This study unravels contrasting leaf P‐allocation patterns of deciduous Quercus in subtropical and temperate forests, which are mainly driven by global change rather than edaphic factors. It provides new avenues for exploring nutrient strategies of congeneric species growing in diverse environments.

Soil bacteria and fungi were important components of the soil ecosystem and played a significant role in carbon storage. This study examined the differences in microbial communities between monoculture and mixed forests and their effects on ecosystem functions and carbon storages. At 20 years after plantation, this study compared monoculture and mixed forests in soil carbon storages, carbon components, microbial communities, and ecosystem multifunctionality, revealing forest type effects on carbon storage and ecosystem functioning. Relative to the monoculture forest, the soil carbon storages, bacterial community diversities and stabilities, and fungal community diversities were significantly enhanced in the mixed forests. Compared to a monoculture forest, the mixed Michelia chapensis and Cunninghamia lanceolata showed a dual effect: increasing soil carbon storages (45.22

IntroductionEvaluating soil quality is essential for guiding reforestation and land management strategies, particularly in degraded Chinese fir plantations where long-term productivity and successional dynamics remain poorly understood.MethodsThis study assessed ten mixed-species planting patterns to quantify the Soil Quality Index (SQI) using a Minimum Data Set (MDS) approach, which reduces data redundancy by statistically identifying key indicators from a larger dataset, thereby effectively capturing essential soil functions, and subsequently explored the relationships between SQI and stand growth, structural diversity, biomass, net primary productivity (NPP), as well as percentage of broadleaf species (PBS).ResultsSignificant differences were observed across planting patterns in diameter at breast height (DBH), tree height (TH), stand biomass (FB), structural diversity (variation in DBH [CVD] and Gini coefficient [GiniD]), and PBS. Soil properties—including physical (soil moisture), chemical (soil organic carbon [SOC], total nitrogen [TN], total phosphorus [TP], ammonium nitrogen [NH₄⁺], nitrate nitrogen [NO₃⁻], available phosphorus [AP]), microbial (microbial biomass carbon [MBC], nitrogen [MBN], and phosphorus [MBP]), and enzymatic (e.g., peroxidase [POD], alkaline phosphatase [ALP], urease [URE])—also varied significantly. SQI values ranged from 0.42 to 0.65, with patterns Fir–Mytilaria laosensis mixed (ML), Fir–Castanopsis hystrix mixed (CH), Fir–Michelia chapensis mixed (MC), and Fir–Schima superba mixed (SS) associated with both high SQI and greater biomass. Sensitivity analysis identified Fir–Cinnamomum porrectum mixed (CP), ML, and SS as particularly responsive to hybridization. Among soil factors, URE, AP, and MBC were key drivers of productivity, while URE, AP, MBC, and POD significantly predicted the proportion of broadleaf trees. Enhanced soil quality was positively associated with increases in DBH, TH, and PBS, accelerating the successional transition from fir-dominated to broadleaf-dominated stands. However, SQI was not significantly correlated with structural diversity metrics.DiscussionThese results underscore the importance of rational species selection in restoring degraded fir plantations and demonstrate that improving soil quality is a critical mechanism promoting near-natural forest succession.

Rainwater undergoes hydrological and chemical transformations as it passes through the forest canopy. However, this process in urban forests has received less attention compared to natural ecosystems, leading to an underestimation of their purification. This study investigated precipitation and nutrient redistribution in an urban forest in Guangzhou, southern China, a characteristic subtropical region. Heavy metal concentrations in rainfall, throughfall, and stemflow were meticulously measured in 147 precipitation events and sampled from January 2020 to September 2021. A canopy budget model was employed to estimate the contribution of canopy exchange and dry deposition to the net rainfall (throughfall + stemflow) nutrient flux. The annual input of heavy metals in precipitation was 293.82 g ha⁻¹ y⁻¹, which increased to 496.08 g ha⁻¹ y⁻¹ after canopy redistribution. Of this increase, 117.73 g ha⁻¹ y⁻¹ originated from dry deposition and 84.54 g ha⁻¹ y⁻¹ from the canopy exchange process. Except for Manganese (Mn), which was absorbed by the canopy, all other elements Chromium (Cr), Copper (Cu), Arsenic (As), Caesium (Cs), Plumbum (Pb) leached from the canopy. Giving that impervious surfaces are persistent sources of metal resuspension, and depositions are efficiently recycled into respirable particles, these findings suggest that forest canopies can purify heavy metals from atmospheric deposition at a 1:2.5 area efficiency ratio relative to urban surfaces. These results not only enhance our understanding of heavy metal circulation within the canopy but also offer further insights for mitigating urban heavy metal pollution. Most heavy metals have been enriched when passing through the urban forest canopy. The total heavy metal flux increased to 1.7 times of that in precipitation. One ha of urban forest can purify heavy metal deposition from 2.5 ha of urban land.

