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.     

ADVANTAGES AND DISADVANTAGES OF REGIONAL SEWERAGE SYSTEMS1

ABSTRACT: A few years ago, many water quality administrators were convinced that large regional sewerage systems, consisting of one large treatment plant and long trunk sewers extending out to various communities, represented the only efficient and economical means of assuring water quality control. In communities favoring rapid development, the provision of sewer service and encouragement of development of new centers along the trunk sewers offered an additional advantage. More recently quite different points of view are arising in certain areas. In parts of New Jersey strong environmental and community resistance has arisen to proposed central plant-trunk sewer systems. The facilitation of new development along the trunk sewers is viewed as a menace by townships not wanting intensive development of these areas. The diversion of effluent flows to trunk sewers rather than septic tanks would dry up the streams which water quality programs are supposed to protect. Both sides to the controversy have mobilized engineering, environmental, economic, and legal expertise and some critical policy issues have developed. Reconsideration of regional sewerage management and particularly trunk sewer policy is required. The decision as to extent of sewerage service areas involves complex and sensitive planning issues. Because of potential conflicts of interest, such decisions should not be left to staffs of sewerage authorities and their design engineers.     

WATER YIELD IMPROVEMENT BY VEGETATION MANAGEMENT1

ABSTRACT: Vegetation management aimed at increasing the amount of usable water yield from precipitation falling on upstream watersheds may be one alternative for supplementing water supplies. Indications are that water yields can be increased within a multiple-use framework, which can benefit or at least be compatible with other natural resource objectives. Through changes in vegetation on a watershed, it is possible to reduce evaporation losses only slightly but significantly increase streamflow runoff. In an assessment of potentials for water yield improvement in Arizona, experimental studies on various vegetation zones are reviewed. Because of either limited acreage or limited rainfall, the alpine, grassland, aspen, and desert shrub vegetation zones are not realistic management areas for Arizona. Furthermore, manipulation of pinyon-juniper woodlands does not appear promising at this time. Conversion of chaparral to grasses and forbs does appear to be a possible treatment for water yield improvement, as well as various silvicultural treatments of mixed conifer and ponderosa pine forests. Streamflow increases are given for experiments in chaparral, mixed conifer, and ponderosa pine vegetation zones. However, complete information on possible constraints for these zones is not currently available. Specific assessment of water yield management options for riparian vegetation is difficult to make, due to incomplete knowledge of water yield changes and other constraints for this vegetation zone. Prior to the final adoption of management practices, results of experimental work must be coupled with economic and social considerations.     

Forests and competing land uses in Kenya

Indigenous forests in Kenya, as in other developing countries, are under heavy pressure from competing agricultural land uses and from unsustainable cutting. The problem in Kenya is compounded by high population growth rates and an agriculturally based economy, which, even with efforts to control birth rates and industrialize, will persist into the next century. Both ecological and economic consequences of these pressures need to be considered in land-use decision making for land and forest management to be effective. This paper presents one way to combine ecological and economic considerations. The status of principal forest areas in Kenya is summarized and competing land uses compared on the basis of ecological functions and economic analysis. Replacement uses do not match the ecological functions of forest, although established stands of tree crops (forest plantations, fuel wood, tea) can have roughly comparable effects on soil and water resources. Indigenous forests have high, although difficult to estimate, economic benefits from tourism and protection of downstream agricultural productivity. Economic returns from competing land uses range widely, with tea having the highest and fuel wood plantations having returns comparable to some annual crops and dairying. Consideration of ecological and economic factors together suggests some trade-offs for improving land allocation decisions and several management opportunities for increasing benefits or reducing costs from particular land uses. The evaluation also suggests a general strategy for forest land management in Kenya.The views and interpretations expressed in this article are those of the authors and should not be attributed to the World Bank, its affiliated organizations, or any individual acting on their behalf.     

TRANSPORT OF ROAD-SURFACE SEDIMENT THROUGH EPHEMERAL STREAM CHANNELS1

ABSTRACT: Since the majority of road drainage points in western Washington and Oregon enter small, often ephemeral streams rather than large, fish-bearing waters, impact of road-surface sediment on biota in permanent streams depends, to a large extent, on transport through these small watercourses. A series of experimental additions of road-surface sediment was made to two ephemeral streams to examine the downstream transport of this material as a function of discharge and channel characteristics. These small streams were found to store large amounts of sediment washed from road surface. In no instance did either stream transport more than 45 percent of the added material to their mouths, distances of 95 and 125 m. Larger-sized sediment particles were delivered at a lower rate than finer material. Added sediment <0.063 mm in size was transported efficiently through the systems at all but the lowest flows tested. Material between 0.5 and 0.063 mm and from 2.0 to 0.5 mm in size were retained at progressively higher rates, with sediment in the coarser size category never exceeding a delivery of 10 percent of the added material. There were significant differences in the transport of sediment in the two larger size categories between the two streams. These differences were due to a much greater amount of woody debris in the stream with the lower delivery rates, which acted to trap and hold sediment, as well as a slightly longer and less steep channel.     

