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Understanding the spatial scaling of population stability is critical for informing conservation strategies. A recently proposed metric for quantifying how population stability varies across scales is the invariability-area relationship (IAR), but the underlying drivers shaping IARs remain unclear. Using 15-year records of 249 bird species in 1035 survey transects in North America, we derived the IAR for each species by calculating population temporal invariability at different spatial scales (i.e., number of routes) and investigated how species IARs were influenced by functional traits and environmental factors. We found that species with faster life history traits and reduced flight efficiency had higher IAR intercepts (i.e., locally more stable), whereas migratory species exhibited higher IAR slopes (i.e., a faster gain of stability with increasing spatial scale). In addition, spatial correlation in temperature and vegetation structure synchronized bird population dynamics over space and thus decreased IAR slopes. By demonstrating the joint influence of functional traits and environmental factors on bird population stability across scales, our results highlight the need for dynamic conservation strategies tailored to particular types of species in an era of global environmental changes.

Rapid biodiversity loss has triggered decades of research on the relationships between biodiversity and community stability. Recent studies highlighted the importance of species traits for understanding biodiversity–stability relationships. The species with high growth rates (‘fast’ species) are expected to be less resistant to environmental stress but recover faster if disturbed; in contrast, the species with slow growth rates (‘slow’ species) can be more resistant but recover more slowly if disturbed. Such a ‘fast–slow’ trait continuum provides a new perspective for understanding community stability, but its validity has mainly been examined in plant communities. Here, we investigate how ‘fast–slow’ trait composition, together with species richness and environmental factors, regulate avian community stability at a continental scale. We used bird population records from the North American Breeding Bird Survey during 1988–2017 and defined avian community stability as the temporal invariability of total community biomass. We calculated species richness and the community–weighted mean (CWM) and functional diversity (FD) of four key life-history traits, including body size, nestling period (i.e. period of egg incubation and young bird fledging), life span and clutch size (i.e. annual total number of eggs). Environmental factors included temperature, precipitation and leaf area index (LAI). Our analyses showed that avian community stability was mainly driven by the CWM of the ‘fast–slow’ trait. Communities dominated by ‘fast’ species (i.e. species with small body size, short nestling period and life span and large clutch size) were more stable than those dominated by ‘slow’ species (i.e. species with large body size, long nestling period and life span and small clutch size). Species richness and the FD of the ‘fast–slow’ trait explained much smaller proportions of variation in avian community stability. Temperature had direct positive effects on avian community stability, while precipitation and leaf area index affected community stability indirectly by influencing species richness and trait composition. Our study demonstrates that composition of ‘fast–slow’ traits is the major biotic driver of avian community stability over North America. Temperature is the most important abiotic factor, but its effect is weaker than that of the ‘fast–slow’ trait. An integrated framework combining ‘fast–slow’ trait composition and temperature is needed to understand the response of avian communities in a changing environment. A free Plain Language Summary can be found within the Supporting Information of this article.

Cellular automata (CA)-based models have been extensively used in urban expansion modeling because of their simplicity, flexibility and intuitiveness. Previous studies on CA-based urban growth mode...

