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Quantitative study on effects of roads on suitable breeding habitats of wildlife is one of topics that need in-depth research in road ecology. Crested ibis (Nipponia nippon), a first class nationally protected bird species, is the species of interest in this research. Using the Maximum Entropy Models (MaxEnt) in the Species Distribution Model (SDM) toolbox of ArcGIS, autocorrelation of environmental variables were analyzed and environmental variables with r0.8 were removed. Ten environmental variables were chosen as impact factors for the breeding habitat of crested ibis, including mean temperature of coldest quarter, landscape type, normalized difference vegetation index(NDVI), slope, aspect, distance to waters, distance to paddy field, distance to high-grade roads (expressway, national way, provincial way), and distance to low-grade roads (country road). By analyzing the contribution rate of each environmental variable, the results showed that the mean temperature of coldest quarter, landscape type, distance to paddy field, and distance to high-grade roads were the main factors determining breeding habitat of crested ibis. The suitable distribution of crested ibis' nesting area was under the following scenarios: variable road present (scenario1), high-grade road absent (scenario2), and low-grade road absent (scenario 3). The results showed that the presence of roads affected suitable nesting areas of crested ibis with high-grade roads showing a larger influence than low-grade roads. The presence of high-grade roads and low-grade roads decreased the suitable nesting areas of crested ibis by 66.23 and 35.69 km道路对野生动物适宜繁殖地影响的定量研究是目前道路生态学领域有待深入的内容之一.本文以国家一级保护动物朱鹮为研究对象,利用物种分布模型(SDM)中MaxEnt模型,通过对影响朱鹮繁殖地的环境变量进行自相关分析,剔除自相关系数大于0.8的环境变量,最终选择了10个环境变量为朱鹮繁殖地的影响因子,分别为最冷季度平均气温、景观类型、归一化植被指数、坡度、坡向、距水体距离、距水田距离、距高等级公路(县级及以上道路)距离、距低等级公路(乡镇和林间道路)距离、距居住地距离.通过对环境变量的贡献率进行分析表明: 最冷季度平均气温、景观类型以及距水田距离、距高等级公路距离是影响朱鹮筑巢的主要因子.分别研究了含道路变量(情景Ⅰ)、不含高等级公路(情景Ⅱ)以及不含低等级公路(情景Ⅲ)3种情景下朱鹮繁殖地适宜区分布.结果表明:道路对朱鹮繁殖地干扰影响显著,高等级公路的影响比低等级公路大,高等级公路和低等级公路的存在分别使朱鹮繁殖地适宜区的面积减小了66.23和35.69 km

The warming of the planet in recent decades has caused rapid, widespread permafrost degradation on the Qinghai–Tibet Plateau. These changes may significantly affect soil moisture content and nutrient supply, thereby affecting ecosystem structure and function. This study aimed to describe the dynamic changes in thaw depth, assess the relationship between thaw depth and soil moisture content, and analyze the changes in species composition and water-use efficiency in response to permafrost degradation. We surveyed species composition, thaw depth, ground temperature, soil moisture, nutrient content, and foliar stable carbon isotope compositions to gain insights into the response of alpine grassland ecosystems to permafrost degradation on the Qinghai-Tibet Plateau. Moisture content of the surface layer decreased with increasing thaw depth. The correlation between thaw depth and surface soil moisture content was strongest in June and decreased in July and August. The strongest correlation occurred at a depth of 20 cm to 30 cm. The dominant species shifted from Cyperaceae in alpine meadow to mesoxerophytes in alpine steppe before finally shifting to xerophytes in alpine desert steppe. Thaw depth correlation was significantly negative with organic C content (r = −0.49, P

