| The soil nutrient of arable land is the basis of agricultural production.In recent years,along with the agricultural production and consumption,soil nutrient content is decreased,and the man-made land management mode and the single kind of fertilization have had complicated effects on soil nutrient status,it is urgent to research and analyze those different soil nutrient status,in order to guide the subsequent nutrient management and the protection of agricultural production.The traditional soil management methods are time-consuming,laborious and inefficient,and the data updating is slow.The traditional soil management methods are time-consuming,laborious and inefficient,and the data updating is slow.The management based on GIS soil database has become the focus of soil research.Therefore,based on the soil nutrient data at county level,this paper constructs the provincial soil nutrient database,which can provide the scientific basis for the management and sustainable utilization of the regional arable land soil nutrients.Shandong is a major agricultural province,as one of the five pilot provinces of country’s arable land fertility evaluation,has carried out a large number of soil survey and management work,but all of the previous studies are confined to the county level,lack of support for the provincial soil management,and the cost of rebuilding the Shandong provincial soil nutrients data base is too great to afford.This paper discusses the key technologies of the construction of the provincial scale arable land soil nutrient database,and provides reference for other provinces to build provincial soil database based on available data.In Shandong Province,it has been nearly 40 years since the second national general investigation,the soil nutrient status had been dramatically changed,those previous soil nutrient data cannot meet the current management of agricultural production for soil nutrients,the spatial variability of soil nutrient needs further study.This essay based on the arable land soil nutrient database in Shandong Province,and research on classification of the soil nutrient spatial variability and distribution,and provides the basis for the management partition of different nutrients.The spatial variability of soil nutrients affected by structural factors and random factors,the influence factors of soil nutrient in each region conducted a lot of research,but the study found that the scale has obvious effect of various factors on the strength,make the conclusion of the studies varies from different regions and cannot be used for reference,and even some conclusions are completely opposite,the change of scale level analysis of various factors affecting soil nutrient needs further study.In this paper,take the organic matter as an example,analyzed the scale’s influence of the strength of effect of those five kinds of influence factors such as landform types,the average annual precipitation,soil type,irrigation times,farming methods on the spatial variability of soil organic matter,provided reference for the scale effect of other nutrient spatial variability research,systematically describes the influence of the change of the efficiency of different factors of different scales.This study is based on the soil data of 135 counties in Shandong Province,constructed arable land soil nutrient database of Shandong Province,and based on the soil nutrient database,analyzed the spatial variation and soil nutrient status,discussed the Countermeasures of nutrient fertilization management.Take the organic matter as an example,analyzed the scale’s influence of the strength of effect of different influence factors s on the spatial variability of soil organic matter,furthermore,the weaken influence of scale on the influence factors is further studied.Results are showed as follow:(1)Shandong province statistics research showed that soil nutrients,organic matter,pH,potassium,potassium,phosphorus,iron,manganese,effective Mo has a strong spatial correlation,which mainly affected by structural factors;spatial correlation of total nitrogen,available Cu and available Zn,available boron and sulfur with moderate intensity,influenced by structural factors and random factors.(2)The distribution of soil nutrients in Shandong province is divided into five types: effective and effective with iron content showed a decreased gradually from the southeast coast to the northwest trend;pH and effective boron content gradually from west to East,from north to South gradually decreased;the higher the spatial correlation of soil organic matter,total nitrogen,potassium,available potassium and available phosphorus,which is similar to the spatial distribution of organic matter and total nitrogen,the content presented by the inland to the coast gradually decreased from north to south,first decreased then increased,available potassium and potassium decreased from west to East,gradually decreasing trend from the south to the north;the distribution of soil available zinc,available Cu and available molybdenum group space show massive distribution characteristics;effective sulfur content showed a low high trend around the middle.(3)In Shandong Province,the content of TN and AP and AK was highest in the gentle slope of landform,and was lowest in splay landforms;The distribution trend of TN and AP and AK in different soil types showed paddy soil >Sandy black soil>Cinnamon>Alluvial soil>Solonchaks;In different cultivated land condition,the content of TN and AP and AK was below average in dry land,the content of AP was below average in irrigable land.(4)The influence of spatial variability of soil organic matter affected by landform types,the average annual precipitation,soil type,irrigation times and cultivation mode of five kinds of factors: With the decrease of scale,the influence intensity of landform type and annual average precipitation on soil organic matter is enhanced,and the influence intensity of soil type decreases first and then increases.The influence of irrigation frequency and tillage methods on soil organic matter decreased little with scale.(5)Effects of intensity scale on structural factors weaken,the more great scale,weakening effect is stronger,weakens the random factors changing with the scale difference. |
