Land-use suitability analysis in the United States: historical development and promising technological achievements

Various methods of spatial analysis are commonly used in land-use plans and site selection studies. A historical overview and discussion of contemporary developments of land-use suitability analysis are presented. The paper begins with an exploration into the early 20th century with the infancy of documented applications of the technique. The article then travels through the 20th century, documenting significant milestones. Concluding with present explorations of advanced technologies such as neural computing and evolutionary programming, this work is meant to serve as a foundation for literature review and a premise for the exploration of new advancements as we enter into the 21st century.     

Statistical evaluation of an agricultural land suitability model

The land evaluation and site assessment (LESA) method has been used extensively in the United States to assess agricultural land suitability for different localities. Despite widespread use, LESA models rarely have been evaluated in a systematic, comprehensive manner. This article discusses development of a LESA system for Hawaii, the first statewide application of the LESA methodology. The empirical model was implemented with a computerized geographic information system (GIS). The system's efficiency, ability to discriminate among land parcels, and robustness to subjective model parameter values are evaluated with statistical analyses and map overlays of GIS data. Results show great potential to simplify the original model specification, primarily through deletion of marginal site assessment factors. System output was generally insensitive to the numeric values selected for model parameters, with exception of the ratio used to combine the land evaluation (LE) and site assessment (SA) component scores. Relative supplies of the differing land attributes measured by the two components must be considered in determining an appropriate LE:SA ratio for a given area.     

Compromise solutions to the acid deposition control problem: a theoretical model and some simulation results

Acid deposition is a muitifaceted environmental phenomenon whose control represents one of the most controversial environmental policy areas. Because of the longrange transport of air pollutants contributing to acid deposition, its control is the responsibility of more than one region. Given the interdependence between the economic and environmental impacts of acid deposition as well as the interregional conflicts over its control, the present article proposes an interregional integrated economic-environmental model for the study of the impacts of acid deposition control policies. This model is solved with the use of a compromise programming procedure which facilitates the explicit treatment of conflicting regional goals. After the theoretical and operational forms and the solution procedure of the proposed model are described, the use of the model is illustrated with a simulation example using the 1963 MRIO accounts and hypothetical environmental data. The compromise programming procedure can form the basis for interactive decision processes when policy makers are exposed to the solutions yielded by the model. The model's usefulness and future research directions are discussed.     

Geographic information systems within the national health service: the scope for implementation

The paper starts by assessing some of the needs for information management within the health service in Great Britain. Geographic Information Systems are introduced, and some of the functions such as database management, networking and overlying are described. Principally, it is argued that GIS can fill the role as a health information system, resource management system, and has the potential to assist in family practitioner monitoring and epidemiological studies.     

Suitable Housing Placement: A GIS-Based Approach

The intent of this paper is to operationalize some aspects of local sustainability in a suitable development scenario and to compare its energy-use and environmental impacts to trend development. After a discussion of suburban sprawl, local sustainability, and the current state of the Pennypack Creek Watershed in the Philadelphia metro region, these residential location scenarios are presented. The latter were created using geographic information systems software and are based on projections from the Delaware Valley Regional Planning Commission. The impacts of the scenarios on energy use, air emissions, greenhouse gas emissions, water quality, and biological integrity were estimated with very few data, and the effect on the value of generic ecosystem services was assessed. The suitable development scenario was 29% better in terms of energy use and air and greenhouse gas emissions, 2.4% worse on water quality, and 2.6% better with respect to biological integrity. Given its net beneficial results, recommendations for policies to engender suitable development are made, and an outline of an implementation plan is proposed. Thoughts regarding refinements of the present work and the applicability of the methods used here to other watersheds conclude the work.     

Land Degradation: A Challenge to Ethiopia

Land degradation is a great threat for the future and it requires great effort and resources to ameliorate. The major causes of land degradation in Ethiopia are the rapid population increase, severe soil loss, deforestation, low vegetative cover and unbalanced crop and livestock production. Inappropriate land-use systems and land-tenure policies enhance desertification and loss of agrobiodiversity. Utilization of dung and crop residues for fuel and other uses disturbs the sustainability of land resources. The supply of inputs such as fertilizer, farm machinery and credits are very low. The balance between crop, livestock, and forest production is disturbed, and the farmer is forced to put more land into crop production. For environmentally and socially sustainable development, there is an urgent need to promote awareness and understanding of the interdependence of natural, socioeconomic, and political systems at local and national levels. Understanding the current status and causes of land degradation is very important. This paper reveals the important elements of land degradation in Ethiopia and suggests possible solutions that may help to ameliorate the situation.     

