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1.
以畦灌玉米为研究对象,利用彭曼公式计算玉米理论需水量,并结合作物根层贮水量、生理指标及产量等确定宁夏中部干旱带玉米畦灌灌溉制度。结果表明,研究区年参考作物腾发量为1 112mm,玉米生育期需水量为596mm,理论灌溉水量为4 132m3/hm2;30~60cm是玉米根区主要贮水层;灌水后各水分处理光合有效辐射均下降,12:00、14:00降幅分别为13.7%~24.6%、1.8%~5.9%。玉米抽雄期光合速率及蒸腾速率日变化趋势一致,均呈单峰曲线,并于10:00—14:00出现峰值。灌溉定额为3 900m3/hm2时,产量最高,为14 860.5kg/hm2;灌溉定额为3 300m3/hm2时,水分利用效率最高,为4.13kg/m3。宁夏中部干旱带畦灌玉米最优灌溉制度为:全生育期灌水4次,灌水定额为975m3/hm2,灌溉定额3 900m3/hm2。  相似文献   

2.
宁夏中部干旱带覆膜沟灌玉米灌溉制度研究   总被引:2,自引:0,他引:2  
在宁夏中部干旱带设立试验区,以覆膜沟灌玉米为研究对象,设置不同水分处理进行田间试验,依据作物根区土壤水贮存量、生理指标及产量水平等参数,研究确定合理覆膜玉米沟灌灌溉制度。结果表明:沟灌玉米0~60cm土层土壤水变化幅度最大,20~40cm是主要贮水层,不同水分处理贮水量变幅为3~138.8m3/hm2;光合有效辐射呈抛物线形规律变化,灌水后均有所下降;蒸腾速率呈单峰型,水分处理不同蒸腾速率峰值出现时间不同;高水分处理玉米净光合速率较高,且有明显"午休现象";灌溉定额3 900m3/hm2时产量最高为15 300kg/hm2,2 700m3/hm2时产量最低为13 770kg/hm2,灌溉水量在一定范围内可增产,但超出上限时,产量与灌水不呈正相关关系。宁夏中部干旱带覆膜沟灌玉米合理灌溉制度为:全生育期灌水4次,灌水定额为975m3/hm2,灌溉定额3 900m3/hm2。  相似文献   

3.
地下水埋深对再生水灌溉的夏玉米生长影响   总被引:1,自引:0,他引:1  
为探讨地下水埋藏较浅地区再生水灌溉对夏玉米生长的影响,利用地中蒸渗仪控制不同地下水埋深(2、3和4 m),对夏玉米进行再生水灌溉试验,灌水量设900 m3/hm2和1200 m3/hm2二个处理,并与清水灌溉进行对比。试验表明,与对照相比,再生水灌溉叶面积指数和株高最大值出现时间要提前近10 d左右;不同地下水埋深的低水和高水处理叶面积指数变化趋势相同,都为埋深2 m>埋深3 m>埋深4 m;地下水埋深2 m3、m处理,低水和高水的株高非常接近,且都大于相应灌水量4 m地下水埋深处理;地下水埋深2 m、3 m处理再生水灌溉理论产量明显大于对照。  相似文献   

4.
针对宁夏干旱地区水资源贫乏,作物产量低的问题,采用膜下滴灌灌水和施肥的方式种植西瓜,研究不同灌溉定额及施氮量对西瓜生长、产量和水分利用效率的影响。试验结果表明:灌溉定额900 m3/hm2、施氮量225 kg/hm2的处理条件下茎粗最大为7.45 mm、产量最大为43.80t/hm2、水分利用效率为24.01 kg/m3;灌溉定额900 m3/hm2、施氮量300 kg/hm2的处理条件下株高最大为254.7 cm。综合考虑茎粗、株高、产量、水分利用效率和经济效益等多种因素,最优处理为T5(灌溉定额900 m3/hm2、施氮量225 kg/hm2),该处理最高产量可达43.80t/hm2,取得的经济效益最大。该研究结果能够为宁夏干旱地区节水种植西瓜提供理论依据和技术指导。  相似文献   

