扬州市耕地土壤pH值30年演变及其驱动因子
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摘要
【目的】土壤p H值是衡量耕地质量的重要指标,开展江苏省扬州市30年来种植制度、耕作制度、施肥、降雨等对耕地土壤酸化影响的研究,为预测和控制土壤酸化提供科学依据。【方法】调查了1984年、1994年、2005年、2014年四个时期耕地土壤p H、成土母质、土壤类型、土壤有机质含量,以及各时期的耕作制度、种植制度、降雨量和施用化肥品种和数量。数据来源于1984年第二次土壤普查的农化样点(4107个)、1994年的土壤普查点(2862个)、2005年土壤养分调查点(4018个)、2014年土壤养分调查点(6009个),共16996个。参照《中国土壤》对我国土壤酸碱度分级指标将扬州市耕地土壤p H分为5级,分别为Ⅰ级(>7.5)、Ⅱ级(6.5~7.5)、Ⅲ级(5.5~6.5)、Ⅳ级(4.5~5.5)、Ⅴ级(<4.5)。应用地统计学中克里格法(Kriging)和相关的统计学方法,用Arc GIS10.1、SPSS19等软件进行了数据统计分析。【结果】扬州市1984年、1994年、2005年、2014年土壤p H平均分别为7.51(4107个)、7.07(2862个)、6.83(4018个)、6.74(6009个);1984~2014年四个时期土壤p H空间分布格局基本不变,即里下河地区>沿江圩区>通南高沙土区>丘陵地区。1984、1994年和2005年,土壤p H以Ⅰ级、Ⅱ级为主,1984年占总面积的90%以上,1994年和2005年占总面积的75%以上;2014年土壤p H空间分布以Ⅱ级、Ⅲ级水平为主,占总面积的65.7%。30年间,土壤p H值下降0~1个单位的面积占总面积的47.2%,下降大于1个单位的面积占总面积的39.3%。前20年土壤p H值下降严重,下降了0~2个单位的面积占80%以上。30年间不同成土母质、土壤类型的整体土壤p H值呈下降趋势,分别下降0.9、0.8个单位;土壤有机质含量的变化与土壤p H变化呈负相关关系,30年间土壤有机质含量平均上升了6.01 g/kg,是土壤p H整体呈下降趋势的原因之一;30年间扬州市降水p H值整体呈下降趋势,其中丘陵、沿江地区下降最快,与丘陵、沿江地区土壤p H下降较快是一致的;30年间化肥投入量与土壤p H变化呈高度的负相关,2005年化肥投入量约505300吨,比1984年化肥投入量增加了2.42倍;2005~2014年化肥投入量呈稳定趋势,与30年土壤p H变化趋势是一致的;种植大棚蔬菜的田块土壤p H平均值比周边种植稻麦田块下降1.5~2个单位,表明土地利用类型改变也会影响土壤p H值。【结论】扬州市耕地土壤p H值30年间持续下降,前20年下降幅度较大,后10年渐趋稳定。影响土壤p H值空间分布因子主要有成土母质、土壤类型、土壤有机质含量;影响土壤p H时间分布因子主要有酸雨、施肥及土地利用类型,其中酸雨、施肥是导致土壤酸化的主要驱动因子。
【Objectives】Soil p H is an important index to measure quality of cultivated lands. The influence of cropping system, cultivation system, rainfall and fertilization practices on soil acidification over the last 30 years was investigated.【Methods】This study investigated soil p H, soil parent material, soil type, soil organic matter content in 1984, 1994, 2005 and 2014, and the cultivation system, cropping system, rainfall, types of fertilizer application and their inputs in these years. The data came from 16996 sampling points in Yangzhou City,including 4107 agricultural chemical soil samples of the second general soil survey in 1984, 2862 general soil survey points in 1994, 4018 soil nutrients survey points in 2005, and 6009 soil nutrients survey points in 2014.Referencing to Chinese Soils, we classified the soil p H into five grades:Ⅰ(> 7.5), Ⅱ(6.5–7.5), Ⅲ(5.5–6.5), Ⅳ(4.5–5.5), and Ⅴ(< 4.5). The method of Kriging and relevant statistical methods in geostatistics were used in this study, and Arc GIS 10.1 and SPSS19 were used as tools for analyzing data.【Results】The results showed that the average soil p H was 7.51, 7.07, 6.83 and 6.74 respectively in 1984, 1994, 2005 and 2014. The spatial distribution of p H in the four periods was relatively constant, i.e. Lixiahe area > Yangtze River diked area > Sandy soil area in Tongnan > Hilly region. In 1984, 1994 and 2005,the soil p H mainly belonged to Grade I and II, which accounted for more than 90% of total area in 1984 and decreased to 75% in 1994 and 2005; in 2004, the soil p H mainly belonged to Grade Ⅱ and Ⅲ, which accounted for 65.7% of total area. In 30 years, soil p H was significantly decreased, 47.2% areas decreased by 0–1 unit and 39.3% areas decreased by more than 1 unit. In the first 20 years, soil p H was obviously declined and over 80% area soil p H declined by 0–2 units. The overall soil p H of different soil parent materials and soil varieties decreased by 0.9 unit and 0.8 unit, respectively.There was a negative correlation between changes of soil organic and p H. The average content of soil organic matter was increased by 6.01g/kg, it was one of the reasons for the decrease of soil p H as a whole. The p H value of the rainfall in this city decreased, especially rapid for the hills and areas alongside the river. This was consistent with the view of rapid decline of soil p H in hills and areas alongside rivers. The input of chemical fertilizer was negatively correlated with the change of soil p H. In 2005, the input of chemical fertilizer was about 505300 tons, increased by 2.42 times comparing with the input in 1984. From 2005 to 2014, the input of chemical fertilizer showed a steady trend, which was consistent with the trend of soil p H in these 30 years. The average soil p H in vegetable protected house was lower than that in the surrounding wheat field by 1.5–2 units,which indicated that the types of land use also affected soil p H. In general, the influencing factors were land use types and soil parent materials, and the factors of influencing temporal distribution of p H were fertilization and acid rain. Both acid rain and fertilization were the important driving factors of soil acidification.