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Table of Content

    25 June 1998, Volume 13 Issue 2 Previous Issue    Next Issue
    Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    ANALYSIS OF AGRO ECOLOGICAL ENVIRONMENTALFACTORS ON THE CAUSES FOR HIGH YIELD WHEAT IN QINGHAI XIZANG PLATEAU
    YU Chaoqing, ZHANG Yiguang, lin Zhonghui, Liu Yunfen
    1998, 13 (2):  97-103.  doi: 10.11849/zrzyxb.1998.02.001
    Abstract ( )   PDF (323KB) ( )   Save
    Qinghai Xizang Plateau is a high yield wheat area, and the highest yield of wheat can reach 15 2t/ha. Reasons accountable for high yield according to traditional concept are: (a)plentiful solar radiation; (b)great temperature range; (c)high intensity of photosynthesis of wheat; and (d)low consumption rate of respiration, which are thoughyt to be favorable for more accumulation of assimilation pro ducts in this area. However, experimental studies show that the mean rate of dry matters accumulation of wheat is a slightly lower than plain areas and traditional points can not explain this explicitly. Actually, because of low CO2 density in the plateau region, the efficiency of wheat leaf photosynthesis is just about 2/3 that of plain areas. Yet the high solar radiation and advantageous wheat community structure can make up deficiency of CO2 to some extent, so the mean rate of accumulation in the plateau region is just a slightly lower than plain areas. On the other hand, the annual average temperature is low in the plateau region which can elongate the duration of wheat growth greatly. So wheat has long time to take advantage of all the agro ecological conditions. The two factors, a slightly lower rate of dry matters accumulation and much longer duration of growing season, decide high product of dry matters in the plateau region. High harvest index wheat in the plateau region can get unusual high yield product.
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    A STUDY ON THE RELATIONSHIP BETWEEN CLIMATIC CHARACTERISTICS OF CORN YIELD OF GANSU AND OLR OF CHINA
    HAN Yongxiang, LI Dongliang, GUO Hui
    1998, 13 (2):  104-109.  doi: 10.11849/zrzyxb.1998.02.002
    Abstract ( )   PDF (221KB) ( )   Save
    In this paper,the climate related corn yield in 55 stations in Gansu province is resolved by means of EOF and REOF. According to the analysis of loading vecter, southeast Gansu is of most representative in corn yield. Furthermore,the climate related corn yield areas can be divided into 5 natural climatic zones:Eastern Gansu, Southern Gansu,Middle and Humid Mountain Area,Arid Mountain Area and Western Irrigated Agricultural Areas of Gansu.The first main component of the climate related corn yield can represent the temporal tendency of the climate related corn yield of Gansu.It is well correlated to the OLR in May and September of the same year.
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    EFFECTS OF WILD PLANT SAPS ON CROPS NUTRITION
    WANG Zhengyin, LI Liantie, WANG Yongde, YAO Wei, DUAN Donghua
    1998, 13 (2):  111-115.  doi: 10.11849/zrzyxb.1998.02.003
    Abstract ( )   PDF (202KB) ( )   Save
    The study area abounds with wild plant resources which may supply sufficient nutrive materials to crops for they contain many active organic materials, nutritious matter and mineral elements. However, several wild plants were only utilized as green manure in the past, therefore a great deal of natural plant resources have been wasted greatly. Objectives of this study were to evaluate the nutrition effects of saps in three wild plants, i.e Galium L.(A), Sambucus L.(B) and Coryza Less (C) on gram and maize at different concentrations (0, 1∶30, 1∶60, 1∶90) in pot culture experiment, and obtain new resources of plant nutrition and some important information for extensive utilization of wild plant resources in China. Results indicated that obvious stimulation of gram and maize plant height by sap A related to high levels of ZT and GA3 in the sap, and improvement of gram plant growth by sap C was due to high concentration of N, P and K in the sap. The increase of gram above ground and root dry weight by sap C was greater than that of maize by sap A and C, dry weight of gram plant was diminished by sap B and A at high concentration (1∶30). Sap B and C enhanced the activity of crop roots which amounted to 88.7%~213 2% for maize, and to 25 4%~110 2% for gram. It showed that there was a coincidence with high levels of Zn and IAA in sap B as well as high concentration of inorganic nutrient (N, P, K and Cu) in sap C. Except B 1∶30 treatment, the others raised the activity of catalase in maize plant, but there was little change to that of gram plant, showing the same change tendency in root activity of the two crops. Wild plant sap decreased total content of maize chlorophyll, whereas it increased total content of chlorophyll to 15 5%~38.5% and the content of chlorophyll b to 16.5%~50 5%. The obvious increase in content of P, total P uptake in gram plant and the content of K, total K uptake in maize plant by saps of the three wild plants indicated the existence of the differences of the two crop species in ultizing the nutrient in soil and wild plant sap under soil culture conditions.
