A Device for Simulating Soil Nutrient Extraction and Plant Uptake  

作　　者：YANG Xu-Jian LAI Yong-Lin MO Jin-Yu SHEN Hong 

机构地区：[1]Laboratory of Root Layer Control,College of Natural Resources and Environment,South China Agricultural University,Guangzhou 510642(China)

出　　处：《Pedosphere》2012年第6期755-763,共9页土壤圈（英文版）

基　　金：Supported by the National Natural Science Foundation of China (Nos. 31071847 and 31172026);the National Basic Research Program (973 Program) of China (No. 2007CB109303);the Ph.D. Programs Foundation of Ministry of Education of China (No. 20104404110016);the Foundation for High-Level Talents in Higher Education of Guangdong, China;the Preferred Foundation for Returned Scholars, Ministry of Personnel of China (No. 2010412)

摘　　要：In situ evaluating the availability of soil nutrients has been a challenge. In this study, a new type of Device for Simulating Soil Nutrient Extraction and Plant Uptake （DSSNEPU） and its operating procedures were introduced. The device consists of a sampling tube, a fluid supply system, a low pressure system, a tube sheath and an elution cylinder. The sampling tube was firstly soaked in the solution of 0.5 mol L-1 NaHCO3 and then buried into soils. The fluid supply system was connected to the sampling tube and the deionized water was supplied. During the period, low pressure system started a vacuum for 3 min every 10 rain interval. After extraction, the sampling tube was removed and the nutrients on the sampling tube were eluted with 0.5 tool L-1 HCl. The elution solution was used for nutrient measurement. The amounts of P and K extracted by DSSNEPU reached the maximal values after 4 h. No significant increases of P and K were observed for longer extraction duration. The optimal temperature for extracting P and K was 30 ℃ in this experiment. Extracted P and K were increased by 83.3% and 84.6% with the employment of low pressure system in comparison to those without employing low pressure system. Correlation analysis indicated that 1~ and K extracted by DSSNEPU were highly correlated with those by conventional chemical extraction and by plant uptake. The above results suggest that this device is applicable to assess the availability of nutrients in soils.In situ evaluating the availability of soil nutrients has been a challenge. In this study, a new type of Device for Simulating Soil Nutrient Extraction and Plant Uptake (DSSNEPU) and its operating procedures were introduced. The device consists of a sampling tube, a fluid supply system, a low pressure system, a tube sheath and an elution cylinder. The sampling tube was firstly soaked in the solution of 0.5 mol L 1 NaHCO 3 and then buried into soils. The fluid supply system was connected to the sampling tube and the deionized water was supplied. During the period, low pressure system started a vacuum for 3 min every 10 min interval. After extraction, the sampling tube was removed and the nutrients on the sampling tube were eluted with 0.5 mol L 1 HCl. The elution solution was used for nutrient measurement. The amounts of P and K extracted by DSSNEPU reached the maximal values after 4 h. No significant increases of P and K were observed for longer extraction duration. The optimal temperature for extracting P and K was 30 C in this experiment. Extracted P and K were increased by 83.3% and 84.6% with the employment of low pressure system in comparison to those without employing low pressure system. Correlation analysis indicated that P and K extracted by DSSNEPU were highly correlated with those by conventional chemical extraction and by plant uptake. The above results suggest that this device is applicable to assess the availability of nutrients in soils.

关 键 词：available nutrients conventional chemical extraction ion exchange membrane low pressure system soil nutrient evaluation 

分 类 号：TQ443[化学工程—化学肥料工业] S158.3[农业科学—土壤学]