National Forest Research Articles

Ethno-botanical study of medicinal plants in Kalesar, Haryana, India

The current study focuses on the identification and gathering of data from the rangers, guides, and locals of the Kalesar village and Kalesar National Forest in the Yamunanagar district of Haryana. The ethnomedicinal qualities of the plants that were growing there and were used by the locals to treat illnesses are the focus of this study. Nearly 100 distinct plant species were identified, of which 77 were confirmed to exhibit ethno-medicinal qualities. Species belonging to families of Compositae, Rutaceae, Moraceae, Apocynaceae, Rosaceae, etc. were identified. With the aid of locals and the literature that was readily available, the plants were identified. The components of the plants that the locals utilized most frequently were the leaves, roots, seeds, and fruits, and these plants have shown notable success in treating conditions like as skin disorders, dental issues, gastrointestinal issues, and more. Additionally, it has been observed that they have anti-bacterial, anti-inflammatory, and anti-microbial characteristics.

Integrated Fire Management and Closer to Nature Forest Management at the Landscape Scale as a Holistic Approach to Foster Forest Resilience to Wildfires

Integrated Fire Management and Closer to Nature Forest Management at the Landscape Scale as a Holistic Approach to Foster Forest Resilience to Wildfires

Pemanfaatan Data Raster Dalam Menentukan Perubahan Penutupan Lahan Sub Daerah Aliran Sungai (DAS) Biyonga Kabupaten Gorontalo

This study aims to analyze changes in land cover over a specific period, focusing on the influencing factors and their impacts on the Biyonga Sub-Watershed ecosystem. The method used in this research is a combination of descriptive research method with spatial analysis interpretation approach and field survey. The research findings indicate that spatial analysis of land cover in the Biyonga Sub-Watershed revealed nine land cover classes, such as forest, shrubland, settlements, and agriculture. Land use change patterns were evaluated by overlaying land cover maps from 1990 to 2020. Significant changes in land cover occurred between 1990 and 2000, where secondary dryland forest cover changed to shrubland covering an area of 2,299.98 hectares. For the period 2000-2011, it was found that there was a loss of primary forest cover totaling 2097.27 hectares, which transitioned into secondary dry land forest and shrubland. Other changes included paddy fields transitioning into settlements and dry land agriculture, and dry land agriculture transitioning into settlements. From 2011 to 2020, there was an increase in the area of secondary forest cover and transitions from shrubland and dry land agriculture to secondary forest as well as mixed dry land agriculture.

Habitat niches of bird species along a recovery gradient in the Chocó tropical forest

Conservation programs need improved tools to measure the recovery of animal diversity across restoration gradients. We used soundscapes and expert identifications of bird species to calculate niche position (i.e., mean of environmental conditions across all areas a species occupies) and niche breadth (i.e., the standard deviation of the species distribution) along a recovery gradient; from agriculture to early (up to 20 yrs) and late (up to 38 yrs) recovery, to old-growth forests. Our survey included 323 bird species and was conducted in 66 plots in the lowland Chocoan tropical rainforest in Ecuador where less than 11% of the forest remains intact, and large areas are currently undergoing regeneration post-abandonment. First, we validated our niche metrics by contrasting them against independent global categories of forest density dependency. We then explained the niche metrics of the bird species with different ecological traits, gathered from the literature, reflecting species-specific primary diet, morphology and distribution, and accounting for the phylogenetic relatedness of species. Finally, we explored the phylogenetic signal present in bird species’ ecological traits and recovery niche metrics. Niche position and breadth across the recovery gradient closely followed global categories of forest density dependency. However, our approach provided a more fine-scaled sorting of bird species in forest plots categorized as late recovery and old-growth. Granivorous birds occupied niche positions in active cacao and pasture plots and were replaced by frugivorous birds in older regeneration plots. Along the recovery gradient, tail length and handwing index decreased with niche position, supporting previous observations that birds in old-growth forests are less mobile. Birds in old-growth forests had smaller global distribution ranges than birds in agricultural plots. Finally, the latitudinal distribution of birds in the study area averaged south of the equator, with birds in old-growth plots averaging latitudinal centroids in wet forests north of the equator, whereas birds in agriculture plots averaged latitudinal centroids further south of the country, towards the dry and open Tumbesian forest. Frugivores, invertivores and vertivores had broader niche breadths, but these decreased (marginally) with tail length. We suggest these recovery niche metrics as a potentially powerful tool for the rapid assessment of the recovery process, which might support conservation strategies such as biodiversity credits, compensation payments, and strategic land purchases. With the increasing availability of information-intensive models for bird species identification, such as deep learning artificial intelligence, our new niche metrics open the avenue for rapid assessment of tropical biodiversity and new conservation areas at larger scales.

