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Citrus fields are often found on the hillside slope in Japan because of its efficiency of solar energy density and natural drainage conditions.Soil mapping techniques are useful to visualize the variability of soil parameters and field conditions.On-line soil sensors have been developed, though the tractor-mounted sensors are not available for such steep slope fields.The study was conducted to describe the variability of soil parameters of the slope fields.A test field located in Iwagi Island, Ehime prefecture in the southwest region of Japan.The test was carried out in December 13, 2013, just after harvesting.The field size was 1200 m2.A hundred of soil samples with location data by an RTK-GPS were collected, and the sampling location was 1 m distance from the trunk of target tree.Soil sampling depth was20 cm.In-situ measurement of volumetric moisture content (VMC), EC and soil temperature was also carried out at depths of zero, 20 cm and 40 cm at the same location of soil sampling.The soil parameters analyzed and mapped were moisture content (MC), electrical conductivity (EC), pH, available phosphorus (P-a), exchangeable potassium (K), exchangeable magnesium (Mg), exchangeable calcium (Ca), magnesium/calcium ratio(Mg/Ca), calcium/potassium ratio(Ca/K), calcium saturation percentage (CSP), base saturation percentage (BSP), soluble cupper (Cu), soluble zinc (Zn), easily reducible manganese (Mn), hot water soluble boron (B), hot water extractable nitrogen (N-h), total nitrogen (N-t), nitrate nitrogen (N-n), ammonium nitrogen (N-a), PAC, CEC, humus content, bulk density (BD), exchangeable acidity.Results cluster analysis showed that the soil parameters were classified into 5 groups in convenience.Group1 had 2 parameters (Mg, Mg/K).Goup2 had2 parameters (BD, exchangeable acidity).Group3 had 8 parameter (pH, MC, PAC, pH, Ca/Mg, Ca, CSP, BSP, Zn).Group4 had 2 parameters (Cu, Mn).Group5 had 10 parameters (EC, N-a, B, N-h, N-t, humus content, N-n, K, P-a,CEC).