Guangdong has the longest coastline of all provinces in China, with many coastal wetland types. However, long term waterbird observation, which is crucial for wetland conservation, has only been carried out in a few sites. To understand the wetland bird diversity patterns of the Guangdong coast, identify the main ecological environment problems and assess the ecosystem stability, surveys were conducted every winter between 2016-2019 at Leizhou Bay and Shantou coastal wetlands. Species-level, functional and phylogenetic diversities were analyzed separately. After three years of observation, a total of 96 048 waterbird individuals belonging to 63 species, 10 families and 6 orders were recorded. Among them, the wintering waterbirds in Shantou consisted of members of the Charadriiformes, Anseriformes and Ciconiiformes, while members of the Charadriiformes dominated in Leizhou Bay. There was no significant difference in species diversity between the two sites. Though, no significant difference was observed in functional evenness of traits for body mass, feeding guild and foraging location, functional divergence of these traits were significantly higher in Shantou than in Leizhou Bay. Two phylogenetic diversity indices including mean pairwise distance and mean nearest taxon distance all shown significant difference between the two sites. The results of the phylogenetic diversity analysis show the waterbird assemblages in Leizhou Bay were mainly structured by environmental filtering, which were phylogenetically clustered (SES.MPD<0). In contrast, asemblages in Shantou were phylogenetically overdispersed (SES.MPD>0), showing some interspecific competition in this area. The result indicates that the differences of functional traits and phylogenetic structures were driven by local geographical location, habitat composition, human disturbance and other environmental factors. Corresponding protection measures and ecological restoration strategies should be developed according to the characteristics of the respective waterbird assemblages.

Recently, coastal wetlands have been facing threats resulting from land reclamation, which is performed to alleviate land pressure and generate a series of economic benefits in response to increasing human population size and rapid urbanization. As a result, coastal wetlands are undergoing devastating exploitation on a global scale, with coastal reclamation being most prevalent in Europe and Asia. Because of their sensitivity to environmental change, waterbirds are often used as indicator species for estimating the ecological health of coastal wetlands. Lianyungang City is located on the East Asian-Australasian Flyway, and is an important stopover and wintering site for waterbirds. In the winters of 2016-2018, the community structure and diversity of wintering waterbirds in the Linhong, Qingkou, Xingzhuang and Liezi estuaries were surveyed. A total of 47 waterbird species from 8 families and 12 orders were found in the four estuaries. There were 37 wintering species, 5 resident species and 5 passing migrant species, of which one was listed as a first-class protected species in China. Wintering populations of five species in a single survey exceeded 1% of their global populations. The number of species and individuals varied between years; both were highest in 2017, with the lowest species count in 2016 and the lowest individual count in 2018. The Shannon-Wiener diversity index and evenness index were highest in 2017, while the dominance index was highest in 2016. Moreover, there were no significant differences in the number of species or the diversity index between the four estuaries, but there were significant differences in density and population size (all P<0.001). There was high similarity in species composition between the four estuaries (similarity index ≥ 0.600), of which the similarity between Xingzhuang and Liezi estuaries was highest (0.714). The results show that the Lianyungang coastal wetlands are important wintering sites for waterbirds, and that the diversity of waterbirds in different estuaries was affected by reclamation, development and habitat change in their respective regional environments. It is concluded that waterbird monitoring should be increased for the ecological protection of the East Asian-Australasian Flyway.

Megacities (or metropolises) have diverse urbanization gradients, and are typical research sites to study the relationships between human disturbance and biodiversity. During the urbanization process in Shanghai, urban greenspaces and farmlands become the dominant ecosystems, altering terrestrial bird communities. This study selected three typical forest parks (Binjiang, Haiwan, and Sheshan) and three farmlands in Chongming (Chenjiazhen, Gangxizhen, and Miaozhen) as research sites to assess the effects of human disturbance on community stability of terrestrial breeding birds. The results show that the community structure of terrestrial breeding birds in greenspaces and farmlands in Shanghai was stable from 2016 to 2018. The density of breeding birds increased steadily during the study period. Greenspaces have significant lower density of terrestrial breeding birds than farmlands. Nine groups of bird guilds have different distribution patterns between greenspaces and agricultural ecosystems. Variability index of breeding bird communities is positively related to the intensity of human disturbance. Omnivorous birds are more tolerant of human disturbance than other guilds. Bird diversity could be increased effectively by improving local habitats of urban parks and changing production patterns.

