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growth and
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  生长
     Study on MWECR CVD Deposition Technique and Growth and Properties of BN Films
     MWECR CVD系统及BN薄膜生长与特性研究
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     Study on the Effects of Enzyme Preparations and Amino Acid Chelated Salt on Pheasants Growth and Performance
     酶制剂、氨基酸螯合盐对环颈雉生长发育及生产性能影响的研究
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     Growth and Characterization of GaN and AIGaN by RFP-MBE
     GaN和AIGaN/GaN的RFP-MBE生长及其特性研究
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     Effects of Root Zone Temperature on Growth and Development and Physiological and Biochemical Metabolism of Cucumber in Solar Greenhouse
     根区温度对日光温室黄瓜生长发育和生理生化代谢的影响
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     Studies on the System Simulation for Potato Growth and Development
     马铃薯生长发育的动态模拟研究
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  增长
     The Research on Economic Growth and Income Distribution
     经济增长与收入分配问题研究
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     Open Society,Economic Growth and Pattern Choice of Capital Market Opening
     开放社会、经济增长与资本市场开放模式选择
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     A Spatial Econometrical Analysis on China's Economic Growth and Income Distribution Disparities
     中国经济增长与收入分配差异的空间统计分析
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     Study on Interactions between Economic Growth and Income Distribution
     经济增长与收入分配互动研究
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     A Study on the Growth and Efficiency of China's Service Industry
     中国服务业的增长与效率研究
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  “growth and”译为未确定词的双语例句
     Regulation of Growth and Promoter Activity from Type I Collagen by Cytokines and Drugs including Matrine in ECM Producing Cells
     细胞因子和苦参碱等药物对ECM产生细胞增殖和I型胶原启动子活性的调控
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     Study on the Growth and Incentive of Chinese Entrepreneur
     我国企业家成长与激励研究
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     STUDY ON A STRUCTURE-FUNCTION MODEL OF PLANT GROWTH AND ITS CALIBRATION
     植物生长的结构—功能模型及其校准研究
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     Studies on Industrial Growth and Industrial Investment Fund in the Period of Economic Transition in China
     经济转型期产业成长与产业投资基金研究
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     Growth and Development and Expression Analysis of Genes in Different Upland Rice Roots under Water Deficit
     水分亏缺条件下旱稻根系发生发育及相关基因的表达分析
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  growth and
We obtain some precise estimates of the order of growth and of the exponent of convergence of the zero-sequence of solutions for this equation.
      
The model has the unique optimal growth and an optimal rate of infrastructure allocation.
      
Relation between Growth and Vertical Distribution of Fine Roots and Soil Density in the Weibei Loess Plateau
      
The influence of woodland soil bulk density on the growth and distribution of fine root system of main planting tree species in the Weibei Loess Plateau was investigated by means of pot culture and field survey.
      
Bulk density of pot culture media had clear effects on the growth and development of P.
      
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This paper deals with ecology and part of the Life history of the Chinese alligator. In making the investigation, the auther has paid visits to the Lower Yangtze basin and its adjacent territory during February-October in 1951, 1954, and 1956 in south Anhwei.The Chinese alligator inhabits the alluvial plain. During the growth and development of river, there are two seasonal periods in a year. The rainy season covering from April to October, and the dry season from October to March of the next year. During...

