1990—2018年长沙市土地利用变化对生态系统服务价值的影响

评估生态系统服务价值(Ecosystem Service Values,ESV)有利于衡量生态系统服务供给潜力和生态效益的大小,对城市生态规划与土地利用管控起到重要的支撑作用。选择长沙市为研究区域,基于1990、2000、2010和2018年4期土地利用现状遥感监测数据集,利用ArcGIS软件和经本地化校正的当量因子法,分析1990—2018年间的土地利用变化特征,并探讨土地利用变化对ESV的影响。结果表明: ①1990—2018年长沙市土地利用变化轨迹以耕地→林地互相转化以及建设用地对耕地、林地的侵占为主; ②1990—2018年长沙市的ESV共减少53.17×10⁸ 元,降幅3.59%,除水域外各类ESV均呈下降趋势,林地和耕地服务价值减少最明显; ③在各单项服务功能中,水文调节的价值最大,其次是气候调节,两者之和占总价值的54%; ④“退耕还林”“退田还湖”“兴工强市”等政策引起的土地利用变化势必对ESV造成影响,城市快速扩张、土地开发会导致ESV不断下降。综合分析认为,在调整研究区土地利用结构、优化土地配置时应充分重视水域、林地等生态系统服务价值较高的土地利用类型,减缓ESV的下降趋势。     

Ecological effects analysis of land use change in coal mining area based on ecosystem service valuing: a case study in Jiawang

Land use change is one of the uppermost driving forces of regional ecosystem change, and has a huge impact on the environmental balance. Mining areas with intensive resources exploitation and utilization have undergone different kinds of environmental influences, such as water pollution and land use cover change. The extensive coal mining in China has led to significant regional land use change resulting in major ecological damage. The objective of this study was to form a clearer picture of the regional ecological environmental situation for promoting ecological protection and improvement by ecosystem service valuing. The case study area was selected at Jiawang town, which has undergone extensive coal mine exploitation for many decades. The study investigated the relationship between land use change and ecological environment, and described the ecosystem service value variations in Jiawang, based on remote sensing and GIS technology. After modification of regional ecosystem service value coefficients, the method was used to evaluate the conditions in the study area from 1990 to 2005 based on the land use/cover information interpreted from TM/ETM+ images. The characters and changes of ecosystem service values were then analyzed both quantitatively and spatially.     

产业转移背景下区域工业碳排放时空格局演变——以泛长三角为例

产业转移背景下区域能源消费、碳排放格局时空格局变化是近期研究者关注的热点。以处于产业转移期的泛长三角地区为例,以工业能源消费为对象,分析了1990,1995,2000,2005和2010年5个年份碳排放的空间格局和演变规律,探索了产业转移对碳排放格局演变的影响。结果表明,1990年以来工业碳排放稳步增长,高值区集中于长三角核心区;碳排放增长的区域差异较大,热点区域由长三角核心区向外围区转移;碳排放格局发生变化,排放重心呈现先东南向、后西北向移动的态势;工业重心和碳排放重心空间分离,但移动过程类似。研究认为,产业转移所引起的各地区工业产值、产品结构和碳排放强度的变化,与碳排放格局变化具有较大关联性,是影响区域碳排放格局变化的重要因素。     

The impact of land use and land cover changes on soil moisture and hydraulic conductivity along the karst hillslopes of southwest China

