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    Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    LIU Aimin, FENG Zhiming, LI Fei
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    At present, agriculture still belongs to high resources consumption low benefit type of agriculture in China. However, as agricultural natural resources are limited, high benefit utilization of agricultural resources must be achieved. Agricultural resources utilization models and mechanism transformation among deferent models are studied in this paper from mesoscopic regional point of view.Case analysis indicated that agricultural resources utilization models are in change process, and this process has distinct hierarchies ;material resources input level in the change process is added, agricultural resources utilization efficiency is increased;and agricultural resources utilization technology system adaptable to agricultural resources utilization model has diversity and hierarchies.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    PANG Huancheng, CHEN Fu
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    The three cropping patterns, i.e., winter wheat/spring corn/summer corn/autumn corn, winter wheat/spring corn/summer corn, and winter wheat summer corn, were analyzed from aspects of yield, resources utilization rate and economic benefit in the paper. The results showed that yield of all the three cropping patterns could surpass 15t/ha, indicating the reality of reaching 15t/ha in Huang Huai PLain under condition of intensive multiple cropping system. The yield differences among the three cropping patterns showed that intensive multiple cropping and reasonable adjustment techniques were effective ways to further increase field annual yield in this region. The highest yield of winter wheat/spring corn/summer corn/au tumn corn reached to 22.01t/ha, which was one of the effective cropping patterns to near or to top 22.50t/ha with present techniques. For cropping pattern of winter wheat/spring corn/summer corn/autumn corn, the key to yield increase was due tothe total ears added; the high assimilation rate could be maintained and light heat resources utilization rate could be increased by effective measures in combination with transplanting and other relevant practices. The economic benefit was reflected in high input/high output, but some indexes of output to input rate tended to be declining.Comprehensive judgment from the viewpoint of yield, net income, material expenses and labor employed indicated that winter wheat/spring corn/summer corn/autumncorn pattern had advantages in general.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    YANG Jianshe, XIN Naiquan
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    Based on analysis of agricultural resources characteristics in the simiarid loessal hilly and gully regions in Dingxi of Gansu Province, the paper focuses on the discussion of the establishment of resources saving agrotechnical systems, present sitcuation of their development, and role they play. Their sustainable development directions of the resource saving agrotechniques related to the water assemble techniques and water assemble irrigations are also stated in this paper, so as to promote the control bases for high efficient development of agriculture in areas similar to Dingxi.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    NI Jinren, YIN Kangqian, ZHAO Zhijie
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    So far, a number of wetland classification systems have been developed by investigators from different fields. However, general criteria or indexes for the classification are still needed, and quantitative models should be introduced for the purpose of organizing information and describing the similarities or differences among the elements in wetlands. Based on the systematic comparison of existing classification systems, a comprehensive classification system for wetlands is presented in this paper, from which identification at different levels (clan, sub clan, group, class and type) becomes much easier. “Clan” is determined by hydrologic and geomorphologic characteristics, which can be further divided into several “sub clans” according to dynamic controlling factors upon the wetlands; “group” is used for distinguishing the differences of bottom characteristics of wetlands; and “class” is defined in terms of vegetation physiogomy, followed by the more detailed description of “type” demonstrating the immersing features in the wetlands. Furthermore, the new classification system will promote the process of quantitative descriptions of wetland systems.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    PENG Xiyu, WANG Li
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    The way for spatial allocation of agricultural water resources is proposed with the concept of spot shadow price of irrigation system. Then certain problems on spatial allocation of water resources in China are discussed. Some results are given in this paper:The pricing system of agricultural water resources based on spot shadow price can raise utilization efficiency of water resources, attract input to irrigation system, and be helpful to form complete water market.Meanwhile, the pricing system, which is partly opposite to equity, needs to be adjusted in order to meet equitable objective.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    YU Dongsheng, SHI Xuezheng
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    In this paper, the annual aridity was calculated with Penman Evaporation Formula improved and revised in China. According to indexes of Chinese Soil Taxo nomy , the soil moisture regime was also estimated. Results show that 3 soil moisture regime districts and 6 sub districts can be divided tentatively in China.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    FENG Guanglong, LIU Changming