This paper deals with ecology and part of the Life history of the Chinese alligator. In making the investigation, the auther has paid visits to the Lower Yangtze basin and its adjacent territory during February-October in 1951, 1954, and 1956 in south Anhwei.The Chinese alligator inhabits the alluvial plain. During the growth and development of river, there are two seasonal periods in a year. The rainy season covering from April to October, and the dry season from October to March of the next year. During the dry season, one side of a broad sand swamp is an artifial dam, while the opposite is the natural bank, which may be gradually destroyed by the current in the rainy season year after year.During the rainy season, the water level is higher which serve as a shelter to the hidden alligator.The Chinese alligator is not only found along the basin of the lower Yangtze River, but also in south Anhwei districts along Chin-I-Kiang and Cheun-Ho River system. The plain is always sunk down by the tide, its surface being usually covered by a harder mud. A lot of burrows are distributed here and there. Each burrow has seveal holes. It is seaier to find out such burrows in the fall and winter, because the reeds are then cropped.Investigations showed that there were two types of burrows with respect to the sex of the alligator found inside. The male burrow is a simple tunnel with two openings, while the female's is more complicated.A longitudinal section of the female's burrow shows that the burrow is somewhat like a three-storied building. The differences in the level of diggings are considered as adaptations to different water levels.The following table presents burrow types in sexual diamorphism.The changes of water levels of the alluvial plain of definite regional river system may be related, according to our field examination, to the period of the animal's hibernation. The burrowed creature is coiled underground in 2m. deep during the winter season. The types of the burrows may be shown in the following table:In the wet season, the water level is about 8m. deep, just reaching.the surface of plain. This fact indicates that water is essential to the animal in the regulation of its physiological processes.The alligator mates in May and June, nesting at the end of June, laying The words "Doors'' and "Windows" adopted here are taken to indicate the various openings of the nests of the alligators.eggs in the July and August. The eggs measure 59 mm. in diameter. The shell is very hard, being ashy white in colour.The head and body length of the breeding adults as well as the number of eggs found in females may be given in following table:Other observations on the night movement during the breeding period may be shown as follows:

1.我国古代早在商周时期,即对此项动物加以记载,下至晋唐,都曾有记述,包括分布、形态和生态诸方面。综合辨考前人记载鼍及其近种的分布,是在今日的湖北、山西、广西、广东、安徽、福建、江苏、江西和当时邻国柬埔寨等地。 2.动物的栖息地为河流、湖泊、丘陵山涧的河漫滩的芦苇及竹林丛中。调查地包括了安徽省、江西省沿江的河漫滩及属於黄山天目山的青弋江、渲河、青山河的下游和芜湖、南陵、宣城、泾县、当涂、高淳、宁国、郎溪诸县。时间是1951年,1954年,1956年2—10月间。 3.据据39尾鼍的标本测定,其雌雄的外形性徵差异不显著,但其所营穴窟却有显著的两性相异形式。二者均包括有洞身和各种不同的洞口,适於进出、呼吸等用。 4.雌性个体异穴分居。 5.动物每年4月初开始出洞活动,6月间配偶,7月初至8月中旬筑巢产卵,在在6—8月间最为活动,10月下旬开始入蛰休眠。 6.动物在竹林芦苇田中筑巢,取材枯叶、杂草、乾枯稻草和菱白叶。体长92.1厘米者,巢中的卵数20。卵长59毫米,径34毫米,围110毫米,卵重43克,壳重3.75克。 7.动物昼伏夜出,风雨之夜概不出洞。最热季节,日中当大气气温31—35℃、湿度40—48°时,曝...

1.我国古代早在商周时期,即对此项动物加以记载,下至晋唐,都曾有记述,包括分布、形态和生态诸方面。综合辨考前人记载鼍及其近种的分布,是在今日的湖北、山西、广西、广东、安徽、福建、江苏、江西和当时邻国柬埔寨等地。 2.动物的栖息地为河流、湖泊、丘陵山涧的河漫滩的芦苇及竹林丛中。调查地包括了安徽省、江西省沿江的河漫滩及属於黄山天目山的青弋江、渲河、青山河的下游和芜湖、南陵、宣城、泾县、当涂、高淳、宁国、郎溪诸县。时间是1951年,1954年,1956年2—10月间。 3.据据39尾鼍的标本测定,其雌雄的外形性徵差异不显著,但其所营穴窟却有显著的两性相异形式。二者均包括有洞身和各种不同的洞口,适於进出、呼吸等用。 4.雌性个体异穴分居。 5.动物每年4月初开始出洞活动,6月间配偶,7月初至8月中旬筑巢产卵,在在6—8月间最为活动,10月下旬开始入蛰休眠。 6.动物在竹林芦苇田中筑巢,取材枯叶、杂草、乾枯稻草和菱白叶。体长92.1厘米者,巢中的卵数20。卵长59毫米,径34毫米,围110毫米,卵重43克,壳重3.75克。 7.动物昼伏夜出,风雨之夜概不出洞。最热季节,日中当大气气温31—35℃、湿度40—48°时,曝晒於水面。

