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1.
This study looks at the impact of subdivision and sedentarization of pastoral lands on wildlife numbers and production in a savanna ecosystem of southern Kenya. The study uses aerial counts over a period of 33 years to compare changes in wildlife populations on two adjacent and ecologically similar Maasai group ranches. During the period under study, one group ranch was subdivided and settled. The other remained communally owned under shifting seasonal use. Wildlife populations decreased sharply on the privatized ranch following subdivision and increased steadily on the adjacent ranch where pastoralists continued mobile pastoralism. The results of multivariate analysis show that sedentarization and settlement distribution accounts for wildlife declines on the subdivided ranch. Both the direct displacement of wildlife and the reduction in grass production following a switch from seasonal to permanent grazing associated with sedentarization are discussed as causes of wildlife loss. Given the demand for title deeds among pastoralists to counter land losses, the resulting sedentarization is likely to become the biggest threat to wildlife in the East African savannas.  相似文献   

2.
Sacred natural sites are considered an additional pillar for biodiversity conservation, next to the protected areas network. However, sacred landscapes are not primarily conservation areas, but exist for cultural and social reasons. To evaluate their strengths and weaknesses as community-based conservation areas, a thorough understanding of the underlying values, institutional arrangements, and outcomes is required. Here, I use institutional economics for a meta-analysis of publications on sacred natural sites to identify potential conflicts in their maintenance, and to analyze institutional arrangements to solve these conflicts. I show that most sacred natural sites resemble common-pool resources and that many design principles that are linked to common-pool resources are also found in traditional institutions managing sacred places. Design principles are no blue-print solution but they may guide future research to identify locally robust institutional arrangements that are linked to the ecological integrity of sacred natural sites.  相似文献   

3.
 农林复合生态系统是一种人工自然复合生态经济系统,对植被恢复和持续发挥土地生产力,具有极为重要的生态经济价值。在综述前人研究的基础上,论述农林复合生态系统生态学原理及生态经济功能的一系列问题:解析农林复合生态系统的定义和基本特征;归纳农林复合生态系统构建的生态学原理和生态经济功能,其中着重说明农林复合生态系统结构组分选择的原则、依据和结构优化的标志,在生态过渡区构建农林复合生态系统,可发挥双向生态缓冲功能。认为:今后农林复合生态系统的研究,应以受干扰较轻的自然生态系统为参照模式,研究农林复合生态系统组分间的生态关系,生物组分生态和谐机制,小尺度的空间异质性对局部生境植被恢复与构建的生态效应,并加强农林复合生态系统的生态定位研究。  相似文献   

4.
自然冷贮藏系统中一维动态蓄冷过程的初步研究   总被引:1,自引:0,他引:1  
冰动态蓄冷问题的实质是伴随有潜热释放或吸收的移动界面导热问题。由于已有的文献对自然冷贮藏系统的热力学分析涉及较少,而冰融化与凝固过程中传热规律的研究又是大规模制冰的关键,故该文从传热学角度出发,将自然冷贮藏系统中蓄冷水箱进行简化,通过试验得到相变界面随时间变化的实际曲线。在理论计算中,考虑冰层和水的导热量与水的相变潜热释放量之和等于冰层与外界的对流换热量建立数学模型,得到冰厚随时间变化的理论关系曲线。与实际曲线比较表明,理论模型能够反映冰一维动态蓄冷的实际进程。  相似文献   

5.
This paper describes the use of geomorphologic knowledge for resource management in rural areas of less developed countries. Specifically, we discuss the contribution of geomorphologic mapping (coupled with landscape knowledge) to natural resource management using geographic information systems (GIS) and remote sensing techniques. We describe a case study conducted at Nuevo San Juan Parangaricutiro, an indigenous forest community in the Paricutin area, in Michoacan, Mexico.The analysis described in this paper was used to improve the mapping of forest quality units, and to explore the relationships between land suitability and land utilisation requirements for potential diversification of economic activities in the indigenous community. The approach proved useful for the management of natural resources and was made operational by the actual managers of the resources. The community of Nuevo San Juan was granted the green certification (Smart Wood) by the Forest Stewardship Council (FSC) and produced a fully automated resource management plan.  相似文献   

6.
我国自然保护区生态旅游业问题诊断与对策研究   总被引:4,自引:0,他引:4  
魏遐 《水土保持研究》2003,10(3):130-133
我国自然保护区开展生态旅游业具有重要的意义,是自然保护事业和旅游业可持续发展的需要.阐述了现阶段自然保护区开展生态旅游所面临的问题,即开发建设、经营管理、游客活动三个方面的问题,并对这些问题进行了深入分析,最后提出保护区生态旅游业发展的对策及其解决方法.  相似文献   

