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701.
Relative to manufacturing, service activities are often considered by planners and officials to generate considerably less environmental pollution. This hypothesis is tested by means of an examination of the economic linkages of both manufacturing and service activities and of the resulting direct and indirect emissions of five air pollutants per dollar of output in the California statewide air basin and in four regional basins within the state. Overall acceptance or rejection of the hypothesis depends in part on the particular pollutant and air basin considered but, most importantly, on the judgement as to what activities are to be considered as service activities.This paper is based on research sponsored by the California Air Resources Board under Agreement A7-143-30.  相似文献   
702.
ABSTRACT: The period of time from identification of a possibly desirable inland waterway transportation project to its actual implementation has been observed to be inordinately long. It is Hypothesized that at Least one cause of delays in project approval and implementation is a analytical credibility associated with project feasibility analysis conducted by the U.S. Army Corps of Engineers. This paper examines this hypothesis in terms of the proposal to construct a new, expanded lock at the Bonneville Dam on the Columbia River. The principle finding is that the analysis conducted by the Corps is conceptually flawed, methodologically questionable, internally inconsistant, and inappropriately narrow in scope.  相似文献   
703.
The Indian energy scene has undergone a distinct change during the last three decades. In overall terms the reliance on traditional (non-commercial) forms of energy has declined gradually and the share of modern commercial forms of energy has steadily increased. The preference towards commercial forms of energy has resulted in rapid growth of demand, and the growth rate of commercial energy consumption has outpaced the overall growth of the economy. While India has been able to manage oil supplies without much difficulty through indigenous production and imports, there have been balance of payments problems due to the steep increase in the import bill. An overall energy strategy has been formulated for the Sixth Five-Year Plan which will ensure adequate supplies of energy to meet short-term energy requirements while keeping in view the long-term perspective. The plan envisages achieving a balance between energy supplies and demand in the short and medium term by accelerating exploitation of domestic conventional energy resources and managing demand through appropriate measures. In the long term, exploitation of new and renewable energy resources is the basis of energy development strategy. La situation énergétique en Inde a subi une transformation distincte durant ces trois dernières décennies. En termes généraux, la dépendance vis-à-vis des formes traditionnelles d'énergie (non-commerciales) a diminué graduellement et les formes commerciales modernes d'énergie se sont accrues d'une manière constante. La préférence pour les formes commerciales d'énergie a eu pour résultat l'accroissement rapide de la demande et le taux de croissance de la consommation énergétique commerciale a surpassé la croissance totale de l'économie. Alors que I Inde a été capable de s'approvisionner en pétrole sans trop de difficulté par des moyens de production indigéne et d'importations, des problèmes de balance de paiements sont survenus à cause de l'augmentation aiguë de la facture énergétique. Une stratégie globale en matière d'énergie a été formulée pour inclusion dans le sixième plan quinquennal, ce qui assurera des approvisionnements en energie adéquats pour faire face aux exigences énergétiques à court terme tout en gardant en vue les objectifs à long terme. Le plan envisage d'atteindre un équilibre entre l'offre et la demande en matière d'énergie à court et moyen termes en accélérant l'exploitation des ressources énergétiques conventionnelles du pays et en contrölant la demande par des mesures appropriées. A long terme, la base de la stratégie du développement en matière d'énergie consiste en l'exploitation des ressources énergétiques nouvelles et renouvelables. La escena energética de la India a sufrido un cambio marcado durante las últimas tres décadas. En general la dependencia en la energia no comercial a declinado gradualmente mientras que el uso de recursos de energia comercial ha aumentado continuamente. Esto ha generado una rápida tasa de creamiento de la demanda de energia comercial que supera la tasa de crecimiento económico. A pesar de que la India pudo satisfacer sus necesidades de petróleo mediante producción propia e importaciones hay problemas en la balanza de pagos. Se ha formulado estrategia general para el Sexto Plan Quinquenal que asegurará el suministro en el corto plazo sin descuidar la perspectiva a largo plazo. El plan prevee obtener el balance de la oferta y la demanda en el corto y mediano plazo mediante una exploración acelerada y una apropiada administración de la demanda. Para el largo plazo, la explotación de recursos nuevos y renovables de energia es la base de la estrategia de desarrollo energético.  相似文献   
704.
ABSTRACT: Gaged watersheds can provide information as to geomorphic, and geologic influence on the spatial variability of rainfall-runoff relationships. However, correlations between raingages distributed throughout the basin, and stream discharge are influenced by both storm patterns and drainage basin characteristics. Factor analysis has been applied to rainfall-runoff relationship to isolate the storm pattern from a basin response factor. Comparing two periods of time separated by eight years reveals relative stability in the rainfall attenuation (basin response) factor, while storm patterns for the two periods of record are quite disparate.  相似文献   
705.
ABSTRACT: The cost of sanitary facilities is a major cost item in recreation areas at water resources projects. Often planners wish to analyze the tradeoffs in providing different levels of service at these areas. Cost functions are presented in this paper to enable the planner to make quick comparisons between different types of buildings, sizes, exterior treatments, and number of fixtures.  相似文献   
706.
