Areas Benefiting from Water Conservation in Key Ecological Function Areas in China

Ecosystem services are transferred from the service-providing area to the service-benefiting area to satisfy human needs through some substance, energy or information. Most studies focus on the provision of ecosystem services and few focus on the demands on ecosystem services and their spatial distribution. Here, on the basis of the flow of water conservation services from the providing area to the benefiting area, the benefits produced by water conservation service are investigated and the benefiting areas are identified. The results indicate that in 2010 the water conservation service of key ecological function areas provided irrigation water for 1.67×105 km² of paddy fields and 1.01×10⁵ km² irrigated fields, domestic water to urban residents and industrial water to factories, mines and enterprises of 2.64×10⁴ km² urban construction land and domestic water to rural residents across 3.73×10⁴ km² of rural settlements and formed 6.64×10⁴ km² of inland water which can be used for freshwater aquaculture, downstream regions comprise 1.31×10⁴ km of navigable river, which can be used for inland shipping. The benefit areas of the key function areas located in the upper and middle reaches of the Yangtze River are greater and more influential benefit areas. To protect these key function areas, more attention should be paid to the maintenance and improvement of water conservation. Some benefit areas have access to the benefits produced by water conservation of nine key ecological function areas and cover 17% of the overall benefit area and the length of their channels benefited accounts for 7%. Multiple key ecological function areas should be taken into account equally in the formulation of ecological compensation policies. These research findings can serve as a scientific basis for the compensated use of and ecological compensation for ecosystem services provided by key ecological function areas.     

Evaluation of Inner Mongolia Wind Erosion Prevention Service based on Land Use and the RWEQ Model

Inner Mongolia is the important ecological barrier zone in northern China, which plays an important role in the prevention and control of wind in the regional ecosystem. Based on the Revised Wind Erosion Equation (RWEQ) model and the cost-recovery method, this study simulated the wind erosion prevention service (WEPS) in Inner Mongolia in 2010 and 2015, investigated the spatial pattern of material and monetary value of WEPS, and analyzed the differences among various cities and various ecosystems. The results indicated that the total WEPS of Inner Mongolia was estimated to be 73.87×10⁸ t in 2015, which was 4.61×10⁸ t less than in 2010, while the monetary value of WEPS was calculated to be 738.66×10⁸ yuan in 2015, which was 46.16×10⁸ yuan less than in 2010. Among all the leagues and cities, Xilin Gol League supported the highest WEPS, reaching 18.65×10⁸ t in 2015, while Wuhai provided the lowest. The WEPS of Hulunbeier increased the most, by 4.37×10⁸ t from 2010 to 2015. The WEPS in the grassland ecosystem was the highest among the different ecosystems, accounting for more than 55% of the total WEPS in Inner Mongolia, but it was reduced by 1.05×10⁸ t during the same period. The WEPS in the forest ecosystem increased the most, reaching 0.19×10⁸ t. This study found that the implementation of projects such as returning farmland to forests and grasses and sand control effectively increased the WEPS by increasing the forest area. However, unsuitable land use increased the desertification of ecosystems which resulted in a reduction of WEPS in Inner Mongolia.     

Ecosystem Service Value Assessment for National Key Eco-function Zones for Water and Soil Conservation

National key eco-function zones for water and soil conservation are exceptionally fragile areas in terms of their eco-environments and are also severely affected by water and soil loss. They have been a focus of attention from all sectors of society. This research assesses important ecosystem service functions and their values using such indexes as NPP, soil conservation quantity and water conservation quantity. The result indicates that the ecosystem services of China’s eco-function zones for water and soil conservation are worth 3268.90×10⁸ CNY in total, of which organic matter production accounts for 530.96×10⁸ CNY, nutrient substance circulation and storage 301.91×10⁸ CNY, carbon fixation and oxygen release 1616.16×10⁸ CNY, soil conservation 442.70×10⁸ CNY and water source conservation 816.20×10⁸ CNY. Of the four functional zones, the Guangxi-Guizhou-Yunnan Area registers the highest value of 1551.30×10⁸ CNY, and the Three Gorges Reservoir Area the lowest value of 448.15×10⁸ CNY. In terms of ecosystem service value per unit of area, the Guangxi-Guizhou-Yunnan Area takes the first place, followed by Three Gorges Reservoir Area and the Dabie Mountain Area, which are roughly equivalent, and finally the Loess Plateau Area is at the bottom.     

