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1.
The present study illustrates a framework to analyze changes in climate aridity and soil degradation on a country scale in Italy. The spatial distribution of an indicator of soil vulnerability to degradation (the SQI, soil quality index) was compared with an aridity index (the ratio of annual rainfall to annual reference evapotranspiration) estimated on a decadal basis during 1951–2010. The aridity index decreased by 0.38% per year indicating increased aridity and a non-uniform spatial distribution of soil vulnerability to degradation. Changes in the aridity index were found associated with the lowest SQI classes, suggesting that the largest increase in climate aridity affects land with high-quality soils. Territorial disparities in the aridity index between high-quality and low-quality soils decreased over time indicating a more homogeneous and dry climate regime prevailing in the more recent decades. Results may inform sustainable land management policies and National Action Plans to combat desertification in the Mediterranean region. Areas classified at increased aridity and high vulnerability to soil degradation should be identified as a key target for climate change mitigation policies. Sustainable land management strategies are required to address the dependency between climate variations, land-use changes and soil degradation processes.  相似文献   

2.
周健  肖荣波  孙翔 《应用生态学报》2013,24(7):1977-1984
快速城市化和城市扩张引发了住区形态的变迁,但形态变迁与居民通勤能源消费关系还不明确,如何通过城市的可持续公共管理政策来控制城市住区形态变迁过程下通勤能源消费及其温室气体排放有着重要意义.以厦门为例,通过土地利用与交通耦合模型TRANUS的情景分析研究了住区形态的变迁对人口、工作以及土地消费空间分布的影响,进而分析了不同情景下通勤能源消费和温室气体排放的水平.结果表明: 基准情景下交通出行早高峰能源消费总量为54.35 tce,CO2排放为119.12 t;住区形态变迁情景下,通勤能耗和CO2排放同比基准情景均增加12%;通过适当的土地利用、交通和经济政策的实施,通勤能源消费与CO2排放同比基准情景减少7%,说明城市公共政策能够有效地控制住区形态变迁背景下通勤能源消费和温室气体排放的增长.  相似文献   

3.
Successful land restoration in impoverished rural environments may require adoption of new resource management strategies; however, feedbacks between local knowledge and introduced restoration technologies have rarely been articulated. We used interview scenarios to analyze the role of local knowledge in land restoration at a large‐scale, long‐term watershed rehabilitation and wet meadow restoration program in the highland Andes. Indigenous communities built over 30,000 check dams, terraces and infiltration ditches, and the density of erosion control structures and visible restoration varied greatly across participant communities. We developed a survey reaching across the highest restoration management intensity, lowest restoration management intensity, and non‐project (control) communities. We interviewed 49 respondents using 14 scenarios based on photos depicting biophysical phenomena related to land degradation and restoration. The scenarios generated 5,828 statements that were coded into 964 distinct concepts. As expected, respondents that built more erosion control structures had more detailed knowledge of check dam construction and ecosystem development following physical interventions. More significantly, there was a shift in the conceptualization of and attitudes toward land degradation and restoration. Respondents who built more erosion control structures were more likely to: attribute wetland hydrology to groundwater recharge rather than myth constructs about seeps and springs; attribute land degradation to human rather than mythological causes; and have more proactive attitudes regarding land restoration. Evidence suggests that when addressing severe land degradation or restoring ecosystem processes not readily observable by indigenous people, such as groundwater flow and wetland recharge, restoration success will depend on combining local and scientific knowledge.  相似文献   

