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991.
??The proper management of solid waste (SW) is a global environmental challenge. A major issue is the proper disposal of SW while balancing a wide range of criteria and working with different spatial data. In this study, we used geographic information system as a tool to perform multi-criteria decision analysis with an analytical hierarchy process to develop an environmental impact susceptibility model (EISM) for landfills. The model was applied to the state of California, USA and results are presented herein. In particular, the EISM considers factors such as geology, pedology, geomorphology, water resources, and climate as represented by 13 associated environmental indicators. The results of the EISM indicate that more than 75% of California’s territory is situated in areas with very low, low, and medium environmental impact susceptibility categories. However, in the remaining 25% of the state’s land, 61 landfills are located in the high and very high categories. These results are alarming because during the period from 2000 to 2015, these 61 landfills received approximately 308 million tons of SW, which corresponds to more than 57% of all SW disposed in California. The model results can be used toward mitigating the environmental impacts of these facilities.  相似文献   
992.
It is often assumed that places of cultural significance to Aboriginal and Torres Strait Islander peoples are protected under cultural heritage legislation such as the Aboriginal Cultural Heritage Act 2003 in Queensland. Such Acts are improvements on previous policies, which all but neglected Aboriginal cultural heritage. Nevertheless, the aims of policies developed at wider geographic scales, such as States within the Australian system, continue to be disconnected from the experiences of some local Traditional Owners. In this paper, we examine conflicts between non-local policy and on-ground management decisions for Aboriginal cultural heritage in peri-urban Queensland. We focus on the challenges of local Traditional Owners in peri-urban landscapes, basing our discussion on recent experiences conducting research on Indigenous land management in southeast Queensland. We examine three case studies: one in which colonial heritage values were prioritised over existing Aboriginal cultural heritage values, a second where local government failed to support a private landholder’s attempt to identify and protect a cultural heritage site, and a third where a cultural heritage site was protected but in a way that restricts the continuation of cultural practices. Developing more productive and equitable relationships between Traditional Owners and non-Indigenous decision makers, with regards to Aboriginal cultural heritage, requires new locally developed processes for engagement and we suggest how this could be achieved.  相似文献   
993.
A wide-ranging set of physical, urban, demographic, socioeconomic, and policy characteristics determines the spatial distribution of urban forests. Information on the characteristics surrounding tree removals on both public and private properties has received less attention in the literature. The purpose of this research was to analyze the spatiotemporal trends and geographic patterns of tree removals in Austin, Texas, between 2002 and 2011 in an effort to understand how site-specific characteristics influence urban tree removal and affect the overall distribution of Austin's urban forest. We examined permitted tree removals using a geographic information system (GIS) as well as spatial and statistical analyses. Specifically, we evaluated the degree to which variables related to various physical, urban, and socioeconomic conditions predicted tree removals. The results indicate that permitted tree removals and their associated characteristics in Austin have varied over the ten-year study period. Permitted tree removals increased over the study period and took place in the urban core and along the urban periphery. Permitted tree removals were more likely to be undertaken by college graduates and owner-occupants and to occur in more densely populated areas, closer to major streets, and on properties with older structures. The results of this research provide urban forest professionals with information on the location and intensity of permitted tree removals and the significant characteristics driving urban tree loss.  相似文献   
994.
Crop diversity (e.g. the number of agricultural crop types and the level of evenness in area distribution) in the agricultural systems of arid Central Asia has recently been increased mainly to achieve food security of the rural population, however, not throughout the irrigation system. Site-specific factors that promote or hamper crop diversification after the dissolvent of the Soviet Union have hardly been assessed yet. While tapping the potential of remote sensing, the objective was to map and explain spatial patterns of current crop diversity by the example of the irrigated agricultural landscapes of the Fergana Valley, Uzbekistan. Multi-temporal Landsat and RapidEye satellite data formed the basis for creating annual and multi-annual crop maps for 2010–2012 while using supervised classifications. Applying the Simpson index of diversity (SID) to circular buffers with radii of 1.5 and 5 km elucidated the spatial distribution of crop diversity at both the local and landscape spatial scales. A variable importance analysis, rooted in the conditional forest algorithm, investigated potential environmental and socio-economic drivers of the spatial patterns of crop diversity. Overall accuracy of the annual crop maps ranged from 0.84 to 0.86 whilst the SID varied between 0.1 and 0.85. The findings confirmed the existence of areas under monocultures as well as of crop diverse patches. Higher crop diversity occurred in the more distal parts of the irrigation system and sparsely settled areas, especially due to orchards. In contrast, in water-secure and densely settled areas, cotton-wheat rotations dominated due to the state interventions in crop cultivation. Distances to irrigation infrastructure, settlements and the road network influenced crop diversity the most. Spatial explicit information on crop diversity per se has the potential to support policymaking and spatial planning towards crop diversification. Driver analysis as exemplified at the study region in Uzbekistan can help reaching the declared policy to increase crop diversity throughout the country and even beyond.  相似文献   
995.
Outdoor domestic water use is often targeted by demand management strategies. However, despite a rich empirical evidence base coming from primary studies, it is still unclear how factors that influence this type of demand interact and which are the most suitable to be addressed by water conservation programs. Based on 423 scientific contributions, we develop a research synthesis combining a variety of techniques to create a theoretical model of the relationships among factors most consistently observed in the literature. The findings uncover a great degree of complexity in terms of interactions between spatial-structural, social-structural, and cultural and psychological factors at different scales. For researchers, the methodology and the outcomes can be useful to better frame existing and future research within the literature on the topic. In practice, the adaptation of the theoretical model to local specificities can facilitate the design of more efficient and integrated demand management strategies.  相似文献   
996.
