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Model studies suggested that human-induced increase in nutrient load may have stimulated primary production and thus has enhanced the CO2 uptake capacity in the coastal ocean. In this study, we investigated the seasonal variations of the surface water's partial pressure of CO2 (pCO2sw) in the highly human-impacted Changjiang-East China Sea system between 2008 and 2011. The seasonality of pCO2sw has large spatial variations, with the largest extreme of 170±75 µatm on the inner shelf near the Changjiang Estuary (from 271±55 µatm in summer to 441±51 µatm in autumn) and the weakest extreme of 53±20 µatm on the outer shelf (from 328±9 µatm in winter to 381±18 µatm in summer). During the summer period, stronger stratification and bio-logical production driven by the eutrophic Changjiang plume results in a very low CO2 in surface waters and a very high CO2 in bottom waters on the inner shelf, with the latter returning high CO2 to the surface water during the mixed period. Interestingly, a comparison with historical data shows that the average pCO2sw on the inner shelf near the Changjiang Estuary has decreased notably during summer, but it has increased during autumn and winter from the 1990s to the 2000s. We suggest that this decadal change is associated with recently increased eutrophication. This would increase both the photosynthetic removal of CO2 in surface waters and the respiratory release of CO2 in bottom waters during summertime, thereby returning more CO2 to the surface during the subsequent mixing seasons and/or episodic extreme weather events (e.g. typhoons). Our finding demonstrates that increasing anthropogenic nutrient delivery from a large river may enhance the sequestration capacity of CO2 in summer but may reduce it in autumn and winter. Consequently, the coastal ocean may not necessarily take up more atmospheric CO2 in response to increasing eutrophication, and the net effect largely depends on the relative time scale of air-sea gas exchange and offshore transport of the shelf water. Finally, the case we reported for the Changjiang system may have general ramifications for other eutrophic coastal oceans. [ABSTRACT FROM AUTHOR]

Identifying and quantifying the sources of climate impacts from land use and land cover change (LULCC) is necessary to optimize policies regarding LULCC for climate change mitigation. These climate impacts are typically defined relative to emissions of CO2, or sometimes emissions of other long-lived greenhouse gases. Here we use previously published estimates of the radiative forcing (RF) of LULCC that include the short-lived forcing agents O3 and aerosols, in addition to long-lived greenhouse gases and land albedo change, for six projections of LULCC as a metric for quantifying climate impacts. The LULCC RF is attributed to three categories of LULCC activities: direct modifications to land cover, agriculture, and wildfire response, and sources of the forcing are ascribed to individual grid points for each sector. Results for the year 2010 show substantial positive forcings from the direct modifications and agriculture sectors, particularly from India, China, and southeast Asia, and a smaller magnitude negative forcing response from wildfires. The RF from direct modifications, mainly deforestation activities, exhibits a large range in future outcomes for the standard future scenarios implying that these activities, and not agricultural emissions (which lead to more consistent RFs between scenarios), will drive the LULCC RF in the future. We show that future forest area change can be used as a predictor of the future RF from direct modification activities, especially in the tropics, suggesting that deforestation-prevention policies that 20 value land based on its C-content may be particularly effective at mitigating climate forcing originating in the tropics from this sector. Although, the response of wildfire RF to tropical land cover changes is not as easily scalable and yet imposes a non-trivial feedback onto the total LULCC RF. [ABSTRACT FROM AUTHOR]

• Higher fertility rate induces more labor for childcare and thus crowds out labor for work. • The three-child policy slightly increases fertility intention. • The three-child policy increases emission abatement of the designed emission trading scheme. • In emission trading scheme, technological progress increases GDP and decreases total emissions. • The three-child policy strengthens technological impacts on GDP but weakens technological impacts on emissions. Although population growth plays a vital role in driving anthropogenic climate change, fertility impact on achieving mitigation target is usually overlooked in literature. This paper attempts to narrow the research gap by employing a Computable General Equilibrium (CGE) model to analyze the interrelations among fertility rate, fertility policy, and climate policy in China. The model results show that fertility rate negatively correlates with GDP and emissions because higher fertility induces more labor for childcare and thus crowds out labor for work. The three-child policy raises fertility intention; it does not unidirectionally influence the effects of the emission trading scheme (ETS) on employment and GDP, but it increases ETS emission abatement. Technological progress increases GDP and decreases emissions; the three-child policy strengthens technological impact on GDP but weakens technological impact on emissions. Hence, technological progress benefits emission mitigation; the three-child policy enhances economic benefits but impairs emission abatement of technological progress. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Agricultural greenhouse gas emission is a well-known contributor to anthropogenic climate change. It is imperative to encourage farmers to adopt low-carbon agricultural technologies (LATs). In this paper, the Delphi method was used to select nine LATs with good carbon emission reduction effects among all possible technologies adopted in the agricultural production process. Moreover, based on the survey data of 1114 farmers in Hubei province of China, we identified the potential determinants of rice farmers' decisions to adopt LATs and obtained the hierarchical structure of these determinants by employing the multivariate probit model, ordered probit model, and interpretative structural model. Results showed that there were strong complementary relationships between the nine LATs, and most rice farmers (83.48%) adopted three or fewer LATs simultaneously. It was also found that rice farmers' decisions to adopt LATs were mainly influenced by four types of factors, namely individual characteristics, family resource endowments, production managerial factors, and external environmental factors, with production managerial factors exerting the most significant effect. Specifically, for rice farmers who joined agricultural cooperatives, who thought the agricultural machinery costs were acceptable, and who had paddy fields with a higher concentration degree, the probability of the adoption of three or more LATs would increase by 18.05%, 3.81%, and 0.11%, respectively (21.97% in total). In addition, the key determinants of rice farmers' decisions to adopt three or more LATs were divided into three levels, i.e., surface factors, middle-level factors, and deep factors. To promote LATs, policymakers should offer targeted incentives, such as agricultural machinery purchase subsidies, technical guidance, and agricultural cooperative services. [ABSTRACT FROM AUTHOR]

This paper was originally prepared for a roundtable on 'Chinese Environmental History: Current Research and Future Prospects' at the Eighth International Convention of Asia Scholars. This is a large and complex topic covering a broad range of disciplines. Except for those publications which clearly marked their titles as 'environmental history,' it is difficult for us to classify which is indeed a study of 'environmental history,' let alone provide a comprehensive summary of the current research of Chinese environmental history. However, I would like to share with you my view on this topic from the perspective of historical geography. This paper consists of the current research of Chinese environmental history, its relationship with Chinese historical geography and my view on its future prospects. [ABSTRACT FROM AUTHOR]

Process interactions on catenas have supported grazing adapted ecosystems and sustained biodiversity values in the source zone of the Yellow River in western China for millennia. In recent decades, anthropogenic disturbance and climate change have threatened the integrity of these systems, impacting upon environmental values and their capacity to sustain local livelihoods. Collaborations between local experts and a team of international researchers during a workshop and field excursion to this area in July 2019 developed a cross-disciplinary, process-based model of alpine meadow catenas. This paper relates the contemporary health of these grassland-wetland systems to their 'best achievable state' under prevailing boundary conditions, differentiating stages of degradation and recovery in relation to climate and land use changes. Recovery is underway for alpine meadow catenas at Maqin. Reduced land use pressures (stocking rates) and longer growing seasons have enhanced grassland-wetland conditions. However, recovery prospects are limited for local areas of extremely degraded grasslands (heitutan), as breached abiotic thresholds have resulted in soil and nutrient loss and reduced capacity for water retention. While lagomorphs and rodents act as ecosystem engineers when alpine meadows are in a healthy state, irruptions locally increase the proportion of bare ground and inhibit recovery potential. Management options that support recovery of alpine meadows are presented for differing stages of degradation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Food security plays an important role in maintaining national stability and sustainable development of human society, and its research has become a hot issue at present. Shandong is the main grain producing area in China, and its grain production plays an important role in national food security. Accordingly, this paper is based on the county climate change, grain yield, sown area, fertilizer use, total power of rural machinery, and total population data in Shandong Province from 1995 to 2020. The evolution process of the food security pattern was studied by the methods of spatial analysis and comprehensive evaluation, the influencing factors of food security were quantitatively analyzed, and the adaptive countermeasures to alleviate the food security risks in this region were discussed. The results show that: Grain production increased by 30.62% from 1995 to 2020. The total population and per capita food availability also increased. Since 2000, more than a quarter of counties have experienced a high risk of food insecurity. The spatial agglomeration of grain production was enhanced, and the local agglomeration characteristics were significantly different. The average temperature in the growing season, the sown area, and the total power of agricultural machinery had a significant positive impact on grain production, while the annual average temperature had a significant negative impact on grain production. Improving the food supply system, strengthening the protection of cultivated land, improving the efficiency of fertilizer utilization, and increasing investment in agricultural science and technology can effectively alleviate food security risks. [ABSTRACT FROM AUTHOR]

