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"Three-in-One" Ecological Development and Efficient Utilization Model of Aggregates
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作者 Yunkai FAN Shichang XU +2 位作者 Qiangjie HUANG Yiyuan LU Ziyi WEI 《Asian Agricultural Research》 2024年第6期13-18,共6页
Green mining and the formation of an effective and efficient development model have become key issues that aggregates enterprises around the world need to solve urgently.On the basis of analyzing the development statu... Green mining and the formation of an effective and efficient development model have become key issues that aggregates enterprises around the world need to solve urgently.On the basis of analyzing the development status of aggregates industry in Xiluodu area,the paper studied the main problems faced in the construction of green aggregates mines at present,and proposed a"three-in-one"ecological,intelligent and efficient green mine construction model for"ecological development","green logistics"and"solid waste recycling"of aggregates.The study has certain theoretical value and practical significance for the construction of green aggregates mine in Xiluodu area. 展开更多
关键词 AGGREGATES ECOLOGICAL development EFFICIENT utilization
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Research Progress on the Development and Utilization of Proteins in Edible Insects
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作者 冉文波 赵晨霞 《Agricultural Science & Technology》 CAS 2014年第4期683-687,共5页
The recent progress on the proteins in edible insects was summarized, in- cluding the nutritional value, healthy value, food safety, extraction and content mea- surement of the proteins in edible insects, as well as t... The recent progress on the proteins in edible insects was summarized, in- cluding the nutritional value, healthy value, food safety, extraction and content mea- surement of the proteins in edible insects, as well as the main development direc- tion of edible insect proteins. And we also pointed out the bottlenecks that restricted the development and utilization of proteins in edible insects, and proposed the prospect of the research, development and utilization of edible insects proteins. 展开更多
关键词 Edible insects PROTEIN Research progress development and utilization
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Development and Utilization of the World's and China's Bulk Mineral Resources and their Supply and Demand Situation in the Next Twenty Years 被引量:9
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作者 ZHANG Zhaozhi JIANG Guangyu +1 位作者 WANG Xianwei ZHANG Jianfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第4期1370-1417,共48页
Bulk mineral resources of iron ores, copper ores, bauxite, lead ores, zinc ores and potassium salt play a pivotal role on the world's and China's economic development. This study analyzed and predicted their resourc... Bulk mineral resources of iron ores, copper ores, bauxite, lead ores, zinc ores and potassium salt play a pivotal role on the world's and China's economic development. This study analyzed and predicted their resources base and potential, development and utilization and their world's and China's supply and demand situation in the future 20 years. The supply and demand of these six bulk mineral products are generally balanced, with a slight surplus, which will guarantee the stability of the international mineral commodity market supply. The six mineral resources (especially iron ores and copper ores) are abundant and have a great potential, and their development and utilization scale will gradually increase. Till the end of 2014, the reserve- production ratio of iron, copper, bauxite, lead, zinc ores and potassium salt was 95 years, 42 years, 100 years, 17 years, 37 years and 170 years, respectively. Except lead ores, the other five types all have reserve-production ratio exceeding 20 years, indicative of a high resources guarantee degree. If the utilization of recycled metals is counted in, the supply of the world's six mineral products will exceed the demand in the future twenty years. In 2015-2035, the supply of iron ores, refined copper, primary aluminum, refined lead, zinc and potassium salt will exceed their demand by 0.4-0.7 billion tons (Gt), 5.0-6.0 million tons (Mt), 1.1-8.9 Mt, 1.0-2.0 Mt, 1.2-2.0 Mt and 4.8-5.6 Mt, respectively. It is predicted that there is no problem with the supply side of bulk mineral products such as iron ores, but local or structural shortage may occur because of geopolitics, monopoly control, resources nationalism and trade friction. Affected by China's compressed industrialized development model, the demand of iron ores (crude steel), potassium salt, refined lead, refined copper, bauxite (primary aluminum) and zinc will gradually reach their peak in advance. The demand peak of iron ores (crude steel) will reach around 2015, 2016 for potassium salt, 2020 for refined lead, 2021 for bauxite (primary aluminum), 2022 for refined copper and 2023 for zinc. China's demand for iron ores (crude steel), bauxite (primary aluminum) and zinc in the future 20 years will decline among the world's demand, while that for refined copper, refined lead and potassium salt will slightly increase. The demand for bulk mineral products still remains high. In 2015-2035, China's accumulative demand for iron ores (crude steel) will be 20.313 Gt (13.429 Gt), 0.304 Gt for refined copper, 2.466 Gt (0.616 Gt) of bauxite (primary aluminum), 0.102 Gt of refined lead, 0.138 Gt of zinc and 0.157 Gt of potassium salt, and they account for the world's YOY (YOY) accumulative demand of 35.17%, 51.09%, 48.47%, 46.62%, 43.95% and 21.84%, respectively. This proportion is 49.40%, 102.52%, 87.44%, 105.65%, 93.62% and 106.49% of that in 2014, respectively. From the supply side of China's bulk mineral resources, it is forecasted that the accumulative supply of primary (mine) mineral products in 2015-2035 is 4.046 Gt of iron ores, 0.591 Gt of copper, 1.129 Gt of bauxite, 63.661 Mt of (mine) lead, 0.109 Gt of (mine) zinc and 0.128 Gt of potassium salt, which accounts for 8.82%, 13.92%, 26.67%, 47.09%, 33.04% and 15.56% of the world's predicted YOY production, respectively. With the rapid increase in the smelting capacity of iron and steel and alumina, the rate of capacity utilization for crude steel, refined copper, alumina, primary aluminum and refined lead in 2014 was 72.13%, 83.63%, 74.45%, 70.76% and 72.22%, respectively. During 2000-2014, the rate of capacity utilization for China's crude steel and refined copper showed a generally fluctuating decrease, which leads to an insufficient supply of primary mineral products. It is forecasted that the supply insufficiency of iron ores in 2015-2035 is 17.44 Gt, 0.245 Gt of copper in copper concentrates, 1.337 Gt of bauxite, 38.44 Mt of lead in lead concentrates and 29.19 Mt of zinc in zinc concentrates. China has gradually raised the utilization of recycled metals, which has mitigated the insufficient supply of primary metal products to some extent. It is forecasted that in 2015-2035 the accumulative utilization amount of steel scrap (iron ores) is 3.27 Gt (5.08 Gt), 70.312 Mt of recycled copper, 0.2 Gt of recycled aluminum, 48 Mt of recycled lead and 7.7 Mt of recycled zinc. The analysis on the supply and demand situation of China's bulk mineral resources in 2015-2035 suggests that the supply-demand contradiction for these six types of mineral products will decrease, indicative of a generally declining external dependency. If the use of recycled metal amount is counted in, the external dependency of China's iron, copper, bauxite, lead, zinc and potassium salt will be 79%, 65%, 26%, 8%, 16% and 18% in 2014, respectively. It is predicted that this external dependency will decrease to 62%, 64%, 20%, -0.93%, 16% and 14% in 2020, respectively, showing an overall decreasing trend. We propose the following suggestions correspondingly. (1) The demand peak of China's crude steel and potassium salt will reach during 2015-2023 in succession. Mining transformation should be planned and deployed in advance to deal with the arrival of this demand peak. (2) The supply-demand contradiction of China's bulk mineral resources will mitigate in the future 20 years, and the external dependency will decrease accordingly. It is suggested to adjust the mineral resources management policies according to different minerals and regions, and regulate the exploration and development activities. (3) China should further establish and improve the forced mechanism of resolving the smelting overcapacity of steel, refined copper, primary aluminum, lead and zinc to really achieve the goal of "reducing excess production capacity". (4) In accordance with the national strategic deployment of "One Belt One Road", China should encourage the excess capacity of steel, copper, alumina and primary aluminum enterprises to transfer to those countries or areas with abundant resources, high energy matching degree and relatively excellent infrastructure. Based on the national conditions, mining condition and geopolitics of the resources countries, we will gradually build steel, copper, aluminum and lead-zinc smelting bases, and potash processing and production bases, which will promote the excess capacity to transfer to the overseas orderly. (5) It is proposed to strengthen the planning and management of renewable resources recycling and to construct industrial base of renewable metal recycling. (6) China should promote the comprehensive development and utilization of paragenetic and associated mineral species to further improve the comprehensive utilization of bulk mineral resources. 展开更多
关键词 China bulk scarce mineral resource development and utilization demand prediction supply and demand analysis reducing excess production capacity
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THE UTILIZATION OF WATER RESOURCE AND THE OASIS ECONOMIC DEVELOPMENT IN ARID LAND—A CASE STUDY OF TURPAN BASIN 被引量:1
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作者 Fu Xiaofeng Department of Urban and Resource Sciences, Nanjing University, Nanjing 210093 People’s Republic of China 《Journal of Geographical Sciences》 SCIE CSCD 1997年第2期60-68,共9页
