共查询到20条相似文献,搜索用时 31 毫秒
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[目的]为了更好地为风沙土膜下滴灌灌溉制度的制定提供理论依据。[方法]通过田间试验对不同灌溉水量条件下风沙土地区膜下滴灌玉米生长和产量的影响进行研究。[结果]灌溉水量对玉米株高、茎粗、叶面积指数(LA,)和单株地上干物质重等营养生长指标影响较小;穗长、穗粗、行粒数、百粒重、穗粒重、穗重等产量构成性状和产量均随着灌水量的增加先增大后减小,灌溉水量为75%Er时产量最高,达到7.67t/hm3;水分利用效率(WUE)随着灌溉水量的增加线性下降,25%ET时WUE最大,为1.30kg/m3。[结论]在风沙土地区,玉米膜下滴灌灌溉水量宜控制在25%ET~75%ET。 相似文献
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葡萄园水碳通量对灌溉、降雨和霜冻的响应 总被引:1,自引:1,他引:0
为分析灌溉、降雨、霜冻对西北旱区葡萄园水碳通量的影响,以我国西北干旱区葡萄园为例,采用涡度相关系统和茎流计对降雨、灌溉和霜冻前后的葡萄园水碳通量进行连续对比观测。结果表明:1)降雨后,葡萄园蒸散发量迅速增加,随着时间推移逐渐降低;日峰值出现的时间由14:00推迟到15:00,葡萄园蒸腾量呈缓慢增加趋势;2)灌溉后,葡萄园蒸散发量先逐日增加,达到峰值后再逐渐减小;3)灌溉和降雨均明显增加了葡萄园的碳汇量;4)霜冻后,葡萄叶片几乎死亡,蒸腾量急剧减小接近于0,净生态系统交换量的波动迅速减缓,葡萄园转入碳源阶段。 相似文献
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Experimental Investigation of Soil Evaporation and Evapotranspiration of Winter Wheat Under Sprinkler Irrigation 总被引:1,自引:0,他引:1
YU Li-peng HUANG Guan-hua LIU Hai-jun WANG Xiang-ping WANG Ming-qiang 《中国农业科学(英文版)》2009,8(11):1360-1368
Sprinkler irrigation is one of the typical irrigation technologies used for the winter wheat-summer maize double cropping system in the North China Plain. To evaluate the evapotranspiration (ET) of winter wheat under sprinkler irrigation in Beijing area, field experiments were conducted in growing seasons through 2005-2008, in the experimental station located in Tongzhou County, Beijing, China, with different irrigation depths. Results indicated that a relatively large variation of soil water content occurred within 0-40 cm soil layer. The seasonal ET of winter wheat generally increased with increasing irrigation amount, while the seasonal usage of soil water had a negative relationship with irrigation amount. Soil evaporation (Es) was about 25% of winter wheat ET during the period from reviving to maturity. Es increased while Es/ET decreased with increasing irrigation amount. Sprinkler irrigation scheduling with relatively large irrigation quota and low irrigation frequency can reduce Es and promote the irrigation water use efficiency. 相似文献
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利用微咸水膜下灌溉是缓解干旱区农业灌溉资源短缺的有效途径之一,分析不同矿化度水源膜下滴灌对土壤盐分分布及作物生长的影响对于确定灌溉水源矿化度阈值具有重要意义。开展4 a不同梯度矿化度水源膜下滴灌棉花测坑试验,设置6个处理矿化度分别为1 g/L(CK)、2 g/L(A)、3 g/L(B)、4 g/L(C)、5 g/L(D)和6 g/L(E),分析不同梯度矿化度水源膜下滴灌土壤盐分累积及棉花生长特征,确定微咸水膜下滴灌棉花灌溉矿化度阈值。结果表明:2019-2022年,0~100 cm平均土壤电导率以每年0.920dS/m、0.995 dS/m、1.196 dS/m和1.188 dS/m的速率呈线性增长的趋势。随着灌溉年限增加,不同梯度微咸水膜下滴灌下土壤电导率呈现增加趋势。5 g/L和6 g/L处理土壤盐分累积最大,分别为38.70%和39.19%;灌水12 h后,宽行表层20~40 cm土壤盐分累积最为明显,土壤电导率为0.30~2.1 dS/m;窄行土壤盐分在40~60 cm土层处出现累积,土壤电导率为1.26~1.93 dS/m。矿化度为3 g/L水源膜下滴灌棉花土壤盐分累积量较小... 相似文献
