共查询到20条相似文献,搜索用时 218 毫秒
1.
选取经济发达区原锡山市作为研究区域,以1982年和2005年土壤速效钾作为研究对象,分析探讨不同时空状态下区域土地利用变化对土壤钾含量的影响,以期获得较长时空条件下土壤质量对土地利用变化的响应。20年来,通过统计分析和独立样本t检验表明,原锡山市土壤速效钾含量增加了36.9mg/kg。变异函数分析表明,土壤速效钾的变异函数理论模型呈指数型,块金方差与基台值的比值、自相关阀值发生较大变化。kriging插值分析结果表明,土壤速效钾空间分布较简单,但空间变异明显。 相似文献
2.
3.
Modeling the relationships between land use and land cover on private lands in the Upper Midwest, USA 总被引:4,自引:0,他引:4
This paper presents an approach to modeling land-cover change as a function of land-use change. We argue that, in order to model the link between socio-economic change and changes in forest cover in a region that is experiencing residential and recreational development and agricultural abandonment, land-use and land-cover change need to be represented as separate processes. Forest-cover change is represented here using two transition probabilities that were calculated from Landsat imagery and that, taken together, describe a Markov transition matrix between forest and non-forest over a 10-year period. Using a three-date land-use data set, compiled and interpreted from digitized parcel boundaries, and scanned aerial photography for 136 sites (c. 2500 ha) sampled from the Upper Midwest, USA, we test functional relationships between forest-cover transition probabilities, standardized to represent changes over a decade, and land-use conditions and changes within sample sites. Regression models indicated that about 60% of the variation in the average forest-cover transition probabilities (i.e. from forest to non-forest and vice versa) can be predicted using three variables: amount of agricultural land use in a site; amount of developed land use; and the amount of area increasing in development. In further analysis, time lags were evaluated, showing that agricultural abandonment had a relatively strong time-lag effect but development did not. We demonstrate an approach to using forest-cover transition probabilities to develop spatially-constrained simulations of forest-cover change. Because the simulations are based on transition probabilities that are indexed to a particular time and place, the simulations are improved over previous applications of Markov transition models. This modeling approach can be used to predict forest-cover changes as a result of socio-economic change, by linking to models that predict land-use change on the basis of exogenous human-induced drivers. 相似文献
4.
Rosinda Leonor Pato Alexandre O. Tavares 《Journal of Environmental Planning and Management》2016,59(4):607-627
This study analysed the importance of physical forces on land-use change, on the planning framework in a Portuguese periurban area. A temporal matrix showing the trajectories of land transformation was obtained. A multivariate redundancy analysis explored the importance of physical parameters on temporal and spatial land-use change. A content analysis on urban or municipal master plans was made framing the importance of physical parameters on the planning process. The results highlighted a consistent trajectory of profound land-use changes with distinctive trajectories, with increasingly complex patterns with a limited dependence on physical variables. The trajectories were more related to the planning framework, where political actors and planning managers seemed to be most important. A theoretical model balancing three main components – physical forces, actors, and land transformation (DFA-C model) is proposed, reflecting the informal relationships between physical parameters and actors during the planning process. 相似文献
5.
土地利用战略研究是新一轮土地利用总体规划的重要内容,但目前的土地利用战略研究多是从区域整体角度进行分析,未体现区域内部空间差异,对制定差异化土地政策的指导性不强.土地利用战略分区研究可使分区结果与土地政策调控形成互动机制,提高其指导性,从而促进区域土地合理利用与有序开发,实现区域统筹发展.对土地利用战略分区的主要研究内容与原则、指标体系选择、研究方法与思路等进行了探讨,希望对完善土地利用战略及分区研究有所裨益. 相似文献
6.
Exploring changes in Ecuadorian land use for food production and their effects on natural resources 总被引:1,自引:0,他引:1
A model is used for the dynamic and spatially explicit exploration of near future agricultural land-use changes. In a case study for Ecuador, different plausible scenarios are formulated, taking into account possible developments in national food demand until the year 2010. The protection of nature parks and restrictions due to land degradation are evaluated with respect to their possible spatial impacts on the land-use change dynamics within the country. Under the assumptions of the demand scenarios, agricultural land-use expands significantly, resulting in more use of land in existing agricultural areas and frontier-type expansion into relatively undisturbed natural areas. The patterns of change depend on the increase in demand, competition between land-use types, changes in driving factors of land use, and the area and characteristics of land that is excluded from agricultural use. The modelled land-use dynamics are related to their possible impacts on the natural resource base, specifically soil fertility. The results indicate potential negative effects of land-use changes on the soil nutrient balance and biodiversity. It is argued that spatial and temporal quantification of land-use dynamics at the landscape level can support research and policies aimed at understanding the driving factors of land-use change and the behaviour of complex agro-ecosystems under changing conditions at different scales. In this way, issues dealing with sustainable food production and the management of the natural resource base can be addressed in a more integrated and quantitative manner. 相似文献
7.
