National Forest Research Articles

The transition from shifting cultivation to indigenous agroforestry as nature-based solution for land restoration in the Indian Eastern Himalayas

In the Indian Eastern Himalayas, shifting cultivation has long been a major cause of land degradation. However, indigenous communities, like the Hmar, have successfully transitioned from shifting cultivation to agroforestry systems such as pineapple agroforestry, leading to land restoration and increased household incomes. Despite these positive outcomes, little is known about how soil health indicators change during this transition. Thus, the present study aimed to investigate changes in selected soil health indicators and erodibility across different age classes of pineapple agroforestry systems (<5, 5–10, 11–15, and > 15 years old) compared to shifting cultivation and nearby natural forests. Soil samples were collected from six sites, including different stages of pineapple agroforestry systems, shifting cultivation phases, and a natural forest. At each site, three (10 × 10 m) quadrats were selected, and two (1 × 1 × 1 m) vertical soil pits were dug in each quadrat, sampling soil depths from 0 to 100 cm. The transition from shifting cultivation to pineapple agroforestry improved soil organic carbon (SOC) and stratification ratios while reducing soil erodibility. SOC stocks were estimated at 182.7 Mg C/ha for natural forest land and 188.2 Mg C/ha for the cropping phase in shifting cultivation. On the other hand, estimated SOC stocks for < 5, 5–10, 11–15 and > 15 years old stands of pineapple agroforestry system were 169.7 Mg C/ha, 157.2 Mg C/ha, 168.9 Mg C/ha and 177 Mg C/ha respectively. Thus, the estimated SOC stocks under > 15 years of pineapple agroforestry were comparable with adjacent natural forest land. The stratification ratios (SR > 2) for SOC and macronutrients indicated better soil quality in the pineapple agroforestry system than in the cropped land. The clay and modified clay ratios decreased with increasing age of pineapple agroforestry system stands. The highest clay ratio was recorded in the topsoil of < 5-year-old pineapple agroforestry system, indicating a greater risk of exposure to rainfall events than in natural forest land and the cropping phase in the shifting cultivation cycle. It is concluded that transitioning from shifting cultivation to a pineapple agroforestry is a nature-based solution to restore degraded lands and presents an excellent opportunity for sustainable soil health and carbon sink management.

Phoenix ×arehuquensis nov. hybr. (Arecaceae): The hybrid of P. canariensis × P. reclinata in garden and forest

Phoenix reclinata Jacq. is a palm species native to tropical and southern Africa, extending to Madagascar, where its natural populations are exploited for sap and fibre. Widely embraced as an ornamental palm in gardens within warm zones abroad, it has established itself as an integral part of horticultural landscapes.On the other hand, Phoenix canariensis H. Wildpret is an endemic species found in the Canary Islands (Spain), forming extensive palm forests. Since the 1850s, it has emerged as the predominant ornamental Phoenix palm tree. Interestingly, in various regions, the natural habitat of one species intersects with cultivated individuals of the other. For instance, in southern Africa, where P. reclinata is indigenous and P. canariensis is exotic, occasional spontaneous hybrids have been reported. These hybrids have also been observed in Florida and California (USA), where both species are cultivated.In this publication, we formally introduce a new hybrid: Phoenix ×arehuquensis nov. hybr., originating from the Canary Islands. Additionally, we explore its potential impact on natural palm forests.

Damage prediction for planted longleaf pine in extreme winds

Severe wind disturbances are forecast to increase in frequency and intensity with climate change putting forest trees at greater risk of wind damage. Of particular concern are mature and old-growth forests of wind-prone regions which host considerable biodiversity. Landscape configuration, stand structure, and tree characteristics affect susceptibility to wind damage. In managed forests and restoration contexts, these factors could be manipulated to enhance resistance to severe wind events. We measured landscape, stand, and tree characteristics, and damage in longleaf pine (Pinus palustris Mill.) forests in southwest Georgia and Northwest Florida affected by Hurricane Michael (2018) and used these data to model wind damage. We hypothesized that wind damage would increase with wind exposure and decrease with diameter-to-height ratio (taper). We found that lower wind exposure and higher taper resulted in substantially lower wind damage. We conclude that maintaining lower stand density during stand development could reduce wind damage by increasing individual tree resistance to wind. Management and restoration activities that increase resilience to threats from extreme weather can help maintain persistence and landscape restoration of global biodiversity hotspots in wind-prone regions.

