora, Melia azedarach and Prunus cerasoides showed the highest carbon storage and total oxygen production. Elevation and soil depth were found to affect the soil properties. The agroforestry systems had higher soil organic carbon and lower bulk density than sole cropping systems. Compared to the agroforestry system, the monoculture produced more rice (Oryza sativa). The study shows that traditional agroforestry is a valuable tool for carbon sequestration and soil improvement, albeit with potential compromises in crop productivity. It emphasises the need for tailored management approaches to harness the ecological and environmental benefits of agroforestry in the Himalayas. This study draws attention to the potential of traditional agroforestry in the Garhwal Himalaya for carbon sequestration, climate change mitigation and soil quality improvement which provides a reference for striking a balance between the ecological advantages of agroforestry and the socio-economic considerations of local communities. However, it also underlines the importance of considering trade-offs between environmental benefits and crop yields when implementing such agroforestry systems. Highlights: • Elevation plays an important role for tree diversity, net carbon sequestration and net oxygen production in Himalaya. • Compared to sole cropping system, agroforestry systems had higher soil pH and soil organic carbon, along with lower bulk density. • Production was high in sole cropping system while agroforestry had ecological benefits like carbon storage and soil improvement. [ABSTRACT FROM AUTHOR]

Background: Prescribed burning is an important fuel management tool to prevent severe wildfires. There is a pressing need to increase its application to reduce dry fuels in the western United States, a region that has experienced many damaging wildfires. Public support for this practice is tempered by concern around smoke impacts and escape risks. This study aims to understand how recent experiences with wildfire smoke and perceived risk of smoke events affect public support for prescribed burning. Methods: Data were from the May 2023 Household Emergency Preparedness Survey, an online panel survey of 1,727 adults in 12 western conterminous states, applying survey weights to reflect the underlying population demographics. In weighted logistic regression models, we evaluated associations between predictor variables (past experiences with smoke, wildfire risk perception) and support for prescribed burns in general or near a respondent's neighborhood, adjusting for age, race/ethnicity, gender, education, household income, and wildland urban interface status. Mediation models were used to assess whether perceived risk of smoke exposure mediates the relationship between recent smoke experience and support for prescribed burning. Results: Approximately two-thirds of the population supported prescribed burning in general, and more than half supported prescribed burning near their neighborhood. 44% reported experiencing a smoke event in the past 3 years, which increased the odds of support for prescribed burning in general (OR = 2.03, 95%CI 1.51–2.74) and near their neighborhood (OR = 1.59, 95% CI 1.20–2.09). High perceived risk of future smoke impacts was associated with support for prescribed burns in general (adjusted OR = 1.66, 95% CI = 1.15–2.39) and near their residence (adjusted OR = 1.72, 95%CI = 1.23–2.39). Although only trending towards significance, perceived future risk mediated 16.9% (p = 0.066) of the association between recent smoke experience and support for prescribed burning nearby. Among those who experienced recent smoke events, reporting high degrees of overall smoke impacts or outdoor air quality impacts were positively associated with support for prescribed burns. Conclusions: Recent experience with wildfire smoke and perceived future risk are strongly associated with support for prescribed burns. Educational campaigns can apply these findings to improve public support toward prescribed fire activities and funding to reduce wildfire risks and protect public health. [ABSTRACT FROM AUTHOR]

Background: Mutualistic mycorrhiza fungi that live in symbiosis with plants facilitates nutrient and water acquisition, improving tree growth and performance. In this study, we evaluated the potential of mutualistic fungal inoculation to improve the growth and disease resistance of Scots pine (Pinus sylvestris L.) against the forest pathogen Heterobasidion annosum. Results: In co-inoculation experiment, Scots pine seedlings were pre-inoculated with mutualistic beneficial fungus (Suillus luteus) prior to H. annosum infection. The result revealed that inoculation with beneficial fungus promoted plant root growth. Transcriptome analyses revealed that co-inoculated plants and plants inoculated with beneficial fungus shared some similarities in defense gene responses. However, pathogen infection alone had unique sets of genes encoding pathogenesis-related (PR) proteins, phenylpropanoid pathway/lignin biosynthesis, flavonoid biosynthesis, chalcone/stilbene biosynthesis, ethylene signaling pathway, JA signaling pathway, cell remodeling and growth, transporters, and fungal recognition. On the other hand, beneficial fungus inoculation repressed the expression of PR proteins, and other defense-related genes such as laccases, chalcone/stilbene synthases, terpene synthases, cytochrome P450s. The co-inoculated plants did not equally enhance the induction of PR genes, chalcone/stilbene biosynthesis, however genes related to cell wall growth, water and nutrient transporters, phenylpropanoid/lignin biosynthesis/flavonoid biosynthesis, and hormone signaling were induced. Conclusion: S. luteus promoted mutualistic interaction by suppressing plant defense responses. Pre-inoculation of Scots pine seedlings with beneficial fungus S. luteus prior to pathogen challenge promoted primary root growth, as well as had a balancing buffering role in plant defense responses and cell growth at transcriptome level. [ABSTRACT FROM AUTHOR]