4.
As the national center for politics and culture, Beijing’s urbanization level is very high. Many policies within the proposed Beijing–Tianjin–Hebei region coordinated development plan affect the expansion of urban land. Therefore, it is very important to predict urban land use changes in Beijing for planning and management purposes. In this paper, we integrated of MAS (multi-agent system) and CA (cellular automata) to simulate new satellite towns construction and ecological sensitivity impact on land use change. Physical and social driving factors were used in the combined model. The MAS involved the actions of three types of agent: regional authorities, property developers, and residents. The study used the CA model to simulate the neighborhood effects of urban land use, and the MAS model to simulate agents’ decisions. The new satellite towns and an ecological sensitivity analysis were embedded in the model to simulate the impact of decision making by the Beijing government on urban land expansion. Based on the land use data of 2005, the urban land area in 2010, 2015, 2020, and 2025 was predicted using the CA-MAS model. Urban expansion occurred faster during 2015–2025 than during the previous 10 years. Three land use types, i.e., cropland, woodland, and rural residential land, were the major sources of urban expansion. With respect to government decision making, the satellite towns were the priority areas of urban development, and urban development was restricted in ecologically sensitive areas. The New Districts of Urban Development were projected to become the main areas of future urban expansion in Beijing. The area designated for urban expansion around the ecologically sensitive areas was small. The results demonstrate that satellite towns and ecological sensitivity have large impacts on urban expansion. The results of this study will help to protect ecologically sensitive land, while enabling harmonious expansion of the city.  相似文献   

5.
姚雪玲  李龙  王锋  刘书润  吴波  郭秀江 《生态学报》2020,40(5):1663-1671
浑善达克沙地榆树疏林是分布于草原地带的隐域植被类型,相较周边的典型草原区,其植被更加茂密,乔灌丛生,水草丰美,千百年来一直是牧民的优质冬季牧场。近半个世纪以来,因人类的过度开垦以及不合理的放牧管理,浑善达克沙地植被遭到空前的破坏,沙丘活化,载畜能力降低,生态价值和经济价值严重受损。近年来,随着国家草畜平衡以及禁牧政策的推广落实,放牧的牲畜总量得到一定程度的遏制,然而大面积草场还在继续退化。在牧民对生产生活的基本需求下,牲畜总量不可能无限制的压制。另外,适度的放牧对草原生态系统健康是有益的。因此,如何改良放牧方式,合理利用草场,在保持生态良好的基础上合理发挥草场的畜牧价值,是我们亟待探索的问题。以浑善达克沙地的典型天然植被榆树疏林为例,对不同放牧方式下的植被进行调查,基于沙地特殊的基质和植被特征,探讨适合沙地的放牧利用方式。研究表明,在相似的放牧强度下,把沙地作为冬营地,其榆树种群更新正常,植被覆盖度以及植物种类等均能保持良好,而把沙地作为夏季营地,榆树疏林植被退化严重,具体表现为:(1)榆树种群自然更新受阻;(2)灌木群落大量死亡或消失;(3)草本覆盖度显著降低,植物种类减少,多年生草本比例减少,一、二年生草本比例增加;(4)裸沙面积增加,沙丘趋于活化。本研究认为目前沙地植被的退化主要由不合理的放牧引起,并非气候因素所致。沙地适合于冬季放牧而不适合其他季节放牧。借鉴牧民的传统放牧方式,建议配合周边的典型草原区实行季节性倒场放牧,仅将沙地作为冬季营地使用,既能有效保护沙地植被又能充分发挥其畜牧价值。  相似文献   

6.
By marshaling empirical data from five Machiguenga communities studied over 20 years, this paper disputes two common assumptions about the behavior of indigenous peoples in the face of increasing commercialization. First, many Amazonian researchers suggest that the social and ecological deterioration confronting native populations results from externally-imposed political, legal and market structures that compel local groups to pursue short-term, unstable economic strategies. Second, these structural explanations are combined with the increasing recognition that indigenous peoples possess a substantial agroecological knowledge to suggest that, if indigenous people receive control of adequate land and resources, they will implement their traditional knowledge in conservative resource management practices. In contrast to these assumptions, this analysis shows that the Machiguenga are not compelled by external forces (such as land tenure, migration policies or economic trends), but instead are active enthusiastic participants seeking to engage the market in order to acquire western goods. Further, despite highly adaptive traditional subsistence patterns and a vast agroecological knowledge, households and communities facing increasing degrees of market integration are progressively altering their traditional cropping strategies, planting practices, labor allocation and land use patterns toward a greater emphasis on commodity crop production and domesticated animal breeding. This increasing concentration on income generating activities subverts the environmentally-friendly nature of traditional productive practices and creates a socially, economically, and ecologically unsustainable system.  相似文献   

