摘要
通过田间小区试验,分析了不同用量的生物炭处理下(0,10,20,30,40 t/hm~2)0—17,17—29 cm土层土壤的理化性质、重金属钝化及酶活性的影响。采用IFI(土壤肥力综合质量指数)评价了土壤肥力状况。结果表明:施用生物炭可以改善红壤的理化性状,降低土壤容重,提高土壤的孔隙度、饱和含水量、pH、CEC、有机质、有效磷、铵态氮和全氮及DOC含量;同时提高土壤脲酶、过氧化氢酶和蔗糖酶活性。土壤有效态Cd和Pb含量均随生物炭施用量的增加而减少;而有效态As含量则随生物炭施用量的增加呈先增后减的趋势,三者均在生物炭施用量为40 t/hm~2时为最小值。利用IFI对土壤肥力综合质量进行评价可知,在不同生物炭用量条件下土壤肥力综合质量指数依次为A30>A40>A20>A10>CK,相应的土壤肥力综合质量指数分别为0.64,0.62,0.57,0.47,0.44。评价结果表明在生物炭施用量为30 t/hm~2时,红壤的肥力改良效果最佳。因此,采用适量的生物炭可修复重金属对红壤性水稻土的污染,并改善土壤肥力状况。
Field plot experiments were conducted to study the effects of biochar on soil physi-chemical properties, heavy metal passivation and enzyme activities in the red paddy soil polluted by heavy metals. Biochar was added in different amounts of 0, 10, 20, 30 and 40 t/hm~2, respectively. The soil samples were collected from 0-17 and 17-29 cm soil layers. The soil integrated fertility index(IFI) was used to assess the soil fertility. The results showed that biochar could increase soil fertility by reducing soil bulk density and improving soil porosity, saturated water content, pH, cation exchange capacity(CEC) and the content of soil organic matter(SOM), the available phosphorus, ammonium nitrogen, total nitrogen and dissolved organic carbon(DOC). Meanwhile, biochar could improve activity of soil urease, catalase and urease. The content of available Cd and Pb in soil decreased with the increasing of biochar application amount, whereas the available As content increased first and then decreased with the increasing of biochar amount. The content of available Cd, As and Pb were all minimum when the biochar application was 40 t/hm~2. According to the evaluation of soil quality by IFI, the order of soil fertility composite quality was followed A30>A40>A20>A10>CK, the corresponding soil fertility composite quality indexes were 0.64, 0.62, 0.57, 0.47, 0.44, respectively. The evaluation results suggested that the optimal amount of biochar was 30 t/hm~2 for improving the red paddy soil fertility. In conclusion, appropriate amount of biochar application could remedied the red peddy soil polluted by heavy metal and enhance soil fertility.
引文
[1] Wu C F,Zhang L M.Heavy metal concentrations and their possible sources in paddy soils of a modern agricultural zone,southeastern China [J].Environmental Earth Sciences,2010,60(1):45-56.
[2] Lu S,Wang Y,Teng Y,et al.Heavy metal pollution and ecological risk assessment of the paddy soils near a zinc-lead mining area in Hunan [J].Environmental Monitoring and Assessment,2015,187(10):e627.
[3] Gregory S J,Anderson C W N,Arbestain M C,et al.Response of plant and soil microbes to biochar amendment of an arsenic-contaminated soil [J].Agriculture Ecosystems and Environment,2014,191:133-141.
[4] Liu Z,Demisie W,Zhang M.Simulated degradation of biochar and its potential environmental implications [J].Environmental Pollution,2013,179:146-152.
[5] 郭利敏,艾绍英,唐明灯,等.不同改良剂对镉污染土壤中小白菜吸收镉的影响[J].中国生态农业学报,2010,18(3):654-658.
[6] 赵青青,王海波,夏运生,等.生物质炭对根际土壤中镉形态转化及水稻镉累积的影响[J].生态环境学报,2016,25(9):1534-1539.
[7] Fang S,Tsang D C,Zhou F,et al.Stabilization of cationic and anionic metal species in contaminated soils using sludge-derived biochar [J].Chemosphere,2016,149:263-271.
[8] Karer J,Zehetner F,Dunst G,et al.Immobilization of metals in a contaminated soil with biochar compost mixtures and inorganic additives:2-year greenhouse and field experiments [J].Environmental Science and Pollution Research,2018,25(3):2506-2516.
[9] 南京农学院.土壤农化分析[M].北京:农业出版社,1980.
[10] 关松荫.土壤酶及其研究法[M].北京:农业出版社,1986.
[11] 徐建明.土壤质量指标与评价[M].北京:科学出版社,2010.
[12] Nannipieri P,Giagnoni L,Renella G,et al.Soil enzymology:Classical and molecular approaches [J].Biology & Fertility of Soils,2012,48(7):743-762.
[13] Novak J M,Lima I,Xing B S,et al.Characterization of designer biochar produced at different temperatures and their effects on a loamy sand [J].Annals of Environmental Science,2009,3:195-206.
[14] Leifeld J,Fenner S,Müller M.Mobility of black carbon in drained peatland soils[J].Bio-geosciences,2007,4(2):425-432.
[15] 张伟明.生物炭的理化性质及其在作物生产上的应用[D].沈阳:沈阳农业大学,2012.
[16] Farrell M,Kuhn T K,Macdonald L M,et al.Microbial utilization of biochar-derived carbon [J].Science of the Total Environment,2013,465(6):288-297.
[17] 肖婧,徐虎,蔡岸冬,等.生物质炭特性及施用管理措施对作物产量影响的整合分析[J].中国农业科学,2017,50(10):1830-1840.
[18] 朱美玲,贡璐,张龙龙.塔里木河上游典型绿洲土壤酶活性与环境因子相关分析[J].环境科学,2015,36(7):2678-2685.
[19] Czimczik C I,Masiello C A.Controls on black carbon storage in soils [J].Global Biogeochemical Cycles,2007,21(3):1-8.
[20] 贺玉晓,赵同谦,刘刚才,等.采煤沉陷区土壤重金属含量对土壤酶活性的影响[J].水土保持学报,2012,26(1):214-218.
[21] 吴萍萍,李录久,李敏.生物炭负载铁前后对复合污染土壤中Cd、Cu、As淋失和形态转化的影响研究[J].环境科学学报,2017,37(10):3959-3967.
[22] Luke B,Eduardo M J,Jose L,et al.A review of biochars’ potential role in the remediation,revegetation and restoration of contaminated soils [J].Environmental Pollution,2011,159(12):3269-3282.
[23] 苏耀明,陈志良,雷国建,等.多金属矿区土壤重金属垂向污染特征及风险评估[J].生态环境学报,2016,25(1):130-134.
[24] Topoliantz S,Ponge J F,Ball of S.Manioc peel and charcoal:A potential organic amendment for sustainable soil fertility in the tropics [J].Biology & Fertility of Soils,2005,41(1):15-21.
[25] Yang Y,Yan J L,Ding C.Effects of biochar amendment on the dynamics of enzyme activities from a paddy soil polluted by heavy metals [J].Advanced Materials Research,2012,610/613:2129-2133.