Improving Otsu Method Parameters for Accurate and Efficient in LAI Measurement Using Fisheye Lens

The leaf area index (LAI) is an essential indicator for assessing vegetation growth and understanding the dynamics of forest ecosystems and is defined as the ratio of the total leaf surface area in the plant canopy to the corresponding surface area below it. LAI has applications for obtaining information on plant health, carbon cycling, and forest ecosystems. Due to their price and portability, mobile devices are becoming an alternative to measuring LAI. In this research, a new method for estimating LAI using a smart device with a fisheye lens (SFL) is proposed. The traditional Otsu method was enhanced to improve the accuracy and efficiency of foreground segmentation. The experimental samples were located in Gansu Ziwuling National Forest Park in Qingyang. In the accuracy parameter improvement experiment, the variance of the average LAI value obtained by using both zenith angle segmentation and azimuth angle segmentation methods was reduced by 50%. The results show that the segmentation of the front and back scenes of the new Otsu method is more accurate, and the obtained LAI values are more reliable. In the efficiency parameter improvement experiment, the time spent is reduced by 17.85% when the enhanced Otsu method is used to ensure that the data anomaly rate does not exceed 10%, which improves the integration of the algorithm into mobile devices and the efficiency of obtaining LAI. This study provides a fast and effective method for the near-ground measurement of forest vegetation productivity and provides help for the calculation of forest carbon sequestration efficiency, oxygen release rate, and forest water and soil conservation ability.

Metabolomics reveals changes in soil metabolic profiles during vegetation succession in karst area.

Soil metabolites are critical in regulating the dynamics of ecosystem structure and function, particularly in fragile karst ecosystems. Clarification of response of soil metabolism to vegetation succession in karst areas will contribute to the overall understanding and management of karst soils. Here, we investigated the metabolite characteristics of karst soils with different vegetation stages (grassland, brushwood, secondary forest and primary forest) based on untargeted metabolomics. We confirmed that the abundance and composition of soil metabolites altered with vegetation succession. Of the 403 metabolites we found, 157 had significantly varied expression levels across vegetation soils, including mainly lipids and lipid-like molecules, phenylpropanoids and polyketides, organic acids and derivatives. Certain soil metabolites, such as maltotetraose and bifurcose, were sensitive to vegetation succession, increasing significantly from grassland to brushwood and then decreasing dramatically in secondary and primary forests, making them possible indicators of karst vegetation succession. In addition, soil metabolic pathways, such as galactose metabolism and biosynthesis of unsaturated fatty acids, also changed with vegetation succession. This study characterized the soil metabolic profile in different vegetation stages during karst secondary succession, which would provide new insights for the management of karst soils.

Exploring Genetic Diversity and Variability of Tamarind (Tamarindus indica L.): A Comprehensive Study in the Bilaspur Region of Chhattisgarh, India

The genetic diversity and variability of Tamarindus indica L., a valuable multipurpose tree species, was investigated through a comprehensive study conducted in the Bilaspur region. This research aimed to assess the morphological variations and growth responses of T. indica under contrasting environments, specifically agroforestry and natural forest systems. The study employed a rigorous scientific approach, encompassing field surveys, statistical analyses, and morphological assessments. The results indicated pronounced morphological differences between T. indica trees in the agroforestry and natural forest systems. T. indica trees in the natural forest exhibited significantly greater average height and diameter at the breast height (DBH) compared to those in agroforestry settings, highlighting the influence of the environment on growth parameters. Here, the crown diameter displayed homogeneity across both environments, suggesting a potential level of adaptability in this trait. The findings show the importance of considering environmental conditions when assessing the growth and development of T. indica, providing valuable insights for both scientific research and practical applications in agroforestry and conservation efforts.

