How topography and neighbor shape the fate of trees in subtropical forest restoration:Environmental filtering and resource competition drive natural regeneration

The structure of plant communities at local scales depends on both the spatial heterogeneity of abiotic environmental factors and the biotic interactions within the community.However,although environmental filtering due to microtopographic heterogeneity and resource competition among plants caused by spatial variation in tree density and size are considered to be very important in explaining the mechanisms of community assembly,their effects on the processes of individual mortality and recruitment in natural forest regeneration,as well as their relative contributions,are still poorly understood.To address this,we established a 12-ha permanent plot in a subtropical evergreen broad-leaved forest area and measured microtopographic variables such as elevation,slope,aspect,and terrain position index(TPI)using a total station.We monitored the individual mortality and recruitment in forest natural regeneration through repeated surveys at 5-year intervals.We fitted spatial covariance models to jointly use multiple factors from three groups of variables(microtopographic effect,neighborhood density effects,neighborhood size effects)as explanatory variables to analyze their roles in driving the mortality and recruitment of all individual and 12 dominant species in forest natural regeneration at the neighborhood scale.Our results show that:(1)In the crucial early stages of secondary forest restoration,natural regeneration is influenced by a synergy of environmental filtering,due to microtopographic heterogeneity,and resource competition among plants.(2)For distinct species responses,evergreen dominant species'mortality is largely explained by neighborhood effects,while deciduous species are more affected by topographic factors.Furthermore,the adverse effects of larger conspecific trees on younger trees indicate a pattern of competitive pressure leading to mortality among regenerating trees,such pattern emphasis the influence of parent trees on natural regeneration.(3)As trees grow,their interaction with these stressors evolves,suggesting a shift in their resource acquisition strategies and response to neighborhood effects and environmental factors.Despite these changes,the relative importance of topographic factors in determining survival and recruitment success remains constant.This research highlights the importance of considering both environmental and neighborhood effects in forest management,particularly in early secondary forest restoration.

A Comparative Analysis of Environmental Quality Assessment Methods for Heavy Metal-Contaminated Soils

Four assessment methods （two pollution indexes and two fuzzy mathematical models） were employed to investigate the environmental quality of four soils around a ferroalloy plant in Nanjing City. Environmental quality was assessed as class Ⅳ （moderately polluted） for each soil with single-factor index method, and was identified to be classes Ⅳ, Ⅲ （slightly polluted）, Ⅲ, and Ⅲ for soils A, B, C, and D, respectively, with the comprehensive index model. In comparison with the single-factor index method, the comprehensive index model concerned both dominant parameter and average contribution of all factors to the integrated environmental quality. Using the two fuzzy mathematical methods （single-factor deciding and weighted average models）, the environmental risks were determined to be classes Ⅳ, Ⅲ, Ⅱ （clean）, and Ⅱ for soils A, B, C, and D, respectively. However, divergence of the membership degree to each pollution class still occurred between the two methods. In fuzzy mathematical methods, membership functions were used to describe the limits between different pollution degrees, and different weights were allocated for the factors according to pollution contribution. Introduction of membership degree and weight of each factor to fuzzy mathematical models made the methods more reasonable in the field of environmental risk assessment.

Environmental Geochemistry of Heavy Metal Contaminants in Soil and Stream Sediment in Panzhihua Mining and Smelting Area,Southwestern China

Mining and smelting activities are the main causes for the in creasing pollution of heavy metals in soil, water body and stream sediment. An e nvironmental geochemical investigation was carried out in and around the Panzhih ua mining and smelting area to determine the extent of chemical contamination in soil and sediment. The main objective of this study was to investigate the envi ronmental geochemistry of Ti, V, Cr, Mn, Cu, Pb, Zn and As in soil and sediment and to assess the degree of pollution in the study area. The data of heavy metal concentrations reveal that soils and sediments in the area have been slightly c ontaminated. Geochemical maps of I\-\{geo\} of each heavy metal show that the co ntaminated sites are located in V-Ti-magnetite sloping and smelting, gangues d am. The pollution sources of the selected elements come mainly from dusts result ant from mining activities and other three-waste-effluents. The area needs to be monitored regularly for trace metal, especially heavy metal enrichment.

