Spatial Variability of Crop Yield as a Stochastic Soil Process
1981
Bresler, Eshel | Dasberg, S. | Russo, D. | Dagan, G.
In a heterogeneous field in which the soil water properties vary, the yield of a crop may also differ from point to point. Using actual field variability data of irrigated peanut (Arachis hypogaea L.) yield, of soil water properties, and stochastic approaches, effects of spatial variability of soil water on the crop yield distribution and on the spatial correlation structures are evaluated. Values of total dry matter yield (YT) [together with two additional crop yield components pods (Yₚ) and hay (Yₕ)], soil water content [before (θb) and after (θₐ) irrigation], and saturated conductivity, Kₛ, were used to estimate distribution types (normal or lognormal) and their moments. The two-point autocorrelation functions of YT, Yₚ, Yₕ, θₐ, θb, and Kₛ, were calculated and used to estimate their integral scales (J). The calculated J-values for Kₛ, θₐ and θb, and YT are 25, 21, and 13 m, respectively. These results and calculations of the cross correlations between crop yield and soil water components were used to establish an approximate relationship between the crop yield and the soil water variables regarded as random spatial variables.
显示更多 [+] 显示较少 [-]