Mixed planting of fir and broadleaf trees is an effective management method for improving the productivity. We investigated soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) contents, along with their stoichiometric ratios across 10 different combinations of Chinese fir and broadleaf species (Mytilaria laosensis, Michelia macclurei, Michelia maudiae, Cinnamomum porrectum, Castanopsis hystrix, Cinnamomum burmanni, Liquidambar formosana, Michelia chapensis, Schima superba, and Michelia odora, respectively) with the stand age of 20 yr. Additionally, we examined the activities and stoichiometric characteristics of various enzymes: β-1,4-glucosidase, β-xylosidase, cellobiohydrolase, β-1,4-N-acetylaminoglucosidase, leucine aminopeptidase, and acid phosphatase to analyze nutrient limitation status in different mixed stands. The results showed that: 1) In the 0-10 cm and 10-30 cm soil layers, the highest SOC and TN contents were found in M. macclurei, whereas in the 30-50 cm soil layer, the highest contents were observed in S. superba. The highest TP content across all three soil layers was recorded in C. burmanni. Soil SOC and TN contents of the 10 forest stands decreased with the soil depth, while TP was not affected by the soil depth. 2) The measured ranges across the 10 stand types were 4.82-32.69 g·kg-1 for SOC, 0.50-2.16 g·kg-1 for TN, and 0.24-0.55 g·kg-1 for TP, indicating nutrient deficiency. Only the stands of M. macclurei and S. superba reached national average levels for SOC and TN, while the TP content of all forest stands was below the national average. 3) The results of the enzyme quantification vector model indicated that soil microbial metabolism was jointly limited by nitrogen and phosphorus. 4) Redundancy analysis revealed that TN, available phosphorus (AP), ammonium (NH4+-N), soil water content (SWC), pH, and TP were the primary factors influencing enzyme activities. Additionally, pH, AP, TP, SWC, and the carbon-to-phosphorus (C:P) ratio emerged as key determinants of enzymatic stoichiometry. In summary, M. macclurei and S. superba were effective in promoting soil nutrient levels in mixed forests of fir and broadleaf trees, being the optimal tree species for the mixed forest renovation in the South subtropical region. Given the prevalent limitations of nitrogen and phosphorus, external nitrogen and phosphorus inputs should be considered in future management practices.

Excessive copper can harm biodiversity and affect human health. Therefore, the remediation of copper tailings has become an urgent problem that must be solved. This study investigates the remediation effects of utilizing organic biological fertilizers and biological agents in conjunction with Broussonetia papyrifera restoration on copper tailings, as well as their impact on promoting B. papyrifera growth. This experiment conducted a quantitative analysis of copper tailings properties and copper components, examined the structure and stability of the bacterial community, and evaluated their influence on B. papyrifera growth. This study found that bioorganic fertilizer and biological agents could increase ammonium nitrogen content, improve the copper tailings quality index, and reduce residual copper content. The bioorganic fertilizer and biological agent treatment changed the copper tailings bacteria community structure, among which Thermodesulfovibrionia and Clostridioides were the core taxa. Although biological agents reduced the richness and diversity of the bacterial community, they were more beneficial to the stability of the bacteria community. Among copper tailings properties, pH was most closely related to the bacteria community. Bioorganic fertilizers and biological agents were found to increase the abundance of copper resistance genes, enhance fermentation function. Additionally, biological agents and organic biological fertilizers significantly boosted the B. papyrifera biomass by 122.59-329.40 % and increased the copper content in plants by 34.15-48.95 %. This study offers novel insights and a theoretical foundation for the future management of copper tailings.

