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Climate change has significantly impacted the wildfire regimes in lodgepole pine forests, resulting in prolonged fire seasons and altered fire behaviour. In North America, fire patterns have shifted towards more frequent and severe wildfires after a century of fire suppression. In response, silviculture practices in fire-prone areas should aim to restore diverse forest structures that are resistant or resilient to wildfires. In Western Canada, where forestry is a key industry, interest in seeking silvicultural solutions for promoting forest resilience to wildfires has increased following the devastating wildfire seasons between 2017 and 2023. Irregular shelterwood, a silvicultural system with a relatively short history of implementation in British Columbia, has been deployed in ecologically sensitive areas to promote structural heterogeneity and meet management goals for biodiversity and wildlife values. Although the impacts of irregular shelterwood on wildlife habitat and abundance have been well studied, the interaction between wildfire and the stand structure created by irregular shelterwood remains poorly understood. To understand the effectiveness of the irregular shelterwood in building wildfire resilience, we present a study of a lodgepole pine stand that was treated with irregular shelterwood and partially burned in a wildfire in 2017. This study collected ground fuel, canopy fuel, and tree data from four stand types (irregular shelterwood treated-burnt, treated-unburnt, untreated-burnt, and untreated-unburnt) and analyzed the difference in char height and fire-induced mortality between burnt and unburnt conditions, with irregular shelterwood treatment being a variable. The results demonstrated reduced wildfire effect in the irregular shelterwood stand in this region of British Columbia. This observation was made at a stage where the openings have not been colonized by regeneration. This case study provides valuable insights into the effectiveness of irregular shelterwood in mitigating wildfire risk, and proposes a potential silviculture solution to promote forest resilience to wildfire. [ABSTRACT FROM AUTHOR]

Forest restoration thinning may accelerate the development of structural complexity toward old-growth conditions faster than a natural forest, yet associated changes in forest carbon (C) are poorly understood. Old-growth forests are characterized by high levels of sequestered C in aboveground biomass and soil C pools, yet active management has well-recognized negative impacts on stored C. Effects of forest restoration thinning on forest C can be determined using longitudinal measurements and modeling based on stand conditions and tree growth. At Ellsworth Creek Preserve in Southwest Washington, forest restoration efforts in a second-growth temperate rainforest have been monitored using permanent plots since 2007. Here, we compare repeat measurements from 2020, modeled forest C, and measurements of O-horizon C pools from 2022 to determine C impacts of silvicultural treatments for old-growth restoration. We found good general agreement between empirical measurements and models of forest C using the Forest Vegetation Simulator (FVS). However, treatment alone was not a strong indicator for C conditions; rather, forest age and age–treatment interactions better predicted soil C responses to restoration treatments. These data may indicate that "light" forest restoration thinning can accelerate old-growth development with minimal effects on soil carbon—a win-win conservation strategy for old-growth forests and the climate. [ABSTRACT FROM AUTHOR]

As the Anthropocene tightens its grip on the world, forests are facing escalating disturbance rates, tree mortality, degradation and risks of catastrophic collapses. A popular and controversial proposition is to enhance forests' response diversity by adding novel tree species with missing functional traits through forest assisted migration (FAM). Beyond tests of the survival and growth of southern species or provenances in colder regions and studies of the socio-ecological challenges facing FAM, little interest has been paid to the silvicultural system for FAM implementation. Yet, the topic could influence its biological success, social acceptability, and economic feasibility. For example, southern light-intolerant tree species introduced into northern uneven-aged forests may experience a lack of light availability. Likewise, implementing FAM in clearcuts raises social acceptability issues. The patch-cut system combines advantages of even- and uneven-aged systems useful for FAM; however, perhaps due to the difficulty of its operationalization, it is rarely used. We propose a new way to implement the patch-cut system, enabling from the get-go to plan the location and timing of treatment of each patch in a stand. We discuss the advantages that this revisited patch-cut system presents for FAM: (i) the testing of various planting environments, (ii) easy monitoring in an adaptative management context where each patch is a replicate of a repeated-measure experiment and (iii) low intensity planting for efficient future dispersion of species adapted to a changing climate. We end with a call for the development of an international network of FAM trials within the revised patch-cut system. [ABSTRACT FROM AUTHOR]

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In recent decades, ungulates have expanded in number and range in Europe. This review aims to analyze the impact of ungulate browsing in different forest ecosystems and identify the main driving factors and trends. In total, 155 studies were analyzed in preparing this review, across 19 European countries. In Europe, the main browsers are represented by roe deer (Capreolus capreolus L.), red deer (Cervus elaphus L.), moose (Alces alces L.), chamois (Rupicapra rupicapra L.), and fallow deer (Dama dama L.). Regarding browsing severity, they frequently exceeded 50%, meaning that over half of the saplings were browsed. Ungulate density was the main driving factor of browsing severity, with areas exhibiting high browsing pressure often having more than ten individuals per square kilometer. The type of silvicultural system used played a vital role in the severity of browsing, and trends in foraging for preferred tree species were identified. Fencing was the most common non-harmful protection method used, while hunting management was the most efficient method for controlling deer numbers and browsing intensity. Large carnivores were missing in most study areas, but in the areas where they were present, they played a significant role in creating a chain reaction of ecological impacts. Considering the significant impact of ungulate browsing on forest ecosystems, there is a pressing need for more research to comprehend and effectively mitigate the effects of deer presence comprehensively. [ABSTRACT FROM AUTHOR]

The article focuses on the impact of social dynamics on modern silvicultural treatments, emphasizing how forest management has evolved with changing societal values. Topics include the shift from commercial objectives to ecosystem services, the challenges of reconciling urban and rural perceptions of forests, and the influence of climate change and natural threats on forest management practices.

Streamside management zones (SMZs) are regulated components of actively managed forests in the eastern United States, but width and overstory retention requirements vary widely among states. Within watershed-scale harvests, we evaluated the relative abundances of three riparian-associated songbirds (Acadian flycatcher, Empidonax virescens ; blue-headed vireo, Vireo solitarius ; and Louisiana waterthrush, Parkesia motacilla) near Appalachian headwater streams receiving three SMZ treatments representative of a range of current state SMZ regulations in the eastern United States. Prior to harvest, all species were relatively abundant near all stream types, including ephemerals. Abundances of all species were largely similar among SMZ treatments at 3 years and 10 years postharvest and were higher along streams with greater residual canopy cover within 100 m. Forested SMZs as prescribed by current regulations can sustain these species in managed forests up to 10 years postharvest, but abundance appears to be driven largely by canopy cover retention in adjacent stands. Managing habitat for riparian-associated songbirds in harvested watersheds will require expanding the extent of focus beyond the local stream corridor to include consideration of silvicultural systems that retain greater canopy cover in surrounding forests. Where conservation of riparian-associated songbirds is a management objective, SMZ protection should be extended to all streams. Study Implications: The results of this study suggest that forested streamside management zones (SMZs) mandated by contemporary best management practices (BMPs) in Kentucky and other eastern US states can sustain similar abundances of three riparian-associated songbirds in managed watersheds up to 10 years after harvest. Overstory retention in SMZs along perennial and intermittent streams is common across the eastern United States, but state BMPs rarely require retention along ephemeral streams. Target songbird species occupied forests along all stream types prior to harvest, and their postharvest abundances were positively associated with canopy retention within 100 m of streams. If long-term occupancy of managed stands by riparian-associated songbirds is an objective, we recommend using SMZs around all streams, including ephemerals, and implementing at least moderate-retention silvicultural systems in areas within 100 m of streams. [ABSTRACT FROM AUTHOR]

