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Heavy metals pollution in poultry and livestock feeds and manures under intensive farming in Jiangsu Province, China 被引量:183
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作者 CANGLong WANGYu-jun ZHOUDong-mei DONGYuan-hua 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第3期371-374,共4页
The heavy metals pollution in poultry and livestock feeds and manures under intensive farming in Jiangsu Province was investigated. 97 feed and manure samples were sampled from 31 farming plants in 10 major cities of ... The heavy metals pollution in poultry and livestock feeds and manures under intensive farming in Jiangsu Province was investigated. 97 feed and manure samples were sampled from 31 farming plants in 10 major cities of Jiangsu. 14 metals, including Zn, Cu, Pb, Cd, Cr, Ni, Mo, Mn, Ba, Co, Sr, Ti, As and Hg, were analyzed after samples acid digestion. The results showed that the most feed samples contained high concentration of metals exceeding National Hygienical Standard for Feeds. Meanwhile, it was found that Cu, Zn, Pb, Cd and Cr concentrations in animal manures were also high, for example, Cu concentration in a manure sample reached to as much as 1726 3 mg/kg. Heavy metals loading quantities in soil per year were then calculated when metals contaminated organic fertilizers were applied, and its effects on soil environmental quality were further evaluated. 展开更多
关键词 heavy metal intensive farming FEED MANURE Jiangsu Province
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广东三水市种植业系统的能值分析及其可持续发展 被引量:38
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作者 苏国麟 李谋召 +1 位作者 蓝盛芳 陈飞鹏 《农业现代化研究》 CSCD 北大核心 1999年第6期359-362,共4页
应用生态系统能值分析理论方法,定量分析广东省三水市种植业系统的物流和能流。结果表明:1997 年三水市种植业系统的经济投入明显高于广东省平均水平,与一些发达国家相近。其中人力和化肥投入分别占经济投入的45.6% 和22.8% ,这与充分... 应用生态系统能值分析理论方法,定量分析广东省三水市种植业系统的物流和能流。结果表明:1997 年三水市种植业系统的经济投入明显高于广东省平均水平,与一些发达国家相近。其中人力和化肥投入分别占经济投入的45.6% 和22.8% ,这与充分利用耕地(复种指数达307% )和多样化种养模式(基塘系统占总耕地30% )是分不开的。今后应加强物质能量多级利用,提高资源利用效率,扩大有机肥源、减少化肥的投入,走持续发展的农业道路。 展开更多
关键词 种植业 能值分析 三水市 可持续发展
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中国区域土壤表观氮磷平衡清单及政策建议 被引量:43
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作者 陈敏鹏 陈吉宁 《环境科学》 EI CAS CSCD 北大核心 2007年第6期1305-1310,共6页
利用OECD表观氮平衡模型框架,建立了中国表观氮磷平衡核算的框架、方法和数据库.模型结果表明,2003年中国土壤表观氮磷盈余总量分别为640×104t和98×104t,氮磷盈余强度分别为16.56 kg/hm2和2.53 kg/hm2.由于中国氮磷平衡区域... 利用OECD表观氮平衡模型框架,建立了中国表观氮磷平衡核算的框架、方法和数据库.模型结果表明,2003年中国土壤表观氮磷盈余总量分别为640×104t和98×104t,氮磷盈余强度分别为16.56 kg/hm2和2.53 kg/hm2.由于中国氮磷平衡区域分布严重不平衡,面临着氮磷盈余管理和氮磷缺损管理的双重压力.化肥和畜禽粪便是中国土壤氮磷投入最主要的来源,因此是中国氮磷盈余管理最佳切入点.由于各地氮磷投入结构各异,在氮磷盈余严重的中东部地区,不宜采用“一刀切”的政策,而应针对不同地区氮磷输入的特点进行氮磷盈余管理. 展开更多
关键词 表观氮磷平衡 清单 种植 养殖 氮磷输入 氮磷输出
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河北坝缘简育干润均腐土耕种过程中的退化研究 被引量:25
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作者 肖洪浪 赵雪 赵文智 《土壤学报》 CAS CSCD 北大核心 1998年第1期129-134,共6页
研究区位于中国干草原干润均腐土的东南缘、农牧交错带、荒漠化严重发展区。农业的大发展仅数十年历史,广种薄收、粗放经营形式下,土壤资源过度利用导致了耕种简育干润均腐土成为区内严重退化的类型,并集中地表现在养分、质地和保水... 研究区位于中国干草原干润均腐土的东南缘、农牧交错带、荒漠化严重发展区。农业的大发展仅数十年历史,广种薄收、粗放经营形式下,土壤资源过度利用导致了耕种简育干润均腐土成为区内严重退化的类型,并集中地表现在养分、质地和保水性三方面。在肥力退化过程中,养分剖面构型向干旱土类演替;表土粗化,平耕地粒度向风沙沉积特征发展;随耕种年限的增加,耕地在养分、质地以及容重退化的同时保水保肥能力降低。缓解与治理简育干润均腐土退化需推广保护性耕作措施,改造传统农业,增加投入。 展开更多
关键词 简育干润均腐土 耕种 退化 河北坝缘干草原
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我国农业环境污染的现状和成因及治理对策 被引量:36
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作者 杜江 罗珺 《农业现代化研究》 CSCD 北大核心 2013年第1期90-94,共5页
本文分析了改革开放以来我国农业化学品投入量大幅增加所产生的农业污染问题的现状,认为农业污染的形成与农业产业政策、城乡经济结构、污染治理资金、环境综合管理、农业环境政策、污染治理法律以及农民环境意识等因素有关。为有效解... 本文分析了改革开放以来我国农业化学品投入量大幅增加所产生的农业污染问题的现状,认为农业污染的形成与农业产业政策、城乡经济结构、污染治理资金、环境综合管理、农业环境政策、污染治理法律以及农民环境意识等因素有关。为有效解决农业污染问题,需采取以下措施:农业-环境政策一体化、建立环境友好的农业技术体系、实行流域的综合管理、增强农业污染环境管理能力、加大农民环境教育力度以及建立农业环境保护立法。 展开更多