Simple Summary The Wolong National Nature Reserve in Sichuan province covers a unique mountainous ecosystem located on the eastern border of the Tibetan Plateau in China. We applied a popular non-invasive observational method, i.e., infrared-triggered camera trapping, to gain thousands of photographs of wildlife to monitor biodiversity over three years. Combined with data on the local abiotic factors, our integrative statistical analysis identified the key environmental drivers, i.e., temperature and vegetation, affecting the distribution and abundance of mammals and birds in the reserve. All species were classified into three main types by their tolerance of or fondness for different environmental conditions. The detectability of each species by camera trapping was quantified and ranked to provide insights on each species' relative abundance in the area. The high-altitude ecosystem of the Tibetan Plateau in China is a biodiversity hotspot that provides unique habitats for endemic and relict species along an altitudinal gradient at the eastern edge. Acquiring biodiversity information in this area, where the average altitude is over 4000 m, has been difficult but has been aided by recent developments in non-invasive technology, including infrared-triggered camera trapping. We used camera trapping to acquire a substantial number of photographic wildlife records in Wolong National Nature Reserve, Sichuan, China, from 2013 to 2016. We collected information of the habitat surrounding the observation sites, resulting in a dataset covering 37 species and 12 environmental factors. We performed a multivariate statistical analysis to discern the dominant environmental factors and cluster the mammals and birds of the ecosystem in order to examine environmental factors contributing to the species' relative abundance. Species were generalized into three main types, i.e., cold-resistant, phyllophilic, and thermophilic, according to the identified key environmental drivers (i.e., temperature and vegetation) for their abundances. The mammal species with the highest relative abundance were bharal (Pseudois nayaur), Moupin pika (Ochotona thibetana), and Himalayan marmot (Marmota himalayana). The bird species with highest relative abundance were snow partridge (Lerwa lerwa), plain mountain finch (Leucosticte nemoricola), Chinese monal (Lophophorus lhuysii), and alpine accentor (Prunella collaris).

Dwarf mistletoe (Arceuthobium spp.,Viscaceae) (DM), a hemiparasitic plant, is nutritionally dependent upon its host tree and causes tree mortality in forests worldwide. Dwarf mistletoe infection results in physiological changes in the host, eventually causing the death of the host tree. In this study, we evaluated the changes in leaf reflectance of spruce trees, Picea crassifolia, infected by DM (Arceuthobium sichuanense) with ground‐based hyperspectral technology. A total of 112 sample sites were selected for analysis in the eastern part of Qinghai Province, China, including healthy spruce tree, light DM‐infected spruce tree, moderate DM‐infected spruce tree and high DM‐infected spruce tree in each site. The results showed that leaf reflectance was significantly different among healthy spruce, DM‐infected spruce, DM and dead spruce in the near‐infrared regions ranging from ~750 to 900 nm. Dwarf mistletoe infection resulted in the increase of leaf reflectance of host tree, and the intensity of DM infection was positively related to reflectance. However, five selected hyperspectral indices that commonly used to estimate the physiological status of plants (carotenoid reflectance index, photochemical reflectance index, normalized difference vegetation index, structure‐insensitive pigment index and water index) were not linearly correlated with the intensity of DM infection. Collectively, the hyperspectral characteristics of spruce infected by DM can be potentially used to detect DM‐induced changes on a landscape scale with satellite remote sensing, which can be used as an efficient advanced tool for DM disease monitoring.

The development of porous carbon materials from sustainable natural sources is an attractive topic in the field of energy storage materials. This study proposed the production of nitrogen-doped porous carbon (NPC) materials from the renewable cellulose nanocrystal (CNC) as carbon source and water-soluble urea as nitrogen source without any external activation. The liquid compounding treatment and subsequent carbonization provided the NPC materials a uniform and stable N-doping (7.4% nitrogen content), high specific surface area (366.5 m2/g) and various superior electrochemical properties. The fabricated NPC sample (CU-3, with the weight ratio of 1:10 for CNC and urea) exhibited a high specific capacitance of 570.6 F/g at a current density load of 1 A/g and good cycling stability (91.2% capacitance retention after 1000 cycles at a current density of 10 A/g) in the 6 M KOH electrolyte. Applying this NPC material as the electrode component in the assembled symmetric supercapacitor demonstrated the promising electrochemical stability with the specific capacitances of 88.2 F/g at the current density of 1 A/g and capacitance retention of 99.8% after 5000 cycles. The developed N-doped porous carbon material from CNCs and urea is expected to be a sustainable electrode component for the supercapacitor materials.