Loquat (Eriobotrya japonica) fruit consumption and preference by cloud forest birds: Implications for woody native species regeneration

Secondary forests from abandoned shade coffee plantations are commonly found close to Neotropical cities. These peri-urban forests provide important environmental services; however, their abandonment and proximity to the city can promote an increase of exotic species that could potentially change the structure and function of the system by creating novel ecosystems. The loquat (Eriobotrya japonica) is a tree native to Asia and is recognized as a potentially invasive species in the tropical montane cloud forest region of Central Veracruz, Mexico. We analyzed the consumption of and preference for loquat fruits in cloud forest frugivorous birds. In November 2020, we established six feeding stations with camera traps in a peri-urban cloud forest fragment in Xalapa, Mexico. To determine which bird species could consume and disperse E. japonica, fruits of this and another four native species (Psychotria nervosa, Hoffmannia excelsa, Picramnia antidesma, and Xylosma flexuosa) were exposed separately. After 444 camera-days, we recorded eight frugivorous bird species, seven of which consumed E. japonica fruits. Chlorospingus flavopectus was the only species to present a level of loquat fruit consumption greater than that expected by chance. We conducted experiments to assess whether the birds preferred to consume E. japonica fruits compared to those from three native species (Cestrum miradorense, P. nervosa, and X. flexuosa) that were offered simultaneously. All bird species exclusively consumed E. japonica fruits when contrasted against P. nervosa or X. flexuosa. The only native species fruits that were consumed were those of C. miradorense, although the birds also preferred to consume loquat fruits rather than this native species. The loquat therefore represents an important food resource and could act to influence the consumption and dispersal of native cloud forest plant species. The implications for cloud forest management are discussed.

Plantiness, Multispecies Conviviality and Changing Human-Plant Geographies

The essay examines changing human-plant geographies in Kodagu, situated in the Western Ghats in southern India. Paying attention to Kodagu helps investigate how plantiness impacts resource politics in indigenous landscapes across pre-colonial, colonial and post-colonial timeframes. This essay will study Sarita Mandanna’s Tiger Hills (2010) and Kavery Nambisan’s The Scent of Pepper (2010) from a bioregional perspective to understand the importance of native plants, forests, vegetal and feral spaces across Kodagu’s shifting societies and timeframes and examine how human-plant encounters redefine the role of plants in Kodagu’s more-than-human geographies. With a particular focus on the Kodava ritual of Kailpodh, this essay will investigate how humans often classify plants as native, invasive, weeds, sacred and unwanted, depending on their impact on human social life, and how ritualising plants such as rajakirita (Gloriosa superba) helps to reinhabit Kodagu and deepens the Kodava human-plant interaction across space and time.

Refining greenhouse gas emission factors for Indonesian peatlands and mangroves to meet ambitious climate targets

For countries' emission-reduction efforts under the Paris Agreement to be effective, baseline emission/removals levels and reporting must be as transparent and accurate as possible. For Indonesia, which holds among the largest area of tropical peatlands and mangrove forest in the world, it is particularly important for these high-carbon ecosystems to produce high-accuracy greenhouse gas inventory and to improve national forest reference emissions level/forest reference level. Here, we highlight the opportunity for refining greenhouse gas emission factors (EF) of peatlands and mangroves and describe scientific challenges to support climate policy processes in Indonesia, where 55 to 59% of national emission reduction targets by 2030 depend on mitigation in Forestry and Other Land Use. Based on the stock-difference and flux change approaches, we examine higher-tier EF for drained and rewetted peatland, peatland fires, mangrove conversions, and mangrove on peatland to improve future greenhouse gas flux reporting in Indonesia. We suggest that these refinements will be essential to support Indonesia in achieving Forest and Other Land Use net sink by 2030 and net zero emissions targets by 2060 or earlier.

Analyzing temporal and spatial forest carbon storage using Google Plus Code: a case study of Zijin Mountain National Forest Park, China.

