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1.
Understanding the effect of biodiversity on ecosystem function is critical to promoting the sustainability of ecosystems and species conservation in natural ecosystems. We observed species composition, species richness and aboveground biomass,and simulated the competitive assemblages in a natural grassland ecosystem of China, aiming to test some assumptions and predictions about biodiversity–stability relationships. Our results show that aboveground productivity and temporal stability increased significantly with increasing species richness, and via a combination of overyielding, species asynchrony, and portfolio effects. Species interactions resulted in overyielding caused by trait-independent complementarity, and were not offset by a negative dominance effect and trait-dependent complementarity effect. Therefore, the mechanisms underlying the biodiversity effect shifted from the selection effect to the complementarity effect as diversity increased, and both effects were coexisted but the complementarity effect represent a mechanism that facilitates long term species coexistence in a natural grassland ecosystem of China.  相似文献   

2.
Assessment of vulnerability for natural ecosystem to climate change is a hot topic in climate change and ecology, and will support adapting and mitigating climate change. In this study, LPJ model modified according to features of China's natural ecosystems was em- ployed to simulate ecosystem dynamics under A2, B2 and A1B scenarios. Vulnerability of natural ecosystem to climate change was assessed according to the vulnerability assessment model. Based on eco-geographical regions, vulnerability of natural ecosystem to climate change was analyzed. Results suggest that vulnerability for China's natural ecosystems would strengthen in the east and weaken in the west, but the pattern of ecosystem vulner- ability would not be altered by climate change, which rises from southeast to northeast gradually. Increase in ecosystem vulnerable degree would mainly concentrate in temperate humid/sub-humid region and warm temperate humid/sub-humid region. Decrease in eco- system vulnerable degree may emerge in northwestern arid region and Qinghai-Tibet Plateau region. In the near-term scale, natural ecosystem in China would be slightly affected by cli- mate change. However, in mid-term and long-term scales, there would be severely adverse effect, particularly in the east with better water and thermal condition.  相似文献   

3.
Human well-being is dependent on ecosystems. Earth's mosaic of ecosystems - forests, grasslands, wetlands, streams, estuaries, and oceans - when functioning naturally, provide materials, conditions, and processes that sustain all life on this planet, including human life. The benefits that all living things obtain from ecosystems are called "ecosystem services." Some are very familiar to us, such as materials like food and timber that are essential for our lives and important parts of the global economy. What are equally important, but certainly less well recognized, are the array of services delivered by ecosystems that do not have easily assigned monetary values, but that make our lives possible. These include the purification of air and water, the decomposition of wastes, the recycling of nutrients on land and in the oceans, the pollination of crops, and the regulation of climate.  相似文献   

4.
中国自然保护区研究的现状与展望   总被引:1,自引:0,他引:1  
1IntroductionIn order to protect nature resources and natural environment, rescue the species of rare and endangered wildlife, renew vegetation, forestry and wildlife populations that are broken, nature reserves (NR) are set up. 'Nature Reserve' has been defined as a planning area of land and/or sea protected and managed specially through legal means. Nature reserves are representative natural ecosystems, natural distribution areas of rare and endangered wildlife species and natural relics wi…  相似文献   

5.
Natural ecosystems provide human society with very important products and services. With the rapid increase in population and the over-exploitation of natural resources, humans are continually enhancing the production of some services at the expense of others. This paper estimates changes in ecosystem services, and the relationship between these services in the Guanzhong-Tianshui Economic Region of China. These ecosystem changes are of great significance to the sustainable development of this economic region. The concept of production possibility frontier(PPF) is applied to evaluate the trade-offs and synergy between carbon sequestration, water yield and soil retention. Three land use strategy scenarios – planning, exploitation and protection – are applied to evaluate potential changes in ecosystem services. This study reveals noticeable trade-offs between carbon sequestration, soil retention and water yield, with synergy between carbon sequestration and soil retention. There are synergies between carbon sequestration, water yield and soil retention in the three scenarios. The protection scenario is the most favourable land use strategy for regulating ecosystem service capacity. This scenario results in the highest carbon sequestration, water yield and soil retention. The results could have implications for natural capital and ecosystem services planning, management and land use decision-making.  相似文献   