The world currently faces an unprecedented phase of global environmental change largely driven by the combined impact of anthropogenic climate change and environmental degradation. Adaptation to global environmental changes in natural resource management is often hindered by high levels of uncertainty related to environmental impact projections. Management strategies and policies to support adaptation measures and sustainable resource management under substantial environmental uncertainty are thus urgently needed. The paper reports results of behavioral irrigation experiments with farmers and students in the region of Hangzhou in China. The experimental design simulates a small-scale irrigation system with five parties located along an irrigation channel. The first treatment adds weather variability with a drying tendency that influences water availability in the irrigation channel. In the second treatment, the participants can select one of two adaptation options. Our results suggest that participants react with a marked delay to weather uncertainty. In addition, upstream players are more likely to adapt to uncertainty than those further downstream, and groups who show higher levels of cooperation more frequently invest in adaptation measures. Lastly, extraction inequality in earlier stages is found to constitute a key obstacle to collective adaptation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Owing to the increasing anthropogenic activities, flood frequency analysis and flood control scheduling of reservoir become more and more complicated because of the non-stationarity of flood series. This paper aims to assess the effects that non-stationary flood series, which is affected by land use change of Daqing River Basin (in North China), has induced on the reservoir flood routing. And the analysis has been carried out in Xidayang Reservoir, which is located in south branch of Daqing River Basin of North China. In this paper, the annual maximum peak discharge series and the annual maximum flood volume (1-day, 3-day and 6-day) series of Xidayang Reservoir were selected to detect their variation using three steps change point diagnosis. Mixed distribution was employed to fit the non-stationary flood series, estimating parameters by simulated annealing algorithm. The results indicate that (1) mixed distribution provided a more appropriate and superior fit than conventional distribution (P3 distribution) to non-stationary flood series, (2) design flood values estimated by mixed distribution reduced by 0.03 %-20.24 % with different return periods compared with the results computed by conventional P3 distribution, and (3) through reservoir flood routing, the maximum water level and maximum discharge with various return periods considering the series' non-stationarity also showed a decrease by up to 0.56 m and 81.68 % respectively compared with the results regardless of the series' non-stationarity. These results provide a significant theoretical basis for flood control and water resources management in Daqing River Basin. [ABSTRACT FROM AUTHOR]

Drought, being one of the most devastating natural disasters, has a far- reaching impact. In the context of global warming, it becomes crucial to quantitatively and scientifically assess the effects of anthropogenic climate change on meteorological drought in China. This assessment not only enhances our understanding of anthropogenic climate change but also aids in formulating more effective strategies for managing the risks associated with meteorological drought. This study employs the standardized precipitation evapotranspiration index (SPEI) to compute drought events by utilizing both observational data and counterfactual climate data (i.e., detrended observations). Subsequently, it analyzes the impact of anthropogenic climate change on the characteristics of drought, including frequency, intensity, duration, and affected area, in China as well as nine major river basins from 1960 to 2019. The outcomes of the analysis reveal that based on observational data, there is a discernible upward trend in the frequency, intensity, duration, and affected area of meteorological droughts in China. Notably, the regions experiencing an increase in frequency, intensity, and duration are primarily situated in the northeastern part of the Northwestern Rivers basin, the central and western parts of the Yellow River basin, the central and northern parts of the Yangtze River basin, the western part of the Southeastern River basins, and the eastern part of the Pearl River basin. Conversely, when considering a counterfactual climate scenario, the frequency and intensity of meteorological droughts in China demonstrate an upward trend, while the duration and affected area exhibit a downward trend. The impact of anthropogenic climate change on China has been evident in the increased frequency, intensity, duration, and affected area of droughts. Specifically, regions located in the northeastern parts of Northwest River basins, the southern part of the Songliao River basin, the northern part of the Haihe River basin, the central- northern part of the Yangtze River basin, the eastern part of the Pearl River basin, and the western part of the Southwest River basins have experienced amplified levels of drought. Anthropogenic climate change is highlighted as the primary factor influencing the observed drought characteristics changes in China, with contribution rates of 84.67%, 75.25%, 190.32%, and 133.99% for changes in the increased drought frequency, intensity, duration, and affected area, respectively. These changes have significant implications for water resource management and agricultural practices in the affected regions. [ABSTRACT FROM AUTHOR]

The decomposition of taxonomic, phylogenetic, and functional beta diversity into their turnover and nestedness components could provide novel insights into biodiversity conservation, e.g., provide implications for the Single Large Or Several Small reserves debate (SLOSS debate). Due to dramatic climate change and massive anthropogenic activities in recent decades in North China, the wetlands and the associated biodiversity in this region have declined significantly. This study applied the taxonomic, phylogenetic, and functional beta diversity decomposition for the first time in wetland bird communities in North China, aiming to propose scientific and comprehensive suggestions for bird diversity conservation in this region. A paired t-test was used to compare the differences between taxonomic, phylogenetic, and functional turnover, and their nestedness components. In addition, a spearman correlation analysis was used to assess the associations between each explanatory variable (differences in mean annual temperature and mean annual precipitation, as well as spatial distances) and each beta diversity index. A total of 546 bird species were found in 38 wetlands in North China, with three critically endangered species, 19 endangered species, 22 vulnerable species, and 61 near threatened species. The number of threatened species (critically endangered, endangered, and vulnerable) found in these lakes was about 30% of all threatened species in China. The results showed that taxonomic and phylogenetic beta diversity among wetland bird communities in North China was mainly dominated by turnover, while functional beta diversity was mainly dominated by nestedness. Importantly, the phylogenetic and functional results showed similar patterns even after controlling for the effects of taxonomic beta diversity. In addition, the taxonomic and phylogenetic turnover was more associated with both climate variables and spatial distances than other components. The contrasting patterns among the taxonomic, phylogenetic, and functional decompositions of wetland bird communities in North China indicate that distinctive conservation strategies should be considered for different biodiversity dimensions. Specifically, the conservation of taxonomic and phylogenetic bird diversity in this region should focus on multiple wetlands, while the conservation of bird functional diversity should focus on a single wetland with high functional diversity. [ABSTRACT FROM AUTHOR]

• This paper conducts the assessment of CO2 storage capacity of offshore saline aquifers including Bohai Bay Basin in northern China, also Beibu Gulf Basin and Yinggehai Basin in southern China. • Different assessment methodologies are applied, and the mechanism and results are compared to analyze the applicability. • Results show that the CSLF and CO2BLOCK methods take into the account the storage mechanisms such as geological structure storage, residual gas storage and dissolution storage, the results seem more reasonable. Also different storage time interval could results in various capacity potential under safe injection in CO2BLOCK method. • In summary, the CO2 storage potential of Bohai Bay Basin, Beibu Gulf Basin, and Yinggehai Basin are 39.98, 53.22, and 13.37 Gt, respectively. Saline Aquifer CO 2 Storage (SACS) has become a vitally important technology for mitigating climate change brought on by anthropogenic and fossil fuel emissions. Application of SACS projects in offshore saline aquifers in China is quite promising, and the CO 2 storage technical and economic potential are considerable. However, the storage capacities achieved from different analytical and numerical methods varies a lot from each other since the main factors taken into account are variable. In this paper, different methodologies are applied to conduct the assessment of CO 2 storage capacity of offshore saline aquifers including Bohai Bay Basin in northern China, also Beibu Gulf Basin and Yinggehai Basin in southern China. Results show that the storage capacity obtained from European Commission's method is much less than that determined by the other three methods (i.e., USDOE, CSLF and CO2BLOCK method) since it mainly effected by the area of the saline aquifers. Since both of the CSLF and CO2BLOCK methods take into the account the storage mechanisms such as geological structure storage, residual gas storage and dissolution storage, the results seem more reasonable. In addition, the CO2BLOCK method considers the formation stability during injection as well, which is more in accordance with the reality. In summary, the CO 2 storage potential of Bohai Bay Basin, Beibu Gulf Basin, and Yinggehai Basin are 39.98, 53.22, and 13.37 Gt, respectively. This further verifies the great potential of industrial-scale pilot and demonstration CO 2 storage projects in offshore deep saline aquifers in China. [ABSTRACT FROM AUTHOR]