It is always a challenging job to compare forest resources as there is not a standardized spatial unit with location information. Google Plus Code, the newest alphanumeric geocoding system, uses 20 specifically selected letters and numbers to assign a unique global ID to every cell at different levels of a hierarchical grid system which is established based on latitude and longitude. It can be used as a standardized, unique global geospatial unit to segment, locate, quantitate, evaluate, and compare natural resources with area, boundary, and location information embedded. For this proof-of-concept case study, forest inventory data from 1987, 2002, and 2019 for the Zijin Mountain National Forest Park in Jiangsu Province, China was analyzed based on Google Plus Code grid/cell. This enabled the quantification of carbon storage at each cell allowing for the comparison of estimated carbon storage at same or different locations over time. This methodology is used to quantify the impacts of changing forest conditions and forest management activities on carbon storage with high spatial accuracy through the 32-year study period. Furthermore, this technique could be used for providing technical support and validation of carbon credit quantification and management.

Geospatial Inventory of the Galakand Forestry Area Utilizing GIS Database and Remote Sensing Techniques

This study investigated the dramatic reduction of forested areas in Azerbaijan, exceeding 50% over the past two centuries, largely due to increased wood production. Focusing on the period between 1880 and 1990, it analyzed the impact of timber harvesting on the composition of dominant tree species, with a special focus on beech trees, in the Galakand forestry area. Utilizing GIS databases and remote sensing techniques, the research assessed the changes in forest cover and species distribution, highlighting the critical transition from lush beech and oak forests to areas dominated by hornbeam, east hornbeam, oak-hornbeam, and juniperus-bush light forests. The study demonstrated the negative consequences of historical overexploitation, advocating for forest farming practices that promote the recovery and preservation of native forest ecosystems. Key findings revealed a marked decline in valuable wood species due to intensive logging activities, particularly between 1880 and 1914, and the detrimental effects of forest renewal cabins established from 1930 to 1970. The outlined measures in the study highlighted that the forest primarily comprises wooded areas (reserves with a completeness of 0.1-0.2, clearings, and clearings), non-forest lands repurposed as pastures and forested pastures with a density ranging from 0.3 to 0.4. Overall, the findings underscore the importance of sustainable forest management practices to reverse the adverse effects of historical overexploitation and preserve the biodiversity of Azerbaijan's ecosystems. The paper emphasized the necessity of sustainable forest management to reverse the damage and protect Azerbaijan's biodiversity to enhance measures for sustainable forestry, along with the critical role of advanced GIS and remote sensing in monitoring and conserving forest resources.

Unique bird diversity in an Ethiopian church forest

AbstractToday, most of Ethiopia’s church forests are small forest patches surrounded by a degraded and anthropogenically modified landscape, mostly arable land. Nevertheless, these forest islands may still provide valuable habitats for typical forest species. It remains questionable whether these habitat remnants provide sufficient resources for forest species to successfully reproduce and persist in the long run. In this study, we assessed bird species based on point-counts in and around Tara Gedam Church Forest in northern Ethiopia. We observed birds in typical natural evergreen Afromontane forest (forest interior and forest edge) and in anthropogenic habitats, the semi-natural shrublands, agricultural land, and Eucalyptus tree plantations. We assigned ecological and behavioural characteristics to each of the bird species observed. Our results point to a specific bird community restricted to the forest interior and characterized by forest generalists and forest specialist birds. Along the forest edge, a mix of forest generalists and species of the open landscape can be found, creating mixed communities with high species overlap. The highest number of species was observed at the forest edge and in semi-natural shrubland, where both, open-land and forest species were found. On the other hand, the total number of species in the forest interior was comparatively low, with insectivorous and frugivorous typical forest species. Our results underline the fact that even small forest remnants are important for the conservation of forest species, which do not evade surrogate forest habitats.

