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新型生态保水剂施量对兰州新区土壤微环境及马铃薯产量效益的影响
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作者 邓超超 张靖 +5 位作者 周琦 宿翠翠 王振龙 施志国 魏域斌 周彦芳 《节水灌溉》 北大核心 2024年第12期12-18,共7页
探索新型生态保水剂施量对兰州新区土壤微环境和马铃薯产量效益的影响,明确新型生态保水剂施用效果和筛选最佳施量。以新型生态保水剂为材料(中国科学院上海应用物理研究所研发),采用大田试验方法,按保水剂施量设4个处理(CK:0,B3:45 kg/... 探索新型生态保水剂施量对兰州新区土壤微环境和马铃薯产量效益的影响,明确新型生态保水剂施用效果和筛选最佳施量。以新型生态保水剂为材料(中国科学院上海应用物理研究所研发),采用大田试验方法,按保水剂施量设4个处理(CK:0,B3:45 kg/hm^(2),B5:75 kg/hm^(2),B7:105 kg/hm^(2))研究滴灌模式下保水剂施量对兰州新区土壤水分、土壤酶活性、土壤呼吸速率的动态变化规律和马铃薯产量效益的影响。结果表明:与CK相比,施新型生态保水剂处理组显著提高了马铃薯生育期0~40 cm土层土壤体积含水量(5.24%~11.41%);随新型生态保水剂施量递增,0~40 cm土层土壤体积含水量逐渐增加后趋于稳定,B5、B7处理间差异不显著。土壤脲酶、蔗糖酶、过氧化氢酶活性及土壤呼吸速率均随马铃薯生育时期推进呈“单峰”曲线变化,块茎膨大期达峰值;与CK比较,施用新型生态保水剂处理组0~40 cm土层土壤脲酶、蔗糖酶、过氧化氢酶活性分别提高10.40%~24.35%、3.98%~10.06%、3.15%~8.11%,呼吸速率增强23.32%~25.51%,B5、B7处理间差异不显著。施用保水剂能够显著提高马铃薯产量和商品薯率,降低小薯率;与CK比较,B5、B7处理马铃薯增产9.53%~10.15%,总产值提高15.23%~15.66%。综合不同施量新型生态保水剂在兰州新区马铃薯生产实际中的应用效果,认为生态保水剂施量75kg/hm^(2)可以达到灌溉水资源利用效率、土壤微环境和马铃薯产量效益的多重提升。 展开更多
关键词 兰州新区 生态保水 马铃薯 土壤水分 土壤微环境 土壤酶活性 土壤呼吸 产量效益
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Discussion on Action and Potential of Fenlong Megascience in the Symbiosis between Human and Nature 被引量:4
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作者 韦本辉 申章佑 +6 位作者 周佳 周灵芝 李艳英 劳承英 甘秀芹 胡泊 韦元波 《Agricultural Science & Technology》 CAS 2017年第12期2303-2308,2311,共7页
The fourth new farming model Fenlong is identified as megascience for the first time. Fenlong can be directly applied to farming of farmland, remoulding of mortar black soil and saline alkali land and development of d... The fourth new farming model Fenlong is identified as megascience for the first time. Fenlong can be directly applied to farming of farmland, remoulding of mortar black soil and saline alkali land and development of degraded grassland. Deep loosening can create huge soil reservoirs, reduce fertilization, promote indi- rectly the improvement of river water fisheries and water sources and the upgrading of shaping and hydropower industry, thus making a new round of mobilization and pooling of natural resources. As a result, the nature is able to produce good food needed by human, the spatial dimension of the land is increased, the natural pre- cipitation storage is increased, the flood and drought disasters are reduced, the eco-environment is improved, and the economic benefits are increased. Fenlong is not restricted to global application by ecological region and crop variety and is not subject to the time-space constraints for a hundred thousand years. On the basis of utilizing the heaven and earth resources, it brings about a huge effect of mega- science. Compare with traditional farming, the depth under the mode of Fenlong is increased by 2-3 times, the contents of nutrient, water, oxygen and microorganism in the soil are increased by 10%-200%, the content of pale salt is increased by 20%-40%, the temperature is increased by 2-4 ~C, and the photosynthetic efficiency of crops is improved by 10%. Under the cultivation mode of Fenlong, the yield of crop applied with no fertilizers is increased by more than 10%, crop yield is still in- creased by more than 5% when the application amount of chemical fertilizer is re- duced by 10%-20%. Under the farming mode of Fenlong combined with no in- crease in fertilization, the crop yield, crop quality, farming efficiency, natural precipi- tation storage and air humidity are increased by 10%-50%, 5%, 15%, 100% and 5%, respectively, and the emissions of methane and other gases are reduced by more than 5%. Even in mortar black soil, saline alkali land and degraded grassland, the yield is still increased by 15%-50%. These improvement effects can last for many years, helping achieve the real harmonious coexistence between human and nature. 展开更多
关键词 Fenlong Megascience Autogeneration Yield and quality improvement Water conservation ecology Harmonious coexistence between human and nature
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Fenlong Cultivation-the Fourth Set of Farming Methods Invented in China 被引量:17
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作者 韦本辉 《Agricultural Science & Technology》 CAS 2017年第11期2045-2048,2052,共5页