Effects of Environmental Lead Pollution on Blood Lead and Sex Hormone Levels among Occupationally Exposed Group in An E-waste Dismantling Area

Objective To study the effects of environmental multi-media lead pollution on blood lead and sex hormone levels among lead exposed males engaged in E-waste dismantling, and the correlation between confounding factors and sex hormone levels. Methods An E-waste dismantling area in Taizhou of Zhejiang Province was selected as the research site. One hundred and fifty two samples were collected from the groundwater, soil, rice, corn, chicken, and pork in the dismantling area. The effects of the multi-media lead pollution on the male blood lead and sex hormone levels of FSH, LH, and T, as well as the correlation with confounding factors, were studied. Results The blood lead concentrations in the males aged under 31, from 31 to 45 and from 46 to 60 were 98.55, 100.23, and 101.45 I~/L, respectively. Of all the environmental media lead exposures, the groundwater, rice and soil were main contributing factors to the lead accumulation in humans. FSH and LH levels increased with the age while the T levels decreased with the age instead. There was a significant correlation between the FSH and LH levels and wearing masks. Conclusion There was correlation between the FSH, LH, and T levels, and the mean values of lead concentrations in environmental media, and the sex hormone levels were correlated with the confounding factor of wearing masks.

Study on the Post-evaluation of Environmental Planning Based on Logical Framework Approach

[Objective] The aim was to conduct post-evaluation on environmental planning by means of logical framework approach. [Method] Taking environmental planning during '11th Five-year Plan' in a certain province for example, by means of logical framework approach (LFA), the post-evaluation on environmental planning was carried out from the aspects of evaluation content, index system, implementation steps, evaluation feedback and input-output analysis of environmental planning. [Result] The post-evaluation on environmental planning by means of LFA achieved expected purpose and various indexes at different stages of environmental planning was assessed, and then corresponding countermeasures were put forward according to the problems which were found by problem tree of environmental planning project. [Conclusion] The study could provide theoretical references for the post-evaluation on environmental planning in future.

Integrated water risk early warning framework of the semi-arid transitional zone based on the water environmental carrying capacity (WECC)

Water risk early warning systems based on the water environmental carrying capacity(WECC)are powerful and effective tools to guarantee the sustainability of rivers.Existing work on the early warning of WECC has mainly concerned the comprehensive evaluation of the status quo and lacked a quantitative prejudgement and warning of future overload.In addition,existing quantitative methods for short-term early warning have rarely focused on the integrated change trends of the early warning indicators.Given the periodicity of the socioeconomic system,however,the water environmental system also follows a trend of cyclical fluctuations.Thus,it is meaningful to monitor and use this periodicity for the early warning of the WECC.In this study,we first adopted and improved the prosperity index method to develop an integrated water risk early warning framework.We also constructed a forecast model to qualitatively and quantitatively prejudge and warn about the development trends of the water environmental system.We selected the North Canal Basin(an essential connection among the Beijing-Tianjin-Hebei region)in China as a case study and predicted the WECC in 25 water environmental management units of the basin in 2018–2023.We found that the analysis of the prosperity index was helpful in predicting the WECC,to some extent.The result demonstrated that the early warning system provided reliable prediction(root mean square error of 0.0651 and mean absolute error of 0.1418),and the calculation results of the comprehensive early warning index(CEWI)conformed to the actual situation and related research in the river basin.From 2008 to 2023,the WECC of most water environmental management units in the basin had improved but with some spatial differences:the CEWI was generally poor in areas with many human disturbances,while it was relatively good in the upstream regions with higher forest and grass covers as well as in the downstream areas with larger water volume.Finally,through a sensitivity analysis of the indicators,we proposed specific management measures for the sustainability of the water environmental system in the North Canal Basin.Overall,the integrated water risk early warning framework could provide an appropriate method for the water environmental administration department to predict the WECC of the basin in the future.This framework could also assist in implementing corresponding management measures in advance,especially for the performance evaluation and the arrangement of key short-term tasks in the River Chief System in China.