Evaluating the occurrence and spatial patterns of soil water repellency in the Deschutes National Forest, Oregon

AbstractHigh levels of soil water repellency (SWR) can hinder water infiltration and increase surface soil erosion risk and runoff. Although SWR occurs naturally in many areas, it is often patchy and does not impede water movement. However, fire can increase the connectedness and extent of SWR leading to topsoil loss, nutrient limitations, increased root water stress, and ultimately slower ecosystem recovery. This study examines the naturally hydrophobic soils of Oregon's Deschutes National Forest following the 2020 Green Ridge Fire to (1) examine the relationship between SWR and management‐relevant burn severity classes, (2) quantify an appropriate spatial scale over which to evaluate SWR properties, and (3) determine which environmental factors drive patterns in SWR. We found that the top 1–3 cm of soil became less hydrophobic after fire, while the profile to about 10 cm became more uniformly hydrophobic. This could indicate that surface soil is more prone to post‐fire erosion in burned areas. However, predicting SWR is still challenging. While burn severity and environmental metrics did statistically account for some variation in SWR following fire, the range of SWR spatial autocorrelation was at best a few meters. Due to this fine‐scale variation, future work should focus on determining an efficient post‐fire soil evaluation protocol with adequate density and scale of sampling while also incorporating the influence of environmental factors to inform management decisions.

Plant Community Composition and Structural Pattern Dynamics in Robe-Raya Natural Forest, Southeast Ethiopia

Due to its fortuitous mix of geography, terrain, and geology, Ethiopia is the home of unique assemblages of rich biodiversity. However, this impressive biological diversity is increasingly threatened by the combined effects of different drivers before they are sufficiently investigated. The present work was carried out in Robe-Raya Natural Forest, located in Southeast Ethiopia, with the intention of examining plant community formation and structural dynamics of the forest species. Sixty (20 m × 20 m) quadrats were placed at 100 m distance along eleven east-west directed transect lines systematically. In order to gather juvenile’s data, five subquadrats (2 m × 2 m) were established within the main quadrat, distributed at each corner and middle. In each quadrat, all woody species were recorded and counted; diameter (DBH) and height were measured using tape meter and a hypsometer, respectively, and cover abundance was recorded (in %). Cluster analysis was computed using R-Package to map-out the community types. Species diversity and composition among community types were computed using the Shannon-Wiener index and Sorenson’s coefficient, respectively. Frequency, density, height, DBH, basal area, and IVI were used to analyze structural dynamics. Age-class density ratios were used to examine the regeneration status. Ninety-four woody plant species belonging to 39 families were documented. Asteraceae was the most species-rich family (10 species). The common growth form was shrubs (44.7%) followed by trees (41.5%). Cluster analysis produced four community types. In total, the species diversity and evenness were 3.75 and 0.88, respectively. The forest density and basal area were 1183.3 stems/ha and 57.52 m2·ha−1, respectively. Structural dynamics analyses demonstrated that the forest was composed of, largely, young trees and shrubs and under fair regeneration status. Certain species that have been identified to have low IVI and poor regeneration status should be prioritized for conservation.

How natural are the forests in Rajiv Gandhi (Nagarhole) Tiger Reserve? A multi-source data approach.

This study aimed to monitor long-term land use dynamics for understanding the natural forestintegrity and intactness of the Rajiv Gandhi (Nagarhole) Tiger Reserve (RTR) pre- and post-declarations as TR. We employed multi-source data from Survey of India Toposheets (1:50k), Landsat-7, and Sentinel-2A along with Global Ecosystem Dynamics Investigation (GEDI) vegetation canopy height (10m) data, a high-spatial resolution CORONA (1970) images and temporal Google Earth Pro images for mapping and validation. To map vegetation type, land use and land cover (LULC) transitions, and fragmentation (1980-2022) we employed a hybrid classification approach. This study also analyzed decadal forest dynamics within TRsusing India's State of Forest Reports (ISFR). Findings reveal significant forest fragmentation and habitat loss due to anthropogenic activities in the TR. Mono-plantations (teak and eucalyptus) were found inside TR, while the buffer (1km) was occupied mainly with coffee and orange plantations which indicates the prevalence of human footprint. The overall accuracy of the current period (2022) is 92.0% with a kappa coefficient value of 0.90. These plantations were established during the British colonial period (early 1900s) for commercial purposes by clearing natural forests. The present study highlights that mono-plantations have not transitioned into natural forests even after a century. This lack of transformation could potentially compromise the integrity of the native forest. Despite its ecological significance, RTR has experienced disturbance due to human footprint. Hence, there is a need for an action plan to protect this vital landscape by replacing mono-plantations with suitable species to preserve the integrity of the forest. These issues extend beyond the protected areas, impacting surrounding regions and require regular monitoring. The proposed methods can be applied to other protected areas facing similar problems in the countryand world.

