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1.
Cotton is the main economically important crop in Xinjiang, China, but soil salinization and shortage of water and nutrients have restricted its production. A field experiment was carried out in the salinity-affected arid area of Northwest China from 2018 to 2019 to explore the effects of nitrogen and water regulation on physiological growth, yield, water and nitrogen use efficiencies, and economic benefit of cotton. The salinity levels were 7.7 (SL) and 12.5 dS/m (SM). Drip irrigation was used with low, medium and adequate irrigation levels representing 60%, 80% and 100% of cotton crop water demand, respectively, and three nitrogen applications, i.e., 206, 275 and 343 kg/hm2, accounting for 75%, 100% and 125% of local N application, respectively were used. The multi-objective optimization based on spatial analysis showed that, at SL salinity, water use efficiency (WUE), nitrogen use efficiency (NUE), economic benefit and yield simultaneously reached more than 85% of their maxima at 379.18-398.32 mm irrigation and 256.69-308.87 kg/hm2. At SM salinity, WUE, yield and economic benefit simultaneously reached more than 85% of their maxima when irrigation was 351.24-376.30 mm and nitrogen application was 230.18-289.89 kg/hm2. NUE, yield and economic benefit simultaneously reached their maxima at 428.01-337.72 mm irrigation, and nitrogen application range was 222.14-293.93 kg/hm2. The plants at SL salinity had 21.58%-46.59% higher WUE rates, 14.91%-34.35% higher NUE rates and 20.71%-35.34% higher yields than those at SM salinity. The results are of great importance for the nutrient and water management in cotton field in the arid saline area. 相似文献
2.
氮肥类型对夏玉米及后作冬小麦产量与水、氮利用的影响 总被引：2，自引：0，他引：2
研究了华北平原夏玉米季施用不同类型氮肥对当季与后作冬小麦及周年产量与水、氮利用的影响,结果表明:(1)随施氮量增大,夏玉米产量、耗水量与水分利用效率(WUE)增大,氮肥利用率(NUE)降低。夏玉米WUE与NUE受到氮肥类型的影响,WUE以复合肥处理较大,NUE以包膜尿素和复合肥较高,且存在较明显的基因型差异,WUE以郑单958较大,NUE以农大108较大;(2)夏玉米季施氮使冬小麦氮生理效率降低,氮肥效率增大,并显著影响冬小麦产量和WUE,但因夏玉米季品种、氮肥类型与施氮量不同而表现有差异。夏玉米季氮肥后效明显,但氮肥类型间差异显著,一般以尿素处理及包膜尿素与复合肥高N处理较大;(3)夏玉米—冬小麦轮作制度下,两季总产量、总氮素累积量、总耗水量及水、氮利用效率明显受到夏玉米季氮肥类型与施氮量的影响,且受到夏玉米基因型的影响。 相似文献
3.
河套灌区春小麦高产栽培水氮高效利用研究 总被引：1，自引：0，他引：1
在内蒙古河套灌区解放闸灌域沙壕渠实验站,通过田间试验,对节水灌溉模式(拔节+抽穗2水)和常规充分灌溉模式(分蘖+拔节+抽穗+灌浆4水)下,不同施氮量对春小麦产量形成、水分利用和氮素利用等方面进行了研究.结果表明:2水与4水处理间小麦产量及其构成因素均无显著差异,而水分利用效率(WUE)比4水处理提高7.8%.在较低施氮... 相似文献
4.
