水稻对土壤营养元素吸收系数及吸收限的研究

Soil Nutrient Elements Absorptivity and Absorption Edge Of Rice

通过研究广东省江门市三个不同优质稻产地土壤中相同元素对水稻品质造成不同影响的特点,如都斛土壤中的N与水稻胶稠度呈正相关关系,而在牛江则呈较强负相关关系;都斛土壤中的Mo与水稻的不完善粒呈较强负相关关系,而在牛江则呈正相关关系。根据吸收系数与土壤营养元素关系,得出作物对营养元素的吸收限。当土壤能给作物提供足够的营养元素时,作物对土壤营养元素的吸收存在一个极限,土壤元素含量接近这个极限时,作物对元素的吸收达到饱和,对元素的吸收系数则低;当土壤营养元素供给能力不足时,作物对营养元素吸收能力较强,对元素吸收系数较高。通过对比各元素及指标与稻谷感官品质相关关系并评分,得出土壤营养元素含量越偏离水稻对营养元素的吸收限,则对水稻品质的影响越大的结论,由此解释了不同省份农业地质调查中农作物元素与土壤元素相关关系混乱甚至矛盾的问题。

The same elements in the soils of three different high-quality rice producing areas in Jiangmen,Guangdong Province,were studied to find out their different effects on rice quality.For example,N in soil has a positive correlation with Gel Consistency in rice at Duhu,whereas at Niujiang the correlation was more negative;Mo in soil has a strong negative correlation with imperfect grains of rice,while at Niujiang there is a positive correlation.According to the relationship between absorption coefficient and soil nutrient elements,there exists a crop absorption edge to nutrients elements—when soil can provide adequate nutrients to crops,the crop uptake of soil nutrients has a limit.When the element contents in the soils approach to the limit,the absorption of elements in crops will reach saturation and the absorption coefficient of the element is lower;when the soil nutrient supply is insufficient,the crop nutrient absorption ability is strong,and the absorption coefficient of the element is high.In terms of the relationship between various elements and rice sensory quality,it is concluded that the more the soil nutrient element contents deviate from the absorption edge,the greater the impact on rice quality.Thus,it explains the confusing and even contradictory issues of the relationship between crop elements and soil elements in different provinces＇ geological survey and provides the scientific and rational basis for rice fertilization.