A model of phosphorus purification in a watershed was established based on the export coefficient and purification index of phosphorus in different types of land cover. The model was employed to simulate the economic value of the ecosystem service with the expected water quality standard and marginal cost of pollutant purification of the upper reaches of Xin' an River of Anhui, China. The results revealed that from 2000 to 2010, some farmland outside the Tunxi, Jixi, Shexian, Yixian and Xiuning was converted to built-up land. The total amount of phosphorus exported to the upper Xin' an River decreased a little, and the main source of phosphorus pollution was farmland and built-up land. More than half of the exported phosphorus was efficiently purified by different types of land cover via flow accumulation. The pattern of purification and export of highly concentrated phosphorus showed the same trend which occurred in the northern part of the watershed including the Yangzhi River, Fengle River and Hengjiang River. Forestland and grassland did not efficiently purify phosphorus in the watershed owing to the irrational distribution of existing land cover. The total service value was 3.80 and 3.31 million Yuan in 2000 and 2010, respectively.

With GIS and RS technology, characteristics of land use change and ecosystem services value of different years in six national nature reserves in Xinjiang, China were analyzed with remote sensing image of the year 2000-2010. Results showed that the area of water body and grassland decreased while the area of forest, farmland, wetland, unused land and construction land increased in 2000-2010. Variation rate of land use change in 2000-2005 was faster, as 2.4-6.3 times as that in 2005-2010. The total ecosystem services value mostly consisted of that of water body, grassland and forest, accounting for 93% approximately. During the study, the values of all kinds of the ecosystem services increased except for grassland and water body, the total ecosystem services value increased firstly and then decreased, and overall emerged as a reducing trend with the rate of 1.2%. In the process of the development of the west regions, it is necessary to pay more attention to the protection of natural resources and ecosystem restoration, so as to achieve sustainable development of resources, environment and social economy in the western regions.

A model was established to simulate an ecosystem service of avoiding reservoir sedimentation and its economic value based on the process of sediment delivery in a watershed. The model included fabricating the watershed of the study reservoir. The sediment retention coefficient of different land cover types were used to simulate the spatial patterns of the annual quantity of the sediment that were prevented from entering the reservoir by the vegetation in each cell followed the flow path in watershed. The economic value of the ecosystem service in this model was determined by the marginal cost of reservoir desilting. This study took the Ertan reservoir as an example. The results showed that most eroded soil was intercepted by different types of ecosystems in the process of sediment delivery in a watershed. The region with a higher quantity of sediment retention was around the reservoir. The absolute quantity of average sediment retention in forestland was lower, so the sediment retention ability of forestland failed to be brought into fullest play in watershed.

Aiming at the fact that the current approaches of evaluating the efficacy of ecosystem provisioning service were lack of spatial information and did not take the accessibility of products into account, this paper established an evaluation model to simulate the spatial distribution of ecosystem provisioning service and its economic value, based on ArcGIS 9. 2 and taking the supply and demand factors of ecosystem products into account. The provision of timber product in Laojunshan in 2000 was analyzed with the model. In 2000, the total physical quantity of the timber' s provisioning service in Laojunshan was 11.12 x 10(4) m3 x a(-1), occupying 3.2% of the total increment of timber stock volume. The total provisioning service value of timber was 6669.27 x 10(4) yuan, among which, coniferous forest contributed most (90.41%). Due to the denser distribution of populations and roads in the eastern area of Laojunshan, some parts of the area being located outside of conservancy district, and forests being in scattered distribution, the spatial distribution pattern of the physical quantity of timber's provisioning service was higher in the eastern than in the western area.

By using software ArcGIS 9.2, an evaluation model was established to simulate the ecosystem service of Ertan Reservoir watershed in mitigating the sand sedimentation in the reservoir. In the meantime, sediment delivery ratio and universal soil loss equation were used to simulate the spatial patterns of the annual sediment yield and sediment retention in the watershed as well as the value during the service life period. In 2000, the total quantity of soil retention in the watershed was 12. 1 x 10(8) t x a(-1). The region with higher soil retention was near the main and branch streams of Yalong River, and that with higher sediment delivery ratio was near the streams and the Ertan Reservoir. The region with higher sediment yield and sediment retention was around the reservoir. The actual sediment yield in the study area was 629.3 x 10(4) t x a(-1), occupying 12.7% of the actual soil erosion volume. Farmland was the most important source of sediment yield, with its sediment yield occupying 62.9% of the total. The contribution of forestland to the mitigation of reservoir sand sedimentation was higher than that of the other lands on a per unit area basis. For the reservoir's designed operating life (100 a), the total value of the watershed in the service of mitigating Ertan Reservoir sand sedimentation was 2.75 billion yuan.

