Monitoring the fate of chlorine from MSW sampling through combustion Part I: Analysis of the waste stream for chlorine

The total chlorine and water soluble chlorine contents of the components of municipal solid waste (MSW) have been determined from sampling studies carried out at two sites, Baltimore County, MD, and Brooklyn, NY, for a five-day period. The total chlorine contents of the MSW samples from Baltimore County, MD, and Brooklyn, NY, are 0.45 and 0.89 mass %, respectively.     

Bedding and seasonal effects on chemical and bacterial properties of feedlot cattle manure

Nutrients, soluble salts, and pathogenic bacteria in feedlot-pen manure have the potential to cause pollution of the environment. A three-year study (1998-2000) was conducted at a beef cattle (Bos taurus) feedlot in southern Alberta, Canada to determine the effect of bedding material [barley (Hordeum vulgare L.) straw versus wood chips] and season on the chemical and bacterial properties of pen-floor manure. Manure was sampled for chemical content (N, P, soluble salts, electrical conductivity, and pH) and populations of four groups of bacteria (Escherichia coli, total coliforms, and total aerobic heterotrophs at 27 and 39 degrees C). More chemical parameters of manure were significantly (P < or = 0.05) affected by season (SO4, Na, Mg, K, Ca, sodium adsorption ratio [SAR], total C, NO3-N, NH4-N, total P, and available P) than by bedding (K, pH, total C, C to N ratio, NH4-N, and available P). Bedding had no significant (P > 0.05) effect on the four bacterial groups whereas season affected all four groups. Numbers of E. coli and total coliforms (TC) were significantly higher by 1.72 to 2.02 log10 units in the summer than the other three seasons, which was consistent with a strong positive correlation of E. coli and TC with air temperature. The low ratio of bedding to manure in the pens was probably the major cause of the lack of significant bedding effects. Bedding material and seasonal timing of cleaning feedlot pens and land application of manure may be a potential tool to manage nutrients, soluble salts, and pathogens in manure.     

Anthropogenic Disturbance and Patch Dynamics in Circumpolar Arctic Ecosystems

Abstract: It has been 30 years since environmental concern was first expressed over the prospect of large-scale resource development in the Arctic. Human effects are more extensive within the tundra biome now than at any time in the past. With or without predicted climatic changes, interaction among different natural and contemporary anthropogenic disturbance regimes are bound to have a significant effect on local and regional vegetation patterns and plant migration. We summarize the results of recent studies of patchy anthropogenic disturbance. We pay particular attention to the natural regeneration of plant communities, emphasize patch dynamics over the medium term (20–75 years), and discuss the data in the context of popular models of vegetation change following disturbance. Disturbance is important because it produces patches of partially or totally denuded ground that permit propagule establishment but may also open affected areas to erosion. Even relatively low-intensity, small-scale disturbances have immediate and persistent effects on arctic vegetation and soils. On all but the wettest sites, the patches support new, relatively stable vegetation states. Where slope is minimal, such disturbances are capable of expanding over large areas in as short a time as 4 years. The effects result in an artificial mosaic of patches of highly variable quality and quantity that comprise feeding and nesting habitats for terrestrial herbivores.     

A method for scaling biological response of soil microcosms

An extensive series of laboratory experiments was conducted in soil microcosms to study the respiratory response of microorganisms to toxicant amendments within different types of soils. Our analysis of test results demonstrates that coupled biological and environmental factors within soil can be scaled (i.e., commensurably and analogously grouped) by means of two rate constants, one characterizing the diffusion of CO₂ in the soil matrix and another the biological production of CO₂. The two rate constants were used to classify the impact of metal compounds on diverse soil types and to predict the loss or gain of total respiratory CO₂ of amended soils relative to intact soils. This method exemplifies a more general approach, potentially useful for scaling complex physical and biological interactions in environmental assessments.     