Aims: To improve soil phosphorus (P) testing in silvicultural systems, we assess microdialysis to study concentrations and establish a standard methodology to assess soil diffusive P and in-vivo translocated sap flow P under variable rates of P carryover from a previous rotation across various soils. Methods: Soils were collected from each treatment in the field and analyzed in laboratory conditions. Soils were analyzed for diffusive soil P using microdialysis and Mehlich III for comparison. Sap flow P measurements were collected in the field from 16 trees, one tree per treatment and replication over four hours. Results: Spodosol soils had higher diffusive P levels than Alfisol soils. On average, diffusive P increased by 137% in Spodosol and 166% in Alfisol from pre- to post-planting of a new stand. In the Alfisol, diffusive P showed a strong relationship with tree height, while no significant association was observed in the Spodosol. The Mehlich III soil extractions were positively related to the Alfisol but not the Spodosol. Microdialysis samples collected from the trees responded to changes in fertilization rates and were shown to be positively related to tree heights and Mehlich soil P tests. Atmospheric conditions substantially impacted sap flow P, with samples collected in full sunlight showing an average increase of 100% compared to overcast conditions. Conclusions: These findings demonstrate the potential of microdialysis as a valuable tool for soil P testing and its application in addressing complex questions related to P translocation and tree physiology in silvicultural settings. [ABSTRACT FROM AUTHOR]

In northern British Columbia and southern Yukon woodland, caribou forage extensively on terrestrial lichens, predominately mat-forming Cladina species in late-successional pine-lichen woodlands. Many of these stands are now reaching a point in their development where lichen abundance declines as feather-moss mats increase. We evaluated the response of forest floor plant communities in pine-lichen woodlands from the southern Yukon Lewes Marsh partial-cutting trial 8 years after harvesting. Photoplot results documented a major decline (>60% ± 5.6% SE) in the mean surface area of existing large clumps of C. mitis in control (unharvested) treatments, whereas the mean surface area of large C. mitis clumps declined by 28% (±15% SE) in the one-third basal-area removal and showed an increase of 13.5% (±25% SE) in the two-thirds basal-area removal. Line intercept transects documented no changes in overall stand-level lichen abundance between pre-harvest (2012) and post-harvest (2021) measurements, while feather-moss mats and dwarf shrubs showed declines and increases, respectively, in partial-cutting harvest plots. Stand thinning may provide a bridging strategy to extend the period of forage lichen availability in late-seral pine-lichen woodlands, an important consideration in landscapes where increasing severity and frequency of fires are changing the seral-state distribution of caribou habitat. [ABSTRACT FROM AUTHOR]

Background: Tree regeneration is a key component of resilience because it promotes post-disturbance recovery of forests. Northwestern Patagonia from Argentina is occupied by Nothofagus alpina (Na), N. obliqua (No), and N. dombeyi (Nd) forests that grow along an intense precipitation gradient, managed throughout shelterwood silvicultural system by technicians of the Lanin Natural Reserve. The objective of this study was to evaluate the influence of seeding cuttings over the dynamics of Nothofagus mixed forests across landscape (precipitation gradient) based mainly on the composition and abundance of tree regeneration, permanent sampling plots and generalized linear mixed models. In particular, we analysed: (i) the structure of sexual and asexual regeneration during < 10, 10–20 and > 20 years after harvest (the dynamics of managed forests), and (ii) the structure of sexual regeneration in primary and managed forests after > 20 years of harvest (the effect of silviculture). Results: Nd was the most abundant species in the regeneration of managed forests during all periods in both sites despite its lower contribution to the adult cohort. During the 10–20 years period after harvest, the humid site exhibited higher regeneration density than the mesic site (120,000 and 6000 ind ha−1, respectively), and it decreased afterwards. The number of established regeneration (> 2 m height) was lower for Na in the mesic site and for No in the humid site (0 and 57 ind ha−1, respectively). However, in comparison to No, Na showed a higher number of sprouted stumps and sprouts per stump, and a higher sprout height in the mesic site. No exhibited higher sprout mortality in the humid site. Finally, the regeneration of primary forests showed lower density and height, and a more balanced composition than that of managed forests. Conclusions: The silvicultural effects on the mixed forest regeneration dynamics was strongly influenced by the condition of sites. Therefore, management prescriptions should be adjusted in order to consider the environmental variation occurring through the entire landscape. An adaptive management that considers the pattern and process of sexual and asexual regeneration and disturbance will contribute to promote a greater resilience of mixed forest ecosystems. [ABSTRACT FROM AUTHOR]

The middle zone of the Hyrcanian forest located in the Mazandaran—Iran has experienced several silvicultural systems in which wood harvesting using clear-cutting, shelterwood, single-selection methods, and reforestation implemented under even- or uneven-aged stands for the past four decades. Studies on their implications led us to apply innovatively nuclear techniques to estimate their impacts on soil redistribution. The reasonability of the 137Cs inventory (4335 Bq m−2) and soil organic carbon (SOC) stock (220 t ha−1) in the representative reference site was approved. However, results imply losing ≈ 110 tones of SOC per hectare through silvicultural systems since their initiation. In addition to SOC, the annual soil erosion rate due to cultivated uneven-aged trees was 28.16 tonnes per hectare (1.5 mm yr−1); in contrast, the soil erosion (per hectare) through the cultivation of even-aged trees has been annually 14.5 tones (0.095 mm yr−1). The ability of nuclear techniques to reveal a higher soil-conserving efficiency (≈ 50%) of even-aged stands compared to uneven-aged trees and up to 15% restoration of SOC stock was the desired achievement. Practical strategies and approaches for silvicultural systems to restore degraded forest watersheds were tangible outcomes of the research. Forest management plans will be more effective for soil conservation using the introduced preferential cultivation methods. Scholars should consider the FRN's properties and the IAEA standards for such studies. [ABSTRACT FROM AUTHOR]

