【作者】 林青慧；

【导师】 张维理；

【作者基本信息】 中国农业科学院 ， 植物营养学， 2004， 硕士

【摘要】 近年来，随着种植业结构调整力度的逐渐加大，我国农田种植模式有了很大的变化，而不同农田种植模式的施肥情况及养分平衡状况具有很大的差异，因此深入研究不同作物及不同种植模式的养分吸收规律、养分平衡状况及其环境效应对于指导农业生产、减少农业环境污染具有重要意义。本文通过对上海黄浦江上游水源保护区35个地块、37种种植作物的周年监测，对试区主要作物的养分吸收规律及主要种植模式的养分平衡状况进行了系统的研究，并综合降雨、气温、作物覆盖、养分盈余等多种因素对不同作物及不同轮作方式的环境效应进行了初步评价。主要研究结果如下： 在各茬作物的主要生育期取样，对茄果类、瓜类、豆类、叶菜类、苗木及其它几种常见作物N、P、K吸收特性进行了系统的研究，得出20种常见作物的养分吸收特性。 通过对黄浦江上游水源保护区23种蔬菜水果可食部位硝酸盐含量的分析得出：不同种类蔬菜可食部位硝酸盐含量差异很大，其高低顺序为非结球叶菜类＞根茎类＞葱蒜类＞结球叶菜类＞花菜类＞豆类＞茄果类＞瓜果类＞薯芋类；适当晚收可以降低蔬菜硝酸盐含量；随着氮肥施用量的增加，蔬菜可食部位硝酸盐含量升高。 不同种植模式对土壤速效养分含量具有明显的影响，0-90cm土壤NO₃^--N累积在主要种植模式中的排列顺序为：菜地(NO₃^--N215.13 kg．ha^-1)＞果园＞苗圃＞粮田(NO₃^--N 53.55kg．ha^-1)，与0-30cm土壤Olsen-P的含量顺序基本相同。不同土壤剖面N、P、K含量具有很大的差异，土壤中全氮、全磷、有机质、NO₃^--N、NH₄⁺-N、Olsen-P含量随土层深度的增加而下降，而速效钾含量随土层深度的增加略微上升。 不同种植模式养分平衡状况表现为：大田作物N盈余78.9kg．ha^-1，P₂O₅亏缺38.1kg．ha^-1，K₂O亏缺169.8kg．ha^-1。蔬菜作物N盈余181.1kg．ha^-1、P₂O₅盈余101.7kg．ha^-1，K₂O亏缺66.1kg．ha^-1，而果树的N、P、K均有盈余，分别为N404.7 kg．ha^-1、P₂O₅118.5 kg．ha^-1、K₂O147.0 kg．ha^-1。苗木N、P、K稍有盈余，但其N、P的盈余量比蔬菜、果树等经济作物小的多。 从轮作周年来看，不同轮作方式养分平衡状况差异很大。大田作物之间轮作呈现N盈余、P稍有盈余或基本平衡，K亏缺较严重的状况。蔬菜作物之间周年轮作平衡状况差异很大。 在本试验条件下，综合降雨、气温、作物覆盖、N、P总盈余、N、P天盈余等各种因素，对试区不同作物及不同种植模式的环境效应进行综合评价，并对试区每种监测作物及每种轮作方式的环境污染风险进行等级，将监测作物的环境污染风险分为4个等级，轮作的环境污染风险分为3个等级。综合对经济效益的分析，我们给出如下种植作物推荐，草皮、雪菜、香樟、含笑等可以在一级水源保护区内种植，毛豆、水稻、土豆、番茄、黄杨、丁香、豇豆等可以在准水源保护区内适量种植。更多还原

【Abstract】 In recent years, planting patterns of farmland in our country have changed greatly along with the adjustment of cropping system. While in different planting patterns the fertilizer application rate and nutrient balance differ a lot from each other. In order to guide agricultural production and decrease agricultural environmental pollution, the environmental effect and nutrient balance condition of different planting patterns are studied in this research. Totally 35 pieces of fields and 37 kinds of plants in the valley of Huangpujiang river in Shanghai are investigated. This work also studys the nutrient absorption law of main plants and the nutrient balance condition of main planting patterns in Shanghai. Rainfall and other meteorology condition are combinated in analysing the environmental effect of different planting patterns. The main result are as fellows:Sampling in main growing stage in every crop,this work studys the N,P,K absorption law of solanacecus fruit, gourd crop, leguminous vegetable, leaf vegetable, seedling and several other plants.The current situation of nitrate concentration of vegetable in Shanghai: the content of nitrate in vegetables varied significantly with different categories of vegetable species, the order is leaf vegetable>root vegetable>scallions>cauliflower>leguminous vegetable>solanacecus fruits>gourds crop> Chinese ram; late harvest can reduce nitrate concentration of vegetable in some degree.The amount of nitrogen fertilizer influences nitrate content of vegetables.Different planting patterns have significant effects on soil available nutrient contents. Soil available N,P contents for vegetable and fruit tree are obviously higher than those of seedling and grain crops. The content of N,P,K in different soil depth also varied apparently. Content of TN ,TP ,OM, NH4+-N, NO3--N, AP decrease from top soil to the deeper layer of soil in the 0-90cm soil profile, but content of AK increase slightly from top soil to deeper layer of soil.The result of nutrient balance condition of different planting patterns is listed as follows. N surplus for grain crop is 78.9 kg.ha-1.a-1, P(P2O5) and K(K2O) deficit are 38.1kg.ha-1.a-1 and 169.8kg.ha-1. a-1.N, P2O5 surplus for vegetable are 181.1 kg.ha’.a"1 and 101.7kg.ha-1.a-1, K2O deficit is 66.\kg.ha-1.a-1. N,P(P2O5),K(K2O) surplus for fruit tree are 404.7kg.ha-1.a-1,118.5kg.ha-1.a-1 and 147.0kg.ha-1.a-1. N, P(P2O5),K(K2O) for seedling are surplus slightly, but compared with fruit tree and vegetable, surplus amount of N and P(P2O5) is little.Nutrient balance conditions in a year have significant difference in different crop rotations. N surplus, P surplus or balance, K deficit exsit in crop rotations of grain crops. While the nutrientbalance condition for crop rotation of vegetable crops varied significantly.Taking fertilizer, rainfall and vegetation mulching period into account, environmental effect of different planting patterns in the valley of Huangpu river in Shanghai is preliminarily analyzed. The results shows: some crops have friendly entironmental effect,such as potato, Buxus microphylla and so on.,but other crops have bad entironmental effects, such as ZizanizLatifolia, cucumber and so on.更多还原