Modeling the Ecological Consequences of Land-Use Policies in an Urbanizing Region

Insight into future land use and effective ways to control land-use change is crucial to addressing environmental change. A variety of growth-control policies have been adopted by municipal and regional governments within the United States to try to minimize the ecological impact of continued urbanization, but it is often unclear if those policies can meet the stated ecological goals. Land-use-change models provide a way to generate predictions of future change, while exploring the impact of different land-use policies before irreversible transformations occur. In this article, an approach to modeling land-use policies that focuses on their ecological consequences is described. The policy simulation approach was used to predict future land use in the Barnegat Bay and Mullica River watersheds, in southeastern New Jersey, USA. Four commonly used policies were considered: down-zoning, cluster development, wetlands/water buffers, and open space protection. The results of the analysis suggest that none of the policies modeled were able to alter future land-use patterns, raising questions about the effectiveness of commonly adopted land-use policies. However, the policy modeling approach used in this study proved to be a useful way to determine if adoption of a given policy could improve the likelihood of meeting ecological goals.     

Land-Cover Change Trajectories in Northern Ghana

Land-cover change trajectories are an emergent property of complex human–environment systems such as the land-use system. An understanding of the factors responsible for land change trajectories is fundamental for land-use planning and the development of land-related policies. The aims of this study were to characterize and identify the spatial determinants of agricultural land-cover change trajectories in northern Ghana. Land-cover change trajectories were defined using land-cover maps prepared from Landsat Thematic Mapper dataset acquired in 1984, 1992, and 1999. Binary logistic regression was used to model the probability of observing the trajectories as a function of spatially explicit biophysical and socioeconomic independent variables. Population densities generally increased along the continuum of land-use intensity, whereas distance from market and roads generally decreased along this continuum. Apparently, roads and market serve as incentives for settlement and agricultural land use. An increase in population density is an important spatial determinant only for trajectories where the dominant change process is agricultural extensification. A major response to population growth is an increase in cultivation frequency around the main market. Agricultural intensification is highly sensitive to accessibility by roads. The increase in land-use intensity is also associated with low soil quality. These results suggest the need for policies to restore soil fertility for agricultural sustainability. The models also provide a means for identifying functional relationships for in-depth analyses of land-use change in Ghana.     

Georelational Analysis of Soil Type, Soil Salt Content, Landform, and Land Use in the Yellow River Delta, China

The Yellow River Delta, one of China’s three major river deltas, is becoming a major region for the development of agriculture and fisheries. Protecting the delicate ecology of newly formed aquatic systems as well as the evolution of soils, natural vegetation, and fauna on older upland environments in the delta is a priority in planning for the wise use of the delta’s resources for future agricultural development. In this article, we use a Geographic Information System (GIS) to analyze relationships between land-use/land-cover characteristics in the Dongying municipality, one of the most intensely developed areas of the delta, and spatial variations in soil salinity and landforms. This analysis reveals that soil salt content decreases from regionally high values in isolated depressions to relatively moderate values in embanked former back swamps, with the lowest values occurring in abandoned river courses. Comparing the present land use on this soil salinity–landform pattern shows that it is basically at odds with general concepts of land suitability for agricultural utilization of saline soils. Crop-based agriculture in the region is probably overdeveloped, whereas more appropriate agricultural development, like cattle and forest production, is underrepresented. Future development should focus on converting farmland in embanked former back swamps and abandoned river courses into grasslands and forests. Crop-based agriculture (up to 151,000 ha) could be planned at the low-salinity terrace uplands and flood plains. The article provides guidelines for decision-makers regarding agricultural land use and wetland protection in the Yellow River Delta.     