5.
膜下滴灌条件下制种玉米灌水制度研究   总被引:1,自引:0,他引:1  
根据2a气象数据计算种子玉米生产中的理论需水量,在此基础上设置膜下滴灌灌溉试验,共8个处理,设置45%、60%、75%三个田间持水率梯度,探讨膜下滴灌栽培模式下制种玉米最佳灌水量。结果表明,当玉米全生育期的最优灌溉定额为4 095m3/hm2时,产量最高为9 269.1kg/hm2,单方水产粮最高为2.26kg,此时用水最经济。其余处理产量、单方水产值均较低。该结果可为张掖市膜下滴灌条件下制种玉米合理灌溉提供依据。  相似文献   

6.
适宜的灌溉制度节水增产,能够改善盐分。不同灌溉制度对山西膜下滴灌玉米田土壤水盐及玉米生长、产量和水分利用效率的影响。以不灌溉(CK)为对照,设计3种灌溉处理,灌溉定额分别为675、900和1 125 m~3/hm~2,在玉米生育期内测定土壤含水率、土壤电导率、玉米株高、叶面积和产量,并计算灌溉水水分利用效率(Irrigation Water Use Efficiency,IWUE),研究不同处理对土壤水盐分布、玉米生长及产量的影响,结果表明:膜下滴灌土壤40 cm以内水分受灌水量影响较大,玉米需水关键期内,各处理间土壤水分差异不大;玉米收获后,土壤表层盐分有一定程度的降低,灌水量900和1 125 m~3/hm~2处理EC值比初始土壤EC值显著降低14%和28%(P0.05);玉米生长指标均随着灌水量增大而增大,但灌水量900和1 125 m~3/hm~2之间差异不明显,玉米产量以灌水量900和1 125 m~3/hm~2最高,二者无显著差异(P0.05),玉米IWUE随灌水量增大而减小。综合考虑产量和节水效应,建议灌水量900 m~3/hm~2为适宜的灌溉定额,该处理下灌水次数为4次。研究可为膜下滴灌技术在山西干旱地区的推广应用提供参考。  相似文献   

7.
2012年在西北干旱地区宁夏中部干旱带同心黑膜覆膜条件下,研究了洋葱喷灌方式灌溉量及灌水次数对洋葱产量的影响。结果表明:喷灌2 100m3/hm2处理鳞茎产量最高为77 414.1kg/hm2,较喷灌900m3/hm2处理增产28.50%,供水效率143.09kg/(hm2·mm),水分生产效率155.39kg/(hm2·mm),与喷灌900m3/hm2相比,水分生产效率提高7.53%。因此,优化出洋葱喷灌生产模式灌溉定额2 100m3/hm2,缓苗水300m3/hm2、叶旺长期600m3/hm2、喷灌2次,鳞茎生长期1 200m3/hm2、喷灌4次。  相似文献   

8.
以番茄为试验材料,设置固定隔沟灌和交替隔沟灌两种灌溉方式,每种灌溉方式设置2个灌水水平和2个施氮水平,共8个处理,分别测试每个处理番茄的产量、平均单果重、水分利用效率和品质,最后采用多指标综合评价方法提出优化的水氮耦合模式,结果表明:产量和水分利用效率最优的水氮耦合模式为T8(AFI),推荐灌水量为1 100m3/hm2,施氮量为150kg/hm2;品质最优的水氮耦合模式为T6(AFI),推荐灌水量为1 300m3/hm2,施氮量为150kg/hm2;综合最优的水氮耦合模式为T6(AFI),推荐灌水量为1 300m3/hm2,施氮量为150kg/hm2。  相似文献   