The parasitic plant dwarf mistletoe (Arceuthobium) is currently one of the most threatening infestations of coniferous forests worldwide, especially in Eurasia and North America, but its population dynamics in relation to one of its hosts (spruce) remain unclear. Here, toward understanding the population dynamics, differential equations were used to construct a life history model for the two populations, and two relatively independent subsystems, host and parasite, were generated from their symbiotic relationships. A suspected-infection model was used to couple them. The resulting models were used to analyze structural changes in the forest. When each infected spruce was assumed to support 1000 parasite shoots, the spruce population first increased rapidly, then slows. When 2000 parasite shoots were assumed, the forest declined dramatically, slipping to zero in the 10th year, and the spruce seedlings were unable to regenerate. Parasite shoot population curves transformed from exponential J-shapes to logistic S-shapes, reaching population limitations as germination rates changed. These results provide important clues to understanding developmental trends of the present parasite population and will assist in reconstructing invasion histories.

Land-climate interactions are driven by causal relations that are difficult to ascertain given the complexity and high dimensionality of the systems. Many methods of statistical and mechanistic models exist to identify and quantify the causality in such highly-interacting systems. Recent advances in remote sensing development allowed people to investigate the land-climate interaction with spatially and temporally continuous data. In this study, we present a new approach to measure how climatic factors interact with each other under land cover change. The quantification method is based on the correlation analysis of the different order derivatives, with the canonical mathematical definitions developed from the theories of system dynamics and practices of the macroscopic observations. We examined the causal relationship between the interacting variables on both spatial and temporal dimensions based on macroscopic observations of land cover change and surface climatic factors through a comparative study in the different grassland ecosystems of China. The results suggested that the interaction of land-climate could be used to explain the temporal lag effect in the comparison of the three grassland ecosystems. Significant spatial correlations between the vegetation and the climatic factors confirmed feedback mechanisms described in the theories of eco-climatology, while the uncertain temporal synchronicity reflects the causality among the key indicators. This has been rarely addressed before. Our research show that spatial correlations and the temporal synchronicity among key indicators of the land surface and climatic factors can be explained by a novel method of causality quantification using derivative analysis.

Sloping terrain of forests is an overlooked factor in many models simulating the canopy bidirectional reflectance distribution function, which limits the estimation accuracy of forest vertical structure parameters (e.g., forest height). The primary objective of this study was to predict forest height on sloping terrain over large areas with the Geometric-Optical Model for Sloping Terrains (GOST) using airborne Light Detection and Ranging (LiDAR) data and Landsat 7 imagery in the western Greater Khingan Mountains of China. The Sequential Maximum Angle Convex Cone (SMACC) algorithm was used to generate image endmembers and corresponding abundances in Landsat imagery. Then, LiDAR-derived forest metrics, topographical factors and SMACC abundances were used to calibrate and validate the GOST, which aimed to accurately decompose the SMACC mixed forest pixels into sunlit crown, sunlit background and shade components. Finally, the forest height of the study area was retrieved based on a back-propagation neural network and a look-up table. Results showed good performance for coniferous forests on all slopes and at all aspects, with significant coefficients of determination above 0.70 and root mean square errors (RMSEs) between 0.50 m and 1.00 m based on ground observed validation data. Higher RMSEs were found in areas with forest heights below 5 m and above 17 m. For 90% of the forested area, the average RMSE was 3.58 m. Our study demonstrates the tremendous potential of the GOST for quantitative mapping of forest height on sloping terrains with multispectral and LiDAR inputs.

Conserving and protecting the arid grassland ecosystem in Inner Mongolia under climate change requires large-scale observation and analysis. The interaction between land use/cover change (LUCC) and the regional climate change in this study area is addressed using macroscopic monitoring with remote sensing observation and analysis. The area’s LUCC was examined to demonstrate the structural dynamics of the land surface in the past from 1988 to 2011. The results of LUCC showed that agricultural land, high coverage grassland, and low coverage grassland were the dominant land cover types taking approximately 65.3% in total. Developed land constantly increased from 1.4% to 12.7% during the study period due to rapid urbanization in the area. According to the land surface energy balance equations, the four key variables of the regional climate system, (1) normalized difference vegetation index (NDVI), (2) albedo (α), (3) surface temperature (T s ), and (4) evapotranspiration (ET), were calculated for their spatial-temporal pattern dynamic and also to perform a correlation analysis to explore the structure-function relationship in the land-atmosphere interaction. The results illustrated that vegetation degradation caused an increase in albedo by approximately 5% on average by 2007 as attributed to the cumulative effects of the drought since 2003. ET also declined to around 0.8 cm/day in 2007. The correlation analysis results suggested the human land use such as development and agricultural activities made the surface boundary layer less responsive in the land-atmosphere interaction.