Optical Characteristics of Chromophoric Dissolved Organic Matter(CDOM)in Upstream and Downstream Lakes of Taihu Lake Basin:New Insights for Water Environmental Management

Chromophoric dissolved organic matter(CDOM)is a key component of organic matter that contributes to the ecological functioning of lakes.The lakes in Taihu Lake Basin play an important role in maintaining regional ecological stabilities;however,the optical characteristics of the CDOM in the upstream and downstream lakes in this basin have not yet been systematically studied.Here,the optical characteristics of CDOM in ten lakes of upstream and downstream of the Taihu Lake Basin were studied using UV-Visible and excitation-emission matrix spectroscopies.Three different fluorophores consisting of two humic-like components(C1,C2)and one protein-like component(C3)were identified by parallel factor analysis.Soil or surface erosion was responsible for the higher abund-ance of C1 in the upstream lakes,and increased biological activities accounted for the higher abundance of C3 in the downstream lakes.Rainfall erosion in the wet season led to an increase in CDOM.We also found that the photodegradation and flocculation degree,which played a significant role in reducing CDOM,were higher in downstream lakes than in upstream lakes.Optical analysis of CDOM provides a promising method for monitoring water qualities(e.g.,total phosphorus and potassium permanganate index)in each lake.Re-ductions in soil or surface erosion in the upstream are needed to improve water quality.

New Normal of Environmental Protection: Our Responsibility and Action

It has become the hot topic of new normal for environmental protection to ＂ impel ecological civilization and create new way of environ- mental protection＂. In this paper, based on current severe environmental protection situation, new idea of ＂government taking the stage, research department writing a play,enterprise acting in an opera and the masses supervising＂ and action plan of ＂government having the right but can not be impulsive, research department having the talent and should discharge their duties, enterprise having the money but should keep law, and the mas- ses having the enthusiasm to strengthen supervision＂ for environmental protection are proposed,which aims to contribute ideas and exert efforts for impelling ecological civilization and environmental protection.

Tendency and Control Strategy of Agricultural Environmental Pollution in China

Current situation of China＇s agricultural pollution was elaborated, and the causes of the pollution were analyzed. Moreover, China＇s agri- cultural pollution tendency in the next few years was predicted. In order to control agricultural pollution in China, we should construct a diet structure for health and ecological civilization and create an ecological food chain by establishing a new concept of diet.

Research on Environmental Impact Assessment Methods of Farmland Improvement along Coastal Areas of Jiangsu Province

[ Objective] The study aimed to assess the impact of farmland improvement on ecological environment along coastal areas of Jiangsu Province. [ Method] Taking the coastal farmland improvement of Sheyang County, Jiangsu Province as an example, an indicator system of environ- mental impact assessment （EIA） for coastal farmland improvement was established based on data collection, field survey and monitoring results, expert consultation, literature study and other methods, including four subsystems （biological resource, soil, vegetation and water environment） and 12 indicators. [ Result] The weights of soil, biological resource, vegetation and water environment were 0.614, 0.219, 0.118 and 0.049, and the top weight of soil showed that farmland improvement had a great influence on soil. Among the 12 indicators, the most important indicators with higher weights were reclamation rate of the land （weight 0.389）, population density （weight 0.164） and the content of soil organic matter （weight 0.088）. Therefore, in EIA of such kind of projects in the future, we should give prominence to the identification, evaluation and monitoring of the main characteristic factor above. [ Conclusion] The research could provide scientific references for the sustainable utilization of resources and estab- lishment of environmental management policies along costal areas of Jiangsu Province.

Holocene environmental change according to lake core in Fildes Peninsula of King George Island,Antarctica

Lake core sampled from Xihu in Fildes Peninsula of King Gorge Island, Antarctica could reveal the environmental change of the district. The lake core( GA7) , 9.28 meters long , was sectioned at an interval of 2 cm. Through measuring the organic carbon, magnetic susceptibility, granularity and organic carbon isotope of GA7, by use of 14C age it was estimated that there were four periods of high temperature in Fildes Peninsula; 4800-4400 aB. P. , 3600-3350 aB. P. ,2100 - 1800 aB. P. and 900 aB. P. - present. Meanwhile, results showed that there was a strikingly positive correlation between the content of organic carbon and that of organic carbon isotope (δC01213 ) which could be the substitute indicators of environmental temperature.