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    An experiment was conducted under continuous drying conditions in the field to examine root system growth in relation to water extraction pattern by winter wheat from 1995-1996 at Luancheng Experimental Station of Agricultural Ecosystems, Chinese Academy of Sciences which is located in the North China Plain. A model for analyzing the relationship between soil water extraction and root growth was put forward and verified. Extraction was analysed in terms of two components: (a) the time when the extraction front reaches a particular depth is defined as the moment when soil water content(θ) begins to decline exponentially with time, and (b) the decline of θ with time occurs at each depth after the extraction front arrives.Root length density declined gradually with depth, the period of fastest growth of root occurred after early head before anthesis and root length in each layer reached a maximum during flowering stage. The effect of soil water on root growth was little after anthesis, which implies that the depth and volume of soil water extraction by winter wheat mainly rely on the root length accumulation and downward penetraction during vegetative phase. The root front penetrated down to 100cm deep before jointing, thereafter the extraction and growth of root fronts descended together. Once the root front arrived at a given depth, root proliferation continued until about 40%-20% of extractable water in the layer remained. Although the maximal depth of root front penetration was up to 180cm, the ability of water uptake by root was strong and the amount of soil water available to winter wheat was much more in the lower layers, yet as the distribution amount of root system was too less that the extraction front could only arrive at 120cm, and most amount of water required by winter wheat come from 0-60cm layer.Under soil continuous drying condition, the deficiency of soil water was one of the important factors which restricted the ability of water extraction by root. The peak of extraction rate per unit root length (q) occurred near the beginning of extraction each layer. As soil dried, q declined substantially in approximate linear relationship with the fraction of extractable water (FEW) as FEW was more than 0.8.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    GUO Zhongwei, LI Dianmo, YU Dan
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    Ecosystem provides multiple benefits for human being, which can be considered as a type of natural resources. The valuation of natural resources is a key step toward their sustainable use. The major functions of the ecosystem, dominated by forests, are water and soil conservation and flow regulation in the catchments of the upper Yangtze River. This is a kind of indirect use value. The focus of paper is to estimate the ecosystem values relating to this aspect.Xingshan County is situated in the western part of Hubei Province. The Three Gorges Dam will be located to the east of the county. The Shennongjia natural protected area lies to the north. The thick forest covers an area of 94×104ha in the county with a coverage of 43.9 percent. The Xiangxi River and the Liangtai River in Xingshan collect 62 comparatively major streams and form two primary water drainages. Both flow into the Yangtze River. Because the benefit from flow ecosystem regulated cannot realize on the spot usually, the use values of the benefit may be transferred spatially by a certain of “passages”to attain to a place out of catchment that provides some suitable external conditions to realize their use values.In accordance with the transfer of value of biological resources spatially, the method of valuation of process benefit was adopted in the paper.The method emphasized quantitative analysis for the process of value rea lizing and the benefit resulting from the value.According to the types of vegetation, soil and slopes, the Xingshan County was divided into 90 types of polygons by means of GIS. The process of value of ecosystem regulated flow was analyzed and the capacity of flow regulation of polygons was determined. In the dry period (December to next April), the ecosystem can release about 150.04×106m3 of water, which can increase the flow of Yangtze River by about 19.3m3 /sec. In the flood period (July to September),it can intercept and contain about 324.77×106m3 of water, leading to a drop of the flow by about 41.77m3/sec. According to simulation models, the increase of 1m3/sec of flow can result in a power increase of 0.17kW at the Gezhouba Hydroelectric Power Plant in the dry period and the decrease of 1m3/sec of flow can make a power increase of 0.04kW in the flood period. The increment of output of Gezhouba Hydroelectric Power Plant by the ecosystem regulating flow was 38.5×106kW·h/a.By above analysis, it is known that the ultimate effect of the ecosystem regulated flow is the increment of output of a hydroelectric power plant. The value of the ecosystems regulating flow is 8.85×106RMB$/a in Xingshan County.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    NIE Xianzhong, ZHANG Jie, LU Shufei, TANG Jiafa
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    Domestic tourists'flow to Jiuzhaigou is expressed as the linear and sea sonal flow between several nodes.Based on case studies,this paper identifies some regularities:(a)Tourism image of the destination and tourists' preference are essential to their perception, cognition and decision; (b)Tourists' attributes (age, educational background,occupation and income,etc.) have effect on their preference and destination's decision; (c)The tourists' decisions are correlated with their economic ana lysis following their perception,preference,and motive; (d)The domestic tourists to Jiuzhaigou mainly select summer holiday and some festivals,which was the result of some causes.Then the peper emphasizes the importance of the image's decision of tourism destination.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WU Yuhua