Urbanization changes the land surface environment, which alters the regional climate system. In this study, we took the Haihe River Basin in China as a case study area, as it is highly populated and experienced rapid urbanization from 2000–2015. We investigated how land use and cover change (LUCC) was driven by urban land development affects land-climate dynamics. From 2000–2015, we collected data from the land use and cover database, the remote sensing database of the Moderate Resolution Imaging Spectroradiometer (MODIS) series, and the meteorological database to process and generate regional datasets for LUCC maps. We organized data by years aligned with the selected indicators of land surface, normalized difference vegetation index (NDVI), albedo, and land surface temperature (LST), as well as of regional climate, cloud water content (CWC), and precipitation (P). The assembled datasets were processed to perform statistical analysis and conduct structural equation modelling (SEM). Based on eco-climatology principles and the biophysical process in the land-climate dynamics, we made assumptions on how the indicators connected to each other. Moreover, we testified and quantified them in SEM. LUCC results found that from 2000–2015 the urban area proportion increased by 214% (2.20–6.91%), while the agricultural land decreased by 7.2% (53.05–49.25%) and the forest increased by 4.3% (10.02–10.45%), respectively. This demonstrated how cropland intensification and afforestation happened in the urbanizing basin. SEM results showed that the forest had both positive and negative effects on the regional hydrological cycle. The agricultural land, grassland, and shrub had indirect effects on the P via different biophysical functions of LST. The overall effects of urbanization on regional precipitation was positive (pathway correlation coefficient = 0.25). The interpretation of how urbanization drives LUCC and alters regional climate were herein discussed in different aspects of socioeconomic development, biophysical processes, and urbanization-related atmospheric effects. We provided suggestions for further possible research on monitoring and assessment, putting forth recommendations to advance sustainability via land planning and management, including agricultural land conservation, paying more attention to the quality growth of forest rather than the merely area expansion, integrating the interdisciplinary approach, and assessing climatic risk for extreme precipitation and urban flooding.

Land degradation neutrality (LDN) has been widely recognized as an important target to achieve goals for global sustainable development. Ecological restoration projects (ERPs) are considered a traditional approach to mitigate wind erosion by altering the structures and functions of the ecosystem. Thus, the efficiency of China's historical large-scale ERPs for wind erosion mitigation should be examined and optimized to better address this global environmental challenge. We assessed the change in wind erosion using a biophysical model and investigated the associated drivers identified. In addition, the efficiency of ERPs was examined by adopting the theory of non-linear ecosystem dynamics. The erosion modulus significantly declined from 1990 to 2017, but this declining trend reversed since 2009. The structural equation model and related analyses revealed that the declining wind speed, wetting soil moisture, and vegetation greening substantially reduced wind erosion, while the reversal of declining wind speed around 2009 aggravated wind erosion, particularly in the northern Inner Mongolia Sandstorm Area. The relatively arid climate restricted vegetation restoration and further offset afforestation efforts, resulting in the transition of declining erosion modulus. From the perspective of non-linear ecosystem dynamics, a wet climate provides a crucial window of opportunity for ERP in drylands, while the window of risks due to dry and windy climates may extend the time required for a shift change after ERP and may postpone the stage change toward the LDN goal. Hence, climate-induced windows of opportunity and risks are crucial in identifying the time for initiating ERPs, and existing environmental conditions and critical thresholds should be carefully considered.