From October 2017 to May 2019, the population characteristics, activity range, time budget and behavioral rhythm of the common crane (Grus grus) in the basin of Muzati River in Baicheng County, Aksu Prefecture were investigated and analyzed through the direct counting method, scan-sampling technique, satellite tracking and the minimum convex polygon. The population number of common cranes was more than 4 700 in 2009, more than double that of 2016. And the population development dynamics showed an upward trend. The group characteristics of common cranes are main family groups (63.90%), followed by aggregation groups (28.62%), and the least for solitary crane (7.48%). The family group is mainly composed of 2 adults and 1 child (46.82%), and the aggregation group is dominated by 5-8 individuals (65.91%). In the whole wintering period (about 140-160 days), the total active distance of the common crane is 1 058 km, and the activity area is relatively fixed, with a total area of 125 km². The daily activity area and distance changed with the change of temperature: the daily activity range and distance decreased with the decrease of temperatures. On the contrary, it increased. Therefore, the activity area and distance changed in a concave shape, first increasing (October to November), then gradually decreasing (December to January), and then increasing (February to March). Feeding and alerting are the main wintering behaviors of common cranes. 46.8% of the time of the common crane were used for eating, and 17.8% of the time were used for alerting. The time spent on resting, locomotion, grooming and other behaviors was 13.4%, 11.4%, 7.4% and 3.2%, respectively. The peak of daily eating was double convex, which appeared at 8:00-9:00 and 17:00-18:00, reaching 57.0% and 58.5%, respectively. The peak of rest appeared at 11:00-15:00, accounting for 24.6%. The population of common cranes in this area is faced with many threats, such as grazing, farming, natural enemies, cold, road vehicles and artificial eviction.

Birds form an important animal group in all ecosystems. Birds are sensitive to environmental change, relatively easily surveyed and are frequently used as indicators for environmental monitoring and evaluation. In order to understand the relationships between bird diversity and the environment, it is important to conduct bird community research during the breeding season. Twice a year during May-July in 2016-2019, the fixed line transect method was used to monitor bird diversity at four different habitats in Tacheng City, Xinjiang. 22 line transects through four typical habitats were surveyed. During the observation period, 15 orders, 40 families and 115 species of bird were recorded. The number of species and the number of adults were highest in the Kulusitai Steppe (KS), the Taerbahatai Mts. Shrub (TMSH) and the Taerbahatai Mts. Steppe (TMST). The Emin River Valley Forest (ERVS) had the fewest. In the same habitat, the number of adults (F=4.183,P=0.017) and the density (H=5.004,P=0.008) of KS had significant annual differences. The species richness index and the Shannon-Wiener diversity index of TMSH and TMST were higher. The Pielou evenness index of ERVS and the Simpson dominance index of TMST were the highest. The similarity of bird communities in different habitats was in medium level (0.33-0.58). The proportion of insectivorous birds was high in all habitats. A wide variety of bird foraging guilds were observed, these were distributed rather evenly with a relatively greater variety in KS. In summary the unique geographical location and the abundant natural resources in Tacheng City provide good habitat and a healthy breeding environment for birds.

Bird diversity is an important indicator for biodiversity assessment and ecological environmental impact assessment. The researches on bird diversity in China have been abundant in recent years; however, the impact of bird diversity on biodiversity is equivocal. In this study, the reasons for fluctuations on bird diversity components in Liaoning Province were investigated. Birds were counted twice around 6 sites during the breeding season for 8 consecutive years. A total of 10 fixed sample lines with a length of 3 km and 23 fixed sample points were set up. Through 8-year study, 202 622 birds of 178 species were recorded, belonging to 50 families, 17 orders. The dominant species and most common species were mainly waterbirds. 70 species were summer migrants, 47 were travelers and 47 were residents. A total of 3 first-class and 16 second-class of national protected birds were recorded. Among the 6 studied sites, 4 diversity parameters of Laotuding showed the smallest fluctuations, while Liaohekou and Huanzidong had relatively large diversity fluctuations. In general, bird diversity in woodland is relatively stable, while the wetland bird species diversity fluctuates probably due to the rapid destruction and reconstruction of related habitat.