Effects of Ganoderma lucidum cultivation in forests on soil organic carbon pool and microbial community physiological profiles

Non-timber forest products increase forests resource utilization efficiency and promote rural areas economic development. Ganoderma lucidum (Curtis) P. Karst. (Reishi) is a mushroom having great potential being cultivated as NFTPs. However, there is still a lack of effects about cultivating Reishi in forests on soil organic carbon (C) pool and microbial community, which are important for designing sustainable cultivating strategies. Therefore, this study sampled and analyzed soil from forests cultivated Reishi at 2, 4, and 6 years (LZ2, LZ4, and LZ6, respectively), and in reference natural evergreen broad-leaved forest (CK). Our results manifested that, compared with CK, LZ2 slightly increased total organic carbon (TOC), and significantly increased microbial biomass carbon (MBC) and water-soluble organic carbon (WSOC) content by 29.99% and 28.67%, respectively ( P < 0.05). Besides, compared with CK, LZ2 significantly increased the ratio of MBC/TOC and WSOC/TOC by 37.50% and 35.00%, respectively ( P < 0.05). In contrast, these parameters decreased in LZ4 and LZ6 slightly, compared with CK. Consequently, LZ2 had the highest average well-color development values and microbial functional diversity indexes, while these parameters declined in LZ4 and LZ6, compared with CK. As a result, microbial community functional structure in LZ2 was different from that in LZ4, and LZ6, while that in LZ4 and LZ6 showed similarity, according to the principal component analysis and PERMANOVA test.

Construction of Remote Sensing Quantitative Model for Biomass of Deciduous Broad-Leaved Forest in Mazongling Nature Reserve Based on Machine Learning

As an important forest type, deciduous broad-leaved forest is crucial for estimating forest carbon sequestration capacity and evaluating forest carbon balance. This study focuses on the natural deciduous broad-leaved forest of Mazongling Nature Reserve in Jinzhai County of China. WorldView-2 images were selected as data source. 36 candidate factors including vegetation indices, texture features, and topographic factors were used for modelling. Three machine learning algorithms (i.e., random forest, k-nearest neighbor, and artificial neural network) were used to establish the optimal quantitative retrieval model for natural deciduous broad-leaved biomass. Results showed that the ANN model was the best predictor with R2 = 0.69 and RMSE = 31.53 (Mg·ha−1). Combining the ANN model with the complete spatial coverage of remote sensing data, we developed a distribution map of natural deciduous broad-leaved biomass in the Mazongling forest farm. The estimated average biomass of the study area was 90.34 ± 47.96 Mg·ha−1. In addition, the influence of light saturation on model accuracy is also discussed. This study confirms that remote sensing data in temporal and spatial space can improve the model estimation accuracy.

Land use intensity is a major driver of soil microbial and carbon cycling across an agricultural landscape

Soil carbon (C) storage is a critical ecosystem function that underpins human health and well-being. The acceleration of human-driven land use change, such as agricultural intensification, is a major driver of soil C loss globally. Developing sustainable land use practices that enhance agricultural productivity whilst protecting essential ecosystem functions such as soil C storage is vital. The soil microbiome has a critical role in regulating soil biogeochemical cycling processes, including soil C cycling. Examining the impacts of land use intensity on the soil microbiome enables us to assess the potential effects on long-term soil C stocks. Using metagenomic DNA sequencing and phospholipid fatty acid analysis, we investigated differences in the activity, diversity, and function of the soil microbiome associated with five contrasting land uses across an agricultural landscape. The land uses covered a gradient of disturbance intensities and included remnant native forest, regenerating native bush, exotic plantation forest, dryland pasture, and irrigated pasture. We identified pronounced differences in the soil microbiome associated with each land use, including the diversity and abundance of microbial C and nitrogen (N) cycling genes. Notably, intensive agricultural land uses had a significantly higher diversity and abundance of microbial C-degrading genes, whilst land uses of remnant native forest had the lowest diversity and abundance of microbial C-degrading genes. Our findings suggest that intensive agricultural land use may increase the functional potential of the soil microbiome to mineralize soil C, potentially resulting in a greater loss of soil C as respired CO2 into the atmosphere. This research may be used to support the development of sustainable management practices that promote the persistence of soil C across agricultural landscapes, such as the protection of remnant native forest fragments and greater incorporation of regenerating native vegetation.

