Improving water use efficiency in rice irrigation through wet-seeding

Since the early-1960's, when modern rice production technologies became available, more than 90% of the total irrigation water developed in south and southeast Asia is used for rice culture. But currently rice culture is highly inefficient in water use. As fresh water availability for agriculuture is becoming increasingly scarce, greater efficiency of water use in rice culture is deemed essential. Past experience indicates that effective implementation of water-efficient irrigation methods in rice farms within public sector irrigation systems is restricted by the difficulty of controlling water deliveries and distribution, and establishing a water charge system based on the actual amount of water used by farmers. Clearly, a rice production method that is inherently less water-requiring, or more water-efficient, would have an advantage over the traditional method in this respect. Recent studies conducted in the Philippines indicate that wet-seeded rice culture is superior to the traditional transplanted rice culture in terms of water efficiency. Other advantages of wet-seeded rice culture include its greater drought tolerance, less labor requirement for crop establishment and weed control, and higher returns from rice farming. This paper presents a comparative study of wet-seeded and transplanted rice cultures focusing on these aspects.     

水稻节水灌溉制度的研究

水稻节水灌溉的研究,各地均在开展。本文针对南水北调东线第一期工程规划范围内1400万亩水稻灌溉用水量大,而水资源短缺,远途调来的水更为珍贵的状况,从水稻耗水量,灌溉方式等方面较系统地研究了水稻节水灌溉问题,提出了推广湿灌的科学依据,以及这一措施所能产生的经济效益。     

湖北省中稻灌溉定额修订研究

湖北省现行灌溉用水定额标准颁布于2003年,已难以适应当前及今后的水资源管理需求。【目的】为更全面真实地反映湖北省中稻现状灌溉用水水平。【方法】本文分析了湖北省各分区中稻作物系数、稻田渗漏量、泡田期水面蒸发量、饱和需水量、生育期、水层控制标准等灌溉定额计算参数。【结果】基于中稻灌溉定额影响因素分析,提出了人工、机械2种耕作方式与浅灌适蓄、间歇灌溉2种灌溉模式组合下不同分区不同频率的中稻灌溉定额。定额修订成果表明,先进的灌溉模式和耕作方式都能够有效降低中稻灌溉定额,促进农业节水。【结论】目前,湖北省一般适用机械耕作、浅灌适蓄条件下的中稻灌溉定额,对于水源和灌溉工程设施条件较好的地区建议采用机械耕作、间歇灌溉条件下的灌溉定额。     

基于多目标模糊规划的灌区多水源优化配置

以黑龙江省和平灌区为例,构建基于多目标模糊规划的灌区多水源优化配置模型,该模型能够在提高农业灌溉用水净效益的同时有效减少农业灌溉水量,促进和平灌区多水源高效配置。采用具有非线性隶属度函数的模糊多目标规划求解模型,得到不同流量不同水源下的最优配水方案。结果表明:不同流量水平下水稻不同生育阶段均存在缺水现象,低流量下需从柳河水库引入外调水才能保证水稻的最小需水量。为保证灌区整体效益,按照引水工程、提水工程、井灌工程的先后顺序进行配水,并得到多目标配水模型在不同情景下的运行稳定情况。该模型可以高效地进行灌区多水源在作物各生育阶段的优化配置。     

水稻控制灌溉技术在我国东北三省的应用分析

控制灌溉技术在水稻灌溉理论上是一个突破,控制灌溉实现了既节水又增产,是水稻生产的先进技术之一。通过开展我国东北三省水稻控制灌溉技术应用情况调查,综述了目前东北三省水稻种植区节水灌溉技术现状,分析了不同灌溉方式对粮食产量的影响。同时,在黑龙江选择试验区进行了节水灌溉技术的试验分析,结果表明,水稻控制灌溉技术在我国东北可望...     

