【作者】 齐广平；

【导师】 张恩和；

【作者基本信息】 甘肃农业大学 ， 作物栽培学与耕作学， 2008， 博士

【摘要】 试验于2005～2006年在甘肃农业大学农业生态工程试验站进行,玉米和番茄作为供试作物,通过管栽和大田试验,研究了在膜下滴灌条件下不同灌溉定额[玉米:高灌溉(4875 m3.hm-2)、中等灌溉(4275 m3.hm-2)、低灌溉(3750 m3.hm-2);番茄:高灌溉(5426 m3.hm-2)、中等灌溉(4419 m3.hm-2)、低灌溉(3700 m3.hm-2)]和不同施盐水平[玉米:高盐(0.998%)、中盐(0.978%)、低盐(0.958%);番茄土壤含盐量为0.958%]对地上和地下部分生长发育的影响,水盐运移的基本规律以及水盐运移对作物冠层发育和根系分布等影响,主要结论如下:1.覆膜滴灌可以减少蒸发,抑制盐分上移,同时对根系形成了一个良好的水盐环境。滴灌水对表层土壤具有洗盐作用,在根系主要分布区(0-40cm)形成淡化脱盐区。2.土壤水分分布主要受滴灌量、蒸散、根系吸水等作用的影响。覆膜抑制了地表土壤水分蒸发,同时作物根系生长发育状况和分布规律主要受土壤水分和肥力状况的影响,特别是深层根系。3.当施盐量相同,不同灌溉处理下,在玉米苗期,土壤水分峰值(19.76%)出现在60-100cm土层;在玉米拔节期,土壤水分峰值(11.42%)出现在40-60 cm土层。当灌溉量相同,不同施盐处理下,在玉米各生育期,土壤水分峰值(19.36%)出现在40-60cm土层。结合玉米产量结果,在土壤含盐量0.998%以下的盐碱地均可进行玉米生产,在该试验条件下,灌溉量(4275 m3.hm-2)为玉米生产的适宜灌溉量。4.当施盐量相同,不同灌溉处理下,在番茄各生育期,高灌溉土壤水分峰值(20.47%)、中灌溉土壤水分峰值(21.29%)与低灌溉土壤水分峰值(21.07%)分别出现在60-100cm、40-60cm与60-100cm土层;在番茄苗期,土壤水分峰值(21.06%)出现在60-100cm土层;在开花坐果期,土壤水分峰值(24.04%)出现在20-40cm土层;在水平方向,土壤含水量随距滴头距离的增大而减小,在距滴头55 cm处达到最小值(9.58%)。结合番茄产量结果,在土壤含盐量0.958%以下的盐碱地均可进行番茄生产,在该试验条件下,灌溉量(4419 m3.hm-2)为番茄生产的适宜灌溉量。5.在同一盐基水平、不同灌溉量下,Cl-、SO42-、Na+随灌溉量的增大向土壤深层淋溶越深。在玉米苗期,Cl-峰值(0.386 g/kg)主要出现在60-100cm土层,SO42-峰值(1.332g/kg)主要出现在40-60cm土层;在玉米拔节期,Cl-和SO42-峰值主要出现在40-60cm土层;在玉米各生育时期,Na+峰值(4.21 g/kg)主要出现在20-40cm土层。当灌溉量相同,施盐量不同时,在玉米苗期,Cl-峰值(0.389 g/kg)、SO42-峰值(0.517 g/kg)和Na+峰值(1.766 g/kg)均主要出现在60-100cm土层;在玉米拔节期,Cl-峰值(0.863 g/kg)、SO42-峰值(0.833 g/kg)和Na+峰值(1.766 g/kg)均主要出现在40-60cm土层。中等灌溉处理盐淋溶深度大于高灌溉处理和低灌溉处理,且获得较高的产量,由于玉米根系主要分布在0-40cm土层,中等灌溉处理盐离子主要分布在40cm以下土层,减轻了盐分对玉米根系的毒害作用,导致玉米产量提高。6.在同一盐基水平、不同灌溉量下, Cl-峰值(0.199 g/kg)主要出现在40-60cm土层,SO42-峰值(1.22g/kg)和Ca2+(0.96g/kg)峰值主要出现在60-100cm土层。在番茄苗期,Cl-、SO42-、Ca2+在60cm左右土层的含量最高;在番茄开花坐果期,Cl-、SO42-峰值主要出现在40-60cm土层。中等灌溉处理减轻了盐分对番茄根系的毒害作用,导致番茄的产量提高。7.研究发现,玉米和番茄的根系随土壤深度的增加而减少,高灌溉处理的作物根系分布土层较低灌溉浅。约有85%玉米根干重分布在0-60cm土层,根长和根干重在玉米抽雄期达到最大值;约有75%番茄根干重分布在0-20cm土层,番茄根长和根干重在结果初期达到最大值。玉米和番茄根系消弱系数也说明了这种分布特征。8.玉米与番茄地上生物量呈“S”曲线生长,它们地上生物量与生长时期呈三次曲线变化。番茄果实产量呈“单峰型”曲线生长,番茄果实产量与生长时期呈三次曲线变化。9.在西北半干旱地区膜下滴灌是首选的灌溉方式。膜下滴灌作物的水分效率大于常规沟灌,高灌溉处理、中等灌溉处理与低灌溉处理的水分效率比常规沟灌分别提高了69.34%、141.27%与144.81%。通过膜下滴灌与常规沟灌的经济评价,结果表明,膜下滴灌的各项评价指标均高于常规沟灌。中等灌溉处理(4419 m3.hm-2)的各项评价指标均高于高灌溉处理和低灌溉处理。因此,在番茄生产中,当盐碱地土壤含盐量为0.958%以下,选用膜下滴灌中等灌溉量可以获得较高产量。更多还原

【Abstract】 The study was conducted to determine the development of above-ground and under-ground biomass, soil water and salt transport regularity, effect of soil water and salt transport regularity on development of above-ground biomass and root distribution in drip irrigation under mulch on saline-alkaline land at Agriculture Ecology Engineering Station of Gansu Agricultural University during crops grow season of 2005 and 2006, different irrigation treatments (maize: high irrigation (4875 m3/hm2)、medium irrigation (4275 m3/hm2)、low irrigation (3750 m3/hm2);cherry tomato: high irrigation (5426 m3/hm2)、medium irrigation (4419 m3/hm2)、low irrigation(3700 m3/hm2) and different salt supply levels (maize: high salt supply (0.998%)、medium salt supply (0.978%)、low salt supply(0.958%);the