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    1997年, 第7卷, 第4期 刊出日期:1997-12-20 上一期    下一期
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    论文
    VULNERABILITY AND ADAPTATION OF CHINESE AGRICULTURE TO GLOBAL CLIMATE CHANGE
    蔡运龙
    1997 (4):  289-301. 
    摘要 ( 1105 )   PDF(610KB) ( 729 )  

    Global climate change is now widely recognized, although some uncertainties remain. Being sensitive to climatic conditions, agriculture will be influenced by climatic changes. The major effects can be generalized as changes in the geographical limits to agriculture, changes in crop yields and impacts on agricultural systems. Chinese agriculture is particularly sensitive to climatic change and variability. Given prospects for huge population increase and the already intense utilization of resources, there is a serious threat to China's abilily to feed itself. Thus, adaptation and adjustment to climatic change are urgently in need of attention. Climate is inherently variable and uncertain. so researchers should recognize this reality of climate in assessing implication for agriculture. A variety of approaches are suggested to reduce food production's when appraising the effect of climate change on vulnerability to climate.

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    MODELING OF REGIONAL DIFFERENTIATION OFLAND-USE DEGREE IN CHINA
    庄大方, 刘纪远
    1997 (4):  302-309. 
    摘要 ( 696 )   PDF(239KB) ( 761 )  

    This paper presents an index system and a method for calculating the comprehensive index of land-use degree. The latest data form two projects titled "Remote sensing Macro Investigation and Dynamic Study of National Resources and Environment" and "Resources and Environment Database of China" have been fully applied. In addition, this paper analyzes the regularity of the regional differentiation of land-use degree in China and the socio-economic and physical factors which affect the change of land-use degree in China. The "polar" model and the "longitude-distance" model of land-use degree of China are also developed.

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    DISTRIBUTION OF THE MAIN CROP GERMPLASM RESOURCES IN CHINA
    曹永生, 张贤珍, 白建军, 龚高法
    1997 (4):  310-316. 
    摘要 ( 1077 )   PDF(2552KB) ( 728 )  

    This paper describes the characteristics and rules of geographical distribution of main crop germplasm resources, totally 194 634 accesions of germplasm of 73 crops. Among them, food crop germplasm have 161 574 accesions, making up 83% of the total number. The maps of germplasm graphical distribution of main food crops, fibre plants and oil crops are presented. The crop germplasm in China are distributed widely in the whole country. With regard to provinces, crop germplasm resources are more bountiful in Shanxi, Guangxi, Sichuan, Shandong, Yunnan, Shaanxi, Hebei,Henan, Guangdong and the total germplasm resources in these provinces are 112 185 accessions,making up 57.6% in the whole country. With regard to agricultural ragions, crop germplasm resources at the middle and lower reaches of the Huanghe (Yellow) River are the most bountiful, which have 52 325 accessions, making up 26.9% in the whale country. The number of crop germplasm per million mu (1 ha = 15mu) of cultivated land is obviously different in different regions. The more bountiful the heat resources, the heat resources, the more complicated the terrain and the longer the history of agricultural planting, the richer the crop germplasm races per million mu cultivated land will be.

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    THE FEATURES OF SEA-ICE COVER, SNOW DISTRIBUTION AND ITS DENSIFICATION IN THE CENTRAL ARCTIC OCEAN
    效存德, 秦大河, 任贾文
    1997 (4):  317-327. 
    摘要 ( 679 )   PDF(293KB) ( 769 )  

    Based on the observation of sea-ice cover and measurement of snow depths and stratigraphy during China's First North Pole Sientific Expedition, three types of surface topography of sea ice and correspondingly three categories of snow distribution in the central Arctic are classified. It is considered that the classification will help to determine the sites for snow depth measurement, stratigraphy Observation and snowpits sampling. The snow cover is slowly accumulated during the long Arctic winter, approximately from September to early May next year, while its ablation shows abrupt from south to north. By the end of August, the snow cover is alment totally removed. The spatial distribution of snow depth is characterized by a northwardly decreasing trend, which is proposed to result from the remote vapour sources, i. e., the major vapour over the Arctic regions is transported from mid-latitudes. The stratigraphy of the snompits are characterized by the extensively existed depth hoar at the deeper part of the pits, which is probably a signal of the beginning of the long Arctic winter.The present of infiltration-congelation ice adhering to sea ice surface at the end of the ablation indicates that the annual accumulation is approximately equals to the annual ablation near north pole.