不同灌溉量对土壤理化性质及水稻生长发育的影响

水分是水稻正常生长发育的关键因素之一,【目的】研究不同灌溉量对黄河滩重构土体理化性质及水稻生长发育的影响。【方法】2017年以"吉宏6号"为试验材料,设计4个灌溉量处理,即:高水W1(120%ET0)、适水W2(100%ET0)、节水W3(80%ET0),低水W4处理(60%ET0),分析了不同灌溉量对土壤理化性质,水稻生长发育、产量的影响。【结果】土壤理化性质,水稻生长发育及产量受不同灌溉量影响显著,随着灌溉量的增加,水稻收获后土壤pH值、电导率以及土壤养分残留量也逐渐减降低。当灌溉量降低到80%ET0,水稻单株株高、分蘖数及产量都有明显降低,水稻生长发育受到一定影响,另外从高水W1处理(120%ET0)到低水W4处理(60%ET0)的水稻产量看出,随着灌溉量的增大,水稻产量呈现出先升高后降低的趋势。【结论】韩城下峪口土地整治项目区水稻种植适宜参考试验W2处理的灌溉量。     

赣抚平原灌区双季稻优化灌溉方式研究

采用田间对比试验的方法,测定双季早、晚稻的耗水量,研究2012年赣抚平原灌区不同灌溉方式下双季早、晚稻的水量与产量之间的相互关系。结果表明,间歇灌溉方式下早、晚稻本田期的腾发量、地下渗漏量、作物系数均低于淹水灌溉;与淹水灌溉方式相比,早、晚稻间歇灌溉处理本田期的耗水量分别减少4.35%和4.61%,作物系数（Kc）分别减少4.00%和3.45%,水分利用效率分别提高1.37%和2.96%,产量分别增加3.30%和1.40%。     

基于生物炭添加的控制灌排对水稻抗倒伏能力及产量的影响

为探究生物炭施加后控制灌排对水稻生长发育及产量的影响,于2016年在涟水县水利试验站开展了测坑试验,共设置轻旱控排W-1、重旱控排W-2两种控制灌排模式及无生物炭施加B-0、生物炭施加B-1两种生物炭施加水平,对水稻生长指标、水稻抗倒伏性能、产量指标进行了监测与分析。结果表明生物炭添加及控制灌排W-2条件下,水稻株高均得到显著提高。施加生物炭可以缩短水稻节间长度、增大茎壁厚度及节间外径,显著提高水稻的抗倒伏能力,但在控制灌排W-2条件下,水稻的倒伏指数升高,累积破坏能量下降,水稻抗倒伏能力呈现下降的趋势。控制灌排与生物炭添加均对水稻穗长和空秕率有显著影响,其中控制灌排的影响更为明显,生物炭添加和控制灌排W-2单因素作用均显著提高了水稻产量,但两者交互作用却对产量影响不显著,相关水炭耦合效果还需进一步试验研究。     

漳河灌区实行费改税对水稻用水的

结合国际合作项目对漳河灌区的主要农业作物－水稻在费改税制度实行前后灌溉成本和产量的变化情况进行调查，并对调查结果进行分析。结果表明：实施费改税制度的实行可以减轻农民的负担，但是增加了灌区水库供水和水管理的难度，增加了水稻生产灌溉成本。由于没有采取相应的措施，造成了水稻减产。因此，有必要对费改税前后水稻生产的变化情况做进一步的研究，减少不利影响，使得农民既能减少税费开支，又能增加水稻产量。     

Agronomic and socio-economic analysis of water management techniques for dry season cultivation of common bean in Malawi

A study was carried out in Malawi to compare agronomic and socio-economic aspects of different water management practices for two advanced bean lines. Four irrigation technologies and one control were studied in Chingale Area Development Program in Zomba District in southern Malawi. The technologies encompassed motorized pumps (MP), treadle pumps (TP), water cans, gravity-fed surface irrigation (GR) and a non-irrigated practice that used residual moisture. The study found that technologies that used <2 labour hours m^?3 were appropriate for such small-scale irrigation systems. The aggregated bean production labour cost and labourday thresholds were $893 ha^?1 and 2,978 LD ha^?1, respectively. An irrigation supply in the range of 7,000–10,000 m³ ha^?1 for the TP, MP and GR would be adequate. Assuming 20 irrigations season^?1, 400–600 m³ irrigation^?1 would be adequate, supplying 40–60 mm every 5–7 days. The study found that poor small-scale farmers in Malawi, particularly those using MPs, need fuel subsidies in order to offset operational costs. Basing on the findings in the study, we recommend further research on several bean lines in different agro-ecologies of Malawi using technologies that showed high yields, low labour efficiency and high water use productivity.     