A new species and new records of the spider genus Dubiaranea (Araneae, Linyphiidae) from southern Brazil and Uruguay, with an analysis of the potential distribution of the species

Dubiaranea magatama Cajade, Hagopián &amp; Rodrigues n. sp. is described from Uruguay, and southern Brazil based on males and females from several types of native forests, and a potential distribution for this species is modeled. The predicted model for this species indicates a Pampean province and southern Atlantic Forest biome distribution. Three variables contributed significantly to the model with positive influence: the spatial component, the proximity to large rivers, and the tree cover. Also, we provide new records of Dubiaranea difficilis (Mello-Leitão 1944) for Uruguay and a model of its potential distribution was performed. It showed that tree cover, the proximity to large rivers, the spatial component and precipitation/evapotranspiration constraints were recovered for the model with positive influence, expanding the potential distribution area previously proposed.

Soil Fertility Assessment and Mapping under Different Land Use Types along Toposequence at Danka Watershed in Dinsho Districts of Bale Highland Oromia, Southeastern Ethiopia

Soil fertility assessment and mapping bases, to increase fertilizer usage efficiency, decision-makers, planners, and soil management in undulating slopes farming of Ethiopian highlands like Bale Highland. The study aimed to assess and map soil fertility status along toposequence under different land use types at the Danka watershed of Dinsho District Bale Highland, Southeastern Ethiopia. Following the initial reconnaissance field survey, 54 composite soil samples were prepared from the three land use types (natural forest, grazing, and cultivated) at three slope positions lower (0 - 10%), middle (10 - 15%), and upper (15 - 30%) at a soil depth of 0 to 20 cm. Finally, the laboratory results were interpolated using the IDW interpolation technique in ArcGIS software 10.5 for the soil fertility status map and further analyzed using R software 4.1.1 Version for mean separation. The study findings indicate that the soil texture class of the study was loam to clay loam, clay loam, and clay to clay loam at the upper, middle, and lower slope positions, respectively. The finding revealed that the values varied from 5.81 – 6.66, 2.07 – 6.25%, 0.13 – 0.71%, 2.83 – 17.56 gm/kg, and 14.04 -38.80 cmol (+)/kg) for the soil pH, organic matter, total nitrogen, available phosphorus, and CEC, respectively. In this study, most of the soil fertility status of the Danka watershed was as follows: natural forest &gt; grassland &gt; cultivated land use types and lower slope &gt; middle slope &gt; upper slope positions. In conclusion, the main factors contributing to the area's declining soil fertility status were monocropping, total crop residue removal, soil erosion, nutrient leaching, and inadequate soil management. The results of the current study offer the basis for the work of farmers, planners, decision-makers, and other agriculture-related stakeholders. Integrated soil fertility management with biophysical soil conservation measures is advisable for cultivated land at all slope positions. Further, a study on slope position-based crop response fertilizer rating for agricultural precision and ensuring food security is recommended in undulating fields of the Danka watershed.

Maximizing carbon sequestration potential in Chinese forests through optimal management

Forest carbon sequestration capacity in China remains uncertain due to underrepresented tree demographic dynamics and overlooked of harvest impacts. In this study, we employ a process-based biogeochemical model to make projections by using national forest inventories, covering approximately 415,000 permanent plots, revealing an expansion in biomass carbon stock by 13.6 ± 1.5 Pg C from 2020 to 2100, with additional sink through augmentation of wood product pool (0.6-2.0 Pg C) and spatiotemporal optimization of forest management (2.3 ± 0.03 Pg C). We find that statistical model might cause large bias in long-term projection due to underrepresentation or neglect of wood harvest and forest demographic changes. Remarkably, disregarding the repercussions of harvesting on forest age can result in a premature shift in the timing of the carbon sink peak by 1–3 decades. Our findings emphasize the pressing necessity for the swift implementation of optimal forest management strategies for carbon sequestration enhancement.