【Conclusions】The arable land soil p H in the study area showed an acidification tendency during 1984–2014.The spatial distribution of soil p H in the study area was mainly influenced by the parent materials of soil, soil types, content of soil organic matter, and the temporal distribution of soil p H in the study area was influenced by acid rain, fertilization and land use type. Acid rain and fertilization were the main factors causing soil acidification.
【Objectives】Soil p H is an important index to measure quality of cultivated lands. The influence of cropping system, cultivation system, rainfall and fertilization practices on soil acidification over the last 30 years was investigated.【Methods】This study investigated soil p H, soil parent material, soil type, soil organic matter content in 1984, 1994, 2005 and 2014, and the cultivation system, cropping system, rainfall, types of fertilizer application and their inputs in these years. The data came from 16996 sampling points in Yangzhou City,including 4107 agricultural chemical soil samples of the second general soil survey in 1984, 2862 general soil survey points in 1994, 4018 soil nutrients survey points in 2005, and 6009 soil nutrients survey points in 2014.Referencing to Chinese Soils, we classified the soil p H into five grades:Ⅰ(> 7.5), Ⅱ(6.5–7.5), Ⅲ(5.5–6.5), Ⅳ(4.5–5.5), and Ⅴ(< 4.5). The method of Kriging and relevant statistical methods in geostatistics were used in this study, and Arc GIS 10.1 and SPSS19 were used as tools for analyzing data.【Results】The results showed that the average soil p H was 7.51, 7.07, 6.83 and 6.74 respectively in 1984, 1994, 2005 and 2014. The spatial distribution of p H in the four periods was relatively constant, i.e. Lixiahe area > Yangtze River diked area > Sandy soil area in Tongnan > Hilly region. In 1984, 1994 and 2005,the soil p H mainly belonged to Grade I and II, which accounted for more than 90% of total area in 1984 and decreased to 75% in 1994 and 2005; in 2004, the soil p H mainly belonged to Grade Ⅱ and Ⅲ, which accounted for 65.7% of total area. In 30 years, soil p H was significantly decreased, 47.2% areas decreased by 0–1 unit and 39.3% areas decreased by more than 1 unit. In the first 20 years, soil p H was obviously declined and over 80% area soil p H declined by 0–2 units. The overall soil p H of different soil parent materials and soil varieties decreased by 0.9 unit and 0.8 unit, respectively.There was a negative correlation between changes of soil organic and p H. The average content of soil organic matter was increased by 6.01g/kg, it was one of the reasons for the decrease of soil p H as a whole. The p H value of the rainfall in this city decreased, especially rapid for the hills and areas alongside the river. This was consistent with the view of rapid decline of soil p H in hills and areas alongside rivers. The input of chemical fertilizer was negatively correlated with the change of soil p H. In 2005, the input of chemical fertilizer was about 505300 tons, increased by 2.42 times comparing with the input in 1984. From 2005 to 2014, the input of chemical fertilizer showed a steady trend, which was consistent with the trend of soil p H in these 30 years. The average soil p H in vegetable protected house was lower than that in the surrounding wheat field by 1.5–2 units,which indicated that the types of land use also affected soil p H. In general, the influencing factors were land use types and soil parent materials, and the factors of influencing temporal distribution of p H were fertilization and acid rain. Both acid rain and fertilization were the important driving factors of soil acidification.【Conclusions】The arable land soil p H in the study area showed an acidification tendency during 1984–2014.The spatial distribution of soil p H in the study area was mainly influenced by the parent materials of soil, soil types, content of soil organic matter, and the temporal distribution of soil p H in the study area was influenced by acid rain, fertilization and land use type. Acid rain and fertilization were the main factors causing soil acidification.