Assessing the financial, energy and emission levels associated with alternative harvesting prescriptions, techniques, and technologies is crucial to sustainable forest management. This study aims at developing an overall predictive system able to estimate productivity, fuel consumption and emissions for a set of different forest harvesting technologies as a function of stand characteristics, site conditions and silvicultural prescriptions. The system consists of two separate group of models, one for felling and processing, and the other for extraction. In the first model, six quantitative (DBH, tree volume, harvest, engine power, purchase price of the machine) and five qualitative independent variables (forest species, management, treatment, operation, type of machine, type of fuel) were considered. In the second model, four qualitative and six quantitative independent variables were applied. Both models have been trained on a large database of real field data using linear and nonlinear approaches based on artificial intelligence. The dataset was randomly separated into two subsets, one using for training the models and the other for validating them. The models reliably predicted fuel consumption (r = 0.84–0.95), energy emission and cost (r = 0.88–0.98), per hour and per hectare, and they were successfully validated. Despite being estimated from a heterogeneous input dataset, constituted by quantitative and qualitative variables, both models proved to be efficient, robust and generally representative. The input variables are intuitive and suitable for practical use by both entrepreneurs and policy makers at the institutional level. [ABSTRACT FROM AUTHOR]

In the middle of the last century, a system of field protective forest belts was created in North-Eastern Bulgaria to protect agricultural lands and increase yields from cereals and other agricultural crops. Forest roads were also built, ensuring the implementation of silvicultural activities in field protective forest belts. It was found what part of the forest roads in the region of Dobrudzha are stabilized with crushed stone, and the rest are dirt roads without stabilization. It has been established what part of the forest roads in the region are stabilized with crushed stone, and what part are dirt roads without stabilization. [ABSTRACT FROM AUTHOR]

The Notre-Dame de Paris (NDP) wooden oak frame is one of the greatest masterpieces of Gothic carpentry in France. It was constructed between 12th and 13th centuries, at a time of profound environmental and societal changes – climate optimum, strong demographic and economic growth – which created significant pressure on available forest resources, one of the key economic drivers of medieval societies. The project of the Notre-Dame oak wood frame study proposes four lines of research. The first three objectives aim to address society's adaptive response to the availability of wood resources during the High Middle Ages between the 11th and 13th c. The first objective is to study the timber and destroyed framework from an archaeological, mechanical and architectural point of view, in order to characterize the construction methods of the wooden frame and to identify the potential technical adaptations of the medieval society. The second purpose consists of characterizing the forest stands exploited, their management, and the possible silvicultural systems used for the production of adequate timber. The third purpose is to define the climatic and the socio-economical context of Paris and Ile-de-France via an unprecedented reconstruction of summer temperature and moisture from NDP woods, combined with textual sources. For the fourth objective, investigations on the hydro-mechanical properties of oak beams are undertaken to better understand the choice and use of oak beams in Middle Age for the NDP frame and to have the opportunities for innovations in wood uses in the context of European standard for timber buildings. [ABSTRACT FROM AUTHOR]

The aim of this paper was to assess the influence of the silvicultural system (clear-cut and shelterwood), species composition of forest stands, in relation to the fluctuation of raw wood prices, on the economic results of forest management. Model analyses were performed on the example of the conditions of the CZU Forests, specifically for the third forest vegetation zone, SLT 3K. The input to the model evaluation was: data on the growth and production of the investigated tree species in the given site conditions from growth tables, the costs of forestry measures were derived from standards, the assortment was carried out on the basis of assortment tables, the prices of assortments of raw wood were taken from the data of the Czech Statistical Office for 2015 and 2019. The synthetic result of the model evaluations was the gross profit of forest production per hectare and year. The results of the analysis prove the economic advantage and greater stability of the shelterwood silvicultural system, especially with regard to lower silvicultural costs, higher volume of timber production and mutual compensation of the decrease and increase in the prices of raw wood of the evaluated tree species. [ABSTRACT FROM AUTHOR]

Forest management modifies tree cover, directly influencing various ecosystem services, such as water regulation. Evapotranspiration, water interception, surface runoff, stemflow, and throughfall are among those processes that depend on tree cover. The objective of this study was to evaluate the changes in water yield, defined as the difference between precipitation and evapotranspiration, after the application of silvicultural treatments in a temperate forest ecosystem in northern Mexico. Fifteen experimental plots were established in which the following treatments were applied: intensive management (clearcutting), semi-intensive management (selection, tree cutting of 59–61% of basal area), conservative management (selection, tree cutting of 29–31% of basal area), and no treatment (control group). Incident precipitation, throughfall, stemflow, net precipitation, interception, and surface runoff were analyzed. Results show that conservative management treatments increase water yield between 2 to 3.6 mm per m-2 ha-1 of tree basal area removed. Water flow distribution, in relation to the incident precipitation, ranged from 72.3 to 91.8% for throughfall, 0.2 to 0.4% for stemflow, 72.7 to 91.8% for net precipitation, 8.19 to 27.42% for interception or evaporation, and 0.54 to 1.93% for surface runoff. The conservative management treatment was the most viable alternative for increasing water yield without compromising timber harvesting and loss of soil due to hydric erosion. [ABSTRACT FROM AUTHOR]

Pruning is a necessary part of tree management both in silvicultural systems and in urban forestry. For the wood industry's production of high-quality timber, as well as for the urban forest's risk reduction and ecosystem services enhancements, it is essential that the pruning is accurately implemented. This study aimed to determine the effect of pruning season on discoloration amount and occlusion rate in four broadleaved tree species. In 2014, 84 trees were pruned in January, May and September. Six years later, the 252 samples from the three pruning points per tree were collected and analysed. 'Common oak (Quercus robur L.)' and 'small-leaved lime (Tilia cordata Mill.)' showed least discoloration when pruned in January, 'wild cherry (Prunus avium L.)' showed least discoloration when pruned in September and 'Norway maple (Acer platanoides L.)' did not show any significant differences. All species occluded fastest when pruned in January, but at different rates. Common oak occluded 84 per cent of the samples, Norway maple 42 per cent, small-leaved lime 32 per cent and wild cherry 13 per cent. In summary, the pruning month affected discoloration amounts and occlusion rates of the tested tree species in varied ways. Our research suggests an important knowledge gap regarding optimal species-specific pruning times and underlying reasons for different reactions to pruning. [ABSTRACT FROM AUTHOR]