Turpan Basin is a unique geographic region in China. The topography of the Basin is closed and the climate is extremely dry. The shortage of water resource has been restricting the existence and development of the oas... Turpan Basin is a unique geographic region in China. The topography of the Basin is closed and the climate is extremely dry. The shortage of water resource has been restricting the existence and development of the oasis in Turpan Basin. This paper briefly analyzes the characteristics of the basin's water resources, and expounds the processes of their utilization and regional development. It points out that the exploration of water resource is close to the limit and the utilization of water resource is unreasonable. So it is nonrealistic to follow the traditional exploration pattern. According to the transforming pattern between runoff and groundwater in the basin, an overall planning of the utilization of the water resource is advanced. Based on the relation between the maintenance of Aydingkol Lake and the existence of the oasis, the amount of water resource used must be controlled in order to guarantee the existence of the lake. The orientation of the utilization of water resource is to improve the management level of water resource, and to apply advanced water saving technology. Building up an economic system which can effectively use water resource is the orientation of the oasis sustainable economic development. 展开更多
关键词 Turpan Basin water resource utilization oasis economic development.
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Further development and sustainable utilization mode of grassland tourism resources: a case study of Inner Mongolia Autonomous Region, China 被引量:3
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作者 Liu Min Liu Aili Chen Tian 《Ecological Economy》 2007年第2期190-201,共12页
Tourism resources are important foundation for the development of tourism industry.Grassland is not only a kind of important resource but also a great attraction to visitors.Therefore,the integrated development and su... Tourism resources are important foundation for the development of tourism industry.Grassland is not only a kind of important resource but also a great attraction to visitors.Therefore,the integrated development and sustainable utilization of grassland tourism resources are of great significance.This paper,based on the analysis of literatures and the current problems existing in grassland tourism,summarizes the speciality of grassland tourism development,deals nation as example and carries out empirical research.Based on the status quo of grassland tourism resources in Inner Mongolia,this study analyzes the characteristics of grassland tourism resources,the necessity and feasibility of integrated development,then proposes the following suggestions: idea for development,mode of development,regional cooperation,tourism products development,especially the three modes of development based on the resources conditions - the mode of relying on market,the mode of combination aggregation and the mode of relying on quality. 展开更多
关键词 Grassland tourism resources Integrated development Sustainable utilization Inner Mongolia autonomous region
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Study on the Impact of Climatic and Environmental Factors on the Development and Utilization of Rooftop Solar Energy Resources in Inner Mongolia
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作者 Li Xinghua Hu Yanan +1 位作者 Zhao Jiaqi Hao Yuzhu 《Meteorological and Environmental Research》 CAS 2019年第6期32-36,共5页
Based on the data of 8 solar radiation stations and 119 meteorological stations in Inner Mongolia from 1961 to 2017 as well as the comparative observation of rooftop solar distributed photovoltaic power generation equ... Based on the data of 8 solar radiation stations and 119 meteorological stations in Inner Mongolia from 1961 to 2017 as well as the comparative observation of rooftop solar distributed photovoltaic power generation equipment,the impact of climatic and environmental factors on the development and utilization of rooftop solar energy resources was studied.The results show that the main climatic factors affecting rooftop solar power generation were cloud cover,precipitation,relative humidity,visibility,gale,dust weather,temperature and lightning disaster.Except for temperature and lightning disaster,other meteorological elements were negatively correlated with rooftop solar power generation,namely reducing direct radiation.The high temperature in Inner Mongolia in summer could cause the solar cell efficiency to decrease by 40%-60%,while the low temperature in eastern region in winter was not suitable for the development of rooftop solar energy resources.Lightning is the main meteorological disaster affecting the safe operation of photovoltaic systems,and class-2 lightning protection equipment needs to be installed.Photovoltaic power generation equipment should be installed on a roof which is not covered by high buildings and on the windward side of a chimney as much as possible.Areas with heavy dust pollution need to remove dust on the surface of solar panels in time.Snow and ice should be removed timely during snowfall in winter. 展开更多
关键词 SOLAR radiation SOLAR energy METEOROLOGICAL FACTORS Environmental FACTORS development and utilization
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Development and Utilization of Rural Idle Homesteads in the Context of Rural Revitalization——A Case Study of Leisure Agriculture
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作者 Dingpu LIU 《Asian Agricultural Research》 2019年第2期53-56,共4页
