乌蒙山区毕节市耕地土壤养分丰缺评价及其变化趋势

Evaluation of Nutrient Abundance and Deficiency and Change Trend of Cultivated Soil in Bijie of Wumeng Mountain Area

通过1∶50000耕地质量地球化学调查,获得了乌蒙山区毕节市耕地土壤养分指标的高精度分析数据。统计结果表明:有机质、N、P、Zn、Cu、Mo、速效磷、有效硼含量较贵州省高,而硼、碱解氮、速效钾、有效钼和有效锌含量较低;对比第二次土壤普查养分分级标准,P、B、Mo、Cu、Zn、有效锌含量丰富,有机质、N、碱解氮含量较丰富,K、有效钼、速效磷和速效钾含量中等,有效硼含量较缺乏;在不同酸碱性环境、土壤类型、耕地利用方式中土壤养分含量差异较大。评价结果显示:全市土壤酸化突出;有机质、N、P、B、Mo、Zn、Cu、碱解氮、速效磷、有效锌丰缺程度以中等及以上为主,而K、速效钾、有效硼、有效钼则以中等及以下为主;K较缺乏-缺乏是影响土壤养分综合质量的重要因素。对比第二次土壤普查结果,显示有机质、N、速效磷、有效锌含量水平显著提高,与长期施用氮肥、磷肥、锌肥及推广绿肥、有机肥等有关;而速效钾、有效钼、有效硼则显著降低,与钾、钼、硼肥施入量少、土壤酸化损失及农作物大量带走有关。因此,掌握耕地土壤养分丰缺程度及变化规律,进行酸碱度适宜改良和增施钾、钼、硼肥用量促进土壤养分平衡,进而为乌蒙山区发展山地特色农业提供依据。

The high precision data of soil nutrient index of cultivated land in Wumeng Mountain area of Bijie were obtained through 1∶50000 geochemical survey of cultivated land quality.The results showed that the contents of Organic matter, N, P, Zn, Cu, Mo, available phosphorus and available boron are higher than those of Guizhou province, while the contents of Boron, alkali-hydrolyzed Nitrogen, available Potassium, available Molybdenum and available Zinc are lower.Compared with the nutrient classification standard of the second soil survey, the content of P, B, Mo, Cu, Zn and available Zinc are rich, while the content of Organic matter, N and alkali-hydrolyzed Nitrogen are quite abundant, the content of K, available Molybdenum, available Phosphorus and available Potassium are moderate, and the content of available Boron is relatively deficient.The contents of soil nutrients in different acidic and alkaline environments, soil types and cultivated land use methods are different.The results showed that soil acidification is more prominent in the city.Organic matter, N, P, B, Mo, Zn, Cu, alkali-hydrolyzed Nitrogen, available Phosphorus, available Zinc abundance and deficiency degree are mainly medium or above, while K, available Potassium, available Boron and available Molybdenum are mainly medium or below.Lack of K is an important factor restricting the comprehensive quality of soil nutrients.The results of the second soil survey showed that the contents of Organic matter, N, available Phosphorus and available Zinc were significantly increased, which was related to the long-term application of Nitrogen fertilizer, Phosphate fertilizer and Zinc fertilizer, as well as the promotion of green fertilizer and Organic fertilizer.However, the available Potassium, effective Molybdenum and effective Boron were significantly reduced, which was related to the low application amount of Potassium, Molybdenum and Boric fertilizer, the loss of soil acidification and a large amount of taken away crops.Therefore, it is necessary to master the degree of soil nutrient abundance and deficiency in cultivated land and change the law, to provide a data support for improving the pH and increasing the amount of Potassium, Molybdenum and Borax fertilizer to promote the balance of soil nutrient, so as to provide a scientific basis for the development of characteristic mountain agriculture in Wumeng Mountain area.