【作者】 肖靖；

【导师】 李莉；

【作者基本信息】 吉林农业大学 ， 环境工程， 2014， 硕士

【摘要】 为了了解草甸黑土区农田土壤氮素流失特征，通过模拟人工降雨，研究了施肥种类、施肥量、降雨强度、植被覆盖度及植被格局对氮素流失的影响。试验得出主要结论如下：(1)随着降雨强度的增大，径流量及渗漏液量均呈增加趋势。其中，在中、低雨强时，渗漏量大于径流量；而在较高雨强时，渗漏量与径流量相近或低于径流量。高雨强与中低雨强径流和渗漏液量存在显著性差异。随着植被覆盖度的增加，径流量逐渐降低，而渗漏量则增加。不同覆盖度处理径流量之间存在显著性差异，覆盖度20%～80%时渗漏液量之间存在显著性差异。(2)径流和渗漏液中总氮、硝态氮和铵态氮的流失浓度均与降雨强度成正相关，且高雨强与中低雨强径流和渗漏液中总氮、硝态氮流失浓度之间均存在显著性差异；径流中铵态氮浓度存在显著性差异，但渗漏液中铵态氮流失浓度之间无显著性差异。在中、低雨强时，渗漏流失是氮素流失的主要方式；在高雨强时，渗漏流失量与径流流失量相比，趋于接近或低于径流流失量。(3)随着施肥量的增加，径流和渗漏液中氮素的流失量均随之增加，径流和渗漏液中总氮、硝态氮流失浓度存在显著性差异，但铵态氮流失浓度仅2倍施肥与其余处理存在显著性差异。渗漏流失是各种氮素形态的主要流失方式。氮素的流失形态均是以硝态氮为主，径流中硝态氮的流失量占总氮的56.51％~64.19％；渗漏液中硝态氮的流失量占总氮的66.81%~69.70%。(4)无机肥与复合肥、有机肥处理之间，径流及渗漏液中总氮、硝态氮的流失浓度存在显著性差异。施肥种类不同，氮素的流失规律不同。径流中和渗漏液中无机肥处理氮素的流失量均最高。其中，径流中总氮、硝态氮流失规律为无机肥＞复合肥＞有机肥，铵态氮的流失规律为复合肥＞有机肥＞无机肥；渗漏液中总氮、硝态氮和溶解性氮流失规律均为无机肥＞复合肥＞有机肥，而铵态氮的流失规律与总氮不同，其流失浓度的大小为：复合肥＞有机肥＞无机肥。(5)施肥后降雨时间不同，氮素流失量也不同。径流中，施肥后1～7d，总氮的流失浓度达到总流失浓度的50%以上；渗漏液中总氮的流失量均与降雨时间呈负相关，其中渗漏液中硝态氮和铵态氮，均在第7d时流失浓度达到最大。(6)无论何种覆盖度，渗漏液中总氮、硝态氮和铵态氮累积流失量均远远大于径流中氮素的累积流失量。覆盖度40％时，总氮流失总量（径流累积流失量+渗漏累积流失量）为1528.9mg/m2，分别比覆盖度0％、20％、80％低10.3％、2.8％、26.8％。(7)坡下格局与坡上及坡中格局总氮、硝态氮和铵态氮存在显著性差异。无论何种植被格局，渗漏液中总氮流失量远远超过径流中总氮流失量。坡下格局对抑制总氮的流失效果最好，坡下格局比坡中及坡上格局总氮流失量分别降低15.4％和5.1％。硝态氮和铵态氮流失总量与总氮一致，均为坡中格局＞坡上格局＞坡下格局。更多还原