An introduction to digital methods in remote sensing of forested ecosystems: Focus on the Pacific Northwest,USA

Aerial photography has been routinely used for several decades by natural resource scientists and managers to map and monitor the condition of forested landscapes. Recently, along with the emergence of concepts in managing forests as ecosystems, has come a significant shift in emphasis from smaller to larger spatial scales and the widespread use of geographic information systems. These developments have precipitated an increasing need for vegetation information derived from other remote sensing imagery, especially digital data acquired from high-elevation aircraft and satellite platforms. This paper introduces fundamental concepts in digital remote sensing and describes numerous applications of the technology. The intent is to provide a balanced, nontechnical view, discussing the shortcomings, successes, and future potential for digital remote sensing of forested ecosystems.     

Risk-Based Analysis of Environmental Monitoring Data: Application to Heavy Metals in North Carolina Surface Waters

The state of North Carolina's Department of Environment and Natural Resources (NCDENR) conducts routine water quality monitoring throughout the state to assess the health of aquatic systems. The current study reports the results of a retrospective (1990–2000) ecological risk assessment of six heavy metals (arsenic, cadmium, copper, lead, mercury, and zinc) in 17 North Carolina basins that was conducted to estimate the risk of heavy metal toxicity to freshwater organisms and assess the sufficiency of NCDENR's monitoring data to identify water-quality-related ecological threats. Acute and chronic ecotoxicological thresholds (ETs) were calculated for each metal based upon the 10th percentile of species sensitivity distributions and were normalized for water hardness. Statewide probabilities (expressed as percentages) of a random sample exceeding acute or chronic ETs among the six metals ranged from 0.01% to 12.19% and 0.76% to 21.21%, respectively, with copper having the highest and arsenic and mercury the lowest risk. Basin-specific probabilities varied significantly depending upon water hardness and presumably watershed development. Although the majority of specific sites where data were collected were at low risk for metal toxicity, some specific sites had a high probability of toxic events associated with one or more metals. Analytical detection limits for metals were frequently higher than estimated chronic ET, limiting the ability to assess the risk of chronic toxicity in soft-water basins. Results suggest risk-based criteria may be useful for assessing and validating the sufficiency of monitoring programs and prioritizing management goals.     

Farmers' involvement in landscape activities: an analysis of the relationship between farm location, farm characteristics and landscape changes in two study areas in Jutland, Denmark

Farmers are important agents in rural landscape management as they modify landscape elements to suit their needs. The purpose of this study is to investigate if patterns of landscape activities undertaken by farmers are related to certain farm characteristics and if landscape activities vary from one location to another. With this purpose, we investigated the differences between the level of farmers' involvement in landscape activities in two study areas in central Jutland, Denmark. Particular attention was given to the analysis of the type and extent of landscape activities and their relationship with farm characteristics. In both study areas, landscape activities leading to a more extensive type of land use predominate. However, a multivariate analysis implemented on the set of landscape activity data reveals significant differences between the two study areas. Hedgerow planting and removal is more common in S?nder Omme, while pond digging and cultivation of permanent grass lands are characteristic activities in Gadbjerg-Givskud. Moreover, the proportion of farmers involved and the area affected by different landscape activities is larger in S?nder Omme than in Gadbjerg-Givskud. The farms of the two areas are different in terms of production type, size and socio-economic characteristics. These characteristics represent significant relationships with landscape activities. However, they are not sufficient to explain the differences between landscape activities undertaken in the two areas. The differences are caused by unique cultural and biophysical environment, which influence and modify the relationship between farm characteristics and landscape activities in a distinct manner for each study area.     

