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701.
James O. Peterson Stephen M. Born Russel C. Dunst 《Journal of the American Water Resources Association》1974,10(6):1228-1245
ABSTRACT: The degradation of many lakes is the result of aging processes which have been accelerated by the activities of man. Where it is too late to prevent sedimentation and eutrophication problems, lake rehabilitation and protection comprise a resource management option warranting serious consideration. A Wisconsin Lake Renewal Demonstration Project has been evaluating several rehabilitation schemes for the past five years. A selected summary of Project lake rehabilitation activities, including nutrient inactivation, dilution, aeration, and several types of aquatic plant management, suggests the present status of lake rehabilitation. 相似文献
702.
Spencer A. Peterson David P. Larsen Steven G. Paulsen N. Scott Urquhart 《Environmental management》1998,22(5):789-801
N = 11,076). Results were compared to a large, nonrandomly sampled data set for the same area compiled by Rohm and others and
contrasted with lake trophic state information published in the National Water Quality Inventory: 1994 Report to Congress
[305(b) report. Lakes across the entire Northeast were identified by EMAP data as 37.9% (±8.4%) oligotrophic, 40.1% (±9.7%)
mesotrophic, 12.6% (±7.9%) eutrophic, and 9.3% (±6.3%) hypereutrophic. Lakes in the ADI and NEU generally are at a low, nearly
identical trophic state (96% oligotrophic/mesotrophic), while those in the CLP are much richer (45% eutrophic). EMAP results
are similar to results of the Rohm data set across the entire region. In the CLP, however, EMAP identified approximately 45%
of the lakes as eutrophic/hypereutrophic, while the Rohm data set identified only 21% in these categories. Across the entire
Northeast, the 305(b) report identified a much higher proportion (32.2%) of lakes in eutrophic condition and a much smaller
proportion (19.8%) in oligotrophic condition than did the EMAP survey data (12.5% ± 7.9% and 37.9% ± 8.5%, respectively).
Probability sampling has several advantages over nonrandom sampling when regional resource condition assessment is the goal. 相似文献
703.
Karl J. C. Harries 《Natural resources forum》1998,22(1):1-13
At common law, the legal nature of a mining royalty between private parties will decide the respective rights of payor and recipient. In some circumstances, it will also determine whether the interest of the recipient will prevail or may be lost and ignored. Industry practices, even those of long standing, that are contrary to the law will not change the law or its effect to meet such concerns. This paper looks at the development of the mining royalty between private parties in Canada and the effect of the realization by recipients that contractual royalties, as opposed to royalties that are interests in the lands or product to which they relate, can be lost in certain circumstances. Suggestions are made for some features that may assist in transforming an otherwise contractual royalty into a real property interest. Some of the concerns for both payor and recipient with respect to the implementation of such suggestions are also discussed.
The article has two appendices attached. Appendix A is an extract from an article by the author discussing the concept of payment of a royalty in kind which is relevant to such suggestions. Appendix B contains some of the more lengthy explanatory notes referred to in the text of the article. 相似文献
The article has two appendices attached. Appendix A is an extract from an article by the author discussing the concept of payment of a royalty in kind which is relevant to such suggestions. Appendix B contains some of the more lengthy explanatory notes referred to in the text of the article. 相似文献
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709.
DNA-dependent RNA polymerases of archaebacteria are distinct from those of eubacteria both in structure and in function. They show similarities to those of the eukaryotic cytoplasm. Extremely thermophilic anaerobic sulfur-respiring archaebacteria isolated from solfataric waters represent four different families, the Thermoproteaceae, the “stiff filaments”, the Desulfurococcaceae and the Thermococcaceae, of a novel order, Thermoproteales. Together with the Sulfolobales, they form the second branch of the urkingdom of the archaebacteria besides that of the methanogens and extreme halophiles. Thermoplasma appears isolated. 相似文献
710.