ECOSYSTEM MANAGEMENT AND THE CONSERVATION OF AQUATIC BIODWERSITY AND ECOLOGICAL INTEGRITY1

ABSTRACT: Ecologically effective ecosystem management will require the development of a robust logic, rationale, and framework for addressing the inherent limitations of scientific understanding. It must incorporate a strategy for avoiding irreversible or large-scale environmental mistakes that arise from social and political forces that tend to promote fragmented, uncritical, short-sighted, inflexible, and overly optimistic assessments of resource status, management capabilities, and the consequences of decisions and policies. Aquatic resources are vulnerable to the effects of human activities catchment-wide, and many of the landscape changes humans routinely induce cause irreversible damage (e.g., some species introductions, extinctions of ecotypes and species) or give rise to cumulative, long-term, large-scale biological and cultural consequences (e.g., accelerated erosion and sedimentation, deforestation, toxic contamination of sediments). In aquatic ecosystems, biotic impoverishment and environmental disruption caused by past management and natural events profoundly constrain the ability of future management to maintain biodiversity and restore historical ecosystem functions and values. To provide for rational, adaptive progress in ecosystem management and to reduce the risk of irreversible and unanticipated consequences, managers and scientists must identify catchments and aquatic networks where ecological integrity has been least damaged by prior management, and jointly develop means to ensure their protection as reservoirs of natural biodiversity, keystones for regional restoration, management models, monitoring benchmarks, and resources for ecological research.     

Ultrasound enhanced heterogeneous activation of peroxydisulfate by bimetallic Fe-Co/GAC catalyst for the degradation of Acid Orange 7 in water

Bimetallic Fe-Co/GAC （granular activated carbon） was prepared and used as heterogeneous catalyst in the ultrasound enhanced heterogeneous activation of peroxydisulfate （PS, S2O8 2-） process. The effect of initial pH, PS concentration, catalyst addition and stirring rate on the decolorization of Acid Orange 7 （AO7） was investigated. The results showed that the decolorization efficiency increased with an increase in PS concentration from 0.3 to 0.5 g/L and an increase in catalyst amount from 0.5 to 0.8 g/L. But further increase in PS concentration and catalyst addition would result in an unpronounced increase in decolorization efficiency. In the range of 300 to 900 r/min, stirring rate had little effect on AO7 decolorization. The catalyst stability was evaluated by measuring decolorization efficiency for four successive cycles.     

Study of the effects of bisphenol A using human fetal lung fibroblasts

正Bisphenol A(BPA,2,2-bis(4-hydroxyphenyl)propane;CAS#80-05-7)is a highly produced industrial chemical,with an estimated four billion kilograms produced worldwide each year(reviewed in Vandenberg et al.,2010).BPA serves as a monomer in the manufacture of polycarbonate,a hard,clear plastic.Polycarbonate plastics are used in many consumer products,such as reusable water bottles.BPA is also widely used to make epoxy resins,which are used as coating on the inside of some     

Leaching of aluminium from cookwares -- a review

Concern over the possible relation between environmental aluminium exposure and Alzheimer's disease has prompted studies of all forms of human intake of this element including that from foods. Aluminium cookware, apart from other sources of dietary aluminium, is considered to be a potential source of this metal to human beings. Various research groups have carried out aluminium leaching experiments with food, beverages and water under different experimental conditions modified by varying the level of pH, chloride, fluoride, citrate, acetate etc. The results reported by different workers show marked discrepancies in levels of leached aluminum. The apparent reason for such discrepancy in levels of aluminum leached can be attributed to factors such as non-systematic and non-uniform experimental designs, non-standard conditions maintained during the experiments and choice of method for aluminium analysis. In order to assess accurately the contribution of aluminium ingestion by human beings through aluminium cookware, the present review emphasises the need of i) standard size aluminium plates obtained from the same lot for one set of experimentations; ii) real life cooking conditions to highlight the role of various complexing species present in food e.g. citrate, oxalate, acetate, tartrate etc.; iii) role of chemistry of aluminium in presence of acidic, basic and neutral cooking medium and iv) strict analytical control in the estimation of aluminium. Results of a systematic study by the authors conducted on the abovementioned lines are also described.     

Demographic Responses by Birds to Forest Fragmentation

Abstract:  Despite intensive recent research on the effects of habitat loss and fragmentation on bird populations, our understanding of underlying demographic causes of population declines is limited. We reviewed avian demography in relation to habitat fragmentation. Then, through a meta-analysis, we compared specific demographic responses by forest birds to habitat fragmentation, providing a general perspective of factors that make some species and populations more vulnerable to fragmentation than others. We obtained data from the scientific literature on dispersal, survival, fecundity, and nesting success of birds. Birds were divided into subgroups on the basis of region, nest site, biogeographical history, and migration strategy. Species most sensitive to fragmentation were ground- or open-nesters nesting in shrubs or trees. Residents were equally sensitive to fragmentation in the Nearctic and Palearctic regions, but Nearctic migrants were more sensitive than Palearctic migrants. Old World species were less sensitive than New World species, which was predicted based on the history of forest fragmentation on these two continents. Pairing success was the variable most associated with fragmentation, suggesting an important role of dispersal. Fledgling number or condition, timing of nesting, and clutch size were not associated with sensitivity to fragmentation, suggesting that negative fragmentation effects on birds do not generally result from diminished food resources with increasing level of fragmentation. Future studies on demographic responses of birds to habitat fragmentation would be more effective if based on a combination of measures that can distinguish among the demographic mechanisms underlying population changes related to habitat fragmentation.