1992-2015年中亚五国土地覆盖与蒸散发变化

1991年苏联解体,中亚五国独立使得土地覆盖与蒸散发格局发生深刻变化。以中亚五国为研究区,采用欧空局气候变化项目（CCI）土地覆盖和全球陆地数据同化系统（GLDAS）蒸散发数据,分析1992-2015年土地覆盖与蒸散发时空变化特征,进一步研究耕地蒸散耗水特征。结果表明：① 中亚五国土地覆盖变化具有阶段性特征,耕地扩张引起土地覆盖格局变化。1992-2003年耕地快速增加（1.1万km ²/a）,林地和草地大幅减少。2003-2015年耕地增速趋缓（0.3万km ²/a）,林地和草地有一定恢复,裸地和水体持续减少,城镇用地持续增长。耕地共增加12.3万km ²,林地和草地分别减少4.0万km ²和2.3万km ²,且集中于哈萨克斯坦中北部。裸地减少3.5万km ²,集中于哈萨克斯坦西南部,水体减少3.1万km ²,集中在咸海湖泊。乌兹别克斯坦耕地减少、裸地增加,吉尔吉斯斯坦、塔吉克斯坦和土库曼斯坦土地覆盖变化幅度较小;② 中亚五国蒸散发变化与土地覆盖格局基本一致。蒸散发总体呈增加态势（6 mm/a）,1992-2003年快速增加（11.3 mm/a）,2003-2015年缓慢上升（2.4 mm/a）。中亚五国年蒸散发达到276.8 mm,东南部的吉尔吉斯斯坦（347.3 mm）和塔吉克斯坦（302.9 mm）最高,中北部的哈萨克斯坦（297.9 mm）次之,西南部的乌兹别克斯坦（211.0 mm）和土库曼斯坦（150.0 mm）最低;③ 中亚五国蒸散耗水结构受耕地面积大小的影响。中亚五国耕地蒸散耗水的贡献由24.7%增至27.9%,土库曼斯坦耕地蒸散耗水仅占本国的11%,其他国家均超过25%。草地、林地和裸地的蒸散耗水贡献降低,但哈萨克斯坦、吉尔吉斯斯坦和塔吉克斯坦仍以草地和林地蒸散耗水为主（≥ 50%）,土库曼斯坦（61.3%）和乌兹别克斯坦（46.4%）的裸地蒸散耗水占绝对优势。本文明确了中亚五国土地覆盖连续动态变化过程,细化各国土地覆盖与蒸散发特征及差异,增强对土地覆盖与蒸散发现状的认识,可为水土资源管理和生态环境保护提供数据参考。     

Spatial and Temporal Patterns of Supply and Demand Balance of Water Supply Services in the Dongjiang Lake Basin and Its Beneficiary Areas

Water-related ecosystem services is a hot topic in ecological research. Water supply services are crucial to regional water cycles and water quantity balance. The Dongjiang Lake basin is a national priority river basin in China where ecological compensation pilot programs concerning water resources and water supply services are top priorities for ecosystem service protection. We analyzed spatial and temporal patterns associated with generation and use of water supply services in the Dongjiang Lake basin using the InVEST model, socio-economic data and water resource data. We found that between 1995 and 2010, water yield in the Dongjiang Lake basin and its beneficiary areas increased before declining, varying 9350-12 400 m³ ha^-1 y^-1; average water yield peaked in 2000. The spatial distribution patterns of water yield during these years are similar, progressively decreasing from upstream to downstream with a remarkable reduction in surrounding areas of city clusters. Average water consumption of the basin and its beneficiary areas ranged from 2900-4450 m³ ha^-1 y^-1 between 1995 and 2010; the spatial distribution patterns of water consumption during these years are similar, dropping gradually from urban construction land to its surroundings with a stronger gradient between urban and rural areas. More water was consumed on both banks and surroundings of the lake. From 1995 to 2010, water supply fell short of demand for urban construction land and its proximity as well as areas along the lake. Water supply services were able to satisfy needs in other regions. The Changsha-Zhuzhou-Xiangtan city cluster suffers from the most strained water supply.     