The city of Lanehow lies in the central part of China in latitude approximate 36°03′north, longitude 103°57'east, at elevation 1,508.53 M. Kowlanshan, the area surveyed, being one of the many loess plateau hills surrounding Lanchow, situates on the southeastern suburb of the city. Physiographically, the area is a part of the dissected loess plateau with an altitude of 1,508-2100 M. Owing to the influences of the geographical condition and high elevation, the climate of this area is of continental climatic type....

The city of Lanehow lies in the central part of China in latitude approximate 36°03′north, longitude 103°57'east, at elevation 1,508.53 M. Kowlanshan, the area surveyed, being one of the many loess plateau hills surrounding Lanchow, situates on the southeastern suburb of the city. Physiographically, the area is a part of the dissected loess plateau with an altitude of 1,508-2100 M. Owing to the influences of the geographical condition and high elevation, the climate of this area is of continental climatic type. The mean annual precipitation is 338.6mm. with 61.1% of it falling in June, July and August, annual mean temperature, 6.9℃., relative humidity, 58%, annual total evaporation, 3,571mm. and annual mean wind velocity 5.8m/sec. The upper portion of the hill is entirely covered with a thick layer of loess and underneath lies the red earth of the tertiary period. As a result of that, soils in the area surveyed, which has been developed from the loess, is high in calcium content. It belongs to the chestnut soil type with a PH value between 7.6 and 8.1. The vegetation of this area shows the following ecological characteristics: 1) The specific composition of the plant is rather scanty with about. 124 speeies belonging to 93 genera and 41 families; 2) The vegetation bears a simple physiognomy. No natural growth arbor been found in the whole area during the period of investigation, though a few species of cultivated trees are found and the vegetation is mainly composed of semi-frutexes and herbages; 3) Most of the essential species distributing here express distinct xeromorphic structures and many of them are typical components of the vegetation of the steppe and semi-dessect, such as Caragana spp., Hololachne soongarica Ehrenb., Artemisia spp., Chrysanthemum neofruticulosum Ledeb., Stipa spp. Achnatherum splendens Ohwi. and so on. Four plant associations are found in this area. Three of them distribute on the Dorthern slope and one on the southern slope of the hill. They are described as follow: Ⅰ. Chenupodium album+Artemisia annua+Elymus dasystachys Association. The distribution of this association is limited to the erosion valleys situating on the piedmont belt of the northern slope at an elevation between 1, 510 and 1, 560 M., where the edaphic condition is marked by high soil moisture content. The climatic features are of low light intencity with short duration of daily sunshine, high relative humidity and low wind velocity. Three hygrophilous and shade-loving species are the main constituents of this association. They are chenopodium album L., Artemisia annua L., and Elymus dasystachys Trin. Other herbaceous plants are Chenopodium glaucum L.. Sonchus aler- aceus L., Xanthium strumarium L., Polygonum amphibium L., P. aviculare L. etc. A few shrubs are present in the association. They are Lycium chinensis Mill., Lonicera heteroloba Batal. and Lonicera ferdinandi Fr. Ⅱ. Artemisia pectinata Association. The Artemisia pectinata Association occurs on the piedmont belt of the northern slope at an elevation varying from 1510 to 1580 M. It occupies the open slope with gradients under 15°. The climatic conditions, in speaking of the northern slope, are rather high in temperature, strong light intencity, low relative humidity and low wind velocity. The projective total cover-degree is about 50% and Artemisia pectinata Pall. appears to be the dominant species in the association. Besides, there are species of thermophilous and heliophilous plants such as Salsola kali L., S. arachnoides‘Moq’. Kung, Cymbaria mongolica Maxim., Artemisia capillaris Thumb., Aster altaicus willd., chrysanthemum neofruticulosum Ledeb., which are frequently scattered among the dominant plants. Plants growing in this association, are all below 10 cm. in height. They give an appearence of open association. Ⅲ. Chrysanthemum neofruticulosum+Artemisia sacrorum var. latiloba—Polytrichum sp. Association. This association, being the largest one in the surveyed area, appears on the northern slope, where it occupies the space ranging from altitude 1,580M. to the top of the hill,2,100M, above the sea level. Soil is of chestnut soil type with a PH value of 8. 