Glyphosate pollution and greenhouse gas emissions are major problem in achieving sustainable soil management. It is necessary to develop effective strategies to simultaneously reduce herbicide residues and nitrous oxide (N2O) emissions in soil. This study aimed to: (1) quantitative analyze the effects of nitrogen (N) cycle inhibitors (nitrification inhibitors 3,4 dimethylpyrazole phosphate (DMPP) and dicyandiamide (DCD) and urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT)) on glyphosate degradation and reduction of N2O under different soil moistures; (2) identify the functional microbes and genes associated with glyphosate degradation and N2O emissions; and (3) decipher the main mechanisms of N cycle inhibitors affecting glyphosate degradation at different soil water contents. Compared to the control, the application of DMPP, DCD and NBPT reduced glyphosate residues in soil by 33.0 %, 60.3 % and 35.7 %, respectively, under 90 % water holding capacity (WHC). The application of DCD stimulated Acidobacteria and the phnX gene to degrade soil glyphosate. Further, soil glyphosate residues were significantly and negatively related to soil N2O emissions at both 60 % and 90 % WHC. Compared to the control, NBPT application decreased cumulative N2O emissions by 91.4 % at 90 % WHC by decreasing soil nitrate N (NO3- -N) and inhibiting amoC and narG genes at 90 %. The application of N cycle inhibitors could be a potential strategy to simultaneously reduce glyphosate residues and soil N2O emissions. Our study could provide technical support to reduce the risks of herbicide exposure and reduce greenhouse gas emissions.

The role of manganese (Mn) in ecosystem carbon (C) biogeochemical cycling is gaining increasing attention. While soil Mn is mainly derived from bedrock, atmospheric deposition could be a major source of Mn to surface soils, with implications for soil C cycling. However, quantification of the atmospheric Mn cycle, which comprises emissions from natural (desert dust, sea salts, volcanoes, primary biogenic particles, and wildfires) and anthropogenic sources (e.g., industrialization and land-use change due to agriculture), transport, and deposition, remains uncertain. Here, we use compiled emission data sets for each identified source to model and quantify the atmospheric Mn cycle by combining an atmospheric model and in situ atmospheric concentration measurements. We estimated global emissions of atmospheric Mn in aerosols (<10 mu m in aerodynamic diameter) to be 1,400 Gg Mn year(-1). Approximately 31% of the emissions come from anthropogenic sources. Deposition of the anthropogenic Mn shortened Mn "pseudo" turnover times in 1-m-thick surface soils (ranging from 1,000 to over 10,000,000 years) by 1-2 orders of magnitude in industrialized regions. Such anthropogenic Mn inputs boosted the Mn-to-N ratio of the atmospheric deposition in non-desert dominated regions (between 5 x 10(-5) and 0.02) across industrialized areas, but that was still lower than soil Mn-to-N ratio by 1-3 orders of magnitude. Correlation analysis revealed a negative relationship between Mn deposition and topsoil C density across temperate and (sub)tropical forests, consisting with atmospheric Mn deposition enhancing carbon respiration as seen in in situ biogeochemical studies.

The quantification of large-scale leaf-age-dependent leaf area index has been lacking in tropical and subtropical evergreen broadleaved forests (TEFs), despite the recognized importance of leaf age in influencing leaf photosynthetic capacity in this biome. Here, we simplified the canopy leaves of TEFs into three age cohorts (i.e., young, mature, and old, with different photosynthesis capacities; i.e., Vc,max) and proposed a novel neighbor-based approach to develop the first gridded dataset of a monthly leaf-age-dependent leaf area index (LAI) product (referred to as Lad-LAI) at 0.25∘ spatial resolution over the continental scale during 2001–2018 from satellite observations of sun-induced chlorophyll fluorescence (SIF) that was reconstructed from MODIS and TROPOMI (the TROPOspheric Monitoring Instrument). The new Lad-LAI products show good performance in capturing the seasonality of three LAI cohorts, i.e., young (LAIyoung; the Pearson correlation coefficient of R=0.36), mature (LAImature; R=0.77), and old (LAIold; R=0.59) leaves at eight camera-based observation sites (four in South America, three in subtropical Asia, and one in the Democratic Republic of the Congo (DRC)) and can also represent their interannual dynamics, validated only at the Barro Colorado site, with R being equal to 0.54, 0.64, and 0.49 for LAIyoung, LAImature, and LAIold, respectively. Additionally, the abrupt drops in LAIold are mostly consistent with the seasonal litterfall peaks at 53 in situ measurements across the whole tropical region (R=0.82). The LAI seasonality of young and mature leaves also agrees well with the seasonal dynamics of the enhanced vegetation index (EVI; R=0.61), which is a proxy for photosynthetically effective leaves. Spatially, the gridded Lad-LAI data capture a dry-season green-up of canopy leaves across the wet Amazonian areas, where mean annual precipitation exceeds 2000 mm yr−1, consistent with previous satellite-based analyses. The spatial patterns clustered from the three LAI cohorts also coincide with those clustered from climatic variables over the whole TEF region. Herein, we provide the average seasonality of three LAI cohorts as the main dataset and their time series as a supplementary dataset. These Lad-LAI products are available at https://doi.org/10.6084/m9.figshare.21700955.v4 (Yang et al., 2022).