Bird Diversity in Yumen was investigated using the line transect method from April 2013 to June 2019. A total of 97 bird species were recorded that belong to 36 families and 17 orders. Among the 97 species, 1 species was a first-class national protected bird and 10 were second-class national protected bird in China. Among the settlements, summer migrants(53) and resident species (23) were dominating, and accounted for 54.64% and 23.71% of the observed species, respectively. Bird composition in settlements varied slightly by year (F_{2, 20}=1.358, P=0.296). Among the four habitats, the bird species diversity in wetland habitats was the highest, and the bird species diversity in village habitats was the lowest. The similarity index between farm forest and village habitats was the highest, whereas that between wetland and village habitats was the lowest. The diversity index and evenness index of birds in wetland and desert habitats were significantly different from those in other habitats (P<0.05), but the diversity and evenness index of birds in farmland and open forest were not significantly different from those in villages (P=0.065). The correlation analysis show that there was no significant correlation between average precipitation from April to May and bird diversity index (r=0.02, P>0.05), but there was a significant positive correlation between average temperature from April to May and bird diversity index (r=0.879, P<0.05). The change in the bird community in Yumen during the reproductive period was generally stable and there was little fluctuation during these years.

An investigation was conducted on the community structure and diversity of reproductive birds in Luqu County, Gansu Province in May and June from 2016 to 2019 using line transects. There were 125 species belonging to 38 families and 15 orders of all the recorded birds including 56 resident species, 51 summer visitors, 14 species of migrants and 4 species of winter visitors. Among them, 3 species of birds are under the first-grade state protection and 6 species of birds are under the second-grade state protection. According to the zoogeographic fauna of China, the avian distribution pattern of breeding birds in Luqu County is mainly composed of Palaearctic birds, but there were also Oriental birds. The distribution patterns that included more species were the Palaearctic type (23 species), Himalaya-Hengduan Mountain type (18 species), widespread species (13 species), Holarctic type (17 species), Highland type (12 species) and Oriental species (10 species). This result is related to Luqu's location on the transitional zone between the Oriental and Palaearctic realms, which also reflects the faunal characteristics of Luqu belonging to the Qinghai-South Tibet subregion of the Qinghai-Tibet Plateau region, Palaearctic realm. Among the different communities, the number of species was the highest in meadows (71 species) and forests (61 species), whereas the river habitats had the lowest number of species (39 species). The highest Shannon-Wiener diversity index was found in forests followed by lakes and shrubs. Additionally, the highest Simpson diversity index was observed in lakes, followed by forests and shrubs. The G-F index show that birds in the entire survey area had a high diversity at the family or genus level from 2016 to 2019. To protect the bird diversity of Luqu County, stronger protection is needed for the Gahai Lake wetland ecosystem and Zecha forest ecosystem.

As a significant component of the biosphere, aves play an important role in maintaining ecosystem balance. Tianzhu County is located in the northeast edge of the Qinghai-Tibet Plateau. The diverse vegetation provides a variety of habitats for birds. An investigation was carried out on the diversity of breeding birds in Xiama Forest Farm, Tianzhu County, Gansu Province, in June and July from 2014 to 2019 using the line transect method. 77 bird species that belonged to 26 families and 8 orders were recorded; of these species, 48 were residents and 29 were summer visitors. Among them, one species was listed in the first category and seven species were listed in the second category of the Chinese State Key Protected Wildlife List. Additionally, there were one vulnerable species in the Red List of China's vertebrates. The number of bird species varied among different years, but not significantly. Shannon-Wiener diversity index and evenness revealed that the community structure of birds in different habitats was highest in woodland habitats (59 species, 3.940 58, 0.694 69, respectively), and lowest in alpine littoral habitats (9 species, 2.598 06, 0.458 02, respectively). Moreover, a general linear mixed model was used to analyze bird richness and abundance in different habitats and at different altitudes in Xiama. The results show that there were significant differences in bird abundance among different habitat types, and bird species richness significantly decreased with increasing elevation. With continuous destruction of the ecological environment by human activities, the quality and area of bird habitats are adversely affected. Bird detection and protection have a long way to go.