Land Management Versus Natural Factors in Land Instability: Some Examples in Northern Spain 总被引:1,自引:1,他引:0
Viola Maria Bruschi Jaime Bonachea Juan Remondo Jose Gómez-Arozamena Victoria Rivas Matteo Barbieri Stefano Capocchi Mauro Soldati Antonio Cendrero 《Environmental management》2013,52(2):398-416
The objective of this work is to test a hypothesis formulated on the basis of former results which considers that there might be a “global geomorphic change,” due to activities related to land management and not determined by climate change, which could be causing an acceleration of geomorphic processes. Possible relationships between some geomorphic processes related to land instability (landslides or sediment generation) and potential triggering factors are analyzed in study areas in northern Spain. The analysis is based on landslide inventories covering different periods, as well as the determination of sedimentation rates. Temporal landslide and sedimentation rate trends are compared with different indicators of human activities (land-use change, logging, forest fires) and with potential natural triggers (rainfall, seismicity). The possible influence of the road network in the distribution of landslides is also analyzed. Results obtained show that there is a general increase of both landslide and sedimentation rates with time that cannot be explained satisfactorily by observed rainfall trends and even less by seismicity. Land-use change appears to be by far the main factor leading to land instability, with some changes producing up to a 12-fold increase of landslide rate. A relationship between road network and the spatial distribution of landslides has also been observed. These results do confirm the existence of an acceleration of geomorphic processes in the region, and also suggest that climate-related factors play a limited role in the changes observed. 相似文献
8.
合肥市近19年来土地利用格局的时空变化分析 总被引:1,自引:0,他引:1
利用Landsat TM、ETM 、CBERS—2资源卫星数据,采用基于知识型光谱特性的增强与人机交互解译相结合的方法,提取了合肥市1987年、2000年和2006年土地利用类型的专题信息。利用GIS空间分析技术和数理统计方法,分析了合肥市近19年来的土地利用变化特征。结果表明:①在整个阶段—耕地减少了23.38%,建设用地增加了61.26%;城镇用地新增速度最快,且新增速率远大于转移速率,属高速扩张型;②区内最"敏感"的类型是交通用地,其新增速率在两个阶段分别达到1.64和1.62,远高于其它的类型;④从城市扩展的方向上看,合肥城市的发展主要以西南部、南部和东部为主,西南部最为明显;城市已经形成以老城区为核心,向东、北、西南三翼伸展,形成"南进—东拓—西缓—北抑"的空间发展布局。 相似文献
9.
10.
The institutional structure and public service delivery apparatus required to meet the future effects of climate change already exist in Norway. However, there are huge challenges in coordinating these institutions at different authority levels for climate change adaptation purposes. Based upon a broad case study, this article presents how local actors consider the multi-level coordination of different levels of government and policy sectors to function today, which are the mechanisms that are used and what are the coordination challenges that are identified. Based upon the challenges revealed, this article discusses how best can the government-level institutions be organised for better goal attainment. We argue here that the elected regional level in Norway – the counties – has a huge potential to act as a multi-level coordination actor. 相似文献
11.
Toronto is among the fastest-growing urban regions in North America. Regional efforts to preserve rural landscapes and remnant
habitat have had variable success. In the 1990s, significant conflict emerged over proposals to build large housing developments
on portions of the Oak Ridges Moraine, a 160-km stretch of environmentally sensitive land along the city’s northern edge.
After years of planning conflict, Ontario’s provincial government created the Oak Ridges Moraine Conservation Plan, an Act
of the Ontario Legislature. The Plan represents a dramatic change in Ontario’s approach to conservation planning. We examine
the development and implementation of the Conservation Plan as an example of environmental planning policy in a complex urban
setting. Data from interviews with policy actors, planning agency documents, and geospatial sources are used to construct
an analysis and discussion of the Plan and its implementation. From a policy research perspective, the evolution and implementation
of the Plan require analysis and monitoring to better understand how such approaches can best be implemented. The Conservation
Plan marks a change in policy in Ontario, and the implementation process highlights challenges in putting conservation plans
into practice. 相似文献
12.
