Table of Content

25 March 1991, Volume 6 Issue 1 Previous Issue    Next Issue

Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS

EVALUATION OF THE WIND ENERGY RESOURCE ON THE SOUTHEAST COAST OF CHINA Meng Zhaohan, Xu Huan, Du Huizhu 1991, 6 (1):  1-12.  doi: 10.11849/zrzyxb.1991.01.001 Abstract ( )   PDF (510KB) ( )   Save On the basis of 1971-1980 wind speed data from 332 weather stations (158 of them are automatic recorders), calculations are made on the number of hours of the effective wind speed (3.5-20.4ms-1), the annual and monthly amount of wind energy, and the change regularities of the wind speed and the wind energy. Distribution maps are drawn for the annual effective wind energy and effective wind speed frequncy. according to these maps the regionalization of wind energy and its variation with height are proposed.Using the practical data about the wind energy, the relation between the wind energy and the energy output through a wind machine is explored, and there upon the value of the utilization of the wind energy resource is found out for irrigation and electricity generation in given areas.According to the conditions of the wind energy resource, environment, topography and underground water level, proposals are made on the proper choice of design wind speed to set up a network of wind machines to provide energy for local use. The prospects are found encouraging.Since the results presented have been verified with satisfaction, the paper may serve as a better reference for authories concerned to plan their work. Related Articles | Metrics

AN ANALYSIS ON THE AREAL PRODUCTION SYSTEM OF AGRICULTURE IN NORTHWEST SHANDONG PROVINCE Yao Jianqu, Jiang Dehua 1991, 6 (1):  13-21.  doi: 10.11849/zrzyxb.1991.01.002 Abstract ( )   PDF (551KB) ( )   Save On the basis of the principal component analysis, this paper deals mainly with the areal production system of agriculture in Northwest Shandong Province.The relative matrix, eigenvalues and principal components of the constitutional variables of the system are given in Table 2-4. The first principal component can symbolically be regarded as the "input-output principal component", the second one as the "plantation principal component", the third one as the "grain production principal component", and the fourth one as the "industry and sideline principal component".In order to reveal the areal differentiations of the agricultural system in Northwest Shandong Province, a classification of the areal system has been carried out (Fig. 1) according to the marks given by the first principal component of the different areal units (Table 5). Related Articles | Metrics

MODEL AND ANALYSIS OF THE NATURAL PRODUCTIVE POTENTIAL OF AGRICULTURE OF THE GUO RIVER WATERSHED IN NORTHERN ANHUI PROVINCE Shen Siyuan, Xi Chengfan 1991, 6 (1):  22-33.  doi: 10.11849/zrzyxb.1991.01.003 Abstract ( )   PDF (693KB) ( )   Save Based on the wheat-maize rotation system, compartment models of the effects of natural factors on plant growth and crop production are established. Then they are combined to form a natural productive potential model of agricultue. The output of the model shows that the potential crop yield in this region will be 14.12 tons/ha if soil conditions are improved. The present limitation of crop production is soil nutrients. The long-run limiting factors will be soil organic matter content and water supply. The problems related to soil and water resources in the region should be tackled in a comprehensive way and by stages. Related Articles | Metrics

THE BASIC CHARACTERISTICS OF THE BEACH RESOURCES OF THE THREE BIG LAKES IN THE MIDDLE-LOWER YANGTZE RIVER REGION AND THEIR EXPLOITATION AND UTILIZATION Dou Hongshen 1991, 6 (1):  34-44.  doi: 10.11849/zrzyxb.1991.01.004 Abstract ( )   PDF (716KB) ( )   Save The Dongting, Poyang and Taihu Lakes are the three big lakes in the middle-lower Yangtze River region. The sediment has been depositing in these lakes for a long time, with the result that the beaches of different sizes have been formed. The beach area of the Poyang Lake is the biggest, that of the Dongting Lake is the second, and that of the Taihu Lake is the Smallest. Their total area amounts to 5.272 square kilometres. The development degree of the beach is closely related to the input amount of the sediment entering the lakes, the change range of water level, and the reclamation by the human race. The development degree of the vegetation corresponds with that of the beaches. As to the regimen of the beaches of these lakes, there is always a seasonal change. The frequency and the lasting period of the beach exposure depend upon the beach hight, but the annual change ratio differs greatly from year to year.It is necessary to make a comprehensive plan for the exploitation and utilization of the beach resources of the three lakes. Related Articles | Metrics

ON THE RELATIONSHIP BETWEEN RAINFALL FACTORS AND SOIL EROSION Yao Zhijun, Liao Junguo, Chen Chuanyou 1991, 6 (1):  45-54.  doi: 10.11849/zrzyxb.1991.01.005 Abstract ( )   PDF (589KB) ( )   Save Soil erosion is a serious and widespread problem in China. In this paper we investigate the quantitative relationship between rainfall factors and soil loss in the mountainous area of southwestern China, based on the data of a field experiment. We find that single rainfall factor such as rainfall amount or rainfall intensity can not be generally accepted as the best index for soil loss. We propose a new index which is a combination of different rainfall parameters. The correlation analysis shows this index is highly correlated with soil loss. Related Articles | Metrics

