Entrainment mortality of Ichthyoplankton: Detectability and precision of estimates

The ability to detect and to develop a precise and accurate estimate of the entrainment mortality fraction is an important step in projecting power plant impacts on future fish population levels. Recent work indicates that these mortailities may be considerably less than 100% for some fish species in the early life stages. Point estimates of the entrainment mortality fraction have been developed based on probabilistic arguments, but the precision of these estimates has not been studied beyond the simple statistical test of the null hypothesis that no entrainment mortaility exists.The ability to detect entrainment mortality is explored as a function of the sample sizes (numbers of organisms collected) at the intake and discharge sampling stations of a power plant and of the proportion of organisms found alive in the intake samples (intake survival). Minimum detectable entrainment mortality, confidence interval width, and type II error (probability of accepting the null hypothesis of no entrainment mortality when there is mortality) are considered. Increasing sample size and/or decreasing sampling mortality will decrease the minimum detectable entrainment mortality, confidence interval width, and type II error for a given level of type I error.The results of this study are considered in the context of designing useful monitoring programs for determining the entrainment mortality fraction. Preliminary estimates of intake survival and the entrainment mortality fraction can be used to obtain estimates of the sample size needed for a specified level of confidence interval width or type II error. Final estimates of the intake survival and the entrainment mortality fraction can be used to determine the minimum detectable entrainment mortality and the type II error.     

AN EXAMINATION OF LAND USE - NUTRIENT EXPORT RELATIONSHIPS1

ABSTRACT: Lake and watershed management strategies and recent environmental legislation dictate that nonpoht nutrient sources associated with storm water runoff must be assessed. Accordingly, a nutrient flu assessment for phosphorus and nitrogen is conducted through an extensive literature review of nutrient export studies. These studies are reevaluated. The nutrient export coefficients are screened according to sampling design criteria and compiled according to land use. The ecological mechanisms within each land use influencing the magnitude of nutrient flux are also discussed     

ESTIMATION OF PRE- AND POST-DEVELOPMENT NONPOINT WATER QUALITY LOADINGS1

ABSTRACT: A simple procedure for estimating pre- and post-development water quality loadings from residential communities is discussed. The procedure deals with: (a) gathering basic water quality loading numbers observed by others at several watersheds with various land uses; (b) obtaining the breakdown of proposed land uses at various phases of the community development; and (c) estimating pre- and post-development water quality loading numbers by taking the weighted average of the basic loading numbers in terms of areal coverages of different land uses at various phases of development. Results of this simplified procedure have been verified indirectly by comparing them with the estimates derived independently through a more fundamental but time-consuming approach. The procedure was used to evaluate the anticipated water quality impact of two future residential communities in South Florida by analyzing four water quality parameters: Suspended Soils (SS), Total Nitrogen (TN), Total Phosphorus (TP), and Biochemical Oxygen Demand (BOD₅). Although computation of loading numbers with mixed land uses is not an exact science at the present time, the recommended approach appears to be the best available technique to analyze quantitatively the water quality-quantity-land use interactions.     

ON THE MEASUREMENT OF ENVIRONMENTAL IMPACTS OF PUBLIC PROJECTS FROM A SOCIOLOGICAL PERSPECTIVE1

ABSTRACT: The major objectives are (1) to identify the problems involved in measuring the environmental impacts of public projects from selected perspectives, and (2) to elaborate a sociological approach used in an empirical investigation in that respect. The construct of environmental impact of a planned action is generally operationalized from different perspectives and with different methodological emphases in the various disciplines. Even the term environment does not elicit agreement among users as to its exact meaning. Although there has been a steady increase in the number of studies from a sociological perspective concerning environmental problems, there is lack of sociological counsel in writing environmental impact statements. Overall, we lack sociological methodology and operational procedures for that purpose. In an attempt to bring some empirical focus to this field, attitudinal measures employed to discover how residents of a river basin perceived negative and positive environmental impacts of a proposed watershed development project are reviewed. These come from a study of creation of the Cooper Reservoir and Dam in Texas. Data on 343 heads of households m the selected areas were collected through structured questionnaires with items on personal information, a vested interest scale, a knowledge of the project scale, and an environmental impact scale. Data show that perception of impacts by residents is influenced significantly by degree of their vested interests involved. Variables for inclusion in a sociological model of environmental impact are suggested.     