Paired water samples were simultaneously activated from two different vertical positions within the approach section of a flow-control structure to determine the effect of sample intake position on nonpoint runoff parameter concentrations and subsequent event loads. Suspended solids (SS), total phosphorus (TP) and organic plus exchangeable nitrogen [(Or+Ex)-N] were consistently higher throughout each runoff event when sampled from the floor of the approach section as opposed to those samples taken at midstage. Dissolved molybdate reactive phosphorus (DMRP) and ammonium (NH4-N) concentrations did not appear to be significantly affected by the vertical difference in intake position. However, the nitrate plus nitrite nitrogen [(NO3+NO2)-N] concentrations were much higher when sampled from the midstage position.Although the concentration differences between the two methods were not appreciable, when evaluated in terms of event loads, discrepancies were evident for all parameters. Midstage sampling produced event loads for SS, TP, (Or + Ex)–N, DMRP, NH4-N, and (NO3+NO2)-N that were 44,39,35,80,71, and 181%, respectively, of floor sampling loads. Differences in loads between the two methods are attributed to the midstage position, sampling less of the bed load. The correct position will depend on the objective; however, such differences should be recognized during the design phase of the monitoring program.This work was supported by the Soil Science Department, College of Agriculture and Life Sciences, University of Wisconsin-Madison, and by the U.S. Environmental Protection Agency, Region V., Chicago, Illinois (Grant No. G005139-01).  相似文献   
707.
A mathematical model simulates the cumulative volume of debris produced from brushland watersheds. Application of this model to a 176-km2 (0.678 = mi2) watershed along the southern flank of the Central San Gabriel Mountains permits assessment of expected debris production associated with alternative fire-management policies. The political implications of simulated debris production are evaluated through a conceptual model that links interest groups to particular successional stages in brushland watersheds by means of the resources claimed by each group. It is concluded that in theory, a rotation burn policy would provide benefits to more interest groups concerned about southern California's brushland watersheds than does the current fire exclusion policy.This research was supported by the College of Agriculture and Life Sciences, University of Wisconsin-Madison, and by the Office of Water Research and Technology, USDI, under the Allotment program of Public Law 88–379, as amended, and by the University of California. Water Resources Center, as a part of Office of Water Research and Technology Project No. A-058-CAL and Water Resources Center Project UCAL-WRC-499. Support was also provided by the California Agricultural Experiment Station, Berkeley, California.  相似文献   
708.
Technetium-99 (99Tc) is formed in significant amounts (6.2% fission yield) during fission in both nuclear reactors and nuclear bombs. The effects of technetium on soybeans (Glycine max) were studied in relation to (a) cytochemical events in the apical meristems of germinating seedlings; (b) growth responses to 0, 0.04, 0.2, 1.0, 5.0, and 20.0 ppm Tc; (c) growth responses to varying levels of Tc after a prior 5-day germination on Tc-free media, and (d) response to Tc in the presence of added manganese.By 20 days, reductions in growth were evident at all levels of Tc except 0.04 ppm (Experiment 2). Root growth was most severely affected, and seedling abnormality at 20 ppm was fivefold greater than that of the controls. The effect of 20 ppm Tc was evident at 10 days when the accumulated absorption dose was approximately 25 rads. The first evidence of damage at this dose was a delay in the initiation of the first trifoliate leaf. The shoot meristem size was 1.2-fold smaller than that of the control; however, there was no cytological evidence of radiation-induced damage. Observation of mitotic figures did not reveal any chromosome aberrations, micronuclei, or chromosome bridges. The lowest level of Tc showing toxicity was 0.2 ppm which resulted in a 31% reduction in growth at 20 days. The accumulated dose was 0.5 rad (0.025 rad/day) and thus it seems unlikely that the rapid inhibition of growth and development is due to radiological toxicity. It is quite probable that the growth effects are due to chemical toxicity possibly due to nutrient competition and/or substitution in uptake or metabolism. However, extremely low doses of radiation have been shown to delay the onset of DNA synthesis (possibly by membrane effects) inTradescantia and until the actual mechanism of Tc inhibition is determined a radiation effect cannot be totally ruled out.This research was partially supported by ERDA Contract EY-76-S-02-4139  相似文献   
709.
ABSTRACT: Sediments were investigated from two Florida lakes that have not been infested with the submersed, perennial, noxious plant Hydrilla verticillata. Aqueous extracts of the peat-like sediments from these lakes were shown to inhibit the growth of Hydrilla verticillata in laboratory systems. The extracts have substantial concentrations of organic carbon and iron. The apparent molecular weight of the inhibitory fraction is between 2,000 and 10,000, based upon ultrafiltration studies. Hydrilla growth was about 35 percent relative to control for a partially purified fraction at a level of 0.4 ppm organic carbon. Growth was measured as change in biomass (wet and dry) over a one-week period. The inhibitory material was highly fluorescent, dark brown, and inhibitory activity was lost after passage over an anion-exchange column (Cellex-D).  相似文献   
710.
ABSTRACT: Indices of annual diameter growth of trees were used to reconstruct drought in southern California back to A.D. 1700. A regional Palmer Drought Index served as predictand and tree-ring indices from eight sites as predictors in multiple linear regression analyses that yielded the prediction (reconstruction) equations. The regression explained 69 percent of the variance in Palmer Index in the period of calibration. The long-term reconstruction indicated that drought was rare in the first half of the current century relative to other discrete 50-year periods, and that based on evidence to date the last half of the 20th century may well turn out to be the most drought prone since A.D. 1700 in southern California.  相似文献   
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