Watershed development in India. 1. Biophysical and societal impacts

This paper recommends a revision of watershed development policy in India in relation to the planning of development interventions involving agricultural intensification and rainwater harvesting following biophysical and societal impact studies carried out on two watershed development projects in Karnataka. A need for changes in policy has arisen in response to progressive catchments closure at the basin level and declining volumes of water flowing into village level reservoirs (known locally as tanks). Flow reductions have occurred largely as a result of increased agricultural intensification over the past 10–15 years. Field levelling, field bund construction, soil water conservation measures, farm ponds, the increase in areas under horticulture and forestry and the increased abstraction and use of groundwater for irrigation are all contributing factors to reduced flows. Planning methodologies and approaches, which may have been appropriate 20 years ago for planning water harvesting within watershed development projects, are no longer appropriate today. New planning approaches are required which (1) take account of these changed flow conditions and (2) are also able to take account of externalities, which occur when actions of some affect the livelihoods of others who have no control or influence over such activities and which (3) contribute to the maintenance of agreed minimum downstream flows for environmental and other purposes.

Radioactive contamination from medical uses and recent regulatory activity in the U.S.A.

Recent publications relating to environmental radioactive contamination from medical uses are described. It appears that the unprecented growth of medical uses of radionuclide continues in the United States; hospital effluents are not a measurement problem; and the regulatory climate is uncertain. The major need, appears to be in the reduction or control of medical radiation exposure to the patient from diagnosis and therapy.     

Intra- and Interpopulation Variation of Leaf Life Span in Rhododendronledebourii Pojark. and Rh. dauricum L. (Ericaceae Juss.) and Its Environmental Determination

Russian Journal of Ecology - Twenty cenopopulations of Rhododendron dauricum and Rh. ledebourii, two closely related and morphologically hardly distinguishable species, have been studied with...     

G.V. Shlyakhtin,E.V. Zav'yalova,and V.G. Tabachishin,Ptitsy Saratova i ego okrestnostei: Sostav,okhrana i ekologicheskoe znachenie(Birds of Saratov and Its Vicinity: Composition,Protection, and Ecological Significance), Saratov: Saratov. Gos. Univ., 1999

Russian Journal of Ecology -     

Seasonal Distribution of Chemical Elements in Alisma plantago-aquaticaL. and Sagittaria sagittifoliaL.

Russian Journal of Ecology -     

Longer-duration uses of tetracyclines and penicillins in U.S. food-producing animals: Indications and microbiologic effects

We review and analyze regulatory categories for longer duration of use (defined as ≥ 7 day) tetracyclines (TCs) and penicillins (PNs) approved for U.S. livestock and poultry, together with scientific studies, surveillance programs and risk assessments pertaining to antimicrobial resistance. Indications listed on a government database were grouped into three broad categories according to the terminology used to describe their use: disease control (C), treatment (T) and growth improvement (G). Consistent with mostly therapeutic uses, the majority (86%) of listed indications had C and/or T terms. Several studies showed interruption of early disease stages in animals and modulation of intestinal microflora. Longer-duration exposures are consistent with bacteriostatic modes of action, where adequate exposure time as well as concentration is needed for sufficient antimicrobial activity. Other effects identified included reduced animal pathogen prevalence, toxin formation, inflammation, environmental impacts, improved animal health, reproductive measures, nutrient utilization, and others. Several animal studies have shown a limited, dose-proportionate, selective increase in resistance prevalence among commensal animal bacteria following longer-duration exposures. Pathogen surveillance programs showed overall stable or declining resistance trends among sentinel bacteria. Quantitative, microbiologically detailed resistance risk assessments indicate small probabilities of human treatment failure due to resistance under current conditions. Evaluations of longer-duration uses of TCs, PNs, and other antimicrobial classes used in food-producing animals should consider mechanisms of activity, known individual- and population-level health and waste reduction effects in addition to resistance risks.     

Is Bat Distribution Dependent on Relief? (A Reply to the Paper by V.Yu. Il'in and D.G. Smirnov)

The data on bat distribution published by Il'in and Smirnov (2000) were reanalyzed in order to test the hypothesis concerning the connection between species occurrence and forms of relief. The pattern revealed by statistical analysis disagrees with the conclusions drawn by these authors; furthermore, because of an obvious sampling bias, the data published by Il'in and Smirnov are hardly suitable for rigorously testing their hypothesis.     

The Northwest U.S. Dam Breaching Decision: Factors, Costs and Benefits

Northwestern United States' salmon populations have fallen precipitously. Attempts at salmon restoration are going on and dam breaching is being considered. Costs associated with the continued restoration attempts including hatchery stocking, barging and trucking salmon around the dams are high while benefits are unclear. Those costs may be greater than dam breaching. An additional impetus for dam removal is the revival of the commercial salmon fishing industry. This may not occur for both ecological and economic reasons. Ecologically complete restoration may not be feasible. Economically, the rise of competitively priced salmon aquaculture will reduce the value of any future commercial catch. A statistical relationship between falling prices for wild salmon and rising salmon aquaculture output is shown.