陕北地区土地生态系统固碳释氧价值量动态测评

基于1980-2010年的遥感数据和气象台站实测数据,利用光能利用模型对陕北地区植被净第一生产力进行了测评,从而计算得到植被固碳释氧价值量,并分析了其变化特征。不同土地利用类型固碳释氧物质总量排序为：草地>林地>耕地>未利用地>建设用地。空间分布上,陕北地区南部和北部府谷县和神木县固碳释氧价值总量变化的波动性较强,陕北西北部碳释氧价值总量的年际变化较为平缓。近30年来,陕北地区固碳释氧价值总量总体上呈持续增加趋势,固碳释氧价值总量增加的区域主要分布在榆林中北部地区,且大部分呈可持续增加趋势;减小区主要分布在陕北西南部的甘泉县、富县、黄陵县、志丹县的南部以及延安市南部的富县与宜川县的交界处,且呈强烈的持续减小趋势。生态固碳释氧价值量与月降水量整体上呈正相关,与月均温呈负相关。固碳释氧价值量的变化对降水量的变化响应较敏感,气温需要通过与其他气候系统进行耦合,从而协同对固碳释氧价值量产生影响。陕北地区生态系统固碳释氧价值总量受降水量的影响较强,两者在空间上呈现出正相关,且由南向北、由东南向西北呈减小的趋势;价值总量与气温的相关系数由南向北逐渐增加,中南部呈负相关,北部呈正相关。     

Land Cover Status in the Koshi River Basin,Central Himalayas

The Koshi River Basin is in the middle of the Himalayas, a tributary of the Ganges River and a very important cross-border watershed. Across the basin there are large changes in altitude, habitat complexity, ecosystem integrity, land cover diversity and regional difference and this area is sensitive to global climate change. Based on Landsat TM images, vegetation mapping, field investigations and 3S technology, we compiled high-precision land cover data for the Koshi River Basin and analyzed current land cover characteristics. We found that from source to downstream, land cover in the Koshi River Basin in 2010 was composed of water body (glacier), bare land, sparse vegetation, grassland, wetland, shrubland, forest, cropland, water body (river or lake) and built-up areas. Among them, grassland, forest, bare land and cropland are the main types, accounting for 25.83%, 21.19%, 19.31% and 15.09% of the basin’s area respectively. The composition and structure of the Koshi River Basin land cover types are different between southern and northern slopes. The north slope is dominated by grassland, bare land and glacier; forest, bare land and glacier are mainly found on northern slopes. Northern slopes contain nearly seven times more grassland than southern slopes; while 97.13% of forest is located on southern slopes. Grassland area on northern slope is 6.67 times than on southern slope. The vertical distribution of major land cover types has obvious zonal characteristics. Land cover types from low to high altitudes are cropland, forest, Shrubland and mixed cropland, grassland, sparse vegetation, bare land and water bodies. These results provide a scientific basis for the study of land use and cover change in a critical region and will inform ecosystem protection, sustainability and management in this and other alpine transboundary basins.     

生态政策驱动下的内蒙古自治区杭锦旗土地利用及生态系统服务价值变化

基于1989、2001、2013年的遥感影像解译数据,采用生态系统服务价值评估方法,对生态政策实施前(1989—2001年)及实施后(2001—2013年)的内蒙古自治区杭锦旗土地利用及生态系统服务价值变化进行了对比分析。结果表明:生态政策实施后杭锦旗林地面积变化量为12.84×10⁴ hm²,高于实施前的0.24×10⁴ hm²;沙地面积变化量为-7.20×10⁴ hm²,高于实施前的-0.27×10⁴ hm²。生态政策实施后土壤形成与保护功能的生态系统服务价值增加4.22亿元,高于实施前的0.20亿元;水源涵养功能的生态系统服务价值增加3.43亿元,高于实施前的2.19亿元;总生态系统服务价值增加23.82亿元,高于实施前的5.61亿元。通过实施生态政策,杭锦旗土地利用结构得以优化,生态系统服务价值得以提高,水土保持能力得以增强。但水域退化、耕地转换合理度较低等问题仍有待解决,论文对此也提出了相应的对策建议。     