The basic theory and effect of the new farming method of "Fenlong" cultivation which has been included in the main extension technology of Ministry of Agriculture of the People's Republic of China is fully illustra... The basic theory and effect of the new farming method of "Fenlong" cultivation which has been included in the main extension technology of Ministry of Agriculture of the People's Republic of China is fully illustrated for the first time, and it is the fourth set (generation) of farming modes and methods following manpower, animal and mechanical (tractor) farming. It follows the natural law to achieve soil activation, water saving, oxygen increase, warming and desalination through the active use of natural resources like soil, rainfall and solar energy, thereby promoting a new round of natural agricultural production and quality improvement and water con- servation, which has crop yield increase by 10%-30%, quality improvement of 5%, natural precipitation retaining increase by100%. The characteristics and mechanism are the use of spiral drill for one-time completion of the land preparation by drilling vertically to 30-50 cm of soil layer through high speed peeling. After instant high temperature and many fierce impacts, mechanical frictions, it could achieve the multiplication of the number of loose soil, soil physical modification and expansion of the soil nutrients, reservoirs, oxygen, microorganisms ("Four pools"). Fenlong cultivation can give birth to new farming culture and civilization, and it can achieve the physical "desalinized" transformation and utilization of saline soil. The formation of Fenlong green farming technology system makes it possible to invent the farming tools of "serf-propelled Fenlong machinery" that has got the patent, and it is the method for farmland (dry land, paddy field) Fenlong cultivation, saline-alkali soil smash-ridging cultivation and for the abundance of grass ecology on degraded grassland. The application of Fenlong "4+1" (arable, saline-alkali soil, grasslands, Sponge City+rivers) green development in China can achieve the "double safety" of food and living space. 展开更多
关键词 Fenlong cultivation The fourth set (generation) of new farming methods Activation and utilization of natural resources Improvement of production and quality Water conservation ecology
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Substantive Characteristics of Water and Soil Conservation and Ecological Civilization Construction in China 被引量:5
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作者 蔡艳蓉 冯兴平 《Agricultural Science & Technology》 CAS 2015年第6期1251-1258,共8页
Water and soil conservation is an important part of eco-civilization con-struction. It is a major part of eco-construction and lifeline of social and economy development. Therefore, water and soil conservation is of g... Water and soil conservation is an important part of eco-civilization con-struction. It is a major part of eco-construction and lifeline of social and economy development. Therefore, water and soil conservation is of great significance in maintaining eco-safety. The research concluded status quo and characters of water and soil losses in China and analyzed water and soil conservation and construction of eco-civilization from the perspectives of water and soil conservation and con-struction of eco-civilization. 展开更多
关键词 Water and soil losses Water and soil conservation Ecological civiliza-tion Ecological civilization construction
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Analysis on Countermeasures of Water and Soil Conservation and Eco-environment Construction in China 被引量:4
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作者 冯兴平 《Agricultural Science & Technology》 CAS 2015年第2期373-379,共7页
With economy development,human destruction of eco-environment is deteriorating,which has become a key treatment nationwide.What's more,eco-environment construction is proceeding and multi-eco-environment projects are... With economy development,human destruction of eco-environment is deteriorating,which has become a key treatment nationwide.What's more,eco-environment construction is proceeding and multi-eco-environment projects are developing.Water and soil conservation and eco-environment construction should be a strategic task long-term insisted on,which is a part of agricultural construction.The research analyzed the relationship between water and soil conservation with eco-environment,concluded the process of ecological civilization construction in promoting water and soil conservation,and proposed countermeasures,laying foundation for water and soil conservation and ecological construction. 展开更多
关键词 Water and soil erosion Water and soil conservation Construction of ecoenvironment Economic sustainable development Strategic tasks
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粉垄、“粉垄学”挖掘利用天地资源造福全人类 被引量:1
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作者 韦本辉 《世界生态学》 2019年第3期193-198,共6页
“粉垄技术”能使土地松土量增加1~2倍、保水和氧气增加1倍、速效养分增加10%~30%、降盐20%~40%、甲烷等气体减排10%、地面空气湿度提升10%以上和作物净光合效率提高10%~30%、生物量增加20%~30%,具有作物增产10%~50%、提质5%、保水1倍... “粉垄技术”能使土地松土量增加1~2倍、保水和氧气增加1倍、速效养分增加10%~30%、降盐20%~40%、甲烷等气体减排10%、地面空气湿度提升10%以上和作物净光合效率提高10%~30%、生物量增加20%~30%,具有作物增产10%~50%、提质5%、保水1倍及生态改善等效果与定力;本文首次提出建立全新的研究领域——“粉垄学”(“粉垄天地资源学”),研究内容包括粉垄全层耕、底层耕(遁耕)及农机装备学、耕作学、作物栽培学、水资源利用学(天然降水、农田水利、地下水资源等)、盐碱地改造利用学、宜耕退化草原改造学、荒漠化土地生态重建学、生态环境学、气候变化学和经济社会发展学等,阐明理论、丰富技术,为承载全球人口由70多亿发展到100亿并助力人与自然互利共生,提供重大平台。 展开更多