The existence of a large number of idle homesteads in rural areas not only causes waste of land resources,but also injures farmers' property rights and hinders the implementation of rural revitalization strategy. ... The existence of a large number of idle homesteads in rural areas not only causes waste of land resources,but also injures farmers' property rights and hinders the implementation of rural revitalization strategy. The emergence and vigorous development of rural leisure agriculture provides a new way of utilization and method for the development and utilization of rural homesteads. From the perspective of leisure agriculture,this paper analyzed the characteristics,advantages and disadvantages of the overall development model of rural idle homestead,farmstay model and characteristic industry development model,and discussed the actual case to enrich the research on the development and utilization of idle homestead. It pointed out that there are problems such as insufficient tourism resources and single management content,lack of legal basis for revitalizing the homestead,lagging reform of rural land property rights system,and difficulty in expanding the space for leisure tourism development in the process of developing rural idle homestead. It is recommended to provide reference for the effective improvement of the efficiency of idle homestead utilization,increase farmers' income,and promote the rural revitalization strategy. 展开更多
关键词 RURAL REVITALIZATION RURAL IDLE HOMESTEAD development and utilization LEISURE AGRICULTURE
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Protection, Development and Utilization of Industrial Heritage Under the Background of Transformation of Exhausted Cities: A Case Study of Construction Planning of Anyuan National Mine Park
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作者 LENG Haoran NI Shaomin CHEN Sihua 《Journal of Landscape Research》 2019年第5期9-12,共4页
Firstly,the status quo of Pingxiang City as a resource-exhausted city was introduced firstly,and then the development situation of Anyuan Coal Mine,which is the representative of traditional coal industry in Pingxiang... Firstly,the status quo of Pingxiang City as a resource-exhausted city was introduced firstly,and then the development situation of Anyuan Coal Mine,which is the representative of traditional coal industry in Pingxiang,was summarized.Moreover,the classification and value of mining heritage were analyzed,and it is proposed that the development of mine heritage tourism and urban transformation should be combined.The planning of Anyuan National Mine Park under the background of urban transformation was analyzed to provides an idea for the protection and utilization of industrial heritage. 展开更多
关键词 EXHAUSTED CITIES Industrial HERITAGE PROTECTION development and utilization Anyuan NATIONAL Mine PARK
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Resource Utilization Pattern and Development in Hills——A Case for the Pindar Basin of Garhwal Himalaya, India
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作者 Vishwambhar Prasad Sati 《Journal of Mountain Science》 SCIE CSCD 2004年第2期155-165,共11页
Agrarian system is well adapted in Himalayan eco-system. Hence, the people have adopted the traditional subsistence cereal farming and it becomes the main stay of Himalayan people. About 80 percent of the workable for... Agrarian system is well adapted in Himalayan eco-system. Hence, the people have adopted the traditional subsistence cereal farming and it becomes the main stay of Himalayan people. About 80 percent of the workable force is attached with agriculture and its allied practices, according to the census of 1991. Although, horticultural farming runs parallel with agriculture, its proportion in terms of land is quite less, resulted in a negligible place in the economy of the region. Human resources, mainly men are attached with national security after recruitment in Army. While, women play a vital and integrated role in maintaining the workable potential in the field of agriculture and are known as backbone of economy. An animal resource implies foremost and wider part in agricultural system and economy as well. Water resources are unutilized yet, while almost all the major rivers of our country are originated from and flowing through this region. Increasing population causes forest resources depletion. The economy of the region is rested either on 憈raditional cereal farming?or 憁oney order based?development, which could not take place due to its remoteness from the main streams of the country. The impact of modern technology with innovation in agricultural system remains impracticable due to unwillingness of people in one hand and on the other hand, adverse geographical conditions like topography, climate etc. which could not permit the uses of modern innovation in the field of agriculture. As for infra-structurally,this region is lacked behind, due to its inaccessibility. While, this region is bestowed with numerous rivers, many places for tourists and pilgrims, and huge forest resources. They might be used evenly in the development processes. The practice of tourism will help for the further development, particularly, in the wake of the newly born state, Uttaranchal. The present paper aims to evaluate the present potentiality of resources and their balanced utilization in the Pindar Basin. A precise study has been done on resource utilization, ecology and environment with keeping view in mind that more or less exploitation of resources could not influence the environment and the economy of the region. 展开更多