The understanding of the temporal and spatial dynamics of soil moisture and hydraulic property is crucial to the study of several hydrological and ecological processes. Karst environments are extremely fragile because of thin soil and small soil water holding capacity. A marked intensification of agricultural land use and deforestation due to increase of population and thus expansion of agricultural areas has made the karst environment even more delicate. In this study, the soil moisture contents (SMC) and hydraulic conductivities (K) along four karst hillslopes were measured in situ by time domain reflectometry and the Guelph Permeameter, respectively, at test plots, each of which has a different vegetative cover, landform, land surface slope, soil property and content of rock fragment. The statistical results from the measurements show that land cover changes strongly affect the distribution of soil moisture and hydraulic properties. Compared with SMC in the bare soil areas, SMC values are 30.5, 20.1 and 10.2% greater in the forest, shrub and grass areas, respectively. Vegetation roots significantly increase permeability of low-layer silt soils. Measured K values were 0.8, 0.6 and 0.01 cm/min for the forest, agriculture and bare soil areas, respectively. When the forest was destroyed by fire or cut to become an agricultural area or bare soils, SMC would be reduced by 13.1 and 32.1%, respectively. If deforestation leads to strong rock desertification, SMC was reduced by 70%. Bedrock fractures significantly reduce the SMC in the overlying layer, but increase K values. SMC values of 30–45% would be reduced to 17–30% for the soil layer embedding rocks with and without fractures, respectively. K values could be increased from 1.0 to 8.5 cm/min. SMC are sensitive to terrain. A slope angle increase of 1° would reduce SMC about 0.82%. These changes resulting from land cover and land use alterations offer useful information to further investigate the response of ecosystem evolution to hydrodynamic processes.     

定量评估我国西北干旱区土地利用变化对植被指数的影响

在全球变化的背景下,定量区分人类活动和气候波动对干旱区植被的影响具有重要意义。采用多种统计学方法,分析了我国西北干旱区1990-2010年土地利用/覆被变化（LUCC）和1982-2010年归一化植被指数（NDVI）的时空变化特征,并定量评估了LUCC对NDVI变化的影响。结果表明：1990-2010年,西北干旱区耕地增加量最多,高达13 476 km²,其次是林地和水域,各地类增加的面积主要来自草地（12 590 km²）和未利用地（6 025 km²）。各土地类型变化速度快慢依次为：耕地 > 建设用地 > 水域 > 林地 > 草地 > 未利用地。2000-2010年,研究区土地利用程度综合指数（0.79）明显高于1990-2000年（0.23）,表明近年来人类活动对土地利用变化的影响程度显著增强。1982-2010年,西北干旱区NDVI呈增加态势,但近年来（2002-2010年）NDVI略有下降。其中,1990-2000年,LUCC对西北干旱区NDVI总变化的贡献率较低,仅为2.9%;而1990-2010,LUCC的贡献率为26.7%,表明气候变化对植被指数变化的贡献率高达73.3%。     

全球岩溶生态系统对比:科学目标和执行计划

由我国提出的新的国际地质对比计划“全球岩溶生态系统对比”（IGCP 448）已于2000年初由IGCP科学委员会批准，在2000－2004的5年中执行。该项目的科学目标是：对比全球不同气候条件下的宏观岩溶生态系统，揭示其形成机理；对比不同地质条件下微观岩溶生态系统，揭示其对物种选择的影响，为岩溶地区石漠化治理，重建良性生态系统探索新思路，从地理，地质角度对比地下岩溶生态系统；研究岩溶生态系统与人类活动的相互作用。5年中除40余个参与国将作好本国岩溶生态系统研究作为全球对比的基础外，还将重点联合考察罗马尼亚，巴西，中国，西班牙，法国，美国，俄罗斯，澳大利亚等国的典型岩溶区，并作深入对比研究，IGCP448的核心科学问题是岩溶生态系统的运行规律，对如何利用我国地域优势和组织该多边国际合作计划的有利条件，进一步做好我国岩溶生态系统研究提出了若干建议。     

An assessment of conservation effects in Shilin Karst of South China Karst

World Heritage is of outstanding universal value and has irreplaceable sources of life and inspiration to humanity. It is important to evaluate the effectiveness of World Heritage site management. As a part of the South China Karst World Natural Heritage, Yunnan Shilin Karst was included in the World Heritage list on 27 June 2007. To quantify the effects of the Yunnan Shilin Karst site conservation, the changes in ecosystem service value of the Yunnan Shilin Karst area and the nearby buffer zone were analyzed by utilizing remote-sensing images, geographic information system and an ecosystem service value model. The results indicate that significant conservation effects of the Yunnan Shilin Karst have been made since 1992, and of the buffer zone since 2004.     

