Temporal and spatial variation characteristics of soil moisture

The temporal and spatial variations of soil moisture are analyzed using in-situ soil moisture data from 98 agricultural meteorological gauge stations in Eastern China for the years 1981 - 1991. The data includes gravimetric soil moisture, field capacity, bulk density of soil and wilting level. Distributions of gauge stations for soil moisture measurement are shown by Fig. 7.3, in which F represents non irrigation and T for irrigation. Irrigation stations will not be used in analysis in order to remove the influence of human activity. Soil types of gauge stations are mainly loamy and sandy loamy soils (as shown in Fig. 7.4,). 12 sub-regions were divided in Eastern China according to soil and soil moisture characteristics (Table 7.1). Field capacity, bulk density and wilting level were regarded as constant in each region.

Fig. 7.2 Distributions of gauge stations for soil moisture measurement in China

8CTE 9CFE 100E 11CTE 12ffE 130°E

8CTE 9CFE 100E 11CTE 12ffE 130°E

Table 7.1 12 small regions

No. Latitude and longitude

2 40" N < lat < 44" N, lon > 124" E

4 40" N < lat < 44" N,114" E < lon < 124" E

5 lat > 36"N , 100"E < lon < 114"E

6 28" N < lat < 36" N ,100" E < lon < 106" E

7 lat < 28" N , 100" E < lon < 104" E

8 30" N < lat < 40" N, lon > 114" E

9 28" N < lat < 36" N ,106" E < lon < 114" E

10 lat < 28" N , 104" E < lon < 110" E

12 lat < 28" N ,110" E < lon < 114" E

Fig. 7.3 Distributions of gauge stations for soil moisture measurement in Eastern China (F represents non irrigation and T for irrigation)
Fig. 7.4 Soil types of gauge stations(c: clay, l: loam, s: sand, sl: sandy loam)
0 0

Post a comment