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1.
为了研究太原市近十年来的生态系统服务价值变化情况,通过分析2002-2011年间太原市土地利用变化的幅度和动态度,以Costanza的生态系统服务价值计算公式和谢高地等人的单位面积生态服务价值表为基础,计算出太原市在10年间生态系统服务价值的变化,研究表明:太原市2002-2011年间生态系统服务功能总价值量基本稳定,草地、林地和水利的生态服务价值都有了显著地提高,说明太原市在保持经济、社会和生态和谐发展方面作用显著。  相似文献   

2.
本文以大庆市为研究区,依据2001年和2009年的土地利用数据,从生态系统服务功能角度,运用Costanza的方法,结合谢高地修正的我国生态服务价值当量因子表,定量研究了土地利用变化引起的生态系统服务价值变化量。结果表明:2001~2009年间,研究区林地和城乡居民点及工矿用地面积增加,其余土地利用类型面积均有减少,其中林地的面积变化量最大。土地利用变化引起了研究区生态环境的变化,对生态系统服务价值也产生了一定的影响,大庆市9年间生态系统服务价值增加了41170.55万元,各单项服务功能价值中,其生态系统所提供的水源涵养、废物处理和食物生产等3项生态服务功能下降,其余6项生态系统服务功能均有不同程度的升高;从不同土地利用类型的生态服务功能看,湿地和水域的生态服务功能较强,只有林地的生态系统服务价值是增加的。  相似文献   

3.
采用生态服务价值法对大庆市1996-2007年土地利用变化引起的生态服务价值变化进行了研究,结果表明土地利用类型面积变化为:草地耕地水域未利用地林地建设用地。耕地、林地、水域、建设用地呈增加态势,而其他地类则减少。其中水域增幅最大,达42.31%;牧草地减幅最大,达4.13%。11年间大庆市生态系统服务价值总量增加324506.61万元,主要得益于水域面积的增加,耕地、林地的增加对生态系统服务价值量的增加也起到了一定的作用。这表明大庆市生态建设取得了成效,生态环境质量有所提高。  相似文献   

4.
以大连市甘井子区为研究对象,基于GIS技术结合土地利用动态度模型和生态系统服务价值估算方法,分析2000、2003、2006和2009年4个时序的大连市甘井子区土地利用数据,研究其土地利用变化对生态系统服务价值的影响。大连市甘井子区作为典型的城市边缘区,对其进行研究,可以得出城环边缘区的土地利用变化对生态系统服务价值的影响特征,对城市边缘区的土地利用规划与整理提供科学价值。结果表明,大连市甘井子区2000~2009年土地利用发生明显变化,耕地、园地、未利用地面积减少,建设用地、林地、水域面积有所增加,耕地土地利用动态度为-6.10%,建设用地土地利用动态度为1.27%;2000~2006年甘井子区生态系统服务价值呈现增加态势,6年间增加2 600.91万元,2006~2009年呈现减少态势,3年间减少679.36万元;除林地外,其他土地利用敏感性指数均小于1,生态系统服务价值对价值系数缺乏弹性。  相似文献   

5.
计算得到2013年安徽省单位面积生态系统服务功能价值表,估算2009~2013年庐江县土地生态系统服务价值,并分析土地利用/覆被变化对其生态服务价值的影响。研究表明:(1)土地利用/土地覆被变化主要表现为除耕地以外的非建设用地的减少,而建设占用是这种减少的最主要原因,尤以2012年度为甚。(2)生态系统服务总价值逐年递减,总减少量约为5490万元,年均减少约1373万元。其下降主因是水域、湿地、林地的减少。(3)生态系统服务功能价值主要集中在水域、耕地和林地之中。  相似文献   