关键词 农业面源污染 种植业 化学投入品 污染治理 环境教育 环境保护立法
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我国麝养殖种群现状及其养殖业发展的分析 被引量:33
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作者 李林海 黄祥云 +5 位作者 刘刚 王文霞 卫宁 刘燕 胡德夫 梦梦 《四川动物》 CSCD 北大核心 2012年第3期492-496,共5页
我国麝养殖是解决麝类野生种群保护和中医药麝香来源的关键环节,是极为重要的野生动物养殖业。通过调查得出,截至2011年全国养殖麝已达8400余头,主要分布于四川、陕西等省份;养殖麝种群雄雌比率为1∶0.97,成幼比率为1∶0.53,表明养殖麝... 我国麝养殖是解决麝类野生种群保护和中医药麝香来源的关键环节,是极为重要的野生动物养殖业。通过调查得出,截至2011年全国养殖麝已达8400余头,主要分布于四川、陕西等省份;养殖麝种群雄雌比率为1∶0.97,成幼比率为1∶0.53,表明养殖麝种群处于快速增长状态,种群结构基本合理。结合目前麝养殖业资料的调查,分析了养殖规模、养殖技术、种源管理、产业政策对麝养殖产业发展的作用并提出提升麝养殖业发展的对策。 展开更多
关键词 养殖种群 养殖业 现状 分析
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农田能量测算原理与指标体系的研究 被引量:20
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作者 尹钧 高志强 +1 位作者 张布雷 郑月英 《山西农业大学学报》 CAS 1998年第2期95-98,共4页
本研究根据美国、英国和中国等国对农业能量的大量研究和测算方法,结合国内农田投入和产出的实际情况,研究确定了农田系统主要农业生产资料,如:灌溉水、化肥、有机肥、耕作和主要作物产品的能量测算方法与折算标准,初步建立了适合... 本研究根据美国、英国和中国等国对农业能量的大量研究和测算方法,结合国内农田投入和产出的实际情况,研究确定了农田系统主要农业生产资料,如:灌溉水、化肥、有机肥、耕作和主要作物产品的能量测算方法与折算标准,初步建立了适合我国农业生产条件的农田能量指标体系,为开展农田能量的广泛研究提供重要依据。 展开更多
关键词 农田 灌溉能量测量 指标体系
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Research Progress in the Application of Chinese Herbal Medicines in Aquaculture: A Review 被引量:23
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作者 Hongyu Pu Xiaoyu Li +2 位作者 Qingbo Du Hao Cui Yongping Xu 《Engineering》 SCIE EI 2017年第5期731-737,共7页
Due to increasing safety concerns regarding human consumption of fish products, an increasing number of medicinal chemicals are prohibited from use in aquaculture. As a result, Chinese herbal medicines are being incre... Due to increasing safety concerns regarding human consumption of fish products, an increasing number of medicinal chemicals are prohibited from use in aquaculture. As a result, Chinese herbal medicines are being increasingly used, coining the use of the term "green medicine." Research shows that Chinese herbal medicines have many beneficial effects on fish, including growth promotion, enhancement of disease resistance, and improvement in meat quality. Many effective ingredients have been discovered in Chinese herbal medicines, which function to promote feed intake, improve meat flavor, and increase digestive enzyme activity. They also regulate and participate in processes that improve the specific and non-specific immunity of fish; however, the composition of Chinese herbal medicines is very complex and it is often difficult to identify the effective ingredients. This article reviews the latest research and application progress in Chinese herbal medicines regarding growth and feed utilization, immunity and disease resistance, and the meat quality of cultured fish. It also discusses research on the chemical constituents of classical Chinese medicinal herbs and problems with the application of Chinese herbal medicines in fish culture. This article concludes by proposing that future studies on Chinese herbal medicines should focus on how to cheaply refine and extract the effective ingredients in classical Chinese medicinal herbs, as well as how to use them efficiently in aquaculture. 展开更多
关键词 AQUACULTURE Chinese herbal medicines Fish farming Research progress
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Waste production in aquaculture:Sources,components and managements in different culture systems 被引量:23
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作者 Akeem Babatunde Dauda Abdullateef Ajadi +1 位作者 Adenike Susan Tola-Fabunmi Ayoola Olusegun Akinwole 《Aquaculture and Fisheries》 2019年第3期81-88,共8页
