The world agricultural system and ethical considerations relating to the rural environment: Some perspectives on cause and effect in underdeveloped countries

Food is a basic human need and therefore a basic human right. While food output has increased to a level where there is enough food produced to feed the world, still millions starve. Using the concept of capitalist world economy as a framework, this paper provides a structural analysis of the food production and distribution system within monopoly capitalism and its implications for countries of the underdeveloped world. Focusing on the impact of a dominant world food supply system on indigenous systems (particularly through the rise of science, technology, and monopoly capital), considerations relating to environmental use and food production and distribution are raised. Finally a call is made for a new agricultural ethic.     

建设项目环境影响的医学评价方法研究

作者在对中国我人民解放军第４７医院病建项目所产生的大气环境影响进行了医学秤价和影响，并在预测的基础上，建立了完整的环境医学影响廉政价方法，由于该评价方法完全尊循了国内现行大气环境影响评价的基本要求和程序，因此，它在今后的环境影响医学评价中净有广泛的应用。     

ANALYSIS OF WIND- AND SHIP-INDUCED SEDIMENT RESUSPENSION IN DULUTH-SUPERIOR HARBOR1

ABSTRACT: Suspended solids and ammonium concentration profiles measured at five locations in Duluth-Superior Harbor during July-October 1985 were analyzed to quantify wind and ship effects on sediment resuspension and resulting harbor water quality. Wind components from the SE quadrant correlated strongly with depth-averaged suspended solids concentrations that were unaffected by ship passage or thermal stratification. Winds from that quadrant have the largest fetch in the harbor. The highest correlation (r²= 0.93) was with the 6-hour average of the ESE wind velocity component. Multiple linear regression analysis of data from post-ship passage concentration profiles yielded numerical estimates of settling velocities of 0.08 to 0.25 cm s^?1, typical of ship-resuspended sediments, and vertical eddy diffusivities of 4 to 13 cm² s¹. The results suggest that ambient vertical eddy diffusivities in the harbor are less than 4 cm² s^?1 in the absence of ship passages and with winds less than 5 m s^?1 (10 knots).     

Microbial degradation of poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) in compost

The microbial degradation of tensile test pieces made of poly(3-hydroxybutyrate) [P(3HB)] or copolymers with 10% [P(3HB-co-10%3HV)] and 20% [P(3HB-co-20%3HV)] 3-hydroxyvaleric acid was studied in small household compost heaps. Degradation was measured through loss of weight (surface erosion) and changes in molecular weight and mechanical strength. It was concluded, on the basis of weight loss and loss of mechanical properties, that P(3HB) and P(3HB-co-3HV) plastics were degraded in compost by the action of microorganisms. No decrease inM _w could be detected during the degradation process. The P(3HB-co-20%3HV) copolymer was degraded much faster than the homopolymer and P(3HB-co-10%3HV). One hundred nine microbial strains capable of degrading the polymersin vitro were isolated from the samples used in the biodegradation studies, as well as from two other composts, and identified. They consisted of 61 Gram-negative bacteria (e.g.,Acidovorax facilis), 10 Gram-positive bacteria (mainlyBacillus megaterium), 35Streptomyces strains, and 3 molds.     

Changes in wetlands on nonfederal rural land of the conterminous United States from 1982 to 1987

Recent wetland area trends were estimated from the National Resources Inventory (NRI) for nonfederal rural lands for the period 1982–1987. NRI-based estimates of wetland area for states comprising the conterminous United States were highly correlated with estimates made by the US Fish and Wildlife Service and with estimates of coastal salt marsh wetlands made by the National Oceanic and Atmospheric Administration. Net wetland area declined by 1.1% (≈363,200 ha) during the five-year study period. Conversion to open water, primarily caused by natural flooding in western inland basins, was responsible for altering extensive wetland areas (≈171,400 ha). Of the human-induced wetland conversions, urban and built-up land was responsible for 48% of the wetland loss, while agricultural development was indicated in 37% of the converted wetland area. A decrease in rural land, and increases in both population, and urban and built-up land were associated with wetland loss among states. Potential reasons for wetland loss were different in 20 coastal states than in 28 inland states. Proportionately, wetland loss due to development was three times greater in coastal states than inland states, while agriculturally induced wetland losses were similar in both groups. The proportionate declines of forested vs nonforested wetlands were not significantly different among states.     