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应用农田水量平衡原理计算三种蔬菜的需水量和作物系数 总被引:13,自引:2,他引:13
根据田间水分和肥料最优控制下测定的土壤水分,利用农田水量平衡原理分别计算了花椰菜、苋菜和菠菜生长期内的作物需水量。根据作物需水量和气象资料计算的参考作物蒸散量,计算3种蔬菜在不同生育期内的作物系数。结果表明,花椰菜、苋菜和菠菜在整个生长期内的需水量分别为223.8mm,144.9mm和148.1mm;作物系数的平均值分别是0.68,0.94和0.65;除苋菜的作物系数与叶面积指数的拟合关系相关性不显著外,花椰菜和菠菜的作物系数与叶面积指数呈对数函数关系。 相似文献
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Hongzhan Lü Weili Liang Guiyan Wang David J. Connor Glyn M. Rimmington 《Frontiers of Agriculture in China》2009,3(2):109-121
The test on the model with data collected from two years’ field experiments revealed an ability to satisfactorily simulate
crop parameters such as LAI, biomass accumulation and partitioning, yield, and variables influencing crop growth and development
as nitrogen uptake by crops and partitioning in different organs, and dynamics of soil water and nitrogen including infiltration
and leaching. With the model, crop yield, water use efficiency (WUE), nitrogen use efficiency (NYE) and water-nitrogen leaching
at specific soil layers under various water and nitrogen management practices were simulated to provide data used as references
for designing sustainable nitrogen and water management practices.
The outputs of the simulated experiment with various treatments of irrigation and nitrogen application indicated that crop
yield was closely related to water and nitrogen application, crop water use was positively related to irrigation amount, and
nitrogen fertilization could improve the crop water use and WUE within certain limits. This is a valuable evidence to be considered
in water-saving farming. Nitrogen uptake had a positive relation to nitrogen application, while irrigation to some extent
improved its uptake by crops and hence increased NYE. Additionally, irrigation and fertilization had great effects on nitrogen
leaching. Thus, in order to improve WUE and NYE, the model showed how nitrogen application and irrigation should be well coordinated. 相似文献
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以盆栽黄冠梨幼树为试材,研究不同土壤水分含量(SWC)对光合作用的影响规律,以确定梨园节水灌溉适宜的土壤水分调控指标.结果表明,SWC为50.6%时水分利用效率(WUE)最高;SWC由97.9%降至50.6%时,气孔导度(Gs)、蒸腾速率(Tr)与净光合速率(Pn)均下降,但Tr的下降幅度大于Pn的下降幅度而导致WUE的升高.SWC由50.6%降至19.7%时,WUE降低,降低的主要原因在于羧化效率下降导致Pn的大幅度降低.干旱复水后,Pn和Tr均有较大的回升,复水第2天后SWC为98.5%时,Pn和Tr大幅度的回升,但Tr回升的幅度更大,导致此时的WUE降为整个试验阶段的最低;复水第5天SWC为66.8%时,Pn和WUE均低于对照,这可能与叶片羧化功能受损后Pn不易恢复有关. 相似文献
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Optimization of water and nitrogen management for surge-root irrigated apple trees in the Loess Plateau of China