The intensification of aquaculture has emerged as a viable alternative for increasing aquaculture production due to competition that arose from the use of natural resources,such as land and water,by other production a... The intensification of aquaculture has emerged as a viable alternative for increasing aquaculture production due to competition that arose from the use of natural resources,such as land and water,by other production and developmental sectors.However,intensification demands increased inputs,such as fish and feed per unit culture area and,therefore,increased waste generation from the aquaculture production systems.The impact of waste products from aquaculture has increased public concern and threatens the sustainability of aquaculture practices.The need for increasing the production of aquaculture products cannot be overemphasized and,therefore,there is a need to develop culture systems that will increase fish production with efficient waste management in order to limit environmental degradation resulting from aquaculture wastes and ensure its sustainability.This paper reviewed various aspects of waste production from aquaculture,their sources,components,and methods of management,in different culture systems,primarily discussing waste production from feed,chemicals,and pathogens.We aimed to establish the sources of wastes,their contents,and potential harms to both the fish culture and the environment.Suggestions for managing wastes in different culture systems were made to ensure an improved and sustainable aquaculture production. 展开更多
关键词 Fish farming Aquaculture effluents Environmental degradation Waste management Sustainable aquaculture
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Numerical study of regional environmental carrying capacity for livestock and poultry farming based on planting-breeding balance 被引量:21
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作者 Lihong Peng Yu Bai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第9期1882-1889,共8页
In consideration of the need to maintain planting-breeding balance, this article examines the capacity of the soil in Putian City, Fujian Province to absorb livestock and poultry excreta, and computes the environmenta... In consideration of the need to maintain planting-breeding balance, this article examines the capacity of the soil in Putian City, Fujian Province to absorb livestock and poultry excreta, and computes the environmental carrying capacity for livestock and poultry farming (ECCLPF) in each district of the city in terms of the fertility characteristics of the soil in the city, as well as its mix of crops cultivated and farming methods. On the basis of the computations, this work proceeds to classify the alarm grades of the city's environmental carrying capacity for livestock and poultry framing, and assess the environmental impact of the livestock and poultry farming industry. The results of our study indicate that, the city's ECCLPF ranges from 8.27 to 23.23 heads per ha when computed on the basis of nitrogen, and from 5.79 to 24.53 heads per ha when computed on the basis of phosphorus. A comparison between our research findings and the existing farming scale in Putian reveals that, in certain parts of the city, ECCLPF is overburdened to varying degrees. Specifically, Chengxiang District is severely overburdened, Hanjiang District and Meizhou Island have a level of overburdening between virtual overburdening and significant overburdening, Licheng District is virtually overburdened, and Xiuyu, Xianyou, and Bei'an Districts have not exceeded their environmental carrying capacity and therefore have varying levels of potential for growth. 展开更多
关键词 livestock and poultry farming planting-breeding combination nitrogen and phosphorus balance alarm classification system
