地理学报 ›› 1997, Vol. 52 ›› Issue (5): 461-469.doi: 10.11821/xb199705010

• 论文 • 上一篇    下一篇

人工控制土壤水分剖面调控根系分布的研究

冯广龙, 刘昌明   

  1. 中国科学院国家计划委员会地理研究所, 北京 100101
  • 出版日期:1997-09-15 发布日期:1997-09-15
  • 基金资助:
    国家重大自然科学基金

STUDIES ON THE CONTROL OF SOIL WATER PROFILE AND ROOT DISTRIBUTION

Feng Guanglong, Liu Changming   

  1. Institute of Geography, Chinese Academy of Sciences, Beijing 100101
  • Online:1997-09-15 Published:1997-09-15

摘要: 1995年~1996年在中科院栾城农业生态系统联合站进行了控制土壤水分剖面分布的灌溉试验,详尽考察分析了根系生长分布、水分利用方式、冠部营养生殖生长,耗水特性及水分利用率的灌溉效应。结果表明:根系分布随土壤含水量降低相应减少,呈水大根大特征,上部干旱促使根系向深层发育,利用下层水量较多。小定额频灌在0cm~30cm表层根系分布量占总根量61%,根系吸水效率较高,利用该层的水量占1m土体总耗水量74%,棵间蒸发占总蒸散量28%,只比常规灌溉多4%,产量与水分利用率则分别提高了17%和11%。常规灌溉与只灌冬水旱作处理,在50cm以下土层根系占各自总根量分别为37%、30%,下层根系吸水效率较大,分别利用的水量占各自总耗水量比例为22%和29%。扬花期茎叶重、LAI及根量达一生最大值,根系日增长率最大,为0.2cm/cm·d~0.25cm/cm·d。各灌溉处理在扬花、灌浆期蒸散和蒸腾强度最大,蒸散强度各为5.5mm/d、4.6mm/d,蒸腾强度分别为4.6mm/d、3.3mm/d。棵间蒸发强度在拔节期最大,各处理平均约为1.3mm/d,占总蒸散量38%。

关键词: 等量不等次灌溉, 灌溉湿润深度, 根系分布, 耗水特性, 冬小麦

Abstract: There are feedback interrelationships between shoot and root, namely shoot growth and development could be controlled by root growth and distribution which can be also adjusted by soil moisture distribution in soil profile. In order to determine an optimum irrigation method for controlling water distribution with depths which could adjust effectively root growth and distribution in soil profile, the field experiment with four treatments of irrigation application depth and frequency (once irrigation, the same amount of water was irrigated by 1,2 and 3 times, respectively) were conducted from 1995-1996 at Luancheng Experimental Station of Agricultural Ecosystems, Chinese Academy of Sciences, which located in the North China Plain. Under different irrigation conditions, shoot growth, grain yield, root growth and distribution, soil water extraction patterns, consumptive water use, and water use efficiency (WUE) were investigated in detail. The more soil water content, the higher the rooting density, the density was reduced by decreased soil moisture content. Root length density was much more in the deeper layer due to soil water stress on the top of layer, meanwhile, more amount of soil water was depleted. Soil water extraction patterns were correlated to rooting distributions. Under frequent, light irrigation treatment (I3), soil moisture content and extraction efficiency were higher at 0 cm-30 cm layer in which 61% total root length density was observed, 74% total amount of water was consumed from the layer, the proportion of soil evaporation to evapotranspiration was 28% which was only 4% greater than the conventional irrigation (I1). Grain yield and WUE were improved separately by 17% and 11% in comparison with I1 treatment. Under I1 and rainfed treatment (CK), 37% and 30% total amount of root distributed in 50 cm-100 cm depth of soil from which 22% and 29% total amount of water were extracted, respectively. The crop achieved its maximum LAI and dry matter of stem and leaf at flowering stage, the rate of root elongation is the highest over growing season in the period (0.2 cm/cm 3穌-0.25 cm/cm 3穌). Average the maximum evapotranspiration rate (5.5 mm/d, 4.6 mm/d) and transpiration rate (4.6 mm/d, 3.3 mm/d) of all irrigation treatments occurred in flowering and filling stages. Otherwise, the average rate of soil evaporation is 1.3 mm/d during jointing stage which is the highest rate from jointing to maturing.

Key words: irrigation frequency, irrigation application depth, root distribution, water extraction patterns, water consumptive characteristics, winter wheat

中图分类号: 

  • S152.7