关键词 粉垄 全层耕底层耕(遁耕) 粉垄学 “天地资源”增量利用 增产提质保水生态
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Exploration of Water and Soil Conservation's Function in Construction of Eco-environment 被引量:2
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作者 张丰良 冯兴平 《Agricultural Science & Technology》 CAS 2015年第7期1544-1551,共8页
Eco-environment lays foundation for human existence and development, and social and economy evolvement. Therefore, it is a fundamental principle to pro- tact and construct eco-environment and achieve sustainable devel... Eco-environment lays foundation for human existence and development, and social and economy evolvement. Therefore, it is a fundamental principle to pro- tact and construct eco-environment and achieve sustainable development. With ur- ban development, and destruction on natural environment, however, the issue of water and soil losses has become a serious problem, affecting people's life and production. The research, therefore, explored the role of water and soil conservation in ecological civilization construction, including bomprehensive treatment of water storage and sand reduction, improving agricultural structure and advancing rural econ- omy, relieving the conflict between supply and demand of water resources, improv- ing eco-environment in mountainous regions and accelerating eco-construction. 展开更多
关键词 Water and soil conservation ECO-ENVIRONMENT Fundamental national policy
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A review of soil and water conservation in China 被引量:1
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作者 张兴昌 邵明安 +2 位作者 李世清 Peng Keshan 《Journal of Geographical Sciences》 SCIE CSCD 2004年第3期259-274,共16页
The preservation and sustainable development of soil and water resources isone of the basic principles for the development of China. Throughout the course of history, all thesocial improvement and economic development... The preservation and sustainable development of soil and water resources isone of the basic principles for the development of China. Throughout the course of history, all thesocial improvement and economic development are deeply concerned with soil loss and ecologicalenvironmental protection. It is now a common sense that soil and water conservation is the safetyinsurance for national ecology and its development. For the past long period of time, soil and waterloss has been recognized as 'the No.1 killer' to the ecological environment. The nation is on thestags of the critical conditions for its development. China has massive mountain and upland areawith complicated geological conditions and accelerated human destruction and serious soil and waterloss. Based on rich historical documents, renovating experience and detailed analysis of the datacollected in field experiments and field surveys for soil and water conservation, this paper aims toreview the general characteristics of soil and water loss, to explore the relationship between soiland water conservation and sustainable economic development, and to provide relevant strategies forsoil and water conservation in China. 展开更多
关键词 soil and water conservation ecological security ecological construction China
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Policy and Practice Progress of Watershed Eco-compensation in China 被引量:6
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作者 ZHANG Huiyuan LIU Guihuan +1 位作者 WANG Jinnan WAN Jun 《Chinese Geographical Science》 SCIE CSCD 2007年第2期179-185,共7页
The ecological protection of the watersheds in China is being confronted with a lot of problems such as soil and water erosion, water pollution at present. Therefore watershed eco-compensation is becoming a question o... The ecological protection of the watersheds in China is being confronted with a lot of problems such as soil and water erosion, water pollution at present. Therefore watershed eco-compensation is becoming a question of common interest. Based on the analyses of the major problems and their origins in the watershed protection in China, the paper discusses the concerned policies including relative rules and laws, financial policies and water right transaction policies. Simultaneously the paper reviews the practices carried out in China, including the ecological construction project in the western China, the trans-provincial eco-compensation practice and the small watershed eco-compensation practice. According to the present situation of eco-compensation practices and the future policy requirement, this paper finally puts forward four key problems to be solved in the watershed eco-compensation of China in the future. 展开更多
关键词 WATERSHED eco-compensation ecological protection
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Types of Ecological Revetments in Hydraulic Engineering 被引量:1