引文
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[3]Black A S.Soil acidification in urine-and urea affected soil[J].Australian Journal of Soil Research,2002,30:989-999.
[4]胡宁,娄翼来,张晓珂,等.保护性耕作对土壤交换性盐基组成的影响[J].应用生态学报,2010,21(6):1492-1496.Hu N,Lou Y L,Zhang X K,et al.Effects of conservation tillage on the composition of soil exchangeable base[J].Chinese Journal of Applied Ecology,2010,21(6):1492-1496.
[5]苏有健,王烨军,张永利,等.不同植茶年限茶园土壤p H缓冲容量[J].生态学报,2014,25(10):2914-2918.Su Y J,Wang Y J,Zhang Y L,et al.Soil p H buffer capacity of tea garden with different planting years[J].Chinese Journal of Applied Ecology,2014,25(10):2914-2918.
[6]王志刚,赵永存,廖启林,等.近20年来江苏省土壤p H值时空变化及其驱动力[J].生态学报,2008,28(2):720-727.Wang Z G,Zhao Y C,Liao Q L,et al.Spatial-temporal variation and associated affecting factors of soil p H in the past 20 years of Jiangsu Province,China[J].Acta Ecologica Sinica,2008,28(2):720-727.
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[8]曾招兵,曾思坚,刘一锋,等.1984年以来广东水稻土p H变化趋势及影响因素[J].土壤,2014,(4):732-736.Zeng Z B,Zeng S J,Liu Y F,et al.Change tendency of paddy soil p H in Guangdong Province since 1984 and influential factors[J].Soils,2014(4):732-736.
[9]邵学新,黄标,顾志权,等.长三角经济高速发展地区土壤p H时空变化及其影响因素[J].矿物岩石地球化学通报,2006,25(2):143-149.Shao X X,Huang B,Gu Z Q,et al.Spatial-temporal variation of p Hvalues of soils in a rapid economic developing area in the Yangtze River delta region and their causing factors[J].Bulletin of Mineralogy Petrology and Geochemistry,2006,25(2):143-149.
[10]张永春,汪吉东,沈明星,等.长期不同施肥对太湖地区典型土壤酸化的影响[J].土壤学报,2010,47(3):465-472.Zhang Y C,Wang J D,Shen M X,et al.Effects of long-term fertilization on soil acidification in Taihu Lake region,China[J].Acta Pedologica Sinica,2010,47(3):465-472.
[11]周晓阳,徐明岗,周世伟,等.长期施肥下我国南方典型农田土壤的酸化特征[J].植物营养与肥料学报,2015,21(6):1615-1621.Zhou X Y,Xu M G,Zhou S W,et al.Soil acidification characteristics in southern China’s croplands under long-term fertilization[J].Journal of Plant Nutrition and Fertilizer,2015,21(6):1615-1621.
[12]孟红旗,刘景,徐明岗,等.长期施肥下我国典型农田耕层土壤的p H演变[J].土壤学报,2013,50(6):1109-1116.Meng H Q,Liu J,Xu M G,et al.Evolution of p H in soils of typical Chinese croplands under long-term fertilization[J].Acta Pedologica Sinica,2013,50(6):1109-1116.
[13]Barak P,Jobe B O,Krueger A R,et al.Effects of long-term soil acidification due to nitrogen fertilizer inputs in Wisconsin[J].Plant and Soil,1997,197(1):61-69.