Reassembly of ground-dwelling ant communities in reforestation plots in SW Costa Rica

AbstractDue to agriculture and logging, Costa Rica has lost many primary forests, making reforestation an important task. To judge the progress of reforestation, it is important to follow the reassembly of organismal communities within restored habitats. The COBIGA project near La Gamba, in the Golfo Dulce region of Costa Rica, aims at reforestation of lowland sites with native tree species. Ants, as ubiquitous and highly abundant terrestrial organisms, have a substantial influence on tropical ecosystems. The multiple roles include scavenging, predation, herbivory, and mutualistic interactions. We examined ant community responses to reveal the status of community regeneration and functional integrity. We compared the composition and diversity of the ant assemblages at three different age reforestation sites (2, 8, and 10 years old) with those at an old-growth forest as a reference site. By offering canned tuna fish at ground level along replicated transects, we observed 43 ant species representing six functional groups during the 2 months of sampling. Most of the observed ant species were omnivorous, but old-growth forests harbored a substantial number of other functional groups, such as generalized predators, arboreal predators, and arboreal omnivores. In contrast, the youngest reforestation site harbored a severely impoverished ant assemblage comprising mostly generalized polygynous and polydomous ant species from lower trophic levels. The within-site heterogeneity of the ant assemblages increased from the youngest to the oldest forest. In addition, our results show the importance of monitoring the progress of forest recovery to avoid the spread of invasive species into primary habitats.

Earthworm dynamics in relation to alterations of vegetation: effects of oil palm in comparison to rubber and natural forest in tropical Ultisols

Earthworm dynamics in relation to alterations of vegetation: effects of oil palm in comparison to rubber and natural forest in tropical Ultisols

Geographic and Climatic Variation in Resin Components and Quality of Pinus oocarpa in Southern Mexico Provenances.

In Mexico, there is a deficit in the production of pine resin, because it relies on natural forests only. Therefore, it is necessary to select provenances and phenotypes of potential species such as P. oocarpa. The objective was to determine the difference between provenances and the variation in resin components and quality, as well as the effect of geographic and climatic factors. Resin from five provenances was collected from southern Mexico. The percentage of rosin, turpentine and water was obtained, as well as the acidity and saponification index. P. oocarpa resin had 80.94% rosin, 7.7% turpentine and 11.49% water. The saponification and acidity index was 125.47 and 117.49 mg KOH.g-1, respectively. All variables showed differences (p ≤ 0.0001) between provenances. The provenance contributed between 6.44 and 11.71% to the total variance, the error contributed between 88.29 and 93.56%. Geographic and climatic variables only had an effect on the percentage of turpentine; the correlation was negative with altitude and longitude, but positive with temperature and precipitation. The results allow defining seed collection sites for resin plantations and orienting the selection for a P. oocarpa improvement program.

Evidence for regional-scale declines in carabid beetles in old lowland beech forests following a period of severe drought

ContextEvidence for declines in insect populations is growing with climate change being one suspected driver. Forests, however, are still underrepresented in the relevant research. Recent droughts (2018–2020) have severely affected forests in Central Europe and have been linked to declines in carabid abundance, biomass as well as changes in species traits at the local scale.ObjectiveWe tested drought effects on forest carabids at regional scale. We additionally investigated whether variability in drought effects could be explained with the initial community composition and the local environmental context.MethodsWe used generalized linear mixed models to compare data from 1999 to 2001 and 2020 to 2022 across eleven old beech forest sites of high conservation interest in North-East Germany and investigated changes in carabid abundance, biomass, Hill numbers and selected species traits. We then tested additional community-related and environmental predictors to explain spatial variability in changes in biomass.ResultsWe found significant declines in biomass of 65% and in abundance of 51%. There were no significant changes in Hill numbers. We found consistent evidence that declines affected especially larger and less mobile species. Declines and changes in species traits also occurred in strictly protected old-growth beech forests. Among environmental predictors, landscape composition explained local variability in biomass declines best with stronger decline at forest sites with less forest area in their vicinity.ConclusionsOur findings reveal large-scale declines in forest carabids in the context of recent droughts and highlight the exceptional role of landscape composition in this regard. Future insect conservation strategies need to incorporate the landscape context and potential exposure to extreme weather.

