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SCI论文目录 |
有机无机肥配施对红壤稻田土壤肥力及稻谷产量的影响 |
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| 出 版 社：中科院硕士学位论文 |
| 发表时间：2005.07 |
| 台 站：
桃源农业生态试验站
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| 作 者：陈安磊 |
| 点 击 率：15611 |
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| 关 键 字：稻田,土壤肥力,稻谷产量,化肥,有机养分循环利用 |
| 摘 要：研究化肥施用及其配合有机肥施用对稻田土壤肥力及其生产力影响，是合理利用农业废弃物、制定合理施肥模式的前提。本文依托中国科学院桃源农业生态实验站长期定位试验—不同施肥制度对红壤稻田系统生产力及其土壤环境的影响，通过NPK肥逐步引入稻田生态系统及其配合有机肥施用下土壤理化性质、生物学特性及其作物产量变化特征，揭示了红壤稻田土壤养分变化特征，土壤供应能力及其对稻谷产量的影响。主要结果如下：
14 a不施肥土壤容重降低了12.0％，施用化肥土壤容重平均降低了12.8％，有机无机肥配合施用能显著降低土壤的容重（平均降低了25.6%）。可见稻田土壤不会出现板结现象。
12a不施肥（CK），土壤有机碳含量上升了1.6 g/kg （提高幅度平均为11.7 ％），施用化肥土壤有机碳平均提高了2.9 g/kg（提高幅度平均为19.0％），有机肥的施用能明显提高土壤有机碳含量，提高幅度平均为28.5％。有机碳归还量大和淹水状态是稻田土壤有机碳快速积累的主要原因。
长期不施肥土壤N、P库分别降低了6.4％和25.0％。施用化肥对土壤N、P库和速效养分没有显著影响，化肥基础上有机养分循环利用，土壤N库提高明显，在施用P肥后土壤磷库才有明显提高。有机养分循环利用配合NP或NPK肥的施用，能提高土壤速效养分在作物关键生育期的含量。
长期不施肥稻田土壤微生物生物量C、N、P分别为811.0~1524.7 mg/kg土、81.4~158.1mg/kg、19.2~41.8 mg/kg，与以往旱地的研究结果相比，稻田土壤能维持较高的微生物生物量。施用化肥对对土壤MB-C、MB-N、MB-P没有显著的影响（P<0.05）；而施用有机肥能显著提高土壤MB-C，化肥和有机肥配合施用大幅度提高MB-N和MB-P，其中NP肥或NPK肥配合有机肥施用提高幅度达到显著水平（p<0.05）。土壤MB-C与年际有机碳的投入量有极显著的正相关关系（r＝0.959**），另外土壤微生物生物量碳、氮、磷分别与土壤有机碳、土壤全氮、速效磷有显著的正相关关系（p<0.01）。
施用有机肥可大幅度提高微生物对N素和P素的固持量，化肥配施有机肥与仅施用化肥相比，平均每公顷稻田土壤土壤微生物多固定83.3 kg的N素，施用有机肥或与氮肥配合施用，每公顷土壤微生物平均多固定11.5 kg的 P素，磷肥配合有机肥与仅施用磷肥相比每公顷土壤微生物平均多固定35.2 kg的P素。可见养分循环利用对调节土壤氮素供应、提高氮肥利用率和减少氮肥对环境的污染和活化土壤磷有重要的意义。另外施用化肥对土壤微生物生物量占土壤全氮、磷、钾比例影响不大（分别为5.7％、5.4％和4.1％），化肥配合有机肥施用，提高了微生物生物量碳、氮、磷所占的比例（分别为7.2％、6.1％和4.6％）。
稻田长期养分循环利用，水稻的生长状况要优于只施化肥或不施化肥的生长状况，随着NPK养分和有机养分循环利用配合程度的提高，水稻的分蘖数和干物重逐渐提高。长期不施用P肥，即使系统内有机养分循环利用，P素的缺乏也是作物生长发育的主要限制因素；红壤稻田长期不施用K肥，土壤缺K是作物生长的限制因素。相关性分析也可以看出，作物吸收 (N, P和 K)养分和地上干物重与土壤养分(N, P和 K)有显著的正相关关系。
在养分供应充足的条件下，有机肥投入获得的产量”报酬”较低，随着NPK肥配合程度的提高，有机肥的增产效益逐渐降低（分别为55.4％、44.2％、18.2％和9.6％）。长期偏施化肥使得养分平衡失调，导致土壤某些养分供应出现严重不足或降低是长期施用N肥或NP肥增产效应逐渐降低的原因，也是有机肥配合N肥或NP肥施用化肥增产效应降低的原因。
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| 关 键 字(英文)：paddy soil, soil fertility, grain yield, fertilizer, organic nutrient recycling |
| 摘 要(英文)：Researches on the effects of fertilization systems and nutrient recycling are useful for understanding changes in soil fertility and grain yield, and also helpful to making reasonably utilizing of organic matter and fertilization strategies. The experiment based on the long-term experiment—the effects of different fertilization systems on soil productivity and environments in rice cropping system of red soil at Taoyuan Station of South China, aimed to study the mechanisms of soil fertility in paddy soil, such as the changes in soil bulk density, soil organic matter, soil N、P、K，soil N、P、K supplying capacity，microbial biomass, grain yield under different fertilization systems. The main results were as follows:
Data demonstrated that soil bulk density in paddy soil with no fertilizer or application of inorganic fertilizers decreased by 12.0％ and 12.8%(in average) over past 14 years respectively, while with applications of organic fertilizers have a significant effect on the soil bulk density, which decreased 25.6%.
Until 2002, soil organic matter in paddy soil with no fertilizers or application of inorganic fertilizers lightly increased by 1.6g/kg soil and 2.9g/kg soil (in average) respectively. As for total N、P and available nutrients have a slightly increased or decreased under no fertilizers or with application of inorganic fertilizers. Organic fertilizer significantly increased the soil organic matter by 3.9 g/kg soil in average, and also significantly increased soil total N，P，NH4-N ,Olsen-p and available K. Without chemical P fertilizer, soil Olsen-p was less than 10 mg/kg soil, while application of organic fertilizer has little effect on the Olsen-p and total P.
Microbial biomass C、N and P（811.0~1524.7、81.4~158.1、19.2~41.8 mg/kg soil,respectively）in paddy soil were generally larger than those in upland arable soil, as indicated in previous publications, which suggests that paddy soil has relatively strong ability to maintain the microbial biomass. Microbial biomass C、N and P in soils was not significantly affected by inorganic fertilizers, but obviously increased by the application of organic fertilizers. Microbial biomass C、N and P in the soils accounted, in average, for 5.7％、5.4％ and 4.1％ of total organic C、N and P，these percentages were little affected by the application of inorganic fertilizers, while increased by application of organic fertilizers( 7.2％、6.1％ and 4.6％ respectivly), Moreover, microbial biomass C、N and P had a significant relationship(p<0.01) with soil total C and N, and Olsen-P respectively, and also enhanced the fixation of microbial to N and P nutrients with organic fertilizer.
Plant growth showed better with application of organic fertilizer than with no fertilizer or application of chemical fertilizer. There were significant correlations between biomass and measured soil parameter, between nutrients of plant with the measured soil parameter.
The recycling use of Organic nutrients increased grain yield, which will be reduced with increasing the combinative degree of fertilizer N, P and K application (55.4％、44.2％、18.2％ and 9.6％,respectively), and also reduced with the year under long-term application of N fertilizer or combined with N fertilizer and organic nutrient recycling.
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