Manganese (Mn) is a key cofactor in enzymes responsible for lignin decay (mainly Mn peroxidase), regulating the rate of litter degradation and carbon (C) turnover in temperate and boreal forest biomes.While soil Mn is mainly derived from bedrock, atmospheric Mn could also contribute to soil Mn cycling, especially within the surficial horizon, with implications for soil C cycling. However, quantification of the atmospheric Mn cycle, which comprises emissions from natural (desert dust, sea salts, volcanoes, primary biogenic particles, and wildfires) and anthropogenic sources (e.g. industrialization and land-use change due to agriculture) transport, and deposition into the terrestrial and marine ecosystem, remains uncertain. Here, we use compiled emission datasets for each identified source to model and quantify the atmospheric Mn cycle with observational constraints. We estimated global emissions of atmospheric Mn in aerosols (<10 µm in aerodynamic diameter) to be 1500 Gg Mn yr-1. Approximately 32% of the emissions come from anthropogenic sources. Deposition of the anthropogenic Mn shortened soil Mn “pseudo” turnover times in surficial soils about 1-m depth (ranging from 1,000 to over 10,000,000 years) by 1-2 orders of magnitude in industrialized regions. Such anthropogenic Mn inputs boosted the Mn-to-N ratio of the atmospheric deposition in non-desert dominated regions (between 5×10-5 and 0.02) across industrialized areas, but still lower than soil Mn-to-N ratio by 1-3 orders of magnitude. Correlation analysis revealed a negative relationship between Mn deposition and topsoil C density across temperate and (sub)tropical forests, illuminating the role of Mn deposition in these ecosystems.

以广州主要城市公园鸟类群落为研究对象,从中国观鸟记录中心获取 2017-2021 年间广州市主要城市公园的鸟类观测数据,采用单因素方差分析、聚类分析、相关性分析和冗余分析探究干扰强度和斑块结构对鸟类群落的影响,揭示影响城市公园鸟类群落组成和物种丰富度的主要环境因子,研究结果如下:(1)广州主要城市公园共有鸟类 243 种,隶属于 19 目 58 科.(2)高干扰强度下鸟类丰富度显著高于低强度(P<0.05),低干扰强度下Pielou均匀度指数显著高于中干扰强度和高干扰强度(P<0.05),但Shannon多样性指数无显著差异.(3)鸟类丰富度和Shannon多样性指数与公园面积、水域斑块数呈正相关,与绿地破碎度和周长面积比(PAR)呈负相关.鸟类食性集团和取食集团的分布不仅受到绿地斑块数和水域斑块数的正向影响,还受到绿地破碎度、水域破碎度和建筑面积占比率的负面影响.研究结果表明,不同的干扰强度和斑块结构均会对城市公园鸟类群落造成显著影响,在建设城市公园时应综合考虑公园的面积、形状、水域占比率、水域斑块数和绿地斑块数,丰富公园的生境异质性.