0—8. 1.The soil moisture content varies between 6.0 and 7.4%(layer above 60 cm.). In vertical structure, the association consists of two strata. They are described below: Stratum Ⅰ: This stratum includes all shrubs, semi-frutexes and herbages which are taller than 10 cm. in height. Among the plants found in this stratum, chrysanthemum neofruticulosum Ledeb. and Artemisia sacrorum var. latiloba Ledeb. are dominant species and Stipa Bungeana Trin. is the subdominant one. Other species one may frequently meet with are Allium subangulatum Rag., Saussurea nigrescens Maxim., Peganumharmala L., Astragalus dahuricus Dc., Potentilla multifida L., Linum perenne L., Car-agana frutex K. Koch. etc. They spread widely in almost all over the association. Stratum Ⅱ: This stratum is composed of those species less than 10 cm. in height, forming the ground flora of the association. Polytrichum sp. and Lichens are the essential plants in the stratum. One may occasionlly find species of Plantago Lessingii and Gentiana squarrosa Ledeb. growing among those main constituents. The underground stratification of the association has also been studied during the time of surveying. IV. Stipa Bungeana+Aster altaicus+Chrysanthemum neofruticulosum Association. This association distributes on the entire southern slope except the portions tilled for agriculture purposes. The striking local ecological conditions of this association are strong light intensity with long duration of daily sunshine, high temperature, low relative humidity and extremely low in soil moisture content which ranges between 2. 7 and 4. 0% (the layer above 60cm.). On account of the severe destruction of natural vegetation by man and cattle in the past years, the degree of soil erosion is serious throughout the slope where the association locates. The PH value of the soils is 7.4-76. The polydominant plants in this association are Stipa Bungeana Trin., Aster altaicus Willd. and Chrysanthemum neofruticulosum Ledeb. They are quite adaptable to the drought condition of the environment and distribute widely in the association. Besides, other xerophilous or drought resistant plants are frequently met, such as Hololachne soongarica Ehrenb., Linum perenne L., Astranalus dahuricus Dc., Peganum harmala L., Artemisia sacrorum var. latiloba Ledeb., Artemisia capillaris Thumb., Incarvillea Iutea Bur.&Franch., Kochia scoparia Schred. etc. They dispersely grow in the association. In addition to the frequent species mentioned above, Salsola ruthenica Iljin. and S. arachnoides‘Moq’. Kung form seperately micro-associations lying scatterly on the slope. No ground flora stratum may be found and the association shows no above ground stratification. The projective total cover-degree of this association is only about 25-30%. Owing to the difference in the aspects of the northern and sourthern slopes, the climatic and edaphic conditions vary remarkable. Therefore, the vegetation of the surveyed area shows distinctions in distribution, floristic composition, physiognomy, structure, condition in growth and development of plants in the association of different slopes. Taking the floristic composition for example, the following species are entirely absent in the association of the northern slope, yet they are main components on the southern one: Pappophorum brachystachyum Taub. et Spach, Thermopsis lanceolata R. Br., Caragana spinosa Dc., Stellera chamaejasme L., Hololachne soongarica Ehrenb., Nitraria schoberi L., Pennisetum flaccidum Griseb. Differences in elevation also induce striking changes in climatic and edaphic con-ditions especially in aspects of air temperature, relative humidity and soil moisture content. All these gives great influence to the alterations either in quantity or in quality of each species distributing along the northern slope of the area. Following the seasonal change, the physiognomy of the associations expresses sucession of seasonal aspect. Vernal, aestival and autumnal aspects have been observed and recorded.