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作者 RONG Yunjie LIU Jingqiang LIU Qianyu 《Journal of Landscape Research》 2018年第2期1-4,共4页
Compared with traditional bank protection, ecological revetments, as a new type of bank protection, can ensure the sustainable and healthy development of river ecology and has broad application prospects. In this pape... Compared with traditional bank protection, ecological revetments, as a new type of bank protection, can ensure the sustainable and healthy development of river ecology and has broad application prospects. In this paper, the design principles for ecological revetments and the factors that need to be considered in the selection of revetment plants were summarized; and the types of ecological revetments commonly used in water conservancy projects were summarized and classified according to the proportion of natural materials in revetment materials through domestic and foreign research and engineering examples, and their applicable scope and relevant merits were introduced. In conclusion, ecological revetments should get rid of its own limitations in the practical application process, and the river regulation scheme and revetment type should be selected comprehensively and flexibly combined with the status quo. 展开更多
关键词 Ecological revetments Design principles Revetment types Engineering measures
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ECO-ENVIRONMENT CHANGE AND SOIL EROSION PROCESS IN THE RECLAIMED FORESTLAND OF THE LOESS PLATEAU 被引量:1
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作者 ZHAXiao-chun TANGKe-li 《Chinese Geographical Science》 SCIE CSCD 2003年第3期232-237,共6页
Serious soil erosion has made the eco-environment fragile in the Loess Plateau. Based on the 10-year data observed from 1989 to 1998 in the Ziwuling Survey Station in loess hilly region, the eco-environment change and... Serious soil erosion has made the eco-environment fragile in the Loess Plateau. Based on the 10-year data observed from 1989 to 1998 in the Ziwuling Survey Station in loess hilly region, the eco-environment change and soil erosion process in reclaimed forestland were studied in this paper. The results showed that the intensity of man-made soil erosion caused by forestland reclamation was 1000 times more than that of the natural erosion. From the analysis of soil physical and mechanical properties, in the 10th year after forestland was reclaimed, the clay content and physical clay content decreased 2.74 percentage point and 3.01 percentage point respectively, the >0.25mm waterstable aggregate content decreased 31.59 percentage point, the soil bulk density increased and soil shear strength decreased, all of which were easier to cause soil erosion. The correlation analysis showed that >0.25mm waterstable aggregate content was the key factor affecting soil erosion, and the secondary factors were soil coarse grain and soil shear strength. The relation between the >0.25mm waterstable aggregate content, the soil sheer strength and the soil erosion intensity were analyzed, which showed that the first year and the seventh erosion year were the turn years of the soil erosion intensity after the forestland was reclaimed, revealed that the change of eco-environment was the main cause to accelerate soil erosion, and the worse environment caused soil erosion to be serious rapidly. 展开更多
关键词 loess hilly region reclaimed forestland soil erosion eco-environmentchange
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Phosphorus Biogeochemical Cycle Research in Mountainous Ecosystems 被引量:15
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作者 WU Yan-hong ZHOU Jun +4 位作者 YU Dong SUN Shou-qin LUO Ji BING Hai-jian SUN Hong-yang 《Journal of Mountain Science》 SCIE CSCD 2013年第1期43-53,共11页
Phosphorus(P),as a limiting nutrient,plays a crucial role in the mountainous ecosystem development.Its biogeochemical cycle in mountainous ecosystems determines the bioavailability and sustainable supply of P,and thus... Phosphorus(P),as a limiting nutrient,plays a crucial role in the mountainous ecosystem development.Its biogeochemical cycle in mountainous ecosystems determines the bioavailability and sustainable supply of P,and thus becomes a crucial process which needs to be fully understood and described for ecological and environmental conservation.However,most of research about P biogeochemical processes has been carried out in aquatic environment and agronomic field,but rare researches have been done in mountain ecosystem.In the present review,we summarize researches on P biogeochemical cycle concerning mountain ecosystem in recent decades,including rock weathering,the release,transformation and bioavailability of P,interactions between the P biological cycle and microbial and plant life,as well as the development of models.Based on the state of art,we propose the future work on this direction,including the integration of all these research,the development of a practical model to understand the P biogeochemical cycle and its bioavailability,and to provide a reference for ecological and environmental conservation of mountainous ecosystems and lowland aquatic systems. 展开更多