Population viability analysis as a tool in wildlife conservation policy: With reference to Australia

Wildlife conservation policy for endangered species restoration follows a six-phase process. Population viability analysis (PVA) can play a major contributing role in four of these. PVA, as discussed here, is a technique where extinction vulnerabilities of small populations are estimated using computer simulation modeling. The benefits and limitations of using PVA in wildlife decision and policy processes are reviewed based on our direct experience. PVA permits decision makers to set time frames for management, estimate the required magnitude of restoration efforts, identify quantitative targets for species recovery, and select, implement, monitor, and evaluate management strategies. PVA is of greatest value for rare species policy and management. However, a limitation of PVA simulation models is that they are constrained by the amount of biological data available, and such data are difficult to obtain from small populations that are at immediate risk of extinction. These problems may be overcome with improved models and more data. Our experience shows benefits of PVA far outweigh its limitations, and applications of the approach are most useful when integrated with decision analysis and completed within an adaptive management philosophy. PVAs have been carried out for 14 Victorian species and less used elsewhere in Australia. Management and recovery plans are developed from these PVAs. We recommend that PVA be used to guide research programs, develop conservation strategies, and inform decision and policy making for both endangered and nonendangered species because it can significantly improve many aspects of natural resource policy and management.     

Application of a cave inventory system to stimulate development of management strategies: the case of west-central Florida, USA

The active management of air-filled cave systems is virtually non-existent within the karst landscape of west-central Florida. As in every karst landscape, caves are important because they contain a wide variety of resources (e.g., biota, speleothems) and can act as direct connections between surface and subsurface hydrological processes, potentially exacerbating the pollution of groundwater. Before sound management policies can be drafted, implemented, and enforced, stakeholders must first have knowledge of the management requirements of each cave. However, there is an informational disconnect between researchers, stakeholders, and the recreational caving community. Here, we present a cave inventory system that simplifies the dissemination of resource knowledge to stakeholders so that cave management and protection policies can be drafted and implemented at the state and local level. We inventoried 36 caves in west-central Florida, located on both public and private land, and analyzed cave resource data to provide insights on cave sensitivity and disturbance using two standardized indices. The data revealed that both public and private caves exhibit a wide range of sensitivity and disturbance, and before management strategies can be drafted, the ownership of each cave must be considered. Our inventory geodatabase serves as a link between researchers, landowners, and the public. To ensure the conservation and protection of caves, support from county or state government, combined with cave inventory data, is crucial in developing sound management policy.     

Towards an Integrated Approach to Natural Hazards Risk Assessment Using GIS: With Reference to Bushfires

This paper develops a GIS-based integrated approach to risk assessment in natural hazards, with reference to bushfires. The challenges for undertaking this approach have three components: data integration, risk assessment tasks, and risk decision-making. First, data integration in GIS is a fundamental step for subsequent risk assessment tasks and risk decision-making. A series of spatial data integration issues within GIS such as geographical scales and data models are addressed. Particularly, the integration of both physical environmental data and socioeconomic data is examined with an example linking remotely sensed data and areal census data in GIS. Second, specific risk assessment tasks, such as hazard behavior simulation and vulnerability assessment, should be undertaken in order to understand complex hazard risks and provide support for risk decision-making. For risk assessment tasks involving heterogeneous data sources, the selection of spatial analysis units is important. Third, risk decision-making concerns spatial preferences and/or patterns, and a multicriteria evaluation (MCE)-GIS typology for risk decision-making is presented that incorporates three perspectives: spatial data types, data models, and methods development. Both conventional MCE methods and artificial intelligence-based methods with GIS are identified to facilitate spatial risk decision-making in a rational and interpretable way. Finally, the paper concludes that the integrated approach can be used to assist risk management of natural hazards, in theory and in practice.     

A method to assess the allocation suitability of recreational activities: An economic approach

Most existing methods of planning focus on development of a recreational area; less consideration is placed on the allocation of recreational activities within a recreational area. Most existing research emphasizes the economic benefits of developing a recreational area; few authors assessed the allocation suitability of recreational activities from an economic point of view. The purpose of this work was to develop a model to assess the allocation suitability of recreational activities according to the application of a concept of analysis of cost and benefit under a premise of ecological concern. The model was verified with a case study of Taiwan. We suggest that the proposed model should form a critical part of recreational planning.     