[14]徐仁扣,Coventry D R.某些农业措施对土壤酸化的影响[J].农业环境保护,2002,21(5):385-388.Xu R K,Coventry D R.Soil acidification as influenced by some agricultural practices[J].Agro-environmental Protection,2002,21(5):385-388.
[15]Covaleda S,Pajares S,Gallardo J F,et al.Effect of different agricultural management systems on chemical fertility in cultivated tepetates of the Mexican transvolcanic belt[J].Agriculture,Ecosystems&Environment,2009,129(4):422-427.
[16]Zhang H M,Wang B R,Xu M G,et al.Crop yield and soil responses to long-term fertilization on a red soil in Southern China[J].Pedosphere,2009,19(2):199-207.
[17]Malhi S S,Nyborg M,Goddard T,et al.Long-term tillage straw and N rate effects on some chemical properties in two contrasting soil types in Western Canada[J].Nutrient Cycling in Agroecosystems,2011,90(1):133-146.
[18]Malhi S S,Nyborg M,Harapiak J T.Effects of long-term N fertilizerinduced acidification and liming on micronutrients in soil and in bromegrass hay[J].Soil and Tillage Research,1998,48(1/2):91-101.
[19]Schroder J L,Zhang H,Girma K,et al.Soil acidification from longterm use of nitrogen fertilizers on winter wheat[J].Soil Science Society of America Journal,2011,75(3):957-964.
[20]Mc Andrew D W,Malhi S S.Long-term N fertilization of a solonetzic soil:Effects on chemical and biological properties[J].Soil Biology&Biochemistry,1992,24(7):619-623.
[21]鲁如坤.土壤农业化学分析方法[M].北京:中国农业科技出版社,2000.Lu R K.Analytical methods for soil and agro-chemistry[M].Beijing:China Agricultural Science and Technology Press,2000.
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[23]Medyńska-Juraszek A.Composition and activity of the microbial communities in forest floor exposed to deposition from copper industry[A].Conference of ecology of soil microorganisms.Microbes are important drivers of soil processes[C].Prague,Czech Republic,2011:9.
[24]Adams T M,Adams S N.The effects of liming on soil p H and carbon contained in the soil biomass[J].Journal of Agricultural Science,1983,101(3):553-558.
[25]Motavalli P P,Palm C A,Parton W J,et al.Soil p H and organic Cdynamics in tropical forest soils:Evidence from laboratory and simulation studies[J].Soil Biology&Biochemistry,1995,27(12):1589-1599.
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[30]惠学香.扬州地区酸雨现状及成因分析[J].环境监控与预警,2013,5(1):43-46.Hui X X.Analysis on the situation and cause of the acid rain in Yangzhou area[J].Environmental Monitoring and Forewarning,2013,5(1):43-46.
[2]Bedrna Z.Resistibility of landscape to acidification[J].Ekologia,2007,13:77-86.
[3]Black A S.Soil acidification in urine-and urea affected soil[J].Australian Journal of Soil Research,2002,30:989-999.
[4]胡宁,娄翼来,张晓珂,等.保护性耕作对土壤交换性盐基组成的影响[J].应用生态学报,2010,21(6):1492-1496.Hu N,Lou Y L,Zhang X K,et al.Effects of conservation tillage on the composition of soil exchangeable base[J].Chinese Journal of Applied Ecology,2010,21(6):1492-1496.
[5]苏有健,王烨军,张永利,等.不同植茶年限茶园土壤p H缓冲容量[J].生态学报,2014,25(10):2914-2918.Su Y J,Wang Y J,Zhang Y L,et al.Soil p H buffer capacity of tea garden with different planting years[J].Chinese Journal of Applied Ecology,2014,25(10):2914-2918.
[6]王志刚,赵永存,廖启林,等.近20年来江苏省土壤p H值时空变化及其驱动力[J].生态学报,2008,28(2):720-727.Wang Z G,Zhao Y C,Liao Q L,et al.Spatial-temporal variation and associated affecting factors of soil p H in the past 20 years of Jiangsu Province,China[J].Acta Ecologica Sinica,2008,28(2):720-727.
[7]郭治兴,王静,柴敏,等.近30年来广东省土壤p H值的时空变化[J].应用生态学报,2011,22(2):425-430.Guo Z X,Wang J,Chai M,et al.Spatiotemporal variation of soil p Hin Guangdong Province of China in past 30 years[J].Chinese Journal of Applied Ecology,2011,22(2):425-430.
