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Search Results: 1 - 10 of 36296 matches for " 汪有科 "
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果实膨大期两种旱作管理技术对梨枣的增产研究
赵霞,
北方园艺 , 2015, DOI: 10.11937/bfyy.201513003
Abstract: 以9年生梨枣树(ZiziphusjujubeMill.)为试材,在无灌溉条件下,通过2种旱作管理技术处理,研究节水型修剪技术和竹节式聚水沟技术对梨枣枣吊、坐果及产量的影响。结果表明节水型修剪技术与竹节式聚水沟技术的单独及联合实施,均提高了结果枣吊数量及枣吊的坐果能力,提高梨枣的产量;与对照相比,节水型修剪技术(HL)可提高产量83.14%,竹节式聚水沟技术(CJ)可提高产量38.44%,节水型修剪技术+竹节式聚水沟技术(HJ)效果最好,产量可提高155.00%。研究认为,在旱地无灌溉条件下的陕北黄土丘陵区应该以节水型修剪为主,最好结合节水型修剪在林下采用聚水沟措施。
“?润”抗旱营养缓释剂对大葱生长和产量的影响
张潘,徐福利,
北方园艺 , 2012,
Abstract: 采用田间试验,研究了“?润”抗旱营养缓释剂穴施和浸种对大葱生长和产量的影响。结果表明“?润”抗旱营养缓释剂采用穴施和浸种都显著促进了大葱的生长,提高了产量和商品性,高度增加20.0%~32.8%,产量增加24.0%~44.2%,葱白长度增加20.2%~22.4%,生长期缩短了8~10d。穴施的效果优于浸种。表明该抗旱营养缓释剂具有在大葱种植区推广应用的价值。?
黄土丘陵区土壤粒径分布单重分形和多重分形特征
白一茹,
农业机械学报 , 2012, DOI: 10.6041/j.issn.1000-1298.2012.05.008
Abstract: 利用单重分形和多重分形方法定量分析黄土丘陵区土壤粒径分布(PSD)特征,同时分析土地利用方式对PSD分形参数的影响。结果表明:研究区PSD呈现出非均匀分布,具有多重分形特征,PSD多重分形谱f(α)-α为不对称的上凸曲线。容量维数D0与土壤质地相关性不明显,信息维数D1、关联维数D2和多重分形谱宽Δα均与粘粒体积分数呈极显著正相关(P<0.01)。土地利用方式对粘粒、粉粒、砂粒体积分数和Dsilt值有显著影响(P<0.01)。多重分形分析为详细描述PSD提供了精确的方法和途径。
四川省et0空间变异情况研究
吴贤忠,
人民黄河 , 2010,
Abstract: ?偏度和峰值检验表明,et0数据满足正态分布,可以直接运用克里格方法进行插值.通过对样本最大值和最小值的不同模型预测误差均值、预测误差均方根和标准均方根预测误差的比较表明:运用克里格方法进行插值时应首选高斯模型.根据插值得到的et0等值线图,可清晰地看出区域et0值的大致范围,为计算作物需水量提供依据.
香花豌豆地下滴灌毛管埋设深度试验研究
姜志水,吴普特,
人民黄河 , 2008,
Abstract: ?采用10、25、40cm3种地下滴灌带埋深,对香花豌豆田间土壤水分及香花豌豆生长进行了试验.结果表明,埋深25cm的处理香花豌豆长势最好,滴水后地表部分被湿润,其日蒸发量为0.29mm,是埋深10cm的41.4%,地下最大湿润半径可达50cm.另外,滴灌带铺设间距在100cm以内可较好地满足作物需水要求,地下滴灌带埋深在30cm左右可有效减少水分蒸发.
地下滴灌埋设深度对紫花苜蓿生长的影响
夏玉慧,,治同
草地学报 , 2008, DOI: 10.11733/j.issn.1007-0435.2008.03.017
Abstract: 研究不同滴灌带埋设深度对紫花苜蓿金皇后(MedicagosativaL.cv.GoldenEmpress)的株高、茎粗、分枝数、根系和产量等指标的影响,以期为滴灌在人工牧草种植应用提供理论依据.结果表明株高和茎粗两指标,在分枝期,埋深10cm显著高于其它处理(P<0.05);开花期以后,埋深30cm显著高于其它处理(P<0.05);不同埋深处理分枝数差异不显著;分枝期埋深10cm产量最高,开花期以后埋深为20和30cm产量逐渐提高甚至超出10cm滴灌处理;不同埋设深度对主根生长影响不大,但每个滴灌带埋深处的侧根密度增加.
山地枣树茎直径对不同生态因子的响应
赵英?,,韩立新?,星?
