【作者】 岳现录；

【导师】 张维理；

【作者基本信息】 中国农业科学院 ， 植物营养学， 2009， 博士

【摘要】 近年来我国北方地区小麦-玉米轮作上农民采用一次性施肥替代分次施肥的方式日益普遍。在东北和华北地区,有畜禽养殖或易于廉价获取畜禽粪便的农户,在小麦-玉米轮作上通常会一次性施用足量畜禽粪便作为底肥,不再施用化肥,也不追肥。小麦-玉米轮作一次性基施有机肥,可充分利用畜禽粪便养分,并节约劳动力,但在这一施肥方式下,有机肥氮素的利用状况、去向及其对环境的影响尚无相关研究。为阐明华北平原的冬小麦-夏玉米轮作中一次基施有机肥的氮素利用与去向,本研究于2007年~2008年在山东陵县试验站、蓟县杨辛庄、蓟县史家屯布置了4个田间定位试验,研究一次性基施有机肥的作物产量与氮肥利用率,在陵县试验点上利用15N示踪技术,采用小区套微区的方式,通过施用15N标记有机肥,重点研究有机肥氮素的吸收、转化及在土壤剖面中的分布。主要结论如下:1、蓟县杨辛庄东试验点地力较高(产量水平较高),在冬小麦-夏玉米轮作中施氮量为300 kg N·hm-2条件下,一次性基施有机肥与分5次施化肥产量无显著区别,两季作物总产分别为18034、18101 kg·hm-2。冬小麦、夏玉米收获之后,土壤0-20cm硝态氮均无显著区别,冬小麦收获后分别为13.2、11.3 mg·kg-1,夏玉米收获后分别为7.2、7.8 mg·kg-1。陵县试验点地力较低(产量水平较低),在冬小麦-夏玉米轮作中施氮量为300 kg N·hm-2条件下,分5次施用化肥的经济产量显著高于一次性基施有机肥的经济产量,两季作物总产分别为12503、10782 kg·hm-2。冬小麦收获之后,土壤0-20cm矿质氮无显著区别,夏玉米收获之后,分次施用化肥的土壤0-20cm硝态氮为7.2 mg·kg-1,显著高于一次性基施有机肥的处理(4.6 mg·kg-1)。2、15N示踪研究显示:在冬小麦-夏玉米一个轮作周期中,对一次性基施有机肥氮用量为450 kg N·hm-2和300 kg N·hm-2的两个处理而言,产量无显著差别,分别为11087、10782kg·hm-2。高氮用量Nlost-dff(源于肥料的氮损失量)为153 kg N?hm-2,低氮处理仅为55 kg N?hm-2,差异显著;一个轮作周期过后,高氮处理的NUE(有机肥氮素利用率)为13%,显著低于低氮处理(17%),其NSoil-dff(源于肥料的土壤存留氮量)为238 kg N?hm-2,显著高于低氮处理(172 kg N?hm-2),其Nmin-dff(源于肥料的土壤矿质氮存留量)为3.7 kg N?hm-2,与低氮处理(3.1 kg N?hm-2)无显著区别。以上结果表明,高氮比低氮用量处理多施的150 kg氮素,其中约2/3损失,约1/3以有机态存留于土壤中。一次性基施有机肥氮用量为300 kg N·hm-2时,冬小麦收获后Nuptake-dff(源于肥料的作物吸氮量)、NSoil-dff(源于肥料的土壤存留氮量)、Nlost-dff、Nmin-dff分别为26、219、55、2.4 kg N?hm-2;NUE(肥料氮素利用率)、Nlost-dff-coef(肥料氮素损失率)分别为9%和18%。夏玉米收获后Nuptake-dff、NSoil-dff、Nlost-dff、Nmin-dff分别为26、172、21、3.1 kg N?hm-2;NUE、Nlost-dff-coef分别为9%和7%。一次性基施有机肥氮用量为450 kg N·hm-2时,冬小麦收获后Nuptake-dff、NSoil-dff、Nlost-dff、Nmin-dff分别为30、307、113、3.7 kg N?hm-2;NUE、Nlost-dff-coef分别为7%和25%。夏玉米收获后Nuptake-dff、NSoil-dff、Nlost-dff、Nmin-dff分别为29、238、39、3.7kg N?hm-2;NUE、Nlost-dff-coef分别为7%和9%。3、15N示踪试验结果还显示:在土壤地力较低条件下,尽管分次施用化肥(施氮量为300 kg N?hm-2)产量水平高于一次性施用有机肥(施氮量为300 kg N?hm-2),一个轮作周期后,前者0-20与0-200cm土层中的Nmin-dff(源于肥料的土壤矿质氮存留量)为7.6、8.7 kg N?hm-2,显著高于后者(2.6、3.1 kg N?hm-2);而对于分次施用化肥施氮量为450 kg N?hm-2的处理而言, 0-20与0-200cm土层中的Nmin-dff分别为11.0、15.2 kg N?hm-2,显著高于一次性施用有机肥施氮量为450 kg N?hm-2的处理(3.0、3.7 kg N?hm-2)。4、不同有机肥品种的试验结果显示:冬小麦-夏玉米轮作中施用牛粪、猪粪、鸭粪3种有机肥,施氮量为300 kg N·hm-2,一次性基施条件下,经济产量无显著区别,两季总产分别为:14961、15459、15231 kg·hm-2;两季累计氮素利用率也无显著区别,分别为18%、18%、23%。小麦收获后,施用鸭粪处理土壤0-20cm硝态氮含量(19.1 mg·kg-1)显著高于牛粪(9.8 mg·kg-1)和猪粪(13.3mg·kg-1)处理,玉米收获后,施用鸭粪处理土壤0-20cm硝态氮含量(12.8 mg·kg-1)显著高于牛粪(6.8 mg·kg-1)和猪粪(7.5mg·kg-1)处理,表明:有机肥料品种不同,肥料氮素在土壤中的矿化有显著差别。本项研究结果初步显示,在华北平原高肥力土壤条件下,小麦-玉米轮作一次性基施有机肥与多次施用等氮量化肥比较,产量基本相同;而作物收获后土壤表层硝态氮存量显著更低,农田淋溶或径流风险较低,考虑一次性基施有机肥还可节约劳动力、充分利用畜禽粪便养分,这一方式在华北平原高肥力条件下是一种值得推荐的施肥方法。更多还原

【Abstract】 In recent years, it has become increasingly widespread in the Northeast and North China that only base organic manure is applied in winter wheat-summer maize rotation without fertilizer topdressing. This fertilization measurement is usually used by farmers who raise livestock and poultry or could get cheap animal manure. In this fertilization system, worker costs for topdressing fertilization will be reduced. However, few studies were done on behavior and fate of nitrogen, especially on nitrogen efficiency and its impacts on environment by one base organic manure application in winter wheat-summer maize rotation.In order to elucidate nitrogen fate and efficiency of organic manure, four field experiments were carried out from September 2007 to October 2008, respectively in Lingxian (Shandong province), Yangxinzhuang and Shijiatun (Jixian County of Tjanjin City). These experiments were mainly used to research nitrogen use efficiency and crop yield. Besides this, experiment in Lingxian was used to research the uptake of manure nitrogen by crop, its transformation and distribution in soil environment. 