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    Yintan National Tourism and Holiday Resort, located on the seashore of Beihai City of Southwest China, is one of the twelve national tourism and holiday resorts approved by the State Council in October of 1992. It occupies an area of 22.15 km2 and is divided into western part and eastern part by Fengjia River. The western part covers 8.71 km2. From 1987 up to now, the western part of Beihai Yintan National Tourism and Holiday Resort has been attracting more than 8 million tourists. The tourism activities bring in environmental problems, namely, natural resources destruction, visual pollution, pollution of waste water and trash, sand quality degradation and tourist overload.(a)Natural resources have been seriously destroyed. A lot of trees were cut away and the lands was used for dense buildings. Part of the beach is occupied by blocks of villas and tourism facilities. A wave proof dike separates the spacious beach into two zones, making the width of the beach from more than a thousand meters to less than two hundred meters.When the tide is at flood, the west section of the beach is submerged to the foot of the dike,reducing the bathing function of the section.(b)Many villas, hotels and tourism facilities do not harmonize with surroundings in aspects of location and shape. The varied buildings in the bathing center are established just next to the dike, too near to the beach and the sea, disordering the landscape of the water front. Buildings in other places are also too dense.People there would think they were in a downtown city. The space and design style of the entrance square are a failure, and it can not attract visitors to stay in.(c)Sea water near the seashore is polluted by nitrogen, BOD5 and oil.(d)The beach is polluted by waste water and trash from local domestic lifes and tourism activities, and the sands bagan to change from white color to gray.(e)The west section of the beach is often overloaded by tourists, for they crowd there to get convenient service.Those problems are derived from the lack of natural resources survey, weakplanning, poor management and insufficient investment to environment. So corres pondingly, the survey and evaluation of natural resources should be done first followed by environment releted planning and its implementation. The key is master plan which should include contents of environmental capacity, environmental protection, landscape control, landuse allocation,and distribution of tourism attractions. Finally,environmental policies and management measures should also be formulated and put to practice.They should contain the following: restriction of types and scale of projects, collection of pollution tax from hotels and restaurants, control of vehicles and parking lots, announcement of the state of environment, stipulation of tourists, clean of trash, relocation of service stands.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    CHEN Wenrui, ZHU Dakui
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    The Yangtze River Delta is one of the most developed areas in China, but the land area per capita is only 0.135 ha, and the cultivated land per capita is 0.045 ha, far less than 0.078 ha, the mean value of the whole country. Moreover, substantial cultivated land has been converted for other purposes, and soil has been polluted. As a result, land degradation occurred, some excellent land has been wasted with low utilization rate.In order to attain sustainable development, land resources must be sustainably used. First, as far as agricultural land is concerned, maintenance and utilization must be done in a combined way to improve the yields of cultivated land. Furthermore, land resources in the mountain areas must be comprehensively used, and the agricultural structure be readjusted. Second, as for land for non agricultural usage,urban land must be intensively utilized, the town and township enterprises and the villages be rationally planned and distributed, and the tourist land be well developed. Finally, but not least, the relationship between the agricultural and non agricultural land must be rationally readjusted.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    ZOU Lan
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    Production factors are moving westward from the coastal areas in China. As a result, M/A activities are increasing, beneficial to the check of the enlargement of regional gaps. The westward movement of the factors is caused by the overall rise of cost for the coastal enterprises which are labor intensive, high material and energy consuming. Public listed companies intend to expand towards inland areas.The regional imbalance is mainly caused by the price distortion under central planned economy practised from the 1950s through to 1992. Cheaper resources from Western China made the profits in coastal manufacturing sectors seemingly high. Therefore, after opening and reform in the late 1970s, favorable policies and priority investments were earmarked for coastal areas only, promoting the coastal development effectively as talents, capitals and know hows from all over the nation concentrated in East China, while depriving the development potentials of the inland areas. They were the negative incentives.State intervention in Western China's development is necessary, but not in a traditional sense. The state's role is to improve the infrastructures to facilitate the entry of the coastal investors and set up a favorable policy environment and a better legal framework to induce and protect the new investors. Meanwhile economic policies in Western China have to be readjusted to promote the growth of the non state sectors, which are dwarfed by the state sector.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    GAN Chunji, PENG Shiyao, SU Jinwei, ZHANG Jinbiao, ZHOU Biqing
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    The characteristics of Monascus pigments resources and the status of their applications were discribed. The authors reported the results in the research and the exploitation of Monascus pigments and their derivatives, and forecasted the future perspectives in serial products of Monascus pigments.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    ZHANG Changqin, FENG Baojun, LU Yuanlin, ZHOU Bing, GAO Lianming
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  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    ZHOU Guomo, Jin Chonghua, Zhang Weicheng, JIN Chong hua, ZHANG Wei cheng
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  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    SHI Qishun
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    The major gene means a single gene or locus, which has great effect on quantitative trait. It is of great significance to the fixation of the beneficiad genotype, marker assisted selection, marker assisted introgression , the transgenic technology applied to quantitative trait and a big increase in economic benefit.The conception, present condition of major genes research on livestock and poultry were expounded in this paper.It is proposed that the exploitation of genetic resources of livestock and poultry aims essentially at finding and using major genes of special characters. How to exploit and use the major genes of livestock and poultry has been approached.