Anticipating consequences of disturbance interactions on ecosystem structure and function is a critical management priority as disturbance activity increases with warming climate. Across the Northern Hemisphere, extensive tree mortality from recent bark beetle outbreaks raises concerns about potential fire behavior and post-fire forest function. Silvicultural treatments (that is, partial or complete cutting of forest stands) may reduce outbreak severity and subsequent fuel loads, but longevity of pre-outbreak treatment effects on outbreak severity and post-outbreak fuel profiles remains underexplored. Further, treatments may present tradeoffs for other management objectives focused on ecosystem services (for example, carbon storage). We measured structure in old-growth subalpine forests following a recent (early 2000s) severe mountain pine beetle (MPB; Dendroctonus ponderosae) outbreak to examine effects of historical (1940s) cutting intensity on gray stage (~10 years after peak of outbreak) post-outbreak (1) fuel profiles and (2) aboveground biomass carbon. Compared to control (uncut) stands, historically cut stands subjected to the same MPB outbreak had approximately half the post-outbreak surface fuel loads, about 2–3x greater live canopy fuel loads, and greater within-stand spatial heterogeneity of dead canopy cover and available canopy fuel load. Post-outbreak total aboveground biomass carbon was similar across all stands, though historically cut stands had about 2x greater carbon in live biomass compared to uncut stands. These findings suggest tradeoffs with altered post-outbreak potential fire behavior and carbon storage in cut stands. Additional implications of historical silvicultural treatments for wildlife habitat, firefighting operations, and long-term carbon trajectories highlight temporal legacies of management on directing forest response to interacting disturbances. [ABSTRACT FROM AUTHOR]

Iran is located in a dry climate zone, and climate change has substantially reduced its precipitation and water resources. Reusing wastewaters from urban communities can meet some requirements for irrigation and fertilization of tree plantations in arid environments, leading to sustainable wastewater recycling, enhanced biomass production, and reduced land degradation. The objective of this study was to test the growth, biomass, nutrition, and heavy-metal accumulation of poplars [Populus nigra L. "62/154," P. alba L. "20/45," P. euramericana (Dode) Guinier "92/40"], and willow (Salix excelsa S.G. Gmel) in a pot experiment at four and eight months after planting when grown in soils irrigated with tap water (SITW) and wastewater (SIWW). After four months, SIWW treatment had no significant effect on growth, biomass, nor absorption of macronutrients. After eight months, SIWW treatment of poplars and willow significantly (p = 0.000) increased: (1) height, (2) leaf area, (3) root, stem, leaf, and total biomass, and (5) phytoextraction and phytoaccumulation of macro-/micro-nutrients and heavy metals in tree tissues, over trees receiving the SITW treatment. There were significant differences in growth, biomass, and accumulation of micronutrients and heavy metals in poplar versus willow tissues, with the highest biomass production and tissue-specific content of heavy metals in P. nigra trees, and the greatest total concentrations of heavy metals in P. alba and S. excelsa trees. In contrast, uptake of Fe, Cu, Ni, Cr and Pb were similar between poplar and willow, and phytoaccumulation of these elements was primarily in the roots. Leaf concentrations were highest for Zn and Mn. While P. nigra outperformed all other species overall, tolerance index (TI; defined as the tolerance to the heavy metals as calculated by the ratio of the biomass of SIWW trees relative to SITW trees) values exceeding 100% for all one-year-old poplar and willow trees demonstrated that they can be considered for planting in soil affected by urban wastewaters with similar contaminant profiles as in the current study. Since the species would differ in their growth, biomass, and phytoremediation responses to the nutrient and heavy metal concentrations of the wastewater over time, this research is important for the development of silvicultural prescriptions of these fast-growing trees that support effective wastewater reuse strategies throughout heterogeneous landscapes and across variable human community resources and needs. [ABSTRACT FROM AUTHOR]

Managing a complex social-ecological system requires data about the many social and ecological variables characterizing it and about their interactions. While the selection of research topics has its own, mostly unpredictable dynamics and contingencies, there has been a recent surge of interest regarding the involvement of non-academic stakeholders in suggesting research topics and identifying perceived knowledge gaps regarding the management of complex social-ecological systems. Decision-makers will invariably be confronted with limitations regarding resources to be allocated to the study of various systems components, and regarding the processing capacity of scientists and other stakeholders alike. Matang forest is one of the longest-managed mangroves in the world and provides a widely cited example of silvicultural management for charcoal and pole production, while providing a range of other ecosystem services. We applied the nominal group technique (NGT) to identify research priorities for Matang, as it provides a systematic and participatory approach to identify collective priorities while also reducing bias. The method consists of two rounds, during which participants were asked to reflect first individually, and then collectively, about key characteristics of mangrove management and about research priorities in Matang. The results were compared to the recommendations of the scientific literature. NGT provides a rapid, robust and systematic approach to identify research priorities for mangrove management and can hence be a timely method to support decision-makers across South-East Asia in guiding resource allocation toward research needs in times of increasing mangrove degradation. This is the first time that the application of NGT has been documented in a mangrove context. Moreover, NGT is not yet being used frequently in natural resources management, hence in documenting our NGT application, we aim to contribute to the development of a the NGT body of knowledge beyond mere mangrove forest settings. Rapid methods (such as NGT) to identify pressing research priorities are needed to guide resource allocation and investment of time and scientific capacity based on a systematic and pluralistic assessment. [ABSTRACT FROM AUTHOR]

We implemented a fire modeling approach to evaluate the effectiveness of silvicultural treatments in reducing potential losses to the Hyrcanian temperate forests of northern Iran, in the Siahkal National Forest (57,110 ha). We compared the effectiveness of selection cutting, low thinning, crown thinning, and clear-cutting treatments implemented during the last ten years (n = 241, 9500-ha) on simulated stand-scale and landscape-scale fire behavior. First, we built a set of fuel models for the different treatment prescriptions. We then modeled 10,000 fires at the 30-m resolution, assuming low, moderate, high, very high, and extreme weather scenarios and human-caused ignition patterns. Finally, we implemented a One-way ANOVA test to analyze stand-level and landscape-scale modeling output differences between treated and untreated conditions. The results showed a significant reduction of stand-level fire hazard, where the average conditional flame length and crown fire probability was reduced by about 12 and 22%, respectively. The conifer plantation patches presented the most significant reduction in the crown fire probability (>35%). On the other hand, we found a minor increase in the overall burn probability and fire size at the landscape scale. Stochastic fire modeling captured the complex interactions among terrain, vegetation, ignition locations, and weather conditions in the study area. Our findings highlight fuel treatment efficacy for moderating potential fire risk and restoring fuel profiles in fire-sensitive temperate forests of northern Iran, where the growing persistent droughts and fuel buildup can lead to extreme fires in the near future. [ABSTRACT FROM AUTHOR]

