干热河谷石漠化区火龙果地不同耕作方式的土壤矿质元素特征

为探讨不同耕作方式的土壤矿质元素含量变化特征,促进火龙果生长发育和品质改良,该研究采用套种紫花苜蓿(Medicago sativa)、施用有机肥和化肥与农药、地膜覆盖和无措施五种耕作方式,以每种方式土壤的22种矿质元素为评价指标,比较不同耕作方式的矿质元素含量差异,阐明土壤矿质元素之间的相关关系。结果表明:(1)与无措施相比,其他耕作方式的Ca、Si、Mn等元素含量呈增加趋势,Fe、Mg、Al等元素含量则降低,Na含量无显著差异。(2)施用有机肥的矿质元素含量最丰富,地膜覆盖次之,套种紫花苜蓿最低。(3)相关性分析表明,火龙果地土壤矿质元素间多存在显著相关性,Al、Si、S、Ni与其他元素的相关性较密切,其次为Fe、Mg、Na、Mn、Cu和Co,均达到显著或极显著水平。(4) Ca、Fe、Mg、Mn、Cu、Zn和B之间多呈负相关,存在拮抗效应。干热河谷石漠化区在火龙果栽培时,应首选有机肥作为养分添加方式,并及时补充不同耕作方式造成的土壤矿质养分亏缺,尤其是Fe、Mg、Al、Na、Cu、Zn等元素。

Characteristics of soil mineral elements in different tillage methods of pitaya in dry-hot valley rocky desertification region

Changing characteristics of soil mineral elements in different tillage methods were discussed in order to promote growth, development and quality improvement of pitaya. The evaluating indicator was conducted on 22 soil mineral elements in five tillage methods of pitaya land, the methods include interplant alfalfa(Medicago sativa), application of organic fertilizer, chemical fertilizer and pesticides, film mulching and no measures in study area, to compare the content differences of soil mineral elements in different tillage methods, correlation analysis was also performed to clarify the correlation between mineral elements in soil. The results were as follows:(1)Compared with no measures, the content of Ca, Si, Mn et al. showed an increasing trend, while the content of Fe, Mg, Al et al. decreased, and that the content of Na showed no significant difference.(2)About the supplement of mineral elements, the organic fertilizers applied were the most abundant, the second was plastic mulching, alfalfa is the worst.(3)According to the correlation analysis, there were correlations among soil mineral elements. Al, Si, S and Ni were closely related to other elements, while Fe, Mg, Na, Mn, Cu and Co had significant or extremely significant correlation between elements.(4)Besides, there was an extremely significantly or significantly negative correlation between Ca, Fe, Mg, Mn, Cu, Zn and B, antagonistic effect. When cultivated of pitaya in dry-hot valley rocky desertification region, the tillage method of applying organic fertilizer is the first choice for nutrient supplement. The deficiency of mineral elements caused by different farming methods should be timely supplemented, especially for Fe, Mg, Al, Na, Cu, Zn et al.