Topsoil erosion is a widespread and major threat to terrestrial ecosystems that leads to environmental deterioration. Monitoring soil erosion dynamics and understanding the driving mechanisms are of great significance for optimizing ecological restoration programs and combating land degradation. We apply a widely used soil erosion assessment model to quantify the changes in soil erosion on the Loess Plateau (LP) in response to afforestation-induced vegetation cover and land use/cover changes. Furthermore, we examine the relationship between landscape metrics and soil erosion using spatial econometric approach. The results indicate that soil erosion in the LP substantially decreased through afforestation efforts, while the observed sediment load declined significantly as a result of soil and water conservation programs. A number of largescale ecological programs altered the spatial configuration and structural composition of the landscape from different aspects, which disturbed the formation and transportation of soil erosion, eventually resulting in a reduction in soil loss. The spatial association between landscape metrics and soil erosion indicated that properly fragmented landscapes can effectively decrease soil erosion. Due to the spatial spillover, soil erosion in one county can be affected by soil erosion in adjacent counties. Therefore, the spillover effect between counties should not be ignored, and the responsibility for formulating and implementing solutions to combat land degradation should not fall solely on individual local governments. Preferably, the cooperation between different regions should be strengthened as a critical way to improve the efficiency of programs combating land degradation.

In the acceleration of industrialization and urbanization, brownfield is an important resource for land regeneration and restoration targeting to recover its ecosystem function. Landfills, as a type of brownfield distributed in the highly populated areas, occupy massive land resources. The ecological restoration of landfills becomes an engineering approach to achieve multiple effects of society, environment, and economy. This paper aims to monitor and assess the restoration microclimatic effects of landfills restoration in China with remote sensing data and techniques. We selected representative landfill restoration projects, including Nanhaizi Park in Beijing, Nanhu Park in Tangshan, and Tianziling Park in Hangzhou, as the study cases. Using the Landsat imagery, the scenes of the pre-restoration, mid-restoration, and post-restoration were retrieved, and the surface energy balance equation was applied to calculate normalized difference vegetation index (NDVI), land surface temperature (Ts), and evapotranspiration (ET), representing vegetation conditions and hydro-heat microclimate conditions. The study areas are divided into four subzones and extracted the calculated values for statistics and comparison. We defined an indicator of restoration intensity (RI) using the different subzones to the outer contour distance radius and restoration phases to evaluate the spatial-temporal restoration degrees. The spatial pattern dynamics was displayed in the urbanization context in the cases of Beijing and Tangshan. We examined and quantified the relations between RI and the key indicators, NDVI, Ts, and ET. The overall results revealed that with higher restoration intensity, NDVI and ET became higher, and Ts became lower. It suggested that the ecological restoration on the landfills brought better vegetation, cooling, and humidification effects for the microclimatic environment. Our research has the implications for monitoring and assessing the climatic effects of ecological restoration in the brownfield regeneration in a macroscopic and ecosystem perspective.

A new molecularly imprinted SiO2 (MISiO2) film on the surface of indium tin oxide (ITO) electrode was prepared by the sol-gel method and was then applied successfully in the electrochemical chiral recognition of tryptophan (Trp) isomers. Owing to the high chemical stability, excellent rigidity, and low cost, the resultant sol-gel SiO2 is a good matrix material for molecular imprinting. Nonionic surfactant cicosaethylene glycol hexadecyl ether (Brij58) arranged directionally on the surface of the hydrophobic ITO electrode possesses a large amount of oxygen-containing functional groups and may induce the accumulation of template molecules (L-Trp) on the surface of ITO, resulting in L-MISiO2/ITO after the removal of L-Trp templates by calcination. The characterizations of the L-MISiO2/ITO reveal that the L-Trp templates could be successfully removed from the matrix, producing complementary cavities within the L-MISiO2/ITO. The resultant L-MISiO2/ITO exhibits greatly higher affinity toward L-Trp than D-Trp due to the three-point interaction mechanism, and therefore it exhibits good chiral recognition ability for the Trp isomers. In addition, the as-prepared L-MISiO2/ITO or D-MISiO2/ITO (D-Trp as the templates) can predict the ratio of L- and D-isomers in racemic mixture. Last, the MISiO2 films exhibited quick binding kinetics and good recognition reproducibility.