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    VARIATION OF d δ18O/dT IN PRECIPITATION IN THE QINGHAI-XIZANG PLATEAU
    章新平
    1997 (4):  328-338. 
    摘要 ( 671 )   PDF(2531KB) ( 754 )  

    The relations between δ18O and temperature on the different time scales were analysed,according to the data from Tuotuohe (34°13'N, 96°25'E; 4533 m a. s. l. ), Delingha (37°22'N,97°22'E; 2981 m a. s. l. ) and Xining (36°37'N, 101°46'E; 2261 m a. s. l. ) in the Qnghai-Xizang Plateau. The results show that the significance of d δ18O/dT on different time scales are different.The d δ18O/dT on the synoptic scale reflects the interdependent relation between δ18O and temperature in the short-term synoptic scale process; the d δ18O/d T on the seasonal scale reflects the relation between them whithin a year; and the d δ18O/d T on the climatic scale reflects the relation between them in the long-term climatic change. The calculated d δ18O/dT on climatic scale is very close to the theoretical values on the condition of advection transport for Tuotuohe Station. However, there are great differences between the calculated and the theoretical values for Delingha and Xining stations.

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    LOCATIONAL DISTRIBUTION AND SPATIAL DIFFUSION OF FOREIGN DIRECT INVESTMENTS FROM HONGKONG AND MACAO IN MAINLAND OF CHINA
    贺灿飞, 陈颖, 周颖
    1997 (4):  339-346. 
    摘要 ( 776 )   PDF(485KB) ( 723 )  

    Foreign direct investments (or FDIs) have been employed since the early 1980s and they have become more and more immportant in Chinese economic development. However, the roles of FDIs are very different between regions, partly due to the different locational preference of various source countries. Some facts show that FDIs from Hongkong - Macao indicate a strong locational preference. Therefore, this paper attempts to make an empirical research on the locational preference of Hongkong - Macao's FDIs and their spatial diffusion under the support of statistical data with regrereion analysis. In this paper, three statistical models, including the special location model, the general location model and the spatial diffusion model, are created. The results show that this kind of analysis is successful. The major conclusions are as follows. (1) The optimum location for FDIs from Hongkong - Macao lies in the coastal area, especially Guangdong, Hainan, Jiangsu, Shandong, Fujian provinces. Besides, Hubei Province is also an important radon. (2) The FDIs from HongkongMacao in China have diffused gradually from the coastal provinces to the inland regions, the northem and the metropolis and from the locations that had attracted a large number of investments to their vicinities since the 1990s. (3) The special location factors, such as the herder effect, the unique social and kinship ties are the key factors determining the special locational distribution. (4) The general location and spatial diffusion of Hongkong - Macao's FDIs are the results of interplay of several economic factors. They are the economic scale and advantage, the growth rate, the laier force and economic extrovert etc.

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    SUSTAINABLE EXPLOITATION AND UTILIZATION OF WATER RESOURCES IN THE INLAND RIVER BASIN OF ARID NORTHWEST CHINA
    马金珠
    1997 (4):  347-351. 
    摘要 ( 751 )   PDF(213KB) ( 718 )  

    Calculated in terms of surface runoff plus irrepeated groundwater, there is about 8.67 ×1010m3 of total available water resources in the inland river basins of arid Northwest China. Water resources is the decisive factor for survival of oases and human being. But there have arisen several aspects of Serious eco-environment problems resulted from irrational exploitation and utilization. From now on, the development and utilization of water not only requires to promote regional economy, but also needs to protect and improve the environment based on their potential. Sustainable utilization needs to broaden new sources and saving water at first. Then three measures are recommended.