6.
由土地利用变化导致的生态系统服务价值的变化可以作为一个反映土地利用变化环境效应的重要 量化指标。该文参考谢高地等人提出的单位面积生态服务价值系数,对涞水县2001~2010年的土地利用变 化及其对生态系统的影响和驱动因素进行了分析研究。结果表明,2001~2007年和2007~2010年土地利用 类型变化差异较大。2001~2007年,耕地面积有大幅减少,林地、草地面积大幅增加,2007~2010年,耕 地、草地、居民点及工矿用地面积增加明显,园地、林地、滩涂和裸地减少;2007~2010年的土地利用变 化率明显高于2001~2007年;由于林地、滩涂面积的减少和居民点及工矿用地面积的增加,使得整个研究 期生态系统服务价值净减少4 024.47万元;整个研究期间内各项生态系统服务功能都出现不同程度的衰 退。农用地和非农用地经济生态位在研究期内呈波动变化,导致其两者的差值也呈波动变化。驱动因素分 析表明,前期政策因素影响较大,后期社会经济指标对生态系统起负向作用。由于该区特殊的地理位置和 相对薄弱的经济基础,该区域迫切需要处理好经济发展与生态环境的关系,提高土地利用集约度,合理调 整产业结构,进一步完善生态补偿机制等以实现区域生态建设与经济发展互促双赢。  相似文献   

7.
该研究以北京市昌平区1993、2001、2007年三期的土地利用现状图为基础,利用GIS技术计算了各种土地利用类型的面积变化和相互之间的转换情况,了解到各种土地利用类型面积变化的原因。分析了土地利用类型生态服务价值的损益。研究表明:(1)1993年到2001年,土地利用类型之间的转换较为频繁,2001年到2007年,变化程度相对较少,但各种用地类型向建设用地转换的面积较高。(2)昌平区生态系统服务价值总体稳定,但是从1993年到2007年,生态服务价值总值持续降低,幅度不大。由1993年23.9亿元,降低到2001年的22.7亿元,2007年又降低到21.6亿元。(3)在昌平起主要生态作用的用地类型是林地,并且其生态服务价值总值和比例是增加的,耕地面积的减少是该区生态系统服务功能丧失的最主要原因。今后应严格控制耕地向建设用地的转换。加强对昌平区生态和环境保护力度,促进其经济社会可持续发展。  相似文献   

8.
近年来,随着经济社会加速发展与新农村建设的不断深入,在北京这样的大都市中农业的生产功能逐渐被弱化,农业的生态功能越来越凸显重要作用,估算农业的生态服务价值逐渐成为学术界研究的热点。目前国内主要是参照谢高地提出的中国陆地生态系统单位面积服务功能价值表,即用全国生态系统的平均服务价值来估算不同区域的农业生态服务价值,这与北京的社会发展水平、城市定位及都市型现代农业的功能定位是不符合的,因此是不太恰当的。文章以北京农业生态服务价值评估为研究目标,在全国生态系统服务价值评估体系的基础上,对北京市300多位具有相关专业背景的学者进行问卷调查,对中国生态系统单位面积生态服务价值当量表进行有依据的修改,制定出更适合北京区域的不同土地利用类型生态系统服务评估单价体系,并以此表为依据测算了2013年北京农业生态服务价值的理论值与现实值。研究发现北京的农业生态服务价值十分巨大,文章提供了一种更符合北京生态系统状况与经济发展水平的农业生态服务价值评估方法,可以用于已知土地利用面积的农业生态服务价值估算,能够在较短时间内获得较为精确的结果。  相似文献   

9.
陕西省榆林地区生态服务价值变化研究   总被引:1,自引:0,他引:1  
引用陕西榆林地区土地利用动态变化研究的最新成果获取1986年,1996和2000年3个不同时段的土地利用变化数据。使用生态价值系数(VC)计算出本研究区生态服务价值,并使用敏感度指数(CS)对所选的VC值进行验证。结果表明,榆林地区1986-2000年间生态系统服务总价值从274.66亿元增加到283.67亿元,净增加9.01亿元,总体呈上升趋势。但在1996-2000年的四年间生态系统服务总价值表现出降低趋势,年下降率为0.02%,这主要是由于草地部分沙化、水域和沼泽湿地面积的明显减少。CS检验说明本文所选VC值较为合理。  相似文献   

10.
随着经济的快速发展,土地利用变化频繁,生态问题日益凸显。为了探究土地利用与生态系统的密切联系,为生态建设提供理论依据,以内蒙古赤峰市农牧交错带为研究区,基于1997年、2004年和2011年的三期TM影像数据,运用土地利用动态度分析土地利用类型变化,并参照中国陆地生态系统服务价值的计算方法估算出研究区的生态系统服务价值。结果表明,研究区3期的耕、林、草面积均占土地总面积的90%左右;土地利用类型变化明显,在1997~2011年耕地面积先减少后增加,林地面积一直持续增加,草地面积不断减少;研究区的生态系统服务价值呈增长趋势,草地和林地对生态系统服务价值贡献最大,占总价值的85%左右;各土地利用类型的敏感性指数均小于1,说明研究区生态系统服务价值对所采用的生态服务价值系数缺乏弹性,研究结果具有一定可信度。土地利用变化对生态系统服务价值具有直接影响,科学合理利用土地对生态系统具有重要意义。  相似文献   