• Transition zones are the hotspots of bioclimatic changes under global warming. • Global warming extends growing season lengths but increases heat and water stresses. • Sustainable grasslands in China shrink and shift northwestward with global warming. Bioclimatic response to global warming is a key linkage between anthropogenic climate change and ecosystem sustainability, particularly for the impact-prone climate transition zones. This paper examines changes in heat-water conditions from 2006 to 2100 across China, using the fifth generation climate reanalysis from the European Centre for Medium-Range Weather Forecasts (ERA5) and bias-adjusted climate projections by the Coupled Model Intercomparison Project Phase 5 (CMIP5). We then assess the effects of these changes on habitat suitability for responsive ecosystems using a species distribution model. The results reveal significant changes in bioclimatic environments across dry–wet climate transition zones under the present-day climate and the RCP8.5 scenario. By the end of the 21st century, local growing season length (GSL) could extend by 60 days and 30 % of the GSL could be under heat stress. Water conditions worsen overall in both the air and the soil, despite some improvements in the middle parts of transition zones. With altered heat-water conditions, sustainable grasslands shift northwestward, with a reduction of approximately 131 million km2 (46.6 % relative to 2006–2010) in total area. These changes primarily arise from alterations in winter and spring heat-water conditions. Our findings highlight the climate transition zones as hotspots of ecosystem vulnerability demanding particular attention in impact assessment and adaptation studies. [ABSTRACT FROM AUTHOR]

Efforts to deal with anthropogenic environmental impacts are focussed predominantly on cities. This paper applies metafrontier-data envelopment analysis (DEA) to evaluate the capacity of 286 Chinese cities of different sizes and in different regions towards green growth development and assesses gaps in their efficiencies. The determinants of efficiency, including regional and population size effects, were estimated using logistic regression model. Results show that the state of green growth efficiency was different for cities of different sizes and from different regions, and gaps existed compared to the best production frontier. The paper suggests that more endeavours are required for environmental and social dimensions, and a short-term target can include achievement of group frontier efficiency and significant reduction in technology gap ratios. Owing to significant population size effect, policy programs should have target plans for cities of different sizes as they differ in performance and capacity building. [ABSTRACT FROM AUTHOR]

The species-area relationship (SAR) is a well-established, globally recognized ecological pattern, and research on SAR has expanded to include the phylogenetic diversity-area relationship (PDAR). However, this research has generally been limited to terrestrial systems. Using data on freshwater macroinvertebrates, the log–log form of the SAR and PDAR power models were compared between the Lhasa River and the Niyang River on the Tibetan Plateau in China. The study reveals that there is a significant difference in the slopes of SAR and PDAR between the two rivers, with the Lhasa River having a considerably higher slope. The beta diversity calculations in these two basins support this pattern, with the Lhasa River exhibiting significantly higher numbers of species and greater total phylogenetic beta diversity than the Niyang River. Regarding species replacement, the turnover component was the primary driver of both species and phylogenetic beta diversity in both rivers. These differences in the beta diversity components were mainly driven by dispersal constraints because spatial distance had a large effect on total beta diversity and turnover fractions. In addition, the nestedness component was more affected by climate and land cover, indicating that highland rivers are subject to the threats of anthropogenic disturbance and climate change. Therefore, spatial factors play a crucial role in determining the distribution of passively dispersed benthic organisms as the scale of change in rivers increases from local to regional effects. [ABSTRACT FROM AUTHOR]

Quantifying the relative influences of anthropogenic activities and climate change on soil erosion and deposition during the Holocene, when both forces have been interacting is a complex problem. Analysis of long-term patterns in soil erosion and lake deposition in a basin can provide the basis for untangling the complexities of climate and anthropogenic forcings. In this paper, sedimentary sequences from Xingyun Lake are compared with simulated soil erosion rates in the basin to explore the relationship between river basin soil erosion and lake deposition during the Holocene in Yunnan, China. Modern soil erosion rates are calculated using RUSLE, while Holocene soil erosion rates are estimated using modern rates with reconstructed precipitation and vegetation cover sequences. Through this investigation, we found the following results. First, Holocene vegetation in the lake basin was mainly affected by climate change, and the vegetation experienced the same pattern of changes as the climate. Soil erosion and lake deposition rates, along with changes to vegetation cover, were synchronous with precipitation trends during the Holocene. Second, soil erosion and lake deposition have been exacerbated by human activities, such as deforestation and land reclamation in the Xingyun Lake basin. Finally, this study provides new insights into the effects by anthropogenic impacts and climate forcing on the processes of soil erosion and lake deposition on the millennium scale. [ABSTRACT FROM AUTHOR]

In order to better understand air pollution in deve-loping regions, such as China, it is important to investigate the wet deposition behavior of atmospheric trace metals and its sources in the subtropical watershed. This paper studies the seasonal change of trace metal concentrations in precipitation and other potential sources in a typical subtropical watershed (Jiazhuhe watershed) located in the downstream of the Yangtze River of China. The results show that typical crustal elements (Al, Fe) and trace element (Zn) have high seasonal variation patterns and these elements have higher contents in precipitation as compared to other metals in Jiazhuhe watershed. In addition, there is no observed Pb in base flow in this study, and the concentration magnitudes of Al, Ba, Fe, Mn, Sr, and Zn in base flow are significantly higher than that of other metals. During different rainfall events, the dynamic export processes are also different for trace metals. The various trace metals dynamic export processes lead to an inconsistent mass first flush and a significant accumulative variance throughout the rainfall events. It is found that in this region, most of the trace metals in precipitation are from anthropogenic emission and marine aerosols brought by typhoon and monsoon. [ABSTRACT FROM AUTHOR]

Under climate change and anthropogenic activities, the homogenization of fish communities shows spatial and temporal shifts and threatens biodiversity and ecosystem functioning, but little effort has been made to assess the seasonal shift of spatial homogenization in marine demersal fish, which hinders effective management. In the present study, we investigated the spatial patterns of demersal fish communities and their seasonal changes in the shelf sea of Shandong Peninsula in northeast China based on the four seasonal surveys. Our findings showed that both season and region were important factors in the distributions of biodiversity and the community structure of demersal fish. Spatial homogenization of taxonomic structure and functional structure exhibited inconsistent changes with season. Compared with taxonomic structure, functional structure exhibited relatively lower spatial homogenization in all seasons. Our results suggest that the density of survey stations for demersal fish resource investigation in the study area should be conducted in at least four regions and considering seasonality. This study highlights a need to understand spatial homogenization and its seasonal changes in demersal fish in both taxonomic and functional approaches, which could give insight into biodiversity and resource state and be conducive to improving the efficiency of resource investigation and management. • This paper investigated spatial homogenization of fish communities in the shelf sea of Shandong Peninsula. • A trait-based approach was used to measure functional structure of fish community. • Spatial homogenization of taxonomic and functional structures have different seasonal patterns. • The findings provide reference in optimization of survey station and determination of protected area scope. [ABSTRACT FROM AUTHOR]