生态系统服务权衡与协同视角下的重点生态功能区保护特征

重点生态功能区提供着源源不断的生态系统服务,在保障国家生态安全和社会可持续发展方面,有着不可或缺的基础作用。但是,以生态系统服务权衡与协同关系为视角,进而探讨分析重点生态功能区保护特征的研究案例相对较少。本文以秦巴重点生态功能区为评估分析区域,选择自然地理条件相似度极高的秦巴山区为参照单元,以生态系统供给服务与调节服务为核心内容,在定量分析2000—2019年期间的生态空间变化特征基础上,分析评估生态系统服务权衡与协同关系。结果表明：秦巴山区生态状况逐渐变好,重点生态功能区划定之后,生态系统趋于稳定;重点生态功能区服务能力呈逐渐增强的趋势,平均净初级生产力、土壤保持总量和水源涵养总量比重点生态功能区外分别高出了25.95 gC/m²、5.81亿t和24.95亿m³;土壤保持服务和生态系统供给服务的协同关系与生态状况改善呈正相关;由于受到降水的影响,2010年之后的水源涵养服务与生态系统供给服务的协同关系变差。总体来看,秦巴重点生态功能区的划定带动了区域生态空间“量的增长”和生态系统服务“质的提升”,但生态系统服务之间关系的“协调性”仍然不足,甚至从“协同”转为“权衡”关系,这要求未来国家需要制定更有针对性的生态系统保护管理决策,提高生态系统总体效益,支撑区域生态系统服务的可持续供给。     

托木尔峰国家级自然保护区土地利用/覆被生态服务价值变化分析

参照中国陆地生态系统服务价值当量,结合研究区不同土地利用∕覆被类型的生物生产量,研究各土地利用/覆被类型的生态服务价值变化。结果表明：① 1989-2014年,冰川面积增长27.63%,草地增长35.69%,水体减少55.43%,荒地减少13.81%,林地减少9.87%;1989-2002年的区域综合动态度为0.72%,2002-2014年的为0.62%。② 保护区的生态服务价值为52.31×10⁸元/a,突出了保护区重要的生态地位。在保护区11项生态服务功能中,水文调节和水资源供给生态服务功能价值最高,食物和原料生产生态服务功能价值较低。③ 1989-2014年生态服务总价值量降低31.49%,其中冰川和草地的总价值量持续增长27.63%和35.70%,水体和荒地的持续减少55.43%和13.81%,林地的先减22.13%,后增15.75%。在价值构成比例上,1989年水体占主要地位,2014年冰川占主要地位。     

The Population Carrying Capacity of Waters Ecosystem in China

The study of waters ecosystem and their population carrying capacity demonstrates the role of these ecosystems in economic and social development and provides a theoretical basis for the management and allocation of aquatic ecosystems. In this study, the concept of waters ecosystem population carrying capacity was defined and developmental trends in the population carrying capacity of waters ecosystem in China were evaluated. Results show that waters ecosystem population carrying capacity in China increased from 0.176×10⁹ person year^-1 in 2000 to 0.255 ×10⁹ person year^-1 in 2010; the population carrying capacity of the standard sea remained at 0.2-0.3 person ha^-1; and the standard inland waters population carrying capacity increased from 1.8 to 3.2 person ha^-1. This analysis indicates notable regional difference in waters population carrying capacity. In southeastern coastal China and Yangtze River drainage areas where inland waters are widely distributed and aquaculture is developed, the population carrying capacity is higher; however, in northwest China where water resource are deficient and the distribution is relatively small, the waters population carrying capacity is low. The waters ecosystem population carrying capacity of China in 2030 was predicted and results indicate strong potential for increasing waters population carrying capacity.     