Appraisal of land use/land cover of mangrove forest ecosystem using support vector machine

Human activities in many parts of the world have greatly changed the natural land cover. This study has been conducted on Pichavaram forest, south east coast of India, famous for its unique mangrove bio-diversity. The main objectives of this study were focused on monitoring land cover changes particularly for the mangrove forest in the Pichavaram area using multi-temporal Landsat images captured in the 1991, 2000, and 2009. The land use/land cover (LULC) estimation was done by a unique hybrid classification approach consisting of unsupervised and support vector machine (SVM)-based supervised classification. Once the vegetation and non-vegetation classes were separated, training site-based classification technology i.e., SVM-based supervised classification technique was used. The agricultural area, forest/plantation, degraded mangrove and mangrove forest layers were separated from the vegetation layer. Mud flat, sand/beach, swamp, sea water/sea, aquaculture pond, and fallow land were separated from non-vegetation layer. Water logged areas were delineated from the area initially considered under swamp and sea water-drowned areas. In this study, the object-based post-classification comparison method was employed for detecting changes. In order to evaluate the performance, an accuracy assessment was carried out using the randomly stratified sampling method, assuring distribution in a rational pattern so that a specific number of observations were assigned to each category on the classified image. The Kappa accuracy of SVM classified image was highest (94.53 %) for the 2000 image and about 94.14 and 89.45 % for the 2009 and 1991 images, respectively. The results indicated that the increased anthropogenic activities in Pichavaram have caused an irreversible loss of forest vegetation. These findings can be used both as a strategic planning tool to address the broad-scale mangrove ecosystem conservation projects and also as a tactical guide to help managers in designing effective restoration measures.     

Characterizing land condition variability in Northern China from 1982 to 2011

For the last three decades, Northern China has been considered as one of the most sensitive areas regarding global environmental change. The integration of AVHRR GIMMS and MODIS NDVI data (1982–2011), of which for the overlapping period of 2000–2006 show good consistency, were used for characterizing land condition variability. The trends of standardized annually ΣNDVI, temperature, precipitation and PDSI were obtained using a linear regression model. The results showed that Northern China has a general increase in greenness for the period 1982–2011 (a = 0.05). Also, annually ΣNDVI is significantly correlated with temperature and precipitation data at the regional scale (p < 0.05), implying that temperature and precipitation are the dominant limiting factors for vegetation growth. Since the greening is not uniform, factors other than temperature and precipitation may contribute to greening in some areas, while the grassland and cropland ecosystem are becoming increasingly vulnerable to drought. The results of trend analysis indicate that greenness seems to be evident in most of the study areas.     

Land use history and status of land desertification in the Heihe River basin

An analysis, over historical times, of the influence of natural factors such as climate, geological activity, existing landforms, and the activity of aeolian sands on the desertification of oases and other lands in the Heihe River basin of northwestern China revealed that desertification occurred more or less quickly according to whether the prevailing climate was cold or warm, respectively. In the 1990s, the area of desertified lands in the lower reaches of the Heihe River (Ejin region) was 29.1% greater than in the mid 1980s. However, the rate of desertification in the middle reaches of the Heihe River basin was relatively slower, only 9.4% from 1949 to 1990 (or 0.27% per year). Since 1990, the rate of desertification has been stable. By 2000, the total area of land desertification in the mid to lower reaches of the Heihe River basin was 13,508.4 km², or 11.8% of the region monitored. Of the total land desertification area, the regions of Linze, Gaotai, Sunan, Jiuquan, Jia Yuguan, and Jinta accounted for 1.70, 1.71, 1.43, 0.85, 0.28, and 9.39%, respectively, whereas the Ejin region’s 11,434.64 km² accounted for 84.65%, indicating that land desertification in the lower Heihe River basin was particularly severe. The causes responsible for the occurrence and development of land desertification in the Heihe River basin were analyzed.     