为了解帽峰山森林公园鸟类多样性及其群落结构特征,于2020年11月到2022年3月,采用样线法结合红外相机法,逐月对帽峰山森林公园鸟类进行调查.结果表明:1)共记录鸟类16目46科143种;18种鸟类属国家二级重点保护动物,8种属CITES附录Ⅱ保护动物;优势种为红耳鹎(Pycnonotus jocosus)、白喉红臀鹎(Pycnonotus aurigaster)、淡眉雀鹛(Alcippe morrisonia)和暗绿绣眼鸟(Zosterops simplex)4种;鸟类居留型中留鸟占绝大部分(90种),区系中以东洋界占优势(80种);生态类型以林鸟(132种)为主,食性上以食虫(67种)和杂食性(46种)鸟类为主,具有明显的森林鸟类群落特征.2)生境中Shannon-Wiener多样性指数、Simpson优势度指数和Margalef丰富度指数均表现为林地最高,公路最低,各生境的Pielou均匀度指数相近;季节中Shannon-Wiener多样性指数和Margalef丰富度指数表现为春季最高,夏季最低;四季Pielou均匀度指数与Simpson优势度指数均相近;3)鸟类多样性与生境类型、季节有明显相关性(P＜0.05).总体上,帽峰山森林公园生境多样,鸟类资源丰富,鸟类群落结构较稳定且具有较高的鸟类多样性.

improvements in providing high spatial and temporal resolution SIF observations, but the short temporal coverage of the data records has limited its applications in long-term studies (Veefkind et al., 2012).RTSIF uses machine learning to reconstruct TROPOMI SIF for 2001-2020 with a spatial resolution of 0.05° and a temporal resolution of 8 days.We resample temporal resolution as monthly.Tair and SW can be obtained directly from the relevant website.All of datasets used in this study are list in Table S3.The air temperature (Tair) grid files are available at website: https://rda.ucar.edu/datasets/ds314.3/.

Air quality issues caused by PM2.5-induced persistent extreme haze episodes have become increasingly serious in urban environments in recent years. Secondary water-soluble inorganic sulfate (SO42-), nitrate (NO3-) and ammonium (NH4+) ions are the major components of PM2.5. However, the contributions of inorganic nitrogen species, especially nitrate, to PM2.5 have greatly increased during haze episodes in many cities in China. Therefore, better understanding of their emission sources and formation pathways holds the key to controlling urban PM2.5 pollution more efficiently and effectively. In this study, water-soluble ionic characteristics and isotopic compositions and sources of NH4+ and NO3-, as well as NO3- formation pathways were determined in PM2.5 aerosol samples collected in Guangzhou, China, during 2015-2018. The PM2.5 concentrations varied from 30.5 to 189.8 mu g.m(-3) and their mean values were highest in spring (111.1 mu g.m(-3)) and lowest in summer (63.5 mu g.m(-3)). The delta N-15-NH4+ and delta N-15-NO3- values ranged from +4.5 to +20.2 parts per thousand and from +4.8 to +14.8 parts per thousand, respectively, with their mean values being highest in winter (14.0 parts per thousand and 9.5 parts per thousand, respectively) and lowest in summer (10.4 parts per thousand and 7.1 parts per thousand, respectively). The seasonal delta N-15 variability was mainly attributed to isotopic equilibrium fractionation, and partly due to the changes in NH3 and NOx sources. The average delta O-18-NO3- value of 63.0%, ranging seasonally from +58.6% in summer to +68.0% in spring, suggests that NO2 +.OH pathway played a vital role (70.3-85.9 parts per thousand) in NO3- formation. The Bayesian isotope mixing model results revealed fossil fuel combustion sources as dominant sources of atmospheric NH3 and NOx. This study suggests that more effort should be devoted to reduce NH3 and NOx from combustion-related processes and highlights the importance of delta O-18-NO3- analysis for exploring variations of nitrate formation pathways in urban atmospheres.

Manganese (Mn) is a key cofactor in enzymes responsible for lignin decay (mainly Mn peroxidase), regulating the rate of litter degradation and carbon (C) turnover in temperate and boreal forest biomes.While soil Mn is mainly derived from bedrock, atmospheric Mn could also contribute to soil Mn cycling, especially within the surficial horizon, with implications for soil C cycling. However, quantification of the atmospheric Mn cycle, which comprises emissions from natural (desert dust, sea salts, volcanoes, primary biogenic particles, and wildfires) and anthropogenic sources (e.g. industrialization and land-use change due to agriculture) transport, and deposition into the terrestrial and marine ecosystem, remains uncertain. Here, we use compiled emission datasets for each identified source to model and quantify the atmospheric Mn cycle with observational constraints. We estimated global emissions of atmospheric Mn in aerosols (<10 μm in aerodynamic diameter) to be 1500 Gg Mn yr-1. Approximately 32% of the emissions come from anthropogenic sources. Deposition of the anthropogenic Mn shortened soil Mn “pseudo” turnover times in surficial soils about 1-m depth (ranging from 1,000 to over 10,000,000 years) by 1-2 orders of magnitude in industrialized regions. Such anthropogenic Mn inputs boosted the Mn-to-N ratio of the atmospheric deposition in non-desert dominated regions (between 5×10-5 and 0.02) across industrialized areas, but still lower than soil Mn-to-N ratio by 1-3 orders of magnitude. Correlation analysis revealed a negative relationship between Mn deposition and topsoil C density across temperate and (sub)tropical forests, illuminating the role of Mn deposition in these ecosystems. Hosted file 973441_0_art_file_11362392_s0nb47.docx available at https://authorea.com/users/661368/ articles/664495-characterizing-the-atmospheric-mn-cycle-and-its-impact-on-terrestrialbiogeochemistry Hosted file 973441_0_supp_11362393_s0nb47.docx available at https://authorea.com/users/661368/ articles/664495-characterizing-the-atmospheric-mn-cycle-and-its-impact-on-terrestrialbiogeochemistry