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农户种植业风险及其认知比较研究 被引量:13
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作者 西爱琴 陆文聪 梅燕 《西北农林科技大学学报(社会科学版)》 2006年第4期22-28,共7页
通过对浙江、上海、山东、湖北和安徽五个不同地区660户农户实地访问调查资料的分析发现:目前我国农户从事种植业生产经营的风险主要来源于气候等自然因素、农产品市场价格和农业生产资料价格;农户更关注农产品产量而非市场价格波动;在... 通过对浙江、上海、山东、湖北和安徽五个不同地区660户农户实地访问调查资料的分析发现:目前我国农户从事种植业生产经营的风险主要来源于气候等自然因素、农产品市场价格和农业生产资料价格;农户更关注农产品产量而非市场价格波动;在地区和作物层面上,具有不同生产特征和家庭特征的农户对种植业生产经营风险的认知具有一定的差异性;目前农户弱化种植业风险主要倾向于依靠自身的力量而较少依靠农业保险、农业组织及政府等外部力量。政府需要从完善信息发布体系、加强对农资市场管理、促进农村合作经济组织及农业保险的发展等方面入手,提高农户弱化生产经营风险的能力。 展开更多
关键词 农户 风险 认知 种植业
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Advances in greenhouse automation and controlled environment agriculture:A transition to plant factories and urban agriculture 被引量:21
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作者 Redmond Ramin Shamshiri Fatemeh Kalantari +5 位作者 K.C.Ting Kelly R.Thorp Ibrahim A.Hameed Cornelia Weltzien Desa Ahmad Zahra Mojgan Shad 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2018年第1期1-22,共22页
Greenhouse cultivation has evolved from simple covered rows of open-fields crops to highly sophisticated controlled environment agriculture(CEA)facilities that projected the image of plant factories for urban agricult... Greenhouse cultivation has evolved from simple covered rows of open-fields crops to highly sophisticated controlled environment agriculture(CEA)facilities that projected the image of plant factories for urban agriculture.The advances and improvements in CEA have promoted the scientific solutions for the efficient production of plants in populated cities and multi-story buildings.Successful deployment of CEA for urban agriculture requires many components and subsystems,as well as the understanding of the external influencing factors that should be systematically considered and integrated.This review is an attempt to highlight some of the most recent advances in greenhouse technology and CEA in order to raise the awareness for technology transfer and adaptation,which is necessary for a successful transition to urban agriculture.This study reviewed several aspects of a high-tech CEA system including improvements in the frame and covering materials,environment perception and data sharing,and advanced microclimate control and energy optimization models.This research highlighted urban agriculture and its derivatives,including vertical farming,rooftop greenhouses and plant factories which are the extensions of CEA and have emerged as a response to the growing population,environmental degradation,and urbanization that are threatening food security.Finally,several opportunities and challenges have been identified in implementing the integrated CEA and vertical farming for urban agriculture. 展开更多
关键词 smart agriculture greenhouse modelling urban agriculture vertical farming automation internet of things(IoT) wireless sensor network plant factories
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Modeling the relationship of land use change and some geophysical indicators for the interlock area of farming and pasturing in China 被引量:19
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作者 DENG Xiangzheng, LIU Jiyuan, ZHUANG Dafang, ZHAN Jinyan, ZHAO Tao(Inst. of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2002年第4期397-404,共8页