same salt level (0.958% ) was supplied for cherry tomato) were employed in column and field experiments, maize and cherry tomato as an indicator crops. The results are followed:1. Evaporation and salt upper movement were reduced, formed 20– 40 cm light salinity root area, which is good for crop growth, indicated that drip irrigation under mulch had a effective of washing desalinization, especial on saline-alkaline land.2. Soil water moisture was affected by amount of drip irrigation, evaporation and water absorption of root. Mulch reduced evaporation of surface soil layer, the growth state and distribution of root was influenced by soil water content and soil fertilization, the affect of soil water content on deep root growth was evidence.3.Salt supply level was same, in different irrigation treatments, the highest soil moisture level (19.76%) was reached 60-100 cm soil layer at maize emerging stage; at maize jointing stage, the highest soil moisture level (11.42%) was reached 40-600 cm soil layer. Irrigation was same, in different salt supply levels treatments, the highest soil moisture level (19.36%) was reached 40-60 cm soil layer at maize different growth stages.The maize experiment indicated that maize production can be obtained on saline-alkaline land with soil salt level under 0.998%, amount of irrigation (4275 m3/hm2) was optimum management for maize production in similar experimental conditions.4. Salt supply level was same, in different irrigation treatments, the highest soil moisture level was reached 60-100 cm、40-60cm and 60-100cm soil layer under high irrigation, medium irrigation and low irrigation treatments respectively, there values were at 20.47%, 21.29% and 20.07% related to corresponding irrigation treatments, at different cherry tomato growth stages. The highest soil moisture level (21.06%) was reached 60-100 cm soil layer at cherry tomato emerging stage; at flowering and fruit-bearing stage, the highest soil moisture level (24.04%) was reached 20-40 cm soil layer. In horizontal direction, the soil water content was decreased with distance from drip sprinkler, soil moisture (9.58%) in 55 cm was reached the highest level. The cherry tomato experiment indicated that cherry tomato production can be obtained on saline-alkaline land with soil salt level under 0.958%, amount of irrigation (4419 m3/hm2) was optimum management for cherry tomato in similar experimental conditions.5. Salt supply level was same and irrigation was different, the leaching depth of Cl-, SO42-, and Na+ were increased with irrigation. At maize emerging stage, the highest Cl- content (0.386 g./kg ) was reached 60-100 cm soil layer, the highest SO42- content (1.332 g./kg ) was reached 40-60cm cm soil layer; at maize jointing stage, the highest level of Cl- content and SO42- content was reached 40-60cm cm soil layer. At different maize growth stages, the highest Na+ content (4.21 g./kg ) was reached 20-40cm soil