6.
From July 2008 to August 2008, 72 leaf samples from 22 species and 81 soil samples in the nine natural forest ecosystems were collected, from north to south along the North-South Transect of Eastern China (NSTEC). Based on these samples, we studied the geographical distribution patterns of vegetable water use efficiency (WUE) and nitrogen use efficiency (NUE), and analyzed their relationship with environmental factors. The vegetable WUE and NUE were calculated through the measurement of foliar δ 13C and C/N of predominant species, respectively. The results showed: (1) vegetable WUE, ranging from 2.13 to 28.67 mg C g-1 H2O, increased linearly from south to north in the representative forest ecosystems along the NSTEC, while vegetable NUE showed an opposite trend, increasing from north to south, ranging from 12.92 to 29.60 g C g-1 N. (2) Vegetable WUE and NUE were dominantly driven by climate and significantly affected by soil nutrient factors. Based on multiple stepwise regression analysis, mean annual temperature, soil phosphorus concentration, and soil nitrogen concentration were responding for 75.5% of the variations of WUE (p<0.001). While, mean annual precipitation and soil phosphorus concentration could explain 65.7% of the change in vegetable NUE (p<0.001). Moreover, vegetable WUE and NUE would also be seriously influenced by atmospheric nitrogen deposition in nitrogen saturated ecosystems. (3) There was a significant trade-off relationship between vegetable WUE and NUE in the typical forest ecosystems along the NSTEC (p<0.001), indicating a balanced strategy for vegetation in resource utilization in natural forest ecosystems along the NSTEC. This study suggests that global change would impact the resource use efficiency of forest ecosystems. However, vegetation could adapt to those changes by increasing the use efficiency of shortage resource while decreasing the relatively ample one. But extreme impacts, such as heavy nitrogen deposition, would break this trade-off mechanism and give a dramatic disturbance to the ecosystem biogeochemical cycle.  相似文献   

7.
Climate change has major impacts directly on the natural ecosystem and human society, of which the cryosphere is most easily affected be-cause of its frangibility and sensitivity. Similarly, cryosphere change has numerous impacts on the natural ecosystem and human society, which may resemble an indirect influence of climate change. These two types of impacts, in shared fields, are distinguished in space and time by effective mechanisms and processes. Climate change has positive and negative impacts on some systems, which may be adjusted by cryosphere change. These indirect and direct impacts may be distinguished, and then correct policies and measures can be made against these changes.  相似文献   

8.
Soil degradation: a global problem endangering sustainable development   总被引:4,自引:0,他引:4  
1 Introduction Soil is not only the major natural resource on which human being depends for the production of food, feed, fiber, renewable energy and raw materials, but also plays a key role in maintaining the complex terrestrial ecosystems and climate systems of this planet. Recent rapid increase in the human population is placing a great strain on the worlds soil resources. Only about 11% of the global land surface covered by the soils are being used to raise crops and livestock, in other …  相似文献   

9.
Plant growth at northern latitudes is highly responsive to the climatic changes that have occurred over recent decades. However, the sensitivity of the phasing of the seasonal cycle of terrestrial ecosystems to a changing environment remains less widely understood. We present an investigation and comparative study of large-scale changes in seasonal cy-cling of both land surface temperature and plant growth. Our results have shown trends in-dicating a marked increased towards overall plant productivity by ~3% from 1982 to 2005, reduced trends in seasonal variation at low-mid latitudes by ~2%, increased trends in sea-sonal variations at mid-high latitudes by ~7%, and an earlier phase in northern terrestrial ecosystems (~1.1 days) in parallel with changes in the phasing of surface temperatures at northern latitudes over the 24 years in this study. These shifts in annual cycles of terrestrial vegetation appear to have a distinct geographical zonality and are dependent upon latitudinal changes in climatic variables. More conspicuous changes in overall vegetation productivity and the seasonal phase of ecosystems have been observed in Eurasia compared to North America, largely because of a more rapid rise in temperature. Our results state that changing climate boosts plant growth at northern latitudes, but also alters the phase and seasonal variations of the annual cycle of terrestrial ecosystems.  相似文献   

10.
To protect the richness, diversity and uniqueness of China's ecosystems and landscapes, more than 150 national parks (named "National scenic and historic interest areas" in China), 85 national geoparks and 230 national nature reserves have been delimited nationwide. In addition, a total of 30 world heritage sites (4 mixed, 4 natural, 22 cultural), 24 biosphere reserves and 8 world geoparks have been ratified for China in a short time by the UNESCO. Unfortunately, most of these national and…  相似文献   

11.
Using the method of Constanza R, the annual value of ecosystem services of Macao was 3.302×106 US dollars in 1983, equivalent to 26.5250×106 MOP, when using the currently monetary valuation. The annual value of ecosystem services of Macao was 8.3340×106 US dollars in 2002, equal to 66.9472×106 MOP. The total globe annual value of ecosystem services was 3.3268×1013 US dollars in 1997, i.e., about 5,544.7 US dollars per capita. In Macao, the annual value of ecosystem services was only 18.8 US dollars per capita. The average ecosystem service per capita was 0.35% of the world average level. Comparing to the globe average ecosystem services level per capita, the deficit of ecosystem services of Macao is 2.44×109 US dollars for Macao population, which would require 1,069 km2 estuary to complement to the deficit, i.e., about 38 times of Macao to provide ecosystem services to reach the average level of world.  相似文献   