9.
沙地水肥耦合对玉米生长及产量的影响   总被引:1,自引:0,他引:1  
本试验针对沙地玉米生长设计灌溉定额及施氮量两个因素。灌溉定额分为3个水平,分别为2 925、2 250、1 590 m3/hm2;施氮量分为4个水平,分别为对照处理不施氮0、125、225和325 kg/hm2。低水平的四个施氮量:W3N0、W3N1、W3N2、W3N3,中水的四个施氮量W2N0、W2N1、W2N2、W2N3和高水的四个施氮量W1N0、W1N1、W1N2、W1N3。试验结论:土壤为沙地时,全生育期灌溉水量为2 925 m3/hm2,施氮量225~325 kg/hm2之间的水氮配合比对玉米的株高、茎粗、叶面积的生长最为有利。同一施肥水平下,增加灌水量有利于作物对氮肥的吸收,但灌水量太大,导致土壤养分向下迁移。合适的水肥配合比会使产量最优化,在W2N2处理下,即全生育期玉米灌水量为2250 m3/hm2施氮量为225 kg/hm2时产量最高,水分利用率最大,为本地沙地区节水灌溉适宜的水肥耦合的阈值区域。  相似文献   

10.
宁夏引黄灌区春玉米微咸水灌溉管理模式研究   总被引:1,自引:0,他引:1  
根据宁夏引黄灌区春玉米微咸水灌溉试验的数据结果,应用SWAP模型在田间尺度上对微咸水灌溉条件下春玉米田间土壤水盐运移规律和灌溉制度进行模拟,对拟定的各种灌溉方案进行评价。结果表明,率定与验证的SWAP模型可用于当地微咸水灌溉管理;25%降雨年型下,春玉米适宜灌水方案为生育期内灌2水(拔节水、抽雄水),灌溉定额为1200 m3/hm2;50%降雨年型下,春玉米适宜灌水方案为生育期内灌2水(拔节水、抽雄水),灌溉定额为1500 m3/hm2;75%降雨年型下,春玉米适宜灌水方案为生育期内灌3水(拔节水、抽雄水和灌浆水),灌溉定额为2400 m3/hm2。  相似文献   

11.
通过基于HYDRUS-2D模型所建模拟模型,模拟了不同土壤、灌水量和隔畦宽度情况下隔畦中不同深度土壤水分变化情况.基本结论为:①壤土侧渗效果最好,在灌水4~5 d后,灌溉畦与非灌溉畦(隔畦)土壤含水量基本接近,可达到隔畦灌溉的目的;②隔畦中湿润锋距离与灌水后时间呈线形关系;灌水畦灌水量越大,在窄畦中的湿润锋越远,但增大到1 050 m3/hm2以后因渗漏的增加,湿润锋距离增加不太明显;③综合考虑节水率、产量等因素,灌水量在600~900 m3/hm2之间,畦宽选择120 cm左右,灌水利用率最佳,与田间结果一致.项目研究结果为制定隔畦灌溉制度提供了基本参考依据.  相似文献   

12.
The effect of water stress on corn yield was studied in a salinity experiment and in a drought experiment. The plant water status was determined by measuring the pre-dawn leaf water potential regularly during the whole growing season and expressed by the water stress day index (WSDI). The yield response of corn did not differ under salinity and drought conditions. The WSDI is a useful indicator for determining crop-response to salinity and drought.  相似文献   

13.
通过田间试验,以郑单958和浚单20为试材,研究了不同密度和不同灌水处理对玉米产量和水分利用效率的影响。结果表明:不同灌水处理对产量构成影响较小;不同密度下玉米两品种的穗数和穗粒数差异显著;两品种玉米高密度比低密度处理产量平均增加16.89%;抗旱品种郑单958产量受灌水量的影响较小;浚单20灌水比不灌水处理平均增产11.40%。玉米两品种处理水分利用效率一般以不灌水处理较高,灌水处理水分利用效率均值比0水处理降低30.37%。因此,在水资源较缺乏的太行山山前平原区,选用抗旱品种进行合理密植并灌一水,对实现玉米节水与高产的统一有着重要意义。  相似文献   

