The experiment was conducted to study the effects of plant community productivity, plant community and soil C:N:P ecological characteristics of chemometrics In hulunbuir Leymus Chinensis Mowing Meadow, by using different kinds of fertilization and different fertilizer treatment, in order to select the optimal combination of the grassland types and fertilizer rate for this region. Our objective was to explore the influence of nitrogen (N) and phosphorus (P) fertilizer levels on carbon C:N:P stoichiometry of plant community and soil with Leymus Chinensis Mowing Meadow. Our results showed that adding the concentration fertilizer reduced community biomass on the ground was on the rise in 2014 and H3 (N 10.5 g·m-2+P 5.1 g·m-2) has the highest biomass (505.8 g·m-2), but community biomass on the ground climbed up and then declined in 2015 and H2 (N 7.0 g·m-2+P 3.4 g·m-2) was the highest biomass (264 g·m-2). The total carbon, total nitrogen and total phosphorus of plant community had no marked change in 2014. It is opposite change tendency that C: P and N: P; Other indexes were not significant difference besides total N of H2 and H3, total P of H1 in 2014.In 2014, the change range of three layers of soil C:N and C, P and N:P is in fluenced by fertilization concentrations are relatively small, is respectively 18.31~19.42, 64.06~102.51 and 3.38~5.19. The change of the contrast ratio of 2 years, C:P and N:P in 2015 had decline about is 47.8%~59.7% and 15.0%~35.8%. It indicates that nitrogen element may be a major factor of limiting plant growth and phosphorus element can make the nutrient ratio in a relatively balanced state by the view of plant community and soil stoichiometric ratio in this region. The short-term fertilization for the region to ease restrictions on the nitrogen and phosphorus element, but too much nitrogen element added could lead to a change in limiting factor.%以呼伦贝尔羊草(Leymus chinensis)草甸天然割草场为研究对象,通过设置不同种类肥料和不同施肥量处理,探讨植物群落生产力、植物群落和土壤C:N:P生态化学计量学特征,试图筛选出适合该地区草地生长的施肥种类与施肥量的最优组合.结果表明:随着施肥水平的增加,2014年群落地上生物量呈上升趋势,H3(尿素10.5 g·m-2+过磷酸钙5.1 g·m-2)的生物量最高(505.8 g·m-2);2015年群落地上生物量先增加后减少,施肥水平H2(尿素7.0 g·m-2+过磷酸钙3.4 g·m-2)生物量最高(264 g·m-2).2014年和2015年不同施肥处理下植物群落C、N和P含量差异不显著.2014年不同处理间植物群落C:N差异显著,H3施肥水平的C:N(29.28)显著高于其他水平(P<0.05),而2015年C:N随着施肥水平的增加而增加;与C:N变化趋势完全相反,2014年、2015年群落的C:P和N:P均随施肥水平增加而减少.2014年与2015年不同处理下土壤全C、全N和全P中,除2014年0~10 cm土层H2和H3的全N、H1的全P显著高于其他处理(P<0.05),其他指标在不同处理间差异均不显著.2014年3层土壤的C:N、C:P和N:P受施肥量的影响相对较小,变化范围分别为18.31~19.42、64.06~102.51、3.38~5.19.2015年3层土壤的C:N、C:P和N:P变化范围为11.33~12.51、25.59~53.49、2.17~4.41.对比2年比值的变化,2015年C:P和N:P较2014分别下降了47.8%~59.7%和15.0%~35.8%.研究结果表明:从植物群落和土壤的化学计量比角度来看,N可能是本地区限制植物生长的一个主要因素,P处于相对平衡的状态,在未来的N、P混施管理中,需降低或不添加磷肥,适量添加N素,才能使群落呈现适中的化学计量比.
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