12.
东北松嫩平原生态系统服务价值损失的的估算   总被引:2,自引:0,他引:2  
1IntroductionEcosystems around the globe create and maintain an environment suitable for the continuation of human life. Ecosystems supply goods such as timber, pharmaceuticals, and seafood, and so provide services including purification of air and water,…  相似文献   

13.
安徽省池州市2001~2010年可持续发展动态测度与分析   总被引:2,自引:0,他引:2  
安徽池州市是国家首个生态经济示范区,近十年来,城镇化、工业化水平的快速提升加剧了其发展的风险性和不稳定性,可持续发展面临较大挑战。基于生态足迹模型,对池州市2001~2010年生态足迹供给与需求进行了时间序列测度与分析,利用灰色GM(1,1)模型对2015年、2020年人均生态足迹进行了预测。结果表明:池州市人均生态足迹由2001年的1.2458hm2/人上升至2010年的2.2483hm2/人,年平均增长11.14%,人均生态赤字由0.8445hm2/人扩大至2010年的1.8266hm2/人;居民消费水平、能源消费量与人均生态足迹相关系数分别为0.844、0.945,为生态足迹驱动因素;研究时段内,能源生态足迹年均增长速度为83.75%,明显快于生物资源生态足迹增长速度;万元GDP生态足迹由2001年的2.98hm2/万元下降至2010年的1.20hm2/万元。预测2015年人均生态足迹为3.2336hm2/人,生态赤字将增至2.7926hm2/人;2020年人均生态足迹为4.4896hm2/人,生态赤字将扩大到4.0308hm2/人。针对池州生态不安全的现状,从减少能源消费、改变消费方式、提高农作物单产等方面提出了减少生态足迹的政策建议。  相似文献   

14.
An emergy-based environmental accounting of Mongolia is presented based on the data from 1995 to 2012. By calculating natural and economic inputs and a series of emergy indicators, this paper discusses Mongolia’s resource use structure, economic situation, trade status and societal sustainability. The results show that the total emergy use for Mongolia changed from 2.83×1022 sej in 1995 to 4.96×1022 sej in 2012, representing a 75% increase over the 18 years of this study, yet its emergy per capita remains one of the lowest in the world (1.74×1016 sej/capita). The emergy money ratio (EMR) of Mongolia during 1995–2012 decreased from 1.99×1013 sej/USD to 7.75×1012 sej/USD, which indicates that the power of a dollar for purchasing real wealth in Mongolia was declining, while the relatively high absolute values compared to its trading partners and even the world average EMR suggests that Mongolia is continuing a trade disadvantage. Mongolia’s emergy exchange ratio is increasingly less than one to the point that in 2012 the ratio was 0.3 suggesting that the exported emergy was over 3.3 times greater than the imported emergy. The growing dependence on imports and the dramatic increase in exports suggests that Mongolia’s economy is increasingly vulnerable to downturns in the world economy.  相似文献   

15.
Zhang  Zhengyong  Liu  Lin  He  Xinlin  Li  Zhongqin  Wang  Puyu 《地理学报(英文版)》2019,29(1):101-114

Mountain glaciers, which perform a unique and irreplaceable ecological service, provide the material basis and characteristic cultural foundation of the ecological environment and sustainable socio-economic development in arid areas. However, few studies have estimated the service value of glaciers in regulating ecological environment and providing human welfare. According to the statistics of the First and Second Chinese Glacier Inventory (FCGI/SCGI), this study analyzed the variations in glacier area and ice volume in the Tianshan Mountains in China and modeled the ecosystem service function of mountain glaciers. The service value per unit area and equivalent factor methods were combined to determine the annual value of the ecological service provided by glaciers in the study area. The results show that: (1) In the period 1970–2010, the glacier area decreased by 1274 km2 (the ratio of area shrinkage was 13.9%) and the annual average decrease in ice volume was 4.08×109 m3. The increase in glacier area at high altitudes (> 5200 m) may be due to the fact that glacier accumulation caused by increasing precipitation is greater than glacier melting caused by rising temperatures. (2) The annual value of the ecological service provided by glaciers in the study area is 60.2 billion yuan. The values of climate regulation, hydrological regulation, and freshwater resource supply account for 66.4%, 21.6%, and 9.3% of the total value respectively. The annual value of the ecological service provided by hydroelectric power is 350 million yuan. (3) From a comparative analysis of the glaciers, forest, grassland and wetland ecosystems, the supply of freshwater resources/physical production and ecological regulation represent the main contributions of the four types of system, and the ecosystem service value of glaciers per unit area is higher than that of other types of ecosystem. This research will improve the understanding of the impact of glaciers on human welfare and maintenance of the ecological environment and will promote the ecological security of the cryosphere, environmental protection, and the sustainable use of resources.