A GIS-based approach for assessing the regional conservation status of genetic diversity: an example from the southern Appalachians

Conserving genetic diversity requires an assessment of the distribution of genetic variants in relation to patterns of land use and environmental variation at a regional scale. This assessment requires a novel approach to integrating and analyzing the genetic and environmental data across spatial scales. To explore the integration of genetic data with other geospatial data sets, we developed a GIS-based approach for examining patterns of genetic diversity for several species of salamanders in southern Appalachians. The genetic data, from allozyme surveys in the genetics literature, were integrated into a GIS database along with related attributes including population identifications and spatial locations. Using existing geospatial data, we classified sample locations as being either protected from anthropogenic disturbance (e.g., National Parks, Wilderness Areas) or as unprotected (e.g., private lands, multiple-use lands in National Forests). We used multidimensional scaling of allelic frequencies and contributions of populations to interpopulation differences in allelic richness to determine which populations had genetic characteristics most different from other populations in the sample. Measures of genetic differentiation were integrated into the GIS database to facilitate spatial analysis and visualization of the indices in relation to land use. This approach was useful for both identification of populations with components of genetic variation that were not well represented at protected sites and for identifying areas of species distributions where more genetic sampling would be necessary to make informed management decisions. Our approach could be readily adapted for use by managers and geneticists working with other species and types of genetic markers.     

Shifting paths to conservation: policy change discourses and the 2008 US farm bill

From 2004 until 2006, reform of US agricultural subsidy programmes seemed a likely result of pressure from the World Trade Organization. Many groups saw this pressure as an opportunity to ‘green’ farm policy by crafting environmental service payments that could replace crop subsidies. Yet the 2008 US farm bill fell short of such drastic changes. This paper uses discourse analysis to trace the decline of prospects for reform of the farm bill, and a shift to incremental policy making between 2006 and 2008. It finds that, in addition to political and situational factors, striking discursive shifts altered policy debates and outcomes to create particular conservation impacts. It thus argues for broader use of rhetoric theory and discourse analysis to assess environmental policy. Implications for land conservation are presented in the context of interest group tactics.     

Forest planning in an Oregon case study: Defining the problem and attempting to meet goals with a spatial-analysis technique

Five major management goals were identified for the upper Grande Ronde River Basin on the Wallowa-Whitman National Forest in northeastern Oregon: to produce high-quality fish habitat, to maintain elk habitat, to restore and maintain forest conditions within the natural range of viability, and to contribute to community economic stability. From the broad goals, specific goals for stream temperature, habitat effectiveness index (HEI), habitat corridors, maintenance of land in late or old seral stages, and a nondeclining even flow of timber were selected. A case study was undertaken in a small watershed that is under typical societal constraints to determine whether one decisionsupport tool, SNAP II+, could evaluate the selected goals in a single planning exercise. Three riparian management strategies and two forest road scenarios were used. The exclusion of harvest and road-building from riparian zones in order to increase habitat protection decreased harvest levels and net present value but maintained preactivity stream temperatures. Other resources were generally maintained within prescribed management levels. Although the technique has limitations (e.g., it does not account for riparian zones in calculations of forage and cover for HEI, and it can use the maximum but not minimum acreage goal for some resources), it shows promise for evaluating management tradeoffs in watershed analysis.This is Paper 3069 of the Forest Research Laboratory, Oregon State University, Corvallis, Oregon.     

Evaluating the impact of water conservation on fate of outdoor water use: a study in an arid region

In this research, the impact of several water conservation policies and return flow credits on the fate of water used outdoors in an arid region is evaluated using system dynamics modeling approach. Return flow credits is a strategy where flow credits are obtained for treated wastewater returned to a water body, allowing for the withdrawal of additional water equal to the amount returned as treated wastewater. In the return credit strategy, treated wastewater becomes a resource. This strategy creates a conundrum in which conservation may lead to an apparent decrease in water supply because less wastewater is generated and returned to water body. The water system of the arid Las Vegas Valley in Nevada, USA is used as basis for the dynamic model. The model explores various conservation scenarios to attain the daily per capita demand target of 752 l by 2035: (i) status quo situation where conservation is not implemented, (ii) conserving water only on the outdoor side, (iii) conserving water 67% outdoor and 33% indoor, (iv) conserving equal water both in the indoor and outdoor use (v) conserving water only on the indoor side. The model is validated on data from 1993 to 2008 and future simulations are carried out up to 2035. The results show that a substantial portion of the water used outdoor either evapo-transpires (ET) or infiltrates to shallow groundwater (SGW). Sensitivity analysis indicated that seepage to groundwater is more susceptible to ET compared to any other variable. The all outdoor conservation scenario resulted in the highest return flow credits and the least ET and SGW. A major contribution of this paper is in addressing the water management issues that arise when wastewater is considered as a resource and developing appropriate conservation policies in this backdrop. The results obtained can be a guide in developing outdoor water conservation policies in arid regions.