2000-2014年人类活动对贵州省植被净初级生产力的影响

利用MODIS实际净初级生产力数据与CASA模型估算得到的潜在净初级生产力,建立贵州省2000-2014年人类活动相对贡献指数(RCI),并依据各县喀斯特地貌面积和等级比例探究其年际变化及空间分布特征,再通过相关分析辨析选定的人类活动因子对其的影响。结果表明:(1)贵州省RCI均小于-0.5,人类活动促进了植被净初级生产力的增加,以2007年为转折点,影响程度先增强后减弱;(2)贵州省东北部、中部及西部地区的RCI多大于0,人类活动对生态环境有负面干扰作用;东南部及北部边缘地带的RCI多小于-1,人类活动的正面影响较强;(3)贵州省中部、北部大部分地区的RCI缓慢下降,人类活动对植被的正面影响增强;东南部部分区域的RCI由负转正,人类活动负面干扰作用增强;西南边界地区的RCI呈上升趋势却仍为负值,人类干预程度呈减弱趋势;(4)贵州省农业活动在人类活动的负面影响中有重要作用;城镇化与经济发展对生态环境既有正面影响,也有不可避免的负面干扰。     

Changes of land cover in the Yarlung Tsangpo River basin from 1985 to 2005

Land cover is closely related to environmental changes and socioeconomic development. Land-cover change in the Tibetan Plateau (TP) is different from that in the lowlands; however, a detailed land-cover change in areas such as the Yarlung Tsangpo River (YTR) basin in the TP has not been reported. To fill this gap, the current study explores the land-cover change between 1985 and 2005 in the YTR basin. The results show that only 1 % of the land cover in the YTR basin changed during this time period. The most significant land-cover changes included increases in forest and built-up areas as well as decreases in grassland, water and wetland areas. By percentage, the most rapid land-cover change occurred for built-up areas with an annual variation of 2.07 %. There was an obvious vertical distribution pattern for land-cover types in the YTR basin; from low to high, the average altitudes were forest, farmland, built-up, grassland, water and wetland, and bare land. The average altitude and slope for most land-cover types did not vary over the past 20 years. However, the average altitude and slope of built-up significantly decreased, especially in the zone between 3,500 and 4,000 m. The water and wetland area in altitudes above 4,500 m increased; however, they decreased in the zone between 3,500 and 4,000 m. Natural factors cause most land-cover changes, whereas the increasing intensity of human activities cause some changes to built-up and farmland. Additional attention should be paid to the study of the mechanism of land-cover change in the TP.     

Spatial pattern of Karst rock desertification in the Middle of Guizhou Province,Southwestern China

Karst rocky desertification is a typical type of land degradation in the Southwestern China. It has great ecological and economical implications for the local people. Landsat images from the middle of Guizhou Province collected in 1974, 1993 and 2001 were used for change detection of the pattern of Karst rocky desertification. The results show the following findings: (1) Desertification area expanded drastically in 27 years, at an increasing rate about 116.2 km²/year. (2) High areas (900–1,500 m) are the most affected. (3) Areas with the slope <5° or >25° are also easily tend to be Karst rocky deserted. (4) The process of Karst rocky desertification is nearly irreversible. Few areas of Karst rocky desertification could be meliorated to non-desertification land. (5) Most of the degraded lands are located in the south and the central of the study region, and the meliorated land areas are sparsely located in the east and the west part of the region. All these findings would provide bases for the decision-making of the local government to improve the Karst rocky desertification     

Urban expanding pattern and soil organic, inorganic carbon distribution in Shanghai, China

Soil carbon stock changes induced by land-use change play an essential role in the global greenhouse effect and carbon circulation. This paper studies the urban expanding patterns and spatial characteristics of soil organic carbon (SOC) and soil inorganic carbon (SIC) distribution and evolution during the urbanization process of Shanghai, China, based on the data of the regional geochemical survey. Urbanization process in Shanghai, China, has been quickening greatly since the 1980s. The urban area expanded from 193.08 km² in 1980 to 1,570.52 km² in 2005, or up from 3.05 to 24.77% in the past 25 years, and the urban expansion circled the central city region according to the RS images acquired in the periods of 1980, 2000 and 2005. The urban topsoil is slightly enriched with SOC and SIC, which shows obvious spatial variability. By comparison of SOC and SIC distribution in the central urban area, urbanized area during 1980–2000, 2000–2005 and the suburban area, the SOC obviously accumulates in the central urban area, while SOC density in the urbanized area decreases; similarly, the SIC obviously accumulates in central urban area; furthermore, the SIC density increases with urban land use duration extending and urban ecosystem evolving. This paper provides the characteristics of SOC and SIC distribution and evolution during the course of urbanization, which may be useful for assessing the impact of land use and urban development on SOC and SIC pools in urban ecosystem.     