In recent decades, China has experienced substantial climate change and significant vegetation greenness due to the extensive implementation of artificial ecological restoration programs. However, the quantitative contributions of climatic and anthropogenic drivers to the national variations in associated evapotranspiration (ET) and gross primary productivity (GPP) over China at different climate zoning sub-regions remain unclear. Based on the analysis of climate factor and vegetation disturbance trends created by anthropogenic activities, this study constructed a remote sensing-based ecological model consisting of Penman–Monteith–Leuning (PML) and light use efficiency (LUE) components. The proposed model simulated the spatiotemporal changes in ET and GPP between 1999 and 2018 over China. The contributions of climatic factors and anthropogenic activities to ET and GPP variations were quantitatively calculated by ridge regression. The results show that (1) both interannual ET and GPP markedly increased, by 1.32 mm yr−1 and 8.01 g C m−2 yr−1, respectively; (2) vegetation changes due to anthropogenic disturbance made the dominant contribution to GPP variations over China, while the dominant factor influencing ET changes differed by sub-region due to the joint effects of vegetation and climate; (3) temperature and precipitation positively affected ET, while wind speed, humidity, and solar radiation negatively contributed to ET in most parts of Mainland China. These findings may provide a workable, scientific reference for further ecological restoration decision-making processes in China. [ABSTRACT FROM AUTHOR]

Monitoring shoreline movements is essential for understanding the impact of anthropogenic activities and climate change on the coastal zone dynamics. The use of remote sensing allows for large-scale spatial and temporal studies to better comprehend current trends. This study used Landsat 5 (TM), Landsat 8 (OLI), and Sentinel-2 (MSI) remote sensing images, together with the Otsu algorithm, marching squares algorithm, and tidal correction algorithm, to extract and correct the coastline positions of the east coast of Laizhou Bay in China from 1984 to 2022. The results indicate that 89.63% of the extracted shoreline segments have an error less than 30 m compared to the manually drawn coastline. The total length of the coastline increased from 166.90 km to 364.20 km, throughout the observation period, with a length change intensity (LCI) of 3.11% due to the development of coastal protection and engineering structures for human activities. The anthropization led to a decrease in the natural coastline from 83.33% to 13.89% and a continuous increase in the diversity and human use of the coastline. In particular, the index of coastline diversity (ICTD) and the index of coastline utilization degree (ICUD) increased from 0.39 to 0.79, and from 153.30 to 390.37, respectively. Over 70% of the sandy beaches experienced erosional processes. The shoreline erosion calculated using the end point rate (EPR) and the linear regression rate (LRR) is 79.54% and 85.58%, respectively. The fractal dimension of the coastline shows an increasing trend and is positively correlated with human activities. Coastline changes are primarily attributed to interventions such as land reclamation, aquaculture development, and port construction resulting in the creation of 10,000.20 hectares of new coastal areas. Finally, the use of Kalman filtering for the first time made it possible to predict that approximately 84.58% of the sandy coastline will be eroded to varying degrees by 2032. The research results can provide valuable reference for the scientific planning and rational utilization of resources on the eastern coast of Laizhou Bay. [ABSTRACT FROM AUTHOR]

Ozone pollution in eastern China has become one of the top environmental issues. Quantifying the temporal trend of surface ozone helps to assess the impacts of the anthropogenic precursor reductions and the likely effects of emission control strategies implemented. In this paper, ozone data collected at the Shangdianzi (SDZ) regional atmospheric background station from 2003 to 2015 are presented and analyzed to obtain the variation in the trend of surface ozone in the most polluted region of China, north of eastern China or the North China Plain. A modified Kolmogorov- Zurbenko (KZ) filter method was performed on the maximum daily average 8 h (MDA8) concentrations of ozone to separate the contributions of different factors from the variation of surface ozone and remove the influence of meteorological fluctuations on surface ozone. Results reveal that the short-term, seasonal and long-term components of ozone account for 36.4, 57.6 and 2.2% of the total variance, respectively. The long-term trend indicates that the MDA8 has undergone a significant increase in the period of 2003-2015, with an average rate of 1.13±0.01 ppb year-1 (R² = 0:92). It is found that meteorological factors did not significantly influence the long-term variation of ozone and the increase may be completely attributed to changes in emissions. Furthermore, there is no significant correlation between the longterm O3 and NO2 trends. This study suggests that emission changes in VOCs might have played a more important role in the observed increase of surface ozone at SDZ. [ABSTRACT FROM AUTHOR]

Based on observations and historical simulations from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) archive, the contributions of human activities (including greenhouse gases (GHGs), anthropogenic aerosols (AAs), and land use (LU)) and external natural forcings (Nat) to climate changes in China over the past 50 years were quantified. Both anthropogenic and external natural forcings account for 95%-99% of the observed temperature change from 1951-1975 to 1981-2005. In particular, the temperature changes induced by GHGs are approximately 2-3 times stronger than the observed changes, and AAs impose a significant cooling effect. The total external forcings can explain 65%-78% of the observed precipitation changes over the past 50 years, in which AAs and GHGs are the primary external forcings leading to the precipitation changes; in particular, AAs dominate the main spatial features of precipitation changes in eastern China. Human activities also dominate the long-term non-linear trends in observed temperature during the past several decades, and, in particular, GHGs, the primary warming contributor, have produced significant warming since the 1960s. Compared to the long-term non-linear trends in observed precipitation, GHGs have largely caused the wetting changes in the arid-semiarid region since the 1970s, whereas AAs have led to the drying changes in the humid-semihumid region; both LU and Nat can impose certain impacts on the long-term non-linear trends in precipitation. Using the optimal fingerprinting detection approach, the effects of human activities on the temperature changes can be detected and attributed in China, and the effect of GHGs can be clearly detected from the observations in humid-semihumid areas. However, the anthropogenic effects cannot be detected in the observed precipitation changes, which may be due to the uncertainties in the model simulations and to other issues. Although some results in this paper still need improvement due to uncertainties in the coupled models, this study is expected to provide the background and scientific basis for climate changes to conduct vulnerability and risk assessments of the ecological systems and water resources in the arid-semiarid region of China. [ABSTRACT FROM AUTHOR]

Discharge from the largest karst spring in north China, the Niangziguan Springs, has been declining since the 1950s. This paper examines the response of these springs to climatic change and anthropogenic influence by attempting a model-based discrimination between phases in the stream discharge record. In Niangziguan Springs Basin, the exploitation of karst groundwater began in 1979. Accordingly, the spring discharge data were divided into two phases: pre-1979 and post-1979. In the first phase (1957-78) the spring discharge was believed to be affected solely by climate change, and in the second phase (1979-2007) the spring discharge was influenced by both climate change and human activities. Using grey system theory, a discharge model was estimated for the first phase. Extrapolating the model, we obtained a projection of the spring discharge during the second phase. Using a water balance calculation, we discerned the respective effects of climate change and human activities on depletion of spring discharge for the second phase. The results show that the contribution of climate change to depletion of Niangziguan Springs is 2.30m3/s and the contribution of anthropogenic activities ranges from 1.89 to 2.90 m3/s, although this assumes a constant for the climate change effect. Accordingly, the anthropogenic effects have been approaching and surpassing the effects of climate change during the second phase. With respect to the impact of human activities on spring discharge, groundwater abstraction accounts for only about 34-52% of the declines; 48-66% of the declines are related to other human activities, such as dewatering from coal mining, dam building and deforestation. [ABSTRACT FROM AUTHOR]

The hydrologic data series are nonstationary due to climate change and local anthropogenic activities. The existing nonstationary design flood estimation methods usually focus on the statistical nonstationarity of the flow data series in the catchment, which neglect the hydraulic approach, such as reservoir flood regulation. In this paper, a novel approach to comprehensively consider the driving factors of non-stationarities in design flood estimation is proposed, which involves three main steps: (1) implementation of the candidate predictors with trend tests and change point detection for preliminary analysis; (2) application of the nonstationary flood frequency analysis with the principle of Equivalent Reliability (ER) for design flood volumes; (3) development of a nonstationary most likely regional composition (NS-MLRC) method, and the estimation of a design flood hydrograph at downstream cascade reservoirs. The proposed framework is applied to the cascade reservoirs in the Han River, China. The results imply that: (1) the NS-MLRC method provides a much better explanation for the nonstationary spatial correlation of the flood events in Han River basin, and the multiple nonstationary driving forces can be precisely quantified by the proposed design flood estimation framework; (2) the impacts of climate change and population growth are long-lasting processes with significant risk of flood events compared with stationary distribution conditions; and (3) the swift effects of cascade reservoirs are reflected in design flood hydrographs with lower peaks and lesser volumes. This study can provide a more integrated template for downstream flood risk management under the impact of climate change and human activities. [ABSTRACT FROM AUTHOR]