Mark R. Stevens Philip R. Berke Yan Song 《Journal of Environmental Planning and Management》2008,51(6):737-757
Research suggests that characteristics of local government land-use planners help determine the priority that local communities place on flood hazard mitigation. However, research has not examined the significance of land-use planners' values and role orientations for flood hazard mitigation. Multiple regression analysis is used to examine the influence that land-use planners' values and role orientations have on flood hazard mitigation in a national sample of New Urbanist development projects. Findings indicate that land-use planners' values and role orientations have significant implications for flood hazard mitigation in these projects. The paper recommends that local governments adopt a land-use planning approach to flood hazard mitigation that relies on land-use planners to help direct development away from hazardous portions of development sites. 相似文献
13.
Juha Peltomaa Mikael Hildén Suvi Huttunen 《Journal of Environmental Policy & Planning》2020,22(2):268-280
ABSTRACTDuring policy change, the role of the actors communicating the change to different audiences is accentuated. The media plays an increasing role, either as an actor or by providing a stage for other actors. In particular, specialised journals represent an influential, albeit understudied, sphere of policy studies. We use the narrative policy framework complemented with frame analysis to trace how specialised media can affect policy implementation through implicit suggestions for action. Using this combined approach, we analyse how specialised forest journals, which are the most important forest information source for Finnish forest owners, have conveyed the renewal of forest legislation in Finland. The core message of the journals is that forest owners should, despite their new freedom granted by the reform, rely on experts rather than experimenting when managing their forests. This suggests that the media contributes to a path-dependent continuation of a forest policy that is based on a rationalistic exploitation ethos. The innovative potential, which the policy change aimed at encouraging, is thereby partially undermined. However, the analysis of the narratives also reveals that forest expertise and professionalism are diversifying. This notion is important as diversity can eventually lead to narratives supporting more fundamental change in forests management. 相似文献
14.
Implementing Participatory Decision Making in Forest Planning 总被引:2,自引:0,他引:2
Ananda J 《Environmental management》2007,39(4):534-544
Forest policy decisions are often a source of debate, conflict, and tension in many countries. The debate over forest land-use
decisions often hinges on disagreements about societal values related to forest resource use. Disagreements on social value
positions are fought out repeatedly at local, regional, national, and international levels at an enormous social cost. Forest
policy problems have some inherent characteristics that make them more difficult to deal with. On the one hand, forest policy
decisions involve uncertainty, long time scales, and complex natural systems and processes. On the other hand, such decisions
encompass social, political, and cultural systems that are evolving in response to forces such as globalization. Until recently,
forest policy was heavily influenced by the scientific community and various economic models of optimal resource use. However,
growing environmental awareness and acceptance of participatory democracy models in policy formulation have forced the public
authorities to introduce new participatory mechanisms to manage forest resources. Most often, the efforts to include the public
in policy formulation can be described using the lower rungs of Arnstein’s public participation typology. This paper presents
an approach that incorporates stakeholder preferences into forest land-use policy using the Analytic Hierarchy Process (AHP).
An illustrative case of regional forest-policy formulation in Australia is used to demonstrate the approach. It is contended
that applying the AHP in the policy process could considerably enhance the transparency of participatory process and public
acceptance of policy decisions. 相似文献
15.
Charles W. Welby 《Journal of the American Water Resources Association》1984,20(6):875-882
In urbanizing areas underlain by crystalline rocks an inventory of the usable ground water should form an important element in the land-use planning process. Land-use decisions are most often made upon water-well yield data alone, but these data do not address the inventory question. A method utilizing local geology, stream lowflow characteristics, and pumping test data permitted outlining portions of Wake County, North Carolina, which are more favorable and those which are less favorable for ground water supply development. Information from state-required 24-hour pumping tests on 232 wells was supplemented by information from an additional 100 wells whose initial yields were determined by shorter pumping tests. Comparison of the ground water inventory values on a per acre or per square mile basis with average water use at various residential densities provides information useful to the responsible political body as it decides about population density distribution and the need for surface water supplies. For Wake Country an average density of one residential unit per acre appears generally permissible before overdraft of the ground water supplies becomes a significant risk. By utilizing the ground water inventory and patterns of ground water yields from various rock types, county officials can maximize the effectiveness of public facilities funds. The technique appears useful for other parts of the Piedmont region of the southeastern United States. 相似文献
16.
