山东“蓝黄”两区耕层土壤有机质的时空分异特征

Spatial and temporal variation characteristics of soil organic matter in topsoil in the“blue and yellow”economic zones of Shandong Province

山东“蓝黄”经济区是国家重点规划建设区,为研究其耕层土壤有机质的时空变异特征,综合经典统计学、地统计学和GIS(地理信息系统)方法,对2005年与2017年两个时段的耕层(0~20 cm)土壤有机质进行时空分异研究,采用指示克里格法评估有机质缺乏的风险概率,进而研究县域间有机质的聚集特征并提出规划建议。结果显示:不同时期经济区的土壤有机质均具有中等的空间变异性和自相关性,变异系数在25.68%~35.46%之间,块基比在45.45%~55.01%之间。“蓝黄”两区2005—2017年有机质的年平均增速分别为0.21g·kg^(-1)和0.32 g·kg^(-1),2017年的平均有机质含量分别为14.65 g·kg^(-1)和16.04 g·kg^(-1),内陆平原区有机质含量高,山丘与滨海平原区有机质含量低。“蓝黄”两区有机质缺乏的风险概率较低,分别为0.21和0.14,两区有机质的空间聚集特征显著,限制建设区(高-高聚集型)与综合整治区(低-低聚集型)均以“组团”形式分布。研究发现,2005—2017年山东“蓝黄”两区的耕层有机质在时间上不断累积,空间上呈聚集分布,研究结果可为区域规划和农业可持续发展提供科学依据。

The“blue and yellow”economic zones are national key planning and construction areas in China.To study the spatiotemporal variation characteristics of soil organic matter(SOM)in the topsoil,classical statistics,geostatistics,and GIS methods were used to explore the spatiotemporal variation of soil organic matter in the plough layer(0~20 cm)in 2005 and 2017.The risk probability of organic matter deficiency was evaluated by the Kriging indicator,while the accumulation characteristics of organic matter among counties were studied and planning suggestions were put forward.The results showed that the soil organic matter had moderate spatial variability and autocorrelation in different periods,with a coefficient of variation ranging from 25.68%to 35.46%and C0(/C+C0)ranging from 45.45%to 55.01%.The annual average growth rates of organic matter from 2005 to 2017 in“blue and yellow”areas were 0.21 g·kg^(-1) and 0.32 g·kg^(-1),respectively,while the average organic matter contents were 14.65 g·kg^(-1) and 16.04 g·kg^(-1),respectively.The organic matter content in the inland plain was high,while that in the hilly and coastal plain was low.At the same time,the risk probabilities of organic matter deficiency were low,at 0.21 and 0.14,respectively.The spatial accumulation characteristics of organic matter in the“blue and yellow”areas were significant and the restricted construction area(H-H type)and comprehensive improvement area(L-L type)were distributed in the form of“clusters”.It was found that organic matter in the plough layer of“blue and yellow”areas accumulated in time and in space from 2005 to 2017,providing a scientific basis for regional planning and agricultural sustainable development.