茶园土壤铝动态及茶树铝吸收特性

本文报告了在茶园和根际土壤铝动态及茶树铝吸收特性方面的一些研究结果。1.对210个样品测定,茶园土壤交换性铝含量为2.5-988mg/kg,平均238 mg/kg。无定形和层间铝是茶园土壤铝的主要形态;植茶后茶园土壤的水溶性、交换性和有机结合态铝趋于增加。2.茶园土壤交换性铝含量随施氮量的提高而增加;供给茶树NH_4~+-N时,茶树根际土壤(距根表 1mm)的交换性铝显著增加。3.铝在一定范围(≤400 μmol/L)增加茶树侧根数量和长度。4.动力学研究表明茶树根系对铝的吸收表现为可饱和特性,初始时有一快速的吸收过程,并在约6h后转变为缓慢的吸收。

Aluminium in Tea Soils, Rhizosphere Soil and The Characteristics of Al Uptake by Tea Plant

This paper summarized several experiments investigating aluminium in tea soil, rhizosphere and its uptake by tea plants. The main points are as follows. 1. The content of exchangeable Al (1 mol/L KC1) ranged from 2.5 to 988 mg/kg with an average of 238 mg/kg. Amorphous and interlay Al were the main fractions. Tea planting intended to increase of water soluble and exchangeable Al fractions. 2. The content of exchangeable Al increased with the amount of applied nitrogen as urea. Exchangeable Al in rhizosphere (1 mm from the root surface) increased significantly when NH4+-N was supplied. 3. Al absorption by intact tea root was a saturation process with a fast phase at the initial stage and lagged behind after some 6 h. 4. Al below 400mol/L promoted the growth of root, especially increased the number and total length of lateral roots.