The progress of strategic environmental assessment （SEA）： Studies and practices in the mainland, Hong Kong and Taiwan of China

Strategic environmental assessment （SEA） is the process to evaluate, in a systematic way, the possible environmental impacts caused by decision making such as policy, plan, and program. It is of highly significance to improve decision-making. This article reviewed the researches on SEA as well as its practices in Taiwan, Hong Kong and the mainland of China. The regulations, methodologies, and effect of practices were compared. The regulations on SEA had been enacted at three places respectively. With the largest spatial area and rapid economic development pace, the mainland has carded out more SEA practices recently than the other two places, but their final effect still need to be confirmed. It was said that Hong Kong had acquired considerable experiences on SEA, while practice of SEA at Taiwan lagged behind.

Epiphytic zooplankton community profiles in a typical urban wetland as revealed by DNA metabarcoding

Zooplankton,a crucial component of urban wetland,are one of the effective bioindicators for monitoring the feeding stocks of organisms at higher trophic levels and assessing the ecological quality of ecosystems.However,information about the characteristics of epiphytic zooplankton community structure resulted from traditional methods is limited and hindered by the large amount of detritus and sludge attached to the macrophytes.We investigated the epiphytic zooplankton communities associated with macrophytes(Vallisneria,Nymphaea,and Thalia dealbata)in a subtropical wetland using as DNA markers of the 18 S rRNA gene and the mitochondrial cytochrome c oxidase subunit I(COI)gene.A total of 241 OTUs of zooplankton were obtained from COI amplicons,including 194 OTUs of Rotifera,22 of Cladocera,and 25 of Copepoda,while only 62 OTUs of zooplankton were obtained from 18 S rDNA amplicons including 34 OTUs of Rotifera and 28 of Copepoda.The zooplankton communities associated with the three macrophytes were similar,but they differed significantly from those in the open waters.However,there were no significant temporal differences among the zooplankton communities.Epiphytic zooplankton communities were dominated by littoral zooplankton such as Testudinella,Lecane,and Philodina.Microzooplankton,especially littoral species,utilize macrophytes as food sources and as refuges against predation.This further led to an increase inαandβdiversity of zooplankton communities in urban wetlands.Our result suggests that the joint use of multiple molecular markers could improve the taxonomic resolution and generate a comprehensive biodiversity profile of zooplankton.

Effects of Dietary Changes on the Gut Microbiota of Cynops orientalis

The gut microbiota plays a pivotal role in the maintenance of health for amphibians,and it has been fully recognized,but the effectiveness of various influencing factors has not yet been fully clarified.Although this association should be considered while the amphibian order Caudata is facing a severe situation of population decline and extinction,there is little understanding of the association between diets and the diversity of gut microbiota in the amphibian order Caudata.Here,we conducted an extensive analysis of the gut microbiota of Cynops orientalis fed different diets using functional prediction and 16S rRNA amplicon sequencing techniques.First,we found that wild individuals had greater gut microbial diversity and richness in comparison to captive individuals.Second,we identified the bacterial taxa associated with diets and observed differences in the relative abundance of gut microbiota among people on various diets.Finally,we have a predictive comprehension of the selection and adaptative significance of shared core ASVs in the gut microbiota in maintaining the healthy survival of C.orientalis in a large-scale spatiotemporal map.Our study emphasizes how diets alter the gut microbiota of Caudata and offers fresh perspectives on the conservation and captive management of species in Caudata.

Impacts of Comorbidity and Mental Shock on Organic Micropollutants in Surface Water During and After the First Wave of COVID-19 Pandemic in Wuhan (2019–2021), China