The Hanjiang River, as a water donor basin, plays a fundamental role in supporting water supply security in northern China while maintaining the health and stability of ecosystems within the basin. However, the combined influence of climate change and anthropogenic interference has resulted in a significant change in the flow regime of the basin, challenging the sustainability of the river system. In order to understand the impact of the above factors on the river runoff, we analyzed the temporal and spatial pattern of runoff and climate factors in the basin and quantitatively assessed the contribution of climate change and human activities to the change in runoff using the elasticity coefficient method. Our results indicate that annual runoff has experienced a significant downward trend over the past 60 years, which is projected to continue into the future. It is also found that the temporal pattern of the runoff regime differed upstream and downstream of the Danjiangkou Reservoir due to the joint operation of the reservoir and China's Middle Route Project of South-to-North Water Diversion (MRP-SNWD). A significant decrease in runoff was primarily attributed to human activities, followed by precipitation. In contrast, evapotranspiration had the least effect. In particular, the MRP-SNWD was a significant anthropogenic factor, contributing to about 20.3% of the total change in runoff. Our results highlighted the unfavorable effects of human activity on the hydrological system in the Hanjiang River and provided some constructive suggestions to turn vulnerability into resilience. [ABSTRACT FROM AUTHOR]

Ecosystem services (ESs) are important for supporting human development. However, a changing climate and anthropogenic impacts are resulting in the degradation of dryland ecosystems to varying degrees. While there has been the global implementation of Ecological Restoration Programs (ERPs) to restore degraded ecosystems, there remains limited comprehensive assessment of their impacts on ESs of drylands. In this study, the sandy areas of northern China were used as the study area. The RUSLE, RWEQ, CASA, and InVEST models were used to simulate four major ESs: soil conservation (SC), sand fixation (SF), carbon sequestration (CS), and water yield (WY). The study aimed to evaluate the influences of various ERPs on major ESs. The dominant factors affecting the overall benefits provided by ESs were also identified. Since ERPs were implemented, forest areas have increased by 2.8 × 104 km2, whereas the areas of cropland, shrubland, and grassland have decreased. There were generally increasing trends in SF, SC, and CS, whereas there was a decreasing trend in WY. We then used a scenario-based simulation approach to eliminate the influence of climate variability on ESs. The results showed increasing trends in SF, SC, and CS, whereas there were minimal changes in WY. The results suggested that although ERPs can significantly increase regional ESs, unregulated expansion in vegetation can result in a water crisis and affect regional water security. [ABSTRACT FROM AUTHOR]

Variations in runoff and sediment discharge are important characteristic variables for revealing the coupled effects of climate change (including both the natural variability of climate and anthropogenic climate change) and human activities (including soil and water conservation measures, land use changes, and hydraulic engineering construction). Based on the meteorological data from 19 meteorological stations and the hydrological data from the watershed control station of Hongqi Station, the temporal and spatial evolution of runoff and sediment discharge and the water–sand relationship were analyzed, and the response mechanisms of runoff and sediment discharge changes were clarified using Mikhail Budyko's theory and other qualitative and quantitative methods. The results determined that: (1) The runoff and sediment discharge showed significant downward trends, with linear change rates of −0.28 × 108 m3/a and −46.10 × 104 t/a, respectively. The change points of the runoff and sediment discharge occurred in 1987 and 1996, respectively. (2) The spatial distribution of water and sediment was different, and the upper and middle reaches produced water, while the downstream produced sediment. (3) Comparing potential evapotranspiration and rainfall based on Budyko theory and the regression relationship, runoff is more closely related to rainfall, and runoff changes are more affected by it. The change in sediment discharge is most closely related to sediment concentration, followed by rainfall and potential evaporation. (4) The contribution rates of runoff and sediment discharge changes influenced by climate change were 24% and 3%, respectively, and the contribution rates by human activities were 76% and 97%, respectively. Human activities, including soil and water conservation measures, land use changes, and hydraulic engineering construction were the main influencing factors, and the impacts of human activities increased from 1960 to 2019. The research results are of great significance for erosion control and ecological restoration in the Tao River Basin under the conditions of the changing environment. [ABSTRACT FROM AUTHOR]

Aim: Significant changes in species elevational ranges in mountains have been repeatedly documented, yet the direction, magnitude and drivers of these shifts remain controversial. Presently, there is still lacking evidence about the general nature of species elevational range shifts in eastern Eurasia in response to anthropogenic climate change. By using historical specimen records and recent field observations for 735 seed plant species across 29 China's mountains, we assessed changes in species' elevational centroids and their drivers. Location: China. Time Period: 1950–2018. Major Taxa Studied: Seed plant species. Methods: The elevation records of all sampled occurrences in each mountain during the two time periods were estimated, and the null models were developed to test the sampling bias. Ecological niche models (ENMs) were used to evaluate the relative importance of climate factors in constraining each species distribution. Generalized linear models (GLMs) to test the relationships between the centroid elevational range shifts of species and different divers. Results: We found that 54% of the species shifting upward and 46% downhill. However, species' elevational shifts significantly differed among species and mountains. Herbaceous and lowland species moved upward faster than woody and high‐elevation species. Species in temperate mountains and in mountains with taller elevational gradients moved upward, while species in subtropical mountains and in mountains with shorter elevational gradients moved downward. Precipitation changes experienced by species, species' climatic adaptations, several species' functional traits and mountain size all contributed to explain the magnitude of species' centroid elevational range shifts. Main Conclusions: Our results highlight complex biodiversity redistribution of seed plants across Chinese mountains, not necessarily conforming to the trend of species upward shifts in elevation. Changes in precipitation regimes may blur the simplistic assumption of isotherm tracking. This study fills an important geographic shortfall for our understanding of biodiversity redistribution under anthropogenic climate change. [ABSTRACT FROM AUTHOR]

Global dryland areas are vulnerable to climate change and anthropogenic activities, making it essential to understand the primary drivers and quantify their effects on vegetation growth. In this study, we used the Time Series Segmented Residual Trends (TSS-RESTREND) method to attribute changes in vegetation to CO 2 , land use, climate change, and climate variability in Chinese and American dryland areas. Our analysis showed that both Chinese and American drylands have undergone a greening trend over the past four decades, with Chinese greening likely linked to climatic warming and humidification of Northwest China. Climate change was the dominant factor driving vegetation change in China, accounting for 48.3%, while CO 2 fertilization was the dominant factor in American drylands, accounting for 47.9%. However, land use was the primary factor resulting in desertification in both regions. Regional analysis revealed the importance of understanding the drivers of vegetation change and land degradation in Chinese and American drylands to prevent desertification. These findings highlight the need for sustainable management practices that consider the complex interplay of climate change, land use, and vegetation growth in dryland areas. [ABSTRACT FROM AUTHOR]

Purpose: In view of a lack of evidence on the effectiveness of climate change education (CCE) in China, this study aims to evaluate if a CCE course newly designed based on research recommendations and implemented with established pedagogy was effective in changing the beliefs and attitudes of first-year science students. Design/methodology/approach: This study took a simple longitudinal approach with surveys administered at the beginning and the end of the course and the differences in the responses analyzed with nonparametric statistical analyses. Findings: The results showed that the course produced significant changes in the beliefs concerning the anthropogenic causes of climate change and vulnerability to its impacts, which results in inequality of the impacts received. However, the course did not produce significant attitudinal changes among the students. Spearman's correlation, which affirmed the belief–attitude association, revealed that the students already had desirable attitudes toward climate change and these attitudes had not been reinforced. The students' perception of the importance of local government in climate action increased by the end of the course. Multimedia-aid learning, debates and discussions were useful in conveying the concepts of responsibility, ethics and vulnerability, but the addition of student-led community projects will increase personal significance of the course. Research limitations/implications: This study is instrumental for the development of a regional model of CCE in the mainstreaming of education for sustainable development in China, knowing that the regional approach is crucial to address the nuances in climate change knowledge, hence conceptions and beliefs across regions and, even, between different sectors of a region. This regional experience could also serve as a reference for other similar settings, particularly those of the developing countries. Originality/value: This study presents one of the very few studies dedicated to gauging the effects of CCE in China, particularly of a newly developed climate change course, on the beliefs and attitudes of students. This permits pedagogical development and continuous improvement of CCE in China. [ABSTRACT FROM AUTHOR]

