有机质对黄土善土持水性与水肥效应的影响

黄土高原南部台塬地区有机质对土壤含水量的影响试验研究表明土壤水势相等时,随着土壤有机质含量提高,土壤水分含量增加。土壤水分能量(土壤水势)水平不同,有机质对土壤水分含量的效应值不同,在土壤水势为-40～-50kPa时,有机质对土壤水分含量的效应值最大,土壤水势大于-40kPa小于-50kPa,有机质对土壤水分含量的效应值逐渐变小;在不同土壤含水量条件下,土壤肥力(土壤有机质含量)与水势呈显著负相关,其直线斜率值能更好反映土壤水肥效应状况,并随着土壤含水量的降低,土壤水肥效应值增大,在低肥力土壤中,增施有机肥土壤水肥效应值增加最为显著。

Effect on organic matter to the water retention capability and effect of water and fertility of Huangrang-soil

Based on the experiment, the results showed that: the organic matter have significant effect on soil water content, as the same soil water potential, soil moisture content increased, but at different level of energy of soil moisture(soil water potential), the value of the organic matter to soil moisture content was different. When the soil water potential was between-40 kPa and-50 kPa, the value of the organic matter to soil moisture content was biggest, and when soil water potential was more than-40 kPa or less than-50 kPa, the value of the organic matter to soil moisture content diminished. At different soil water content, the fertility of soil(soil organic matter content) showed negative related significantly, and the inclined rate in straight line value could reflect the effect of water and fertility of soil best. With the soil water content decreasing, the value of effect of water and fertility of soil increased, and in low fertility soil, increasing the application of organic fertilizer make the effect of water and fertility of soil most significant.