11.
The theory of demand and supply implies a positive relationship, or “price transmission” between the prices of products at different stages of manufacturing. This relationship was investigated with quarterly prices of softwood stumpage in the US South, and national prices of forest products, from 1977 to 2002. All prices, net of inflation, were found to be nonstationary and there was no evidence of co-integration between prices. Vector autogressive models, augmented by Granger causality tests and multiplier analysis showed that there was a one-to-one permanent positive response of the southern sawtimber stumpage price to a permanent change in the national lumber price. There was also a one-third permanent positive response of the national paper price to a permanent change in the national pulp price. There was no relation between regional pulpwood prices and national pulp or paper prices. When price transmission was significant, the full adjustment took about 2 years.  相似文献   

12.
Owners, local residents, government, and conservation organisations can express divergent preferences in the development and management of local woodlands. The perceptions of these four groups were examined, in the context of three community woodlands in Eastern England, using an ecosystem function framework. In a pilot study, residents were able to allocate a relative importance to woodland ecosystem services which were then related to “regulation”, “habitat”, and “production” or “information” functions. However residents also placed importance on negative services or “dis-services” associated with the woodland ecosystem. Therefore a fifth category of “dis-services” was included in the main survey which included 84 local residents, three woodland owners, three government institutions, and six representatives from conservation groups. Each of the four groups placed greatest importance on services associated with habitat (16–39% of the total importance) and information (30–50%) functions suggesting, in this example, mutual interest in the use of woodlands as a habitat or recreational resource. By contrast a potential area of difference was the particularly high importance placed by one owner on dis-services such as fly tipping. In addition the woodland owners placed higher importance (10–20%), than local residents and conservation groups (7–9%), on the productive services of the wood. This suggests a need for communication when production-related operations affect recreation. The ecosystem function framework appears to be a useful approach for highlighting potential tensions and areas of mutual interest in the management of semi-natural ecosystems.  相似文献   

13.
The primary objective of this paper is to examine changes in the level of output, prices and exports of major export crops resulting from the Structural Adjustment Program (SAP) in Nigeria. THere two main sources of data: the Central Bank of Nigeria (CBN) through its annual reports, Economic and Financial Review, and the Nigerian Federal Office of Statistics (FOS) through its Trade Summaries. Although the SAP led to appreciable increases in output and producer prices, its effects on exports were insignificant. The implications of these for the implementation of the program are explored.  相似文献   

14.
China is one of the largest wine importing countries in the world and is poised for continued import growth in the future. Increased wine purchases throughout China have given rise to persistent fraud where fake wines are packaged and sold with counterfeit contents and labels. For exporting countries like France, counterfeit wines displace market share, damage foreign brand reputation, and cause distrust in consumers who are aware of counterfeiting problems throughout the country. We examine the impact of fraudulent wine events (as measured by negative media reports) on Chinese wine demand differentiated by supplying country. We employ the Rotterdam demand system and a switching regression procedure to estimate import demand and compare results across different media variable specifications. Results consistently show that negative reports disproportionately affect French wine regardless of how the media variable is specified. This is not surprising because most fraudulent events involve French wine counterfeits.  相似文献   

15.
In recent years earthquakes and their secondary hazards have claimed the largest number of lives of all large natural disasters. Some of the world’s most earthquake-prone zones are also areas of high population density. The impact is magnified by vulnerability factors including non-enforcement of building codes, knowledge gaps, urban poverty and poor governance capacity to manage and reduce earthquake risks. Poor security of land tenure and property rights increases the vulnerability of people and affects their ability to respond to natural disasters.Earthquake recovery and reconstruction provides very significant challenges for land agencies, with these challenges differing from one country to the next due to differences in the local context. Drawing on contrasting case studies in Haiti, Nepal and New Zealand this paper identifies the common post-earthquake land administration functions and challenges that may apply to many contexts. These lessons provide land agencies and other key stakeholders with a summary of the challenges an earthquake poses for land administration at different post-disaster stages. We also discuss the policy and regulatory, institutional, operational and preparedness lessons for land administration. From these lessons we propose a framework for evaluating the earthquake-responsiveness of a land administration system. This framework can be used by a land agency in an earthquake prone region, or where an earthquake has recently occurred, to assess what challenges to land administration might occur in the event of an earthquake, and the preparedness of their land administration system.  相似文献   