生态学报 , 2012,
Abstract: 以山地梨枣为试材,进行了枣树茎直径对土壤水势(wps)、太阳辐射(rs)、气温(ta)、空气相对湿度(rh)等生态因子的响应试验研究。试验共设4个wps区间的处理,连续测定枣树茎直径及不同生态因子的动态变化。结果表明:在果实膨大期,在-41——390kpa范围内,wps越高的处理,其枣树茎直径(td)越大;不同处理间枣树最大茎直径(mxtd)存在显著性差异,较高的wps区间有利于茎直径的增加;mxtd是该期较为适宜的水分信息诊断指标。晴天时,茎直径日收缩幅度大;雨天白天时,茎直径基本处于同一水平,收缩不明显。td与rh呈极显著正相关,与ta呈极显著负相关关系,与rs间无显著相关关系,rh与ta是影响茎直径变化的最主要气象因子。综合考虑,枣树茎直径的微变化同时受到各种生态因子的影响,尤以rh、ta、wps的影响更为显著;wps高时,wps为影响茎直径变化的主要因子;wps低时,rh成为影响茎直径变化的主要因子。
Response of pear-jujube to different soil water potentials during budding and flowering stages
萌芽开花期梨枣对土壤水势的响应

韩立新,,张琳琳
中国生态农业学报 , 2012,
Abstract: Pear-jujube is widely cultivated in the Loess Plateau Region (LPR) of China where it is used to reforest farmlands. Pear-jujube culture was previously constrained by wasteful use of limited water resources that characterized traditional irrigation, restricting local agricultural development. It was therefore vital to study water demand at different growth stages of pear-jujube. This paper discussed the response of 4-year-old pear-jujube trees to different soil water potentials. Both vegetative and reproductive growth processes were studied in commercial pear-jujube orchards in Mengcha Village of Mizhi County, Shaanxi Province. Four levels of soil water potentials -31~-51 kPa, -41~-84 kPa, -59~-132 kPa and -161 kPa (no irrigation treatment)] were set up to determine suitable soil water potentials at budding and flowering stages of pear-jujube. While soil water potential was measured using the equilibrium tensiometer (EQ15), trunk diameter fluctuation was measured using the linear variable displacement transformers (LVDT). The results showed that in different soil water potentials, trunk diameter fluctuation and vegetative and reproductive growths among treatments were significantly different (P < 0.05). During the budding stage, suitable soil water potential was in the range of -41~-84 kPa, in which pear-jujube vegetative and reductive growths were flourished with the least maximum daily shrinkage (MDS) among the treatments. However, the suitable soil water potential for pear-jujube flower bud differentiation was in the range of -41~-132 kPa. Although mild water stress did not adversely affect flower bud differentiation during budding stage, vegetative growth dropped and vegetative-reproductive growth relationship optimized. As at soil water potential range of -54~-78 kPa during flowering stage, MDS dropped to lowest point while fruit setting percent was highest. The most suitable soil water potential at pear-jujube flowering stage was therefore in the range of -54~-78 kPa. Also the most suitable soil water potential for pear-jujube fruit setting was in the range of -79~-114 kPa, in which fruit setting percent was highest. Hence at flowering stage, mild water stress increased fruit setting. At budding and flowering stages, water-logging and severe water-stress limited vegetative and reproductive growths and reduced fruit setting percent. However, water-logging enhanced trunk growth and severe water-stress retarded trunk growth. Furthermore, no real need of irrigating pear-jujube at budding stage was noted during normal years. This was because precipitation was enough for sprouting, lamina opening and flower bud development. However, precipitation alone was not enough at pear-jujube flowering stage during normal years.
黄土丘陵半干旱区密植枣林随树龄变化的根系空间分布特征
马理辉, 吴普特,
植物生态学报 植物生态学报 , 2012, DOI: 10.3724/SP.J.1258.2012.00292
Abstract: ?该文研究了黄土丘陵半干旱区密植枣(Ziziphusjujuba‘Lizao’)林群体根系随树龄变化的空间分布特征。对1年生、4年生、8年生和11年生4种树龄的密植枣林采用剖面法,获得0–1m土壤剖面上直径>3mm、1–3mm及<1mm的根系数量和空间位置信息。利用方差分析,评价了山地密植枣林林分根系随树龄变化的水平和垂直分布特征。结果表明:3种直径的根系数量均随着树龄的增长而增加,直径<1mm的根系增长速度最快;随着土层加深,根系数量递减,1年生枣林的根系主要聚集在0–40cm土层中,4年生及以上树龄的根系主要分布在0–60cm土层中;0–1m土层内,1年生枣林(株距1.2m)及4年以上树龄(株距2m),同树龄枣林中直径<1mm的根系水平分布无差异;同一土层中(0–20cm,20–40cm,40–60cm),无论树龄大小及离树干的水平位置如何,不同直径根系的数量都无差异。研究表明:在有水肥管理措施的条件下,枣林根系垂直方向形成浅层型的适应模式;在密植环境下,枣林细根形成根网型的适应模式。
基于茎直径微变化的梨枣灌溉指标的初步研究
韩立新,,李晓彬
园艺学报 , 2012,
Abstract: 研究了4年生酸枣砧梨枣(ziziphusjujubamill.)植株主干茎直径微变化指标对土壤水势(swp)变化的响应规律,以及与气象要素的关系。结果表明:土壤水势降低引起茎直径日最大收缩量(mds)增大,日生长量(dg)、生长速率(tgr)和日最大值(mxtd)降低。在水分亏缺发展阶段和水分亏缺维持阶段,mds和tgr的噪声信号(变异系数)较小,信号强度与噪声信号的比值较大,表明其对土壤水势变化反映敏感。此外,mds、tgr与潜在蒸散量(et0)、正午水汽压亏缺(vpdmd)等气象因子的相关性显著,均能反映大气的干旱程度,因此tgr和mds可作为梨枣水分亏缺的诊断指标。
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