【Abstract】 The tests of different kinds of fertilizer, the amount of fertilizer, rainfall intensity,vegetation coverage and vegetation pattern to nitrogen leaching are conducted undersimulated rainfall in order to find out the characteristics of meadow black soil nitrogen loss.The main conclusion after testing as follows:(1) With the increase of rainfall intensity, runoff and leakage of the fluid volume areincreased. Among them, in the middle and low rainfall intensity, the leakage is greater thanthe amount of runoff; But in the higher rainfall intensity, similar or lower than that ofrunoff and runoff amount of seepage.There was a significant difference between highrainfall intensity with low rainfall intensity in runoff and leakage.With the increase ofvegetation coverage, runoff decreases gradually, while seepage quantity increase. Therewas a significant difference between the different coverage processing in runoff when thereare significant differences between20%~80%coverage in leakage.(2) The concentration of loss of Total nitrogen, Dissolved nitrate nitrogen andDissolved ammonium nitrogen in leachate and runoff are positively related to the intensityof rainfall. There were significant differences between high rainfall intensity and lowrainfall intensity of Total nitrogen, Dissolved nitrate nitrogen loss concentration in runoffand leachate. Ammonium nitrogen in the runoff exists significant difference, but the loss ofammonium nitrogen in the leachate there was no significant difference.Ammoniumnitrogen in the runoff concentration exists significant difference, but the loss of ammoniumnitrogen concentration in the leachate there was no significant difference between In themiddle and low rainfall intensity, leakage loss is the main way of nitrogen loss; When highrainfall intensity, leakage loss compared with runoff erosion, tend to be close to or evenlower than that of runoff erosion.(3) With the increase of fertilizer rate, runoff and leakage of liquid nitrogen loss areincreased.There was a significant difference between Total nitrogen, Dissolved nitratenitrogen in runoff and leakage,the concentration of Dissolved ammonium nitrogen onlydouble fertilization exist.The seepage erosion is a major loss of various nitrogen forms. Theform of nitrogen loss are predominantly within Dissolved nitrate nitrogen, Dissolved nitrate nitrogen loss in runoff accounted for56.51%~64.19%of Total nitrogen; Dissolved nitratenitrogen loss in leachate accounts for66.81%~69.70%of Total nitrogen.(4) The concentration of Total nitrogen, Dissolved nitrate nitrogen loss in runoff andleakage exists significant difference between inorganic fertilizer, compound fertilizer andorganic fertilizer.Different kinds of fertilizing of different laws of nitrogen losses. Thenitrogen loss of inorganic fertilizer was highest in runoffand leskage. The rule of Totalnitrogen, Dissolved nitrate nitrogen loss in runoff is inorganic fertilizer＞compoundfertilizer＞organic fertilizer in the circumstances of equal nitrogen fertilization. The rule ofDissolved ammonium nitrogen loss is compound fertilizer＞organic fertilizer＞inorganicfertilizer. The rules of Total nitrogen, Dissolved nitrate nitrogen and Total dissolvednitrogen loss are agreement which is that inorganic fertilizer＞compound fertilizer＞organic fertilizer. Dissolved ammonium nitrogen loss concentration which is different fromTotal nitrogen is that compound fertilizer＞organic fertilizer＞inorganic fertilizer.(5) Rainfall interval is different, after fertilization of nitrogen loss is also different.After fertilization1~7d, the of concentrations of Total nitrogen loss reach more than50%of the concentration of total loss in runoff; The loss of Total nitrogen in leakage showed anegative correlation with rain fertilization interval, within Dissolved nitrate nitrogen andDissolved ammonium nitrogen loss in leachate which have reached the maximum at7d.(6) In all vegetation coverage,the loss of Total nitrogen、Dissolved nitrate nitrogen andDissolved ammonium nitrogen in leakage was all higher than in runoff. Coverage is40%,the total loss of Total nitrogen (accumulated runoff loss and leakage of cumulative loss) of1528.9mg/m2, lower than the coverage of0%,20%,80%respectively10.3%,2.8%,26.8%.(7) There was a significant difference between Total nitrogen, Dissolved nitratenitrogen and Dissolved ammonium nitrogen of under the slope pattern、in the slope and upthe slope pattern.Loss of Total nitrogen in leakage was all higher than in runoff no matterhow the vegetation pattern was. The effect of inhibit the loss of Total nitrogen is the bestwhen under the slope pattern. Under the slope pattern of15.4%and5.1%than in the slopepattern and on the slope pattern. Loss of Dissolved nitrate nitrogen and Dissolvedammonium nitrogen were agreement with Total nitrogen.更多还原