High-resolution hydrological modeling is crucial for detecting extreme hydrological events and understanding fundamental terrestrial processes. However, spatial resolutions in current hydrological modeling studies have been mostly constrained to relatively coarse resolution (~10–100 km), and they therefore have a difficult time addressing flooding or drought issues with fine resolutions. In this study, a continental-scale high-resolution hydrological modeling framework (0.0625°, ~6 km) driven by remote sensing products was used to detect extreme hydrological event occurrences in China and evaluated based on the Variable Infiltration Capacity (VIC) model. The results showed that the developed model provided more detailed information than the coarser resolution models (a 0.25° and 1°), thereby capturing the timing, duration, and spatial extent of extreme hydrologic events regarding the 2012 Beijing flood and 2009/10 drought in Hai River Basin. Here, the total water storage changes were calculated based on the VIC model (−0.017 mm/year) and Gravity Recovery and Climate Experiment (GRACE) satellite (−0.203 mm/year) to reflect the water availability caused by climate change and anthropogenic factors. This study found that the 0.0625° dataset could capture detailed changes, thereby providing reliable information during occurrences of extreme hydrological events. The high-resolution model integrated with remote sensing products could be used for accurate evaluations of continental-scale extreme hydrological events and can be valuable in understanding its long-term occurrence and water resource security. [ABSTRACT FROM AUTHOR]

Zooplankton community could be affected by aquatic environment, land use patterns, and climate factors. However, few studies have evaluated the relative importance of these factors to the zooplankton community succession on a long-term scale. In this study, long-term data were used to analyze the succession characteristics and drivers of zooplankton communities in Honghu Lake, a large-scale shallow lake in central China. Results showed that zooplankton community structure changed greatly in 1959–2021. In general, the species number decreased, abundance and biomass increased, and the number and proportion of pollution tolerant species among dominant species increased during the past ~ 60 years. For the driving factors of zooplankton from 1992 to 2021, redundancy analysis showed that nutrients, wind speed, and aquaculture enclosure and pond were the main drivers of Protozoa and Rotifera, while phytoplankton abundance, wind speed, dissolved oxygen, and farmland were the main drivers of Cladocera and Copepoda. Generalized additive model showed that the aquatic environment had the highest direct explanation (mean is 60.2%) to zooplankton variation, followed by land use (mean is 35.6%) and climate factors (mean is 33.1%). Variance partitioning analysis showed that the effects of human activities (32.9–43.1%) associated with land use, water quality, and phytoplankton on the zooplankton succession are stronger than that of climate factors (19.9–29.2%). Additionally, lake eutrophication is an important factor for the decline in the richness index (p = 0.0017, r = − 0.8411) and Shannon index (p = 0.0301, r = − 0.8020) of zooplankton from 2019 to 2021. Our results highlighted that anthropogenic activity has stronger driving effects on zooplankton succession in the long term than climate changes in the lake. These findings can provide insights into zooplankton conservation in response to global climate change and complex anthropogenic actions. [ABSTRACT FROM AUTHOR]

Terrestrial water storage (TWS) is a critical component for sustainable societal development and ecosystem cycles. The Gravity Recovery and Climate Experiment satellites have tracked changes in global TWS under the combined effects of various factors with unprecedented accuracy since 2002. In this study, we separate the trends in TWS driven by precipitation and non‐precipitation factors for the Chinese mainland from 2003 to 2016 based on the statistical reconstruction method and linear regression and analyze the driving mechanisms combining with multi‐source data. The results show that: (a) during the study period, TWS shows different degrees of increase in most of the Yangtze River basin, the northern part of the Tibetan Plateau, and part of the Heilongjiang Province, while TWS shows a significant decrease in the Tien Shan Mountains, the southeastern part of the Tibetan Plateau, and the North China Plain; (b) precipitation is one of the dominant factors leading to the rise of TWS, and the construction of reservoirs and dams also contributes. In contrast, anthropogenic activities (agricultural irrigation, industrial water use, etc.) and accelerated glacial melting due to global warming are the dominant factors in the decline of water storage; (c) the contribution of long‐term precipitation change to water storage is significantly larger in the northern China region (north of the 800 mm isopleth). This study provides a feasible method for quantifying the contribution of precipitation and non‐precipitation factors to TWS, which is meaningful for understanding the impact of climate change and anthropogenic factors on water resources. Plain Language Summary: Water scarcity is a global crisis for social development in the present and future. As the world's most populous country, China's per capita freshwater resources are far below the global average, making the imbalance between water supply and demand in China even more serious. The study of water storage changes contributes to understanding freshwater resources in China. Here, the precipitation‐ and non‐precipitation‐ driven water storage changes in China are separated based on the statistical reconstruction method and long‐term precipitation data. In addition, satellite gravity, model simulations, and in‐situ data are combined to analyze the driving mechanism in regions that experienced significant changes in water storage during the past decades. Human activities and glacier melting are the dominant factors leading to the water storage deficit. Both precipitation and dam construction contribute to the increase in water storage. This study would provide valuable information for the rational allocation of water resources and coordinated development of the economy and ecology. Key Points: Terrestrial water storage (TWS) trends induced by long‐term precipitation change, precipitation variability, and non‐precipitation factors are separated in ChinaThe TP‐TWS factor is proposed to characterize the impact of long‐term precipitation trends on the TWS trendsThe TWS changes in typical regions are rationalized from the perspective of precipitation and non‐precipitation factors [ABSTRACT FROM AUTHOR]

Growing evidence has shown substantial threats to China's environment. After exceeding the United States in 2006, China became the world's largest CO2 emitter and accounted for 29 percent of global CO2 emissions in 2013. In this paper, I adopt perspectives from environmental sociology and examine the anthropogenic drivers of environmental disruption. I draw on the Impact = Population x Affluence x Technology (IPAT) framework and the Treadmill of Production (TOP) perspective to ground the analyses theoretically. I then analyze data for 30 Chinese provinces both temporally (from 1997 to 2009) and spatially (across the east, central, and west regions). From a temporal perspective, the findings suggest a concomitant growth of CO2 emissions, GDP per capita, and population. From a spatial perspective, Global Information System (GIS) analysis displays the overlapping of high CO2 emissions, GDP per capita, and population in East China in comparison with Central and West China. Through calculating and mapping the statistics, the GIS results can inform the spatial variations of environmental outcomes and complement the results from longitudinal analysis. Overall, the findings confirm the IPAT framework and reinforce the TOP argument. These findings also expand the existing cross-national inquiries about climate change. [ABSTRACT FROM AUTHOR]

Ecological civilization construction has become one of the key strategies to address China's serious resource and environmental issues. However, how to define and how to assess ecological civilization ( EC ) are worth further exploring. This paper constructed a people-oriented EC indicator system, composed of a set of indicators, viz. Degree of Physiological Equilibrium ( DPE ), Degree of Psychological Imbalance ( DPI ), Degree of Imbalance of Human and Environment ( DIHE ), Degree of Human Development ( DHP ), Disharmony Degree of Economy and Environment ( DDEE ), and a composite index-Ecological Civilization Index (ECI), and then the indicator system was used to investigate the trends of China's EC construction during 1980–2010. Based on the reference year 1980, the study revealed that: (1) Physiological equilibrium of Chinese people has been slightly disturbed; (2) Psychological balance of Chinese people has been broken seriously; (3) The balance between human and environment has been destroyed greatly; (4) China has achieved great progress in promoting human development; (5) this country has improved the relationship between economy and environment obviously, despite that this improvement pace still falls behind speed of economic growth; and (6) China's EC level has declined during this study period. Therein, psychological problem and conflict between human and environment are the key obstacles to China's EC progress. China's government should further emphasize reform of its income distribution system and transformation of its economic development mode in the future. [ABSTRACT FROM AUTHOR]

