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Eurasian Soil Science - The biomass of prokaryotes and fungi, organic carbon stocks, and CO2 emission were studied in the Cryosols and Leptosols of Franz Josef Land. The highest carbon stocks were...  相似文献   
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Eurasian Soil Science - Quantitative characteristics of microbial communities in southern agrochernozems of the Stavropol region managed with the use of no-till technology and moldboard plowing...  相似文献   
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The current status and prospects for the development of the Red Data Book of Russian Soils are discussed. It is argued that this book should become a part of a more general document encompassing not only soils but also other natural resources. The work on the Red Data Book of Natural Resources should include biological, soil, hydrological, geological, landscape, and noospheric objects, as all of them are tightly interrelated and have to be taken into account in the elaboration of the environmental conservation strategy. The noospheric direction implies the study and conservation of cultural objects in their integrity with the environment.  相似文献   
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The development of the Red Data Book of Eurasian Soils is a challenge necessitated by the intensive and exhaustive use of soil resources. The long-term strategy of interaction between humans and the environment should be directed towards the creation of favorable conditions for the development of society and saving of nature via application of new legislative norms aimed at preservation of pedodiversity and especially valuable soils. It is important to develop pedology as a fundamental science and to harmonize the relation-ships between humans and nature. The 30-year-long experience of Russia in the development of the Red Data Books of Soils is analyzed, and several conclusions aimed at improving the efficiency of special protection of soils in Russia and contiguous countries are made.  相似文献   
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Lambs of an age of 2 or 4 months and of an average live weight of 14.7 and 27.4 kg resp. received rations consisting of 44% cereals, 46% dried sugar beet pulp, 6% wheat starch, 2% urea and 2% mineral-vitamin mixture. The crude protein content was 17.1 and 15.9% resp. in the dry matter, that of native crude protein 10.6 and 9.4% resp. During a 6-day N balance period 8 and 16 g 15N urea resp. with a 15N excess (15N') of 9.26 and 9.40 atom-% were fed orally instead of commercial feeding urea. There were no significant differences between the two age groups with regard to the digestibility of the organic matter and the crude nutrients. The average N balance of 372 +/- 85 mg/kg LW 0.75/day were in the intermediate range of N retention capacity and accounted for 26 +/- 5% of the consumed N. N retention in per cent. was slightly lower in younger lambs. Projections of urea utilization in a quasi stationary state resulted in an efficiency of the utilization of 33 +/- 4%. The dismembering of the lambs at the end of the main period showed between 0.02 and 0.22 atom-% 15N' in the total N, TCA precipitable N and amino acid N of the meat. At between 0.24 and 0.38 atom-% 15N' they were highest in the heart and jaw muscles. The quota of 15N' amounts found in the total N of the meat were 10.6 +/- 3% of the 15N-intake and 20.1 +/- 5.1% of the 15N' amount remaining in the body. The bones contained 7.7 +/- 1.7% and the fleece 7.9 +/- 3.1% of the 15N'-intake. Generally seen, the total N and urea utilization was slightly lower in younger lambs than in older ones.  相似文献   
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