15N tracer technique was adapted in this experiment, and some micro-plots and field plots were carried out too. 15N marked organic manure and chemical fertilizers were applied to these micro-plots. The main conclusions are as follows:1 ) The experimental site of east Yangxinzhuang is of higher fertility (higher yield). In the 300-N-treatments (applying 300 kg N·hm-2 nitrogen to wheat-maize rotation), there was no significant difference between crop yields of 1-OM (applying base organic manure in winter wheat-summer maize rotation without fertilizer topdressing) and 5-CF (applying chemical fertilizer for five times in winter wheat-summer maize rotation, and three times for winter wheat, twice for summer maize) fertilization measurement. Their yields (wheat plus maize) were respectively 18034 and 18101 kg·hm-2. After winter wheat and summer maize harvest, there was also no significant difference between the two kinds of fertilization measurements in 0-20cm soil NO3-N content. Their content were respectively 13.2 and 11.3 mg·kg-1 after winter wheat harvest, were respectively 7.2 and 7.8 mg·kg-1 after summer maize harvest. The experimental site of Lingxian (Shandong Province) is of lower fertility (lower yield). In the 300-N treatments, the total yield of 5- CF is significant high from that of 1-OM. Their yields (wheat plus maize) were respectively 12503 and 10782 kg·hm-2. After winter wheat harvest, the 0-20cm soil NO3-N content of 5-CF was not significantly different from that of 1-OM. After summer-maize harvest, the 0-20cm soil NO3-N content of 1-OM was 7.2 mg·kg-1, which was significant high from that of 5- CF (4.6 mg·kg-1).2)The 15N tracer studies have shown: In the periods of winter wheat– summer maize rotation, there was no significant yields difference between 450-N treatment (applying 450 kg N·hm-2 nitrogen to wheat-maize rotation) and 300-N treatment of 1-OM fertilization measurement. Their yields were respectively 11807 and 10782 kg·hm-2. The Nlost-dff (Nitrogen lost derived from fertilizer) of 450-N treatment was significantly increased to 153 kg N·hm-2, and the 300-N treatment was only of 55 kg N·hm-2. The NUE (Nitrogen use efficiency) of 450-N treatment was 13%, which was significantly lower than that of 300-N treatment (17%). The NSoil-dff (the soil nitrogen remaining derived from fertilizer) of 450-N treatment was 238 kg N·hm-2, which was significantly higher than that of 300-N treatment (172 kg N·hm-2). The Nmin-dff (the soil mineral nitrogen remaining derived from fertilizer) of 450-N treatment was 3.7 kg N·hm-2, which was no significantly difference from that of 300-N treatment (3.1 kg N·hm-2). These results have shown that 450-N treatment is application 