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The Loess Plateau is one of the main regions for growing apple trees in China, but a shortage of water resources and low utilization of nitrogen have restricted its agricultural development. A 2-year field experiment was conducted which included three levels of soil water content(SWC), 90–75%, 75–60%, and 60–45% of field capacity, and five levels of nitrogen application(N_(app)), 0.7, 0.6, 0.5, 0.4 and 0.3 kg/plant. The treatments were arranged in a strip-plot design with complete randomized blocks with three replications. For both years, the water and N_(app) had significant(P0.05) effects on leaf area index(LAI), yield, water use efficiency(WUE) and nitrogen partial factor productivity(NPFP) while the interaction effect of water and N_(app) on yield, WUE and NPFP was significant(P0.05) in 2018, and not in 2017. For the same SWC level, WUE first increased, then decreased as N_(app) increased, while NPFP tended to decrease, but the trend of LAI with different N_(app) was closely related to SWC. At the same N_(app), the LAI increased as SWC increased, while the WUE and NPFP first increased, then decreased, but the yield showed different trends as the SWC increased. The dualistic and quadric regression equations of water and N_(app) indicate that the yield, WUE and NPFP cannot reach the maximum at the same time. Considering the coupling effects of water and N_(app) on yield, WUE and NPFP in 2017 and 2018, the SWC level shall be controlled in 75–60% of field capacity and the N_(app) is 0.45 kg/plant, which can be as the suitable strategy of water and N_(app) management for the maximum comprehensive benefits of yield, WUE and NPFP for apple trees in the Loess Plateau and other regions with similar environments. 相似文献
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喷灌冬小麦耗水与棵间蒸发试验 总被引:1,自引:0,他引:1
【目的】研究喷灌条件下冬小麦的耗水规律,指导田间灌溉实践。【方法】在北京地区2005-2008年3个冬小麦生长季节,开展不同喷灌水量条件下土壤水分分布、冬小麦耗水和棵间蒸发特性的试验研究,并分析影响棵间蒸发的主要因素。【结果】喷灌条件下,0~40 cm土层土壤的含水量受灌溉水量影响较明显,耗水量随着灌水量增加而增加。返青至收获期,冬小麦棵间蒸发为耗水量的25%左右,棵间蒸发随着灌水量的增大而增大,但棵间累积蒸发与作物耗水量之比随之而下降。【结论】适当加大灌水定额,减少灌溉次数,可在一定程度上抑制土壤的无效蒸发,提高灌溉水的利用率。 相似文献
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基于DSSAT模型的河南省冬小麦需水量分析 总被引:2,自引:0,他引:2
为定量评估河南省不同生态地点冬小麦需水量变化特征,应用DSSAT模型模拟了充分灌溉、雨养不灌溉条件下河南省15个地点连续10 a(2003—2012年)冬小麦产量、田间蒸散量、作物蒸腾量、土壤蒸发量等,分析了灌溉增产以及水分生产率的分布规律,并计算河南省不同地点平均需水量和缺水量。结果表明:充分灌溉条件下,河南省15个生态地点10 a间冬小麦平均产量介于7 847~9 565 kg/hm~2,作物蒸腾量介于319~380 mm,土壤蒸发量介于96~166 mm,田间蒸散量介于445~539 mm,水分生产率介于1.67~1.98 kg/(hm~2·m~3);雨养不灌溉条件下,15个生态地点10 a间冬小麦平均产量介于1 927~6 260 kg/hm~2,作物蒸腾量介于66~244 mm,土壤蒸发量介于120~195 mm,田间蒸散量介于209~370 mm,水分生产率介于0.79~2.17 kg/(hm~2·m~3)。15个生态地点10 a间灌溉增产介于1 594~6 698 kg/hm~2,总体呈中北部较高南部较低。15个生态地点10 a间需水量介于395~452 mm,河南省中东部及南部需水量相对较低;缺水量介于76~282 mm,整体呈北高南低。研究结果可为河南省冬小麦水分定量化管理措施的制定提供参考。 相似文献