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    STUDY ON BUSINESS POLLUTION AND ITS COUNTERMEASURES IN SHANGHAI
    杨凯, 王云, 甘湘南, 顾频
    1997 (4):  352-360. 
    摘要 ( 822 )   PDF(2513KB) ( 1014 )  

    Over the past ten years, Shanghai has experienced a pened of industrial restructuring and the economic development. The proportion of tertiary industry output in Shanghai's gross domestic production (GDP) is continuously rising. However, the rapid growth of tertiary industry has caused me adverse environmental effects, which, to a certain extent, have become the main reasons responsible for urban environmental deterioration and resident's complaints of their ambient environment. Based on the current investigation on the wide variety of business pollution in Shanghai, this paper analyzes the major problems existing in the environmental management of the tertiary industry,and discusses the factors and methods of assessment, and the ways of management and control.

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    STUDY ON EVAPORATION OF BIELAHONG RIVER BASIN
    崔丽娟
    1997 (4):  361-367. 
    摘要 ( 704 )   PDF(2514KB) ( 666 )  

    The Bielahong River is a typical marsh river whose hydrological characteristics the hydroledcal characteristics that of the whole Sanjiang Plain. Evaporation is an important element in water cycle which demonstrates water output. The paper gives the annual evaporation of the basin; calculates the evaporation coefficient in summer and the coefficient between marsh evaporation and pure water evaporation; analyses the ratios of evaporation to precipitation and to runoff; at last the paper reaches a conclusion that in years with different precipitation the effects of marsh on runoff are different.

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    BIOGEOCHEMICAL MECHANISM OF POSTDEPOSITIONAL MIGRATION OF Fe AND Mn IN LAKE AHA, CHINA
    万曦, 万国江, 黄荣贵, 普勇
    1997 (4):  368-374. 
    摘要 ( 636 )   PDF(2491KB) ( 818 )  

    Lake Aha in Guizhou Province, China is a medium-sized artificial reservoir with seasonally anoxic hypolimnion. Long-term sedimentary accumulation of iron and manganese resulted in their enrichment in the upper sediments. In anoxic season, Fe2+ and Mn2+ formed from bioledcal oxidation, would diffuse upto upper water from sediments. However, the concentration of Fe2+ incrlater and decreased earlier than that of Mn2+. Generally, Sulfate reduction occUrred at 6cm below the sediment-water interface. Whereas, in anoxic season, the reduction reached sediment top, inhibiting the release of Fe2+. As the oxidation of Mn2+ required molecular oxygen as catalyst, Serious anoxia caused the violent diffusion of Mn2+. Based on the bio-effects on the accumulation of Mn in natural fresh water, it's necessary to seek a way to control manganese rerelease through accumulated manganese bacteria action.Keywrods: petdeopitional migration of Fe and Mn, biogaxhemical effect, Lake Aha

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    ENVIRONMENTAL CHANGES SINCE LATE PLEISTOCENE IN ESTUARINE PLAIN OF JIULONG RIVER, FUJIAN PROVINCE
    陈文瑞, 蓝东兆, 陈承惠, 朱大奎
    1997 (4):  375-382. 
    摘要 ( 665 )   PDF(2442KB) ( 726 )  

    Based on the evidences of lithostratigraphy, palynology, micropaleontolopy and geochronology, paleoenvironments since the Late Pleistocene in the study area have been reconstructed. One of the most important inferences is that two marine transgressions have occurred, one in Wurm Sub-interglacial and the other Postglacial. The former had caused the study area to be in an estuary-bay envirment over the transgression maximum, with a sea level of no less than 10 m below present; foe latter reached its maximum over the Atlantic stage, with sedimentary environments of estuary-bay, hay or shallow sea, and the sea level arrived at the highest elevation in about 6 - 5 ka B.P. Furthermore, it is notable that, during the Late Wurm Glacial, the study area area had principally been in an estuary-bay environment, although the climate, like many other areas, turned cold and dry, It reflects a general trend of crustal subduction in Jiulong Estudrine Plain over this pened.

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