兰州位于我国的中心,约占北纬36度03分,东经103度57分,拔海1508.53米。皋兰山是兰州四周环山中的最高峰,位居兰州市东南郊。在地形上,皋兰山属于分割黄土高原山岭的一部分,拔海高度约为2100米。由于地理位置及海拔的影响,兰州的气候属大陆性气候类型。年平均温度为6.9℃,年平均雨量为338.6毫米,而61.61%集中在6、7、8、三个月,全年各月平均相对湿度为58%,年蒸发量则达3,571毫米,风力为5.8米/秒。皋兰山山岭的顶部均为厚层的黄土所掩盖,其下则为第三纪红土层。因此,调查区的土壤,全由黄土母质发育而来,含多量钙质,属栗钙土类,PH值为7.6—8.1。调查区的植被,有如下的生志特点:(1)植物种属比较贫乏:全区植物只有41科,93属,124种;(2)群落外貌单纯:调查区内缺乏自然生长的乔木,植被主要由半灌木与草本植物所构成,属干燥草原区的灌木草本群落型;(3)植物具明显旱生形态:群落主要成分,很多是干燥草原区的代表种属,如锦鸡儿属、蒿属、菊属的小黄菊(Chrysanthemum neofruticulosum Ledeb.)、羽茅属、芨芨草等。它们都具有各种适应干旱环境的形态特征。调查区植物...