layer. Irrigation was same and salt supply level was different, at maize emerging stage, the highest levels of Cl- content (0.389 g./kg ), SO42-content (0.517 g./kg ), Na+ content (1.766 g./kg ) was reached 60-100 cm soil layer; at maize jointing stage, the highest levels of Cl- content (0.863 g/kg)、SO42- content (0.833 g/kg) and Na+ content (1.766 g/kg) were reached at 40-60cm soil layer. Medium irrigation treatment has higher effect of salt leaching than high irrigation treatment and low irrigation treatment. It indicated that main roof grow within 40 cm soil layer, salt leaching below 40 cm soil layer after medium irrigation, medium irrigation treatment can reduce salt toxicity to plant root, leading higher maize production.6. Salt supply level was same and irrigation was different, the highest Cl- content (0.199 g./kg ) was reached 40-60 cm soil layer, the highest SO42- content (1.22 g./kg ) and the highest Ca2+ content (0.96 g./kg ) was reached 60-100cm cm soil layer. At cherry tomato emerging stage, the highest levels of Cl- content, SO42- content and Ca2+ was reached about 60cm soil layer; at flowering and fruit-bearing stage, the highest levels of Cl- content and SO42- content was reached 40-60cm soil layer. Medium irrigation treatment can reduce salt toxicity to plant root, leading higher cherry tomato production.7. The experiment was showed the root of maize and cherry tomato was decreased with amount of irrigation, the depth of root distribution in high irrigation was shallower than in low irrigation. About 85 % of dry maize root weight was distributed within 0-60cm soil layer, the root length and dry root weight was highest at maize heeding stage; about 75 % of dry cherry tomato root weight was distributed within 0-20cm soil layer, the root length and dry root weight was highest at cherry tomato flowering and fruit-bearing stage. The root extinction coefficient was also showed similar results. 8. The grow tendency of canopy biomass of maize and cherry tomato with growth date is“S”curve, the equation is cubic curve. The grow tendency of fruit yield of cherry tomato biomass with growth date is“Unimodal type”curve, the equation is cubic curve.9. Drip irrigation under mulch was best management in semiarid area of Northwest of China. Drip irrigation under mulch had higher water use efficiency (WUE) than traditional furrow irrigation, the more WUE increase was 69.34%, 141.27% and 144.81 in high irrigation treatment, medium irrigation treatment and low irrigation treatment than in traditional furrow irrigation, respectively. After economical evaluation, the medium irrigation treatment (4419 m3/hm2) had higher evaluated parameters than high irrigation treatment and low irrigation treatment. Drip irrigation under mulch was best choice on saline-alkaline land with salt under 0.958%, medium irrigation treatment obtained the highest fruit yield for cherry tomato in semiarid area of Northwest of China.更多还原