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为验证超前决策灌溉模型在土壤栽培中的科学性,筛选基于超前决策灌溉模型的最优灌溉量组合,以Penman-Monteith模型为对照(PM处理),分别在番茄的开花坐果期和果实膨大期设置超前决策灌溉模型计算灌溉量(ET)的3个水平(0.8 ET、1.0 ET、1.2 ET),共计10个处理,通过春秋两茬试验,分析比较不同灌溉模型对土壤含水量、番茄生理指标、产量、品质与水分利用效率的影响,并利用熵权-TOPSIS法评价不同处理番茄的综合指标。结果表明:与对照相比,超前决策灌溉模型处理土壤含水量的波动较小,光合能力、植株产量与水分利用效率显著提高。运用熵权-TOPSIS综合分析法进行排序,T2-3处理(开花坐果期使用1.0 ET灌溉,果实膨大期使用1.2 ET进行灌溉)排第1位,秋茬番茄PM处理(使用PM模型进行灌溉)排在第8位,春茬温室番茄PM处理排在第10位。秋茬与春茬温室番茄最优处理T2-3相较于PM处理,叶片的净光合速率提高约9.7%和24.3%,蒸腾速率降低约16.5%和14.6%,产量和水分利用效率分别提升了4.7%、8.7%与0.8%、9.5%。研究结果表明在温室番茄的土壤栽培中,无论是春季还是秋季,超前决策灌溉模型比PM模型灌溉精度高;且在开花坐果期使用1.0 ET灌溉、果实膨大期使用1.2 ET进行灌溉为超前决策灌溉模型最优的灌溉量组合。 相似文献
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海河平原冬小麦生产与水资源匮乏的矛盾十分突出,亟需建立限水灌溉制度,实现丰产与水分高效的协调统一。于2018—2020年冬小麦生长季,选取旱地组(石麦22、衡观35和冀麦418)和水地组(石农086、冀麦585和石新828)2种类型小麦品种,设置适期播种和晚播2个播期以及春季2次灌水、不灌水和春3、4、5、6叶龄1次灌水处理。研究不同处理土壤水分动态变化及冬小麦产量形成特征。结果表明: 春季限水灌溉下,0—60 cm土层为主要供水层,其含水量(SWC60)变化显著影响小麦产量形成;春4叶龄为冬小麦春季1次灌水的最佳灌溉时期,灌水前干旱程度较轻,灌水后直至乳熟末期SWC60才低于60%,干旱胁迫也相对较轻;春季限水灌溉下,冬小麦产量显著降低,旱地组品种产量降幅低于水地组品种。不同春季叶龄1次灌水处理总体表现为春4叶龄灌水产量降幅最小,平均减产约10%。春季1次灌水晚播处理的产量水平与对应的适期播种处理无显著差异。春4叶龄灌水处理产量和水分利用效率(WUE)显著高于其他春季1次灌水处理,其单位面积穗数、穗粒数和千粒重更为均衡协调,最终在实现7 502.9~8 050.0 kg·hm?2产量水平的同时,WUE达17.5 ~20.1 kg·hm?2·mm?1,较春季2次灌水节水70.1 mm。上述研究结果为构建精量高效的小麦春季限水灌溉制度提供了依据。 相似文献
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用彭曼(H.L.Peaman)法计算了全省94个县市的参考作物蒸散量,再结合作物系数Kc值计算出小麦需水量ETm;根据小麦生育期间的降水量得出了小麦的灌溉需水量(ETm─降水量)。根据以上数据绘制了山西省小麦需水量图和灌溉需水量图,并对各地区的小麦需水量进行了简要评价。 相似文献
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温室青椒开花座果初期耗水规律与影响因素分析 总被引:2,自引:0,他引:2
通过盆栽试验,研究了膜下滴灌及滴灌情况下温室青椒开花座果初期的耗水规律,分析了两种情况下土壤含水率、相对湿度、温度和叶面积指数(LAI)对青椒开花座果初期耗水量的影响。结果表明,膜下滴灌、滴灌情况下,植株平均耗水量分别为0.87和2.0mm/d,地膜覆盖使耗水量减少了51.3%;利用蒸发皿测定的水面蒸发量能够很好地估算温室内的青椒耗水量,两种情况下温室青椒开花座果初期蒸发皿系数分别为0.39和0.82;土壤含水率、温度与青椒耗水量同步变化,相对湿度与耗水量异步变化,叶面积指数(LAI)的增大使耗水量增加。 相似文献
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为明确不同水分处理对两种机采种植模式棉花蒸散发特征、产量形成及品质变化的影响,于2020-2021开展田间小区试验,设4个灌溉处理3 600 m3/hm2(D1)、4 500 m3/hm2(D2)、5 400 m3/hm2(D3)、6 300 m3/hm2(D4),2种机采模式等行距种植(R1)和宽窄行种植(R2)。结果表明:2种机采种植模式土壤蒸发量(Es)、蒸散量(ET)、Es/ET均随灌水量的增加而增加;不同灌水处理土壤日蒸发量在灌溉后1~4 d处于较高水平,R1较R2分别高6.98%、7.55%、8.53%、7.19%。年均蒸散量4个灌水处理R1分别为397.6 mm、465.2 mm、547.2 mm、665 mm, R2分别为412.5 mm、482.1 mm、563.5 mm、684.5 mm, R2较R1分别高3.76%、3.64%、2.96%和2.94%。4个灌水处理Es/ET比值R1为27.4... 相似文献