Full-duplex systems are expected to achieve 100% rate improvement over half-duplex systems if the self-interference signal can be significantly mitigated. In this paper, we propose the first full-duplex system utilizing multireconfigurable antenna (MRA) with ∼90% rate improvement compared with half-duplex systems. MRA is a dynamically reconfigurable antenna structure that is capable of changing its properties according to certain input configurations. A comprehensive experimental analysis is conducted to characterize the system performance in typical indoor environments. The experiments are performed using a fabricated MRA that has 4096 configurable radiation patterns. The achieved MRA-based passive self-interference suppression is investigated, with detailed analysis for the MRA training overhead. In addition, a heuristic-based approach is proposed to reduce the MRA training overhead. The results show that at 1% training overhead, a total of 95 dB self-interference cancelation is achieved in typical indoor environments. The 95-dB self-interference cancellation is experimentally shown to be sufficient for 90% full-duplex rate improvement compared with half-duplex systems.

The source region of the Yellow River, China, experienced degradation during the 1980s and 1990s, but effective ecological restoration projects have restored the alpine grassland ecosystem. The local government has taken action to restore the grassland area since 1996. Remote sensing monitoring results show an initial restoration of this alpine grassland ecosystem with the structural transformation of land cover from 2000 to 2009 as low- and high-coverage grassland recovered. From 2000 to 2009, the low-coverage grassland area expanded by over 25% and the bare soil area decreased by approximately 15%. To examine the relationship between ecological structure and function, surface temperature (Ts) and evapotranspiration (ET) levels were estimated to study the dynamics of the hydro-heat pattern. The results show a turning point in approximately the year 2000 from a declining ET to a rising ET, eventually reaching the 1990 level of approximately 1.5 cm/day. We conclude that grassland coverage expansion has improved the regional hydrologic cycle as a consequence of ecological restoration. Thus, we suggest that long-term restoration and monitoring efforts would help maintain the climatic adjustment functions of this alpine grassland ecosystem.

De-icing salt contamination of urban soil and greenspace has been a common issue of concern in many countries for years. In the 2009/2010 winter, Beijing experienced a contamination accident resulting from the overuse of de-icing salt, reported as almost 30000 tons, which severely damaged urban vegetation alongside roadways. The methods of sampling and rating for both soil contamination and response of the plant populations were developed to rapidly assess this emergency environmental event. Results showed that the shrubs were more severely damaged than the arbors in terms of both degree and extent, as almost all of the surveyed shrubs were severely damaged from the salt contamination, while only about 1/4 of the recorded arbors were rated as “severely injured” according to the integral plant injury index. The rating of the injury level showed that the trees like Pinus bungeana, Sophora japonica, and the shrubs like Euonymus japonicus, Sabina vulgaris showed less tolerance to de-icing salt pollution. The patterns of vegetation damage demonstrated that the ever-green shrubs alongside roads and the deciduous arbors in the center of roads were most vulnerable to the salt damage.

The source region of the Yellow River is located in the eastern of Tibetan Plateau at an altitude of 3900–5300 m. Applying the method of unsupervised classification, ISODATA, we defined the land covers of the region into five types, snow cover, water body, bare soil, low coverage grassland, and middle-and-high coverage grassland. To learn the pattern of evapotranspiration ( ET ) at large scale is essential for the local water use and management. With surface energy balance algorithm for land (SEBAL), we retrieved ET and the energy fluxes with Landsat 5 remote sensing images of the area in the summer of 2006. It was estimated that the instantaneous evapotranspiration was highest in middle-and-high coverage grassland of the southern region at 0.31 mm/h on average level, and lowest in bare soil of the northern region at 0.13 mm/h on average level. The key variables in SEBAL model, including the normalized difference vegetation index, surface albedo, the surface radiation temperature, net radiation, and sensible heat fluxes were calculated and illustrated to see their patterns in the region. At final, based on the correlation analysis among the key variables, we conducted a conceptual framework of cause–effect loops involving the main factors in the process of ET . Under the framework, we described the typical situations of hydro-heat in the source region.