浅谈以公共交通为导向的土地利用模式

本文通过对城市土地利用和城市交通规划相互关系的分析,探讨解决城市交通问题的合理用地模式,提出了要以公共交通来引导城市土地的利用,并探讨了在我国建立公共交通导向的城市土地利用形态的策略与途径。     

Integrating fire management into land-use planning: A multiple-use management research,development, and applications program

The traditional view of fire as a destructive agent requiring immediate suppression is giving way to the view that fire can and should be used to meet land management goals. Thus,fire control is being replaced by the more general concept offire management, which is based on the need to integrate fire policy with land management objectives. The social, economic, and ecologic effects of fire must be evaluated in the selection of land management alternatives.The activities of fire management organizations—fire prevention, control, and use of fire—must respond to needs of land management. Many agencies have developed fire organizations as separate entities that set their own objectives. The many land and resource managers who have recognized the need to incorporate fire considerations into land-use planning have so far lacked the techniques to do so.As a natural process, fire has an important function in forest and range ecosystems. Fire can greatly influence the quantity and quality of resource outputs; it is a two-edged sword that can either harm or benefit our goals, depending upon the complex effects of fire and the nature of our wants.The Fire in Multiple-Use Management Research, Development, and Applications (RD&A) Program was initiated by the U.S. Department of Agriculture, Forest Service, at the Northern Forest Fire Lab in Missoula to assist land managers. This profile explains what an RD&A program is; discusses its mission, goals, and approach to the problem; and tells why the approach involves federal laboratories, universities, and private research foundations.     

FORPLAN: A FORest Planning LANguage and Simulator

A Forest Planning Language and Simulator (FORPLAN) has been developed to facilitate the use of simulation for integrating fire into the land management planning process.FORPLAN incorporates unique characteristics of previous systems, links numerous models and data bases, allows selection of variable resolution levels, and permits discrete time simulation of disturbances on plants, fuels, and animals. No previous computer experience is required of the user, sinceFORPLAN recognizes simple English words and phrases.     

Natural environmental impact assessment: A rational approach

A method is presented which combines environmental indices and estimates of inputs from various land uses to aid in environmental impact assessments. Unweighted pair/group cluster analyses are used to obtain relationships between easily observable environmental indices, such as vegetation types, soils, and geology, based on their mutual recurrence. These relationships are shown by using an ordination technique which shows the nature of complex impacts on a natural system. Results are used to develop anenvironmental effects sequence diagram based on known scientific and engineering principles and observed natural relationships. The diagram may be used in conjunction with land use data to estimate the possible magnitude of impacts on the pre-existing system which may result from such land use. Several examples are developed which quantify inputs from various land uses and which compare them with environmental inputs including point source and non-point source liquid and atmospheric emmissions, land modifications, and resource consumption. Known average values are used and a separate comparison is made in describing the vast differences between the project phases of construction versus longterm operation. A hypothetical environmental impact assessment is given for a small residential development in Chambers County, Texas, U.S. of A.     

我国21世纪城市水灾风险及减灾对策

论述从50年代至20世纪末,我国城市水灾呈上升趋势,分析城市水灾的剧化与国土规划和管理、流域规划和管理、城市规划和管理上的人为失误有直接关系,指出我国21世纪城市水灾风险甚大,并提出相应的减灾对策．     

浅谈固体废物最终处置的方法

本章针对固体废物最终处置的两大途径,即陆地处置和海洋处置,着重介绍了卫生土地填埋、安全土地填埋、海洋倾倒、远洋焚烧、深井灌注处置等方法,以及它们的场地开发和利用、场地选择、设计、建造、操作等.     

Soil landscape constraint mapping for coastal land use planning using geographic information system

The aim of the study was to delineate soil landscape constraints to various land uses for urban and regional planning in the coastal areas of New South Wales (NSW), Australia. Soil landscape units mapped at 1:100,000 or coarser were sub-divided into component facets using advanced terrain modelling techniques in a geographic information system (GIS). The output facet grids were further overlain and linked with relevant GIS layers and soil databases to derive soil landscape constraint ratings for various land use purposes such as residential development, cropping and grazing. The constraint ratings for a specific land use were calculated based on objective and rule-based assessments of soil and landscape features such as engineering hazards, intrinsic fertility, drainage and other parameters. A series of soil landscape constraint maps which portray specific land use capability have been produced for the NSW coast. The methodology developed in this study has been demonstrated to be efficient in delineating soil landscape constraints and there is over 90% agreement between the model outputs and the assessment by soil surveyors with local knowledge. The output maps show levels of unprecedented detail of soil and landscape constraint for the coast of NSW and can be readily interpreted by land use planners and land managers for sustainable land use decision making practices.