关键词 Phosphorus Biogeochemical cycle Weathering Microbe and plant Model Mountainous ecosystem
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Assessment of the Ecological Security in the Three Gorges Reservoir Area by Using the Ecological Footprint Method 被引量:11
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作者 WANG Haiming WANG Hai'e +4 位作者 SUN Hongyang WANG Xiaolan LIAO Xiaoyong CHEN Zhijian LI Xianwei 《Journal of Mountain Science》 SCIE CSCD 2012年第6期891-900,共10页
The ecological footprint concept and its calculation models are useful for the measurement of the sustainable level of social and economic development.The ecological security situation of the Three Gorges Reservoir Ar... The ecological footprint concept and its calculation models are useful for the measurement of the sustainable level of social and economic development.The ecological security situation of the Three Gorges Reservoir Area(TGRA) was evaluated using this concept in this study.The construction of the Three Gorges Reservoir has led to the change in the ecology and immigration status of TGRA.The ecological footprint method is an important means to study the regional ecological security.Our results suggested that,by excluding the areas for biodiversity conservation(12% of the total land),the ecological footprint per capita was 0.57895 ha,which exceeded the ecological carrying capacity in TGRA.The total ecological deficit was found to be 11,522,193.34 ha,accounting for 95.02% of the ecological carrying capacity.These findings suggested that the ecological security of TGRA was not good.In order to compensate for the ecological deficit,it was essential to introduce natural resources from other regions. 展开更多
关键词 Three Gorges Reservoir Area(TGRA) Ecological footprint Ecological security
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Legal study on water environmental protection of Three Gorges Reservoir Area
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作者 邓禾 《Journal of Chongqing University》 CAS 2007年第1期22-29,共8页
Water environment security of the Three Gorges Reservoir Area has become a more extensive concern since the impoundment of the reservoir. This paper describes the existing water environmental hazards and defects in cu... Water environment security of the Three Gorges Reservoir Area has become a more extensive concern since the impoundment of the reservoir. This paper describes the existing water environmental hazards and defects in current legal system for water environmental protection in this area, and also discusses their possible causes and potential problems in the future based on first hand materials and other literature. According to the theories of integrated river basin management and environmental equity principle, legal proposals are put forward, which include building an unitary legal system dedicated to the Reservoir Area, setting up a basin authority of the Yangtze River to preside over the resources protection and development, using interests' compensation system to solve interest conflicts among different reaches, and making concrete regulations to direct public participation in water environmental security protection of the Three Gorges Reservoir Area. 展开更多
关键词 Three Gorges Reservoir area water environmental security legal measure
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Spatial Distribution and Sources Identification of Polycyclic Aromatic Hydrocarbons in Wolong Lake, Northeast China 被引量:1
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作者 ZHAO Guanghui CHANG Wenyue +5 位作者 YAN Jinxia LI Xiaojun TONG Dongli ZHAO Ranran Sharley James DAVID TAI Peidong 《Chinese Geographical Science》 SCIE CSCD 2017年第6期1003-1012,共10页
The aquatic ecosystem maybe significantly affected by polycyclic aromatic hydrocarbons(PAHs) released from fresh water sediments. In order to protect biodiversity, the spatial distribution and sources of PAHs in the s... The aquatic ecosystem maybe significantly affected by polycyclic aromatic hydrocarbons(PAHs) released from fresh water sediments. In order to protect biodiversity, the spatial distribution and sources of PAHs in the sediment of Wolong Lake in Northeast China were studied. A total of 17 surface sediment samples were collected and 12 PAHs were analyzed. The results were as follows. The concentration of total PAHs(TPAHs) ranged between 1412.9 μg/kg and 3948.3 μg/kg(dry weight). Indeno [1, 2, 3-c, d] pyrene was the dominant contaminant which accounted for 87%–98% of TPAHs. Diagnostic ratios of PAHs and principal component analysis showed that biomass combustion and vehicle emissions were likely to be the dominant sources of PAHs in the sediment. PAHs can be considered safe in the context of environmental and human health protection, based on the overall toxicity. Individual PAHs were positively correlated with total organic carbons. These results will be helpful to control PAHs and protect the aquatic ecosystem in the lake. 展开更多
