陕北渭北粮食开发的潜力与途径

论述了陕北渭北粮食开发的重要意义,定量分析了陕北渭北粮食播种面积、粮食单位面积产量和粮食总产量增长潜力。结果表明,在现有栽培技术条件下,“二北”粮食总产量最高可望达到７８．５０亿ｋｇ,较“八五”期间净增产４３．６７亿ｋｇ．最后分析了潜力开发的可能途径与应具备的条件。     

小麦品种产量与产量因素通径分析

通过对９４个不同品种小麦在渭北地区干旱条件下的试验数据,分类建立小麦产量与产量因素的回归关系,并做了通径分析。结果表明,在分类小麦的关系中,穗粒数对产量的总影响和直接影响都最大。     

旱作农田保护性耕作-液膜-施肥综合技术研究

在山西寿阳地区旱作春玉米保护性耕作试验基础上,增加液态地膜覆盖处理和肥料用量处理,研究不同耕作-液膜-施肥配合措施对土壤温度、土壤水分利用、作物苗生长和产量的影响。结果表明：与传统耕作比较,采用液态地膜覆盖后,免耕土壤苗期地表温度提高0.5~2℃,春玉米出苗数提高18%以上;玉米增产约5%;0～200 cm土壤水分增加21 mm;ET增加12 mm,为改善旱作保护性耕作-液膜-施肥管理综合技术效果提供依据。     

机械化整秆覆盖膜侧沟播保护性耕作技术的试验研究

中国黄土高原地区由于干旱、无霜期短而严重影响春玉米产量,该文研究应用整秆覆盖免耕膜侧播种的耕作模式,在冬闲期采用机械将玉米秸秆整秆压倒覆盖免耕,在种植期带状起垄覆膜,膜侧播种,行间秸秆覆盖,集储水、保墒、增高地温于一体。结果表明,该技术与传统的露地深翻模式相比,具有明显的储水、保墒、增高地温和提高玉米产量的效果。     

冀西北旱坡地南瓜田间沟垄集雨种植模式研究

在怀安县前所堡旱作示范区以南瓜为试材,采用窄土垄沟、宽土垄沟、窄膜垄沟、宽膜垄沟4种不同沟垄处理方式,常规平作为对照,研究不同的沟垄措施对南瓜地土壤水分含量、水分利用及产量的影响.结果表明:沟垄栽培可使水分聚集于种植沟中较小有效栽培面积中,改善土壤水分分布状况,不同处理间效应大小依次为:宽膜垄沟＞窄膜垄沟＞宽土垄沟＞窄土垄沟＞平作,且覆膜效应大于垄的宽窄效应;沟垄处理对土壤水分在表层影响大,在较深土层影响小.沟垄处理均可提高水分利用效率,其中土垄与平作差异不明显,而膜垄水分利用率宽膜垄沟(40.85 kg·hm-2·mm-1)、窄膜垄沟(39.03 kg·hm-2·mm-1)均显著高于平作(30.27 kg· hm-2· mm-1)(P＜0.05),宽垄比窄垄水分利用率高,但差异不显著.不同沟垄处理对南瓜的产量影响较大,产量增加4.23％～32.39％,增产效益176.2～1 210.4元·hm-2,两膜垄组南瓜产量与对照平作差异显著(P＜0.01),尤以宽膜垄沟增产效益为最高.综上所述,宽膜垄沟的栽培方式对南瓜水分利用和增产增效作用显著,是目前坡耕旱地南瓜生产中较为理想的田间沟垄微型集雨种植模式.     

Response of yield increase for dryland winter wheat to tillage practice during summer fallow and sowing method in the Loess Plateau of China

Soil moisture is the most critical limiting factor impacting yields of dryland winter wheat(Triticum aestivum L.) and it is strongly affected by tillage practice and sowing methods. This study was to assess the link between sowing method and tillage practice during summer fallow and their subsequent effect on soil moisture and grain yield. Furthermore, we sought to identify a more appropriate farming management practice for winter wheat production in Loess Plateau region of China. The experiment was conducted from 2011 to 2013, using a two-factor split plot design, including subsoiling(SS) or no tillage(NT) during summer fallow for main plots, and conventional drill sowing(DS) or plastic film drill sowing(FM) for subplots. Results showed that the maximum soil water storage(SWS) was under SS×FM treatment with values of 649.1 mm(2011–2012) and 499.4 mm(2012–2013). The SWS during the 2011–2012 growing season were 149.7 mm higher than that in the 2012–2013 growing season. And adoption of SS×FM significantly increased precipitation use efficiency(PUE) and water use efficiency(WUE) compared to other treatments for both seasons. Moreover, adoption of SS×FM significantly increased yield by 13.1, 14.4, 47.3% and 25.9, 39.1, 35.7% than other three treatments during the two growing seasons, respectively. In summary, combining subsoiling during summer fallow with plastic film drill sowing(SS×FM) increased SWS at sowing and effectively improved WUE, thus representing a feasible technology to improve grain yield of dryland winter wheat in the Loess Plateau of China.     