Grassland ecosystems are an important part of terrestrial ecosystems and are important for building ecological barriers, promoting the pastoral economy, and maintaining social stability. In recent decades, grasslands in northern China have undergone extensive degradation due to the combined effects of global climate change and the anthropogenic overuse of grasslands. An understanding of the spatial distribution of grassland degradation species is helpful for evaluating the process of grassland degradation and formulating appropriate protective measures. This is important for grassland degradation monitoring. To address the limitations of traditional ground surveys and realize intelligent remote sensing grassland degradation monitoring tasks, we use unmanned aerial vehicle (UAV) hyperspectral remote sensing technology to collect data on vegetation species in desert grasslands. In this paper, we propose a local-global feature enhancement network (LGFEN) for the classification of desert grassland species. The method uses the local feature enhancement (LFE) module and global feature enhancement (GFE) module to extract local and spatial information from hyperspectral images (HSIs), respectively. In addition, the introduction of the convolutional block attention module (CBAM) refines the features of HSIs, improving the stability of the classification performance. The results show that the proposed method has superior classification performance compared with existing HSI classification methods. With only 10 training samples per class, the overall accuracy, average accuracy, and kappa coefficient of the proposed method were 98.61%, 97.61%, and 0.9815, respectively. The proposed method provides a new approach for high-precision and high-efficiency dynamic monitoring of grassland ecosystems. • A local-global feature enhancement network (LGFEN) is proposed. • Improved efficiency of grassland degradation monitoring. • The LFE module is proposed to implement global feature extraction. • Compared with existing methods, LGFEN has better performance. [ABSTRACT FROM AUTHOR]

Climate change and anthropogenic replantation are supposed to greatly change vegetation coverage and ecosystem stability and functions, e.g., net primary productivity (NPP), evapotranspiration (ET) and water use efficiency (WUE). Our study compared WUE of nature- and human-induced forest cover increase on the Loess Plateau since 2000 using satellite-derived Vegetation Continuous Fields (VCF), NPP, ET. This study also applied over 30 years of model-based NPP and meteorological observations to compare the stability and changes brought up by the Grain for Green Project. The result showed that the average forest coverage fraction increased from 7.1% (~4.5 × 104 km2) in 2000 to 11.2% (~7.3 × 104 km2) in 2014. Artificial forest cover increase occupied 76.43% of the significantly increasing tree cover regions. The role of revegetation practice in NPP and ET became gradually more dominant than climate factors in artificial forests from the northern to the southern part of the Loess Plateau. For areas experiencing limited forest coverage increase, artificial forest areas showed higher WUE than natural forest areas under similar mean annual precipitation (MAP). The difference in stability was small between neighboring natural and artificial forest areas. The northwest of the Loess Plateau had an increasing resilience, whereas the south of the Plateau had an increased resistance to precipitation and temperature change. The higher dependency of the northern reforested areas on climate fluctuation indicates a growing threat of water scarcity to the sustainability of anthropogenic reforestation in semi-arid regions. [ABSTRACT FROM AUTHOR]

Existing analytical accounts of China's interactions with international law are underdeveloped. This article proposes the use of an interactional model to explain the normativity of international law from three perspectives: shared understandings, normative qualities of international law, and the reception of individual countries to these normative qualities. Furthermore, the interactional model is used to explain how conceptions of the normativity of international climate change law are developed in China. It finds that China has accepted the common responsibility system under an enhanced transparency framework, while adhering to the facilitative nature of international commitments to accommodate the needs of developing countries and stringently insisting on obligations of support from developed countries being met. In this, China's position on the normative qualities of international climate change law is influenced by its international identities, power status, national interests, and domestic understandings of anthropogenic climate change. The interactional account that follows implies that future research on China's interactions with international law should be cautious of both Western centrism and Chinese exceptionalism and consider both the legitimacy of international law and China's own domestic context. [ABSTRACT FROM AUTHOR]

[Display omitted] • Seasonal sampling of heavy metals in the groundwater was conducted in a subtropical mangrove wetland. • The enrichment trend of heavy metals exhibited seasonal variations along the intertidal transect. • COVID-19-induced attenuation of anthropogenic activity reduced terrestrial input of heavy metals to the sea. • The intertidal aquifer served as a buffer zone for the transport of heavy metals to the sea. Mangrove wetlands connecting the land and sea are critical and dynamic ecosystems which act as biogeochemical reactors that influence the concentrations and distributions of heavy metals in the groundwater and adjacent seawater. In this paper, a subtropical mangrove wetland in China was selected to investigate the spatiotemporal patterns of groundwater heavy metals and the driving mechanism along an intertidal transect with distinct undulated topography and vegetation zonation. Along the transect, five groundwater observation wells (W1-5) were set to collect groundwater samples at three different sediment depths (0.5, 1.2, and 2.0 m) and the advective flux between groundwater and surface water were calculated during four seasonal sampling campaigns from 2019 to 2020. The results showed that the seaward W1-3 acted as the groundwater discharge area while the landward W4-5 served as the surface water recharge area. The results of single-factor contamination index showed that a potential pollution risk of Hg existed at the study sites. The distribution of other heavy metals in the mangrove groundwater exhibited a seasonal variability along the transect during the sampling campaigns. For example, the relative high concentrations of Fe, Pb, Cu, Cr, and Zn focused in the landward zones in the dry seasons (autumn and winter 2019), whereas they changed to the seaward zones in the wet seasons (summer and autumn 2020). Moreover, the intertidal aquifer can act as a sink to enrich heavy metals in winter 2019 and autumn 2020 but become a source to discharge heavy metals to the sea in summer 2020. The above migration patterns of heavy metals were ascribed to the multiple complex factors including the seawater-groundwater interactions, vegetation zonation, biogeochemical reactions, and anthropogenic activities. This study contributed to the better understanding of heavy metal behaviors in mangrove groundwater so as to improve the sustainable management of mangrove wetlands under the pressure of anthropogenic activities and climate change. [ABSTRACT FROM AUTHOR]

Climate change and human activities significantly affected environmental changes in drylands. However, the relative roles remain unclear regarding these factors' effects on environment changes in drylands. Herein, we analyzed vegetation change trends using remote-sensing datasets to determine the interactions of vegetation, climate, and anthropogenic activities in an arid region of China, Kubuqi Desert. Our study showed that 67.64% of the pixels of fractional vegetation coverage (FVC) increased in 2020 in comparison with those of 1986. The FVC exhibited a significant greening trend (0.0011/yr, p < 0.05) in 1986–2020 as a whole. This greening trend revealed two distinct periods separated by a turning point in 2001. There was no clear trend of FVC before 2001, and then there was a dramatically greening trend since 2001 in most regions of the study area. The increasing rate (0.0036/yr) in the later period was three times higher than the entire period. The accelerated increasing trend was due to the variable compound effects of climate and human activities. The correlation between FVC and precipitation was mainly positive, which outweighs the significantly negative correlation between vegetation and temperature. However, both climatic factors cannot well explain the trends of vegetation dynamics, implying a possible role for human activities. Generally, climate change and anthropogenic activities contributed 42.15% and 57.85% to the overall vegetation variations in 1986–2020. Specifically, the relative role of the two factors was vastly different in two distinct periods. Climate change led the dominant roles (58.68%) in the vegetation variations in 1986–2001, while anthropogenic activities dominated (86.79%) in driving vegetation recovery in the period after 2001. Due to the massive ecological conservation programs such as the Grain for Green Project launched in 2001, substantial deserts have been transformed into grasslands and forests. This analysis highlights the ecological policies largely responsible for vegetation restoration and provides references for ecological protection and sustainable development in eco-fragile ecosystems. [ABSTRACT FROM AUTHOR]