Air quality assessment along Dhanbad - Jharia road

Road ambient air pollution status along Dhanbad – Jharia road isstudied and presented in this article. The selection of this areais made considering the importance of the road in Dhanbad district and the nature of activities taking place along the road, which reflect that the portion of road upto Dhansar can be considered as having commercial areas on both sides and that from Dhansar to Jharia as having industrial areas on both sides.For the assessment of the ambient air quality along the road monitoring is done at the following five locations: Indian Schoolof Mines (ISM), main gate; Bankmore; Dhansar police check post; Dhansar opencast project agent office and a residential house beside the Rajapur opencast project. The location of ISM, maingate is specially chosen as this represents a commercial shoppingcomplexes and the situation can be compared with that at Bankmore. Monitoring of ambient air quality is done following thestandard procedure prescribed in IS: 5182. In addition the concentration of lead, zinc, copper, iron, manganese, cadmium metals in SPM is also monitored. The ambient air quality is monitored in the months of September and November 1999, respectively, to represent monsoon and winter seasons. The SPM concentration observed at all the five locations in the winterseason is more than the permissible limits for commercial andindustrial areas. However, in the monsoon season, the SPM concentration is higher than the permissible limit at the twocommercial locations, i.e., ISM gate and Bankmore, while it isless than the prescribed limit for industrial areas at the remaining three locations. At the ISM gate and Bankmore the SPM generation is mainly by vehicular traffic while at other three locations it was in addition due to mining and other activities.     

CADMIUM ACCUMULATION AND TOXICITY IN SUBMERGED PLANT HYDRILLA VERTICILLATA (l.f.) ROYLE

Cadmium accumulation and its toxicity in relation tochlorophyll, protein, cysteine contents and in vivo nitrate reductaseactivity were studied under controlled conditions in Hydrillaverticillata, a submerged commonly occurring macrophyte. Plants weresubjected to six different concentrations of Cd ranging from 1.0 to 25.0 µM for 24, 48, 72 and 168 h. Tissue Cd concentration was maximum (13.71 µmoles/g dw) at 25 µM background concentration. At this concentration, a decrease of approximately 79 and 72% was found in chlorophyll and protein content. In vivo nitrate reductase activity was stimulated at 1.0 µM; however, the activity gradually declined beyond this concentration. Exposure to various cadmium concentrations resulted in an increase in cysteine content of the plant.     

Investigation of potentially toxic heavy metals in different organic wastes used to fertilize market garden crops

The benefits of using organic waste as fertilizer and soil amendment should be assessed together with the environmental impacts due to the possible presence of heavy metals (HMs). This study involved analysing major element and HM contents in raw and size-fractionated organic wastes (17 sewage sludges and composts) from developed and developing countries. The overall HM concentration pattern showed an asymmetric distribution due to the presence of some wastes with extremely high concentrations. HM concentrations were correlated with the size of cities or farms where the wastes had been produced, and HM were differentiated with respect to their origins (geogenic: Cr–Ni; anthropogenic agricultural and urban: Cu–Zn; anthropogenic urban: Cd–Pb). Size fractionation highlighted Cd, Cu, Zn and Pb accumulation in fine size fractions, while Cr and Ni were accumulated in the coarsest. HM associations with major elements revealed inorganic (Al, Fe, etc.) bearing phases for Cr and Ni, and sulfur or phosphorus species for Cd, Cu Pb and Zn.     

Spore inhibition-based enzyme substrate assay for monitoring of aflatoxin M1 in milk

A spore germination-based concept and its transformation into a field level prototype for monitoring aflatoxin M₁ (AFM₁) in milk was developed. Initially, 15 strains of Bacillus spp. procured from different culture collection were screened for AFM₁ sensitivity using spot assay and marker strain showing inhibition at 0.5 ppb was selected based upon maximum zone of inhibition. The selected strain B. megaterium 2949 was further screened for different enzymes activities and subsequently its spores were produced to an extent of 73.13% ± 3.197% in newly developed sporulation medium containing beef extract (0.0075% ± 0.0004%), yeast extract (0.015% ± 0.001%), peptone (0.0375% ± 0.0016%), and sodium chloride (0.0375% ± 0.0018%). A spore germination-based concept/ assay was optimized by immobilizing spores in eppendorf with pretreated milk (80°C/15 min) containing germinant and chromogenic substrate followed by incubation at 37°C. The appearance of sky blue color within real time of 45 min indicated spores germination and release of specific marker enzyme such as acetyl esterase and its specific action on chromogenic substrate which demonstrates absence of AFM₁ in milk. However, if there was no color change, presence of AFM₁ at 0.5 ppb MRL was denoted by Codex. The developed concept on AFM₁ detection was validated and a correlation of 0.97 was established with AOAC approved Charm 6602 and ELISA at Codex MRL with minimal false positive and negative results. The cost effective test has potential application in dairy farms, manufacturing, and R&D units for routine monitoring of AFM₁ in milk.