Urbanization is increasing worldwide, which have considerable consequences on ecosystem functions such as soil carbon (C) sequestration, however, the underlying microbial mechanisms regulated by plant diversity of urbanization on forest soil organic C stocks (SOCs) is still unclear. In this study, plant diversity along an urban-suburban-rural gradient and its relationships with the activities of micro-enzymes and the SOCs were quantified. We found that urbanization significantly reduced SOCs in surface soils via changing temperature, soil C: P ratios, and the relative abundance of key enzymes for C sequestration and degradation. Plant diversity showed significant and positive effects on SOCs via affecting soil C: P ratios and microorganisms. The greater effects of plant diversity than those of urbanization on SOCs imply that plant diversity can mitigate the negative effects on soil C sequestration in the context of global warming, which provides a sound theoretical basis for effectively improving forest quality and ecological functions.

[目的]为摸清广东大瑶山省级自然保护区物种本底资料,转变目前该保护区鸟兽多样性研究相对滞后的局面.[方法]于2020-2022年,在大瑶山自然保护区以1km×2km的公里网格法,布设了49台红外相机,对保护区内林下鸟兽多样性进行了调查.[结果]1)累计21505个有效相机工作日,共获得独立有效照片9113张;拍摄到59种野生动物,其中鸟类45种(隶属于8目19科)、兽类14种(隶属于3目9科).2)在59种野生动物中,国家一级重点保护野生动物有1种,即黄腹角雉(Tragopan caboti);国家二级重点保护野生动物有白鹇(Lophura nycthemera)、仙八色鸫(Pitta nympha)、豹猫(Prionailurus bengalensis)等12种;IUCN红色名录易危(VU)物种2种;中国脊椎动物红色名录濒危(EN)物种1种,易危(VU)5种,近危(NT)10种;CITES附录Ⅰ和附录Ⅱ收录分别有2种和9种.3)相对多度指数较高的鸟类依次是:白鹇(15.92)、紫啸鸫(Myophonus caeruleus,1.81)、灰胸竹鸡(Bambusicola thoracicus,0.71)、虎斑地鸫(Zoothera aurea,0.39)和黑领噪鹛(Garrulaxpectoralis,0.27);兽类依次是:赤麂(Muntiacus vaginalis,9.62)、鼬獾(Melogale moschata,5.24)、小麂(Muntiacus reevesi,1.99)、赤腹松鼠(Callosciurus erythraeus,1.67)、红腿长吻松鼠(Dremomys pyrrhomerus,1.30).4)春季鸟类有效照片数和独立有效照片数最多;夏季鸟类丰富度和Shannon-Wiener多样性指数最低;冬季鸟类丰富度和Shannon-Wiener多样性指数最高,但独立有效照片数最少.夏季兽类独立有效照片数和Shannon-Wiener多样性指数最低;秋季兽类有效照片数和独立有效照片数最多;冬季兽类Shannon-Wiener多样性指数最高.黄腹角雉春季相对多度指数最高,冬季最低;白鹇和仙八色鸫夏季相对多度指数最高,冬季最低;豹猫秋季相对多度指数最高,夏季最低.5)广义线性混合模型结果显示:鸟类丰富度受高速公路、林分类型、地形和村庄的显著影响,鸟类丰富度在靠近高速公路、阔叶林、上坡位和村庄的区域较高;兽类丰富度受地形的显著影响,在山体中的平地和上坡位会较高.[结论]本次调查结果完善了保护区鸟类和兽类资源的时空分布信息,为大瑶山自然保护区进一步开展鸟兽多样性研究提供了基础资料,也为后续保护区的保护和管理工作提供了科学依据.