水氮耦合对滴灌复播大豆干物质积累氮素吸收及产量的影响 总被引：3，自引：0，他引：3
为探明不同水氮组合对复播大豆干物质积累、氮素吸收及产量的影响,于2013年7—10月在新疆伊宁县进行了不同滴灌量与施氮量的裂区田间试验。滴灌量为主因子,分设3 000 m3·hm-2(W1)、3 600 m3·hm-2(W2)、4 200 m3·hm-2(W3)、4 800 m3·hm-2(W4)四个灌水梯度;施氮量为副因子,设0 kg·hm-2(N0)、150 kg·hm-2(N1)、300 kg·hm-2(N2)三个水平。结果表明:同一施氮量条件下,随着滴灌量的增加各施氮处理干物质积累平均速率、干物质积累持续时间及氮素吸收量基本表现为"先增后降"的趋势,且均在W3处理(4 200 m3·hm-2)达到最大;在低水量(W1)条件下增加氮肥的投入,有利于增加复播大豆干物质积累,提高复播大豆氮素吸收量,进而提高复播大豆产量,但降低了氮素籽粒生产效率;水分充足时适量增施氮肥能促进大豆干物质的积累,增加植株氮素的吸收量,增加氮素籽粒生产效率,而过量追施氮肥,阻碍根系吸收氮素进入植株体内,降低氮素的利用效率,且W3N1组合条件下,干物质积累量、植株氮素吸收量、产量均达到最大,产量达到3 741.23 kg·hm-2,分别比低水低肥处理(W1N0)、高水高肥处理(W4N2)增加了54.30%、17.02%。 相似文献
5.
为揭示长期咸水滴灌对灰漠土物理化学特性及棉花生长的影响,研究了咸水灌溉11 a后土壤盐分、容重、水力特性、棉花耐盐生理特征及产量。试验设置3个灌溉水盐度水平:0.35 dS·m~(-1)(淡水)、4.61 dS·m~(-1)(微咸水)和8.04 dS·m~(-1)(咸水)。研究表明:与淡水灌溉相比,微咸水和咸水灌溉显著增加土壤容重、盐分、pH值和土壤含水量,显著降低土壤孔隙度、全氮和有机质含量;土壤饱和导水率在微咸水和咸水灌溉处理下分别较淡水处理降低45%和60%,体积含水率随着灌溉水盐度的增加而增大;与淡水灌溉相比,微咸水和咸水灌溉显著降低棉花叶面积、叶水势、气孔导度、叶绿素含量和干鲜质量比,其中叶水势分别较淡水处理下降43.34%和63.46%;微咸水和咸水灌溉显著增加棉花叶片相对电导率和丙二醛含量,同时SOD、POD和CAT活性也显著增加,脯氨酸含量分别较淡水灌溉增加69.52%和212%;棉花总生物量在微咸水和咸水灌溉处理下分别较淡水灌溉处理降低14.15%和32.88%;籽棉产量分别较淡水灌溉降低12.6%和25.7%。综上所述,长期的微咸水和咸水灌溉显著增加土壤盐分含量、降低土壤养分含量,土壤水分的可利用性也显著下降,导致棉花生物量和产量降低。 相似文献
6.
Optimal use of water and fertilizers can enhance winter wheat yield and increase the efficiencies of water and fertilizer usage in dryland agricultural systems.In order to optimize water and nitrogen(N)management for winter wheat,we conducted field experiments from 2006 to 2008 at the Changwu Agro-ecological Experimental Station of the Chinese Academy of Sciences on the Loess Plateau,China.Regression models of wheat yield and evapotranspiration(ET)were established in this study to evaluate the water and fertilizer coupling effects and to determine the optimal coupling domain.The results showed that there was a positive effect of water and N fertilizer on crop yield,and optimal irrigation and N inputs can significantly increase the yield of winter wheat.In the drought year(2006–2007),the maximum yield(Ymax)of winter wheat was 9.211 t/hm2for the treatment with 324 mm irrigation and 310 kg/hm2N input,and the highest water use efficiency(WUE)of 16.335 kg/(hm2 mm)was achieved with198 mm irrigation and 274 kg/hm2N input.While in the normal year(2007–2008),the maximum winter wheat yield of 10.715 t/hm2was achieved by applying 318 mm irrigation and 291 kg/hm2N,and the highest WUE was 18.69kg/(hm2 mm)with 107 mm irrigation and 256 kg/hm2N input.Crop yield and ET response to irrigation and N inputs followed a quadratic and a line function,respectively.The optimal coupling domain was determined using the elasticity index(EI)and its expression in the water-N dimensions,and was represented by an ellipse,such that the global maximum WUE(WUEmax)and Ymax values corresponded to the left and right end points of the long axis,respectively.Considering the aim to get the greatest profit in practice,the optimal coupling domain was represented by the lower half of the ellipse,with the Ymax and WUEmax on the two end points of the long axis.Overall,we found that the total amount of irrigation for winter wheat should not exceed 324 mm.In addition,our optimal coupling domain visually reflects the optimal range of water and N inputs for the maximum winter wheat yield on the Loess Plateau,and it may also provide a useful reference for identifying appropriate water and N inputs in agricultural applications. 相似文献
7.