7.
The results of scientific research have played a central role in convincing decision-makers of the plight of farmland birds and in the development of land management measures and policies designed to reverse the population declines. Several types of study have contributed to what is now a considerable knowledge base on the ecological requirements of key species, the reasons for their declines and the remedial measures necessary to bring about population recovery. They include: monitoring; analyses of large-scale datasets; detailed studies of particular species, land-uses or land management practices; and the development and testing of solutions. As a consequence, there is now an excellent qualitative understanding of farmland bird ecology, which is well reflected in the suite of land management schemes and other policy initiatives that currently operate in England. Future research efforts should focus on the further development and testing of solutions and gaining a better understanding of the quantitative relationship between the provision of resources (especially nesting and foraging habitats) and the population response of target bird species. Such work should ensure that land management measures are deployed at the required scale, in appropriate locations and are of sufficient quality to influence the national populations of the declining species.  相似文献   

8.
中国土地利用空间格局动态变化模拟——以规划情景为例   总被引:5,自引:0,他引:5  
孙晓芳  岳天祥  范泽孟 《生态学报》2012,32(20):6440-6451
土地利用变化研究在环境可持续发展研究领域中具有重要的地位,其空间分布格局的变化影响到生物地球化学循环、气候变化、生物多样性等。采用土地利用动态变化模型Dyna-CLUE模拟了在规划情景下中国土地利用变化未来空间分布格局。将土地利用类型分为六大类,即耕地、草地、林地、建设用地、水域和其它用地。驱动因子包括地形地貌、气候、社会交通等方面,对动态驱动因子如气温、降水、人口交通等,考虑了其在未来情景下的发展趋势。基于土地利用类型与驱动因子之间的定量关系和土地利用类型之间的转换规则等,模拟出至2020年中国土地利用分布格局。结果表明,至2020年,中国东南部、黄淮海平原、四川盆地等地区耕地面积将增加,东北、西北等农牧交错区、农林交错区和沙漠边缘耕地面积将会呈轻度减少趋势;林地面积将增加1417.91万hm2,主要发生在中国东北部以及西南部水热条件好的地区;中国草地在面积上保持稳定,空间上中东部、东南地区草地面积减少,内蒙古中部,青海东部,四川盆地北缘区和青藏高原等地面积增加;建设用地增加531.76万hm2,主要发生在中国的东部地区。  相似文献   

9.
袁贞贞  王秋红  王勇  李维杰  高洁  程先  朱大运 《生态学报》2023,43(20):8279-8291
模拟多情景下区域土地利用变化引起生态系统健康状况改变,对优化用地格局和保障区域生态安全具有重要意义。基于重庆市2000-2020年土地利用和生态系统健康动态演变特征,运用生态系统健康模型和斑块生成土地利用模拟(PLUS)模型模拟自然发展(ND)、生态保护(EP)和城镇发展(UD)三种情景下土地利用变化对生态系统健康的影响程度。结果表明:(1)2000-2020年建设用地扩张迅速,耕地面积减少最多,主要向林地和建设用地转移;生态系统健康状况整体呈现向好趋势,但区域差异显著。(2)2030年土地利用类型仍以耕地、林地为主,ND、EP和UD情景的建设用地规模较2020年分别增加63.59%、44.54%和100.13%,中心城区成为建设用地扩张集聚地。(3)2030年ND和UD情景的生态系统健康值较2020年均减小,建设用地增加和林地减少成为其健康退化的重要原因;而EP情景的健康值呈上升趋势,与反映生态系统健康对土地利用变化响应弹性结果相反,可见EP情景下的土地利用优化是实现区域生态系统健康可持续发展的有效途径。研究结果可为研究区生态系统保护管理与土地利用政策优化提供参考依据。  相似文献   