Sustainable rural development in Sokoto State, Nigeria

In Nigeria, as in most countries, institutional barriers to successful rural development exist and need to be addressed. In Sokoto State, a variable and unpredictable Sahelian climate in combination with conditions of high population growth, low levels of income, and environmental degradation, create and intensify institutional challenges. This study examines the sustainability of government initiatives regarding the provision of agricultural inputs, assistance and extension services to farmers, and the extent to which agency efforts are coordinated and integrated, particularly regarding water management. In some cases, rural development agencies demonstrated the capability to meet the needs of the people. Some farmers were satisfied with government assistance and in some areas the tube well programme was quite successful. Yet in Sokoto State many institutional barriers to sustainable rural development exist and need to be addressed. In general, implementation strategies and management procedures appeared narrowly focused and placed little emphasis on coordination and integration among rural development agencies. The result was often inappropriate overlap or oversights in activities .     

Environmentally conscious product design through total quality management

The actions of governments, customers, and competitors are influencing corporate environmental management in unprecedented ways. Market requirements are affecting both revenues and costs in ways that individual firms cannot control. The uncertainty that these new requirements create underscores the critical importance of planning and implementing a systematic approach to the design of products and the processes used to build, ship, support, and recover them. In this article the author shows how Total Quality Management offers a useful framework for aligning a company'S market focus, its business plans, and its management of critical business processes. This alignment is critical, if companies are to create environmentally conscious products while remaining competitive in a global marketplace.     

Impact of riverine wetlands construction and operation on stream channel stability: Conceptual framework for geomorphic assessment

Wetland conservation is a critical environmental management issue. An emerging approach to this issue involves the construction of wetland environments. Because our understanding of wetlands function is incomplete and such projects must be monitored closely because they may have unanticipated impacts on ecological, hydrological, and geomorphological systems. Assessment of project-related impacts on stream channel stability is an important component of riverine wetlands construction and operation because enhanced erosion or deposition associated with unstable rivers can lead to loss of property, reductions in channel capacity, and degradation of water quality, aquatic habitat, and riparian aesthetics. The water/sediment budget concept provides a scientific framework for evaluating the impact of riverine wetlands construction and operation on stream channel stability. This concept is based on the principle of conservation of mass, i.e., the total amount of water and sediment moving through a specific reach of river must be conserved. Long-term measurements of channel sediment storage and other water/sediment budget components provide the basis for distinguishing between project-related impacts and those resulting from other causes. Changes in channel sediment storage that occur as a result of changes in internal inputs of water or sediment signal a project-related impact, whereas those associated with changes in upstream or tributary inputs denote a change in environmental conditions elsewhere in the watershed. A geomorphic assessment program based on the water/sediment budget concept has been implemented at the site of the Des Plaines River Wetlands Demonstration Projection near Chicago, Illinois, USA. Channel sediment storage changed little during the initial construction phase, suggesting that thus far the project has not affected stream channel stability.     

A strategy for integrated monitoring

Administrative machinery has been set up to regulate and control most of the emissions that are known to have severe local consequences, such as the discharge of raw sewage into rivers and lakes and the smokestack emission of air pollutants. Now, the nature of environmental degradation is usually different. We are faced with pollutants and effects with more subtle cause-effect relationships, often characterized by larger geographic areas of interest and longer term potential damage; the potential risk is now more chronic than acute. Acid rain and climate change are good examples, in that they are associated with a variety of pollutants from a number of sources and damage to ecosystems occurs over many years. It is argued that monitoring programs should evolve to reflect the changing nature of the environmental problems they are addressing. It is now necessary to consider interactions among many pollutants, mixing among the various media, and potentially affecting many components of the ecosystem in both indirect and direct ways. Here, integrated monitoring and analysis is presented as a unifying strategy to bring together different measurement methodologies in different disciplines, addressing environmental questions of complexity beyond the scope of many existing activites that have a classical narrower focus. The underlying concept is of nested networks, each tier being composed of sites selected for specific purposes but arranged to maximize the number of common sites where more multidisciplinary questions can be addressed.