关键词 Agrarian system Himalayan eco-system cereal farming ecologically fragile zones money order based resource utilization alpine meadows sustainable development ecology and environment
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Establish Green Industry System,Improve the Comprehensive Utilization Level of Salt Lake Resources,and Create A New Pattern of Green Sustainable Development in Qaidam Basin
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作者 XIE Yuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期439-439,共1页
Qaidam Basin in Qinghai Province has rich multiple complex resources with salt lakes as the core.These resources form a special condition for the development of green economy,having rare and particular nature.The
关键词 Establish Green Industry System Improve the Comprehensive utilization Level of Salt Lake Resources and Create A New Pattern of Green Sustainable development in Qaidam Basin
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The Development and Utilization of Red Cultural Resources
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作者 Honglan Liao 《Review of Educational Theory》 2020年第2期66-70,共5页
In recent years,red cultural resources,or visual,artifactual,institutional and other expressions of China’s revolutionary culture as well as the socialist culture fostered by the Chinese Communist Party since its fou... In recent years,red cultural resources,or visual,artifactual,institutional and other expressions of China’s revolutionary culture as well as the socialist culture fostered by the Chinese Communist Party since its founding,have been used to educate people,reduce poverty in older revolutionary areas where the resources are located,and enhance awareness of the practical utility of learning from history.At the same time,how best to develop and utilization red cultural resources has become a much-debated issue.In the context of this debate,a series of practical problems have emerged that urgently need to be solved.The present study argues that strengthening theoretical research;creating innovative infrastructural,technological,funding,and staffing solutions;improving institutional mechanisms;and strategically shaping the red brand will lead to a more rational and sustainable development of red cultural resources,maximizing their practical utility for Chinese society as a whole. 展开更多
关键词 Red culture Cultural resources development and utilization
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The analysis of the development and utilization of personnel archive information resources
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作者 He Li 《International Journal of Technology Management》 2013年第5期84-85,共2页
Navigated by the forces of the market economy mechanism, the development and utilization of human resources is key to guaranteeing the operation of public institutions .The personnel archive is a record of one's main... Navigated by the forces of the market economy mechanism, the development and utilization of human resources is key to guaranteeing the operation of public institutions .The personnel archive is a record of one's main experiences and performances, thus playing a vital role in the process of developing talents .This article mainly make an analysis of the main role and status of personnel archive information and the main means and contents of talents development. 展开更多
关键词 the information resources of personnel archive development utilization.
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The Plan for Development of Standards on the Utilization of Seawater lssued
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《China Standardization》 2006年第3期9-,共1页
关键词 the Plan for development of Standards on the utilization of Seawater lssued
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A Study on the Interest Linkage Mechanism of the Taxus Industry Chain in Pengshui Miao and Tujia Autonomous County
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作者 Zhengchun WANG Guifang CHEN +4 位作者 Haiyan JIANG Guohao ZHANG Yan TIAN Jing XIN Jihui LI 《Agricultural Biotechnology》 CAS 2023年第5期22-25,共4页
At the Taxus base of Pengshui Miao and Tujia Autonomous County,Chongqing,the comprehensive development and utilization of Taxus was carried out with seedling cultivation,understory economy,product processing,ecotouris... At the Taxus base of Pengshui Miao and Tujia Autonomous County,Chongqing,the comprehensive development and utilization of Taxus was carried out with seedling cultivation,understory economy,product processing,ecotourism and other aspects as the main line.The benefit linkage mechanism of the operation of the Taxus industrial chain was explored and analyzed,so as to extend and supplement the Taxus industrial chain.The two models of"company+farmer"and"company+village collective+farmer"are relatively close benefit linkage models,which indirectly promote the increase of farmers income and smoothly guarantee the operation of the industrial chain,thereby playing a positive role during the development of the Taxus industry.This study provides reliable countermeasures and suggestions for the sustained and healthy development of the Taxus industry in Pengshui County. 展开更多
关键词 TAXUS development and utilization Industrial chain Interest linkage Mechanism