150kg nitrogen fertilizer more than 300-N treatment, two third of them are lost, and one third of them remain in soil.In the 300-N treatment of 1-OM fertilization measurement, after winter wheat harvest, Nuptake (nitrogen absorption by the crop), NSoil-dff, Nlost-dff and Nmin-dff were respectively 26, 219, 55, 2.4 kg N·hm-2; NUE and Nlost-dff-coef (lost coefficient of Nitrogen derived from fertilizer) were respectively 9% and 18%. After summer maize harvest, Nuptake, NSoil-dff, Nlost-dff and Nmin-dff were respectively 26, 172, 21 and 3.1 kg N·hm-2; NUE and Nlost-dff-coef were respectively 9% and 7%.In the 450-N treatment of 1-OM fertilization measurement, after winter wheat harvest, Nuptake, NSoil-dff, Nlost-dff and Nmin-dff were respectively 30, 307, 113 and 3.7 kg N·hm-2; NUE and Nlost-dff-coef were respectively 7% and 25%. After summer maize harvest, Nuptake, NSoil-dff, Nlost-dff and Nmin-dff were respectively 29, 238, 39 and 3.7 kg N·hm-2; NUE and Nlost-dff-coef were respectively 7% and 9%.3)The 15N tracer studies have also shown: In the lower fertility conditions, the crop yield of 5-CF was significantly higher than that of 1-OM. After a rotation period, in 300-N treatments, soil 0-20cm Nmin-dff and 0-200cm Nmin-dff of 5-CF were respectively 7.6 and 8.7 kg N·hm-2, which were significantly higher than those of 1-OM (2.6 and 3.1 kg N·hm-2). Also, in 450-N treatments, soil 0-20cm Nmin-dff and 0-200cm Nmin-dff of 5 -CF are respectively 11.0 and 15.2 kg N·hm-2, which were significantly higher than those of 1-OM (3.0 and 3.7 kg N·hm-2) too.4)Experimental results of different varieties of organic manure showed that: In winter wheat-summer maize rotation, crop yields of 300-N had no significant difference among the treatments of applying cow dung, pig manure and duck manure. Their total (wheat plus maize) yields of different manure treatments were respectively 14961, 15459 and 15231 kg·hm-2. Their NUE (wheat plus maize) were respectively 18%, 18% and 23%, also had no significant differences. After winter wheat harvest, 0-20cm soil NO3-N content of duck manure application treatment (19.1 mg·kg-1) was significantly higher than that of cow dung application treatment (9.8 mg·kg-1) and pig manure application treatment (13.3mg·kg-1). After summer maize harvest, 0-20cm soil NO3-N content of duck manure application treatment (12.8 mg·kg-1) was significantly higher than that of cow dung application treatment 6.8 mg·kg-1) and pig manure application treatment (7.5mg·kg-1) too. These results have shown that different varieties of organic fertilizers have significant differences in nitrogen mineralization in soil.These studies are preliminary show that in the North China Plain of high fertility soil, crop yields are basically the same between 1-OM and 5- CF fertilization measurement in winter wheat– summer maize rotation. After summer maize harvest, soil 0-20cm NO3-N content is significant low, and the risk of farmland leaching or run-off is low too. Considering worker costs for topdressing fertilization will be reduced, 1-OM fertilization measurement is worthy to be recommended in the North China Plain of high fertility soil.更多还原