关键词 polycyclic aromatic hydrocarbons (PAHs) Wolong Lake lake sediment contaminant oxicity spatial distribution
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Energy flow in Branchiura sowerbyi (Oligochaeta: tubificidae) in a shallow macrophyte-dominated lake, Biandantang Lake
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作者 闫云君 梁彦龄 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第4期403-407,共5页
The energy flow of Branchiura sowerbyi was studied for the first time in China in a shallow macrophytic lake, Biandantang Lake, Hubei Province. The energy flow was calculated from the measurement of flesh production (... The energy flow of Branchiura sowerbyi was studied for the first time in China in a shallow macrophytic lake, Biandantang Lake, Hubei Province. The energy flow was calculated from the measurement of flesh production (12.5241kJ/m2a), egestion (517.7302kJ/m2a), metabolism (38.3273 kJ/m2a), and excretion (4.3798kJ/m2a). The net growth efficiency of the species is about 22.7%, which accords well with the generally reported value for oligochaetes. In addition, the relationship between starvation respiration (R, mgO2/ind穌), wet weight (Ww, mg) and temperature (T, C) were also measured, with the regression function being R=0.008 Ww0.736 e0.050T. 展开更多
关键词 Biandantang Lake energy flow Branchiura sowerbyi
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Edible Peanut Worm(Sipunculus nudus) in the Beibu Gulf: Resource, Aquaculture, Ecological Impact and Counterplan 被引量:10
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作者 LI Junwei XIE Xiaoyong +2 位作者 ZHU Changbo GUO Yongjian CHEN Suwen 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第5期823-830,共8页
Sipunculus nudus is an important economic species because of its high nutritional and medicinal values. The exploitation and utilization of S. nudus primarily occur in the coastal regions of the Beibu Gulf. However, w... Sipunculus nudus is an important economic species because of its high nutritional and medicinal values. The exploitation and utilization of S. nudus primarily occur in the coastal regions of the Beibu Gulf. However, wild resource of S. nudus is rapidly decreasing because of the overexploitation, which has led to considerable developments of artificial breeding techniques. The cultivation scale of S. nudus has increased in response to successful artificial breeding; however, methods for culturing S. nudus in tidal flats or ponds require further study. Most studies have focused on the breeding, nutrition, medical value and ecological impact of these worms. Studies on the distribution, sediment requirements, nutrition characteristics, breeding techniques and aquaculture ecology of this species are summarized in this paper to promote the development of the aquaculture industry for S. nudus. The high biomass of S. nudus in the Beibu Gulf is positively correlated with the sediment characteristics and water quality of the region. The production of peanut worm has improved to some extent through culturing; however, the nutrient value and ecological environment problems have been observed, which reflect the over exploitation of trace elements and the sediment. These problems will worsen unless they are resolved, and the release of organic materials, nitrogen and phosphorus during harvesting impacts the coastal environment. Moreover, genetic erosion is a potential risk for larvae in artificial breeding programs in tidal flats. Therefore, culturing and collecting methods should be improved and the wild resource conservation should be implemented to promote the sustainable development of the peanut worm. 展开更多
关键词 breeding larvae aquaculture tidal nutrition cultivation erosion exploitation sustainable phosphorus
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Seasonal variations of rotifers from a high altitude urban shallow water body, La Cantera Oriente (Mexico City, Mexico)
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作者 Sergio González GUTIERREZ S.S.S. SARMA S. NANDINI 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第6期1387-1397,共11页