14.
The depleted fraction, defined as the ratio of ETactual over total inflow (P + Vc), relates parameters of the water balance of an irrigated area with each other in such a way that the (water) manager obtains information on the rate of change of water stored in the area (soil moisture and groundwater). If the annual average of the depleted fraction equals about 0.6 water storage in the area is stable, while water is stored for lower values of the depleted fraction. If the value of the depleted fraction exceeds about 0.6, the volume of water stored in the area decreases. This decrease is partly due to natural drainage and partly due to capillary rise into the root zone of the irrigated crop. Despite this capillary rise, the actual evapo-transpiration drops below the potential ET-value. For most crops, a decrease of ET by about 25% would result in a higher productivity in terms of yield per cubic meter water. However, the yield per hectare (and thus farm income) would decrease. Management of an irrigation system is recommended in such a way that the monthly values of the depleted fraction range is between 0.5 and 0.8. Such a management rule would provide sufficient water for leaching (at the 0.5 side of the range) and provide high crop yield per unit water consumed (at the 0.8 side).  相似文献   

15.
不同水盐胁迫对番茄生长发育和产量的影响研究   总被引:1,自引:1,他引:0  
【目的】探究番茄植株对不同水盐胁迫情景的响应,为合理制定盐碱化土壤下的灌溉制度提供科学依据。【方法】以粉欧宝番茄品种为研究对象,开展水盐对番茄生长发育影响的盆栽试验。试验采用完全随机布置,设置3个水分水平(W1-充分灌溉、W2-1/2的W1灌水量、W3-干旱复水)和2个盐分水平(S1-无盐和S2-0.3%含盐量),每个处理4个重复,测定了番茄耗水、干物质和产量指标,分析了不同水盐胁迫对番茄植株生长发育与产量的影响。【结果】与充分灌溉W1相比,W2水平的番茄植株耗水、干物质、植株含水率、叶质量、产量、单果质量显著减少。W3水平的植株耗水量和叶茎比显著减少,但单株干质量与鲜干比所受影响不大;单果鲜质量与干质量显著减小,但坐果率提高导致产量有所增加。盐分处理的番茄植株耗水量、单株干质量、鲜干比、叶茎比、果实总产量、单果鲜质量与干质量均小于无盐处理。水分胁迫显著影响叶片生长和单个果实发育,盐分胁迫抑制植株的生长发育及产量形成。【结论】干旱复水与无盐处理组合(W3S1)下番茄植株表现出了较好的生长发育状况和产量水平,可用于最优调亏灌溉制度的制定。  相似文献   

16.
以黄淮海平原地下微咸水为研究材料,通过实验室模拟,采用冻融法,研究地下微咸水冰晶融冻过程中融水含盐量以及离子动态变化特征及其之间的相互关系。结果表明,融冰初期(进程10%)融水含盐量高达14.71g/L。随着融冻进程融水含盐量及Cl-、SO24-、CO23-、HCO3-、Na+、Mg2+、K+等离子均呈逐渐递减趋势,且与融解进程呈极显著指数相关(P<0.01),相关程度均达90%以上;Ca2+则呈现先增加后降低的趋势,与融冰进程呈显著抛物线关系。当500mL地下咸水冰晶融解掉79mL水后,剩余水含盐量将会低于2g/L,融掉216.5mL时,可将盐分控制在1g/L以下。融冰前期,离子主要以Na+、Mg2+、Cl-为主,随着融冻进程逐渐演变为以Na+、Mg2+、Cl-、SO24-为主。地下咸水冰晶融冻时含盐量与离子变化具有高度一致性,冰晶融冻技术可达到地下咸水脱盐和控制离子组成的双重目的。  相似文献   