2010-2015年中国土地利用变化的时空格局与新特征

土地利用/覆被变化是人类活动对地球表层及全球变化影响研究的重要内容。本文基于Landsat 8 OLI、GF-2等遥感图像和人机交互解译方法,获取的土地利用数据实现了中国2010-2015年土地利用变化遥感动态监测。应用土地利用动态度、年变化率等指标,从全国和分区角度揭示了2010-2015年中国土地利用变化的时空特征。结果表明：2010-2015年中国建设用地面积共增加24.6×10³ km²,耕地面积共减少4.9×10³ km²,林草用地面积共减少16.4×10³ km²。2010-2015年与2000-2010年相比,中国土地利用变化的区域空间格局基本一致,但分区变化呈现新的特征。东部建设用地持续扩张和耕地面积减少,变化速率有所下降;中部建设用地扩张和耕地面积减少速度增加;西部建设用地扩张明显加速,耕地面积增速进一步加快,林草面积减少速率增加;东北地区建设用地扩展持续缓慢,耕地面积稳中有升,水旱田转换突出,林草面积略有下降。从“十二五”期间国家实施的主体功能区布局来看,东部地区的土地利用变化特征与优化和重点开发区的国土空间格局管控要求基本吻合;中部和西部地区则面临对重点生态功能区和农产品主产区相关土地利用类型实现有效保护的严峻挑战,必须进一步加大对国土空间开发格局的有效管控。     

基于遥感与GIS的新疆近18 a来LUCC的生态环境效应分析

 基于遥感与GIS技术,以20世纪80年代末、90年代末、2005年、2008年遥感影像为数据源,获取4期新疆土地利用/覆盖信息,采用生态系统服务价值、生态环境质量指数和土地利用/覆盖转变类型生态贡献率,对研究时段内新疆土地利用/覆盖变化的生态环境效应进行了综合分析与评价。结果表明,1990—2008年间,新疆土地利用/覆盖变化显著,生态系统服务价值整体变化较小,总价值先增后减,水域和草地面积的减少是总价值减少的主要原因,耕地和林地面积的增加补偿了总价值的部分损失;生态环境质量指数从1990年的0.157持续下降到2005年的0.153,2008年上升为0.158,说明新疆生态环境存在恶化和改善两种相反趋势,导致生态环境恶化的主要原因是草地向耕地的转变,未利用地向草地的转变则促进生态环境质量的改善。     

Trade-off and Synergy Relationships of Ecosystem Services and Driving Force Analysis based on Land Cover Change in Altay Prefecture

Altay Prefecture plays a vital role as an ecological barrier in Northwest China. Studying the ecosystem service value is of great significance for promoting regional green high-quality development and maintaining ecological security. Based on Global ESA land cover data from 2000 to 2015, the trade-off and synergy relationships and driving force factors between ecosystem services in Altay Prefecture were analyzed in this study. The analysis produced four main results. (1) The ecosystem service value in Altay Prefecture continued to increase from 113.521Ⅹ10⁹ yuan in 2000 to 115.777Ⅹ10⁹ yuan in 2015, for an increase of about 1.98%. (2) The distribution of ecosystem service value had obvious spatial agglomeration characteristics, with hot spot areas mainly concentrated in the "two rivers and one lake" and the mountainous areas in the northwest, while the cold spot areas were mainly the forest and grass-covered areas in the northern mountainous areas and within Jimunai County. (3) The trade-off and synergy relationship among ecosystem services was mainly synergistic, with a total of 77.78% of ecosystem service relative relationships showing a significant positive correlation at the 0.01 level. (4) Economic factors and industrial structure are important factors affecting ecosystem service value in Altay Prefecture. Ecosystem service value is positively correlated with per capita GDP and the output value of the tertiary industry, but negatively correlated with the output value of the secondary industry.     

祁连山黑河径流变化特征及影响因素研究

基于黑河流域径流、气象和土地利用类型等资料,采用弹性系数等方法研究了黑河径流变化特征及影响因素。结果表明：（1） 1990年后黑河流域径流量增加趋势明显加速,并且在黑河干流表现最为明显,1957—1990年莺落峡站径流量增加速率为0.75×10⁸ m³·(10a)^-1,而1991—2020年其增加速率为2.60×10⁸ m³·(10a)^-1,后者是前者的3.47倍,并且黑河全流域1990年后径流量增加主要发生在夏季和秋季,较1990年前分别增加了7.07%和26.58%。（2） 径流对气候变化的响应在夏季最为敏感,并且降水是导致径流增多的主要气候因素,夏季降水量增多1.000%,同期径流量平均增多0.741%（P<0.01）。（3） 2020年较1980年黑河流域耕地和建设用地面积相对增幅分别为24.20%和71.43%;草地和未利用土地面积相对降幅分别为1.30%和5.28%。径流量与林地面积、建设用地面积呈正相关,而径流量与草地面积呈负相关。研究结果可以为黑河流域水资源的科学管理、优化配置和后续生态工程的实施提供参考。     

