不同轮作方式对黔产半夏土壤机械组成与养分含量的影响

Soil Textures and Nutrient Contents of Pinellia in Guizhou as Influenced by Different Rotations

本研究于2013年以4种轮作方式[半夏分别与太子参、何首乌(三年生)、金荞麦(短柱型)、苦参(一年生)轮作]土壤作为对象,分别运用简易比重计法、电位法、油浴加热重铬酸钾氧化容量法、凯氏蒸馏法、高氯酸消解-钼锑抗比色法、氢氧化钠熔融-火焰光度计法,测定了土壤机械组成、p H及有机质、全氮、全磷、全钾含量。结果表明,半夏分别与太子参、何首乌(三年生)、苦参(一年生)轮作土壤质地均为中壤土,物理性粘粒的含量分别为37.60%、44.60%、33.93%,与金荞麦(短柱型)轮作土壤质地为轻壤土,物理性粘粒的含量为31.10%。土壤p H值无显著差异,半夏与金荞麦(短柱型)轮作土壤有机质、全磷、全钾、全氮含量最高。细砂与土壤有机质含量显著正相关,粗粉砂与土壤有机质、全磷、全氮含量显著正相关,细粉砂与土壤有机质、全磷、全氮含量显著负相关,粘粒、物理性粘粒与土壤有机质为极显著负相关,与全氮含量为显著负相关。细砂、粗粉砂对土壤有机质含量的相对贡献率分别为35.91%、64.09%。综合考虑,半夏与金荞麦(短柱型)轮作在4种方式中最优。

Four kinds of crop rotation soils including Radix Pseudostellariae, triennial Polygonum multiflorum, the short column type of Fagopyrum cymosum and annual Sophora flavescens were used as Materials. Simple hydrometer method potentiometry, oil bath heatingoxidized by potassium dichromate volumetric method, Kjeldahl method, perchloric acid digestion and Mo sb colorimetry, sodium hydroxide molten-Flamephotometric method were respectively used to test soil mechanical composition, pH, organic matter, total nitrogen, total phosphorus and total potassium con- tents. The results showed that, in the radix pseudostellariae, fleece-flower root rotation （ three years old） soil, Sophora flavescens （annual） rotation soil texture was medium loam, the physical clay content were 37.60% , 44.60% , 33.93%, reepectively, and in the gold buckwheat （short column type） rotation soil texture was sandy loam,with its physical clay content 31.10%. There is no significant difference between pH values. The content of organic matter, total phosphorus,total potassium, total nitrogen content in the rotation soil pinellia tuber and Fagopyrum cymosum （short column type） soil were all highest. Fine sand （diameter O. 05 -0.25mm） had significantly positive correla- tion with organic matter, meanwhile ,coarse silt （diameter 0.01 -O. 05mm） also had significantly positive correla- tion with organic matter, total nitrogen and total phosphorus. In contrast, fine sand （0. 001 - 0. 005mm） was nega- tively correlated with organic matter. Furthermore, clay （ diameter 〈 0. 001 mm ）, physical clay （ diameter 〈 0. 01 mm） were extremely negatively correlated with organic matter, and correlated with total phosphorus. The rela- tive contribution to the content of soil organic matter by fine sand and coarse silt was 35.91% ,64.09% respectivety. After comprehensive consideration of the result, the crop rotations of pinellia tuber and Fagopyrum cymosum （short column type） were the most optimal in the four ways above.