摘要
【目的】研究云贵高原地区烟田土壤肥力评价的尺度效应,为精准施肥和不同层级土壤管理决策提供科学依据。【方法】贵州省六盘水市钟山、水城和盘州3个烟区分别采集了100、180和220个典型烟田的耕层(0~20 cm)土样,选取pH、有机质(OM)、碱解氮(AN)、有效磷(AP)、速效钾(AK)、交换性镁(Mg^(2+))、水溶性氯(Cl^(-))、有效硼(B)和有效锌(Zn)9个肥力指标,分别基于市域(L,500个样点)尺度和烟区尺度(S,3个烟区各自样点),利用主成分分析法确定了各肥力指标的权重,采用加权和法计算了烟田土壤综合肥力指标(Integrated Fertility Index,IFI),采用简单克里格插值法形成了IFI空间分布图。【结果】①土壤肥力指标受烟区、环境变量(海拔、年均气温和降雨量)、土壤类型和成土母质的影响。不同尺度计算出的土壤肥力指标权重之间存在明显差异,土壤肥力指标权重的相对差异随样点数量的增加而升高。②L和S尺度下,3个烟区IFI均值大于0.5。钟山和盘州L尺度的IFI显著高于S尺度(P<0.05),水城无显著差异。在IFI较高级别以下(<0.6)范围内,3个烟区L尺度下的烟田数量均少于S尺度。③不同尺度下IFI的空间分布格局差异在不同烟区表现不同,相较于L尺度,S尺度下钟山东北部高值区(0.8~1)减少,西北部及东南部低值区(0~0.4)增加。水城和盘州分布格局较相似,水城S尺度下的图斑更为破碎,盘州S尺度下中值区(0.4~0.6)面积增加。④样点数量和密度影响着烟区L和S尺度下IFI的图斑数量差异,样点越多,越适合采用L尺度进行评价。【结论】云贵高原烟田土壤肥力评价过程存在明显的尺度效应,进行土壤肥力评价应考虑空间尺度,明确土壤肥力空间分异,服务于精准施肥和土壤改良。
[Objective]The aims were to study the scale effects on soil fertility assessment in tobacco fields in Yunnan-Guizhou Plateau,so as to provide scientific basis for precise fertilization and different soil management decisions.[Method]Soil samples of plough layers(0-20 cm)of 100,180 and 220 typical tobacco fields were collected respectively in Zhongshan,Shuicheng and Panzhou regions of Liupanshui city,Guizhou Province in Yunan-Guizhou Plateau.Nine fertility indicators including pH,organic matter(OM),alkali-hydrolyzed nitrogen(AN),available phosphorus(AP),rapid available potassium(AK),water-soluble chlorine(Cl^(−)),exchangeable magnesium(Mg^(2+)),available boron(B)and available zinc(Zn)were determined.Based on the scale of the whole city(L scale,all 500 samples)and the scale of the 3 tobacco-growing area(S scale,samples of each region),the weights of fertility indicators were determined by principal component analysis(PCA),soil integrated fertility index(IFI)was calculated by weighted sum method,and the spatial distribution of IFI was formed by the interpolation method of simple kriging.[Result]①Soil fertility indicators were affected by the region,environmental variables(altitude,annual mean temperature and precipitation),soil type and parent material.There were significant differences between the weights of soil fertility indicators calculated at different scales.The relative differences in weights of fertility indicators were increased with the increase of the number of tobacco fields.②At L and S scales,the mean IFI of the three regions were all higher than 0.5.IFI of L scale in Zhongshan and Panzhou were significantly higher than that of S scale(P<0.05),but no significant difference was found in IFI at L and S scales in Shuicheng.Below the higher level of IFI(<0.6),the number of tobacco fields at L scale was less than that at S scale.③At L and S scales,the spatial distribution of IFI was different in different regions.Compared with L scale,for Zhongshan,the high IFI region(0.8-1)in the northeast was decreased while the low IFI region(0-0.4)in the northwest and southeast was increased at S scale.For Shuicheng and Panzhou,the spatial distribution of IFI was similar at L and S scales,but the pattern of IFI was more fragmented at S scale in Shuicheng,and the area of the median region(0.4-0.6)at S scale in Panzhou.④The number or density of samples affected the difference of map-spot numbers at L and S scales.The more samples and the more suitable L scale were for evaluation,which could better reflect the spatial differentiation of IFI and were beneficial to guide the precise fertilization and soil improvement.[Conclusion]Soil fertility evaluation in Yunnan-Guizhou Plateau has obvious scale effect,and the spatial scale should be considered in soil fertility evaluation so as to reveal the spatial differentiation of soil fertility.It could serve for precision fertilization and soil improvement.
作者
孙正
吴华勇
王德彩
李德成
刘峰
SUN Zheng;WU Hua-yong;WANG De-cai;LI De-cheng;LIU Feng(State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;University of the Chinese Academy of Sciences,Beijing 100049,China;College of Forestry,Henan Agricultural University,Zhengzhou 450003,China)
出处
《土壤通报》
CAS
CSCD
北大核心
2023年第4期800-811,共12页
Chinese Journal of Soil Science
基金
中国烟草总公司贵州省公司重点研发项目(2021XM20)资助。
关键词
土壤肥力
评价
尺度效应
土壤空间变异
Soil integrated fertility
Assessment
Scale effect
Soil spatial variation