Disentangling the invasion process of subtropical native forests of Uruguay by the exotic tree Ligustrum lucidum: establishment and dominance determinants

BackgroundWhat factors, processes and mechanisms regulate invasive processes and their effects? This is one of the main questions addressed by the ecology of biological invasions. Ligustrum lucidum, a tree species native to East Asia, became an aggressive invader of subtropical and temperate forests around the world. We analyzed here the L. lucidum invasion in Uruguayan forests to determine the factors controlling two stages of the invasive process, the establishment, and the dominance. Establishment was assessed by the occurrence, measured in 1525, 1 × 1 km-cells, and dominance by remotely measuring the L. lucidum coverage at the forest canopy in 5554, 1 × 1 km-cells. The occurrence and dominance were modeled using Generalized Linear Models in function of independent environmental and geographic variables.ResultsLigustrum lucidum has become established in 13.4% of the Uruguayan forests and has dominated the forest canopy in 1.2%. Our models explained 45% and 35% of the occurrence and dominance spatial variance respectively and detected in both cases strong diffusion patterns from the S-SW region to rest of Uruguay. Occurrence increased mainly in function of urban areas, and with the proximity to towns, probably because L. lucidum trees planted in gardens are seed sources, and near railways and highways, that could function as biological corridors. Occurrence also increased in loamy soils and near rivers, suggesting moisture conditions are favorable for establishment. Dominance increased with reduced forest area, in high productive soils and at higher altitudes. Moreover, dominance increased near urban areas, roads, and railways, as well as in highly afforested landscapes, and in loamy and low-rockiness soils.ConclusionsThe invasion of Uruguayan forests by L. lucidum is in the spread and impact stages, currently in expansion from the invasion focus on the S-SW region, where the oldest urbanizations are settled, towards the rest of the country. The geographic proximity to the invasion focus is currently the main predictor of both L. lucidum establishment and dominance. Additionally, whereas establishment is manly facilitated by human infrastructures improving propagule pressure and dispersion, dominance is enhanced in small or fragmented forest patches, in rich-nutrient soils, and at higher altitudes, suggesting ecosystem resistance is also operating.

Post-Logging Canopy Gap Dynamics and Forest Regeneration Assessed Using Airborne LiDAR Time Series in the Brazilian Amazon with Attribution to Gap Types and Origins

Gaps are openings within tropical forest canopies created by natural or anthropogenic disturbances. Important aspects of gap dynamics that are not well understood include how gaps close over time and their potential for contagiousness, indicating whether the presence of gaps may or may not induce the creation of new gaps. This is especially important when we consider disturbances from selective logging activities in rainforests, which take away large trees of high commercial value and leave behind a forest full of gaps. The goal of this study was to quantify and understand how gaps open and close over time within tropical rainforests using a time series of airborne LiDAR data, attributing observed processes to gap types and origins. For this purpose, the Jamari National Forest located in the Brazilian Amazon was chosen as the study area because of the unique availability of multi-temporal small-footprint airborne LiDAR data covering the time period of 2011–2017 with five data acquisitions, alongside the geolocation of trees that were felled by selective logging activities. We found an increased likelihood of natural new gaps opening closer to pre-existing gaps associated with felled tree locations (<20 m distance) rather than farther away from them, suggesting that small-scale disturbances caused by logging, even at a low intensity, may cause a legacy effect of increased mortality over six years after logging due to gap contagiousness. Moreover, gaps were closed at similar annual rates by vertical and lateral ingrowth (16.7% yr−1) and about 90% of the original gap area was closed at six years post-disturbance. Therefore, the relative contribution of lateral and vertical growth for gap closure was similar when consolidated over time. We highlight that aboveground biomass or carbon density of logged forests can be overestimated if considering only top of the canopy height metrics due to fast lateral ingrowth of neighboring trees, especially in the first two years of regeneration where 26% of gaps were closed solely by lateral ingrowth, which would not translate to 26% of regeneration of forest biomass. Trees inside gaps grew 2.2 times faster (1.5 m yr−1) than trees at the surrounding non-gap canopy (0.7 m yr−1). Our study brings new insights into the processes of both the opening and closure of forest gaps within tropical forests and the importance of considering gap types and origins in this analysis. Moreover, it demonstrates the capability of airborne LiDAR multi-temporal data in effectively characterizing the impacts of forest degradation and subsequent recovery.

