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971.
David R. Breininger Vickie L. Larson Brean W. Duncan Rebecca B. Smith Donna M. Oddy Michael F. Goodchild 《Conservation biology》1995,9(6):1442-1453
Remote sensing and geographical information systems are used to analyze landscapes important to species of conservation concern. The accuracy of the methods depends on how closely habitat mapping classes are linked to population demography. Habitat use by Florida Scrub Jays ( Aphelocoma c. coemlescens ) was quantified using circular plots. Habitat variation was mapped using high-resolution aerial photography on a site where all Florida Scrub Jays were color-banded. Nest site selection, nest success, yearling production, and breeder survival were measured within Florida Scrub Jay territories. Habitat use was lowest in areas without scrub oaks or areas within 136 m from forests. Open oak, dominated by scrub oaks and open sandy areas, had the highest use and nest success among habitats. Open oak occurred as narrow patches ( <20 m wide) in landscapes dominated by matrix habitat (palmetto-lyonia and swale marshes). Most wide patches (>50 m) of open oak were potential population sources, where reproduction exceeded mortality. Areas with patches of open oak of less than 1 ha were usually population sinks. Open oak occurred as less flammable patches in a landscape subject to frequent fires. Population sources varied temporally and spatially with fires and site potential to support scrub oaks (soils). Analyses of landscape patterns and dynamics indicated that habitat mapping should not only include patches of currently optimal habitat but should also include landscapes associated with open oak. The influences of landscape patterns on habitat use, reproductive success, survival, and territory size can be quantified at different scales starting with attributes associated with habitat patches, nest sites, and territories. Potential mapping errors occur, however, when habitats are used to quantify the areal extent of sources and sinks and similar population attributes important for species persistence. 相似文献
972.
Duane B. Oyen Jerald R. Barnard 《Journal of the American Water Resources Association》1975,11(3):483-490
ABSTRACT: This study examines agricultural land use change in the flood plain of the Iowa River as a result of building the Coralville Dam. Estimates of land use change and the benefits realized from the project are compared to the original project study benefits estimated by the Corps of Engineers. An analysis of the factors affecting land use change is carried out through a regression model to determine those variables that explain observed land use change. 相似文献
973.
974.
975.
The effects of predominant currents on the morphology of coral reefs has been studied in the leeward patch reefs of Anegada, British Virgin Islands. Measurements of current velocity and direction and sediment characteristics together with mapping of approximately 31 patch reefs within a 2 km2 area suggest that even under relatively low but constant current velocities (surface current 20 cm sec-1) the major reef-building corals show definite distribution patterns on the reef. The currents also appear to be responsible, in part, for marked orientation and elongation of patch reefs in a north-west/ south-east direction and for a gradation of patch-reef type across the study area. 相似文献
976.
Albin Brandstetter Roger L. Engel Dennis B. Cearlock 《Journal of the American Water Resources Association》1973,9(6):1188-1200
ABSTRACT: A comprehensive mathematical model (Urban Wastewater Management Model) has been developed to continuously simulate time-varying wastewater flows and qualities in complex metropolitan combined sewerage systems. The model serves three functions: (1) assessment of existing or planned system performance in relation to other wastewater discharges in either a metropolitan or river basin area; (2) determination of the optium operation or automatic control of existing or planned systems during rainstorms; and (3) determination of the most economically feasible combination of design alternatives for improving or expanding existing systems to meet specified performance criteria. The model provides an efficient engineering tool for evaluating and controlling pollutant discharges from combined sewerage systems (including treatment plants) to receiving waters, while considering the time and spacial variations of rainfall and dry-weather flows and qualities as well as economic constraints. 相似文献
977.
B. Fullerton Dr R. C. Wilkinson Jeremy Howells Naima Chabbis M. F. Downing 《Journal of Environmental Planning and Management》1986,29(2):98-100
URBANIZATION AND COMMUNITY BUILDING IN MODERN NORWAY
J. S. Tortenson, M. F. Metcalfe, T. F. Rasmussen
Urbana Press, Oslo 1985. 312 pp., figs and tables.
REGIONAL DEVELOPMENT POLICY
R. Riddell
Gower, 1985. £18.50
REVIEW OF SERVICE INDUSTRIES: A GEOGRAPHICAL APPRAISAL
P. W. Daniels
Methuen, 1985. £27.50.
ARABIC‐ISLAMIC CITIES: BUILDING AND PLANNING PRINCIPLES
Besim Selim Hakim
KPI Ltd., London, 1986. pp. 192. £46 (h/b)
FIFTY YEARS OF LANDSCAPE DESIGN
Sheila Harvey and Stephen Rettig
The Landscape Press, 1985. £12.50
CAPABILITY BROWN AND THE EIGHTEENTH CENTURY ENGLISH LANDSCAPE
Roger Turner
Weidenfeld & Nicholson. £16.95. 相似文献
978.
Dilution of indoor air contaminants with less contaminated outdoor air is the most common strategy for control of indoor air quality. Unfortunately this strategy frequently imposes a substantial energy burden. If the contaminants are associated with occupants and their activities, a ventilation control system based on the carbon dioxide level in the controlled space is shown to relieve this energy burden. A test was carried out in the Fridley, MN, Junior High School Music Department to obtain air quality, energy, and subjective response data on an Automatic Variable Ventilation System. A control system with both CO2 and temperature inputs was devised to control the use of outdoor air. Infiltration measurements lead to a quantitative measure of ventil3tion efficiency. This in turn led to recommendations for air circulation patterns in rooms. The measured ventilation efficiency enabled energy and CO2 models to fit measured data. Energy savings of approximately 20% were found for this application. Subjective response of the occupants also was measured. A special questionnaire, subjected to statistical analysis, showed that the subjects felt warmer with increased CO2 in the room air. 相似文献
979.
We have adapted a procedure which was developed for studying the correlations in the distribution of genetic factors, such as sex ratios in siblings, to obtain estimates of the correlation between the number of mutagens and the number of nonmutagens in a sample. Positive correlations with correlation coefficients in excess of 0.8 were obtained. The high correlation suggests that it is possible to estimate the number of mutagens in samples with N > 100 compounds as (0.064 ± 0.01) N. 相似文献
980.