For understanding the regional response to climate change, we explain the characteristics and change of landscape patterns at Huihe National Nature Reserve, Hulun Buir, Inner Mongolia, China. By the visual interpretation method and three-period TM images, we generated landscape classification information with the support of the Arcmap software platform and in combination with ground investigation. The results are as follows: (1) There are four types of landscape in the nature reserve: steppe, wetland, sand and man-made landscapes. (2) The area of the steppe landscape has expanded, and the wetland landscape is gradually diminishing. The area of the sand landscape has remained stable. (3) According to landscape level analysis, there was obvious degradation of landscape in the nature reserve from 1995 to 2006. The change of landscape pattern is influenced mainly by climate change, and human disturbance plays a very important role. Environmental protection could slow the rate of degradation of the ecosystem.

In China the current approaches to evaluating the efficacy of the ecosystem service for avoided-reservoir-sedimentation cannot identify the supplier and beneficiary. In addition, the use of the same whole-country coefficient of sediment delivery for different areas can lead to inaccurate results. Based on the integrated Geographic Information System (GIS) software package, ArcGIS9.2, a new model was established to simulate this ecosystem service and its economic value. The model included fabricating the watershed of the study reservoir. The Sediment Delivery Ratio (SDR) and the Universal Soil Loss Equation (USLE) were used to simulate the spatial patterns of the annual sediment yield and sediment retention in watershed. The economic value in this model of the ecosystem service was determined for a fixed number of years. Taking the Ertan reservoir as an example, the results showed that the actual sediment yield was 629.3×104t•a-1 in the watershed. It occupied 12.7% of the actual soil erosion volume. Farmland was the most important source of sediment yield. Its actual sediment yield occupied 62.9% of the total. The region with a higher quantity of sediment yield and sediment retention was around the reservoir. The contribution ratio of the forest to the avoided-reservoir-sedimentation service value was higher than those of the other contributors on a per unit area basis. For the reservoir’s designed operating life, the total value of this service in the watershed was 27529.2×108Yuan.

Continuous long-term measurements of carbon fluxes have been obtained by improved technology at the ecosystem scale and under natural conditions. Nevertheless, these are still point measurements with limited geographic coverage Quantitative extrapolations and scaling-up of tower station measurements are now urgently needed for carbon cycle research. This paper attempts to solve this problem by combining the technologies of CO2 flux measurements, mathematic modeling, Geographic Information System (GIS) and Remote Sensing (RS). It is well known that the light-response function allows partitioning net ecosystem exchange (NEE) into gross primary production (GPP) and total ecosystem respiration (Re). The GPP and Re can be estimated from continuous CO2 flux measurements using non-linear identification of the non-rectangular hyperbolic model of ecosystem-scale, light response curves. Patterns of the relationships of GPP and Re with the Normalized Difference Vegetation Index (NDVI), and other factors, indicate possibilities to establish multivariate functions, allowing scaling-up of local fluxes to larger areas with GIS technology, temporal NDVI inversed from RS images, and other tools. Our study is based on continuous CO2 flux data, which were measured at the Haibei Alpine Meadow Ecosystem Research Station (Haibei Research Station) on the Qinghai-Tibet Plateau, the Chinese Academy of Science. Using the above methods, we achieved good flux-NDVI relationships at the site and applied these relationships in the scaling-up of site-specific CO2 flux measurements to regional levels. Consequently the annual spatial and temporal variation of CO2 flux was obtained for this plateau and eco-region. Characterizing spatial and temporal dynamics of CO2 flux will facilitate investigations of the carbon source or sink status of grassland ecosystems on the plateau.