We investigated the morphophysiological mechanisms indicative of resource uses behind net primary production in seedlings of three valuable forest species of socio-economic value in the Amazon:mahogany (Swietenia macrophylla), Brazil nut (Bertholletia excelsa) and Laurel (Cordia alliodora). The hypotheses tested were: (i) the three species will grow better under mild to high light but with different magnitudes of response; and (ii) the three species will show different mechanisms to reach a better growth under mild to high light We measured biomass production and a set of morphophysiological leaf traits and calculated the relative growth rates (diameter and height) of seedlings subjected to low(0.9), moderate (11.3) and high (45.0 mol m-2 day-1) irradiance for 80 days. For all species, biomass and growth increase with irradiance and the magnitude of the effect were species-dependent. The changes in total biomass by irradiance varied 1.5-fold (B. excelsa) and twofold (S. macrophylla). Light-induced changes in biomass partitioning and morphophysiological traits varied among species. S. macrophylla and C. alliodora significantly increased root/aboveground mass ratio (R/A) under high irradiance. Gas exchange increased with irradiance for C. alliodora and B. excelsa. The non-structural carbohydrates of C. alliodora and S. macrophylla were greater in high (total soluble sugars) and moderate (starch) light environments. The traits associated with total biomass were starch, stomatal conductance and transpiration for B. excelsa; leaf area ratio, leaf area root mass ratio, total soluble sugars and starch for C. alliodora; and RIA, leaf area ratio, and leaf area root mass ratio for S. macrophylla. The species obtained a high total biomass under mild to high irradiance but following different morphophysiological mechanisms. We discussed the potential to use these mechanisms in silvicultural systems designed to supply the plants with intermediate to high levels of light, for example enrichment planting in secondary forests or reforestation on degraded areas. [ABSTRACT FROM AUTHOR]

This study investigated the initial growth, survival rate, and biomass content of Khaya senegalensis in a pure plantation system and under an agroforestry system (AFS) with banana and corn. The experiment was carried out in Northeast Brazil and measurements were made when trees were 30 months old. Spacing was 3 × 2 m and 3.5 × 3.5 m in pure plantation and in AFS, respectively. Banana and corn amounted to roughly 816 and 28.000 plants per ha for pure and AFS, respectively. The survival rate (99.7 × 96.1%) and wood density (595 × 551 kg dm−3) showed no difference between both systems. Individual growth was similar between both systems (0.0068 m3 tree−1). However, at the stand scale, yield was higher in pure plantation with a mean annual increase of 3.07 m3 ha−1 year−1, which means 129% higher than in AFS (1.34 m3 ha−1 year−1). Nevertheless, AFS added 20 and 8 t ha−1 of banana and green corn. Aboveground biomass accumulated at 30 months was 144% higher in the pure plantation (7.11 × 2.92 t ha−1), mainly leaf biomass, which was 228% higher in relation to AFS. In long rotation silvicultural systems like those used for African mahogany, only 100–400 trees per hectare will remain until the end of the rotation. As there was no difference in individual growth between the two systems, the AFS could be a very interesting alternative to mitigate establishment costs and optimizing land use with the production of agricultural crops specially to small farmers. [ABSTRACT FROM AUTHOR]

(1) Background: In Japan, single-tree selection-cutting silviculture with hiba (Thujopsis dolabrata var. hondai) is a traditional silvicultural system and is well documented. We evaluated an experimental forest regarding past structural dynamics and future development while comparing it to the German multilayer coniferous "Plenterwald/plenter forest". (2) Methods: Classical growth and yield data were recorded since 1995 from two hiba-mixed species plots, one managed since Matsukawa's (the founder) times in 1931 and the other unmanaged since 40–50 years before 1931. (3) Results: Clear structural differences appeared, with the managed plot having a reverse J-shaped DBH and tree height distribution curve, and a higher percentage of hiba, also typical for German plenter forests' intensely multi-storied structure. The unmanaged plot was composed of trees with large stem diameters, even though they were more evenly distributed, together with less admixed species. In both plots, the growing stock increased in the past. While the managed plot's growing stock in 2019 was 561 m3 ha−1, the unmanaged plot reached 982 m3 ha−1 with large portions accumulated in DBH classes >60 cm. (4) Conclusions: When compared to today's clearcutting system in Japan, selection silviculture shows advantages and may thus serve as a valuable inspiration for silviculture in Japan as it was with plenter forestry for Germany. [ABSTRACT FROM AUTHOR]

Silvicultural thinning can lead to rapid microclimatic changes for residual trees. Despite the benefits of decreased competition, thinning may induce "thinning shock"—temporary negative physiological responses as trees acclimate to new conditions. We examined the impact of thinning on the microclimate and physiology of residual, previously shaded red spruce (Picea rubens Sarg.) trees relative to non-thinned controls. Both daily maximum temperature and vapor pressure deficit increased post thinning, with larger increases observed on hotter and drier days. In response to these environmental changes, we found clear evidence of physiological declines. At 1.7 weeks post thinning, we found a 0.59 MPa reduction in average midday water potential relative to control trees, which lasted for an additional 1.4 weeks. Thus, the trees in the thinning treatment were at or beyond published estimates of needle turgor loss. Thinning decreased the photosynthetic efficiency of current-year needles by 3.8% after 2 weeks, and it declined by 1.3% per week for the remainder of the growing season. These results suggest that thinning shock occurs in red spruce, a shade-adapted, climate-sensitive species. Thinning shock may contribute to the lagged growth responses commonly observed post thinning, and these effects may be more extreme in novel future climates. [ABSTRACT FROM AUTHOR]

Cultural ecosystem services offer a range of benefits for human well-being, but from an identity perspective. These benefits include aesthetic experiences, knowledge and skills, spirituality, involvement in nature conservation, which means that, indirectly, cultural services ensure the preservation of all forms of life. The concept of cultural ecosystem services has become increasingly important in recent years as it helps to understand the socio-cultural value of forests and to balance stakeholder interests in forest management. In Romania, ecosystem services are recognised through the protection and production functions attributed to forests. Fortunately, the Romanian forestry system integrates many ecosystem services in the process of developing forest management, the first correlation between the specific functional categories of each stand type and the proposed silvicultural measures. Moreover, the mixed forestry policy instruments for forest ecosystem services refer to the necessary documents on the harmonisation of forestry planning with the management plan of protected natural areas and with the complementary ones offered by the FSC certification system. Cultural ecosystem services face several challenges, one of which is the lack of coherent concepts that hinder the assessment and integration of forest ecosystem services into landscape architecture design. The results of the analysis show that forests with a cultural role identified through the certification process generally refer to forests near cultural and/or heritage buildings (such as churches and monasteries) or forests offering important aesthetic and/or recreational values. Clearly, forest management certification contributes, with a simple methodological approach, to the identification of forests with a cultural role, especially in situations where forest management plans do not give them priority due to the limitations of functional zoning criteria. More than 40% of the cultural forests analysed have a recreational and ecotourism role, followed by those with spiritual or religious value with 18% of the total area of cultural forests analysed. Although seven types of cultural ecosystem services have been identified through this study, the cultural diversity component is impossible to differentiate at the national level because cultural diversity implies the existence of indigenous populations. Instead, the study can be expanded on a larger scale to identify more forests with inspirational or aesthetic value, both of which are valued at the landscape level. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) is of most importance for the development of all ecosystems, specifically carbon forest stock, as it is affected by climate, tree species and forest management. The aim of this study is to determine SOC changes in an Umbrisol under forest management in a temperate forest in Mexico. Three silvicultural forest stands were analyzed (Clear cutting, Seed-trees and Selection) and compared with a Post-fire area and a Reference stand. At each stand, 4 composite soil samples were collected at two depths (0–20 and 20–40 cm) to determine SOC; the values obtained from these samples were then used as inputs for the RothC 26 model. The ANOVA indicated differences in the SOC between stands and depths. Seed-trees showed highest content of SOC (0–20 cm), with an increase of 63% with respect to Reference. At depth 20–40 cm, Clear cutting presented the highest SOC, with increase rates above 100% with respect to Reference. Differences in the SOC can be attributed to litter deposition from forest harvesting and fires. Forest management contributes to improving and increasing the capacity of Umbrisols as carbon reservoirs. The modeled scenarios for both depths showed that SOC reservoirs reach an equilibrium after 50–60 years. [ABSTRACT FROM AUTHOR]