This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern China. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorph... This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern China. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorphic units and geophysical conditions-constraints or advantages. Additionally, it selects some indicators, according to the availability in acquiring and processing their quantitative data, to analyze the canonical correlations between the typical conversion of grassland and geophysical conditions. The preliminary study indicates that the physical conditions are of great advantages to the development of grassland. There exists significant correlation between land use change and some geophysical conditions. 展开更多
关键词 land use driving force interlock area of farming and pasturing China
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Internet of Things for the Future of Smart Agriculture: A Comprehensive Survey of Emerging Technologies 被引量:20
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作者 Othmane Friha Mohamed Amine Ferrag +2 位作者 Lei Shu Leandros Maglaras Xiaochan Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第4期718-752,共35页
This paper presents a comprehensive review of emerging technologies for the internet of things(IoT)-based smart agriculture.We begin by summarizing the existing surveys and describing emergent technologies for the agr... This paper presents a comprehensive review of emerging technologies for the internet of things(IoT)-based smart agriculture.We begin by summarizing the existing surveys and describing emergent technologies for the agricultural IoT,such as unmanned aerial vehicles,wireless technologies,open-source IoT platforms,software defined networking(SDN),network function virtualization(NFV)technologies,cloud/fog computing,and middleware platforms.We also provide a classification of IoT applications for smart agriculture into seven categories:including smart monitoring,smart water management,agrochemicals applications,disease management,smart harvesting,supply chain management,and smart agricultural practices.Moreover,we provide a taxonomy and a side-by-side comparison of the state-ofthe-art methods toward supply chain management based on the blockchain technology for agricultural IoTs.Furthermore,we present real projects that use most of the aforementioned technologies,which demonstrate their great performance in the field of smart agriculture.Finally,we highlight open research challenges and discuss possible future research directions for agricultural IoTs. 展开更多
关键词 Agricultural internet of things(IoT) internet of things(IoT) smart agriculture smart farming sustainable agriculture
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Heavy Metal Contamination of Agricultural Soils in Taiyuan, China 被引量:20
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作者 LIU Yong WANG Huifeng +1 位作者 LI Xiaoting LI Jinchang 《Pedosphere》 SCIE CAS CSCD 2015年第6期901-909,共9页
To evaluate the current state of the environmental quality of agricultural soils in Taiyuan City, a hotspot for China's industrial development, the concentrations of 8 heavy metals in soils were investigated by me... To evaluate the current state of the environmental quality of agricultural soils in Taiyuan City, a hotspot for China's industrial development, the concentrations of 8 heavy metals in soils were investigated by means of extensive sampling in farmlands, forestlands,and grasslands in the city. Statistical analyses and spatial distribution maps were used to identify the most significant heavy metal pollutants. The mean concentrations of As, Cd, Cu, Hg, Pb, Zn, Ni, and Cr were slightly higher than their background values in Taiyuan's topsoil, but were lower than the maximum permissible concentrations in the Chinese Environmental Quality Standard for agricultural soils. Farmland soils in Taiyuan had the highest average Cd, Cu, Hg, Pb, Zn, and Cr concentrations, but the As and Ni concentrations did not differ significantly among the farmland, forestland, and grasslands. Soil contamination by Cd, Cu, Hg, Pb,Zn, and Cr was mainly derived from farming practices, especially the use of sewage water for irrigation. In contrast, As and Ni might derive mainly from the soil parent material. The identification of heavy metal sources in agricultural soils may provide a basis for taking appropriate action to protect soil quality. 展开更多