Groundwater Vulnerability Assessment Combining the Drastic and Dyna-Clue Model in the Argentine Pampas 总被引:3,自引:0,他引:3
Vulnerability assessment is considered an effective tool in establishing monitoring networks required for controlling potential
pollution. The aim of this work is to propose a new integrated methodology to assess actual and forecasted groundwater vulnerability
by including land-use change impact on groundwater quality. Land-use changes were simulated by applying a spatial dynamics
model in a scenario of agricultural expansion. Groundwater vulnerability methodology DRASTIC-P, was modifyed by adding a land-use
parameter in order to assess groundwater vulnerability within a future scenario. This new groundwater vulnerability methodology
shows the areas where agricultural activities increase the potential level of groundwater vulnerability to pollution. The
Dulce Creek Basin was the study case proposed for the application of this methodology. The study revealed that the area with
Very High vulnerability would increase 20% by the year 2020 in the Dulce Creek Basin. This result can be explained by analyzing
the land-use map simulated by the Dyna-CLUE model for the year 2020, which shows that the areas with increments in crop and
pasture coincide with the area defined by the Very High aquifer vulnerability category in the year 2020. Through scenario
analysis, land-use change models can help to identify medium or long term critical locations in the face of environmental
change. 相似文献
17.
Eivind Junker 《Local Environment》2015,20(4):474-488
Land-use planning has been promoted as an important tool for adaptation to climate change. However, its success depends on effective communication between researchers and decision-makers. A “risk and vulnerability assessment” (RVA) is one method to facilitate the interaction between the groups. RVAs have been performed in Norwegian land-use planning for about 20 years, and been mandatory for new development the last few years. The first part of the article reviews the history and current legal regulation of RVAs in Norway. Continuing, the main part discusses the distribution of authority and responsibility for different parts of the process and result. The key finding is that significant decisions are deferred to municipal discretion, for example, the necessity (if doubtful) and scope of the assessments. Other topics (such as the burden of costs and eligible performers) are largely unregulated, prompting some arguments about the need for further legislative effort. 相似文献
18.
This article investigates the policy formulation process related to seismic hazard mitigation. A preemergent policy climate is identified by focusing on key actors, assessments of seismic risk, and policy alternatives. Two major factors were found to affect key actor support for policy development: (a) the objective risk to which their constituent community is exposed, and (b) their elective or appointive position at the local level of government. 相似文献
19.
Le Thi Hong Phuong G. Robbert Biesbroek Arjen E. J. Wals 《Journal of Environmental Policy & Planning》2018,20(4):518-532
Governments fulfil important roles in increasing the adaptive capacity of local communities to respond to climate change impacts, particularly in developing countries. Existing studies on how governments enable and constrain the ways in which local level communities learn and build their adaptive capacity, however, generally adopt network or market-oriented types of governance. However, the most vulnerable regions to climate change impact in the world are generally governed through hierarchical policy systems. This research aims to understand how the hierarchical policy system in Vietnam creates enables and/or constrains the policy capacity of policy actors to contribute to effective climate change adaptation. We conducted interviews (n?=?26) with key actors at multiple levels of government. Our findings show the importance of clear legal institutions, available financing for implementing policies, and the training of governmental staff, particularly at district and commune levels where the policy capacities are generally too low to deal with climate change impacts. We conclude that any efforts to support local actors (i.e. smallholder farmers) should include investments in policy capacity to ensure uptake and upscaling of adaptation actions more broadly. 相似文献
20.
Western European landscapes have drastically changed since the 1950s, with agricultural intensifications and the spread of
urban settlements considered the most important drivers of this land-use/land-cover change. Losses of habitat for fauna and
flora have been a direct consequence of this development. In the present study, we relate butterfly occurrence to land-use/land-cover
changes over five decades between 1951 and 2000. The study area covers the entire Swiss territory. The 10 explanatory variables
originate from agricultural statistics and censuses. Both state as well as rate was used as explanatory variables. Species
distribution data were obtained from natural history collections. We selected eight butterfly species: four species occur
on wetlands and four occur on dry grasslands. We used cluster analysis to track land-use/land-cover changes and to group communes
based on similar trajectories of change. Generalized linear models were applied to identify factors that were significantly
correlated with the persistence or disappearance of butterfly species. Results showed that decreasing agricultural areas and
densities of farms with more than 10 ha of cultivated land are significantly related with wetland species decline, and increasing
densities of livestock seem to have favored disappearance of dry grassland species. Moreover, we show that species declines
are not only dependent on land-use/land-cover states but also on the rates of change; that is, the higher the transformation rate from small to large farms, the higher the loss of dry grassland species.
We suggest that more attention should be paid to the rates of landscape change as feasible drivers of species change and derive
some management suggestions. 相似文献