|
|
|
| Spatial distribution of soil organic matter and total nitrogen in Matiyu small watershed in hilly area of middle southern Shandong Province |
| Geng Guangpo, Gao Peng, Lv Shengqiao, Zhang Jie |
| Forestry College of Shandong Agricultural University, Taishan Forest Ecosystem Research Station, Shandong Province Key Laboratory of Soil Erosion and Ecological Restoration, 271018, Tai'an, Shandong, China |
|
|
|
|
Abstract By analyzing the representativeness and operability of land use and sample points in general, samples from 97 sites (0-20cm) were collected during October 2010 in Matiyu small watershed in hilly area of middle southern Shandong Province. By employing regression-kriging methods and ‘3S’ technology, the spatial distribution characteristics of soil organic matter and total nitrogen were studied. Results showed: 1) The average values of surface soil organic matter and total nitrogen mass fraction were 20.45 and 1.18g/kg respectively, and the coefficients of variation were 27.68% and 27.97% respectively. Environmental factors included elevation, slope, aspect and NDVI had significant correlations with soil organic matter and total nitrogen, and elevation and cosine value of aspect performed the best among the selected factors. Moreover, the prediction accuracy of regression-kriging was better than that of ordinary kriging. 2) Semivariogram test showed that both regression values of soil organic matter and total nitrogen had strong spatial autocorrelation with the sill values 7.3% and 17.50% respectively. Both residual values of soil organic matter and total nitrogen had medium spatial autocorrelation with the sill values 33.93% and 25.58% respectively. 3) The distribution map of regression-kriging showed that both soil organic matter and total nitrogen mass fraction decreased from the southeast to the northwest, which was similar to the trend of DEM in Matiyu small watershed. The pattern of soil organic matter mass fraction could be ordered as Quercus acutissima plantation＞Pinus thunbergii plantation＞Vegetable field＞Zea mays field＞Castanea mollissima plantation＞Grassland. The soil total nitrogen mass fraction could be ordered as Quercus acutissima plantation＞Vegetable field＞Pinus thunbergii plantation＞Zea mays field＞Castanea mollissima plantation＞Grassland. At different elevations, the higher the elevation, the larger the soil organic matter and total nitrogen mass fraction, while at different aspects, the pattern of soil organic matter and total nitrogen mass fraction could be ordered as shady slope＞half-sunny slope＞sunny slope.
|
|
Received: 24 June 2011
|
|
|
|
|
|
|
