Results 271 to 280 of about 352,390 (308)
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The ecological status of bracken
Botanical Journal of the Linnean Society, 1976Information about the morphology of bracken (Pteridium aquilinum (L.) Kuhn var. aquilinum) and the chief nutrients in the frond at different times of the year introduce an account of litter production and its accumulation in relation to the behaviour of frond, root and rhizome systems.
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An EPA program for monitoring ecological status and trends
Environmental Monitoring and Assessment, 1991Despite hundreds of millions of dollars spent annually in the United States on environmental monitoring, policy and decision makers seldom have ready access to monitoring data to aid in prioritizing reasearch and assessment efforts or to assess the extent to which current policies are meeting the desired objectives. EPA is currently conducting research
J J, Messer +2 more
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The Status, Predicament and Countermeasures of Global Ecological Crisis
Advanced Materials Research, 2013With the rapid development of science and technology, human cognition towards the nature has obtained great progress. They have created abundant wealth and caused serious damage to nature as well. The extent of environmental pollution has never been serious than ever before.
Li Jiang, Xiang Lin He, Erkki Hiltunen
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Indicators of the Ecological Status of Agroecosystems
1992Agroecosystems can be viewed as production systems that provide food and fiber products essential for the health and well-being of humankind. This view is not incorrect, but it is incomplete. Agricultural commodities such as crops and livestock are one of several agroecosystem components (Fig. 35.1).
Julie R. Meyer +6 more
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The status and ecology of crocodiles in the Purari
1983In many areas, including the Purari River basin, the extensive hunting of crocodiles during the last three decades has drastically reduced their wild populations. The Government of Papua New Guinea has been aware of the pressures on wild crocodile populations and in the last five years, with the help of the United Nations has actively encouraged and ...
J. C. Pernetta, S. Burgin
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Sediment nutrients, ecological status and restoration of lakes
Water Research, 2019Phosphorus (P) is the main nutrient that causes eutrophication in fresh waters. The majority of P in lake ecosystems is usually stored in the bottom sediment, hence P cycling from the sediment into the water column can significantly and negatively impact water quality.
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Nutritional status in japan from the viewpoint of numerical ecology
Social Science & Medicine. Part A: Medical Psychology & Medical Sociology, 1978Abstract This study reports the internal structure of the Japanese dietary life on the basis of statistical analysis about the amount of consumption of major foods which are observed in households respectively. A new concept, “food consumption structure”, is introduced through the matrix of correlation coefficient among major foods.
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