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Table of Content

    15 October 1964, Volume 30 Issue 4 Previous Issue    Next Issue
    THE INFLUENCE OF SEEDING DENSITY ON THE MICRQCLIMATE
    FUH BAW-PUH
    1964, 30 (4):  273-286.  doi: 10.11821/xb196404001
    Abstract ( )   PDF (836KB) ( )   Save
    On the bases of observation data from various sources of the influences of seeding density on the microdimate in analyses the crop have cover been The made main results are as follows: 1. Within the crop cover the decrease i}; radiation and temperature in the vege- tative period is proportional to the logarithm of seeding density. 2. The soil moisture and the relative humidity of the air in the crop cover decrease (the former) or increase (the later) lineally with the increase of density of seeding. 3. The variation of wind velocity with density of seeding can be expressed approxi-mutely by this equation: u=u0e-fN, where U signfies the wind velocity within the crop cover; U0 the velocity above the crop surface; N the density of seeding and f a parameter. 4. For each crop there is an optimum seeding density- that would lead to maximum yield.
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    THE WINTER AND SUMMER TEMPERATURE VARIATIONS AND FLUCTUATIONS OVER NORTHERN HEMISPHERE DURING THE LAST EIGHT DECADES
    TURN YUEH-WEI
    1964, 30 (4):  287-300.  doi: 10.11821/xb196404002
    Abstract ( )   PDF (731KB) ( )   Save
    A stuty has been made of the summer and winter temperature variations in vari-ous regions of the northern hemisphere during the years 1873-1950 with 10-year run-ning means as a measure of the secular changes. It leads to reveal that trends are dif-ferent with different regions. On 40°N, there has existed a general warming up, begin-ning in 1912 in winter (January) and in 1932 in summer (July); whereas no similar trend is discernible from the data and the departure curves constructed with them re-presenting temperature variations on 20°N since the commencement of the present cen-tury. It is noteworthy that increases in temperature are more pronounced in winter than in summer. This is a feature particularly marked in the Pacific and Atlantic sectors. In winter the correlation is十0.84 between Asia and Europe, but negative between Asia and North America. As regards the summer conditions, variations in Asia are better correlated with those in the Pacific and North :lmerica than with those in Europe, and negative correlations obtain in the case between Asia and Atlantic. A comparison of 10 year running means of January and July temperature diviations with pressure difference of latitudes 30°-50°N of corresponding regions has brought out that both agree in their directions of change, the correlation in Asia being in the neighbourhood of 十0.70. In Eastern Asia, increases in winter pressure ov,:r the continent, which may be considered as an indication of strong winter monsoon, are in general associated with colder winters;and a drop in summer pressure, probably a factor for stronger develop-ment of southeastern and southwestern monsoons, is usually accompanied with a rise in summer temperature.
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    A PRELIMINARY STUDY ON THE UTILIZATION OF RURAL LABOUR POWER IN THE YAO-TZE RICE AND COTTON AREA, CHEKIANG
    WANG SZU-CHUN
    1964, 30 (4):  331-343.  doi: 10.11821/xb196404005
    Abstract ( )   PDF (1030KB) ( )   Save
    The I'ao-tze rice and cotton area is situated in the northeastern pact of Chekiang Province. Its northern part was originally a shallow- marsh land along the coast of the Hongchow Bay. Through several centuries the inhabitants of the area have constructed artificial dikes around it and brought it under cultivation. The area has a very fertile soil, with rice and cotton as its main crops. Its population has increased rapidly, and both its rural and urban settlements are rather big in size. It is the most prosperous part of Chckiang Province. The utilization of the rural labour power was irrational in the past. Since the founding of the people's communes, there has been development of mechanization of farming, extension of multiple cropping area, and promotion of diversified econom)一Throughout the area, the landscape is characterized by the most intensive land utiliza-tion. Through organizing the collective economy, the communes employ the rural labour power rationally and ensure a continued rise in the people's living standard. Because of the difference in the rate of attendance between busy and slack farming seasons, the communes also make a rational deployment of rural labuuc power for the purpose of the integration of work and rest. Although the density of the peasant population in the area as a vyhulc is high, strik-ina differentiation is also evident in its various parts. The density figures in the northern part exceed those in the southern purr. The highest may be tm times the lowesr. Thus, rhere is a tendency of migration of population within the area.
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    A PRELIMINARY STUDY ON THE COMPILATION OF COUNTY AGRICULTURAL MAPS—WITH THE WORK IN THE CHUNG SHAN HSIEN, KWANGTUNG PROVINCE AN EXAMPLE
    H.K.MIAO, W.C.CHEN, K.Y.HUANG, C.Y.WAM, H.C.LIN, Y.G.TING, T.L.TOM
    1964, 30 (4):  344-358.  doi: 10.11821/xb196404006
    Abstract ( )   PDF (1128KB) ( )   Save
    In compiling hsien agricultural maps, the following principles should be observed: 1. The contents of each map should be closely related to the needs of agricultural production; 2. The achievements in the construction for water control and utilization and in the agricultural production after liberation in the hsien should be shown on the maps; 3. A series of maps depicting the physical conditions, agricultural economy and agricultural technics of the county should be included; 4. The geographical characteristics of the district concerned should be revealed; 5. All the maps in the series should be in harmony with each other, with respect to their contents, scales and legends. The basic subjects selected are:administrative division, agricultural land types, soil, natural calamities, construction for water control and utilization, agricultural labour, land utilization and agricultural regions. A scale of 1:5OOO0 or 1:100000 is appropriate with the case of Chung Shan in the compilation work. The cartographers must co-operate with the geographers, agriculturists, and hsien cadress. Both field study and office editing are requisite and full use should b} mode of tO}Opr`}lphical maps and aerial photographs.
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