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    A STUDY ON EMERGY EVALUATION AND SUSTAINABLEDEVELOPMENT OF TIBETAN ECO ECONOMIC SYSTEM
    YAN Maochao, HTOdum
    1998, 13 (2):  117-125.  doi: 10.11849/zrzyxb.1998.02.004
    Abstract ( )   PDF (208KB) ( )   Save
    Emergy is an alternative measure of value, based on real contributions to system performance, it is a new concept which quantifies “energy memory” in pro ducts and process. It is a new accounting unit of total contributions, direct and indirect, used in generation of a product or service. An emergy analysis of Tibetan system of economy and nature was performed in order to study its sustainability and emergy use. Indices of thermodynamic and economic vitality of Tibet were evaluated and a comparison with indices of other developed and developing countries or areas was performed.
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    A STUDY ON SOME PROBLEMS CONCERNING THE EXPLOITATIONAND MANAGEMENT OF MINERAL RESOURCES
    WANG Yunjia
    1998, 13 (2):  126-132.  doi: 10.11849/zrzyxb.1998.02.005
    Abstract ( )   PDF (306KB) ( )   Save
    By using the methods of theoretical analysis and practical calculation, this paper deals with the relationships between compensational exploitation and mineral resources conservation, the determination of the approved mining recovery rate and the actual mining recovery rate, the evaluation of the rational development and utilization of mineral resources as well as the determination of the coerctive mining recovery rate , and puts forward some suggestions to promote the protection and rational development of mineral resources.Researches have indicated that compensational exploitation could effectively prevent mineral resources from being wasted, but may not fully ensure their rational development and utilization. The management of mineral resources should adopt a mode featuring both compensation and supervision. The standard of approved mining recovery rate should not give way to mining methods, instead, major considerations should be given to the mineral resources conditions, which could be determined by establishing a statistical model. The actual recovery rate could be promptly and accurately determined by geographic information system and some other techniques. It is necessary and possible to impose restrictions on the utilization of mining methods featuring low recovery rate by putting into use the coercive mining recovery rate.
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    THE MINERAL BASE FOR CHINA'S SUSTAINABLE DEVELOPMENT
    ZHANG Lei
    1998, 13 (2):  133-138.  doi: 10.11849/zrzyxb.1998.02.006
    Abstract ( )   PDF (196KB) ( )   Save
    Although China is one of the largest mineral producers and consumers in the world, the country still has a poorer image in mineral resources due to a rapidly growing industrialization and a great number of population. To pursuit the goal of a sustainable development, it is very important for China to pour more capital and technologies into mineral industry for reinforcing its mineral base and to improve regulations and management in mineral production and consumption for protecting its limited mineral resources continually on the one hand, and to open more widely to the world's mineral market in order to increase imports of some key minerals such as oil and gas on the other. In terms of the practices of the world's industrialization and the recent economic development of China itself, the higher speed of economic development and the higher living standard a country has, the more opening mineral supply it depends while the deteriorated environment has a greater pressure on the structural change of energy consumption. China, therefore, has an urgent need for changing its mineral supply policy from a self reliance one to a new one which rests on “ two wheels ” of mineral supply from both domestic and international markets to drive its economy now, and such a policy should become a critical part of the national sustainable development strategy.