兰州位于我国的中心,约占北纬36度03分,东经103度57分,拔海1508.53米。皋兰山是兰州四周环山中的最高峰,位居兰州市东南郊。在地形上,皋兰山属于分割黄土高原山岭的一部分,拔海高度约为2100米。由于地理位置及海拔的影响,兰州的气候属大陆性气候类型。年平均温度为6.9℃,年平均雨量为338.6毫米,而61.61%集中在6、7、8、三个月,全年各月平均相对湿度为58%,年蒸发量则达3,571毫米,风力为5.8米/秒。皋兰山山岭的顶部均为厚层的黄土所掩盖,其下则为第三纪红土层。因此,调查区的土壤,全由黄土母质发育而来,含多量钙质,属栗钙土类,PH值为7.6—8.1。调查区的植被,有如下的生志特点:(1)植物种属比较贫乏:全区植物只有41科,93属,124种;(2)群落外貌单纯:调查区内缺乏自然生长的乔木,植被主要由半灌木与草本植物所构成,属干燥草原区的灌木草本群落型;(3)植物具明显旱生形态:群落主要成分,很多是干燥草原区的代表种属,如锦鸡儿属、蒿属、菊属的小黄菊(Chrysanthemum neofruticulosum Ledeb.)、羽茅属、芨芨草等。它们都具有各种适应干旱环境的形态特征。调查区植物群落,可区分为下列的四个群丛: 1.白药+黄花蒿+厚穗滨草群丛(Chenopodium album+Artemisia annus+Elymus dasystachys Association) 本群丛分布于皋兰山山麓的侵蚀沟谷内,约占海拔1510至1560米的地段。所在地气候与土壤特点是光线弱、日照时间短、风力小、大气相对湿度大与土壤潮湿。群丛优势种有白藜、黄花蒿和厚穂滨草三种喜湿耐阴植物。此外,伴生有灰绿藜、苦苣菜、苍耳、两栖蓼、扁蓄等草本植物。灌木则可见枸杞(Lycuim chinensis Mill)、紫金银花(Lonicera heteroloba Batal.)、裴氏金银花(L.ferdinandi.Fr.)三种。 2.篦叶蒿群丛(Artemisia pectinata Association) 这一群丛占据皋兰山北坡山麓海拔1510—1580米,坡度在15°以下的开旷地段。其环境条件,在北坡来说,主要表现于阳光充沛,温度高,大气相对湿度低与土壤干燥。群丛总夏盖度约为50%,而以篦叶蒿最占优势。常见植物有钾猪毛菜、灰蓬(Salsola arachnoides‘moq’Kung)、蒙古芯芭(Cymbaria mongolica Maxim.)、茵陈蒿、阿尔泰紫菀、小黄菊等喜光喜温种类。 3.小黄菊+供蒿-藓群丛(Chrysanthemum neofruticulosum+Artemisia sacrorum var latiloba-Polytrichum sp. Association) 本群丛包括皋兰山北坡自海拔1580米以上一直至山顶(海拔2100米)的全部地段,为调查区内分布面积最广的群丛。其生态环境是阳光弱、日照时间短、蒸发量小、气温低;土镶为栗钙土,PH值在8.0—8.1左右,土壤风干含水量为5.2—5.6%。群丛在垂直结构上,可分为两层:第一层包括高度在10厘米以上的灌木、半灌木与草本植物,而以小黄菊和供蒿最占优势。本氏羽茅则为本属中的亚优势种。常见植物尚有野葱、青木香(Saussurea nigrescens Maxim.)、骆驼蓬、达乌里紫云英,多裂委陵菜、宿根亚麻、木锦鸡儿(Caragana frutex K. Koch.)等。第二层为地被层,主要由藓类和地衣所组成。此外,偶尔出现细叶车前(Plantago Lessingii)与鳞叶龙胆(Gentiana squarrosa Ledeb.)铺地生长。群丛总复盖度约为67%。 4.本氏羽茅+阿尔泰紫菀+小黄菊群丛(Stipa Bungeana+Aster altaicus+Chrysanthemum neofruticulosum Association) 这一群丛占皋兰山南坡除农田以外的全部地区。其气候与土壤条件,可归纳为下:日晒强烈、日照时间长、气温高;人为对自然植被破坏强烈,表土冲刷现象异常严重。土壤水分含量甚低,仅占风干重的1.88—3.41%,pH值为7.4—7.6。本氏羽茅、阿尔泰紫菀与小黄菊为群丛中的主要种类。它们对于干旱的环境均具有强大的适应力。其他常见植物有红砂、宿根亚麻、达乌里紫云英、骆驼蓬、供蒿、茵陈蒿、黄角蒿(Incarvillea lutea Bur.&Franch.)地肤等抗旱或耐旱种类。苏联猪毛菜(Salsola rutheniea Iljin)和灰蓬,常各成单纯小群丛,出现于山坡间。本群丛中缺地被层,无地上成层现象。群丛总复盖度仅为25—30%。由于南北坡取向不同所引起气候与土壤因子的变化,调查区植物群落,在分布、结构、外貌、种类成分及生长发育状况上,也随着发生很大的差异。海拔高度的改变,对气温、相对湿度,土温及土壤水分状况的影晌,也明显地反映在群落中各个种间的数量比例关系上。随着季节的更换,群落中的种类成分,表现出比较显著的季相演替关系。作者等曾作北坡群丛春、夏和秋三季季相的观察与纪录。

This investigation was undertaken to attain by means of pot cultures and chemical analyses a better understanding of the significance of the degree of base saturation in relation to the growth and mineral composition of certain crops. Two relatively pure mineral colloids, bentonite and kaolin, and a lucastrine orchard soil containing illitic type of clay minerals were used for the studies. Bentonite and kaolin were first electrodialyzed and then mixed with different amounts of pure quartz sand to give...