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Harmonious Development of Utilization and Protection of Tidal Flats and Wetlands-A Case Study in Shanghai Area 被引量:3
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作者 陈吉余 程和琴 +1 位作者 戴志军 Doeke EISMA 《China Ocean Engineering》 SCIE EI 2008年第4期649-662,共14页
Spatial, environmental, and material resources are important for tidal flats and wetlands, thus, a harmonious balance between utilization and protection should be maintained. In the present study, the concept of tidal... Spatial, environmental, and material resources are important for tidal flats and wetlands, thus, a harmonious balance between utilization and protection should be maintained. In the present study, the concept of tidal flat is defined, and its spatial limitation is also clarified. Located at the Yangtze Estuary, tidal flats in Shanghai area are selected for study. The relationship between water discharge and sediment transport of the Yangtze River, allowed exploration intensity and needs for wetland protection are discussed in the paper. The dynamic process and changing trend for different types of tidal flats are illustrated in detail. Regulations are proposed for a reasonable exploitation, dynamic protection, and ecosystem restoration of each individual tidal fiat and wetland. Some valuable suggestions are put forward for further study about the sustain'able exploitation of offshore resources in Shanghai area. 展开更多
关键词 Shanghai area harmarious development utilization PROTECTION tidal fiat WETLand
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Exploitation of Wild Flowers and the Sustainable Development of Flowers Industry in China 被引量:4
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作者 HONG Li PANG Songling ZHUO Lihuan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第2期76-79,共4页
This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic res... This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic resources and the sustainable development of flowers and plants industry in China, and put forward some proposals on the existing question and the prospects for the development. 展开更多
关键词 wild flowers and plants development and utilization flowers and plants industry sustainable development
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Development and Utilization of Saline Lake Resources and Protection of Ecological Environment in Qaidam Basin in Qinghai Province 被引量:3
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作者 MENG Wei SHU Jianmin +1 位作者 YANG Rongjin LI Yanwu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期191-193,共3页
Qaidam basin is an important part of National Key Development Area–Lanzhou-Xining Area,is a key region of resource development in Western Development,is a National Circular Economy Pilot Zone.The focus of
关键词 saline lake resources development and utilization protection of ecological environment Qaidam Basin.
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Beneficial effects of a decreased meal frequency on nutrient utilization,secretion of luteinizing hormones and ovarian follicular development in gilts 被引量:1
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作者 Lun Hua Lianpeng Zhao +10 位作者 Zhengyu Mao Wentao Li Jing Li Xuemei Jiang Lianqiang Che Shengyu Xu Yan Lin Zhengfeng Fang Bin Feng De Wu Yong Zhuo 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第3期1098-1111,共14页
Background:Replacement gilts are typically fed ad libitum,whereas emerging evidence from human and rodent studies has revealed that time-restricted access to food has health benefits.The objective of this study was to... Background:Replacement gilts are typically fed ad libitum,whereas emerging evidence from human and rodent studies has revealed that time-restricted access to food has health benefits.The objective of this study was to investigate the effect of meal frequency on the metabolic status and ovarian follicular development in gilts.Methods:A total of 36 gilts(Landrace×Yorkshire)with an age of 150±3 d and a body weight of 77.6±3.8 kg were randomly allocated into one of three groups(n=12 in each group),and based on the group allocation,the gilts were fed at a frequency of one meal(T1),two meals(T2),or six meals per day(T6)for 14 consecutive weeks.The effects of the meal frequency on growth preference,nutrient utilization,short-chain fatty acid production by gut microbial,the post-meal dynamics in the metabolic status,reproductive hormone secretions,and ovarian follicular development in the gilts were measured.Results:The gilts in the T1 group presented a higher average daily gain(+48 g/d,P<0.05)and a higher body weight(+4.9 kg,P<0.05)than those in the T6 group.The meal frequency had no effect on the apparent digestibility of dry matter,crude protein,ether extract,ash,and gross energy,with the exception that the T1 gilts exhibited a greater NDF digestibility than the T6 gilts(P<0.05).The nitrogen balance analysis revealed that the T1 gilts presented decreased urine excretion of nitrogen(−8.17 g/d,P<0.05)and higher nitrogen retention(+9.81 g/d,P<0.05),and thus exhibited higher nitrogen utilization than the T6 gilts.The time-course dynamics of glucose,α-amino nitrogen,urea,lactate,and insulin levels in serum revealed that the T1 group exhibited higher utilization of nutrients after a meal than the T2 or T6 gilts.The T1 gilts