By using line- and point-sampling methods, bird surveys were conducted at Guyuan County, Hebei Province in June and July of each year from 2016 to 2019. A total of 28 401 individuals were recorded, which belong to 138 species, 40 families and 15 orders. Of them, the birds of Passeriformes were the major components of the avian community, for a total of 20 049 individuals, 66 species and 21 families; 57 species (41.30%) were summer breeders and 42 species (30.43%) were transient migrants; Eastern spot-billed duck (Anas zonorhyncha) and chestnut-eared bunting (Emberiza fucata) were the dominant species of the avian community. According to their endangered status, 1 species was under first-grade state protection, 7 species under second-grade state protection, and 108 bird species were the national protected terrestrial wild animals with important ecological, economic and scientific values in China; There were 1, 2, and 5 species listed as endangered, vulnerable and near threatened species by IUCN respectively. In different habitats, deciduous broad-leaved forest has the highest Shannon-Wiener diversity (H'=3.107); town has the highest Pielou evenness (J=0.808). According to the Sørensen similarity of bird community, herbaceous swamps have similar species composition with large lakes, but deciduous broad-leaved forests and urban habitats differed greatly; The circulating components of beta diversity in different habitats of avian community were significantly higher than the nested groups. These results suggest that deciduous broad-leaved forest, large lake and small lake have stable community structure and should be the focus of bird protection and human disturbance control.

Known as the "kidney of the earth", wetland is one of the most important living environments for human beings. On the basis of analyzing the concept of wetland ecological compensation, the policies and practices of wetland ecological compensation at domestic and abroad have been systematically sorted out, and the compensation carriers, methods, financing, standards, models and performance evaluation have been summarized. Moreover, the following main existing problems of wetland ecological compensation are proposed: theoretical research lags behind practice, system design is lacking, channels of compensation funds are relatively simple, compensation standards in different areas are significantly different, and the corresponding supervision and effectiveness evaluation mechanisms are seriously lacking. The priority research directions of wetland ecological compensation are prospected: (1) strengthening the theoretical research on wetland ecological compensation; (2) accelerating the study of wetland ecological compensation system; (3) expanding the pilot practice study on wetland protection; (4) strengthening the assessment of wetland ecological compensation supervision and compensation effectiveness. At the same time absorb and summarize the scientific and effective compensation models at domestic and abroad to promote the construction of market-oriented and diversified ecological protection compensation mechanisms in China at this stage. This study can provide scientific basis and decision-making reference for wetland ecological compensation and restoration.

Ecological security is a concept with rich connotations,which operates across multiple scales from ecosystems and regions to the globe. Understanding the relevant scales of ecological security is the foundation for effective research and the construction of a comprehensive ecological security system. Ecological security includes regionality, spatial differences and spatial spillovers. Each scale of ecological security has its own characteristics but all the scales are interconnected. Global scale ecological security concerns the overall survival and development of humanity. Regional scale ecological security is easier to address through policies or projects because it corresponds with governance units. The ecosystem is the most important scale to understand the fundamental mechanisms of ecological security. Ecological security at different scales is affected by both natural and social factors. The global and regional scales pay more attention to the impact of social factors, while the ecosystem scale focuses more on natural factors. The changing characteristics and functions of different ecological media result in ecological security issues at different scales. The differences in scales could have influences on the main analysis methods. Global scale ecological security assessment commonly applies models, while regional scale research uses comprehensive evaluation, ecological models and landscape ecology methods. At the ecosystem scale, the main methods are ecological indexes and ecosystem models.