渭北旱塬不同耕作措施对土壤养分分布及作物产量的影响

基于8年(2007—2015)定位试验,在小麦-玉米轮作下研究了免耕-深松(NS)、深松-翻耕(SC)、翻耕-免耕(CN)和连年免耕(NN)、深松(SS)、翻耕(CC)等轮耕措施对土壤养分分布及作物产量的影响。结果表明:深松处理(连年深松、免耕-深松)使表层(0~10 cm)土壤与底层(10~20、20~35、35~50 cm)土壤有机质、全氮、全磷、速效磷、速效钾等养分含量差异更大,翻耕或免耕的相对差异较小;在0~50 cm的土层中,硝态氮含量在20~35 cm土层相对较高,且以翻耕(CC)处理的含量最高;铵态氮含量在10~20 cm土层相对较高,以免耕-深松(NS)处理的含量最高;连年深松(SS)处理使土壤全钾表层含量较高。免耕-深松(NS)措施在6种耕作措施中小麦和玉米产量均为最高,显著高于翻耕(CC)、免耕(NN)措施。     

全膜垄作侧播栽培模式下主要旱作马铃薯品种营养品质综合评价

在定西半干旱黄土丘陵区,通过大田试验研究了全膜垄作侧播模式下甘引1号、甘引2号、黑美人、新大坪、青薯9号、庄薯3号、陇薯6号、定薯1号、青薯168等9个主栽马铃薯品种的营养品质性状差异,并采用模糊数学的隶属函数法和因子分析法综合评价了各品种的营养品质,以期为甘肃马铃薯主产区优质马铃薯品种选择提供科学依据。结果表明,全膜垄作侧播栽培技术模式下,9个马铃薯品种综合营养品质顺序依次是甘引1号甘引2号黑美人新大坪青薯9号庄薯3号陇薯6号=定薯1号青薯168。     

旱地棉花有限补水效应研究

研究了旱地棉花不同生育期补水对棉花生长发育和产量的影响．试验结果表明，有限补水棉花根系伤流量提高３７．５％～５６．３％，干物质和叶面积增多，光合势和净光合率提高，叶绿素含量提高２９．８％～４７．１％。补水比不补水棉花产量增加２２．０％～１８３．８％，其中补水３次＞２次＞１％＞ＣＫ，不同干旱年型，有限补水关键时期不同，在前期干旱年型补蕾水，后期干旱年型补花水，补１水（蕾或花）棉花产量过７５０ｋｇ·ｈｍ￣（－２），补２水产量（底＋花或蕾＋花）过１１２５ｋｇ·ｈｍ￣（－２）。     

Changing rainfall patterns and farmers’ adaptation through soil water management practices in semi-arid eastern Kenya

There is limited documentation of soil and water management technologies that enhance adaptation to climate change in drylands of Kenya. Rainfall patterns were analyzed in the semi-arid Machakos and Makueni counties of eastern Kenya using historical data. A total of forty-three smallholder farmers implementing soil water management practices were sampled, and an estimate of the seasonal water budget for current crop and livestock production systems computed. Analysis of rainfall amounts and distribution shows increasing variability, with the average annual total amounts decreasing over the past 50 years. Furthermore, the number of rainy days within the March-April-May season that can support crop growth is gradually decreasing. These decreases are however not significant at P < 0.05. There were more seasons with low rainfall amounts compared to those with high rainfall amounts. All these subject the smallholder crop and livestock production system to limited soil moisture. Farmers address the risk by harnessing and utilizing green (rainfall stored in soil) and blue (rainfall collected into storage tanks) water technologies. The study found that farmers in these semi-arid counties practice fifteen diverse soil and water management interventions on their farms. The most popular practices are cut-off drains, retention ditches, terracing, run-off harvesting, and agroforestry. The estimated seasonal water budget indicates the need for integrated soil and water management interventions to address the crop and livestock production constraints.