The first pandemic wave of coronavirus disease 2019(COVID-19)induced a considerable increase in several antivirals and antibiotics in surface water.The common symptoms of COVID-19 are viral and bacterial infections,while comorbidities(e.g.,hypertension and diabetes)and mental shock(e.g.,insomnia and anxiety)are nonnegligible.Nevertheless,little is known about the long-term impacts of comorbidities and mental shock on organic micropollutants(OMPs)in surface waters.Herein,we monitored 114 OMPs in surface water and wastewater treatment plants(WWTPs)in Wuhan,China,between 2019 and 2021.The pandemic-induced OMP pollution in surface water was confirmed by significant increases in 26 OMP concentrations.Significant increases in four antihypertensives and one diabetic drug suggest that the treatment of comorbidities may induce OMP pollution.Notably,cotinine(a metabolite of nicotine)increased 155 times to 187 ngL1,which might be associated with increased smoking.Additionally,the increases in zolpidem and sulpiride might be the result of worsened insomnia and depression.Hence,it is reasonable to note that mental-health protecting drugs/behavior also contributed to OMP pollution.Among the observed OMPs,telmisartan,lopinavir,and ritonavir were associated with significantly higher ecological risks because of their limited WWTP-removal rate and high ecotoxicity.This study provides new insights into the effects of comorbidities and mental shock on OMPs in surface water during a pandemic and highlights the need to monitor the fate of related pharmaceuticals in the aquatic environment and to improve their removal efficiencies in WWTPs。

Decoupling REDD+ understanding of local stakeholders on the onset of materializing carbon credits from forests in Nepal

REDD+1is an economic incentivizing mechanism aimed at reducing or offsetting of carbon emissions in forests,while realizing multiple benefits alongside climate action. Engaging local stakeholders is crucial for its sustainable implementation and benefit-sharing mechanism. This study focuses on the knowledge and understanding of locallevel stakeholders about REDD+and its associated attributes, revealing significant knowledge gaps between areas with and without REDD+pilot activities. For this, we conducted the semi-structured questionnaire interviews(n=136), key informant interviews(n=27), and focus group discussions(n=4) with local-level REDD+stakeholders(LLRS) comprising both inside and outside of pilot project districts in three provinces of Nepal, by adopting the concept of socio-ecological systems(SES). Data were analyzed using a generalized linear model(GLM) and visualized through Sankey diagrams. The results indicate a poor understanding(29%) of LLRS on the REDD+process, its relationship with forests, concerns among stakeholders, and its potential significance. The perception of REDD+knowledge, mechanisms, and benefits significantly(p < 0.05) varied across study areas, age groups, genders, professional backgrounds, educational levels, ownership of private forests, and types of household energy sources used among respondents. Despite receiving readiness funds, stakeholders' comprehension of the REDD+process remains limited, indicating suboptimal policy implementation. Knowledge gaps were influenced by social background, voices and choices, and the fear of REDD+disrupting traditional practices among the LLRS. The study emphasizes the need to redress the concerns of LLRS by considering their social backgrounds and traditional practices through informed and participatory decision-making, enhance communication, transparency,and inclusive forest governance. The findings show that current external support has not sufficiently enhanced capacity among LLRS, suggesting the need for sufficient and sustainable support through national policy and financing mechanisms. Further, the study identified extremely poor REDD+-related knowledge dissemination within communities, exacerbating challenges in implementation and benefit-sharing mechanisms, revealing the simplification of its process is essential. The study advocates for revising REDD+-related policies to optimize benefits, ensure smooth implementation, realize fair and equitable carbon credits from forests, and foster shared responsibility and ownership among all stakeholders in climate actions through improved forest governance.

Bark biomass and nutrient concentrations in tropical secondary forest trees of Malaysia

Given the high-level physiological functions and nutrient concentrations of bark that cover the entire trunks of huge trees,research into bark nutrient traits and the development of models that estimate the bark biomass of tropical trees is essential when it is sought to understand forest nutrient cycling and tree ecological traits.This study investigated the concentrations of six bark nutrients(nitrogen(N),phosphorus(P),potassium(K),calcium(Ca),magnesium(Mg),and sodium(Na))by individual tree size and the soil nutrient concentrations for two major pioneer species(Macaranga gigantea and M.hosei)of Malaysia.To estimate bark biomass,allometric equations using tree diameter,height,and crown diameter were developed by combining previous data from adjacent forests with the present data.We found no significant relationship between tree size and most bark nutrient concentrations,though all nutrient concentrations of the two pioneer trees were significantly higher than those of primary forest tree species.Surprisingly,no relationship was found between the soil and bark nutrient concentrations for either species.All the size parameters used in the allometric equations accurately estimated bark biomass.There were no differences in equations between the two species when diameter served as an explanatory variable,but differences were apparent when height and crown diameter were so used.A comparison of allometric equations that yielded the bark biomasses of different types of forest showed that the bark biomass of the tropical secondary forest trees was less than half of that of tropical dry forest trees of the same diameter.Thus,the use of inappropriate equations and nutrient concentrations increases the possibility of serious errors in estimating bark biomass and forest nutrient cycles.

