摘要:
氮素是构成一切生命体的重要元素。在作物生产中，作物对氮的需要量较大，土壤供氮不足是引起农产品产量下降和品质降低的主要限制因子。本研究运用半微量开氏法测定了滇池流域高新区马金铺、晋宁县上蒜镇、盘龙江松华坝、呈贡县斗南村四个县区的自然村的土壤和植物全氮含量，揭示滇池流域全氮的分布特征。结果表明：采样地区土壤全氮含量的范围是0.23 g/kg~3.97 g/kg，平均值为2.35 g/kg，在此范围内得出不同土地利用方式下土壤平均全氮含量：耕地 > 林地；不同种植模式下土壤平均全氮含量：大棚 > 传统。采样地区作物全氮含量的范围为9.77 g/kg~46.77 g/kg，平均值为25.74 g/kg，在此范围内得出不同过渡区作物平均全氮含量：坝平地 > 水源地 > 坡耕地；不同区域作物平均全氮含量：高新区马金铺 > 盘龙江松华坝 > 呈贡县斗南镇 > 晋宁县上蒜镇。对土壤和农作物全氮含量做双变量相关性双尾检验，Pearson相关性指数为0.559，分析表明，农作物全氮含量与土壤中的全氮含量相关。
Abstract: Nitrogen is the essential element of all living organisms. Nitrogen is necessary for crop producing, and absence of Nitrogen in the soil is a major limited factor to lead the decreasing of crops gross production and property. Meanwhile, over fertilization with Nitrogen will cause eutrophication in the limnological ecosystem, accumulation of NO3-N to ground water, and poison damage. This ex-periment assayed the total nitrogen content in the soil and crops in four different regions, Dounan Town in Chenggong County, Shangsuan Town in Jinning County, Songhua Dam in Panlong District and Majinpu in High-Tech District, by semi-micro Kieldahl method to indicate the characteristic of the distribution of total Nitrogen in Dianchi Lake. The results demonstrate the total nitrogen con-tent in the soil in the sampling region is from 0.23 g/kg to 3.97 g/kg, and the mean is 2.35 g/kg. Meanwhile, the average total nitrogen content in the soil of cultivated land is higher than the woodland by the different land-using method. Furthermore, the average content of total nitrogen by green house growing is higher than the traditional growing method. The total Nitrogen content of crops in sampling region is from 9.77 g/kg to 46.77 g/kg, and the mean is 25.74 g/kg. In this range, the average total nitrogen content of transition regions crops varied as the following sequence: flat-farmland > sloped cultivated farmland > waterhead area farmland. In addition, and the total nitrogen content of crops in sampling regions varied as the following sequence: Majinpu in High-tech District > Songhua Dam in Panlong District > Dounan Town in Chenggong County > Shangsuan Town in Jinning County. The correlation coefficient of Pearson is 0.559 due to the two- way ANOVA test of the total nitrogen content in soil and crops, and according to the data analysis, the correlation of the total nitrogen content in crops and soils is significant.