Pesticides are applied at high frequency during rice cultivation, and drained into the surrounding water bodies periodically from paddy water. Therefore, pesticide pollution in rice production can cause potential risk to the surrounding surface water. Risk assessment for pesticides used in rice paddy could provide scientific basis for the decision-making of pesticides environmental safety management. Exposure assessment is the key step of risk assessment. The exposure assessment models for pesticides used in paddy fields were summarized in present researches, including RICEWQ, Tier I Rice and PFAM models of the United States, MED-RICE and SWAGW models of the European Union, Aquatic PEC, PADDY model series and PCPF model series of Japan, TOP-RICE and PRAESS models of China, respectively. The background of model development, the conceptual models, the calculation formulas, the input parameters, the output results, and the characteristics and application of models were introduced. Differences of these models were compared from the aspects of simulation level, prediction accuracy and simulation scale. Limitations of existing models have been analyzed. Lastly, key points of future researches are put forward, including to complete and improve the rice-surface water exposure scenario system, to strengthen the validation of models and the comparison of prediction results between different models, and to develop Large-scale watershed integrated simulation models.

In this study, the per capital ecological well-being and eco-economic efficiency models were firstly constructed on the basis of the improving ecological well-being accounting method by introducing the contribution rate of the ecosystem which was supported by the ecosystem service theory. Furthermore, ecological well-being zoning model was proposed from the perspective of relative justice and efficiency. And then the potential indexes of ecological well-being were calculated by using the above-mentioned models. Lastly, the temporal-spatial pattern of ecological well-being zone and ecological well-being potential were analyzed for 31 provinces of China from 2000 to 2015. The results show that: (1) There was significant difference among provinces about per capital ecological well-being and eco-economic efficiency during the study period. In some provinces, per capital ecological well-being was high while the eco-economic efficiency was low, and some provinces were on the contrary. (2) 31 provinces were divided into four groups by the differences in equity and efficiency of ecological well-being. The first group was for high efficiency-high well-being zones which first appeared in Hunan Province in 2015. The second group was for high efficiency-low well-being zones mainly distributed in the eastern and central provinces. The third group was for low efficiency-high well-being zones mainly distributed in the western provinces. And the fourth group was for low efficiency-low well-being zones scattering in Sichuan, Guangxi, Jiangxi and Hainan provinces in 2015. (3) There was a spatial negative correlation between relative well-being and relative efficiency through bivariate spatial autocorrelation analysis, the high-low clusters were mainly located in the western inlands and the low-high groups mainly in the eastern coastal provinces.

The ecological effects of land-use changes have emerged as a hot topic within research on global environmental changes. The findings of studies on changes in habitat quality resulting from land-use changes provide important basis for policy-making regarding ecological protection and land management. In this study, GIS technology was used in conjunction with the InVEST model to analyze remote sensing data compiled for the period 2005-2015 to assess changes in the quality of habitat in Bairin Right Banner in Inner Mongolia. The results of the analysis indicated that grassland, woodland, and farmland were the dominant types of land use in this region, accounting for more than 85% of the total land area. During the period 2005-2015, areas of wetland, construction land, and woodland increased by 335.01, 298.29, and 258.67 km², evidencing corresponding growth rates of 91.80%, 301.85%, and 12.07%, respectively. Conversely, the areas of farmland, grassland, and unused land decreased by 533.98, 279.28, and 78.71 km², with associated reduction rates of 28.34%, 5.63%, and 15.40%, respectively. In the decade, large areas of grassland, woodland, dryland, and sandy land had undergone conversion. Of these areas, 948.70 and 303.53 km² of dryland and sandy land, respectively, had been converted into land-use types of ecological importance (forestland, grassland, and wetland). The habitat quality index applied in the study show distinct spatial differentiation characteristics. Whereas areas of land of lower habitat quality were predominant in 2005, areas of land of higher habitat quality were predominant in 2010 and 2015. During this 10-year period, land areas with habitat quality of high, higher, and low grades in the index increased, with marked increases in areas with high-grade habitat quality (a change rate of 39.65%) and decreases in areas of lower-grade habitat quality (a change rate of 37.55%). The average habitat quality index increased from 0.457 to 0.528, indicating an improvement in the overall habitat quality in this region. Thus, the implementation of the project of returning farmland to forest and grassland has evidently been effective, contributing to ecological recovery in this region.