Carbon Sequestration Dynamics in Peri-Urban Forests: Comparing Secondary Succession and Mature Stands under Varied Forest Management Practices

This study examines the impact of silvicultural and land-use management practices on carbon sequestration in peri-urban forest ecosystems, with a particular focus on human-induced carbon dynamics. The study area’s complex profile spans from a compact native forest to varying degrees of fragmentation. This included areas undergoing secondary succession forest without silvicultural interventions (No-SI) alongside sites subjected to high-intensity (High-SI) and low-intensity silvicultural interventions (Low-SI). The research assessed carbon stocks and sequestration in different carbon pools (living biomass, dead organic matter and soil) using field data, allometric equations and laboratory analysis. Findings reveal a significant correlation between the intensity of anthropogenic interventions and variations in carbon stocks. The CASMOFOR model facilitated the reconstruction of carbon stock and carbon-stock change dynamics over four decades (1980–2022), showing disparities in carbon storage capabilities linked to the structural characteristics of the sites. The Low-SI site had the highest carbon stock in all carbon pools (378 tonnes C ha−1), which is more than double compared to High-SI (161 tonnes C ha−1) or No-SI sites (134 tonnes C ha−1). However, the secondary succession forest (No-SI) demonstrated the highest annual carbon stock change (4.4 tonnes C ha−1 year−1), two times higher than the Low-SI mature stand (2.2 tonnes C ha−1 year−1), emphasising the resilience of forest ecosystems to recover and sustain carbon sequestration capacities after harvesting if forest land use remains unchanged. The study underscores the significant importance of anthropogenic interventions on carbon dynamics, especially for living tree biomass, which has consequences in enhancing carbon sequestration and contributing to emission reduction targets.

Climate variability and river flow changes in Wundanyi sub-catchment of Taita hills, Kenya

&lt;p&gt;Wundanyi sub-catchment of Taita hills is experiencing a high rate of deforestation due to the conversion of all its original forestland to agriculture and settlement during the last century. The landscape dynamics coupled with rainfall fluctuations in these critical ecosystems may significantly affect water resource distribution and food security in Taita Taveta County and its environs. This study aimed to establish the trends of selected hydroclimatic variables in Wundanyi sub-catchment from 1970 to 2030 and their specific and combined effects on surface runoff and streamflow in the same period. The analysis was based on statistical trend analysis and dynamic landscape modelling using both historical and primary hydroclimatic data from Wundanyi and Voi weather stations. Results show highly variable mean seasonal and annual values of temperature, rainfall, runoff and discharge in both Wundanyi and Voi weather stations. Increasing mean temperatures and rainfall were observed during the long dry season (JJAS), while decreasing seasonal discharges were observed during both the JJAS dry season and the OND short rainy season. These anomalies were pronounced in 1980–1981, 1986–1987 and 1992–1993, probably due to both global and local environmental changes affecting Taita Hills in general and Wundanyi sub-catchment in particular. The predicted effects of rainfall fluctuation were supported by declining surface runoff of 1.3% during JJAS, and an increase of 0.8% during the OND, with similar effects on river discharges. The combined effects of climate variability and Land use and cover changes (LUCC) on surface runoff were estimated to an increase of 200 mm during JJAS and 370 mm during OND, and while river discharges increased by 2.37 m&lt;sup&gt;3&lt;/sup&gt;/s and 1.93 m&lt;sup&gt;3&lt;/sup&gt;/s during JJAS and OND, respectively. Consequently, natural forest covers have significant control effects on surface runoff and can boost river discharges amid diverse agricultural cropping practices. Hence, crop diversification, agroforestry, and soil and water conservation structures are recommended to maintain effective control of LUCC on hydrological processes going on in Wundanyi sub-catchment.&lt;/p&gt;

Comparative analysis of sediment quality indices using different reference values in an environmental protection area in Southeastern Brazil.