The use and consumption of wood has always captured the attention of forest researchers, mainly from the point of view of forest management and the sustainable processing of raw materials. For this reason, the wood industry has not only been concerned with the maintenance of forests, but also with efficient processing. The objective was to identify, analyse and discuss the main elements that influence the efficient use of natural timber resources at a global, regional and local level, providing a historical and current perspective of the industrial forestry sector in Mexico. Historically, the wood industries worldwide have been concerned with applying intensive silvicultural treatments in native and artificial forest stands, in search of satisfying the demand of a growing market. In this context, industries evolved as processes needed to be more efficient. Therefore, efforts were made to reduce and take advantage of forest residues, at the same time various historical events generated additional needs. At present, the integration of silviculture and forest transformation allow to increase and improve the quality of the products generated. Through the application of intensive silvicultural treatments, products of a single species are obtained. However, it is possible to direct production to a specific market as the forest mass develops. For its part, selective treatments in uneven-aged forests maintain a constant production of diverse products for different specialized markets. In Mexico, it is imperative to analyse and generate innovative or competitive products derived from wood to improve the efficiency of forest harvesting. [ABSTRACT FROM AUTHOR]

Key message: The modelling approach presented and tested in the present study relates local management decisions with efficiency indicators of the whole wood fuel chain, based on decisions ranging from silviculture to transport to customer. Energy and worktime efficiencies were better under large-scale energy production associated with high wood fuel demand, whereas nutrient efficiency was better under small-scale production associated with a moderate demand. Local management decisions all along the wood fuel chain highly influenced efficiency indicators, and thus its relevance for energy-transition policies. Context: Bioenergy from wood can contribute to reach the goals of energy-transition policies. Use of wood as fuel should focus on low-quality wood, e.g. by-products from timber production, which production and supply is related to various management decisions. Reaching the policy objectives efficiently remains an issue. Aims: The aims are (1) to develop a modelling approach that links local management decisions with indicators of the whole wood fuel production and supply chain and (2) to test the model in a case study. The study should further provide first insights on how indicators of energy, nutrient and worktime efficiency vary according to wood fuel chain characteristics and the related management decisions. Methods: The model depicts the flow of wood (biomass, nutrients, moisture content, heating value) from the forest stand to the heating plant for each silvicultural intervention simulated with a growth and yield model. It further quantifies the energy and worktime spent on different wood fuel chain tasks (e.g. felling, forwarding) set by the user. We defined four scenarios according to the scale of energy production (large vs. small) and the demand for wood fuel (high vs. moderate). Results: The case study revealed that the model outputs were plausible. Energy efficiency largely varied depending on the type of silvicultural intervention. Large-scale production associated with high demand was most favourable for energy and worktime efficiencies. In contrast, nutrient efficiency was best for small-scale production associated with moderate demand. Conclusions: Local management decisions all along the wood fuel chain highly influenced efficiency indicators, and thus its relevance for energy-transition policies. Our model may contribute to strategic decision making in different forestry and energy production contexts. [ABSTRACT FROM AUTHOR]

The renewal and sustainability of the forest stands are attained through regeneration. There are three basic methods to regenerate high forest stands: natural regeneration, direct seeding, and planting. This study reviews the factors affecting regeneration, the three methods of regeneration and the effect of stand structure on regeneration. Overall, regeneration success can be quite variable due to edaphic and climatic conditions, seed losses and/or seedling mortality. The silvicultural system is relevant to the choice of the regeneration method. Natural regeneration is used in selection and irregular shelterwood systems whereas direct seeding and planting are used in uniform shelterwood and clear-cut systems. In the former, stand stocking management is primordial to regeneration success while for the latter are species selection, seed predators and spontaneous vegetation control.

Cordulegaster heros is included in the EN category on the IUCN Red List for the territory of the Czech Republic, where it inhabits an area of approximately 100 km2. All of the localities are located in the forest complex in Chřiby hills, and all of the forests fall into the category of management forests. Most of the forest stands have a high and very high degree of naturalness; they are natural forest stands. The predominant management units are Nutrient sites in middle elevations (78.2% of the area) and Oligotrophic sites in middle elevations (2.1% of the area), with stand types of Fagus sylvatica representing 92.5% of the area, and forest stand types of Quercus sp. representing 5.7% of the area. The wider alluvia in forest streams are classified as being in management unit alder and ash sites on waterlogged and floodplain soils (1.1%), with the forest stand type of Alnus glutinosa. The forest stands are restored by regeneration under shelterwood (97.8% of the area). The waterlogged alluvia, if a separate management unit is established for them, are restored by a regeneration by strip method. Realistically, seven factors were recorded in C. heros habitats, but they mostly have only point effects. Within forestry management, the factors of logging directly in the habitats and the subsequent transport of harvested timber in the habitat were recorded. The most intrusive effects were found on tractor logging roads, where fine soil washes into the stream and causes prolonged turbidity. Of the water management structures in the study area, logging roads with bridges and culverts are constructed, stream banks are reinforced with longitudinal walls at points, and stone steps in the channels are constructed only sporadically. The current forest management system can be described as a nature-friendly system, and therefore, it fully ensures the conditions for the survival of the C. heros population in the Czech Republic. [ABSTRACT FROM AUTHOR]

Variable retention harvest (VRH) is a silvicultural approach that retains differing proportions and patterns of canopy trees across a harvested area to emulate natural disturbance effects on stand structure and enhance the resilience of the regenerating stand to abiotic and biotic stresses. Four VRH treatments were applied to an 83‐year‐old red pine (Pinus resinosa Ait.) plantation forest in the Mixedwood Plains Ecozone of Canada that included 55% aggregate retention (55A), 55% dispersed retention (55D), 33% aggregate retention (33A), 33% dispersed retention (33D) and an unharvested control (CN). In the sixth growing season after harvest, tree stem sap flow and eddy covariance flux measurements were used to examine the impacts of VRH on the dominant components of total stand evapotranspiration (ET), i.e., canopy transpiration (TC) and water flux from the understory vegetation and soil (ETU) as well as understory and canopy water use efficiency (WUE). A positive relationship was found between harvest intensity and the growth of understory vegetation and ETU. The contribution of ETU to ET was higher in the dispersed compared to the aggregate VRH treatments. Canopy transpiration contributed 83% of ET in the CN plot and 58%, 55%, 30% and 23% in the 55D, 55A, 33A and 33D treatments, respectively. Overall, VRH treatments resulted in increased canopy WUE but little comparative effect on understory WUE. Our results suggest that the dispersed retention pattern led to higher ET and productivity than the aggregate pattern of the same retention level. Where carbon sequestration and climate change mitigation is the primary management objective, higher retention levels such as 55D might be used to favour stand level carbon storage while accepting slower rates of understory development. Our findings on the effects of VRH on productivity and WUE of the canopy and understory will help forest managers to better employ VRH as an option to meet multiple objectives and adapt forests to a warmer, more variable climate. [ABSTRACT FROM AUTHOR]

