广西红壤区桉树林地土壤酸化特征及控酸技术初探  

Study on soil acidification characteristics and acid control technology of Eucalyptus forest in Guangxi red soil region

作　　者：柯琴 韦向向 赵隽宇 覃祚玉[1] 宋贤冲[1] 曹继钊[1] 吴立潮[3,4] 唐健[1] KE Qin;WEI Xiang-xiang;ZHAO Jun-yu;QIN Zuo-yu;SONG Xian-chong;CAO Ji-zhao;WU Li-chao;TANG Jian(Guangxi Forestry Research Institute,Guangxi Research and Development Center for New Fertilizer,Nanning Guangxi 530002;College of Forestry,Guangxi University,Nanning Guangxi 530004;Key Laboratory of Soil and Water Conservation and Desertification Combating in Central South University of Forestry and Technology,Changsha Hunan 410004;Key Laboratory of Cultivation and Protection for Non-wood Forest Trees of Ministry of Education,Changsha Hunan 410004)

机构地区：[1]广西壮族自治区林业科学研究院/广西林用新型肥料研发中心,广西南宁530002 [2]广西大学林学院,广西南宁530004 [3]中南林业科技大学水土保持与荒漠化防治湖南省高等学校重点实验室,湖南长沙410004 [4]中南林业科技大学经济林培育与保护省部共建教育部重点实验室,湖南长沙410004

出　　处：《中国土壤与肥料》2024年第11期49-56,共8页Soil and Fertilizer Sciences in China

基　　金：广西林科院基本科研业务费项目(林科202308号);中央引导地方科技发展资金项目(桂科ZY21195026);广西自然科学基金项目(2022GXNSFBA035630)。

摘　　要：高强度连续种植桉树人工林的土壤酸度呈明显下降趋势,土壤酸化已成为制约桉树林地土壤质量的主要障碍因子之一。然而,单从活性酸角度无法全面评价桉树人工林土壤酸化状况,同时缺乏桉树人工林土壤控酸技术研究。采集广西桂北红壤区桉树人工林土壤样品,测定酸碱度、交换性酸含量、酸缓冲容量等指标,分析土壤游离酸和潜在酸分布特征,并以3种有机控酸剂(腐植酸盐类、黄腐酸盐类和氨基寡糖类)和2种无机缓冲剂(磷酸二氢钾和磷酸氢二钾)为备选材料,两两搭配构建有机无机控酸体系,筛选出缓冲能力较好的3种有机无机控酸体系,开展控酸效果对比试验,探讨上述3种控酸体系对土壤酸度的动态影响。结果表明,广西红壤区桉树人工林土壤呈强酸性,p H值范围为4.50~4.85,交换性Al^(3+)含量为2.60~4.30 cmol/kg,平均土壤酸缓冲容量为38.90 mmol/kg。缓冲性能较好的3种有机无机控酸体系分别为5∶1的氨基寡糖类+磷酸氢二钾、10∶1的黄腐酸盐类+磷酸二氢钾和10∶1的腐植酸盐类+磷酸二氢钾,上述3种降酸体系施用30 d后,与空白对照相比,土壤p H值分别提升1.17、0.98和0.73,增幅分别达25.36%、21.24%和15.82%;交换性Al^(3+)含量分别减少了2.7、0.8、2.2 cmol/kg,下降幅度达74.07%、24.07%和62.04%。广西红壤区桉树人工林土壤呈强酸性,土壤对外源酸稍敏感,稍易受酸害。交换性Al^(3+)是主体致酸因子,其含量高于作物铝胁迫临界点。综合考虑3种控酸体系对土壤酸度的影响,氨基寡糖类与磷酸氢二钾配施对广西红壤区桉树人工林土壤控酸效果最佳,后续田间试验效果有待进一步验证。In recent years,the pH value of Eucalyptus plantation soil in Guangxi decreased obviously,and soil acidification has gradually become the main obstacle factor restricting the soil quality of Eucalyptus plantation.However,soil acidification status of Eucalyptus plantation soil cannot be evaluated from the perspective of active acid alone,and soil acid control technology of Eucalyptus plantation is lacking.Based on the soil acidification characteristics of Eucalyptus plantation in Guangxi red soil region,the acid control system was constructed and the acid control effect of each acid control system was compared to provide a scientific basis for alleviating soil acidification of Eucalyptus plantation.Soil samples of Eucalyptus plantation in Guangxi red soil region were collected to determine pH value,exchangeable acid content and acid buffer capacity,and to analyze the distribution characteristics of free acid and potential acid in soil.With three organic acid control agents(humates,xanthulates and amino oligosaccharides)and two inorganic buffers(potassium dihydrogen phosphate and dipotassium hydrogen phosphate)as alternative materials,the organic-inorganic acid control systems were constructed by pairwise collocation.Three kinds of organic-inorganic acid control systems with the best buffer capacity were selected,and the dynamic effects of three kinds of acid control systems on soil acidity were measured by comparison of acid control effects.The results showed that the pH value of strongly acidic soil of Eucalyptus plantation in Guangxi red soil region ranged from 4.50 to 4.85,the content of exchangeable Al^(3+)was 2.60-4.30 cmol/kg,and the average buffer capacity of soil acid was 38.90 mmol/kg.The three organic-inorganic acid control systems with the best buffer performance were 5∶1 amino oligosaccharides+dipotassium hydrogen phosphate,10∶1 xanthohuate+potassium dihydrogen phosphate and 10∶1 humate+potassium dihydrogen phosphate.After 30 days of application of the above three acid reduction systems,compared

关 键 词：红壤 桉树人工林 土壤酸化 有机物料 交换性酸 

分 类 号：S714.6[农业科学—林学]