Use of Doppler velocity radars to monitor and predict debris and flood wave velocities and travel times in post-wildfire basins

The magnitude and timing of extreme events such as debris and floodflows (collectively referred to as floodflows) in post-wildfire basins are difficult to measure and are even more difficult to predict. To address this challenge, a sensor ensemble consisting of noncontact, ground-based (near-field), Doppler velocity (velocity) and pulsed (stage or gage height) radars, rain gages, and a redundant radio communication network was leveraged to monitor flood wave velocities, to validate travel times, and to compliment observations from NEXRAD weather radar. The sensor ensemble (DEbris and Floodflow Early warNing System, DEFENS) was deployed in Waldo Canyon, Pike National Forest, Colorado, USA, which was burned entirely (100 percent burned) by the Waldo Canyon fire during the summer of 2012 (MTBS, 2020).Surface velocity, stage, and precipitation time series collected during the DEFENS deployment on 10 August 2015 were used to monitor and predict flood wave velocities and travel times as a function of stream discharge (discharge; streamflow). The 10 August 2015 event exhibited spatial and temporal variations in rainfall intensity and duration that resulted in a discharge equal to 5.01 cubic meters per second (m3/s). Discharge was estimated post-event using a slope-conveyance indirect discharge method and was verified using velocity radars and the probability concept algorithm. Mean flood wave velocities – represented by the kinematic celerity ck=2.619meterspersecond,m/s±0.556percent and dynamic celerity cd=3.533m/s±0.181percentandtheiruncertainties were computed. L-moments were computed to establish probability density functions (PDFs) and associated statistics for each of the at-a-section hydraulic parameters to serve as a workflow for implementing alert networks in hydrologically similar basins that lack data.Measured flood wave velocities and travel times agreed well with predicted values. Absolute percent differences between predicted and measured flood wave velocities ranged from 1.6 percent to 49 percent and varied with water slope, hydraulic radius, and depth. The kinematic celerity was a better predictor for steep slopes and wide flood plains associated with the Upper Waldo and Middle Waldo radar streamgages; whereas, the dynamic celerity was a better surrogate for shallow slopes and incised channels such as the Lower Waldo radar streamgage.The method demonstrates the potential extensibility of a post-wildfire warning system by (1) leveraging multiple systems (i.e., weather radar, near-field velocity and stage radars, and rain gages) for accurate and timely warnings of debris and floodflows, (2) establishing an order of operations to site, install, and operate near-field radars and conventional rain gages to record floodflows, forecast travel times, and document geomorphic change in this basin and hydrologically similar basins that lack data, and (3) communicating data operationally with the Colorado Department of Transportation engineering staff, National Weather Service forecasters, and emergency managers.

Трансформация почвенных зооценозов в первый год после рубки леса

Soil macrofauna of primary forests of the middle taiga is characterized by high abundance (94.6–146.6 ind./m2), taxonomic richness (10–14 taxa), dominance of Diptera and Cantharidae larvae, similarity of fauna composition (J=0.60–0.65), with a ratio of detritivores and predators equal to 1:1, aggregated or random horizontal distribution. The total density of invertebrates sharply decreases (4.5–26.8 ind./m2) in the first year after deforestation. Some taxa are eliminated from the fauna, 4–7 taxa are remained. The ratio of trophic groups is changed. The distribution of invertebrates in space is disturbed. Soil macrofauna of clear-cutting areas (CCA) retains a taxonomic structure close to the control sites (C). The taxonomic and trophic structure of soil macrofauna is more disturbed on the logging corridors (LC) with three (3LC) and ten (10LC) penetrations of aggregate equipment, recultivated (RLC) and main (MLC) logging corridors. Thus, the density of Diptera larvae is high on the logging corridors. The above are temporary r-strategists characteristic for the disturbed environment. And the ratio of detritivores and predators on the technological sites “C – CCA – 3LC – 10LС – RLC – MLC” is 1:1 – 3:1 – 7:1 – 10:1 – 13:1 – 15:1. A trend towards an increase in the density of detritivores on the recultivated (RLC) and main (MLC) logging corridors was noted. The decrease of the total density of macrofauna and the declining of systematic groups of the clear-cutting areas is not so significant due to the fact that the litter on these sites is almost completely preserved after felling. The low diversity of soil macrofauna on the logging corridors can be explained by a change in the natural conditions for the existence of invertebrates due to the compaction of the upper soil horizons, the partial disappearance of the litter, the appearance of a mineralized soil layer as top horizon, and a rapid change in humidity. Significant changes in the abundance, composition, and ratio of trophic groups of invertebrates indicate the collapse of soil macrofauna, the loss of important groups of destructors and predators from food webs, and a decrease in the quality of their functions at the initial stage of restorative succession, in the first year after deforestation.