Extreme Precipitation Probability over East China in Spring and Summer During the Decaying of Two Types of El Niño Events

Based on the surface-gridded daily precipitation dataset and the simulation results from the Coupled Model Intercomparison Project Phase 6(CMIP6)models,this study investigates the variation of extreme precipitation probability over East China in spring and summer during the decaying year of East Pacific(EP)/Central Pacific(CP)El Niño events and explores possible influencing mechanisms.The results show that for the EP El Niño,in spring,the probability of extreme precipitation is much higher in the vast majority of East China.The anticyclonic water vapor transport in the Northwest Pacific and the higher temperature in East China jointly result in a large amount of water vapor converging and ascending in East China,which is conducive to extreme precipitation events in this region.In summer,the probability of extreme precipitation events decreases,but is still high in the Yangtze River Basin,corresponding to the weak and northerly anticyclone over the Northwest Pacific and the convergence and ascending of water vapor in the Yangtze River Basin.For the CP El Niño,the most obvious probability increase of extreme precipitation events appears over Northeast China and the Yangtze River Basin in spring.These regions are featured by positive geopotential height anomalies and strong northerly wind.Meanwhile,the temperature in Northeast China is slightly lower.In summer,the probability of extreme precipitation events in most areas significantly increases.The anomalous cold high-pressure center over the north of the South China Sea is notably strong,and the northwestern Pacific anticyclone expands to the west and the north.East China is mainly affected by the warm-wet southwesterly airflow,which is conducive to extreme precipitation events.The United States Geophysical Fluid Dynamics Laboratory model well represents the probability distribution of extreme precipitation events and the atmospheric circulation of the EP/CP El Niño.However,compared with observations,there are some biases,such as the higher probability of extreme precipitation in Central China in summer under the EP El Niño.

Application of hydrochemistry and strontium isotope for understanding the hydrochemical characteristics and genesis of strontium-rich groundwater in karst area,Gongcheng County,Southwest China

Understanding the hydrochemical characteristics and genesis mechanisms of strontium-rich groundwater is pivotal for supporting the exploitation and utilization of natural strontium-rich groundwater.In this research,27 groundwater samples were collected.By analyzing major ion chemistry and strontium isotope data,and considering the hydrogeological context,various analytical approaches,including multivariate statistics,ion ratios,and isotopes,were used to reveal the characteristics and genesis mechanisms of strontium-rich groundwater in the study area.The findings indicate that the predominant hydrochemical type of groundwater is HCO_(3)-Ca,with Ca^(2+)and HCO_(3)^(-)as the primary cations and anions.The hydrochemistry of the strontium-rich groundwater is predominantly influenced by rock weathering processes.A combination of factors,including ion exchange,and anthropogenic activities,shapes the compositional characteristics of the groundwater in the region.The dissolution of calcite due to weathering emerges as the principal source of strontium in the groundwater.While ion exchange processes are not conducive to strontium enrichment in groundwater,their effect is relatively limited.The impact of human activities on the groundwater is minor.

First flush of storm runoff pollution from an urban catchment in China

Storm runoff pollution process was investigated in an urban catchment with an area of 1.3 km^2 in Wuhan City of China. The results indicate that the pollutant concentration peaks preceded the flow peaks in all of 8 monitored storm events. The intervals between pollution peak and flow peak were shorter in the rain events with higher intensity in the initial period than those with lower intensity. The fractions of pollution load transported by the first 30% of runoff volume （FF30） were 52.2%-72.1% for total suspended solids （TSS）, 53.0%-65.3% for chemical oxygen demand （COD）, 40.4%-50.6% for total nitrogen （TN）, and 45.8%-63.2% for total phosphorus （TP）, respectively. Runoff pollution was positively related to non-raining days before the rainfall. Intercepting the first 30% of runoff volume can remove 62.4% of TSS load, 59.4% of COD load, 46.8% of TN load, and 54.1% of TP load, respectively, according to all the storm events. It is suggested that controlling the first flush is a critical measure in reduction of urban stormwater pollution.