Soil water and salt distribution under furrow irrigation of saline water with plastic mulch on ridge 总被引：3，自引：0，他引：3
Furrow irrigation when combined with plastic mulch on ridge is one of the current uppermost water-saving irrigation technologies for arid regions.The present paper studies the dynamics of soil water-salt transportation and its spatial distribution characteristics under irrigation with saline water in a maize field experiment.The mathematical relationships for soil salinity,irrigation amount and water salinity are also established to evaluate the contribution of the irrigation amount and the salinity of saline water to soil salt accumulation.The result showed that irrigation with water of high salinity could effectively increase soil water content,but the increment is limited comparing with the influence from irrigation amount.The soil water content in furrows was higher than that in ridges at the same soil layers,with increments of 12.87% and 13.70% for MMF9(the treatment with the highest water salinity and the largest amount of irrigation water) and MMF1(the treatment with the lowest water salinity and the least amount of irrigation water) on 27 June,respectively.The increment for MMF9 was gradually reduced while that for MMF1 increased along with growth stages,the values for 17 August being 2.40% and 19.92%,respectively.Soil water content in the ridge for MMF9 reduced gradually from the surface layer to deeper layers while the surface soil water content for MMF1 was smaller than the contents below 20 cm at the early growing stage.Soil salinities for the treatments with the same amount of irrigation water but different water salinity increased with the water salinity.When water salinity was 6.04 dS/m,the less water resulted in more salt accumulation in topsoil and less in deep layers.When water salinity was 2.89 dS/m,however,the less water resulted in less salt accumulation in topsoil and salinity remained basically stable in deep layers.The salt accumulation in the ridge surface was much smaller than that in the furrow bottom under this technology,which was quite different from traditional furrow irrigation.The soil salinities for MMF7,MMF8 and MMF9 in the ridge surface were 0.191,0.355 and 0.427 dS/m,respectively,whereas those in the furrow bottom were 0.316,0.521 and 0.631 dS/m,respectively.The result of correlation analysis indicated that compared with irrigation amount,the irrigation water salinity was still the main factor influencing soil salinity in furrow irrigation with plastic mulch on ridge. 相似文献
8.
垄作和灌水量对河西绿洲灌区啤酒大麦的影响 总被引：2，自引：0，他引：2
在甘肃河西绿洲灌区,通过田间试验研究了不同栽培模式与灌溉量组合对啤酒大麦产量、水分利用效率(WUE)和土壤肥力的影响.结果表明:当灌溉量为330 mm时,垄作沟内覆草模式产量较对照增产695 kg/hm2,增产率为10.2%;在灌溉量为270 mm时,垄作和垄作沟内覆草处理较对照没有减产,可节水60 mm;不同栽培模式... 相似文献
9.
以早熟杂交棉石杂2号为材料,在花铃期进行了7个水分处理和4个氮素处理的水氮互作对杂交棉花产量和水分利用效率影响的大田试验。研究结果表明,在不施氮(N0)情况下,花铃期轻旱和中旱显著降低了棉花产量。在低频小灌量(5 d-18 mm)条件下,施氮籽棉产量差异不显著;在高频大灌量(3 d-30 mm)水分处理中,随着施氮量的增加,籽棉产量显著下降;在对照(75%FC),高频小灌量(3 d-18 mm)和低频大灌量(5 d-30 mm)三个水分处理中,水氮互作显著提高了棉花的产量和水分利用效率。综合考虑产量和水分利用效率,在杂交棉花花铃期以低频高灌量和高频低灌量(日耗水量6 mm)两个水分处理在施N 300 kg/hm2时为北疆杂交棉花较适宜的灌溉策略和施氮量。 相似文献
10.
