OPTIMIZATION OF WATER ALLOCATION DECISIONS AFFECTING ESTUARINE ECOLOGY1

ABSTRACT .The problem analyzed in this paper is how to allocate optimally the available surface water in a river system among those who compete for its use, while acknowledging explicitly that for coastal states the ecology of bays and estuaries must be numbered among the competitors. The objective is to maximize the benefit resulting from water use while satisfying a set of constraints on flow. Benefit is assumed to be a function of the amount of water used and the time period in which the water is used. A mathematical model of this problem is shown to fit the format of the minimum cost circulation network flow problem. The Out-of-Kilter algorithm of D. R. Fulkerson is proposed as a solution technique. Sensitivity analysis on the input data is described as a means of determining the minimum economic benefit required to justify the allocation of a given volume of water needed to sustain the ecology of an estuary.     

APPLICATION OF A HYDROLOGIC MODEL FOR LAND USE PLANNING IN FLORIDA1

ABSTRACT: An environmental simulation model of the Upper St. Johns River Basin, Florida, has been developed in order to predict hydrologic responses under proposed management plans. Land use projections for each of 19 hydrologic planning units are provided by a linear programming analysis of agricultural activities. Inputs to the model include rainfall, runoff, evapotranspiration (ET), aquifer properties, topography, soil types, and vegetative patterns. A water balance is developed in the uplands based on infiltration, ET, surface runoff, and groundwater flow. Valley continuity is based on stage-volume relationship for inflows and outflows and a variable roughness coefficient dependent on vegetative patterns. Land use changes form the basis for predicting hydroperiod variation under alternative management schemes. Plans are ranked according to two criteria, deviation from a natural hydroperiod and flood or drought control provided. Results indicate that (1) a single reservoir without irrigation and (2) floodplain preservation plans are superior to (3) multiple reservoir with irrigation and (4) uncontrolled floodplain plans with regard to both criteria.     

Landscape Trends in Mid-Atlantic and Southeastern United States Ecoregions

Landscape pattern and composition metrics are potential indicators for broad-scale monitoring of change and for relating change to human and ecological processes. We used a probability sample of 20-km × 20-km sampling blocks to characterize landscape composition and pattern in five US ecoregions: the Middle Atlantic Coastal Plain, Southeastern Plains, Northern Piedmont, Piedmont, and Blue Ridge Mountains. Land use/land cover (LULC) data for five dates between 1972 and 2000 were obtained for each sample block. Analyses focused on quantifying trends in selected landscape pattern metrics by ecoregion and comparing trends in land cover proportions and pattern metrics among ecoregions. Repeated measures analysis of the landscape pattern documented a statistically significant trend in all five ecoregions towards a more fine-grained landscape from the early 1970s through 2000. The ecologically important forest cover class also became more fine-grained with time (i.e., more numerous and smaller forest patches). Trends in LULC, forest edge, and forest percent like adjacencies differed among ecoregions. These results suggest that ecoregions provide a geographically coherent way to regionalize the story of national land use and land cover change in the United States. This study provides new information on LULC change in the southeast United States. Previous studies of the region from the 1930s to the 1980s showed a decrease in landscape fragmentation and an increase in percent forest, while this study showed an increase in forest fragmentation and a loss of forest cover.     

Landscape Changes in the Mullica River Basin of the Pinelands National Reserve,New Jersey,USA

In 1979, the Pinelands Commission was established as a regional land-use planning and regulatory agency charged with the implementation of a Comprehensive Management Plan (CMP) for the Pinelands National Reserve (New Jersey, USA). The CMP was created to balance land preservation and development interests in the Reserve. Because water-quality degradation from developed and agricultural landscapes is associated with changes in the composition of biological communities, monitoring landscape changes provides one of the most direct measures of the impact of land-use policies on the Pinelands ecosystem. In this study, we prepared detailed, land-cover maps within randomly selected aerial-photograph plots for a major watershed in the Reserve. We used these land-cover maps to quantify changes in landscape composition and structure (i.e., patch size, patch area, and number of patches) and characterize land-cover transitions in the basin between 1979 and 1991. Because the study period represented the first 12 years of the regional-planning effort in the Reserve, we evaluated the relationship between land-cover transitions and Commission management-area designations which permit different land-use intensities. Although the landscape composition was similar in 1979 and 1991, we found an increase in the total area and number of developed-land, managed-grassland, and barren-land patches. An increase in the number of patches and a decrease in the total area and median and third-quartile patch sizes for forest land and for all patches regardless of cover type indicated that fragmentation of forest land and the landscape as a whole occurred during the study period. The major land-cover transitions that occurred during the period were the loss of forest land to development and associated cover types and the conversion of one agricultural type to another. Overall, land-cover transitions during the period were found to be consistent with the Commission management-area designations, which indicated that the regional-planning effort has been successful in directing human activities to appropriate areas of the basin.     