10.
普氏原羚(Procapra przewalskii)是我国的特有种,青海湖地区是其唯一的分布区,青海湖国家级自然保护区对普氏原羚的有效保护、社区发展与保护之间矛盾的协调,对于生物多样性保护具有重要意义。了解青海湖国家级自然保护区周边社区对普氏原羚的保护态度、意愿及其影响因素,可以为自然保护区开展生物多样性保护工作,维持当地生态和平发展提供保障。基于问卷调查法对自然保护区周边社区的牧民和居民进行了调查,研究表明:(1)受访者认为草场质量退化(n=92,65.25%)和草场围栏设置(n=80,56.74%)是威胁普氏原羚的主要因素;在以保护普氏原羚和给予生态补偿为前提下,牧民拆除围栏的意愿有所提高(由20.78%分别提高至34.21%和40.79%);(2)管理部门的宣教活动(79.43%)、手机(31.91%)和电视(28.37%)等媒体报道是受访者了解野生动物保护相关政策法规的主要渠道,可以增进受访者对政策法规的了解,积极影响受访者对普氏原羚的认知(P < 0.01)、保护态度(P < 0.01)和保护意愿(P < 0.01);(3)受访者一致认为自然保护区的严格管理与保护(牧民94.81%,居民96.87%)、当地牧民对普氏原羚的包容与保护(牧民97.40%,居民87.50%)是普氏原羚能够在自然保护区周边生存的主要原因;(4)受访者对普氏原羚的保护态度和意愿均较高,且愿意参与宣传教育(92.91%)和社区共管(87.94%)工作;(5)除了受访者的文化程度、年龄、宗教信仰和家庭年收入的影响,对政策法规的了解及拆除围栏认同度是影响受访者对普氏原羚保护态度和意愿的关键因素(P < 0.01)。因此,建议自然保护区以国家公园建设为契机,加强协调保护与发展的科学研究,深入开展宣传教育,增进社区对自然保护区生物多样性的认识,提升社区共管参与度。  相似文献   

11.
In a recent study by our group on the prevalence of intestinal parasitic infections and on the knowledge, attitudes and practices of local residents of Campos dos Goytacazes, Rio de Janeiro, Brazil, we observed that about 50% of the inhabitants were parasitized and had some knowledge of intestinal parasitic infections but did not apply this knowledge in daily practice. We were thus motivated to implement strategies in health education to promote preventive measures in the locality. The goal of the present work was to evaluate the influence of health education on the prevalence of intestinal parasitic infections in the region in an effort to strengthen public policies for controlling these diseases in Brazil. The methodology adopted was based on action-research and a theoretical framework of health promotion. Our results demonstrate that the study population exhibited an enhanced awareness of the importance of disease from intestinal parasitic infections. Attitudes and practices related to prevention were significantly improved after the shared health education. In conclusion, this study allowed the shared construction of knowledge that reflected the true needs of the residents.  相似文献   

12.
Land development is necessary for human progress, but its impact has resulted in the degradation of ecosystem services not only locally and regionally, but globally as well. Human behavior toward land use/land-use change (LULUC) must be examined and fully understood in order to achieve better land management. Several studies were recently conducted on LULUC patterns, suggesting a relationship between spatial distribution of LULUC and land attributes. We reviewed these studies and listed the factors determining spatial distribution of LULUC, and then we categorized them into: (1) socioeconomic factors, subcategorized into accessibility, local community development, spatial configuration, and political restrictions; and (2) natural environmental factors, subcategorized into topography and productivity. Here, we discuss the effects of these factors, especially road construction as a socioeconomic, accessibility factor, and slope as a natural environmental, topography factor. We also discuss the future work required to provide the tools for better land management.  相似文献   

13.
长江源区土地覆盖变化与草地退化格局的时空分异   总被引:1,自引:0,他引:1  
基于野外调查、遥感影像和统计资料,分析了1987-2007年长江源头地区土地覆盖变化和草地退化格局的时空分异特点,并从海拔、坡度和坡向3方面探讨了导致长江源区草地生态环境变化的主要自然因素.结果表明: 研究期间,长江源头地区土地类型破碎化整体呈增加趋势,自然地理条件和气候变化是导致土地格局变化的主要驱动因素;不同海拔草地退化面积差异显著,研究区草地退化主要发生在海拔4800~5100 m范围内,且退化面积随海拔的升高呈增加趋势,退化面积比重在不同坡度和坡向的差异较大.1987-2007年,长江源头地区气候呈暖干化趋势,区域土地覆盖类型空间结构变化明显;不同坡向、坡度和海拔的草地退化分布格局与高寒环境和人为干扰的格局基本一致,高寒环境和气候演化对草地生态系统格局起决定作用.  相似文献   

