【作者】 马红菊；

【导师】 文宏达； 张立峰；

【作者基本信息】 河北农业大学 ， 土壤学， 2007， 硕士

【摘要】 降雨作为冀西北高原农业生产唯一的水分补给，其高效利用关系到农业生产经济效益的提高。在小南瓜正逐步转变为河北坝上地区农业生产的优势作物过程中，提高小南瓜产值以利于农民增收成为一个重大任务。试验于2006年在河北农业大学张北试验站进行。选择占全区耕地总面积65％以上的坡梁地砂质栗钙土为研究背景，针对冀西北高原栗钙土农田土层浅薄土壤贫瘠、作物生育期内降水分布不均以致出现阶段性干旱等障碍因素，以小南瓜为供试材料，研究开沟覆膜对降水富集叠加以及对于土壤水分时空分布规律的影响；明确垄沟系统下不同补灌处理对小南瓜产量的影响以及补水后小南瓜水分、养分吸收效应和补水效益；探讨氮肥追施时期对于小南瓜水分及经济产量的影响。结果表明：1．在小南瓜不同生育期补灌不同水量比未补水处理均有不同程度的增产，增产率为4.7％～28.0％。在小南瓜开花座果期补一次水，补水量为15.0mm时，耗水量高于未补水处理，小南瓜经济产量达到处理的最高产量水平，与未补水处理相比差异显著，经济产量相对增加2331.3kg·hm^-2，为其126.8％；水分利用效率（鲜）提高16％，由补水产生的净收益相对于未补水处理增加2153.4yuan·hm^-2，每补单方水效益达57.4元。采用滴灌方式补水，相对于点灌来说，也可以增加小南瓜经济产量，等量补水条件下，可增产742.1kg·hm^-2，使得补水效率更高。补水对于小南瓜根系养分吸收有一定的影响。补水后，氮钾的可移动性增强，由于是在开花座果期和果实膨大期进行补水，此期正处于营养生长和生殖生长的转换期，有利于提高小南瓜经济产量。2．覆膜可使单次降水小于5mm雨水得以利用。开沟覆膜与未覆膜处理相比，沟中和沟侧土壤水分都得到了提高。在监测的46天内，覆膜下，0～50cm土体水贮量沟中比未覆膜增加72.0mm，沟侧增加37.3mm，而垄中水分无明显差别。同时，监测还发现，覆膜条件下，有利于水分入渗深度的增加，较强降水下可能产生渗漏。另外，未覆膜小南瓜在8月21日时叶片出现萎蔫现象，覆膜下未出现此种现象，监测结果表明，萎蔫时0～80cm土体水贮量比未萎蔫时（覆膜下）低8.97mm，且差异主要表现在0～60cm土层。3．在小南瓜伸蔓期和果实膨大期全追及分次追施氮肥，均可显著提高小南瓜经济产量和水分利用效率。其中，伸蔓期追施氮肥使经济产量和水分利用效率达最高值，分别比无追肥处理增加87.3％和69.3％。更多还原

【Abstract】 As the only water supplement for agriculture, high efficiency of rainfall use was veryimportant in northwest plateau of Hebei province, it related to the enhancement ofeconomic benefit of agricultural production. Improving pumpkin value to increasepeasents’ income was a momentous task when pumpkin was determined as dominant cropof northwest plateau of Hebei province. The research was conducted in Zhangbeiexperimental station of Hebei Agricultural University in 2006. This paper was based on thesandy chestnut soil, which was accounted for 65% of land in northwest plateau of Hebeiprovince, and small pumpkin was choosed as experimental material. With plastic filmmulching over furrow, spatial distribution and temporal change of soil water that rainfallconversed to were studied. Yield and water response of pumpkin after spatial andtemporal supply of harvested rainwater were researched. And the effects of different stageof supplemental nitrogen application on economic yield and soil water of pumpkin werecompleted. The results showed that:1. Supplied water during bloom and fruit period, when the amount was 15.0mm, althoughwater consumption was higher than the treatment, of non-supplying water （ck）, theeconomic yield and water use efficiency （WUE） was at the highest level, compared tock, the economic yield enhanced 2331.3kg·hm⁾-2), accounted for 126.8%; and the WUE,economic value enhanced 16% and 2153.4yuan.hm^-2 respectively than the treatmentnon-supplying water. The output value was 57.4yuan.m^-3.Compared to hole irrigation, economic yield could be enhanced 742.1kg·hm^-2 by dropirrigation with the equal amount, efficiency of supplying water was enhanced.2. Rainfall＜5mm can be utilized by plastic film mulching over furrow. Between plasticfilm mulching over furrow and non-mulching group, Soil water storage can be improvedby plastic film mulching over furrow, 0～50cm soil water storage of furrow and furrow sideenhanced 72.0mm and 37.3mm separately by plastic film mulching over furrow duringmonitoring days, and on the ridge, there was no significant difference between the twotreatments. Meanwhile, it was helpful for soil water infiltration, percolation of soil watercan be possible.Otherwise, the leaves of pumpkin started wilting when there was no film mulching on21th, August. Here, 0～80cm soil water storage was 8.97mm lower than that film mulchingover furrow, and the major differences were present to 0～60cm soil water amount. When the film mulched the pumpkin over furrow, the leaes of pumpkin didn’t wilt yet..3. The economic yield and WUE were enhanced significantly after supplemental nitrogenfertilizer dressing in different growth stages. Of which, vine-extension stage was the beststage for supplemental nitrogen fertilizer dressing, the economic yield and WUE wereenhanced 87.3% and 69.3% respectively than that of non-dressing treatment.更多还原