摘要
通过浸提试验比较了浓度均为5 mmol L-1的茶多酚(TPs)和低分子有机酸(LMWOAs)对3种酸性土壤矿质元素活化的差异。结果表明:对于Si、Al、Fe,其活化量在漂洗水稻土和黄壤上为LMWOAs>TPs,在酸性紫色土上则为TPs>苹果酸(Si的活化量为TPs>LMWOAs),表明TPs在初育土脱硅过程中发挥着重要作用,预示植茶有利于初育土向地带性土壤演化;对于盐基离子,3种土壤Ca的活化量均为苹果酸>TPs,Mg、K的活化量均为LMWOAs>TPs,Na的活化量均为茶叶提取物>柠檬酸>苹果酸(在漂洗水稻土上为TPs>LMWOAs);TPs对Ca、K、Na的活化量均以漂洗水稻土最大,表明植茶可显著促进漂洗水稻土盐基离子的活化与迁移,在提高其有效性的同时可能加速土壤酸化。
Experiments were carried out using extractants prepared out of deionized water with tea polyphenols （TPs, including tea extracts, catechin and epigallocatechin gallate） and low-molecular-weight organic acids （LMWOAs, including oxalic acid, citrate acid and malic acid） 5 mmol L-1 each in concentration, separately, to extract 3 types of acid soil （Albic Fe-accumuli-Stagnic Anthrosols, Typic Haplic-Perudic Argosols and Dystric Purpli-Udic Cambosols） for comparison between the two groups of extractants in effect of mobilizing soil mineral elements in the soils. Results show that the effects of TPs mobilizing soil Si, Al and Fe were higher in Dystric Purpli-Udic Cambosols than in Albic Fe-accumuli-Stagnic Anthrosols and Typic Haplic-Perudic Argosols, the three organic LMWOAs differed in the effect, displaying an order of oxalic acid 〉 citric acid 〉 malic acid, and their effects were more significant than TPs’ in the Albic Fe-accumuli-Stagnic Anthrosols and in the Typic Haplic-Perudic Argosols, but not in the Dystric Purpli-Udic Cambosols, where TPs were higher than malic acid in the effect （especially in effect of mobilizing Si, TPs were even higher than all the LMWOAs）, which demonstrates that TPs really play an important role in desilicating primitive soil through complexing action and proton effect, and hence predicts that tea cultivation may be conducive to the evolution of the soils into zonal soils; The effects of TPs and LMWOAs were more significant on Al than on that Si and Fe in all the three soils, and moreover, mobilization of Si, Al and Fe occurred simultaneously, which indicates that TPs and LMWOAs may get complexed more efficiently with Al, thus lowering its toxicity, but on the other hand, increasing its mobility and facilitating its entrance into water body and the environment. In terms of effect mobilizing soil base ions, in case of Ca, malic acid was higher than TPs; in the case of Mg and K, LMWOAs were higher than TPs; and in the case of Na, tea extracts ranked first, and were followed by citric acid and then malic acid, and in Albic Fe-accumuli-Stagnic Anthrosols, TPs were higher than LMWOAs. The effects of LMWOAs and TPs mobilizing soil base cations, especially Ca, K and Na, were the highest in Albic Fe-accumuli-Stagnic Anthrosols, and the three base cations though followed an order of Ca 〉 Mg 〉 K in amount mobilized, they were being mobilized simultaneously. So the use of Albic Fe-accumuli-Stagnic Anthrosols for tea cultivation would promote mobilization and migration of Ca, K and Na, which would improve bioavailability of these base cations on the one hand and accelerate soil acidification on the other. It is, therefore, essential to further intensify systematic study of the effects of TPs on mobilization and migration Si, Al and Fe in primitive soils and the effects of conversion of Albic Fe-accumuli-Stagnic Anthrosols into tea gardens on mobilization and migration of base cations in the soil.
出处
《土壤学报》
CAS
CSCD
北大核心
2014年第6期1378-1387,共10页
Acta Pedologica Sinica
基金
国家自然科学基金面上项目(41371230)资助
关键词
茶多酚
低分子有机酸
矿质元素
活化
Tea polyphenols
Low-molecular-weight organic acids
Mineral elements
Mobilization