14.
Spatially expanding economies threaten the status of basic natural resources. In particular, wildlife habitats rarely benefit. Apart from protected areas, political-economic decision-making is ill-prepared to accommodate wildlife habitats with standard valuation methods. In some cases habitat loss is an inadvertent outcome of resource conservation policies intended to lower resource consumption.We recognize the term resource conservation as multifaceted, with a range of meanings from protecting wildlife habitats to efficiently allocating and using materials and energy. Resource conservation policies that spur economic benefits may produce unwanted outcomes. This is partly because linkages between economic and conservation goals seem tangential. Moreover, relevant information is imperfect and predictive tools are limited. This is particularly true for land converting impacts, which are often addressed after the fact, not during policy formulation, and can lead to successive resource degradation.We argue for the need to calculate the positive and negative land converting impacts from resource conservation policies that may expand the economy. Using the Ecological Footprint (EF) approach, we tested for potentially perverse outcomes of an existing resource conservation policy. In doing so, we conceptually mapped linkages among economic sectors to their cumulative effects of converting land. We assume an inverse relationship between economic expansion and land conservation.A New York State energy efficiency incentive program was tested using recent data from all tracked economic sectors. The economic data were converted in a series of steps from dollar values to energy units, to carbon dioxide emissions, and ultimately expressed in hectares of net land conversion. A policy scenario was compared to a reference scenario (no resource conservation policy), and the results anticipate a net gain in conserving land (0.6% reduced conversion). We interpret this as a potentially proportional offset favoring wildlife habitat retention. Two sensitivity analyses demonstrated that the policy’s impact on conserving land depended on both the affected economy’s scale (tripling reduces the estimated benefit to 0.2%), and the level of economic expansion that followed (doubling leads to a net loss of wildlands).This novel use of the EF approach may serve as a model for a more general approach to assessing a broader class of policies. It may also hold promise toward developing tools that can better examine well-intentioned resource conservation policies with uncertain outcomes. Our hope is that work like this can lead to better sets of tools for examining critical ecological–economic linkages for improved policy design.  相似文献   

15.
Sustainable resource management intends to allocate resources in such a way that unnecessary deterioration of biophysical and socio-economical systems is avoided. In Bukoba Area where rainfalls are plenty, evergreen grasslands were expansive and forests were limited, eucalypts ( eucalyptus spp.) and pines ( pinus spp.) were grown on grasslands for preventing land degradation through deforestation and for providing additional source of income for rural poor. This study shows that in addition to detrimental consequence of eucalyptus and pine forests on soil resources, conversion of Bukoban grasslands to forests has negatively impacted livelihood of the rural poor. Growing eucalypts and pines on grasslands prevented a farming system that enabled integration of grasslands, cattle keeping and crop production. Consequently, the grasslands role of nutrients cycling was disrupted, food crop production reduced, home-gardens productivity declined, majority deprived important livelihood asset and foreign income flow into the area reduced.  相似文献   

16.
This study assesses land-use conflicts in the Okavango wetland ecosystem. A survey of the livelihood activities of a sample of four villages has been carried out and a stakeholder approach used to identify and analyse the key actors involved in resource competition and conflicts in the area. Traditional and emerging stakeholders were identified and found to be in conflict not only with each other but within themselves. Institutional policies on land use in the area are not properly harmonized, and there has been a top-down approach to development planning and implementation of development programmes. As a result, land-use conflicts have escalated in the area. The Okavango Delta Management Plan adopted in 2007 should integrate and harmonize all the land-use policies, and land management in the area.  相似文献   