[8]曾招兵,曾思坚,刘一锋,等.1984年以来广东水稻土p H变化趋势及影响因素[J].土壤,2014,(4):732-736.Zeng Z B,Zeng S J,Liu Y F,et al.Change tendency of paddy soil p H in Guangdong Province since 1984 and influential factors[J].Soils,2014(4):732-736.
[9]邵学新,黄标,顾志权,等.长三角经济高速发展地区土壤p H时空变化及其影响因素[J].矿物岩石地球化学通报,2006,25(2):143-149.Shao X X,Huang B,Gu Z Q,et al.Spatial-temporal variation of p Hvalues of soils in a rapid economic developing area in the Yangtze River delta region and their causing factors[J].Bulletin of Mineralogy Petrology and Geochemistry,2006,25(2):143-149.
[10]张永春,汪吉东,沈明星,等.长期不同施肥对太湖地区典型土壤酸化的影响[J].土壤学报,2010,47(3):465-472.Zhang Y C,Wang J D,Shen M X,et al.Effects of long-term fertilization on soil acidification in Taihu Lake region,China[J].Acta Pedologica Sinica,2010,47(3):465-472.
[11]周晓阳,徐明岗,周世伟,等.长期施肥下我国南方典型农田土壤的酸化特征[J].植物营养与肥料学报,2015,21(6):1615-1621.Zhou X Y,Xu M G,Zhou S W,et al.Soil acidification characteristics in southern China’s croplands under long-term fertilization[J].Journal of Plant Nutrition and Fertilizer,2015,21(6):1615-1621.
[12]孟红旗,刘景,徐明岗,等.长期施肥下我国典型农田耕层土壤的p H演变[J].土壤学报,2013,50(6):1109-1116.Meng H Q,Liu J,Xu M G,et al.Evolution of p H in soils of typical Chinese croplands under long-term fertilization[J].Acta Pedologica Sinica,2013,50(6):1109-1116.
[13]Barak P,Jobe B O,Krueger A R,et al.Effects of long-term soil acidification due to nitrogen fertilizer inputs in Wisconsin[J].Plant and Soil,1997,197(1):61-69.
[14]徐仁扣,Coventry D R.某些农业措施对土壤酸化的影响[J].农业环境保护,2002,21(5):385-388.Xu R K,Coventry D R.Soil acidification as influenced by some agricultural practices[J].Agro-environmental Protection,2002,21(5):385-388.
[15]Covaleda S,Pajares S,Gallardo J F,et al.Effect of different agricultural management systems on chemical fertility in cultivated tepetates of the Mexican transvolcanic belt[J].Agriculture,Ecosystems&Environment,2009,129(4):422-427.
[16]Zhang H M,Wang B R,Xu M G,et al.Crop yield and soil responses to long-term fertilization on a red soil in Southern China[J].Pedosphere,2009,19(2):199-207.
[17]Malhi S S,Nyborg M,Goddard T,et al.Long-term tillage straw and N rate effects on some chemical properties in two contrasting soil types in Western Canada[J].Nutrient Cycling in Agroecosystems,2011,90(1):133-146.
[18]Malhi S S,Nyborg M,Harapiak J T.Effects of long-term N fertilizerinduced acidification and liming on micronutrients in soil and in bromegrass hay[J].Soil and Tillage Research,1998,48(1/2):91-101.
[19]Schroder J L,Zhang H,Girma K,et al.Soil acidification from longterm use of nitrogen fertilizers on winter wheat[J].Soil Science Society of America Journal,2011,75(3):957-964.
[20]Mc Andrew D W,Malhi S S.Long-term N fertilization of a solonetzic soil:Effects on chemical and biological properties[J].Soil Biology&Biochemistry,1992,24(7):619-623.
[21]鲁如坤.土壤农业化学分析方法[M].北京:中国农业科技出版社,2000.Lu R K.Analytical methods for soil and agro-chemistry[M].Beijing:China Agricultural Science and Technology Press,2000.
[22]熊毅,李庆逵.中国土壤(第二版)[M].北京:科学出版社,1990:433-443.Xiong Y,Li Q K.The soils of China(2nd edition)[M].Beijing:Science Press,1990:433-443.
[23]Medyńska-Juraszek A.Composition and activity of the microbial communities in forest floor exposed to deposition from copper industry[A].Conference of ecology of soil microorganisms.Microbes are important drivers of soil processes[C].Prague,Czech Republic,2011:9.
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