Twelve types of biochars were prepared by pyrolyzing rice husk and sawdust at different temperatures (200-700 ℃), which were referred as DBC200-DBC700 and MBC200-MBC700, respectively. The characteristics of these biochars and their Cu²⁺ adsorption performance were investigated, including the adsorption isotherms, kinetics and dynamic leaching. Results indicate that biochars derived from higher temperature showed better performance for Cu²⁺ adsorption, and those produced at 700 ℃ showed the highest sorption capability. The sawdust biochar had higher adsorption capacity than rice husk biochar derived under the same pyrolysis temperature. There was significant correlation between Cu²⁺ adsorption and each of the parameters, such as pH, specific surface area, carboxyl group content, and pore volume for rice husk biochars. For sawdust biochar, there was significant correlation between Cu²⁺ adsorption and the total acid groups, and obviously significant correlation between Cu²⁺ adsorption and pH as well as the carboxyl group content. Adsorption isotherms of Cu²⁺ by DBC700 and MBC700 were well fitting with Freundlich model, and the adsorption kinetics were greatly fitting to both pseudo-first-order model and pseudo-second-order model. The average amount of Cu²⁺ adsorption by DBC700 and MBC700 from dynamic adsorption experiment reached 7.58 and 16.12 mg·g^-1, respectively. The results indicate that rice husk and sawdust biochars could be used as efficient adsorbents to remove Cu²⁺ from wastewater.

Based on the investigating for the concentrations and vertical profiles of four heavy metals (Cu, Pb, Cr and Cd) in the sediments collected from the Dishui Lake and its diversion channels, ecological risk assessments were performed using the methods of land accumulation index and potential ecological risk index. Furthermore, the bioaccumulation characteristics and dietary risk resulted by consumption of the freshwater fish in the lake were analyzed. Finally, the sources of heavy metals in sediments were identified using multiple regression and principal component analysis. The results show that the concentrations of Cu and Cd in the surface sediments of the Dishui Lake area and the diversion channel were 1.3 time and 13.0 times higher than the background value of heavy metal Cu and Cd in Shanghai tidal flat, respectively. Among the concentrations of heavy metals in the lake sediments worldwide, the concentrations of Dishui Lake were at a low level. The results also show that the concentrations of heavy metals declined with increasing of depth vertically. Cd was found the main contributor to the heavy metal pollution in the sediments of the Dishui Lake. Although heavy metals in organisms did not pose significant food risks, attention should be paid to Cu and Cd due to their high bioaccumulation potentials. Finally, based on the source identification, Cu, Pb and Cr were mainly from similar origins of traffic activities, while Cd was primarily from agricultural activities.

To evaluate the impact of mining activity on heavy metals in a high-altitude freezing and thawing area in Xinjiang, soil, water and sediment at different sampling points were systematically evaluated. The results show that the average heavy-metal contents in the mining area were higher than that of the background of Xinjiang area and showed an accumulation trend in the soil. As, Cd, Cu, Pb, and Zn are the main heavy-metal pollutants caused by the mining activities. In general, the concentration of As and Cd gradually decreased as the elevation increased, while other elements generally showed gradual increasing trends; heavy metals were also accumulated in the tailings area. Results show that the enrichment of As, Cd, and Cu was mainly derived from mining activities, while the accumulation of Pb and Zn was mainly affected by the element dissolution of the tailings and emissions from the construction vehicles. The surface water quality in the assessment area was adequate and no heavy metal elements exceeded the standard. As, Pb and Cd were not accumulated in the sediment, but Zn, Cu, Ni and Cr were enriched. The Potential Ecological Risk Index (RI) and the Ground Accumulation Index analysis of the heavy-metal sediment indicate that some points of the tailing area of the mining area were moderately polluted and the heavy-metal contamination in the sediments was generally higher than that in the soil. Furthering the study on the migration and transformation of heavy-metal elements and environmental threshold in high-altitude and freezing mining areas can be significant in finding suitable ecological restoration measures.