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    RISK MANAGEMENT OF A WATER SUPPLY SYSTEMDURING DROUGHT PERIOD
    FENG Ping
    1998, 13 (2):  139-144.  doi: 10.11849/zrzyxb.1998.02.007
    Abstract ( )   PDF (227KB) ( )   Save
    In this paper, risk theory has been used in the management of water resources during drought period, and the corresponding indexes such as risk, reliability, resiliency and vulnerability have been given. In practice, these risk indexes can reflect the real detrimental level of drought from different aspeects.The method is simpler than system optimization, and is more convenient for water resources administrator to formulate and choice effective measures for drought management. This study can provide a new way for planning and management of water resources.
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    INTEGRATED ACCOUNTING BETWEEN NATURALRESOURCES AND ECONOMY——ON 93'SNA AND SEEA
    LEI Ming
    1998, 13 (2):  146-153.  doi: 10.11849/zrzyxb.1998.02.008
    Abstract ( )   PDF (353KB) ( )   Save
    In order to build up Chinese System of Integrated Accounts between Natural Resources and Economy, an overall examination of the United Nations' New System of National Accounts (93'SNA) and Integrated Environmental and Economic Accounting (SEEA) is carried out in this paper, which include comments of the system of central framework and satellite framework in 93SNA, analysis of goals of accounting, rules and methods of accounting of SEEA and the differences of accounting between the central framework in SNA and SEEA.
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    RESOURCES AND THEIR SUSTAINABLE EXPLOITATIONIN GULF AREAS OF ZHEJIANG PROVINCE
    LI Zhibin, Bao Haosheng
    1998, 13 (2):  154-161.  doi: 10.11849/zrzyxb.1998.02.009
    Abstract ( )   PDF (140KB) ( )   Save
    Abstract Gulf area concentrated by marine resources serves as a base for seawater aquiculture, ocean resources exploitation and ocean industrial development. Three main semi closed gulfs, Xiangshan gulf, Sanmen gulf and Leqing gulf in Zhejiang Province have four superiority resources: (a) abundant marine living resources with annual average bioma 76.57g/m2 and 558.9/m2 of perch density in intertidal zone of gulfs. There are 124 species of fish, 30 species of shrimp, and 49 species of crab. Hydrologic environment of gulfs is suitable for breeding shellfish and seawater aquiculture. (b) Tidal flat area of 687.2km2 or 38.21% of the total three gulf areas. Of which tidal flat in middle and low tidal zone constitudes the majority, occupying 90 2%. (c) Great tidal range with tidal energy gradually becoming larger from mouth to top of the gulfs. The largest tidal range is distributed in Leqing gulf with average tidal range being 4 2m, and the largest, 8 43m. There are many islands in the mouth of the three gulfs which are favorable for the construction of tidal power stations. (d) Gulf surrounded by mountains from three sides. There are many natural harbours in the three gulfs such as Jiantiao harbour in Sanmen gulf and Damaiyu harbour in Leqing gulf.Resources in gulf area are veried. They are concentrated in distribution but interdependent and interactive. Exploitation of resources must follow with two principles:(a)comprehensive development dominated by exploitation of superiority resources; and (b)ecological economy.
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    A STUDY OF EVALUATION OF ARGRICUTURALLAND PRICE IN KORLA
    CHEN Fu, LIU Wei, WANG Tiewei, PENG Buzhuo
    1998, 13 (2):  163-168.  doi: 10.11849/zrzyxb.1998.02.010
    Abstract ( )   PDF (307KB) ( )   Save
    The paper focuses on the topic of how to choose correct methods and resolve a concrete calculation according to the characteristics of agricultural land. It is the key on how to make balance when calculating the profit produced from different crops. According to the practice in the research about agricultural land grading in Korla of Xinjiang, we set up an integration of agricultural land price system, which provides an example for future work.