also had a higher acetate content and SCFAs in feces than the T6 gilts(P<0.05).The age,body weight and backfat thickness of the gilts at first estrous expression were not affected by the meal frequency,but the gilts in the T1 group had higher levels of serum luteinizing hormone on the 18th day of the 3rd estrus cycle and 17β-estradiol,a larger number of growing follicles and corpora lutea,and higher mRNA expression levels of genes related to follicular development on the 19th day of the 3rd estrus cycle.Conclusions:The current findings revealed the benefits of a lower meal frequency equal feed intake on nutrient utilization and reproductive function in replacement gilts,and thus provide new insights into the nutritional strategy for replacement gilts,and the dietary pattern for other mammals,such as humans. 展开更多
关键词 GILTS Luteinizing hormone Meal frequency Nutrient utilization Ovarian follicular development
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Effect of dietary calcium or phosphorus deficiency on bone development and related calcium or phosphorus metabolic utilization parameters of broilers from 22 to 42 days of age 被引量:1
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作者 YANG Yun-feng XING Guan-zhong +5 位作者 LI Su-fen SHAO Yu-xin ZHANG Li-yang LU Lin LUO Xugang LIAO Xiu-dong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第11期2775-2783,共9页
This experiment was conducted to investigate the effect of dietary calcium(Ca)or phosphorus(P)deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age b... This experiment was conducted to investigate the effect of dietary calcium(Ca)or phosphorus(P)deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age based on our previous study,which indicated that dietary Ca or P deficiency impaired the bone development by regulating related Ca or P metabolic utilization parameters of broilers from 1 to 21 days of age.A total of 504 one-day-old Arbor Acres male broilers were randomly assigned to 1 of 4 treatments with 7 replicates in a completely randomized design,and fed the normal control and Ca-or P-deficient diets from 1 to 21 days of age.At 22 days of age,the broilers were further fed the normal control diet(0.90%Ca+0.35%non-phytate P(NPP)),the P-deficient diet(0.90%Ca+0.18%NPP),the Ca-deficient diet(0.30%Ca+0.35%NPP)or the Ca and P-deficient diet(0.30%Ca+0.18%NPP),respectively.The results showed that dietary Ca or P deficiency decreased(P<0.05)tibia bone mineral density(BMD),bone breaking strength(BBS),ash content,tibia ash Ca content and serum P content on days 28 and 42,but increased(P<0.05)tibia alkaline phosphatase(ALP)activity of broilers on day 42 compared with the control group.Furthermore,the broilers fed the P-deficient diet had the lowest(P<0.05)tibia BMD,BBS,ash content,serum P content and the highest(P<0.05)serum Ca content on day 28 compared with those fed the Ca-deficient or Ca and P-deficient diets.The results from the present study indicated that the bone development and related Ca or P metabolic utilization parameters of broilers were the most sensitive to dietary P deficiency,followed by dietary Ca deficiency or Ca and P-deficiency;dietary Ca or P deficiency impaired the bone development possibly by regulating serum Ca and P contents as well as tibia Ca content and ALP activity of broilers from 22 to 42 days of age. 展开更多
关键词 calcium deficiency phosphorus deficiency bone development metabolic utilization parameter BROILER
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Priority-sequence of mineral resources' development and utilization based on grey relational analysis method 被引量:3
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作者 Wang Ying Zhang Chang Jiang Gaopeng 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第3期395-400,共6页
Generally, the sequence decision of the development and utilization of Chinese mineral resources is based on national and provincial overall plan of the mineral resources. Such plan usually cannot reflect the relative... Generally, the sequence decision of the development and utilization of Chinese mineral resources is based on national and provincial overall plan of the mineral resources. Such plan usually cannot reflect the relative size of the suitability of the development and utilization of mineral resources. To solve the problem, the paper has selected the gift condition, the market condition, the technological condition,socio-economic condition and environmental condition as the starting-points to analyze the influential factors of the priority-sequence of mineral resources' development and utilization. The above 5 conditions are further specified into 9 evaluative indicators to establish an evaluation indicator system. At last,we propose a decision model of the priority sequence based on grey relational analysis method, and figure out the observation objects by the suitability index of development. Finally, the mineral resources of a certain province in China were analyzed as an example. The calculation results indicate that silver(2.0057), coal(1.9955), zinc(1.9442), cement limestone(1.9077), solvent limestone(1.5624) and other minerals in the province are suitable for development and utilization. 展开更多
关键词 Mineral resources development and utilization Priority-sequence Grey relational analysis method
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