关键词 environmental pollution farming practices sewage irrigation soil parent material soil quality
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Contribution of Root Proliferation in Nutrient-Rich Soil Patches to Nutrient Uptake and Growth of Maize 被引量:19
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作者 LI Hong-Bo ZHANG Fu-Suo SHEN Jian-Bo 《Pedosphere》 SCIE CAS CSCD 2012年第6期776-784,共9页
Root proliferation can be stimulated in a heterogeneous nutrient patch; however, the functions of the root proliferation in the nutrient-rich soil patches are not fully understood. In the present study, a two-year fie... Root proliferation can be stimulated in a heterogeneous nutrient patch; however, the functions of the root proliferation in the nutrient-rich soil patches are not fully understood. In the present study, a two-year field experiment was conducted to examine the comparative effects of localized application of ammonium and phosphorus (P) at early or late stages on root growth, nutrient uptake, and biomass of maize (Zea mays L.) on a calcareous soil in an intensive farming system. Localized supply of ammonium and P had a more evident effect on shoot and root growth, and especially stimulated fine root development at the early seedling stage, with most of the maize roots being allocated to the nutrient-rich patch in the topsoil. Although localized ammonium and P supply at the late stage also enhanced the fine root growth, the plant roots in the patch accounted for a low proportion of the whole maize roots in the topsoil at the flowering stage. Compared with the early stage, fine root length in the short-lived nutrient patch decreased by 44%-62% and the shoot dry weight was not different between heterogeneous and homogeneous nutrient supply at the late growth stage. Localized supply of ammonium and P significantly increased N and P accumulation by maize at 35 and 47 days after sowing (DAS); however, no significant difference was found among the treatments at 82 DAS and the later growth stages. The increased nutrient uptake and plant growth was related to the higher proportion of root length in the localized nutrient-enriched patch. The results indicated that root proliferation in nutrient patches contributed more to maize growth and nutrient uptake at the early than late stages. 展开更多
关键词 biomass growth stage intensive farming system localized nutrient supply root length
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辽宁省淡水土著鱼类开发利用研究进展 被引量:18
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作者 骆小年 赵兴文 段友健 《大连海洋大学学报》 CAS CSCD 北大核心 2020年第2期155-160,共6页
辽宁省地处中国温水性鱼类和冷水性鱼类交汇过渡性质的区域,地理、气候环境和鱼类区系组成较特殊,出产许多特有的名特经济鱼类,为中国渔业经济发展做出了重大贡献。本文综述了辽宁省土著淡水鱼类资源特点、淡水土著鱼类开发历史及主要... 辽宁省地处中国温水性鱼类和冷水性鱼类交汇过渡性质的区域,地理、气候环境和鱼类区系组成较特殊,出产许多特有的名特经济鱼类,为中国渔业经济发展做出了重大贡献。本文综述了辽宁省土著淡水鱼类资源特点、淡水土著鱼类开发历史及主要经济鱼类的养殖状况,分析讨论了待开发土著鱼类的生物学特点,并针对辽宁省土著鱼类的开发利用,提出了宏观上围绕“调、育、赏”,微观上围绕“评、繁、养、推”的开发建议。 展开更多
关键词 辽宁省 土著鱼类 养殖 开发
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Spatial variations of macrozoobenthos and sediment nutrients in Lake Yangcheng: Emphasis on effect of pen culture of Chinese mitten crab 被引量:16