Ecologically derived guidelines for managing two New Zealand lakes

Lakes Manapouri and Te Anau, in Fiordland National Park, became the center of a major controversy after the New Zealand government offered their water resource to an overseas aluminum smelting consortium for electricity generation. Although the scheme proceeded, the lake levels were not raised as originally proposed. Rather, government sought guidelines to optimize hydroelectric potential while maintaining ecological stability of the vulnerable, largely forested, glaciated lakeshores. Guidelines were derived by relating the vegetation zonation to the natural lake-level fluctuations recorded daily for 37 years. Ahigh operating range in the upper third of the lakes' natural ranges, based on flood tolerances of the woody shoreline species, restricts both duration and frequency. Alow operating range (ca. lower third) safeguards stability of shoreline sediments by limiting drawn-down rates, duration, and frequency. Themain operating range (ca. middle third) has few limitations. These guidelines, which allow utilization of ca. 93% of the water resource, have now been verified by instances of flooding and draw-down rates that exceeded the natural rates recorded earlier. The guidelines were officially accepted by the government in 1977 as a basis for managing the valuable multiple resources of these two lakes and their environs, and they were formalized in legislation in 1981. The details and merits of the guideline approach are discussed.     

Title 16 united states code §55 and its implications for management of concession facilities in Yosemite National Park

Yosemite National Park is one of the nation's most scenic and ecologically/geologically important parks. Unfortunately, the park is subject to extensive development of concession facilities and associated high levels of visitor use. Those concerned with preservation of the park's resources have attempted to limit the types and extent of such facilities to reduce adverse impacts. Strictly speaking, resolution of the preservation versus use controversy must be based on whether the National Park Service is adhering to its legislative mandate to regulate development and use in the parks. The common interpretation of legislative mandates for national parks, including Yosemite, is that they call for a difficult balancing between the conflicting goals of preservation and use. Accordingly, although concession developments cause significant impacts, they usually have been interpreted to be within the legal discretion allowed the secretary of the interior. However, the usual interpretations of the meanings of legislative mandates for Yosemite National Park have not considered Title 16 United States Code §55, which is a very restrictive statute limiting concession facilities. Many of the limitations imposed on concession facilities by the plain language of the statute have been exceeded. If it can be shown that 16 United States Code §55 is a valid statute, the policy implications for park management in Yosemite National Park would be considerable — namely, that significant reductions in concession facilities could be required. This article examines whether the statute can reasonably be thought to be valid and encourages others to conduct further examination of this question.     

External threats to ecosystems of US national parks

Activities beyond national park boundaries are now the principal source of threats to park natural resource integrity. Assessing the full impact of major threats as air and water pollution requires a long-term ecosystem-level approach in research design and execution, and park management. Failure to take such an approach renders most existing park data bases useless in the documentation of external threats. While the concept of managing national parks as ecosystems is not new, Park Service research and its organization have not provided the information necessary for such a basis of management. Quantifying the impacts on park resources due to external hydrologic regulation and air pollution is a good example of the need to employ an ecosystem approach in research. However, implementing such a program will require a fundamental change in research administration, priority setting, and conceptual approach.The first four of the articles in this special section arise from an AAAS symposium onExternal Threats to Ecosystems of the National Parks in the USA, which was convened in 1982. The articles have been revised to reflect subsequent developments in this field. The first article, by Dr. Stottlemyer, the symposium organizer, serves as an introduction to the topic. The fifth article in this special section was submitted separately, but included because it also is related to this particular topic.     

Legal considerations in challenging external threats to Glacier National Park,Montana, USA

External threats to the environmental integrity of Glacier National Park, Montana, USA, fit into three categories: adverse land use practices adjacent to the Park, air pollution, and water pollution. This article identifies and evaluates the laws that Glacier National Park officials might rely upon to protect the Park against these external threats. The article also assesses the available scientific information relating to external threats, and it identifies additional information needed to establish a legal basis for challenging the threats.     

ASSESSING FLUSHING-FLOW REQUIREMENTS FOR BROWN TROUT SPAWNING GRAVELS IN STEEP STREAMS1

Flushing flows are re1eses from dams designed to remove fine sediment from downstream spawning habitat. We evaluated flushing flows on reaches proposed for hydroelectric diversions on seven streams in the eastern Sierra Nevada, California, with wild populations of brown trout (Salmo trutta). The stream reaches are steep (average map slopes range from 7 to 17 percent), are dominated by boulder cascades, and afford few opportunities for gravel deposition. Methods for estimating flushing flows from flow records, developed from studies in other localities, produced widely differing results when applied to the study streams, probably reflecting differences in the hydrologic and geomorphic characteristics of the streams on which the methods were developed. Tracer gravel experiments demonstrated that all sampled gravels were washed out by the flows of 1986, a wet year. Size analyses of gravel samples and hydraulic data from field surveys were used in tractive-force calculations in an attempt to specify the flow required to flush the gravels. However, these calculations produced some unrealistic results because the flows were nonuniform in the study reaches. This suggests that the tractive-force approach may not be generally applicable to small, steep streams where nonuniform flow conditions prevail.