Comparing forest and harvested wood product carbon (C) stocks and accumulation among forest management treatments commonly applied in managed forests is needed to inform planning and policy decisions for C objectives. Therefore, pre- and post-harvest C stocks were quantified and C accumulation was projected over a 31-year period (to ∼2050) among forest management treatments that were applied on a subset (n = 3) of the Maine Adaptive Silviculture Network installations in northern Maine, USA. These installations included mature, second-growth forests composed of northern hardwood and hardwood-dominated mixedwood stands. Before treatments were initiated, average aboveground live tree C stocks ranged from 67.1 to 99.7 Mg ha−1. For the aboveground portions of live trees, dead wood and harvested wood products, the projected average annual net change in C (AAC) was 0.232 ± 1.164 Mg ha−1 year−1 (mean ± standard deviation). Models of projected AAC indicated that less biomass removal during harvests and greater representation of tree species with low tolerance of shade were associated with positive AAC values. The results emphasize the importance of leveraging multiple harvesting strategies to achieve C objectives, including consideration of forest reserves and using targeted yet operationally feasible silvicultural treatments that promote forest resilience relative to climate change. [ABSTRACT FROM AUTHOR]

Recent model projections and many research results across the world suggest that forests could be significant carbon sinks or sources in the future, contributing in a such a way to global warming mitigation. Conversion of coppice forest to high forest may play an important role towards this direction. This study deals with the estimation of biomass, carbon pool and accumulation rates in all IPCC biomass categories of a 77 year-old oak ecosystem, which has been subjected to conversion from coppice to high forest through repeated tending measures. The research includes a plethora of field tree measurements, destructive sampling of representative oak trees and a systematic sampling of dead wood (standing and fallen), litter and soil. Furthermore, for the estimation of above ground tree living biomass at the stand level, we developed and tested appropriate allometric biomass equations based on the relationships between various independent tree variables (morphological characteristics) and the different tree biomass compartments or leaf biomass. Data analysis shows that coppice conversion results in large accumulation of carbon in all ecosystem pools, with an average annual carbon rate accumulation of 1.97 Mg ha–1 in living above and below ground tree biomass and small amounts to dead wood and litter. The developed allometric equations indicate that above ground tree living biomass can be reliable and precisely predicted by the simple measurement of tree diameter. [ABSTRACT FROM AUTHOR]

Numerous forests in the eastern United States have been degraded due to past exploitative timber harvesting known as high grading. High graded forest stands may not improve without active rehabilitation and may require targeted silvicultural treatments. This study focuses on high graded mixed-oak (mixed- Quercus spp.) stands and aims to develop a model that can identify past high grading and to determine modifications that may improve forest management recommendations provided by the prominent decision support tool, SILVAH. We present a model that uses standard forest inventory measurements and does not require knowledge of preharvest stand conditions to predict with moderate to high accuracy whether a stand was high graded, which could be particularly useful for nonindustrial private forests. Results indicate that modifications to SILVAH may be necessary to improve its utility for prescribing silvicultural treatments in high graded stands. [ABSTRACT FROM AUTHOR]

Aim: Eucalypts have a widespread global distribution owing to their popularity for agroforestry and as environmental plantings. Despite an abundance of site‐specific evidence that eucalypts modify soils and soil processes, we lack a quantitative synthesis of their overall effects at the global scale. This limits our capacity to assess the likely impacts of future introductions in any given region of the world. Location: Global. Time period: 1986–2021. Major taxa studied: Eucalyptus, Angophora and Corymbia. Methods: We used a systematic search to derive a database of empirical data from 227 studies across 33 countries (neffect size = 2,806) and tested three predictions about the effects of eucalypts on soil properties and whether these effects varied with plantation age and soil depth. Results: Compared with (non‐eucalypt) native vegetation, eucalypts significantly reduced soil moisture, microbial abundance, nitrogen, cations and anions. Relative reductions in soil microbes and ions were stronger in older eucalypt plantations. A comparison of eucalypts with (non‐eucalypt) silvicultural and agropastoral systems revealed similar effects on most soil properties, although eucalypts tended to reduce potassium and enhance carbon to a greater extent than other managed systems. We found no consistent effects of eucalypts on soil pH. Main conclusions: Our study provides the first extensive global meta‐analysis of the effects of eucalypts on soil properties and processes and demonstrates that effects are highly dependent on the community with which they are compared (i.e., natural or managed). In general, our findings reinforce the widely held belief that eucalypts deplete soil nutrients and dominate water resources. Understanding how eucalypts affect soils allows us to assess their global suitability for agroforestry, soil rehabilitation and soil carbon enhancement, while considering the potential environmental costs. [ABSTRACT FROM AUTHOR]

Natural dynamics in forests play an important role in the lives of many species. In the landscape of managed forests, natural disturbances are reduced by management activities. This usually has a significant effect on insect diversity. The effect of small-scale natural dynamics of protected beech stands on the richness of saproxylic and non-saproxylic beetles was investigated. Sampling was carried out by using flight interception traps in the framework of comparing different developmental stages: optimum, disintegration, and growing up, each utilizing 10 samples. We recorded 290 species in total, of which 61% were saproxylic. The results showed that the highest species richness and thus abundance was in the disintegration stage. In each developmental stage, species variation was explained differently depending on the variable. Deadwood, microhabitats, and canopy openness were the main attributes in the later stages of development for saproxylic beetles. For non-saproxylics, variability was mostly explained by plant cover and canopy openness. Small-scale disturbances, undiminished by management activities, are an important element for biodiversity. They create more structurally diverse stands with a high supply of feeding and living habitats. In forestry practice, these conclusions can be imitated to the creation of small-scale silvicultural systems with active creation or retention of high stumps or lying logs. [ABSTRACT FROM AUTHOR]

