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Milan Straškraba 《Ecological modelling》1983,18(2):85-97
Hierarchical control formulations are given for a simple predator-prey model: self-optimization of one subsystem, natural multi-goal optimization, man's multiparameter control of an ecosystem and man's control of a self-optimizing ecosystem. Natural multigoal optimization suggests how several levels of an ecosystem can be optimized simultaneously. The idea of management of a self-optimizing ecosystem takes into account the reactions of the ecosystem to man's activity. 相似文献
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M. Straškraba 《Ecological modelling》1984,23(3):265-267
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Milan Straškraba 《Ecological modelling》1979,6(4):305-321
Based on cybernetic categories of natural control mechanisms, four generations of ecosystem models are distinguished: feed-forward, feedback, self-adaptation and self-organization models. The analysis of the natural control mechanisms in aquatic ecosystems suggests that different processes are controlled in different ways, and, although the four mechanisms were identified in historical sequence, they all operate simultaneously. The concept of self-organization of an ecosystem is introduced and specified for a model of an aquatic pelagic ecosystem. The concept of the ecosystem as a multilayer, multigoal and multiechelon hierarchical system with hierarchy of the levels of biological organization is also introduced. 相似文献
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Degradation of the pharmaceutical metronidazole via UV, Fenton and photo-Fenton processes 总被引:12,自引:0,他引:12
Degradation rates and removal efficiencies of Metronidazole using UV, UV/H2O2, H2O2/Fe2+, and UV/H2O2/Fe2+ were studied in de-ionized water. The four different oxidation processes were compared for the removal kinetics of the antimicrobial pharmaceutical Metronidazole. It was found that the degradation of Metronidazole by UV and UV/H2O2 exhibited pseudo-first order reaction kinetics. By applying H2O2/Fe2+, and UV/H2O2/Fe2+ the degradation kinetics followed a second order behavior. The quantum yields for direct photolysis, measured at 254 nm and 200-400 nm, were 0.0033 and 0.0080 mol E(-1), respectively. Increasing the concentrations of hydrogen peroxide promoted the oxidation rate by UV/ H2O2. Adding more ferrous ions enhanced the oxidation rate for the H2O2/Fe2+ and UV/H2O2/Fe2+ processes. The major advantages and disadvantages of each process and the complexity of comparing the various advanced oxidation processes on an equal basis are discussed. 相似文献
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Petrash Daniel A. Novák Martin Bohdálková Leona Krachler Micheal Čuřík Jan Veselovský František Štěpánová Markéta Umbría-Salinas Karelys Přechová Eva Komárek Arnost 《Environmental science and pollution research international》2021,28(13):16107-16121
Environmental Science and Pollution Research - Arsenic (As) concentrations and deposition fluxes were measured in snow and rime at 10 mountain-top sites near the borders between the Czech Republic... 相似文献