The changes of vegetation cover in Ejina Oasis based on water resources redistribution in Heihe River

The Ejina Oasis (EO), located in arid northwest China, is a typical arid area in the world. The ecosystem in the oasis has become worse since the 1990s. However, it began to improve after the Chinese government took the mandatory measure to redistribute the water in Heihe in 2000. To understand this change, the remote sensing images in 1990, 2000 and 2006 were selected, and exertion related Land Use/Cover Change (LUCC) model was employed. Results showed that: (1) non-vegetation cover was the main body of the vegetation cover in oasis, showing a trend of increase at the beginning and diminution later, while low, medium and high vegetation cover was the other way around; (2) the area of low, medium and high vegetation cover in 2006 was less than that in 1990; the status and trend index P _t of oasis vegetation cover was 0.62 in 1990–2000, which means that the oasis ecosystem of Ejina was getting worse and was under an unbalanced status; P _t was 0.27 in 2000–2006 indicating that the oasis ecosystem was restored obviously and the whole system tended to be balanced; (3) all of these changes should be attributed to the water resources redistribution in Heihe River, which played a leading role, as well as the measures and relevant policies taken by the local government, which promoted the rapid recovery of the medium and high vegetation.     

Drought as an agri-environmental determinant of irrigation land: the case of Bardenas (Spain)

Irrigated agriculture is causing certain deterioration of the quality of rivers and aquifers. The objective of this study is to analyse the agri-environmental repercussions caused by climatic changes in a typical irrigated land in the Ebro valley (Spain). The irrigation efficiency and agri-environmental impact in a basin of irrigated land (95 ha) were compared for two hydrological years with different pluviometry [October 2000/September 2001 (526 mm/year) vs. October 2004/September 2005 (211 mm/year)]. For this end, water balances were carried out in every plot and the quantity and quality (salinity and nitrates) of the water circulating through the drainage of the basin were gauged. The results indicate that in 2004/2005 farmers adjusted the irrigation doses better on each irrigation occasion, thus diminishing the fraction of drainage of the same (50% vs. 31%) and increasing the consumptive water use efficiency (56% vs. 79%). Nevertheless, the drought of 2004/2005 determined inappropriate irrigation management as the crops suffered a greater hydric deficit (3% vs. 23%). In 2004/2005, drainage waters presented higher electric conductivity (0.92 dS/m vs. 0.94 dS/m) and smaller nitrate concentration (96 mg/l vs. 74 mg/l). Last year, 55, 54 and 65% less of water, salts and N–NO₃⁻, respectively, were exported in the drainage. The lesser environmental impact in the year 2004/2005 was influenced by more appropriate use of water and agrichemical resources. Nevertheless, it is necessary to continue optimizing agricultural practices, mainly irrigation and fertilization, in order to minimize nitrate pollution and to confront years of drought.     

天山南坡科契卡尔巴西冰川物质平衡初步研究

基于2003—2005年考察期间观测的气温与降水资料,运用度日物质平衡模型模拟了天山南坡科契卡尔巴西冰川近期的物质平衡变化状况.结果表明:度日物质平衡模型模拟的冰川物质平衡值与实测值的变化趋势基本一致,模型模拟结果较为理想;2003/2004年度和2004/2005年度两个物质平衡年的平均物质平衡值分别为-494和-384 mm,平衡线高度(ELA)比20世纪70年升高了300 m左右.由此可见,在由暖干向暖湿转型的气候背景下,尽管降水增加显著,但强烈的升温导致科契卡尔巴西冰川处于强烈的物质亏损状态.     