16.
This paper analyses poverty and calorific undernourishment in the Indian state of Gujarat, where high and market‐led industrial growth has resulted in rapid economic improvement. The study is carried out through a combination of secondary and survey‐based data. We conclude that the neoliberal agenda of uncontrolled, outward‐looking growth has not resulted in significant reduction of poverty or malnourishment in rural areas. Furthermore, while land ownership is officially used as a proxy for wealth distribution, class position appears a better predictor of poverty status in the rural areas than landownership per se. At the policy level, there is a need to revive the agrarian economy and create new non‐agricultural assets, and the primary focus in the state must shift to the distribution of created assets rather than a single‐minded focus on growth.  相似文献   

17.
Fieldwork shows that many Sierra Leonean producers do not receive the official producer price for their coffee and cocoa, due to the concentration of buying stations, credit relations, the small quantities offered for sale, and the lack of marketing knowledge of the numerous and unorganized farmers. To the traders underpayment may seem economically justifiable to a certain extent, but to the farmers it means poverty and debt. A new village marketing centre project aims at remedying this situation and has already led to higher prices. Although no longer allowed to take their "just" share from the producers, traders are still willing to deal with the new centres.  相似文献   

18.
The values ascribed to industrial tree plantations are often controversial. Hence knowledge of their perceived impacts is important for improving their integration in rural landscapes. In 2016 we conducted household surveys with 606 respondents living in villages adjacent to acacia, teak and pine plantations across three islands in Indonesia (Java, Borneo, Sumatra). Results show that perceptions toward pine and teak plantations tend to differ from those toward acacia pulpwood plantations in several ways. Pine and teak plantations are perceived to have a higher number and variety of benefits and services, a higher number of positive impacts, a better environmental record, and to present more opportunities to local people for use of plantation land and products for improving rural livelihoods. In addition, we find that villagers around acacia pulpwood plantations tend to seek economic development and infrastructure to open up remote areas, yet their expectations were often only partially met. Recommendations from our analysis include: the role of the State in plantations must be clarified and potentially reinforced; the role of institutions as intermediaries is fundamental; and contributions by communities to design of management plans should be accommodated.  相似文献   

19.
This paper tests the ‘systems of innovation’ hypothesis for a selection of crops in Ghana and Burkina Faso that have shown significant growth in production over an approximately 20-year period. The question is whether such growth can only occur if supported by a system of innovation. Using two indicators (a common understanding on objectives and priorities, and a high level of interactivity), we find little evidence for the existence of anything that might be considered a high functioning system of innovation.  相似文献   

20.
Large‐scale tree plantations in high rainfall upstream areas can reduce fresh water inflows to river systems, thereby imposing external costs on downstream irrigation, stock and domestic water users and wetland interests. We take the novel approach of expressing all benefits and costs of establishing plantations in terms of $ per gigalitre (GL) of water removed annually from river flows, setting upstream demands on the same basis as downstream demands. For the Macquarie Valley, a New South Wales sub‐catchment of Australia’s Murray‐Darling Basin, we project changes in land and water use and changes in economic surpluses under two policy settings: without and with a policy requiring permanent water entitlements to be purchased from downstream parties, before plantation establishment. Without the policy, and given a high stumpage value for trees ($70/m3), upstream gains in economic surplus projected from expanding plantations are $639 million; balanced against $233 million in economic losses by downstream irrigators and stock and domestic water users for a net gain of $406 million, but 345 GL lower mean annual environmental flows. With the policy, smaller gains in upstream economic surplus from trees ($192 million), added to net downstream gains ($138 million) from sale of water, result in gains of $330 million with no reduction in environmental flows. Sustaining the 345 GL flow for a $76 million (406–330) reduction in gains to economic surplus may be seen to cost only $0.22 million/GL; but this is much lower than the market value of the first units of that water to agriculture and forestry.  相似文献   

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