7.
热管技术在自然冷源蓄冷中的应用   总被引:1,自引:4,他引:1  
为实现无能耗、无噪音、方便快捷有效地贮存冬季自然冷源,基于热管技术,开发建成了一套热管模组自然冷源蓄冷系统,建立了单管制冰过程的一维传热模型,并对理论进行了试验验证。结果表明:单管制冰半径与制冰时间呈幂函数关系,修正后的解析解能够可靠预测实际制冰情况。研究成果为热管模组间管间距的设计和蓄冷制冰量的预测提供了有效的理论依据。  相似文献   

8.
9.
国土空间生态保护修复是维护国家生态安全格局的重要保障,科学划定与管控保护修复关键区对维持区域生态系统功能与可持续发展具有重要意义。该研究以福建上杭县作为典型研究案例区,在综合生态系统完整性、系统性与生态效益的基础上,构建了"重要性-脆弱性-服务价值"(I-F-V)的多维生态系统测度框架,进而分析了区域生态系统的多维特征、测度因子间的权衡与协同关系,运用空间聚类(分组分析)划定了生态保护与修复空间,并基于各分区的空间分异性及生态系统结构特征,提出分区管控措施。结果表明:1)上杭县生态系统具有较强的空间异质性,整体上呈现重要性较高、脆弱性程度低、服务价值较高的空间分异格局;2)上杭县各生态系统测度因子间协同与权衡关系并存,综合重要性、脆弱性和服务价值之间均为协同关系,生态系统保护与修复区域可能存在高度重叠;3)上杭县可划分为III-I-V(中等重要-一般脆弱-极高价值)、III-III-V(中等重要-中等脆弱-极高价值)、III-II-V(中等重要-较为脆弱-极高价值)、III-III-IV(中等重要-中等脆弱-较高价值)、II-III-I(较为重要-中等脆弱-低价值)和IV-I-I(高度重要- 一般脆弱-低价值)6个分区,其中,III-I-V和III-II-V两个分区面积较大,是区域发展的生态系统功能基底,各分区所在的土地覆被类型构成也存在明显的空间异质性,林地、灌丛、耕地和园地属于优势土地覆被类型;4)依据生态保护与修复措施将研究区进一步划分为生态保护区(生态保育区、绿色发展区、适度开发区)和生态修复区(生态修复区、保护修复统筹发展区)。研究结果可为区域国土空间生态保护修复规划与建设、生态安全格局维护提供较为科学、全面的研究思路和实践借鉴。  相似文献   

10.
This paper examines the ways in which a policy aiming to improve both use of an extensive dryland natural resource, and the well‐being of rural peoples in Botswana, has impacted on the environment and upon indigenous land‐use activities. The impacts of the Tribal Grazing Land Policy (TGLP) have been spatially and temporally variable. Previous assertions about its contribution to desertification may have been overstated, although environmental changes have certainly resulted from policy impacts. Effects upon traditional indigenous population coping strategies for environmental variability are considered both in terms of subsistence activities and the ability to respond to drought events. It is concluded that the policy has not met its environmental, pastoral production or societal objectives, largely because it was founded on unestablished assumptions. Large‐scale environmental degradation and desertification, however, cannot yet be attributed to the TGLP, but it can be contended that the policy has reduced both environmental and societal resilience to natural environmental variability. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

11.
昌都地区生态系统服务功能价值评估   总被引:2,自引:0,他引:2  
生态系统服务功能是生态学、生态经济学研究的热点问题,对于促进生态系统可持续管理具有重要作用.昌都地区属于青藏高原的一块典型高原生态脆弱区,对其进行生态系统价值评估有利于其生态和经济的可持续发展.运用谢高地等人制定的中国陆地生态系统的价值评估方法,对昌都地区的生态系统服务功能价值进行评估.结果表明:该区各类生态系统的总价值为105 435.12×106元,是当年GDP的37倍.各生态系统类型中林地价值最高,其次是草地.直接利用价值(包括食物生产、原材料生产、娱乐文化功能)每年约为13 567.38×106元,间接利用价值(包括气体调节、气候调节、土壤形成与保护等)约为59 412.5×106元,间接利用价值远远大于直接利用价值,说明间接利用价值对人类的贡献和作用与提供产品本身一样重要.  相似文献   