Based on the remote sensing images and the meteorological data in 1986 and 2000, and by using the model of extracting vegetation coverage, the spatiotemporal changes of vegetation coverage in the farming-pastoral ecotone of Northern China in 1986-2000 were studied, with the effects of climate and land use change on the changes analyzed. The results showed that in this ecotone, the area with lower vegetation coverage was increasing, while that with higher vegetation coverage was in adverse. The regions with increasing vegetation coverage were mainly in the east of northeast section, the west of north section, and the west of northwest section of the ecotone, while the vegetation coverage in the other sections was obviously degraded. The vegetation coverage were positively correlated with precipitation and aridity index, but negatively correlated with temperature. The change direction and extent of the vegetation coverage varied with land use types.

Based on the RS image of Longitudinal Range-Gorge Region (LRGR) in 2001, the study area was classified into seven first-class landscape types (forestland, grassland, farmland, wetland, water body, urban land, and glacier), and 26 second-class landscape types in consideration of climate belt, vegetation, and topography. By using GIS technology, the services value of different landscape types of LRGR were studied in regards to the study results on services value of Chinese terrestrial ecosystems. The results indicated that the total services value of LRGR was 5 302.35 x 10(8) yuan x a(-1), accounting for 9.47% of the whole country. The service value of soil conservation was the highest, which occupied 18.05% of the total services value, while the service values of gas adjustability and biodiversity protection ranked the second and third. Due to its distribution extent and services intensity per unit area, the forest landscape, which covered 66.11% of the total area, contributed most (85.34%) to the total service value of LRGR, followed by grassland and farmland landscapes.

In 2004 and 2005, a field experiment was conducted in a peach orchard in Pinggu District of Beijing to study the effects of organic manure on the profile distribution of nitrate-N in soil. Four treatments were installed, i.e., applying 6.75 x 10(4) kg x hm(-2) of organic manure both in 2004 and in 2005 (T1), no fertilization in 2004 but applying 13.5 x 10(4) kg x hm(-2) of organic manure in 2005 (T2), no fertilization in 2004 but applying 6.75 x 10(4) kg x hm(-2) of organic manure in 2005 (CK), and no fertilization both in 2004 and in 2005 (CK). In 2006, soil samples at the depth of 0-120 cm were collected from the treatments and analyzed. The results showed that soil nitrate-N had a relatively uniform distribution in the profile in CK, accumulated more at the depth of 0-60 cm and decreased gradually at 60-120 cm in T1 and T3, and increased with increasing depth, with the peak at the depth of 100-120 cm in T2. The soil nitrate-N content below 60 cm in T2 was the highest among all the treatments, indicating that applying excessive amount of organic manure could induce nitrate-N leaching. The profile distribution of soil nitrate-N had significant correlations with the total amount of applied organic manure, the amount of organic manure applied in the nearest year, and the distance of sampling sites from peach tree. A correlation model of organic manure treatments and soil nitrate-N distribution was established.

To reveal the relationships between soil fauna and soil environmental factors in the process of steppe desertification, field survey combined with laboratory analysis was made to study the community structure, population density and biodiversity of soil fauna, and their relationships with the changes of soil organic matter, hydrolysable nitrogen, available phosphorus and moisture contents and soil pH at different stages of desertification of Hulunbeir steppe. The soil faunal specimens collected belonged to 4 phyla, 6 classes and 12 orders. Nematoda was the only dominant group of medium- and small-sized soil fauna, occupying 94.3% of the total, while Coleoptera and Hemiptera were the dominant groups of large-sized soil fauna, with the amount of 79.7%. The group amount, population density, diversity, and evenness of soil fauna had an obvious decreasing trend with the aggravation of steppe desertification. At serious stage of desertification, soil fauna vanished completely. The population density of soil fauna in 0-20 cm soil layer had significant linear correlations with soil nutrients and moisture contents, soil pH, and litter mass, indicating that soil fauna had stronger sensibility to the changes of soil environmental factors in the process of wind erosion desertification of Hulunbeir steppe.