The fate of fertilizer N applied to cotton in relation to irrigation methods and N dosage in arid area 总被引：1，自引：0，他引：1
Quantitative information on the fate and efficiency of nitrogen (N) fertilizer applied to coarse textured calcareous soils in arid farming systems is scarce but, as systems intensify, is essential to support sustainable agronomic management decisions. A mesh house study was undertaken to trace the fate of N fertilizer applied to cotton (Gossypium hirsutum L. cv., Huiyuan701) growing on a reconstructed profile (0-100 cm) of a calcareous (>15% CaCO 3 ) sandy loam soil. Two irrigation methods (drip irrigation, DI; and furrow irrigation, FI) and four N application rates (0, 240, 360 and 480 kg/hm 2 , abbreviated as N 0 , N 240 , N 360 , and N 480 , respectively) were applied. 15 N-labelled urea fertilizer was applied in a split application. DI enhanced the biomass of whole plant and all parts of the plant, except for root; more fertilizer N was taken up and mostly stored in vegetative parts; N utilization efficiency (NUE) was significantly greater than in FI. N utilization efficiency (NUE) decreased from 52.59% in N 240 to 36.44% in N 480 . N residue in soil and plant N uptake increased with increased N dosage, but recovery rate decreased consistently both in DI and FI. Plant N uptake and soil N residue were greater in DI than in FI. N residue mainly stayed within 0-40 cm depth in DI but within 40-80 cm depth in FI. FI showed 17.89% of N leached out, but no N leaching occurred in DI. N recovery rate in the soil-plant system was 75.82% in DI, which was markedly greater than the 55.97% in FI. DI exhibited greater NUE, greater residual N in the soil profile and therefore greater N recovery rate than in FI; also, N distribution in soil profile shallowed in DI, resulting in a reduced risk of N leaching compared to FI; and enhanced shoot growth and reduced root growth in DI is beneficial for more economic yield formation. Compared to furrow irrigation, drip irrigation is an irrigation method where N movement favors the prevention of N from being lost in the plant-soil system and benefits a more efficient use of N. 相似文献
11.
施氮量对膜下滴灌棉花氮素吸收、积累及其产量的影响 总被引：4，自引：0，他引：4
2004年在膜下滴灌条件下,研究了施氮量0,180,270,360kg/hm2对膜下滴灌棉花氮素的吸收、累积和产量及氮肥利用率的影响。结果表明:施用氮肥可以显著提高棉花的生物和经济产量及地上部分总吸氮量,但过量施用氮肥对经济产量和生物产量增产不显著,各施氮处理氮肥利用率在27.6~33.8%之间,随施氮量的增加而降低。植株中氮素含量随生育延长而降低,氮素累积总体呈增加趋势,施氮量对棉花氮素吸收有显著影响,同一生育时期,氮素含量和累积量都随着施氮量增加而提高。本试验条件下,棉花的合理施氮量应控制在270 kg/hm2左右。 相似文献
12.
半干旱区秸秆覆盖量对土壤水分保蓄及作物水分利用效率的影响 总被引：16，自引：1，他引：15
2007～2008年在宁夏南部半干旱地区旱作春玉米播前设置了4种不同秸秆覆盖量(0、0.45、0.9、1.35万kg/hm2)处理,分析了该区秸秆覆盖量对土壤水分保蓄及水分利用效率的影响.两年定点试验表明,不同秸秆覆盖量对土壤含水量影响存在季节性、层次性差异;0.9 kg/hm2覆盖量处理,在玉米大喇叭口期以前,对保持0～40 cm土层的土壤含水量有显著效果(P< 0.05),较对照土壤水分含量提高了14.2%;秸秆覆盖量达到1.35万kg/hm 2时,土壤含水量不再显著增加.0.9～1.35万kg/hm2覆盖量处理较对照增产显著(P<0.01),幅度达16.9%;玉米水分利用效率较对照增加了4.3～5.6 kg/(mm*hm2),达到了极显著水平(P<0.01). 相似文献
13.