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作者 Liping Chen Ying Zhang +4 位作者 Qigen Liu Zhongjun Hu Yuejuan Sun Ziran Peng Lijing Chen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第11期118-129,共12页
We determined the effect of Chinese mitten crab(CMC) pen culture on the quantified spatial distribution of the macrozoobenthic community and sediment nutrients in Lake Yangcheng.Redundancy analysis indicated that wa... We determined the effect of Chinese mitten crab(CMC) pen culture on the quantified spatial distribution of the macrozoobenthic community and sediment nutrients in Lake Yangcheng.Redundancy analysis indicated that water temperature, macrophyte occurrence, sediment type, and crab culture were the main environmental factors that influence the spatiotemporal macrozoobenthic distribution. Macrozoobenthic assemblages in the lake were characterized by eutrophic indicator species. In the most polluted estuaries, the abundance and diversity indices of the whole community and abundance of chironomids and oligochaetes were significantly depressed, and sediment carbon(C) and phosphorus(P) were significantly enhanced compared with those in the western, middle(MB), and eastern basin(EB). Crab culture in this lake had significant effects on the species composition of the macrozoobenthic community in one of three CMC culture pens(CP), and generally depressed the abundance of most chironomid and oligochaete species. Significantly increased diversity, evenness, sediment carbon and nitrogen content, and sediment C:P ratio in the CP were found compared with those in the three basins.However, no conspicuous difference in sediment P content between the CP and the two basins of MB and EB was detected. Our results showed that the enhanced diversity and evenness of macrozoobenthos might be associated with the joint effect of macrophyte planting and crab predation, and macrophyte planting may modify the effects of CMC culture by leading to disproportional accumulation of C and N in the sediment relative to P in the CP of the lake. 展开更多
关键词 Lake Yangcheng Benthic macroinvertebrate Community structure Sediment nutrient Spatial distribution Pen farming
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补饲精料对西藏彭波半细毛羊羊肉品质的影响 被引量:17
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作者 金艳梅 武俊喜 +2 位作者 李鹏 吴洪新 张晓庆 《动物营养学报》 CAS CSCD 北大核心 2017年第2期562-570,共9页
本试验旨在研究补饲精料对西藏彭波半细毛羊羊肉品质的影响。选择30只成年彭波半细毛羊母羊,按照同质原则随机分为3组:放牧不补饲(对照,G1)组、补饲精料200 g/d(G2)组、补饲精料400 g/d(G3)组,每组10只。每天19:30补饲,正试期75 d。正... 本试验旨在研究补饲精料对西藏彭波半细毛羊羊肉品质的影响。选择30只成年彭波半细毛羊母羊,按照同质原则随机分为3组:放牧不补饲(对照,G1)组、补饲精料200 g/d(G2)组、补饲精料400 g/d(G3)组,每组10只。每天19:30补饲,正试期75 d。正试期结束屠宰,采集背最长肌测定营养物质含量和组织结构特征。结果表明:高水平补饲精料提高了母羊总干物质采食量,G3组平均日增重显著高于G1、G2组(P<0.05);补饲精料对羊肉p H1 h、p H24 h、滴水损失及水分和粗灰分含量无显著影响(P>0.05),但G3组的熟肉率,粗蛋白质、肌内脂肪含量,肌纤维密度显著高于G1组(P<0.05);G2、G3组羊肉总氨基酸、必需氨基酸和天冬氨酸含量显著高于G1组(P<0.05),G3组苯丙氨酸、赖氨酸含量显著高于G1组(P<0.05),G3组苏氨酸、谷氨酸含量有高于G1组的趋势(0.05≤P<0.10);补饲精料对羊肉饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸含量没有显著影响(P>0.05),G3组C18∶1 trans-9含量有低于G1组的趋势(0.05≤P<0.10)。上述结果表明,补饲精料能显著提高彭波半细毛羊羊肉营养价值,改善肉质嫩度,每只补饲400 g/d优于200 g/d。 展开更多
关键词 西藏彭波半细毛羊 放牧 补饲 肉品质 氨基酸 脂肪酸组分
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5°~25°坡耕地径流小区产流产沙规律 被引量:14
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作者 杨建霞 雷孝章 +1 位作者 邱景 陈平安 《中国水土保持科学》 CSCD 2008年第z1期30-34,53,共6页
基于四川省遂宁水土保持试验站坡耕地水土流失的观测数据统计,通过探讨降雨产生的地表径流深及冲刷量随坡度的变化,以及耕作措施和植被对坡面侵蚀的影响,提出坡耕地在降雨时的产流产沙规律:相同前提下,产流产沙量随坡度增加而增加;横坡... 基于四川省遂宁水土保持试验站坡耕地水土流失的观测数据统计,通过探讨降雨产生的地表径流深及冲刷量随坡度的变化,以及耕作措施和植被对坡面侵蚀的影响,提出坡耕地在降雨时的产流产沙规律:相同前提下,产流产沙量随坡度增加而增加;横坡耕作时,产流产沙量剧减,而顺坡耕作时产流产沙增加;种植农作物时,较之坡面植草,产流量减少,但产沙量增加。同时用灰色关联系数法确定各因子对坡耕地水土流失的影响序列为:产流时,坡度>耕作措施>植被;产沙时,耕作措施>坡度>植被。 展开更多
关键词 径流深 冲刷量 坡度 耕作方式 植被 因子组合 曲线突变
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