AbstractIdentifying patterns and drivers of plant community assembly has long been a central issue in ecology. Many studies have explored the above questions using a trait‐based approach; however, there are still unknowns around how patterns of plant functional traits vary with environmental gradients. In this study, the responses of individual and multivariate trait dispersions of 134 species to soil resource availability were examined based on correlational analysis and torus‐translation tests across four spatial scales in a subtropical forest, China. Results indicated that different degrees of soil resource availability had different effects on trait dispersions. Specifically, limited resource (available phosphorus) showed negative relationships with trait dispersions, non‐limited resource (available potassium) showed positive relationships with trait dispersions, and saturated resource (available nitrogen) had no effect on trait dispersions. Moreover, compared with the stem (wood density) and architectural trait (maximum height), we found that leaf functional traits can well reflect the response of plants to nutrient gradients. Lastly, the spatial scale only affected the magnitude but not the direction of the correlations between trait dispersions and environmental gradients. Overall, the results highlight the importance of soil resource availability and spatial scale in understanding how plant functional traits respond to environmental gradients.

This dataset provides 0.25 degree spatial resolution leaf age-dependent LAI seasonality product (Lad-LAI) (2001-2018) over tropical and subtropical evergreen broadleaved forests (TEFs). The mapped extent is longitude (-180, 180) and latitude (-30, 30). (1) Methodology and performance The canopy leaves of TEFs were simplified into three age cohorts, i.e., young, mature and old one, with different photosynthesis capacity (maximum carboxylation rate, Vcmax) to produce a grid dataset of leaf age-dependent LAI product (referred to as Lad-LAI) over the continental scale from satellite observations of TROPOMI sun-induced chlorophyll fluorescence (SIF) as a proxy of leaf photosynthesis. Validations against in situ measurements of seasonal LAI data, satellite based EVI and in situ measurements of seasonal litterfall data demonstrated the products were in high accuracy. (2) Dataset information The dataset is provided in geotif (*.tif) format with pixel values of 0-7 for LAIyoung, LAImature and LAIold. Data named "LAI_young_025deg_1.tif" means leaf area index of young leaves mapped in January.Any questions about the dataset can be corresponded to Xiuzhi Chen (chenxzh73@mail.sysu.edu.cn).

森林可燃物是发生森林火灾的重要物质基础,研究其特征对预研森林火灾发展规律具有重要作用.以粤北地区的5种典型森林(桉树林、马尾松林、杉木林、毛竹林和木荷林)为研究对象,测定了森林的灌木(Ⅰ)、草本(Ⅱ)、腐殖质(Ⅲ)和枯落物Ⅳ(d<0.6cm)、Ⅴ(0.6cm≤d<2.5cm)和Ⅵ(2.5cm≤d<7.62cm)的可燃性指标(干鲜比、平衡含水率、燃点和热值),分析可燃性指标间的差异及其关系,初步评价森林的可燃性.研究结果表明,可燃物的干鲜比位于41.88％～85.99％,枯落物Ⅴ最大,且不同可燃物类型间具有极显著的差异(P<0.01).5种林分类型的腐殖质层(Ⅲ)、枯落物Ⅳ、Ⅴ和Ⅵ平衡含水率变幅分别为4.77％ ～5.01％,6.86％～7.27％,8.26％～9.64％和9.94％～10.58％;枯落物的平衡含水率随直径增大而升高,枯落物Ⅵ的平衡含水率显著高于Ⅲ(P<0.01).腐殖质和枯落物的燃点分别为264.67～271.00℃和248.00～255.17℃,热值则分别达8.47～11.50kJ/g和16.11～17.92kJ/g;腐殖质的燃点显著高于枯落物(P<0.01),热值则与之相反.Person相关分析表明,所有可燃物的干鲜比之间具有正向共性,即两两之间干鲜比正相关;平衡含水率对燃点的影响大于干鲜比.5种森林的抗火性强度分成3类,第1类为木荷林,抗火性强林分,第2类是毛竹林,为抗火性中等林分,第3类包括马尾松、杉木和桉树林,为相对易燃林分.