江西省水稻蓄雨间歇灌溉模式初探

【目的】探索水稻蓄雨间歇灌溉模式节水减排效益。【方法】以鄱阳湖区双季早晚稻为试验材料,采用大田和测坑试验,研究了水稻蓄雨间歇灌溉模式对灌溉定额、排水定额、降雨有效利用率、产量、稻田水分生产率,以及氮、磷排放量的影响,并与间歇灌溉和常规淹水灌溉试验进行了分析比较。【结果】与淹水灌溉、间歇灌溉相比,蓄雨间歇灌溉灌排水量、灌排次数明显减少。双季早晚稻年平均灌水量分别减少975m^3/hm^2和1251m^3/hm^2,年平均灌水次数分别减少8次和7.5次;年平均排水量分别减少729 m^3/hm^2和893 m^3/hm^2,年平均排水次数分别减少5.8次和3.1次;蓄雨间歇灌溉降雨有效利用率明显提高。早稻降雨利用率分别提高12.40%和9.14%,晚稻分别提高6.84%和6.42%;蓄雨间歇灌溉模式下,双季早晚稻总氮排放量年平均减排7.64 kg/hm^2和3.12 kg/hm^2,减排幅度34.93%和14.26%;双季早晚稻总磷排放量0.180kg/hm^2和0.095kg/hm^2,减排幅度37.25%和70.59%。【结论】蓄雨间歇灌溉模式具有明显的节水、减排和提高降雨有效利用率的效果,在我国南方多雨地区具有较强的推广应用空间。     

施加生物炭对节水灌溉水稻生长特征及产量影响

为揭示施加生物炭对节水灌溉水稻生长特征及产量的影响,试验设计常规灌溉和控制灌溉两种灌溉方式,采用盆栽试验,分析了施加生物炭条件下节水灌溉水稻的茎蘖、株高、叶面积指数(LAI)、叶绿素(SPAD)、产量、灌水量以及灌溉水分生产率的变化规律。结果表明:与常规灌溉相比,控制灌溉轻微抑制了水稻地上部分的生长,保证了水稻稳产,灌水量平均减少34.91%,灌溉水分生产率平均提高了0.69kg/m~3。施加生物炭处理增加了水稻茎蘖数、株高以及LAI,提高了水稻的有效分蘖率,使水稻对氮素吸收相对平稳,SPAD值变化波动小,水稻产量平均提高947kg/hm~2,灌溉水分生产率平均提高0.16kg/m~3。控制灌溉与生物炭联合应用水稻灌溉水分生产率最高,为2.12kg/m~3。     

设施栽培中渗灌技术研究现状与发展趋势

归纳总结了渗灌对设施栽培作物生长环境及产量的影响、设施栽培渗灌系统的主要设计参数及灌水指标,分析了目前研究中存在的问题。提出了今后应将设施栽培条件下土壤、作物、室内、外空间环境作为一个连续体建议,研究不同渗灌条件及不同土壤类型中连续体内的传热、传质特性;研究渗灌调控土壤水分的技术参数以及各种设施栽培作物的渗灌灌水指标及灌水制度;研究湿润地区设施栽培渗灌调控土壤水分的技术等。     

拔节孕穗和抽穗开花期控制灌溉对水稻生长的影响

在水稻拔节孕穗和抽穗开花期,分别以土壤饱和含水率的70%、80%和90%作为灌溉下限进行控制灌溉。结果表明,与常规灌溉相比,拔节孕穗期水分控制条件下水稻生长受到抑制,单穴有效穗数和千粒质量变化较小,每穗粒数和每穗实粒数显著减少,产量也有减小趋势,但差异不显著;抽穗开花期控制灌溉对水稻生长和产量影响相对较小,均未达到显著水平;拔节孕穗期控制灌溉较抽穗开花期节水效应明显,但抽穗开花期控制灌溉有利于获得更高的水分生产效率,因此,制定水稻控灌灌溉制度时,拔节孕穗期轻控,抽穗开花期适当增大水分控制下限有利于水稻节水增产。     

水氮调控对水稻氮素吸收与利用的影响

合理的水肥运筹对提高水稻氮素利用效率和水稻产量有很大影响。根据大田试验资料,分析了不同水分管理和氮肥管理对水稻氮素吸收利用及在植株体内分布的影响。结果表明:控制灌溉模式显著改善了水稻对氮素的吸收,促进氮素在籽粒中的积累;实地氮肥管理(SSNM)模式有效控制了生育前期营养器官对氮素的吸收,有效促进了水稻秸秆中累积的氮素参与再分配与再利用;控灌与SSNM联合调控有效地控制无效分蘖,显著降低秸秆氮素含量,提高了水稻营养器官氮素的转运量。控灌和SSNM处理节省了水肥的投入,提高了水肥利用效率,为南方灌区实现合理的水肥管理提供了依据。     