In Europe, forest management has controlled forest dynamics to sustain commodity production over multiple centuries. Yet over‐regulation for growth and yield diminishes resilience to environmental stress as well as threatens biodiversity, leading to increasing forest susceptibility to an array of disturbances. These trends have stimulated interest in alternative management systems, including natural dynamics silviculture (NDS). NDS aims to emulate natural disturbance dynamics at stand and landscape scales through silvicultural manipulations of forest structure and landscape patterns. We adapted a "Comparability Index" (CI) to assess convergence/divergence between natural disturbances and forest management effects. We extended the original CI concept based on disturbance size and frequency by adding the residual structure of canopy trees after a disturbance as a third dimension. We populated the model by compiling data on natural disturbance dynamics and management from 13 countries in Europe, covering four major forest types (i.e., spruce, beech, oak, and pine‐dominated forests). We found that natural disturbances are highly variable in size, frequency, and residual structure, but European forest management fails to encompass this complexity. Silviculture in Europe is skewed toward even‐aged systems, used predominately (72.9% of management) across the countries assessed. The residual structure proved crucial in the comparison of natural disturbances and silvicultural systems. CI indicated the highest congruence between uneven‐aged silvicultural systems and key natural disturbance attributes. Even so, uneven‐aged practices emulated only a portion of the complexity associated with natural disturbance effects. The remaining silvicultural systems perform poorly in terms of retention compared to tree survivorship after natural disturbances. We suggest that NDS can enrich Europe's portfolio of management systems, for example where wood production is not the primary objective. NDS is especially relevant to forests managed for habitat quality, risk reduction, and a variety of ecosystem services. We suggest a holistic approach integrating NDS with more conventional practices. [ABSTRACT FROM AUTHOR]

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In last two decades a problem for determination of optimal rotation ages when considering not only wood production but carbon uptake has had big importance. The coppice stands in Bulgaria occupy approximately 47% of the forest area. The biggest part of it consists of species of genus Quercus which are managed by two silvicultural systems: traditional coppicing and conversion from coppice to high forest. The aim of this paper is to propose optimal rotation ages based on biological and technical maturity for two types of coppice oak stands: for compulsory conversion to high forest and for mixed coppice-seed management. Based on data obtained from forest management plans and temporary sample plots we propose different rotation ages from official regulations for main oak species and recommend some guidelines for forest management of coppice oak stands. [ABSTRACT FROM AUTHOR]

This work describes the development and analysis of a spatially explicit environmental model to estimate the current, ecological, condition class of a managed forest landscape in the southern United States. The model could be extendable to other similar temperate forest landscapes, yet is characterized as a problem-specific, hierarchical, binary process model given the explicit relationships it recognizes between the management of southern United States pine-dominated natural forests and historical ecological conditions. The model is theoretical, based on informed proposals of the landscape processes that influence the ecological condition, and their relationship to perceived ecological condition. The modeling effort is based on spatial data that describe the historical forest community classes, forest plan provisions, fire history, silvicultural treatments, and current vegetation conditions, and six potential ecological condition classes (ECC) are assigned to lands. A case study was provided involving a large national forest, and validation of the outcomes of the modelling effort suggested that the overall accuracy when predicting the exact ecological condition class was about 46%, while the overall accuracy ±1 class was about 81%. For large, heterogeneous forest areas, issues remain in estimating the input variables relatively accurately, particularly the pine basal area. [ABSTRACT FROM AUTHOR]

The increasing demand for plant‐derived bioenergy is projected to expand tree plantations with intensive silviculture and improved tree genetics. These silvicultural practices result in faster stand development and canopy closure, which may also influence the systems' water dynamics. Here, we studied the evapotranspiration (ET) of a young (5 years old) intensively managed loblolly pine (Pinus taeda) stand and investigated the components of ET to determine its contribution to overall water use. We also compared ET with plantations that received less intensive management to determine whether our stand used more water. We used the eddy covariance method to estimate ecosystem‐level total ET (ETEC), while plot‐level estimates of ET (ETP) were obtained via soil lysimeters, sap flow sensors, and throughfall collectors, enabling measurement of the components of ET. Soil evaporation (Es) was the largest component of ETP (36%) over the course of the study, while transpiration and canopy interception accounted for 27% and 22%, respectively. Es decreased with stand development, while transpiration and canopy interception increased. Leaf area index (LAI) and precipitation were the most significant factors controlling ET and its components. Compared to previous studies in different sites that have similar age but lower LAI, our stand had higher water use. This high water use in the early stages of stand development was primarily due to high Es before the canopy was fully developed. While there are potential sources of uncertainty when comparing ETEC and the component fluxes in ETP, results from the two methods were not significantly different. This study had the advantage of using multiple methods to understand and verify the component processes that contribute to ET. Therefore, we recommend that multiple measurement techniques be used in the long‐term observation of ET, and in particular for the evaluation of the impact that intensively managed forests have on water resources in the southeastern United States. [ABSTRACT FROM AUTHOR]

Excessive salts in degraded sodic soils aggravate the bio‐physicochemical properties of soils that need to be remediated and restored in a judicious way. The present study envisages smothering harmful effects of sodic soils and maintaining soil fertility through need‐based silvipastoral systems. We report on a three‐times replicated field experiment with 13 treatments comprised of three agroforestry tree species Acacia nilotica, Casuarina equisetifolia, and Eucalyptus tereticornis planted during 2005 on highly sodic soil of pH 10.6 and exchangeable sodium percentage (ESP) of 89 in the Indo‐Gangetic Plains. Fodder grass species viz. Chloris gayana, Panicum maximum, and Pennisetum purpureum were planted under each of the 10‐year‐old tree species. The maximum biomass production of understory grasses was recorded from A nilotica + C. gayana silvipastoral system while the highest nutritive value in terms of N. P, K, and crude protein content (%) was recorded in A. nilotica + P. purpureum. A strong correlation between photosynthetically active radiation (PAR) and understory grasses was observed. Significantly higher tree growth and biomass yield were recorded under silvipastoral systems over silvicultural system. A significant reduction in soil bulk density and increase in soil porosity, infiltration rate, and water holding capacity (WHC) were recorded in silvipastoral systems over silviculture and control due to reduced sodicity, addition of leaf litter, increase in microbial activities due to tree and grassroots, better plant growth, and fine root decay. Reduction in soil pH, exchangeable sodium percent (ESP), and increase in soil organic carbon were more pronounced under silvipastoral systems over the silviculture. The highest reduction in these parameters was recorded under the A. nilotica + C. gayana silvipastoral system. Similarly, soil microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), microbial biomass phosphorus (MBP), and dehydrogenase activities were higher under silvipastoral systems over the silvicultural system The highest MBC was recorded in C. equisetifolia + C. gayana which was 302.8% higher than the control. However, highest MBN and dehydrogenase activities were recorded under A. nilotica + C. gayana silvipastoral system. Hence, on the basis of total biomass yield and improvement in soil bio‐physicochemical properties A. nilotica + C. gayana silvipastoral system could be a highly ameliorative and productive system for the restoration of degraded sodic soils. [ABSTRACT FROM AUTHOR]