In this paper, we present a reflexive examination of how and why we, an academic and a practitioner, arrive at different evaluations of collaborative progress in natural resource management. We situate this examination in our long-standing involvement in designing, adaptively managing, and participating in the Uncompahgre Plateau collaborative forest restoration project in western Colorado, USA. Drawing on the concept of “positionality” in qualitative social science research, we disclose our respective motivations, assumptions, roles, and power relative to the collaborative process. The differences in evaluating collaborative progress stem from our respective professional positionality. For the academic, the guiding interest was to test theory and promote success for his applied research institute; for the practitioner, the motivation was to build trust to allow her field staff the flexibility to implement management actions and demonstrate effectiveness as an agency line officer. These epistemological differences draw attention to the importance of transdisciplinary approaches to producing knowledge from shared practice, starting with efforts to explicitly disclose and honor differing interests, assumptions, and frames of reference stemming from each party’s personal and professional biographies and institutional norms. This reflexivity is essential to advancing knowledge about collaboration in natural resource management.  相似文献   
997.
This study applies an integrated moral obligation model to examine the role of environmental and cultural values, and beliefs in the activation of landowner conservation norms. Data for this study were collected through a self-administered survey of riparian landowners in two Minnesota watersheds: Sand Creek and Vermillion River watersheds. Study findings suggest that collectivistic and biospheric–altruistic values form the bases for the activation of personal norms. Further, beliefs about local responsibility and ability to act influence personal norms to protect water resources. Findings suggest that landowners’ personal norms of water conservation are more likely to be activated by conservation strategies that appeal to biospheric–altruistic and collectivistic values, emphasize adverse consequences of water pollution, highlight water resource protection as a local responsibility, and provide the resources needed to protect water resources.  相似文献   
998.
作为关键生态保护区域边界线,生态红线划定当前已经上升为中国国家层面战略部署,然而当前生态红线的研究尚处于探索阶段,对于如何针对红线区域具体设计法规保障、制定管理规则、限定开发行为等方面的研究较为匮乏。鉴于英国已经较为成熟的科研专用区相关保护管理的历史经验,梳理和定位了英国科研专用区的3个发展阶段,探讨了各个发展阶段的基本原则、管理机制和实施保障的演变过程,总结英国科研专用区的规划与管理经验,提出了完善法律保障与规程规范、实施统一监管和区域统筹、并行生态补偿与保护自住、签订标准化管理协议、加强公众参与与研讨机制、提升资金保障与使用效率等对我国生态红线区管理与保障的有益借鉴。  相似文献   
999.
A large proportion of the rural labor force in China will continue to transfer to non-agricultural sectors in the near future, which will inevitably lead to the transformation of the agricultural production mode and the structure of the farmers’ livelihood. The Chinese government is making great efforts to govern agricultural nonpoint source pollution (ANSP), and farmers' environmental behavior is a key factor that must be considered in the formulation of agricultural environmental policies. Based on a set of micro survey data on farmers in the study area and econometric methods, this study investigates the impact of agricultural labor transfer on ANSP by considering the substitution effect of agricultural factors and the effect of agricultural economies of scale. The results show that the increase of the agricultural labor force will not be conducive to reducing ANSP, while the income increase brought by agricultural labor transfer will improve the input structure of agricultural factors and have a positive impact on ANSP reduction. Government departments should provide subsidies or incentive measures to help agricultural social service organizations to expand their coverage and increase the frequency of socialized agricultural services, in order to guide farmers in the use of environment-friendly agricultural technology to reduce the ANSP caused by agricultural factors at the source. Furthermore, it is necessary to facilitate the development of small-sized agricultural machinery suitable for small-area land cultivation.  相似文献   
1000.
山区合适耕地经营规模确定的实证研究——以重庆市为例   总被引:1,自引:0,他引:1  
范乔希  邵景安  应寿英 《地理研究》2018,37(9):1724-1735
在地形起伏、地块破碎、分布半径较远等约束下,山区多大的经营规模是合适的?这是目前必须弄清的科学问题之一。使用480份有效调查问卷,以投入农业的劳动力为测算单位,以劳均纯收入为评价指标,分作物类型和地块分布半径,构建计量经济模型,测算不同条件下合适的耕地经营,结果表明:① 在现有社会经济条件下,样本村农业土地适度规模经营面积为24~32亩,适度规模下的劳均纯收入远高于当前农村人均纯收入,且与城镇居民的差距明显缩小。② 作物类型对适度规模影响不大,但对农民纯收入产生较大作用。经济作物和粮食作物的适度规模分别为24.33亩、24.63亩,差异不显著,但种植经济作物和粮食作物在适度规模下的劳均纯收入相差3638元,巨大的差距将促使经济作物种植面积不断扩大。③ 距离对适度规模影响较大,但对劳均纯收入影响不大。0.5 km内、0.5~1 km的适度规模分别为28.62亩、31.83亩,单位劳动力的适度规模相差3亩,这表明距离是目前从事农业生产时劳动力投入时须考虑的重要因素。但是,对应的劳均纯收入相差较小,又说明伴随耕作距离的增加,更多的投入主要依靠机械来完成,从而带动适度规模的扩大。1 km外的建模未通过检验,也进一步说明未实现规模经营、没有进行机械化耕作、离家远的土地收支严重不平衡,撂荒严重,规模化经营、机械化耕作是解决距离问题的有效途径。本文得出的土地适度规模是可行的,也验证了推进土地适度规模经营的可行性和必要性。  相似文献   
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