Responses of Ecosystems to Ecological Compensation in a Key Ecological Function Area of the Loess Plateau

Evaluation of the ecological effects of eco-compensation policies helps analyze policy rationality and feasibility and provides scientific and practical bases for perfecting eco-compensation systems. Taking the key ecological function area of the Loess Plateau, China as a case study, we have evaluated ecosystem responses to the Grain-for-Green Project that commenced in 1999. Six indicators were selected to assess changes in ecosystem structure, quality and function. The results showed that implementation of the Grain-for-Green Project has reduced sloping cropland by 1571 km² and increased ecological land by 1337 km². The increase in ecological land alters ecosystem structures across the study area and the decline in sloping cropland reduces farming activity interference; both of these are conducive to the restoration of natural vegetation. From 2000 to 2010, the vegetation cover of grassland, desert and forest ecosystems increased 10.89%, 8.34% and 4.24% respectively and average NPP rose 51%, with an average annual growth rate of around 5%. This indicates that eco-compensation has promoted the improvement of ecosystem quality. Total biomass of ecosystems increased two times on average from 2000 to 2010, meaning that the carbon sequestration capacity of ecosystems also increased. The reduction in the area of water loss and soil erosion and the increase in retained runoff by forests indicate an improvement in ecosystem function and services on the Loess Plateau.     

Values of the Farmland Ecosystem Services of Qingdao City,China, and their Changes

The values of farmland ecosystem services are composed of several components: provisioning service value, regulating service value, supporting service value and cultural service value, so it is important to make a full assessment of the values of farmland ecosystem services for agriculture and farmland protection. Here, we assessed the values of farmland ecosystem services in Qingdao City in 1997, 2002, 2007, 2012 and 2017 by using various methods (market value method, carbon tax method, afforestation cost method, substitute cost method, equivalent factor method, etc.) based on establishing an assessment index system for the farmland ecosystem services value. The results show that the total yearly value of farmland ecosystem services increased from 499.74×10 ⁸ Yuan to 681.74×10 ⁸Yuan in the period of 1997-2017, and the yearly value of farmland ecosystem services per hectare increased from 6.57×10 ⁴ Yuan to 9.73×10 ⁴Yuan. The product provisioning service, carbon fixation service and oxygen release service, as well as the soil conservation service, are the main farmland ecosystem services, and the proportions of these four ecosystem service values to the total value of farmland ecosystem services in Qingdao City were large and kept increasing. Some countermeasures are put forward to adequately use the indirect service value of the farmland ecosystem and provide improved well-being for humans, such as protecting and wisely using farmland, developing agriculture that is rooted in local conditions, promoting agricultural production efficiency, speeding up construction of modern agriculture gardens, deepening the supply-side structural reform of agriculture, developing agricultural eco-tourism, etc.     

2000-2015年城市和工矿用地扩张对净初级生产力的影响

中国近15 a来快速的城市化和工业化对陆地净初级生产力（Net Primary Productivity,NPP）的影响是关系到碳循环和全球变化效应的重要问题。首先,本文基于VPM（Vegetation Photosynthesis Model）模型得到NPP数据,基于中国土地利用数据集（National Land Use Datasets of China（NLUD-China））获取2000-2015年城市和工矿用地数据,然后通过邻域替代法模拟2000-2015年间因中国城市和工矿用地扩张损失的陆地NPP。结果表明：2015年城市和工矿用地占中国国土总面积的1.2%,在2000-2015年间面积增加了70×10³ km²。城市和工矿用地扩张导致陆地NPP损失1.24 TgC·a^-1到3.14 TgC·a^-1,在2005-2010年损失NPP最多（3.14 TgC·a^-1）。耕地被建设用地占用是造成中国陆地NPP损失的重要原因,在2010-2015年共有13×10³ km²的耕地被城市和工矿用地占用,因此损失的NPP达1.51 TgC·a^-1,占中国城市和工矿用地扩张损失NPP总量的82%。从时空分布特征来看,21世纪初剧烈的城市扩张造成沿海和中部地区NPP损失严重（2000-2005年沿海地区主要因城市扩张损失NPP高达0.82 TgC·a^-1）,而2010-2015年主要因工矿用地扩张使西部地区NPP损失升高（在2010-2015年因工矿用地扩张损失NPP 0.46 TgC·a^-1,占中国NPP损失总量的30.81%）,NPP损失量呈现出从东高西低逐渐过渡到东西平衡的时空格局。从影响上分析,城市和工矿用地不透水地表比例（0.59±0.19）高于自然植被的不透水地表比例（0.29±0.14）,并且城市内部透水地表的平均标准化NPP（0.9）低于自然植被的平均标准化NPP（1.1）,是造成城市和工矿用地损失NPP的主要原因。     

