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111.
摘要:为了满足朝阳地区农业生产的需要,设计了一种铺膜播种机,可以一次性完成铺设滴灌带、铺膜、空中四线路立体覆土、膜上沟内播种和镇压等作业,经田间试验测试,各项性能指标达到了《铺膜播种机》(JB2T7732-2006 )行业标准的要求。  相似文献   
112.
沙漠绿洲区不同灌水方式条件下玉米灌溉制度研究   总被引:8,自引:1,他引:8  
在石羊河流域干旱缺水的民勤县连续进行了 4年田间试验 ,研究了大田地膜玉米畦灌、常规沟灌、交替隔沟灌溉和宽垄沟灌 4种灌水方式下的灌溉定额及其对产量和水分利用的影响 ,拟定了不同灌水方式下的灌溉制度 ,得出交替隔沟灌溉方式下灌水 7次 ,次灌水定额为 30 0 m3/hm2 ,灌水时间为拔节期、大喇叭口期、抽雄期、抽穗期、灌浆始、灌浆中、乳熟期的灌溉制度为该地区推荐采用的最优方案。  相似文献   
113.
设置交替隔沟灌、常规沟灌和固定隔沟灌方式,施氮量和灌水量采用二次通用旋转组合设计进行试验,研究水、氮调控对沟灌棉花产量、水分利用效率的影响.结果表明:棉花产量与施氮量在56.2~95.2kg·hmˉ2范围内呈显著正相关,与灌水量在37.52~160.00mm范围内呈显著正相关.相同水、氮处理下交替隔沟灌与常规沟灌相比棉...  相似文献   
114.
保护性耕作改变了传统农业耕作方式,已成为旱区农业可持续发展的有效途径,是当前农机化推广的重点技术之一。介绍保护性耕作的技术内容和试验示范效果,分析保护性耕作推广中存在的问题,并提出相应的解决对策,为大规模推广保护性耕作提供经验。  相似文献   
115.
针对西南丘陵地区保护性耕作模式下小麦免耕播种机尖角型开沟器易缠草,堵塞,使用寿命短等问题,设计了圆弧刃口型开沟器。该文建立了圆弧刃口型开沟器的几何模型,采用离散元法对圆弧刃口型开沟器的工作阻力进行了分析。试验结果表明:平均开沟宽度为40 mm,开沟深度偏差为5 mm,玉米根茬的切断率超过86%,土壤扰动为18%~22%。圆弧刃口型开沟器提高了播种机的通过性,开沟破茬效果好,能够满足西南丘陵地区小麦免耕播种的开沟要求。  相似文献   
116.
黑龙江农垦九三分局所辖农场由冲刷沟造成的土壤侵蚀极其严重,水土流失面积占总面积的35.94%。通过对冲刷沟成因及冲刷沟引起土壤侵蚀类型的分析,将冲刷沟分成3种类型,分别为幼年期冲刷沟、中年期冲刷沟及老年期冲刷沟,并提出相应的治理原则及措施。  相似文献   
117.
为了探讨辽宁中部地区大豆节水优质灌溉模式,在有滑动遮雨棚的测坑中进行田间试验,研究了常规沟灌、固定沟灌和交替沟灌3种灌溉模式对大豆的性状、产量及品质的影响。研究结果表明,交替沟灌比常规沟灌、固定沟灌更能促进大豆的根和茎粗的生长;其水分利用效率比常规沟灌和固定沟灌分别提高了25.4%和13.3%,产量提高了13.0%和7...  相似文献   
118.