安徽"两山一湖"地区的旅游生态破坏和视觉污染问题

阐述了“两山一湖”地区在安徽省旅游中的重要地位,重点讨论了“两山一湖”地区的旅游生态破坏和视觉污染问题。     

Industrial ecosystem evolution of North Karelia heating energy system

Within the emerging concept of industrial ecology (IE) that belongs to the research and practical field of sustainable development (SD), the natural ecosystem evolution over time has been described as a metaphor that presents systems of type I, type II and type III ecology. Type I describes a situation when there was little life on earth and plenty of resources. In type II, the ecosystem starts to develop material cycles and energy cascades between organisms and species due to increasing amount of life and emerging scarcity of resources. In type III, the mature ecosystem stage, the system actors have developed nearly completely cyclic flows of matter, energy cascades and diverse interdependencies between them. This paper uses the metaphor in the three systems to develop practical models of type I, II and III industrial ecosystems for an economic system of heating energy and its evolution over time. First, the physical flows of matter and energy are described by using two contrasting case system characteristics, 'throughput' and 'roundput'. Throughput means linear material and energy flows. Roundput means material cycles, energy cascades and sustainable use of renewables, i.e., ecosystem type III. Second, the more structural and organisational features are considered with the characteristic of 'diversity' meaning diversity in resources, human involvement and economic actors and technology used. The case system development over time shown with our practical model of type I–III is radically different from the ecosystem evolution as described in the literature on the industrial ecosystem metaphor of type I–III. This conclusion as a research result, however, is tentative, because of the fuzzy and vague meaning assigned to a metaphor and its confusion with a practical model of industrial development in the industrial ecology literature.     

Cross-Boundary Cooperation in a Watershed Context: The Sentiments of Private Forest Landowners

Ecosystem management and sustainable forestry on mixed ownership landscapes will require some level of cross-boundary coordination or management. Oregon's experiment with local, voluntary, collaborative forums, called watershed councils, is one mechanism to foster cross-boundary management. Fifty qualitative, in-depth interviews in three study areas were conducted with nonindustrial private forest (NIPF) landowners, watershed council members, and agency employees to learn how and why landowners participate (or not) on watershed councils. Study areas were located in three different areas of the state to reflect different ecological and organizational settings. Our case study identified three themes—stewardship ethic, property rights amid uncertainty, and action orientation—that were most salient among landowners when deciding to participate in their local watershed council. Other factors related to competing opportunities were also identified. Our results relate to the social psychological antecedents to cooperation of perceived consensus, group identity, and legitimacy of authority as well as to applied situations where cross-boundary coordination and management are goals.     

Road traffic and nearby grassland bird patterns in a suburbanizing landscape

An extensive road system with rapidly increasing traffic produces diverse ecological effects that cover a large land area. Our objective was to evaluate the effect of roads with different traffic volumes on surrounding avian distributions, and its importance relative to other variables. Grassland bird data (5 years) for 84 open patches in an outer suburban/rural landscape near Boston were analyzed relative to: distance from roads with 3000–8000 to >30,000 vehicles/day; open-habitat patch size; area of quality microhabitat within a patch; adjacent land use; and distance to other open patches. Grassland bird presence and regular breeding correlated significantly with both distance from road and habitat patch size. Distance to nearest other open patch, irrespective of size, was not significant. Similarly, except for one species, adjacent land use, in this case built area, was not significant. A light traffic volume of 3000–8000 vehicles/day (local collector street here) had no significant effect on grassland bird distribution. For moderate traffic of 8000–15,000 (through street), there was no effect on bird presence although regular breeding was reduced for 400 m from a road. For heavier traffic of 15,000–30,000 (two-lane highway), both bird presence and breeding were decreased for 700 m. For a heavy traffic volume of ≥30,000 vehicles/day (multilane highway), bird presence and breeding were reduced for 1200 m from a road. The results suggest that avian studies and long-term surveys near busy roads may be strongly affected by traffic volume or changes in volume. We conclude that road ecology, especially the effects extending outward >100 m from roads with traffic, is a sine qua non for effective land-use and transportation policy.     

Environmental Effects of In Situ Burning of Oil Spills in Inland and Upland Habitats

In situ burning of inland and upland habitats is an alternative oil spill cleanup technique that, when used appropriately, may be more environmentally acceptable than intrusive manual, mechanical, and chemical treatments. There have been few published reports documenting the environmental effects of in situ burning in inland and upland habitats. Thus, this study, sponsored by the American Petroleum Institute, used two approaches to increase the knowledge base and improve the appropriate use of in situ burning: (1) detailed review of published and unpublished in situ burn case histories for inland and upland spills; and (2) summaries of fire effects and other information from the literature on fire ecology and prescribed burning. Thirty-one case histories were summarized to identify the state of the practice concerning the reasons for burning, favorable conditions for burning, and evaluations of burn effects. The fire ecology and effects summaries included information from the extensive knowledge base surrounding wildfire and prescribed burning (without oil) as a natural resource management tool, as well as fire tolerance and burning considerations for dominant vegetation types of the United States. Results from these two approaches should improve the application of in situ burning for inland and upland spills.     

林火对景观格局的影响及其应用

通过查阅国内外有关林火与景观生态学的资料，综述了景观对林火的可能响应过程，从景观尺度上，分析了林火干扰对景观的结构、功能、动态、格局及多样性规律的双重影响。分析了景观格局对林火的影响，阐述了林火与景观的相互关系，列举了林火在景观生态学研究中的作用。