17.
基于RS与GIS的海南西部土地沙化/土地退化动态趋势研究   总被引:10,自引:0,他引:10  
遥感和地理信息系统技术的发展为研究沙化/土地退化动态趋势变化提供了有效手段,以1987年和1998年的TM遥感资料为信息源,综合GIS参与监督分类及目视读的方法,以GIS为工具提取土地沙化/土地退化动态信息。结果表明海南省西部研究区土地沙化面积在减少,严重沙化区已基本得到整治,但由于对部分地区生态环境的保护不力,使得这些地区继续沙化同;同时,该研究区土地 化区明显的向着逆转的方向发展,但季雨林面积  相似文献   

18.
Human livelihood needs and nature conservation often contradict. Yet, healthy ecosystems are crucial for human livelihood quality. The semi-arid regions of East Africa suffer under demographic pressure and soil depletion. Ecosystem degradation becomes particularly visible along rivers in semiarid regions of south-east Kenya, where former pristine riparian forests have been transformed into agricultural fields and settlements with negative effects on ecosystem services. In this study, we aim to understand how local smallholders perceive the challenges for the riparian ecosystems and what factors affect their engagement in environmental conservation. We surveyed about 200 farmers and performed expert interviews with representatives from governmental institutions from the field of land- and resource management along Nzeeu River in south-east Kenya. We assessed the level of education, land use practices, environmental knowledge, attitudes and the willingness to contribute to nature conservation. We tested for spatial bias to understand smallholders’ perceptions on environmental challenges. Our data show that land division due to inheritance is not perceived as a problem by the farmers. However, owners holding?<?1 ha of land property are less willing to spare some of their land for conservation, as opposed to those holding land plots above this size. Despite a high level of general willingness to conserve ecosystems, our data underline that local people hardly actively engage in conservation action. Furthermore, our data indicate a communication gap between local smallholders and regional governmental officers as well as overconfidence in mass media through the radio which can contradict successful adoption of pro-environment behavior. Sustainable land management in our study area is not a matter of education, but depends from the size of land property. There is an urgent need to bridge this communication gap, as a prerequisite to improve sustainable land management.  相似文献   

19.
In this paper, we present a method to estimate the additional costs made by nature reserve managers to mitigate the effects of atmospheric deposition. Theoretically, these extra costs may be saved when deposition levels drop. The costs were calculated per Nature Target Type (NTT) and management intensity for both the current (high) and reduced deposition levels. The resulting ecological quality was estimated in both cases. We calculated the difference in costs based on the management intensities required to maintain ecological quality at the current and reduced nitrogen deposition levels. For the NTTs within the clusters grassland, reed and rough land, and heathland we used dynamic simulation models. For forests and moorland pools we used expert knowledge to estimate the reduction in management costs due to a decrease in deposition. The total amount of money that may be saved because of the reduction of deposition rates is estimated at 42 million euro per year for the period from 2000 to 2020 for the assessed NTTs. The highest savings can be made in grasslands; 28 million euro. On average the savings were 80 €/ha/yr, which ranged from 5 €/ha/yr for forest to 299 €/ha/yr for reed and rough land.  相似文献   

20.
In Iran, mangroves are located in the south of the country, where they fulfill essential ecosystem functions, but some parts of them have been destroyed for various reasons in recent years so that it seems necessary to have a management plan consistent with the conservation of this ecosystem. But, it needs knowledge of the trend of and reasons for the degradation of these forests. So, the primary idea of this research was to discover the factors involved in the degradation of these forests and how to manage them. So, the research first used the remote sensing technique to determine the rate of their degradation over the last 20 years. Then, using the Delphi technique, 45 factors were identified for the degradation of these forests and they were classified into five categories including climatic and environmental, anthropogenic, socioeconomic, psychological, and policymaking and legal. Finally, the analytic hierarchy process (AHP) was used to rank these factors within two management paradigms of remediability and preventability so that the ecosystem can be soundly managed by classifying these factors. Overall, the results can provide policymakers with new insights into forest management and the policies presented here can contribute to the sustainability of this ecosystem.  相似文献   

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