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16.
蔡人群 《热带地理》1997,17(2):101-107
中国改革开放以来,香港、澳门与珠江三角洲之间已逐渐形成一个联系密切、优势互补的经济区域。本文分析了该经济区的形成条件及其在中国、亚洲的地位和作用。并建议开展全经济区协调性规划,处理好区内经济分工,香港、澳门与珠三角主要城市的协调发展,并建设统一的区域性基础设施,使经济区发展更上一层楼。  相似文献   

17.
青海湖高寒湿地生态系统服务价值动态   总被引:1,自引:0,他引:1  
以1987、2000、2010年3个时期的TM影像为主要数据源,基于对中国生态系统单位面积服务价值的生物量修订,研究了青海湖湿地生态系统服务价值的动态特征。结果表明:1987-2010年青海湖高寒湿地总生态系统服务价值增加到了232.34亿元,年均增加0.18亿元,其中,湖泊、高寒草甸、高寒沼泽和温性草原生态系统服务价值是其主要构成部分。人类活动行为和气候变化驱动着其生态服务价值动态。研究区生态服务功能以水文调节、废物处理、气候调节、维持生物多样性功能为主,此4种功能的价值占到了总价值的70%以上。近24年里除原材料生产功能外,其他各项生态系统服务功能均在不同程度地增加,生态服务价值波动最大的是水文调节、废物处理和气候调节功能。  相似文献   

18.
The use of untreated surface water for domestic purposes has resulted in the infection of some people by guinea worm and other water borne diseases in the Northern Region of Ghana. The aim of this study is to assess the current groundwater quantity and quality conditions in the 7,820 km2 Daka catchment and project the water demand in 2025. Results of groundwater analyses generally show good water quality for domestic use. Borehole analyses indicate that the catchment’s groundwater system can be characterized by a regolith aquifer underlain by a deeper fractured rock aquifer in some areas. The current per capita water demand is estimated at 40 l/day although 60 l/day is the desired amount, indicating that with the current population of 363,350, the projected water demand for the communities is 21,800 m3/day. With a projected population of 555,500 in 2025, an expected 33,300 m3/day of water is required. The estimated optimum potential groundwater available for use in the catchment is 154 × 106 m3/year (4.24 × 105 m3/day). However, the current total groundwater abstraction is only 8,876 m3/day or 2% of the optimum. In comparison, the projected total current and 2025 water demands are only 5 and 8%, respectively, of the optimum potential groundwater available for use in the catchment. In addition, only 1,780 m3/day (0.65 × 106 m3/year) or 0.06% of the average annual flow of 1,016 × 106 m3/year of the Daka River is treated for domestic use. These figures reveal that a significantly very large water resource potential exists for both surface and groundwater development in the Daka catchment. It is suggested that their development should proceed conjunctively.  相似文献   

19.
中国西北水资源利用及生态环境安全   总被引:1,自引:1,他引:0  
1 Introduction In the 21st century, water resources will become the international and strategic resource instead of petroleum (Kang et al., 1994a, b). At present, the freshwater resources crisis all over the world has made people aware that although water…  相似文献   

20.
Downstream hydrologic effects since the closure of Glenbawn Dam, a large dual-purpose storage for water conservation and flood mitigation, include: (i) a reduction in mean annual runoff of about 21 × 106 m3; (ii) a change in the probability distribution of mean daily flows involving a truncation of flows >;8 × 106 m3 d?1, a much reduced frequency of flows >7 × 105 m3 d?1 and an increased frequency of flows <7 × 105 m3 d?1; and (iii) a reduction in flood magnitude of at least 80 per cent for all probabilities of exceedance. From suspended sediment samples collected before and after dam closure, sediment trap efficiency has been estimated at 99 per cent.An accommodation adjustment of the channel has occurred upstream of the first unregulated tributary because the bed is armoured, the banks are well vegetated, some bedrock and concrete controls are present and all regulated releases are incompetent to transport the bed material. Immediately downstream of the first unregulated tributary, the channel has contracted by up to 45 per cent and degraded by up to 69 per cent during lateral migration. Further downstream no channel changes were recorded although the bed material has progressively coarsened over time.  相似文献   

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