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耕地土壤养分调查数据表明,天津地区土壤有机质、全氮、全磷、全钾、速效氮、速效磷、速效钾总体呈逐年增加的趋势,土壤微量元素呈下降的趋势。2003年与1981年比较,土壤有机质、全氮、速效磷、速效钾分别增加26.39%,7.95%,404.26%,28.44%,而土壤有效铜、有效锰、有效锌分别降低了55.87%,21.25%,65.83%。土壤有效铜、有效锰已经低于或接近土壤临界值;土壤有效铁、锌、硼、钼等微量元素还较丰足。
The data of soil nutrient survey in cultivated land show that soil organic matter, total nitrogen, total phosphorus, total potassium, available nitrogen, available phosphorus and available potassium are all increasing year by year in Tianjin, and trace elements in soil tend to decline. Compared with 1981, soil organic matter, total nitrogen, available phosphorus and available potassium increased by 26.39%, 7.95%, 404.26% and 28.44% respectively in 2003 and 2003, while soil available copper, available manganese and available zinc decreased by 55.87% and 21.25% , 65.83%. Soil available copper, available manganese has been below or near the critical value of the soil; soil available iron, zinc, boron, molybdenum and other trace elements are more abundant.