12.
African lion (Panthera leo) populations are in decline throughout most of Africa, but the problem is particularly acute in southern Kenya, where Maasai people are spearing and poisoning lions at a rate that will ensure near term local extinction. Lion killing is shaped by Maasai perception of livestock depredation, socio-economic factors, and the complex relationship between Maasai and conservation. These all affect tolerance for lions and consequently Maasai behavior towards conservation initiatives and carnivores in general. We used an in-depth quantitative questionnaire and participatory rural appraisals (PRAs) to identify the social and ecological predictors of lion killing and to investigate the effect of a compensation scheme on individual tolerance. Individuals who lose a greater proportion of their livestock to predators relative to their overall livestock loss, those affiliated with an evangelical church, and those who mainly sell rather than accumulate livestock all reported a higher propensity to kill carnivores. The future of carnivore conservation in this region depends on a better understanding of the nuances of human–carnivore conflict and a concerted effort to address appropriate cultural and community-level institutions, chiefly by providing economic benefits to local people who engage in positive conservation activities.  相似文献   

13.
This study is about the diversification of livelihood strategies and the interaction of farmers' livelihood with landscape change in Zhongzhuang small watershed, Pengyang County in Ningxia Autonomous region located in the Loess Plateau, western China. Farmers' livelihoods and landscape patterns during 1978–2007 in Zhongzhuang were analysed. In different stages, diverse limiting factors were discovered behind the diversification process of livelihood strategies. Before 1978, ‘planned economy’, ‘production team organization’, strict ‘household registration system’ and the scarcity of livelihood assets were the main factors restricting the diversification of livelihood strategies. From 1978 to 1993, the reform and open policy provided opportunities for local people to diversify their livelihood strategies, but livelihood strategies based on crop production still took an important role in their life. From 2000 to 2007, national policies brought assistance to help local farmers diversify their agricultural activities. However, the insufficient and incomplete credit and insurance market and lack of skill were the main factors constraining non‐farm activity diversification. Meanwhile, through analysis of the links between livelihood strategies diversification and landscape pattern change, we found that diversification of farmers' livelihoods contributed to the recovery of the landscape. Finally, using this relationship, steps for future landscape restoration is proposed, which provide a new view of landscape restoration research in the Loess Plateau. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

14.
This paper describes the environmental problems facing the development of Kenya's Arid and Semiarid lands (ASAL) today. The problems arise because of a rapidly declining resource base in the ASAL as a result of overexploitation and misuse, following basic land use conflicts. The extent of the overutilization or resource damage is not well known and varies a great deal from one agroecological zone to another and from resource to resource in the ASAL; those most affected include: soil, water, range, forest, livestock and wildlife. As a result of increased population growth in the ASAL, these resources are under stress. This paper argues that many of the environmental problems in the ASAL cannot be solved if the development programme does not address the needs of the people who live in the ASAL. There is a need to shift the objective of ASAL development from a preoccupation with economic growth and the idea that the ASAL should make a contribution to GNP through interregional trade and export to sustainable development that enables the communities in the ASAL to support themselves at as good a standard of living as possible. The last part of this paper outlines a strategy to promote such sustainable development.  相似文献   

15.
毛乌素榆林沙地农林复合经营模式与效益研究   总被引:1,自引:0,他引:1  
根据榆林风沙滩地的自然、经济、社会条件,进行了沙漠化土地综合治理与生态农业开发试验,建立了10种农林复合经营示范模式,总结分析了农林复合经营开发所取得的生态、经济和社会效益,并针对存在的问题提出了对策,为毛乌素沙地综合治理与开发提供了借鉴。  相似文献   

16.
The relationships between pastoralists, livestock, and the environment in dryland Africa are complex. Over the last half‐century dominant narratives have portrayed pastoralists and their livestock as being responsible for ‘over grazing’ and ‘degradation’ without attention to how resource availability and cattle mobility are spatially distributed and temporally variable. The objective of this study is to test hypotheses on the nature, magnitude, and extent of the spatially and temporally explicit interactions between the density and distribution of pastoral cattle and resource availability. The study relies on coupling remotely sensed vegetation indices with cattle Global Positioning Systems (GPS) collar data for a pastoral community in southern Kenya. Data are temporally stratified in order to account for seasonal effects. Across seasons, there is a positive relationship between cattle mobility and resource availability with the trend more pronounced during drier periods, reflecting a strategy of increased resource access. The relationship between cattle density and vegetation reveals a strategy of increased resource utilization during wetter periods. The spatiality of high‐density areas differs by season, revealing that cattle intensively utilize different parts of the landscape at different times. Areas closest to the household are consistently impacted by cattle across all seasons. These findings have implications on how the savanna vegetation may be impacted as trends towards sedentarization and reduced pastoral mobility continue. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

