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资源动物学课程教学探讨
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作者 杨承忠 唐发辉 +1 位作者 黄艳梅 赵元莙 《教育教学论坛》 2019年第39期182-183,共2页
资源动物学关注全球生物多样性、资源动物利用、经济价值和可持续发展等重要问题,是高等学校生物学领域本科生开设的一门重要课程.文章从资源动物学的教学内容和课堂形式出发就如何提高资源动物学的教学质量进行探讨.
关键词 资源动物学 教学内容 课堂形式
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Effects of long-term medieval agriculture on soil properties:A case study from the Kislovodsk basin,Northern Caucasus,Russia
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作者 CHERNYSHEVA Elena KHOMUTOVA Tatiana +2 位作者 FORNASIER Flavio KUZNETSOVA Tatiana BORISOV Alexandr 《Journal of Mountain Science》 SCIE CSCD 2018年第6期1171-1185,共15页
The chemical properties and biological activities of soils were studied in the vicinity of the medieval settlement Podkumskoe-3 in the Kislovodsk basin(Northern Caucasus, Russia). Between the 5 th and 8 th centuries t... The chemical properties and biological activities of soils were studied in the vicinity of the medieval settlement Podkumskoe-3 in the Kislovodsk basin(Northern Caucasus, Russia). Between the 5 th and 8 th centuries this area was ploughed regularly, but it was then abandoned up to the present day. It has been established that past human activity leads to soil undergoing significant transformations in terms of microbial communities and enzyme activity, and that such changes are maintained over long periods. Long-term manuring in the middle of the first millennium AD led to an increase in organic carbon content and the accumulation of nitrate nitrogen. Soils of ancient abandoned fields are associated with increases in microbial biomass, number of saprotrophic bacteria, urease activity, and fungal mycelium biomass. The observed changes in the microbiological and biochemical properties of soil were conditioned by secondary anthropogenically induced succession after the abandonment of arable lands. 展开更多
关键词 Anthropogenic soils Manuring Enzymeactivity Microbial biomass North Caucasus MiddleAges
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Heat Transfer Validation and Comparative Evaluation of Biochar Yield from Pyrolysis Cook Stove
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作者 Teka Tesfaye Mengesha Ancha Venkata Ramayya 《Journal of Agricultural Science and Technology(B)》 2015年第6期389-400,共12页
The developing world still largely depends on biomass, such as wood, animal dung and agricultural waste for domestic fuel sources that are typically burned in traditional stoves. Ethiopia has different biomass resourc... The developing world still largely depends on biomass, such as wood, animal dung and agricultural waste for domestic fuel sources that are typically burned in traditional stoves. Ethiopia has different biomass resource for biochar production, through pyrolysis cook stove co-producing biochar. Coffee husks are the major solid residues from the handling and processing of coffee in the study area. This study was to evaluate the biochar co-producing pyrolysis cook stove with respect to heat transfer through the bed and biochar yield. From allothermal type of pyrolysis cook stove, the stove design was selected for both the computational fluid dynamic (CFD) simulation and experimental measurements. ANSYS 14.5 was used for CFD simulation of the wood combustion. The production of biochar from coffee husk, corncob and sawdust at different heating times, bed and stove surface temperature were undertaken. Bulk density, pH and surface area of the biochar were measured. While good agreement between simulation and experimental result was obtained in the conduction phase during pyrolysis, deviation between the two on account of the effect of volatile gas in changing the temperature trend within the biomass bed was noticed. Within the biomass type, the maximum mean biochar yield (38.91%) was seen from coffee husk. In the case of different stove designs, the minimum mean biochar yield (27.11%) was found from normal Anila stove. The pH of biochar is found to be significantly affected by the type of biomass (9.83 mean for corncob and coffee husk, 6.43 mean for sawdust), heating time (9.19 mean for 90 min and 8.01 mean for 30 min) and stove type (9.52 mean for normal Anila and 8.01 mean for flangeless Anila continuous feeding type). In fact, the type of biomass is observed to significantly affect the bulk density and surface area ofbiochar. 展开更多
关键词 BIOCHAR temperature cook stove BIOMASS PYROLYSIS soil CFD simulation.