This investigation was undertaken to attain by means of pot cultures and chemical analyses a better understanding of the significance of the degree of base saturation in relation to the growth and mineral composition of certain crops. Two relatively pure mineral colloids, bentonite and kaolin, and a lucastrine orchard soil containing illitic type of clay minerals were used for the studies. Bentonite and kaolin were first electrodialyzed and then mixed with different amounts of pure quartz sand to give different levels of base exchange capacity. Treatments were made to all three cultural media for varying degrees of base saturation with constant ratio between exchangeable bases. Oats and rye were grown in succession in montmorillonitic and kaolinitic media, while peach, soybean, proso, tomato and oats were grown in the illitic soil. Dry weights and contents of certain mineral constituents of oats, rye and tomato were determined. Yield data from the montmorillonitic media showed nearly linear relationship between the degree of base saturation and the growth of the plants. In the kaolinitic media the increase of yield was only noticeable from the first increment of bases, effects above 40% total base saturation being insignificant. The results from illitic soil were intermediate between those mentioned above, i.e., the highest yield of tomato was obtained at the 75% saturation level. The yield data further indicate that the growth of plants was more closely related to the degree of base saturation than to the total supply of exchangeable bases. With the same amounts of bases and at the levels below 60% base saturation, the yields of rye in the kaolinitic colloid were higher than in the montmorillonitic colloid. In the montmorillonitic media, the increase of Ca uptake by the plants from the first increment of Ca was pronounced with only little effects above 30% Ca saturation (or 40% level of total base saturation). The K content of the plants was increased appreciably at only the higher levels of base saturation, while significant increases of the Mg content of the plants occured at lower levels (i.e. below 60% base saturation level). In the kaolinitic media, no appreciable change of Ca and Mg contents of the plants was noticed. This is an interesting contrast to the results obtained with the montmorillonitic media. However, there were definite increases in K content of plants with increasing increments of K at the lower levels of saturation. The higher contents of Ca and Mg in the plants were found in kaolinitic media rather than in the montmorillonitic media provided that the total base saturation level was under 60% of the exchange capacity. On the other hand, the K content of the plants from montmorillonitic media was invariably higher than from kaolinitic media. In the illitic soil, the most marked increase of Ca content in plants occured when the degree of base saturation increased from the 50% to the 75% level. Beyond that point, no appreciable increase was noticed. As the degree of base saturation of illitic soil increased, the K and Mg percentages in plants increased also. Among the conclusions obtained from the experiments, the following are of outstanding significance: 1. Exchangeable cations are not equally available. With the equal supply of total exchangeable cations, their availability varies with the degree of base saturation. Within a certain range, the higher the degree of base saturation, the greater the availability of the exchangeable cation. This affords a theoretical explanation of the advantage of localized application of fertilizers. 2. The availability of exchangeable cations varies with the nature of clay minerals. With the given amount of exchangeable cations and the same degree of base saturation, the individual exchangeable cation held by the clay mineral differs in availability according to the following order: For Ca" and K', kaolinite>montmorillonite>kaolinite. This gives the reason why a montmorillonitic soil should be fertilized with respect to the Ca and K to higher levels than a kaolinitic soil. 3. In order to afford sufficient amount of active cations for the growth of plants, higher degree of ionic saturation is required for Ca" than is for Mg", which in turn should be higher than for K'. The study also discusses, from the theoretical point of view, some of the factors involved in determining the availability of exchangeable bases.

本研究之主要目的在于寻求不同粘粒矿物所吸附的代換性陽离子对植物生長及其矿質营养成分的影响。通过这一試驗,希望了解影响代换性陽离子的若干重要因子,从而提供关于施肥原則及技术的若干理論。试验分温室栽培及植株化学分析兩部份。栽培所用植物包括燕麦、黑麦、小米、大豆、番茄、桃树等数种,培养基根据所合粘番矿物不同,分微晶高陵土系,高陵土系及水化云母系三大类。培养基的鹽基代換率、鹽基飽和度,以及各代换性鹽基間的互相比例,均加以控制。另以砂培处理为对照,試驗的主要結果可以綜結如下: 1.在微晶高陵土系的栽培試驗里,植物的生長概和鹽基飽和度成直线相关,但高陵土系及水化云母系的栽培試驗結果并不完全如此。在这些培养基理,植物的生長,虽然也因鹽基飽和度的增加而改善,但其改善的趋势停止于一定的鹽基飽和度水平上。例如,在本試驗里,对黑麦和燕麦言,当高陵土系培养基的鹽基飽和度达到40%时,或对番茄言, 当水化云母系培养基的鹽基飽和度达到75%时,植物的生長都不再因鹽基飽和度的增加而改善了,这說明就植物的矿質营养言,鹽基飽和度具有特殊重要的意义。一般說来,鹽基飽和度愈大,代换性鹽基的有效度也愈大。 2.作为影响植物矿質营养的土埌肥力因素,鹽...

