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11.
Becker  E. W.  Bier  W.  Ehrfeld  W.  Schubert  K.  Schütte  R.  Seidel  D. 《Die Naturwissenschaften》1976,63(9):407-411
The Science of Nature - The development of reliable manufacturing methods for commercial separation elements, the successful operation of separative stages, and extensive tests performed on plant...  相似文献   
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The soil fauna of ecofarmed and conventionally farmed fields and grasslands was investigated in various regions of Austria. The results obtained from the evaluation of a total of 13 paired sites are reviewed in this contribution: (1) many of the investigated soil zoological parameters do not differ statistically in ecofarmed and conventionally farmed fields and grasslands; (2) there are no striking differences in species composition and dominance structure of the protozoa, an important group of indicator organisms due to their delicate external membranes, their short generation time and their high contribution to energy flow and nutrient cycling; (3) all differences which can be guaranteed with an error probability of α = 10% or less invariably show higher biological activity in the ecofarmed plots. The soil physical and chemical investigations which accompanied the zoological studies on some sites indicate that the higher biological activity is caused by the higher humus content and the lower soil compaction. The organic matter content is significantly higher in the ecofarmed plots, whereas soil compaction is more pronounced under conventional cultivation; (4) conventional agriculture has a more detrimental effect on soil fauna in semi-arid regions without stockfarming than in atlantic regions with mixed husbandry. A short review of the literature shows our results to be consistent with those of other studies. It is increasingly evident that generalizations like ‘Conventional farming destroys life in the soil’ or ‘Ecofarming stimulates soil life’ are only partially supported by the available data. A far more comprehensive view taking into account especially climate, soil type and farm management is necessary. However, the discernible detrimental effects on the soil organisms caused by conventional farming call for serious consideration and ought to stimulate the development of soft agricultural technology and intensified soil biological research. Future research should include studies on productivity of soil animals under various management systems, the analysis of single factors (e.g. the special admixtures used in biodynamic farming) to elucidate causative mechanisms, and studies on the relationship between soil animals, crop production and sustained yield.  相似文献   
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The radiation budget of planets substantially determines their climates. For the terrestrial planets having their own imperceptible heat source compared to the solar radiation, the radiation budget supplies energy that can be transformed and used in their atmospheres and at their surfaces. The crucial role of the radiation budget for the Earth's climate is manifested in current international programs like the World Climate and Global Change Programs. The intercomparison and analysis of the radiation budget of the terrestrial planets, due to quite different atmospheric compositions and external conditions, provide a deeper insight into the relations of the different components of the radiation budget.  相似文献   
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