基于物质量评估的贵州南部地区生态系统服务及其县域差异比较

以贵州南部地区为例,对涵养水源、固碳释氧、净化大气环境、保育土壤和生物多样性保护5个功能类别共14项指标的生态系统服务物质量进行了区域尺度和县域尺度上的估算。结果表明：① 贵州南部地区林草生态系统年调节水量145.41×10⁸m³,年固碳量和年释氧量分别为819.96×10⁴t和1 538.48×10⁴t,年提供负离子达2.32×10²⁵个,年吸收二氧化硫(SO₂)、氟化物(F)、氮氧化物(NO_X)分别达到58.07×10⁴t、1.29×10⁴t和7.76×10⁴t,年滞尘量1.04×10⁸t,年固土总量9.07×10⁸t,年保育N、P、K以及有机质量分别为184.81×10⁴t、59.26×10⁴t、1 138.80×10⁴t以及4 045.85×10⁴t,平均生物多样性综合评价指数为54.87;② 各类生态系统服务物质量均表现出明显的空间分布趋势,整体表现为东高西低,南高北低;③ 县域尺度上,黎平县、榕江县、从江县和望谟县提供的生态系统服务物质量最多,普定县、三穗县、长顺县和丹寨县则最少;就生态系统服务供给能力而言,雷山县、望谟县、榕江县和从江县最强,兴仁县、普定县、长顺县和贞丰县则最弱。     

Eco-compensati on in Guanting Reservoir Watershed Based on Spatiotemporal Variations of Water Yield and Purification Services

Guanting Reservoir (GR) is one of the most important water sources for Beijing and neighboring regions. Due to water pollution, it was withdrawn from the system to supply Beijing drinking water; however, after a thorough treatment process, GR was made a reserve water source since 2007. To develop a comprehensive and quantitative analysis of water yield and purification services in the GR watershed, this study selected two time periods: the period when GR was withdrawn from the system supplying local drinking water and the period that it has been designated a reserve water source. The InVEST model was used to evaluate the quantities of water yields, and total nitrogen and total phosphorus outputs from 1995 to 2010 Additionally, the spatiotemporal variations of water yield services and water quality purification services in the GR watershed were analyzed. The results showed that water yield services in the GR watershed first weakened and then became stronger, but weakened overall during the years 1995 to 2010. Water yield capacity in the basin decreased from 1.89×109 m³ in 1995 to 1.43×109 m³ in 2010 (a drop of 24.0% in total). Water quality purification services also showed the same tendency. Total nitrogen output decreased from 4028.7 t in 1995 to 3611.4 t in 2010, while total phosphorus decreased from 379.7 t in 1995 to 354.0 t in 2010. Nitrogen and phosphorus purification services were enhanced by 10.4% and 6.8%, respectively. Changes in the climate and land use were the main factors which lead to the changes in the water yield service in the GR watershed. Policies intended to protect water resource have matched the varying trends of water quality purification services during different periods. On one hand, the research results provide a foundation to identify key fields for eco-compensation in the Guanting Reservoir basin. On another hand, the ecosystem service value will increase on the basis of eco-compensation criteria through setting the scenarios of returning farmland to forest and ecological protection. This method directly reflects increases in ecosystem service values that have occurred since measures to protect the ecological environment have been implemented. This method is more persuasive and feasible than using eco-compensation criteria based on regional ecosystem service values determined by land use/ coverage type. It can provide a new way to assess eco-compensation in the Guanting Reservoir basin and other regions.