本研究之主要目的在于寻求不同粘粒矿物所吸附的代換性陽离子对植物生長及其矿質营养成分的影响。通过这一試驗,希望了解影响代换性陽离子的若干重要因子,从而提供关于施肥原則及技术的若干理論。试验分温室栽培及植株化学分析兩部份。栽培所用植物包括燕麦、黑麦、小米、大豆、番茄、桃树等数种,培养基根据所合粘番矿物不同,分微晶高陵土系,高陵土系及水化云母系三大类。培养基的鹽基代換率、鹽基飽和度,以及各代换性鹽基間的互相比例,均加以控制。另以砂培处理为对照,試驗的主要結果可以綜結如下: 1.在微晶高陵土系的栽培試驗里,植物的生長概和鹽基飽和度成直线相关,但高陵土系及水化云母系的栽培試驗結果并不完全如此。在这些培养基理,植物的生長,虽然也因鹽基飽和度的增加而改善,但其改善的趋势停止于一定的鹽基飽和度水平上。例如,在本試驗里,对黑麦和燕麦言,当高陵土系培养基的鹽基飽和度达到40%时,或对番茄言, 当水化云母系培养基的鹽基飽和度达到75%时,植物的生長都不再因鹽基飽和度的增加而改善了,这說明就植物的矿質营养言,鹽基飽和度具有特殊重要的意义。一般說来,鹽基飽和度愈大,代换性鹽基的有效度也愈大。 2.作为影响植物矿質营养的土埌肥力因素,鹽基飽和度的重要性一般超过鹽基代換率。試驗的結果表明:鹽基代換率不等,而鹽基飽和度相等的同一發生学来源的土埌,其植物生長狀况一般相等或相差不远。这說明代換性鹽基的絕对数量不足以指示作物生長的优劣。不仅如此,試驗的結果也啟示出含代換性陽离子絕对数量相等的兩种同源土埌,就对植物的矿質营养言,并不意味着具有相等的供应該有效性陽离子的能力。由于它們間質地上的可能差異,——質地輕者鹽基代换率小,質地粘重者,鹽基代換率大,——因之其鹽基飽和度就不相等。飽和度大者,鹽基的有效度就高。 3.栽培試驗及室內化学分析的結果都表明在总鹽基飽和度为60%以下的土埌中(Ca:Mg:K=15:3:2),高陵土类粘粒矿物上的代换性Ca~(++)及Mg~(++)的有效度均高于微晶高陵土,而K~+則相反。 4.植物矿質成分的化学分析結果表明:各营养离子的鹽基飽和度在一定范圍内的变化,可以显著地影响它进入植物体內的量。例如,当微晶高陵土系培养基的鈣离子飽和度在30%以下的范圍內作增减的变动时,都能明显地反映在其所生長的植物体內的含鈣量上。植物体內的鉀离子,則能反映飽和度自4%至6%的范圍內的变化。鎂的情况大体近似于鉀,只是其变化范圍更小一些。这說明同一种植物为了滿足其自身的营养需要,对于同一种粘粒矿物上所吸附的不同离子,有不同的飽和度的要求。鈣最大,(对黑麦,燕麦而言約30%以上),鎂次之(約9%),鉀最小(約6%)。这些标准也是施肥的最低要求。 5.栽培試驗及化学分析都証明同一种离子吸附在不同的粘粒矿物上,縱然离子飽和度相等,其对植物生長和矿質养分的影响也不相等。研究結果显示出在同一离子飽和度下,不同粘粒矿物上的离子有效度大体依下列次序变化:高陵土>微晶高陵土>水化云母。在农業实踐中,不同类型的土埌所要求的施肥标准不等,在这里也得到了一些理論根据。試驗結果对于实际施肥,应有一定的指导价值。除以上主要結果外,本文还对有关代換性离子有效度的理論問題进行了討論和分析,并提出了作者自己的初步意見。

 
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