THE MANGROVE AND THE ACID TIDAL FLAT SOIL Zhang Xiran, Luo Xuan, Chen Yanhua 1991, 6 (1):  55-62.  doi: 10.11849/zrzyxb.1991.01.006 Abstract ( )   PDF (374KB) ( )   Save The mangrove and the acid tidal flat soil constitute a common ecological system in the tropical and subtropical coasts of China. The areas of mangrove of China are about 2.3×103 ha. They have 38 species and 21 families. Their distribution gradually decreases from south to north. The leftover roots and leaves undergo decomposition to bring about acidification of soil after the mangrove dies. The main properties of the acid tidal flat soil are as follows:1. The soil texture is mainly middle loam to light clay with the physical clay (less than 0.02 mm in diameter) ranging from 30% to 82%;2. The total salt content is 0.3% to 4.2% and the content of SO42- is 0-6 meq/100 g to 18.4 meq/100g;3. The content of organic matter is 0.4% to 11.8%, the C/N ranges from 11.3 to 44.5, the nutrient of phosphorus is rather low, and the CEC ranges from 9.1 meq/100g to 17.6 meq/ 100g;4. The pH ranges from 3.0 to 6.9.The developmental models are mainly to plant rice and to develop aquiculture. In utilization the disadvantageous factors are prominent. The management practices are to demarcate the cutting areas, to set up the protection areas and to promote researches on the ecological system of mangrove. Related Articles | Metrics

A STUDY ON THE CLIMATIC-ECOLOGICAL RESOURCES SUITABILITY OF THE PANAX GINSENG CULTURE AND ITS GEOGRAPHIC DISTRIBUTION IN THE CHANGBAI MOUNTAINS AREA Ma Shuqing, Liang Honghai 1991, 6 (1):  63-70.  doi: 10.11849/zrzyxb.1991.01.007 Abstract ( )   PDF (520KB) ( )   Save In this paper, the climatic-ecological factors and their optimum indices having an effect on Panax ginseng yield are studied. The factors are annual mean temperature, annual mean rainfall, the mean temperature of the hotest month, annual mean air relative humidity, and the length of the frostless season. Their optimum indices are 2.6℃, 778.7mm, 19.6℃, 70.6%, and equal to or more than 145 days respectively. The dependent functions [μ(xi)] of the factors to the optimum indices are decided, and the regression model to describe the geographic distribution of the integrated climatic-ecological suitability is established. The geographicdistribution of the μ of various parts of the Changbai mountions area and the optimum culture elevation of Panax ginseng are analyzed according to the model and the geographic network method. And then five climatic-ecological area for the Panax ginseng culture are demarcated in the Changbai mountains area of eastern Jilin Province. They are the optimum area, the suitable area, the comparatively suitable area, the comparatively unsuitable area and the unsuitable area. Related Articles | Metrics

THE CHARACTERISTICS OF THE HUMID PERIOD AND THE RATIONAL LAYOUT OF THE AGRICULTURAL PRODUCTION IN THE LOESS PLATEAU Wang Ling, Ni Jianhua 1991, 6 (1):  71-79.  doi: 10.11849/zrzyxb.1991.01.008 Abstract ( )   PDF (620KB) ( )   Save In this paper the data on the humid period and its parameters are used to assess the agricultural production of the Loess plateau.The mean humid period (G) and its coefficient of variation (C) and aridity index (A) are related to the cropping system and the risk level of agricultural production.The mean wet (W) and dry (D) spells within the humid period and their standard variations (α,β) are related to the possible drought and water-logging disasters.The above-mentioned parameters can be also used to assess the agricultural climatic environment and the agricultural production potential of the Loess Plateau. Related Articles | Metrics

A STUDY ON THE ESTIMATION METHOD OF THE PRODU CTIVITY OF THE WINTER WHEAT Wu Lianhai, Han Xiangling 1991, 6 (1):  80-87.  doi: 10.11849/zrzyxb.1991.01.009 Abstract ( )   PDF (501KB) ( )   Save In this paper, on the basis of summing up the works of previous researchers, we re-clarify the concept of crop productivity, put forth that the productivity contains many levels and that each level represents different productivity and has different limiting factors, and give a de-fination to each level. Proceeding from the atmosphere-crop-soil system, we probe into the relation between the growth, development and yield of the winter wheat on one hand and the environmental factors and the energy input on the other. Adopting the method which combines the dynamic simulation with the statistic analysis and making use of the d BASE-Ⅲ and BASIC languages, we set up the dynamic simulation software of the growth, development and productivity formation. of the winter wheat. The software can calculate the dry matter accumulation and the leaf index of the winter wheat and the soil moisture balance in different regions according to different needs. It can also calculate the productivity of each level. Related Articles | Metrics

RATIONAL EXPLOITATION AND UTILIZATION OF THE DEEPWATER COASTLINE RESOURCES IN NORTHERN ZHE JIANG Shi Xianhu, Huang Yong 1991, 6 (1):  88-96.  doi: 10.11849/zrzyxb.1991.01.010 Abstract ( )   PDF (627KB) ( )   Save The deepwater coastline resources in Northern Zhejiang are situated in the central section Of the- coastline of China. It includes two parts: One is called the Ningbo-Zhoushan coastline, which is in Ningbo Municipality and Zhoushan Archipelago. The other is called the Zhapu-Dushan coastline, which is in Jiaxing Municipality.The length of the Ningbo-Zhoushan coastline is 88 km in all. The coastline surrounds an extensive sea area but leaves several deep-water sea-lanes- The sea area possesses many superior points such as deepwater, calm sea, little deposit, no freeze, and so on. In the coastal areas of China, there are few other 'deepwater coastlines as good as the Ningbo-Zhoushan coastline. Although the Zhapu-Dushan coastline has disadvantages, it is 22 km long and near Shanghai. Moreover, its sea-lanes are superior to those of the Yangtze River Mouth.The article deals with the urgency, goal, and steps of exploitation of the deepwater coastline resources, based on the analyses of the present situation and trend of international and internal economy, trade, harbour, and sea transportation.Finally, it puts forward several proposals on rational exploitation of the deepwater coastline. Related Articles | Metrics