膜下滴灌布置方式对土壤水盐运移和产量的影响 总被引：3，自引：0，他引：3
以棉花主要根系层各生育期保持适宜土壤含水率为灌水目标,设置一膜单管四行和一膜双管四行两种毛管布置方式,以TRIME-T3管式TDR测定土壤含水率指示灌水,开展膜下滴灌大田试验,研究了干旱区膜下滴灌棉田土壤水盐运移规律及分布特征,并对不同滴灌模式下的棉花产量和灌溉水生产效率进行评价。结果表明:膜下滴灌单、双管布置棉花生育期内灌溉定额分别为390、550 mm;双管布置在10~40 cm棉花主要根系层形成适宜作物生长的淡化脱盐区,生育期内棉花主要根系层土壤含水率处于适宜的范围,灌水均匀度高,控盐效果好,棉花生长不受水盐胁迫;单管布置盐分随水分运移至湿润锋边缘至外行,棉花主要根系层有积盐的趋势,加上滴头流量大,不利于淡化脱盐区的形成。膜下滴灌毛管布置方式决定土壤水盐分布特征,进而影响植株对水分和养分的吸收,单、双管布置棉花产量分别为5 355、6 075 kg·hm~(-2),灌溉水生产效率分别为1.38、1.11 kg·m~(-3),单管布置灌溉水生产效率较高。 相似文献
14.
黄土塬区降水变化对冬小麦土壤耗水特性及水分利用效率的影响 总被引：2，自引：0，他引：2
采用人工遮雨棚和自流滴灌系统来实时人工干预降水,研究了黄土塬区不同降水条件即正常降水(CK)、降水减少1/3(R-1/3)和降水增加1/3(R+1/3)条件下,麦田0~4 m土壤水分变化、冬小麦耗水特性及WUE。结果表明:(1)降水变化改变了冬小麦对土壤水的利用和补给;降水减少,冬小麦对土壤水的利用增强,导致生育期和休闲期深层土壤含水量降低,且很难补充恢复;降水增加,冬小麦也会部分利用深层土壤水,土壤含水量在生育期呈降低趋势,在冬小麦收获后,土壤水得到补给,土壤含水量会逐渐恢复并高于前期土壤含水量。(2)冬小麦优先利用降水转化而来的土壤水,然后利用土壤前期储水;对于越冬~成熟期的总耗水量(ET)组成,R-1/3处理的冬小麦对降水和0~2 m土壤水分的利用增强,降水量(P)和0~20 m土壤贮水变化量(ΔW0-2 m)各自约占ET的40%;R+1/3处理P占ET的比例约是ΔW0~2 m的1倍多;CK处理P占ET的比例比ΔW0~2 m高15%左右;降水减少,降水占耗水量的比例降低,0~2 m土壤水占耗水量比例增加;降水增加,则有相反的结果。(3)降水减少,WUEbio(基于生物量的WUE)相对于CK处理降低了1.3%,但产量下降程度(7.1%)小于耗水下降程度(14.2%),WUEgrain(基于籽粒产量的WUE)反而增加;降水增加,相对于CK处理生物量减少5.3%而籽粒产量增加4.5%,但水分的消耗增加了11.4%,WUEbio和WUEgrain均降低。总之,降水变化改变了冬小麦对土壤水的利用、土壤水的补给、冬小麦的耗水组成以及生物量和产量的平衡,最终影响冬小麦WUE。 相似文献
15.