17.
A lack of appreciation of Kenyan farmers' knowledge and their perceptions of soil erosion and soil conservation measures was the reason for low adoption of recommended technologies. This research was carried out to identify the criteria that farmers used to distinguish farm‐types and to use these types to evaluate different knowledge levels and perceptions of soil erosion and existing soil and water conservation (SWC) measures in the Central Highlands of Kenya. Community meetings and semi‐structured household surveys were carried out in a small catchment, with 120 households. Results partly support the idea of using farmer‐developed criteria to distinguish among land managers with reference to a farm‐type classification. Criteria distinguishing three classes of land managers (good, moderate and poor) were significant with regard to the following land husbandry practices: use of hybrid or recycled seed and use of organic and/or inorganic fertilizers. Farmers were aware of on‐going soil erosion and of several erosion control measures. Whereas a majority of farmers preferred grass‐strips as a SWC measures, they did not recognize agroforestry as a form of SWC measure. Farmers perceived that SWC measures could successfully increase crop yields and soil‐water retention, and increase land value. In general, farmers did not perceive that SWC measures successfully prevented erosion phenomena, given the evidence of on‐site erosion indicators. They attributed the continued erosion to high rainfall, steep slopes, lack of maintenance and poorly designed SWC measures. They did not consider poor soil‐cover, up‐down tillage and tall trees to be the causes of erosion. Farmers faced several constraints in adopting SWC measures: lack of labour, tools, capital and know‐how to construct the measures. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

18.
随着经济的发展和开发建设,海南有限的耕地资源在不断减少。海南省耕地储备资源数据库的建立,能妥善解决重点项目建设占用耕地历史的遗留问题,确保海南省实现耕地总量动态平衡和耕地占补平衡,推动海南省耕地资源储备与土地开发整理产业化。本文主要介绍了采用B/S结构的海南省耕地资源储备数据库管理系统的设计与实现过程。该系统以Asp.net和SQL Server 2000数据库技术为开发工具,实现了海南省耕地资源储备管理的系统化、网络化、规范化和自动化。  相似文献   

19.
不同自然植被管理措施对红壤丘陵果园水土流失的影响   总被引:6,自引:2,他引:6  
丘陵是“山—丘—谷”的过渡地带,生态系统脆弱,一旦植被遭破坏,极易水土流失。在红壤丘陵园地应用除草剂调控水土流失试验结果表明:与传统的清耕法相比,克无踪、草甘膦、草草克、克克草和生草法可使地表径流量分别减少47.7%,20.8%,31.4%,41.3%和45.5%;可使土壤侵蚀量分别减少52.4%,39.0%,48.1%,50.7%和55.2%;可使土壤养分分别减少50.2%,37.0%,41.8%,45.8%和60.3%。除草剂对杂草再生率影响,与生草法比较,克无踪可达67.2%,草甘膦达30.3%,草草克36.8%,克克草51.2%和清耕法55.1%;克无踪调控杂草效果分别是草甘膦的2.2倍,清耕法的1.2倍。克无踪调控杂草效果显著,有望成为红壤丘陵园地培肥与水保相得益彰的有效措施。  相似文献   

20.
李凯      侯鹰    付奇    辛儒鸿  邱明昆  黄尤优    刘宝印 《水土保持研究》2023,30(3):430-439
[目的]“三生空间”时空变化及其对生态系统服务影响的研究可以揭示人地关系及其变化规律,为区域国土空间管控提供理论依据。[方法]本研究以典型都市圈——济南都市圈为例,分析了2000—2018年“三生空间”变化趋势,刻画了三生空间协同变化类型与特征,并评价了济南都市圈生态系统服务价值及其变化,最终揭示了“三生空间”变化对区域生态系统服务的影响。[结果]总体变化特征上,生活生产空间是唯一面积增长的“三生空间”类型,且其面积相对变化速度在各类型中最快,对应动态度为2.4%;400 245.31 hm2的生产生态空间转入生活生产空间,是生活生产空间扩张的主要来源;“三生空间”协同变化可划分为5种特征明显、空间上互不重叠的类型,包括生态—生活协同变化型,生产—生活协同变化型,生态变化主导型,三生稳定型,生活变化主导型;在各协同变化类型中,生活变化主导型区县的生态系统服务价值下降最为剧烈[-3 015.89元/(hm2·a)];在各转换类型中,生产生态空间向生活生产空间的转换对区域生态系统服务价值的不利影响最明显。[结论]研究提出了“三生空间”协同变化类型...  相似文献   

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