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核心期刊论文目录 |
江南丘陵区双季稻田水分管理研究 |
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| 出 版 社：中科院硕士学位论文 |
| 发表时间：2007.07 |
| 台 站：
桃源农业生态试验站
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| 作 者：唐彬 |
| 点 击 率：6669 |
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| 关 键 字：水分管理；水稻；水分利用效率；耗水量；土壤生态环境 |
| 摘 要：比较研究江南丘陵双季稻区不同水分管理对稻田耗水特征、作物生产力以及土壤生态环境的影响，是优化不同水源和灌溉条件下的水分管理模式，建立相应管理技术的前提。本文依托9年水分管理长期定位试验，系统比较了不同水分管理下的土壤生态环境、稻田耗水特征以及作物生产力和水分利用效率，探讨了不同水源和灌溉条件下早晚稻生产适宜的水分管理模式。结论如下：
（1）水分管理对表层（0-20cm）土壤有机质和全氮含量以及物理性状产生了明显影响。淹灌表层（0-20cm）土壤有机质和全氮含量高，容重小，总孔隙度和毛管孔隙度多，持水力强，田间持水量最高，有利于保蓄水分和养分；同时昼泥温低，变化平缓。而天灌表层（0-20cm）土壤有机质和全氮含量低，容重大，总孔隙度和毛管孔隙度少，持水力弱，田间持水量最低，不利于保蓄水分和养分；同时昼泥温高，变化快。湿灌与配灌表层（0-20cm）土壤有机质和全氮含量以及物理性状比较接近，保水保肥性和昼泥温变化介于中间。
（2）早稻生产淹灌耗水量和日平均耗水速率最低，灌水量多于湿灌和天灌，明显少于配灌，农业用水和灌溉水分利用效率与湿灌差不多，低于天灌，高于配灌。可通过提高水管理技术水平，减少排水次数和排水量，充分利用雨水来减少灌溉量，进一步提高各处理（天灌除外）的灌溉水分利用效率。淹灌较深水层有利于缓解天气骤变对水稻生长的影响，其高峰期叶面积、光合速率、干物质积累总量以及产量较其他处理均略有增加，多年平均产量比配灌、天灌和湿灌高148、317和390 kg•hm-2。对于降水丰富的早稻生产，最适宜选用淹灌模式。不过对于水源条件差和灌溉无保障的稻田，可采用天灌模式。
（3）晚稻生产耗水量、日平均耗水速率以及灌水量均以配灌最高，天灌最低，淹灌略高于湿灌。天灌、淹灌和湿灌的叶片光合速率与高峰值叶面积较配灌明显降低，不过地上部干物质量和产量除天灌较配灌明显降低外，淹灌和湿灌较配灌均无明显降低，其中湿灌降低更少。而农业用水和灌溉水分利用效率天灌、淹灌和湿灌较配灌明显增高。对于干旱严重的晚稻生产，最适宜选用湿灌模式。与配灌相比，湿灌能节约灌溉用水量32.9％。不过晚稻生产还应考虑区域具体的水源和灌溉条件，在水源充足和灌溉条件非常好的区域，为了提高产量，宜选用配灌模式。在水源条件差和灌溉无保障的稻田，不能依赖雨养进行晚稻生产。
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| 关 键 字(英文)：water management regimes, rice, water use efficency, water consumption, soil eco-environment |
| 摘 要(英文)：A long-term water management field experiment had been carried out for nine years to study the water requirement of paddy fields, rice productivity, water use efficiency (WUE) and the variable of soil eco-environment under different water management regimes, to find out the most suitable water management method under different water resources and irrigation conditions. The results showed:
(1) Different water managements had important effects on soil organic matter content, total nitrogen content and physical properties between 0-20cm layer. Under continuous flooding irrigation (CSF), surface layer soil of 0-20cm had the highest organic matter and total nitrogen content，the lightest bulk density，the most total porosity and capillary porosity and the strongest retention ability，which were favourable to preserve water and nutrients. Meanwhile, the soil temperature in the daytime was low and changes gently in CFS. Under rain maintenance irrigation (RMI), surface layer soil of 0-20cm had the lowest organic matter and total nitrogen content，the most heavy bulk density，the fewest total porosity and capillary porosity, and the weakest retention ability，which went against keeping water and nutrients. Meanwhile soil temperature in the daytime was high and changes quickly in RMI. 0-20cm soil under moisture condition irrigation (MSC) and normal irrigation (NLI) field had resemble organic matter content, total nitrogen content and physical properties, and their water and nutrients storage abilities and soil daily temperature variation intervene between CSF and RMI.
(2) In early rice, CSF had the least total water consumption and average daily water consumption rate. The irrigation water in CSF was more than that in MSC and RMI , but obviously less than that in NLI. Irrigation water use efficiency (IWUE) and agricultural water use efficiency (AWUE) of CSF was almost the same as that of MSC, but obviously less than that of rain maintenance irrigation (RMI) and more than that of NLI. IWUE in CSF, NLI and MSC could further be increased by improving water management technology, such as reducing drainage times and quantity, making full use of rainwater and.cutting down irrigation water. The deep water in CFS was in favor of mitigating effects of weather sharp change on rice growth. The peak leaf area, leaf photosynthetic rate, accumulation of dry matter and grain yield under CFS were slightly higher than those in other water regimes. The average grain yield in CFS was increased by 148, 317 and 390
kg•hm-2 than those in NLI, RMI and MSC, respectively. CFS was the most suitable irrigation method in early rice with rich rain. But for the fields with bad water resources and irrigation condition, RMI was selectable for early rice.
(3) In later rice, the total water consumption, average daily water consumption rate and irrigation water were NLI > CFS > MSC > RMI. The leaf photosynthetic rate and the peak leaf area in RMI, CFS and MSC were obviously lower than that in NLI, but the accumulation of above-ground dry matter and grain yield in CFS and MSC except for that in RMI were not obviously lower than that in NLI, especially that in MSC. AWUE and IWUE in RMI, CFS and MSC were obviously higher than that in NLI. MSC was the most suitable water management method in later rice with serious drought. IWUE in MSC was reduce by 32.9% than that in NLI. But in later rice, the actual water resources and irrigation conditions must be considered. For the regions with sufficient water resources and better irrigation condition, NLI was the most suitable irrigation regime to improve grain yield. For the regions with bad water resources and irrigation condition, the later rice only with rainfed can not be planted.
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