Driving forces of aeolian desertification in the source region of the Yellow River: 1975–2005

The source region of the Yellow River, located in the northeastern portion of the Qinghai–Tibet Plateau, plays a critical role in water conservation, biodiversity protection, and wetland conservation. Aeolian desertification of this area is an important concern. Remote sensing and GIS technology were employed to assess the trends in aeolian desertification from 1975 to 2005. The monitoring results showed that, aeolian desert land increased from 15,112 to 17,214 km² during 1975–2005. In addition, it was found that the area of aeolian desertification increased rapidly from 1975 to 1990, was stable from 1990 to 2000, and slightly decreased from 2000 to 2005. Increasing temperature, overgrazing, and drainage of wetlands have been key driving factors of aeolian desertification. Thus, to control the expansion of aeolian desert lands in the source region of the Yellow River and to rehabilitate existing desert areas, the priority should be given to altering human behavior in these areas.     

典型岩溶湖泊湿地流域景观格局动态变化及趋势预测

岩溶湖泊湿地流域作为景观格局变化的热点研究区域,探讨景观格局动态变化及预测趋势,为岩溶流域生态安全研究提供科学依据。应用遥感与地理信息系统技术,结合普者黑岩溶湖泊湿地流域实际情况,分别对该地区1990、1995、2000、2005、2010、2015 年6 期遥感影像进行分类、解译,系统地获取地区景观格局状况,分析动态变化特征,并运用CA-Markov 模型对未来湿地景观格局进行模拟预测。结果表明:1990?2015年普者黑岩溶湿地流域景观格局随时间变化显著,景观破碎化程度总体呈现增加趋势,斑块数（NP）从861增加到889,景观类型的优势斑块面积在逐渐增加,而多样性指数从1.064下降到0.966;2020?2030年普者黑岩溶湿地流域建筑用地、农地和湿地景观类型面积在增加,农地和林地在减少,其中,较为突出的是建筑用地占有率由2.79%上升到2.97%,农地占有率60.12%增加到60.74%,湿地占有率6.67%上升7.02%,而林地占有率由26.70%下降到26.40%。景观格局进行预测可以发现湿地面积、建筑用地面积和农地变化幅度最大,本文相关研究和预测结果可为普者黑流域生态保护提供一定的建议和参考。      

Developing an integrated urban ecological efficiency framework for spatial ecological planning: A case on a tropical mega metropolitan area of the global south

Rapid urbanization has emerged as one of the most critical challenges to ecological sustainability in urban areas. In developing countries, the degradation of the ecosystem is more prominent due to the lack of urban planning. Thus, it has become urgent for researchers to identify the ecological efficiency (EE) changes imposed by urban expansion and promote sustainable land use planning. This study aims to develop a comprehensive urban ecological efficiency (UEE) framework in the Kolkata Metropolitan Area (KMA), India, from 2000 to 2020. Principal component analysis (PCA) was used to develop a remote sensing-based UEE index (UEEI) based on five effective ecological parameters (Greenness, Dryness, Heat, Wetness and vegetation health. A single sensitivity parameter was also calculated to determine the role of a single parameter based on which management strategies can be carried out. The findings showed that (i) there were substantial deteriorations of UEE in the last 20 years. In 2000 the areas with good EE were about 65.5% which declined to 53.72% in 2010 and 20.87% in 2020. The areas with good UEE decreased 68% and 61% from 2000 to 2020 and 2010 to 2020, respectively; (ii) the areas with good UEE were 52% in 2000, while 38% in 2010. Most urban centres (Bhadreshwar, Champdani, Srirampur, Bally, Howrah, Kamarhati, Baranagar, Dum Dum, South Dum Dum, Rajarhat, Bidhannagar) located around the Kolkata megacity are characterized by poor and very poor EE (ranges of 0.60–1.00). Thus, spatiotemporal pattern of UEE could assist to clarify the administrative responsibilities as well as obligations. In addition to this, the UEE framework can help for scientific guidance of urban ecosystem protection and restoration through comprehensive spatial landscape planning.