La Cantera Oriente is a shallow freshwater volcanic water body located at an altitude of 2 270 m above sea level in the Ecological Reserve of San Angel Pedregal of Mexico City (Mexico). In order to ensure the conser... La Cantera Oriente is a shallow freshwater volcanic water body located at an altitude of 2 270 m above sea level in the Ecological Reserve of San Angel Pedregal of Mexico City (Mexico). In order to ensure the conservation of its biological heritage including zooplankton, the present work was undertaken to quantify the seasonal changes in the diversity and density of rotifers and the selected physico- chemical variables during 2013-2014. Qualitative analysis of the zooplankton samples yielded 68 rotifer species which represented 24 genera in 15 families. Brachionus calyciflorus Pallas, 1766, B. quadridentatus Hermann, 1783, Polyarthra vulgaris Carlin, 1943, Lecane closterocerca (Schmarda, 1859) and Keratella cochlearis (Gosse, 1851) were the most common species. Preston plots of species frequency-density revealed that as many as 30% of the rotifer taxa were dominant throughout the year. The species with high population densities were Brachionus quadridentatus, Lecane closterocerca, Keratella cochlearis, and Lepadellapatella; their peak densities were 2 000, 1 000, 180 and 90 ind./L, all occurring in summer. Canonical correspondence analysis showed that Platyias quadricornis was related to the concentration of phosphates available in the environment and the conductivity, while B. quadridentatus was positively correlated with chlorophyll-a. The trophic status of the lake was eutrophic based on Chl-a content but oligotrophic with relation to the Braehionus: Trichocerca ratio. 展开更多
关键词 high altitude ZOOPLANKTON seasonal density dynamics LIMNOLOGY ROTIFERA
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Limiting drainage criterion for groundwater of mountain tunnel 被引量:1
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作者 程盼 赵炼恒 +2 位作者 李亮 邹金锋 罗伟 《Journal of Central South University》 SCIE EI CAS 2014年第12期4660-4668,共9页
Large amount of groundwater discharging from tunnel is likely to cause destruction of the ecological environment in the vicinity of the tunnel, thus an appropriate drainage criterion should be established to balance t... Large amount of groundwater discharging from tunnel is likely to cause destruction of the ecological environment in the vicinity of the tunnel, thus an appropriate drainage criterion should be established to balance the tunnel construction and groundwater.To assess the related problems, an limiting drainage standard ranging from 0.5 to 2.0 m3/(m·d) was suggested for mountain tunnels based on survey and comparative analysis. After that, for the purpose of verifying the rationality of the standard, a calculated formula for dewatering funnel volume caused by drainage was deduced on the basis of the groundwater dynamics and experience method.Furthermore, the equation about the relationship between water discharge and drawdown of groundwater table was presented. The permeability coefficient, specific yield and groundwater table value were introduced, and then combined with the above equation, the drawdown of groundwater table under the proposed limiting drainage criterion was calculated. It is shown that the proposed drainage standard can reach the purpose of protecting ecological environment under the following two conditions. One is the permeability coefficient ranges from 10-4 to 10-5 m/s and the specific yield ranges from 0.1 to 0.001. The other is the permeability coefficient varies from 10-6 to 10-8 m/s and the specific yield varies from 0.1 to 0.01. In addition, a majority of common geotechnical layers are involved in the above ranges. Thus, the proposed limiting drainage standard which ranges from 0.5 to 2.0 m3/(m·d) for mountain tunnel is reasonable. 展开更多
关键词 mountain tunnel groundwater dewatering funnel limiting drainage criterion drawdown of groundwater table
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The status and protection of the ecological environment in Heihe River water source district
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作者 Sun Jing 《International Journal of Technology Management》 2015年第5期4-7,共4页
This article discusses the status of the ecological environment in Heihe River water source district, and points out that the decline of the forest coverage, the degradation of the pasture and the shrinking back of th... This article discusses the status of the ecological environment in Heihe River water source district, and points out that the decline of the forest coverage, the degradation of the pasture and the shrinking back of the glacier, the increased soil erosion and other phenomena are the main ecological and environmental problems in this area. The main reason is the natural and man-made results. This article proposes the specific measures to protect the ecological environment in Heihe River water source district. 展开更多
关键词 Heihe River water source district Environmental degradation ANALYSIS Protection measures
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