Sequence and structure analyses of lytic polysaccharide monooxygenases mined from metagenomic DNA of humus samples around white-rot fungi in Cuc Phuong tropical forest, Vietnam

Background White-rot fungi and bacteria communities are unique ecosystems with different types of symbiotic interactions occurring during wood decomposition, such as cooperation, mutualism, nutritional competition, and antagonism. The role of chitin-active lytic polysaccharide monooxygenases (LPMOs) in these symbiotic interactions is the subject of this study. Method In this study, bioinformatics tools were used to analyze the sequence and structure of putative LPMOs mined by hidden Markov model (HMM) profiles from the bacterial metagenomic DNA database of collected humus samples around white-rot fungi in Cuc Phuong primary forest, Vietnam. Two genes encoding putative LPMOs were expressed in E. coli and purified for enzyme activity assay. Result Thirty-one full-length proteins annotated as putative LPMOs according to HMM profiles were confirmed by amino acid sequence comparison. The comparison results showed that although the amino acid sequences of the proteins were very different, they shared nine conserved amino acids, including two histidine and one phenylalanine that characterize the H1-Hx-Yz motif of the active site of bacterial LPMOs. Structural analysis of these proteins revealed that they are multidomain proteins with different functions. Prediction of the catalytic domain 3-D structure of these putative LPMOs using Alphafold2 showed that their spatial structures were very similar in shape, although their protein sequences were very different. The results of testing the activity of proteins GL0247266 and GL0183513 show that they are chitin-active LPMOs. Prediction of the 3-D structures of these two LPMOs using Alphafold2 showed that GL0247266 had five functional domains, while GL0183513 had four functional domains, two of which that were similar to the GbpA_2 and GbpA_3 domains of protein GbpA of Vibrio cholerae bacteria. The GbpA_2 - GbpA_3 complex was also detected in 11 other proteins. Based on the structural characteristics of functional domains, it is possible to hypothesize the role of chitin-active GbpA-like LPMOs in the relationship between fungal and bacterial communities coexisting on decomposing trees in primary forests.

Acoustic phenology of tropical resident birds differs between native forest species and parkland colonizer species

Most birds are characterized by a seasonal phenology closely adapted to local climatic conditions, even in tropical habitats where climatic seasonality is slight. In order to better understand the phenologies of resident tropical birds, and how phenology may differ among species at the same site, we used ~70 000 hours of audio recordings collected continuously for two years at four recording stations in Singapore and nine custom‐made machine learning classifiers to determine the vocal phenology of a panel of nine resident bird species. We detected distinct seasonality in vocal activity in some species but not others. Native forest species sang seasonally. In contrast, species which have had breeding populations in Singapore only for the last few decades exhibited seemingly aseasonal or unpredictable song activity throughout the year. Urbanization and habitat modification over the last 100 years have altered the composition of species in Singapore, which appears to have influenced phenological dynamics in the avian community. It is unclear what is driving the differences in phenology between these two groups of species, but it may be due to either differences in seasonal availability of preferred foods, or because newly established populations may require decades to adjust to local environmental conditions. Our results highlight the ways that anthropogenic habitat modification may disrupt phenological cycles in tropical regions in addition to altering the species community.