In the northwestern Loess Plateau of China, low precipitation results in poor crop yields, with a great fluctuation from year to year. The adoption of gravel-sand mulching has shown improvements in the growth of crops such as watermelon. The ridge and furrow rainwater harvest system (RFRHS) has been shown as an easy and efficient way to collect rainwater. A field experiment was conducted from 2007 to 2009 at Gaolan, Lanzhou, Gansu, China, to measure the effects of RFRHS, plastic mulch and gravel-sand mulch combinations on soil temperature, evapotranspiration (ET), water use efficiency (WUE) and watermelon yield. There were eight treatments: (1) flat gravel-sand mulched field, (2) RFRHS with a sand mulched furrow, entire plastic mulch and the ratio 1:1 of ridge and furrow, (3) RFRHS with a sand mulched furrow, entire plastic mulch and the ratio 4:3 of ridge and furrow, (4) RFRHS with a sand mulched furrow, entire plastic mulch and the ratio 5:3 of ridge and furrow, (5) RFRHS with a sand and plastic mulched furrow, bare ridge and the ratio 4:3 of ridge and furrow, (6) RFRHS with an entire plastic mulch and the ratio 4:3 of ridge and furrow, (7) conventional ridge planting with a plastic mulched ridge, and (8) flat gravel-sand mulched field plus 23 mm supplementary irrigation. Soil temperature for RFRHS with a gravel-sand plus plastic mulched furrow was slightly lower than that of flat gravel-sand mulch. The RFRHS caused a significant increase in watermelon yield and WUE. The increase in watermelon yield and WUE was greatly influenced by the ratio of ridge and furrow when RFRHS was combined with gravel-sand mulch. Watermelon yield was highest for the 1:1 ratio, and WUE was highest for the 5:3 and 1:1 ratios of ridge:furrow, and these were significantly greater than that of flat gravel-sand mulch, without or with irrigation. The use of ridge with plastic film mulch increased the beneficial effect of RFRHS on yield. The watermelon yield and WUE for non-plastic-mulched ridge were even lower than that of flat gravel-sand mulch. In summary, the findings suggest that RFRHS with gravel-sand mulched furrow plus plastic film mulch, and 1:1 ratio of ridge:furrow, would facilitate the use of limited rainfall most efficiently in improving watermelon yield, by reducing ET and increasing WUE in this semiarid region.  相似文献   
119.
Emergence of cotton (Gossypium hirsutum L.) under flatland mechanized planting system with crust-forming soil and saline soil and irrigation water can be suboptimal in central Iran. A field experiment was conducted to determine furrow opener type and crust-breaking method effects on cotton emergence on a silty clay soil (Calcic Cambisols). The effects of five planters (equipped with runner, single- and double-disk type openers) and five crust-breaking methods (using rolling cultivator, rolling-type crust breaker, spike-tooth, chain-type harrows and no crust-breaking) on the seedling emergence were studied. The results showed that planter type significantly affected cotton seedling emergence. In non-crust-breaking method, the best emergence was produced with the double-disk opener planter that created crack lines along the seed rows. This phenomenon was not observed with the runner-type opener planter. However, some crack lines were observed on the outside edges of its smooth-crown zero-pressure press wheels tires, which resulted in large clod formation after crust-breaking and had therefore negative effect on seedling emergence. Crust-breaking had negative effect on final emergence for double-disk planter due to filling the crack lines with loosened soil. Crust-breaking improved emergence percentages for runner opener planters, when the depth of penetration of the crust breaker teeth was shallow. The conclusion is that irrigated cotton emergence on crust-forming soils in a flatland planting system might significantly be improved by selecting a double-disk planter with zero-pressure press wheel tires without any crust-breaking operation under the soil and climate of central Iran.  相似文献   
120.
为了阐明不同沟向与沟灌方式下作物根区土壤温度的变化规律,通过垄作玉米田不同点位处的根区地温观测,研究了南北沟向和东西沟向下交替隔沟灌溉(AFI)和常规沟灌(CFI)田的地温变化。结果表明,东西沟向时AFI在湿沟、垄位和干沟处0~20cm土温分别高于南北沟向0~4.60、0~5.37、0~6.57℃;同一沟向条件下,AFI的平均土温比CFI提高了0.02~7.00℃,且AFI在非灌水区域的土温比灌水区域高0.23~6.20℃。东西沟向AFI的作物根区土温最高,提高了根区土壤热能,以其通过栽培方式或灌溉方式的改变调节田间光热环境以适应不同作物的生长需求。  相似文献   
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