Water absorption by plants: available versus extractable soil water and crop production

Ciência Rural

Carlesso, Reimar¹ 

[1] Universidade Federal de Santa Maria, Santa Maria

关键词: available water;    water extraction;    root growth;   

DOI  :  10.1590/S0103-84781995000100035

学科分类：农业科学（综合）

来源: Universidade Federal de Santa Maria * Centro de Ciencias Rurais

【 摘 要 】

An important issue to understanding the effect of water shortage on crop yield is how crops balance the supply of water from the soil to match the demand for water from the atmosphere. Supply is determined by the crop ability to utilise the stored soil water and, demand, on the other hand, is determined by a combination of metereological factors interacting with the crop canopy. Different criteria have been used to determine the timing and duration of water deficits despite the abundant literature available. Much attention has been given to the quantification of crop water consumption in different stages of development. However, considerations about the total amount of plant water available (extractable) in the soil profile to affect plant growth and development have recieved little attention. A discussion of water extraction must first consider the problem of accurately defining the limits to soil water availability. This review presents a critical analysis of the limitations usually encountered in using the limits concept of soil water availability. The relationship between water available and extractable is analysed based on results of transpiration rates and fraction of available water, depth of water extraction and, extraction per unit soil depth.

【 授权许可】

CC BY-NC