水氮互作对水稻产量及品质的影响

为了探索水稻优质高效水氮供应模式,以郑稻18和信粳18为材料,设置常规灌溉(CI)、湿润灌溉(SI)和控制灌溉(KI)3种灌溉方式;中肥(MN,225kg/hm2)和高肥(HN,300kg/hm2)2种施氮水平,以不施肥(CK)为对照,通过大田试验重点研究了水氮互作对水稻产量及品质的影响。结果表明:与CK相比,施氮显著增加了产量,但随着施氮量的增加,不同灌溉方式下2品种对氮肥的响应有所差异。稻米品质各指标的氮肥效应大于灌溉水平的影响,水氮互作对郑稻18米质的影响大于信粳18。MN较CK和HN更有利于提高稻米品质,在KI和SI下,稻米加工、外观和营养品质略优于CI。因此,在中等施肥量(MN)条件下,采用控制灌溉(KI)模式进行水、肥管理,可在一定程度上使2品种的产量和品质得到协调。     

微纳米气泡增氧灌溉对双季稻需水特性及产量的影响

为探究微纳米气泡增氧灌溉技术对水稻节水增产的综合影响,以陆两优996和天优华占为双季早、晚稻试验材料,研究了不同施氮水平下微纳米气泡增氧灌溉对双季稻需水特性、产量及产量构成因素的影响。结果表明,微纳米气泡增氧灌溉处理的灌水量、排水量和耗水量均低于常规水灌溉处理,早、晚稻水分利用效率(耗水量)分别提高7.78%和8.37%,降雨利用效率分别提高6.03%和24.58%,产量分别提高4.05%和3.35%。同时,微纳米气泡增氧灌溉具有良好的节肥效果。     

Exploring options for water savings in lowland rice using a modelling approach

Water-saving irrigation regimes are needed to deal with a reduced availability of water for rice production. Two important water-saving technologies at field scale are alternately submerged–nonsubmerged (SNS) and flush irrigated (FI) rice. SNS allows dry periods between submerged soil conditions, whereas FI resembles the irrigation regime of an upland crop. The effects of these regimes on the water balance and water savings were compared with continuously submerged (CS) and rainfed (RF) regimes.The crop growth model ORYZA2000 was used to calculate seasonal water balances of CS, SNS, FI, and RF regimes for two locations: Tuanlin in Hubei province in China from 1999 to 2002 during summer seasons and Los Baños in the Philippines in 2002–2003 during dry seasons. The model was first parameterized for site-specific soil conditions and cultivar traits and then evaluated using a combination of statistical and visual comparisons of observed and simulated variables. ORYZA2000 accurately simulated the crop variables leaf area index, biomass, and yield, and the soil water balance variables field water level and soil water tension in the root zone.Next, a scenario study was done to analyse the effect of water regime, soil permeability, and groundwater table depth on irrigation requirement and associated rice yield. For this study historical weather data for both sites were used.Within seasons, the amount of irrigation water application was higher for CS than for any of the water-saving regimes. It was found that groundwater table depth strongly affected the water-yield relationship for the water-saving regimes. Rainfed rice did not lead to significant yield reductions at Tuanlin as long as the groundwater table depth was less than 20 cm. Simulations at Los Baños with a more drought tolerant cultivar showed that FI resulted in higher yields than RF thereby requiring only 420 mm of irrigation.The soil type determined the irrigation water requirement in CS and SNS regimes. A more permeable soil requires around 2000 mm of irrigation water whereas less permeable, heavy soil types require less than half of this amount. We conclude that water savings can be considerable when water regimes are adapted to soil characteristics and rainfall dynamics. To further optimize water-saving regimes in lowland rice, groundwater table dynamics and soil permeability should be taken into account.     

江苏省水稻节水灌溉技术推广模式

针对江苏省稻作区水资源、土壤、气候的特点 ,选择浅湿灌溉、浅湿调控灌溉、控制灌溉、水稻旱作灌溉等 4种技术因地制宜进行推广。在灌溉过程中 ,建立和完善了一整套的组织措施和技术措施 ,形成了江苏省水稻节水灌溉技术推广模式 ,取得了显著的效果 ,丰富了水稻节水灌溉技术推广的内容