Water supply is strategic for the development of society. The water distribution in nature follows patterns linked to geographic and territorial issues. Climate fluctuations aggravate shortage problems in semi-arid regions. This study aims to develop a systematic review of research on water scarcity in semi-arid areas through bibliometric methods that allow the analysis of its structure, performance, evolution, and future trends. The methodology considers three phases: (i) literature review, (ii) data cleaning and processing, and (iii) analysis of the research field and future trends. The intellectual structure of water scarcity in semi-arid zones covers 2206 documents with the collaboration of sixty-one countries, distributed in studies carried out in 54 years (1967 to 2021). This field of research has been growing, especially since the 21st century (93.1% of the documents). The countries that study the issue the most are those with high population rates and large consumption patterns, such as the United States and China. There are two central areas of interest led by the terms "water scarcity" and "water stress" due to the intensive use of the resource for agriculture and the management of the water–energy–climate nexus. Thus, the most significant journals studied relate remote sensing to resource management, and the most cited are related to agriculture. This research made it possible to consider future topics such as the study of anthropogenic effects and climate change, the accuracy and applicability of models, and future trends in conventional and unconventional agriculture and resources. [ABSTRACT FROM AUTHOR]

Quantifying the effects of climate change and human activities on runoff changes is the focus of climate change and hydrological research. This paper presents an integrated method employing the Budyko-based Fu model, hydrological modeling, and climate elasticity approaches to separate the effects of the two driving factors on surface runoff in the Luan River basin, China. The Budyko-based Fu model and the double mass curve method are used to analyze runoff changes during the period 1958~2009. Then two types of hydrological models (the distributed Soil and Water Assessment Tool model and the lumped SIMHYD model) and seven climate elasticity methods (including a nonparametric method and six Budyko-based methods) are applied to estimate the contributions of climate change and human activities to runoff change. The results show that all quantification methods are effective, and the results obtained by the nine methods are generally consistent. During the study period, the effects of climate change on runoff change accounted for 28.3~46.8% while those of human activities contributed with 53.2~71.7%, indicating that both factors have significant effects on the runoff decline in the basin, and that the effects of human activities are relatively stronger than those of climate change. [ABSTRACT FROM AUTHOR]

Surface water provides a basic resource for life and is vital for maintaining climate stability, hydrological cycles, and natural ecosystems. Lakes, which are an important part of surface water, play a crucial role in sustaining the hydrological balance and maintaining a healthy environment. The onset of climate change and anthropogenic disturbance on lakes and the environment, however, have drastically changed the morphological characteristics of lakes, leading to undesirable negative effects on the ecological environment. In recent years, many lakes around the world are undergoing phenomenal changes due to climate change and human activities. These changes have greatly affected the availability of freshwater resources, leading to a series of regional ecological and environmental problems, which constrain the regional sustainable development. Changes in lake parameters often indicate environmental change. Therefore, it is of great practical significance to extract lake water information to reflect the water quantity changes in the lake, understand its implications, and come up with timely solutions. This paper summarizes the existing research methods of lake water estimation in China and abroad and draws the following conclusions: (1) In the study of lake water volume estimation, it can be roughly divided into with topographic data and without topographic data. The most representative methods are the estimation methods based on topographic parameters and the Triangle Irregular Network (TIN) model method. In the actual research process, most of the scarce data that are difficult to obtain are lake topographic data, prompting researchers to constantly put forward new methods; (2) From the perspective of research methods, estimation of lake water volume can be divided into remote sensing-based and non-remote sensing-based research. With the continuous improvement of scientific and technological levels, current geographical researchers tend to use remote sensing to monitor lake water volume; (3) Although researchers have proposed a series of models for lake water volume estimation for the long-time process. However, many models are based on the ideal static estimation process, which poses challenges for researchers to make a long-term dynamic estimation of lake storage capacity in the future. At the same time, the accuracy of the model can be a problem that researchers need to work out solutions in the future. Finally, combined with the current development of remote sensing technology, the application potential and the future prospect of remote sensing in lake monitoring are briefly discussed. • Lake water volume estimation, it can roughly be divided into with topographic data and without topographic data. • Estimation of lake water volume can be divided into remote sensing-based and non-remote sensing research. • The application potential and the future prospect of remote sensing in lake monitoring are briefly discussed. [ABSTRACT FROM AUTHOR]

Contrasting landscape and climate settings generate different catenas for alpine steppe grasslands at Maduo (4200 m asl) and alpine meadow grasslands at Maqin (3750 m asl) on the Qinghai-Tibet Plateau. These place-based catenal models can be used as transferable archetypes in environmental management. [Display omitted] • Catenal models are developed for alpine steppe and alpine meadow grasslands on the QTP. • Implications for the generalised use of place-based catenal models are explored. • Research needs and management applications of the catenal models are scoped. Careful development of place-based catenal models and their application as transferable archetypes provides an integrative and generalisable framework for scientifically-informed approaches to environmental management. A workshop and field excursion to the Source Zone of the Yellow River in western China in July 2019 brought together local experts and a team of international researchers to co-develop cross-disciplinary, process-based catenal models that summarise controls on the character and behaviour of grassland environments in alpine meadow (3800 m asl) and alpine steppe (4200 m asl) landscapes. Water, sediment and nutrient fluxes, soil material properties, ground cover (especially percentage bare ground) and the role of small mammals (especially pika) are critical drivers of process linkages in the catenal models. Geologic, climatic and anthropogenic controls on these drivers vary in alpine steppe and alpine meadow settings. While these process interactions have supported grazing adapted ecosystems and sustained biodiversity values in this area for millennia, anthropogenic and climate change disturbances threaten the integrity of these landscapes and their capacity to provide ecosystem services and sustain livelihoods into the future. The place-based catenal models presented in this paper can be used to support applications that appropriately target key attributes, linkages and fluxes that may require conservation, maintenance or treatment in the management of alpine steppe and alpine meadow landscapes. [ABSTRACT FROM AUTHOR]

Lakes provide water-related ecosystem services that support human life and production. Nevertheless, climate changes and anthropogenic interventions remarkably altered lake and basin hydrology in recent decades, which pose a significant threat to lacustrine ecosystems. Therefore, assessments of lacustrine ecosystems require the spatial and temporal characteristics of key physical and human-dimensional attributes for lakes and lake basins. To facilitate stakeholders obtaining comprehensive data of lake basins in China, we compiled the comprehensive data set for China's lake basins (CODCLAB) mostly from publicly available data sources based on spatial analysis and mathematical statistics methods in this study. The CODCLAB is available in three data formats, including raster layers (Level 1) in "tiff" format, vector shapefiles (Level 2), and attribute tables (Level 3). It covers 767 lakes (>10 km2) in China and their basin extent associating with 34 variables organized into five categories: Hydrology, Topography, Climate, Anthropogenic, and Soils. This unique database will provide basic data for research on the physical processes and socioeconomic activities related to these lakes and their basins in China and expect to feed a broad user community for their application in different areas. Measurement(s) Hydrology, Topography, Climate, Anthropogenic, and Soils for China's lake basins Technology Type(s) spatial analysis and mathematical statistics Factor Type(s) CODCLAB_Level1 • CODCLAB_Level2 • CODCLAB_Level3 Sample Characteristic - Location China's lake basins [ABSTRACT FROM AUTHOR]

Climate change and anthropogenic factors have significantly impacted hydrological regimes, especially in semiarid regions. Using the trend‐free pre‐whitening Mann–Kendall (TFPW‐MK) test and linear regression, trends of precipitation, temperature, runoff, and water balances from different spatiotemporal scales were analysed during the past sixty years in the Upper Yongding River Basin (UYRB). Based on the Choudhury‐Yang equation, the contributions of climate change and human activities to runoff variation were further quantified in five mountainous catchments, and the actual effects of climate change and human activities on the water balance in the whole UYRB were also discussed. The results suggest that the UYRB has become much warmer and drier. The lower annual precipitation and intensity in summer were directly attributed to runoff reductions. Intra‐annual scale analyses of meteorological, hydrological and biological responses helped the comprehensive interpretation of the runoff trends. Human activities, including agricultural irrigation, were the main causes for runoff reduction, especially in the middle and lower reaches, and the contribution of human activities increased gradually in recent decades. The water balance changed drastically temporally, with the precipitation being converted less to runoff and more to evaporated fractions, which was also due to the second order effects of climate change and vegetation improvement. It is suggested that low water‐consumption plant species and the related water‐saving techniques in agriculture and afforestation should be introduced for the sustainable development in the similar regions. [ABSTRACT FROM AUTHOR]