Numerous studies have reported that observed species shifts in mountain areas lag behind expectations under current warming trends, however, the mechanisms remain poorly understood. One important mechanism might be microclimatic heterogeneity causing migration of species to cooler conditions under closed forest canopies, but evidence is scarce. We here compared the distributions of 710 species (11 taxonomic groups including fungi, plants, and animals) along an elevation gradient (287–1419 m a.s.l.) in a temperate low mountain range between 2006–2008 and 2016–2017 to address this open question. We characterized each species' distribution (peak and breadth) based on their abundance along two environmental gradients: elevation and canopy cover. We then analysed changes in species' distribution peaks, asking whether shifts in canopy distribution and initial distribution characteristics explain variation in elevational distribution shifts. Across all taxa, the mean shift in elevational distribution peak was + 35.3 m (i.e. upslope). Species' baseline distribution peaks were strong predictors of elevational distribution shifts with stronger upslope shifts in low‐elevation and open‐forest species. Even though we observed considerable variation in the responses among species, canopy distribution shifts had a significant negative effect on elevational distribution shifts overall and in six taxonomic groups. We suggest that this is related to cooler microclimatic conditions under closed compared to open forest canopies. Shifts to closed‐canopy forests may thus partly compensate for elevational distribution shifts, highlighting the conservation value of heterogeneous landscapes featuring microclimatic refugia. Yet, it is likely that other mechanisms, such as habitat limitation, are also at play. Future studies need to quantify the potential of microclimatic refugia under accelerating forest dynamics, considering the interplay of canopy cover and other factors driving microclimate, and to illuminate the complex climate change response mechanisms among species and taxonomic groups. [ABSTRACT FROM AUTHOR]

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Forest ecosystems are one of the largest terrestrial carbon (C) reservoirs on Earth and an important sink of anthropogenic CO2 emissions. Abiotic and biotic disturbances such as windfalls, fires, outbreaks of insects or pests may negatively affect C storage in forest ecosystems decreasing their role as CO2 sink. The objective of this review was to summarize the current knowledge on the impact of large-scale forest ecosystem disturbances caused by windthrow and insect outbreaks on soil C stocks and cycles, and to gather information on the impact of restoration treatments performed in disturbed stands in the context of carbon accumulation in forest soils. Discussed were effects of windstorms and insect outbreaks as well as impacts of various approaches of forest regeneration after disturbance on C stocks and fluxes. Disturbances decrease C stocks in forest ecosystems and turn them from C sink into C source for a certain time. Regeneration of the disturbed forest restores its role as a CO2 sink. In montane forests artificial afforestation seems to shorten the time of achieving C parity. However, no data exists for lowland forests. Hence, there is an urgent need for studies that assess effect of windfalls and insect outbreaks on carbon storage in forests of lowland Europe. [ABSTRACT FROM AUTHOR]

Understanding the nutritional ecology of orchids, particularly those in symbiosis with rhizoctonias, presents a complex challenge. This complexity arises partly from the absence of macroscopic fruit bodies in rhizoctonias, which impedes the acquisition of their stable isotope data. In this study, we investigated the fungal associations and isotopic signatures in the pelotons of Stigmatodactylus sikokianus (associated with non-ectomycorrhizal [non-ECM] rhizoctonias) and Chamaegastrodia shikokiana (associated with ECM rhizoctonias). Our research reveals elevated levels of 13 C enrichment in S. sikokianus plants and their pelotons, similar to those found in fully mycoheterotrophic orchids and their mycobionts. Interestingly, C. shikokiana plants and their pelotons exhibited even higher levels of 13 C and 15 N enrichment than many other fully mycoheterotrophic species. Our findings imply that both ECM and saprotrophic mycobionts, including certain rhizoctonias, can fulfill the carbon needs of highly mycoheterotrophic orchids. This finding also indicates that 13 C enrichment can be an indicator of mycoheterotrophy in at least some rhizoctonia-associated orchids, despite the typically low 13 C enrichment in non-ECM rhizoctonias. Our demonstration of partial mycoheterotrophy in S. sikokianus suggests a broader prevalence of this nutritional strategy among orchids, given that almost all orchids are associated with non-ECM rhizoctonias., (© 2024 John Wiley & Sons Ltd.)