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    AN ANALYSIS OF EFFECTS OF ARTIFICIAL NEURALNETWORK STRUCTURES ON PRECISION OFSTREAM FLOW FORECASTING
    FENG Guozhang, Li Peicheng
    1998, 13 (2):  169-174.  doi: 10.11849/zrzyxb.1998.02.011
    Abstract ( )   PDF (209KB) ( )   Save
    A stream flow forecasting model of feed forward multi layer artificial neural network(ANN), in which current precipitation and antecedent flow are considered as the model inputs according to runoff generation mechanism, is introduced. The deterministic coefficient is adopted as a norm to control ANN training error and precision of model calibration and verification. It is shown through the study that ANN training error is decreased and the coefficient of model calibration is increased, and meanwhile the coefficient of model verification is persistently decreased, with increase of complexity of ANN structures. It is also recognized that the key factor affecting the model precision is the number of neurons in the input layer, i e., the number of flow effecting factors. A method to select models for operational application, and to combine optimal forecasting ranges is proposed.
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    A STUDY ON DENSITY OPTIMUM CONTROL DURING STAND MANAGEMENT FOR PLANTATION
    WU Chengzhen, HONG Wei
    1998, 13 (2):  175-180.  doi: 10.11849/zrzyxb.1998.02.012
    Abstract ( )   PDF (197KB) ( )   Save
    Based on density decision model of plantation established by continuous stages dynamic programming, Genetic Algorithm is presented to select optimal decision in determining thinning age, and cutting age during stand management.The mathematical models and concrete method are offered and discussed.The density optimal projection of Chinese fir plantation during its management shows that Genetic Algorithm can get satisfactory results.The optimized results indicate that the optimal frequency of thinning is 2 for Chinese fir plantation during its management. The first time for thinning can be 11~12 years, while the second time for thinning can be 15~18 years. The optimal time for final cutting is 25 years.
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    A TENTATIVE STUDY OF CO2 EMISSION FROM FARMLANDSOIL IN TIBETAN PLATEAU
    LIU Yunfen
    1998, 13 (2):  181-186.  doi: 10.11849/zrzyxb.1998.02.013
    Abstract ( )   PDF (361KB) ( )   Save
    Experimental studies at the Lhasa agroecological station of the Chinese Academy of Sciences during growth seasons of 1995~1996 indicated that the CO2 emission flux of soil in the farmland and pasture land in Tibetan Plateau was 1 7~10 5kgCO2ha-2h-1(1 6~6 6μmol CO2m-2s-1). CO2 emission flux of soil under several vegetation covers during daytime is higher than that at night, and afternoon higher than the morning. During the growth period of crops and herbage, the CO2 emission amount in the farmland is about of that absorbed by plant photosynthesis. As raw materials for photosynthesis, the soil emitted CO2 forms organic matter for the plants, acting as carbon fixation. CO2 emission amount can not lead to CO2 concentration increase in the atmosphere. Factors affecting CO2 emission flux of soil are mainly the factors of growth period, vegetation type and environment. In terms of environmental factor, the CO2 emission flux of soil in the farmland is positively correlated with air and soil temperature (soil surface temperature at 0cm,land underground temperature at the depth of 5cm and 10cm), and is negatively correlated with air pressure and atmospheric CO2 concentration.
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    EVALUATION ON WILD SOFT SHELLED TURTLE RESOURCESIN SHANXI PROVINCE AND ITS PROTECTION
    WANG Guangrong, MAO Hongbin
    1998, 13 (2):  187-191.  doi: 10.11849/zrzyxb.1998.02.014
    Abstract ( )   PDF (220KB) ( )   Save
    Comprehensive investigations on the distribution divisions and ranges, specific types and biological characters of wild soft shelled turtle resource were carried out in Shanxi Province. The reasons accountable for the resource growth and decline were analysed and the existing amount of the resource was estimated as well. On the basis of these, measures for propagation and protection of wild soft shelled turtles were pointed out.
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