Water and nitrogen(N) are generally two of the most important factors in determining the crop productivity. Proper water and N managements are prerequisites for agriculture sustainable development in arid areas. Field experiments were conducted to study the responses of water productivity for crop yield(WP_(Y-ET)) and final biomass(WP_(B-ET)) of film-mulched hybrid maize seed production to different irrigation and N treatments in the Hexi Corridor, Northwest China during April to September in 2013 and also during April to September in 2014. Three irrigation levels(70%–65%, 60%–55%, and 50%–45% of the field capacity) combined with three N rates(500, 400, and 300 kg N/hm~2) were tested in 2013. The N treatments were adjusted to 500, 300, and 100 kg N/hm~2 in 2014. Results showed that the responses of WP_(Y-ET) and WP_(B-ET) to different irrigation amounts were different. WP_(Y-ET) was significantly reduced by lowering irrigation amounts while WP_(B-ET) stayed relatively insensitive to irrigation amounts. However, WP_(Y-ET) and WP_(B-ET) behaved consistently when subjected to different N treatments. There was a slight effect of reducing N input from 500 to 300 kg/hm~2 on the WP_(Y-ET) and WP_(B-ET), however, when reducing N input to 100 kg/hm~2, the values of WP_(Y-ET) and WP_(B-ET) were significantly reduced. Water is the primary factor and N is the secondary factor in determining both yield(Y) and final biomass(B). Partial factor productivity from applied N(PFP_N) was the maximum under the higher irrigation level and in lower N rate(100–300 kg N/hm~2) in both years(2013 and 2014). Lowering the irrigation amount significantly reduced evapotranspiration(ET), but ET did not vary with different N rates(100–500 kg N/hm~2). Both Y and B had robust linear relationships with ET, but the correlation between B and ET(R~2=0.8588) was much better than that between Y and ET(R~2=0.6062). When ET increased, WP_(Y-ET) linearly increased and WP_(B-ET) decreased. Taking the indices of Y, B, WP_(Y-ET), WP_(B-ET) and PFP_N into account, a higher irrigation level(70%–65% of the field capacity) and a lower N rate(100–300 kg N/hm~2) are recommended to be a proper irrigation and N application strategy for plastic film-mulched hybrid maize seed production in arid Northwest China. 相似文献
16.
通过大田试验分析了全膜覆土穴播、垄作沟灌及平作条播栽培模式对大麦的土壤水分时空动态、产量及其水分利用效率的影响。结果表明,全膜穴播处理极有利于大麦的早期出苗及营养生长。但垄作沟灌栽培处理有利于促进大麦生殖生长。全膜穴播处理产量较垄作沟灌和平作条播处理分别增产10.9%和15.31%,并且WUE分别高10.69%和11.09%,说明全膜穴播栽培处理增加了大麦土壤的可利用水分,提高了产量和WUE。 相似文献
17.
不同穴播种植方式与平衡施肥对旱地春小麦产量及水分利用效率的影响 总被引：12，自引：0，他引：12
采用田间试验方法,研究了不同穴播种植方式与平衡施肥对旱地春小麦产量及水分利用效率的影响。结果表明,4种穴播种植方式中,全膜覆土穴播种植方式有利于小麦碳水化合物的合成,增加了小麦干物质积累量,实施N、P、K平衡施肥后干物质积累量增加效果明显;该种植方式下各施肥处理比全膜小垄沟覆土穴播、全膜不覆土穴播和露地穴播小麦产量分别增加3.7%～6.7%、9.4%～10.3%、30.7%～35.4%;该种植方式下,N、P2O5和K2O的用量分别为180 kg/hm2、120 kg/hm2、90 kg/hm2时(Z0F1处理),小麦产量最高,达到4 034 kg/hm2;该方式的小麦水分利用效率明显高于露地穴播,在相同施肥水平下,前者小麦水分利用效率比后者显著提高33.7%～48.3%。表明春小麦在全膜覆土穴播栽培技术条件下,平衡施肥可显著提高小麦籽粒产量和水分利用效率。 相似文献
18.