Contamination of aquatic ecosystems by potentially toxic elements (PTEs) is a concerning environmental issue, given their persistence, toxicity potential, and ability to accumulate in living organisms. Several studies have been conducted to assess the contamination of aquatic ecosystems by PTEs, using pollution and ecological risk indices that rely on the concentration of these elements in aquatic sediments. However, many of these studies use global reference values for calculating the indices, which can lead to misleading interpretations due to substantial variations in PTEs concentrations influenced by the geological characteristics of each region. Therefore, the use of regional reference values is more appropriate when available. This study aimed to investigate variations in the results of five indices, employing global, regional, and quality reference values, based on sediment samples collected from rivers in the Ipanema National Forest, a protected area in Brazil exposed to various anthropogenic pressures. The results revealed that elements such as Al, Fe, and Mn exceeded the limits allowed by legislation in water samples, while As and Cr surpassed the limits in sediment samples. Comparative analysis highlighted significant discrepancies in the results of the indices when global reference values were used compared to regional and quality reference values, especially for As and Ba. Thus, this study underscores the importance of establishing specific regional values for an accurate assessment of sediment quality and the risks associated with contamination by PTEs in different regions worldwide.

Comparison of nonlinear trends and influencing factors of carbon sinks in four ecological restoration projects in China

AbstractChina's ecological restoration projects aim to safeguard natural forests, improve the ecological environment, and achieve carbon neutrality. Previous studies at multiple scales have reported that the ecological projects contributed to enhancing carbon sinks. However, the effect of these projects on the carbon sinks has remained uncertain. Thus, we conducted a comparative analysis of nonlinear trends and influencing factors of carbon sink trends in the four ecological restoration project areas. Our findings suggested that the Pearl River shelterbelt program and middle reaches of the Yellow River shelterbelt program areas have experienced significant enhancements in ecosystem carbon sinks. The carbon sink exhibiting monotonically increasing trends and decreasing to increasing trends (positive shifts) accounted for 74.48% and 71.76% in these two shelterbelt program areas, respectively. However, less than half of the carbon sinks (41.38% and 31.80%, respectively) demonstrated monotonically increasing trends or positive shifts in the Yangtze River and Three North Shelterbelt program areas. The high background value of carbon sinks played a crucial role in the monotonically increasing trends of carbon sinks in the four ecological restoration projects. Additionally, in the Pearl River program areas, economic development and urban greening promoted the monotonically increasing trends of carbon sink. In the Yellow River program areas, CO2 fertilization, appropriate warming, and increased precipitation were helpful to promote the carbon sink with monotonically increasing trends. Moreover, the positive shifts of the carbon sinks were attributed to the implementation of these two ecological restoration projects. However, the low temperature and drought hindered the enhancement of carbon sinks in the Three North program areas, and extreme climate (flood and drought) hindered it in the Yangtze River program areas. These findings can provide a comprehensive evaluation of the effectiveness of ecological restoration projects on terrestrial ecosystems and offer practical guidelines to achieve carbon neutrality.

Landscape heterogeneity increases bird functional diversity within Neotropical vineyards

AbstractConversion of lands to agroecosystems has resulted in a decline in bird biodiversity. Analyzing functional diversity is a central tool for detecting changes in the ecological functions performed by birds in these landscapes. This paper aims to investigate the responses of bird taxonomic and functional diversity to landscape heterogeneity and native forest cover in Neotropical vineyards. We sampled 19 vineyard landscapes in southeastern Brazil. These landscapes covered a gradient of forest cover and heterogeneity resulting from various land‐uses. To assess bird diversity, we considered both taxonomic diversity and functional diversity (i.e., functional richness, evenness, and divergence). To examine the potential interactions between landscapes and bird assemblages, we employed generalized linear models (GLM). Taxonomic diversity showed no correlation with any landscape metrics. On the other hand, variation in the three metrics of functional diversity was related to landscape heterogeneity. However, in heterogeneous landscapes, these communities can be structured by limiting similarity processes. We highlight the negative impact of landscape homogenization on the ecological functions performed by birds in vineyards, while finding no significant effect on species diversity. These findings can provide valuable support for the formulation of public policies aimed at striking a balance between agricultural production and biodiversity conservation.Abstract in Portuguese is available with online material.