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Influence of Prospecting and Crude Oil Production on Geoecological Parameters of Permafrost
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作者 Sergey N. Buldovich Elena V. Stanis 《Journal of Environmental Science and Engineering(B)》 2012年第2期244-249,共6页
The large reserves ofoil are disposed in zones of permafrost in shelf and continental fields. In Europe the subarctic and arctic tundra are abundant only in Nenetsky autonomous area and in the north-east of the republ... The large reserves ofoil are disposed in zones of permafrost in shelf and continental fields. In Europe the subarctic and arctic tundra are abundant only in Nenetsky autonomous area and in the north-east of the republic of Komi. Oil and gas production activity has threatened richest biological resources and health of the population of the region. A singularity of petroliferous fields of the north of Russia is the existence of the thick strata of permafrost. On top of them different heat-insulating overlying layers (snow, biogenic covers) reside. State and dynamics of permafrost cause progressing dangerous exogenic geoecological processes, which are exhibited completely. State of permafrost is instituted by exchange of heat in near-surface strata of a geological section. During the development of oil fields there is a disturbance of a temperature schedule of permafrost. For estimation of technical attack the analytical computational method of influence of the different factors on value of annual heat exchange and prediction of geocryological conditions is proposed. It is shown, that such dangerous phenomena as degradation of permafrost and thermokarst would develop in the first place, which would cause the destruction of natural ecosystems. 展开更多
关键词 Heat exchange PERMAFROST thermal parameters of rocks seasonal thawing layer thermokarst.
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Wildlife Conservation and Research in China
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作者 WEI Fuwen LOU Zhiping 《Bulletin of the Chinese Academy of Sciences》 2010年第4期222-227,共6页
Wildlife resources are important strategic bioresources in China. This paper analyzes the current threats to China’s wildlife, outlines achievements made by Chinese conservation biologists, and presents suggestions f... Wildlife resources are important strategic bioresources in China. This paper analyzes the current threats to China’s wildlife, outlines achievements made by Chinese conservation biologists, and presents suggestions for future developments in this field. The Chinese Academy of Sciences (CAS) plays an important role in the conservation of wildlife and provides significant intellectual support for conservation research and sustainable development. 展开更多
关键词 BIODIVERSITY wildlife resources endangered animals conservation biology
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From foraging to autonoetic consciousness: The primal self as a consequence of embodied prospective foraging 被引量:3
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作者 Thomas T. HILLS Stephen BUTTERFILL 《Current Zoology》 SCIE CAS CSCD 2015年第2期368-381,共14页
The capacity to adapt to resource distributions by modulating the frequency of exploratory and exploitative behaviors is common across metazoans and is arguably a principal selective force in the evolution of cognitio... The capacity to adapt to resource distributions by modulating the frequency of exploratory and exploitative behaviors is common across metazoans and is arguably a principal selective force in the evolution of cognition. Here we (I) review recent work investigating behavioral and biological commonalities between external foraging in space and internal foraging over envi- ronments specified by cognitive representations, and (2) explore the implications of these commonalities for understanding the origins of the self. Behavioural commonalities include the capacity for what is known as area-restricted search in the ecological literature: this is search focussed around locations where resources have been found in the past, but moving away from locations where few resources arc found, and capable of producing movement pattems mimicking L6vy flights. Area-restricted search shares a neural basis across metazoans, and these biological commonalities in vertebrates suggest an evolutionary homology be- tween external and internal foraging. Internal foraging, and in particular a form we call embodied prospective foraging, makes available additional capacities for prediction based on search through a cognitive representation of the external environment, and allows predictions about outcomes of possible future actions. We demonstrate that cognitive systems that use embodied prospec- tive foraging require a primitive sense of self, needed to distinguish actual from simulated action. This relationship has implica- tions for understanding the evolution of autonoetic consciousness and self-awareness. 展开更多
关键词 Self-projection Mental time travel Episodic future thinking FORAGING CONSCIOUSNESS
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