17.
In most cases, when calculating soil water availability, only thewater content is considered. The effect of salinity on the wiltingpoint is neglected. The objective of this work is to use asimulation model (CERES-maize) in order to predict cornyields as a function of water salinity under severalenvironmental, agrotechnical, and plant characteristics. A modelis presented in which the wilting point is a function of the soilsalt content. At high salinity, the water content at wilting pointis higher than at low salinity, resulting in an insufficient amountof available water and, therefore, a reduced yield. The modelwas used to simulate several theoretical and experimentalsituations for forage corn and grain corn. Simulation resultsshowed that nitrogen fertilization increases the salinity thresholdvalue and the yield sensitivity (rate of yield reduction per unitof salinity). The also showed that forage corn is more sensitiveto salinity than grain corn. If the soil is not leached, a heaviersoil texture has a higher salinity threshold value. On the otherhand, if the soil is leached, the soil texture has no influence onthe salinity threshold value and the yield is less sensitive tosalinity in sandy soils. The determination coefficient (r2= 0.75) indicated that the results of the simulations were in goodagreement with the field data.  相似文献   

18.
龚郑锋 《农业工程》2021,11(12):108-113
为研究不同生育期干旱胁迫对玉米籽粒灌浆及产量的影响,分别设置正常水分、拔节期干旱、抽雄期干旱和灌浆初期干旱4个处理,研究玉米干物质积累、灌浆特性、淀粉相关酶活性及产量的变化特征。结果表明:干旱显著降低玉米干物质积累量,抽雄期和灌浆初期干旱显著降低花后干物质积累量和贡献率;干旱显著降低籽粒质量和灌浆速率,抽雄期干旱对后期籽粒质量和灌浆速率影响最大;干旱显著降低结合态淀粉合成酶(GBSS)、可溶性淀粉合成酶(SSS)、蔗糖合成酶(SS)和蔗糖磷酸合成酶(SPS)活性;干旱对产量的影响主要是增加了秃尖长、减少了行粒数,3个时期干旱胁迫产量分别降低15.15%、33.11%和22.00%。因此,拔节期、抽雄期和灌浆初期玉米对水分的需求较为敏感,对产量影响较大,尤其是在玉米抽雄期,要确保水分供应,以保证玉米产量。   相似文献   

19.
Summary Canopies of 22-year-old Santa Rosa plum trees irrigated with mini-sprinklers below the canopy with nonsaline (0.3 dS/m) water were sprayed weekly during one irrigation season with water having six levels of salinity (0.3, 1.1, 2.1, 3.3, 4.5, and 6.8 dS/m) to evaluate the extent of leaf injury, foliar absorption of Cl and Na, and yield response. Recognizable leaf injury was caused by spray water containing 29 mol/m3 of chloride and 15 mol/m3 of sodium. Severe leaf damage occurred when the leaf chloride and sodium concentrations exceeded 300 and 125 mmol/kg (dry weight), respectively. These concentrations were higher than those causing foliar damage on other trees in the same orchard which had been irrigated below the canopy with water having the same salinity as that sprayed on the canopy. No residual foliar injury was observed during the irrigation season following the year when the spray treatments were applied. Fruit yield measured six weeks after treatments were initiated was unaffected. In the following 2 years, yield was reduced by the highest salinity levels, even though the salt spray treatments were not continued and no foliar injury was visible.  相似文献   

20.
Two chickpea varieties, differing in drought tolerance, were grown in lysimeters filled with clay, and were irrigated with waters of three different salinity levels. Under non-saline conditions, both varieties, slightly differing in pre-dawn leaf water potential during the growth period, gave almost the same yield.Salinity had a slight effect on the leaf water potential and the osmotic adjustment. Both were slightly higher for the drought tolerant variety, but much lower in comparison with sugar beet, tomato and lentil. The drought tolerant variety showed an earlier senescence in leaf and dry matter development and flowering which were accelerated by salinity. The drought sensitive variety, however, showed under slightly saline conditions (ECe=2.5 dS/m) from 135 days after sowing onwards a different behaviour by the growth of new leaves and flowers, a delay in senescence, leading to the same yield as under non-saline conditions. Under saline conditions (ECe=3.8 dS/m) the drought sensitive variety showed the same yield reduction of about 70% as the drought tolerant variety.  相似文献   

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