摘要
选取菜子湖区不同退耕年限（3、5、7、9、11和21 a）湿地、以仍耕油菜地和原始湿地土壤为研究对照，分析了土壤全铝和活性铝形态组分特征，探讨退耕还湖后湿地土壤铝元素组分特征变化及其生态效应。结果表明，研究区土壤全铝含量和活性铝含量分别在16．78-57．05 g瓜g和1 699．94～3 823．49 meC/kg之间，其中活性铝总量占全铝含量的6．70％～11．84％。退耕还湖3-11a期间，土壤全铝、活性铝总量及5种形态活性铝总体均随退耕年限延长而增加；退耕11～21 a期间均下降。不同形态活性铝中，可溶性铝Als含量最低，而酸溶无机铝Al（OH）2和腐殖酸铝Al-HA含量较高，分别占活性铝总量的42％～53％和39%-50％，左右着活性铝总量的变化。分析讨论表明退耕后湿地植被和水文条件的改变导致土壤粘粒，有效磷和有机质的变化，进而影响退耕后土壤活性铝组分特征。其中0-5 cm土壤毒性较强的交换性铝Al3＋和羟基铝Al（0H）^2＋、Al（OH）2^＋含量均在退耕3-9 a期间逐渐增加，占活性铝总量的比例也有所增加，该退耕期湿地土壤存在一定的铝毒生态风险。
Soils were sampled in rape field, native wetland, and wetland retumed from farmland to lake （RFL） withindifferent periods （3, 5, 7, 9, 11 and 21a） and analyzed the distribution of active aluminum forms in the Caizi Lake, AnhuiProvince. The results showed that the contents of soil total aluminum （A1T） and active aluminum （AIA） were 16.78-57.05g/kg and 1 699.94-3 823.49 mg/kg respectively, moreover A1n accounted for 6.70%-11.84% of soil A1T in studied fields.The contents of A1T, A1A and other five active aluminum forms increased with the increase of RFL age within therestoration period of 3-1 la, and declined gradually after 1 la of RFL. Among the active aluminum forms, solutionaluminum （Als） was the lowest. Acid-soluble inorganic aluminum [AI（OH）2 ] and humic-acid aluminum [A1-HA] werehigher, which accounted for 42%-53% and 39%-50% of soil A1A respectively, which dominated the change of A1A. Theresults indicated that the variation of soil clay, organic matter and available phosphorus was due to the change of wetlandvegetation and hydrological conditions, which resulted in the characteristics of soil active aluminum components after RFL.The results also indicated that the most toxic forms of aluminum, exchange aluminum （A13＋） and unimer hydroxylaluminum [AI（OH）2＋AI（OH）2＋ ] increased gradually within the restoration period of 3-9 a. Wetland soils sustainedecological risk of aluminum toxicity in the period of 3-9 a after RFL.
出处
《长江流域资源与环境》
CAS
CSSCI
CSCD
北大核心
2016年第2期307-315,共9页
Resources and Environment in the Yangtze Basin
基金
国家自然科学基金项目(41001369
41301249)
安徽省自然科学基金项目(1308085MD22)~~
关键词
退耕还湖
湿地土壤
活性铝形态
铝毒
returning farmland to lake
wetland soil
forms of active aluminum
aluminum toxicity