生育期水分调控对河西地区滴灌春小麦生长和水分利用的影响 总被引：2，自引：0，他引：2
为探索干旱地区有利于春小麦生长和提高产量的大田滴灌灌水模式,以春小麦永良4号为试验材料,在不同生育期(苗期~分蘖,拔节~孕穗,抽穗~开花,灌浆~成熟)设置5个土壤水分下限W1(55%、60%、55%、50%),W2(60%、65%、60%、55%),W3(65%、70%、65%、60%),W4(70%、75%、70%、65%)和充分灌溉(CK)(75%、80%、75%、70%),研究了不同生育期土壤水分调控对河西地区滴灌春小麦生长、产量和水分利用效率的影响。结果表明:一定施肥水平下,随着土壤水分下限的提高,各处理株高、叶面积指数均不断增大,在成熟期充分灌溉(CK)处理分别比W4处理高2.19%和7.93%;不同水分下限处理条件下,春小麦干物质的总积累量和成熟期干物质向籽粒的分配量均为W4处理最大,比CK分别显著高5.63%和17.14%;各处理春小麦产量和水分利用效率随着土壤水分下限的增加均呈先增加后减小的变化趋势,其中W4处理的水分利用效率比W3处理降低2.82%,但其产量分别比W3、CK处理增加7.53%和4.07%。从节水增产的角度考虑,W4处理可作为基于本试验条件下较适宜的水分处理。 相似文献
19.
土壤水分调控对南疆滴灌棉花生长、品质及水分利用的影响 总被引：1，自引：0，他引：1
针对南疆地区水资源短缺、棉田水分利用效率低等问题,研究膜下滴灌条件下土壤水分下限调控对棉花生长、产量、品质和水分利用效率的影响。以棉花品种新陆中66号为材料,以田间持水量(FC)为土壤水分上限,棉花生育期设置85%FC(T1)、75%FC(T2)、65%FC(T3)、55%FC(T4)和45%FC(T5)5个土壤水分下限来调控土壤水分。结果表明：土壤水分下限的提升对株高和生物量有明显的促进作用, 土壤水分下限从 45%FC增至85%FC,棉花株高和生物量分别增加了25.80%和25.38%;随着土壤水分下限的降低,灌溉定额减少,T1处理灌溉定额最大（378 mm）,T2、T3、T4、T5处理与之相比分别节水11.64%、33.07%、33.95%、46.83%;随着土壤水分下限的提升,棉花产量逐渐增大,但土壤水分下限过高,棉花单株有效铃数降低,产量增加不再明显,水分利用效率较低;土壤水分下限为75%FC时棉花单株有效铃数、单铃重增加,产量和水分利用效率分别达到7 146.4 kg·hm-2和1.40 kg·m-3;土壤水分调控对棉花纤维品质有显著影响,土壤水分下限越低,马克隆值越大,成熟度指数越高,断裂比强度和断裂伸长率减少,采用主成分分析法得出T2为棉花品质综合较优的处理。因此,建议在膜下滴灌方式下南疆盐碱地区棉花土壤水分下限控制在75%FC为宜,非生育期进行冬灌淋盐,冬灌定额为300 mm,生育期灌溉定额为334 mm,整个生育期灌水12次,灌水周期为8 d。 相似文献
20.
闫映宇 《干旱地区农业研究》2016,34(4):18-24
以2007—2012年塔里木灌区膜下滴灌田间灌溉试验数据为基础,采用最小二乘法原理,拟合了棉花的水分生产函数模型,分析并计算了棉花最高产量灌溉定额、最佳效益灌溉定额、高效用水灌溉定额,揭示了棉花的水分效应及需水规律。结果表明:塔里木灌区膜下滴灌棉花需水临界期是花铃期和蕾期;产量与耗水量、灌水量均呈良好的二次抛物线关系;合理灌溉定额为3 091~3 464 m~3·hm~(-2),最高产量灌溉定额为3 464 m~3·hm~(-2),高效用水灌溉定额为3 091 m~3·hm~(-2);水资源投入的最佳效益点并非水分利用效率最高点和最高产量点,而是存在于3091~3 464 m~3·hm~(-2)区间;当边际效益等于边际成本时,净收益最大,为24 333.1元·hm~(-2),每立方灌水量净收益7.23元·hm~(-2);现状条件下最佳效益灌溉定额为3 459 m~3·hm~(-2),产量为6 360.7 kg·hm~(-2),与最高产量6 360.8kg·hm~(-2)基本相同,但比最高产量节水5 m~3·hm~(-2),每立方灌水净收益增加0.21元·hm~(-2),水分利用效率提高0.003 kg·m-3。 相似文献