This study was conducted to investigate the dynamic changes of bulk soil and microbial populations in the surrounding plant rhizosphere under the influence of chloride de-icing salt. Each experimental plant was given 0.25 L de-icing salt solution with an irrigation concentration of 200 g/L, once every 3 days for 27 days. Samples were taken weekly from each soil layers (0–15 cm, 15–30 cm and 30–45 cm). The results revealed that de-icing salt led to different effects in different soil layers in one month. A trend of increasing electric conductivity (EC) values, Na+ concentrations, and Cl− concentrations in the upper soil layer, compared with the other two soil layers, was apparent, which proved a stronger effect of de-icing salt on the upper soil layer. Soil cation exchange capacity (CEC) decreased with the accumulation of the de-icing salt. Denaturing gradient gel electrophoresis (DGGE) analysis indicated that de-icing salt decreased the Shannon diversity (H) and Evenness (E) of fungal populations in three soil layers and led to a decrease of bacterial H in the upper soil layers. However, a contrary trend for H and E of bacterial populations was seen in the middle and lower soil layers. Both the unweighted pair group mean average (UPGMA) cluster and canonical correspondence analysis (CCA) analysis indicated that the bacterial populations were more stable than the fungal populations in response to salinity stress. CCA analysis showed the dynamic changes of microbial populations and the soil properties (EC, CEC, Na+ and Cl−) were strongly correlative. The microbial populations were obtaining a new dynamic equilibrium at the end of the study. The dominant microbial populations were originally Crepidotus, Metarhizium, Penicillium and Acidobacterium, but converted to Pythium, Boletaceae, Cystofilobasidiales, Phacidium, Acidobacterium, Pseudomonas and Chloroflexi with the addition of de-icing salt. The obtained results suggest that the uses of chemical agents leading to soil salinization, such as de-icing salt, can destroy the micro-ecosystem of bulk soil surrounding plant rhizosphere and influence soil health.

In order to prevent severe pollution by de-icing salt on greenery along urban roads, a half lethal dose (LD50) for a plant population was confirmed through stress simulation of chloride de-icing salt on Euonymus japonicus, with an analysis of physiological changes, statistics on mortality rate on plant populations and mathematic modeling during a 30-day subacute toxicity test. The results indicate that a significant positive correlation in the early stages and a significant negative correlation in the later stages were observed between the amount of chlorophyll a and b in plants and a cumulative dose of de-icing salt. The amounts of free proline in plants and the dose of de-icing salt were positively correlated over the entire period. No significant correlation in the initial stage, but a significant negative correlation in later stages was observed between the soluble protein and the dose of de-icing salt. LD50 of this chloride agent on E. japonicus is 5 kg·(L·m2)−1 over 30 days.

The hydropower capacity of China ranks first in the world and accounts for approximately 20% of the total energy production in the country. While hydropower has substantially contributed to meeting China's renewable energy targets and providing clean energy to rural areas, the development of hydropower in China has been met with significant controversy. Ecologically, hydro projects alter the landscape, with potential impacts to the country's aquatic biodiversity. Over the past four decades in China, various mainstream opinions and misunderstandings have been presented concerning how to alleviate the negative impacts of hydro projects on aquatic ecosystems. This article reviews research concerning potential mitigation measures to enhance aquatic biodiversity conservation in hydro projects in China. Based on the academic attention such research has attracted, three technical measures for aquatic biodiversity conservation are considered: (1) fish passages, (2) restocking efforts and (3) river and lake renovations. This article provides a historical comparison of these three practices in China to demonstrate the advantages and disadvantages of each method. The article also reviews the relevant legislation, regulations and technical guidelines concerning China's hydro projects dating back to 1979. The dynamics in research, publications, and patents concerning these three mitigation measures are summarized to demonstrate their technological developments in the context of legislative and policy advances. Data were gathered through the China Knowledge Resource Integrated Database and the State Intellectual Property Office of the People's Republic of China. Based on the analysis provided, the article recommends an expansion of China's environmental certification system for hydro projects, more robust regional legislation to bolster the national framework, the cooperation between upstream and downstream conservation mechanisms, and better monitoring to determine the efficacy of mitigation measures. Keywords: Biodiversity conservation, China, Hydropower, Policy, Research