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为探究东北黑土区从传统耕作转变为保护性耕作后玉米根系的变化特征,评价保护性耕作的适宜性及微根管技术的可靠性,采用微根管技术对免耕(NT)、旋耕(RT)和条耕(ST)等3种耕作方式下玉米根系进行原位监测,并与传统土钻法进行比较。结果表明,耕作方式对根系形态指标的影响随生育期进行逐渐由表层向深层土壤延伸,影响指标也由少到多。不同耕作方式下超过65%的玉米根系集中分布在0～30 cm土层。苗期以后,ST处理总根长、根长密度明显高于其他处理,但仅在成熟期时差异显著(P<0.05)。耕作方式对根系构型与分布的调控主要通过影响土壤剖面含水量和穿透阻力等来实现。整个土壤剖面ST处理平均含水量最高。0～15 cm土层NT处理土壤穿透阻力显著高于ST和RT处理,最高为1558.20 kPa,15～45 cm土层各处理土壤穿透阻力较为接近。微根管法与土钻法测得的根长密度相对误差基本在10.0%以内。本试验条件下,耕作方式转变可以显著影响根表面积、体积、直径、根长密度等根系特征,土壤水分状况和穿透阻力对作物根系生长具有较大影响。利用微根管法获得的根长密度与土钻法所得结果具有较好的相关性,2种方法相结合... 相似文献
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深松耕作是用深松铲或凿形犁等松土农具疏松土壤而不翻转土层的一种深耕方法,采用这种方式耕作的土地,具有利于作物根系深扎、维持土壤微生物群体、蓄雨贮墒的优点。选用郑单958玉米品种作为试验材料,设置深松耕作试验组(ST)、传统耕作试验组(CT)、免耕对照组(NT)3个组别,记录玉米各个时间节点在田间表现的各项数据,探究深松耕作对于夏玉米根系生长发育和产量的影响。结果发现,随着植物的生长和发育,耕作方式对于夏玉米根系生长造成的影响逐渐明显;相对于免耕来说,耕作能够有效提高夏玉米产量。 相似文献
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根系分泌物对根际土壤关键氮转化过程的影响 总被引：1，自引：0，他引：1
根系分泌物是影响土壤氮素转化、N2O排放和植株氮肥利用率的重要因素之一,也是土壤学、植物营养学、作物生理生态与耕作栽培学、环境科学等学科的重要关注点。为全面认识根系分泌物在土壤氮循环中的作用,综述了根系分泌物的种类和测定方法,介绍了根系分泌物影响土壤关键氮转化过程及N2O排放的机理,根系分泌物对土壤硝化和反硝化过程及N2O排放的抑制作用,并对该领域未来的研究方向进行了展望。为土壤氮素转化的土壤–植物–微生物互作机制研究提供一定参考,以进一步提高氮肥利用率,减少氮肥引起的环境污染。 相似文献
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黑土有机质含量丰富,土壤养分高,是全球最优质的土壤资源之一,更是国家的宝贵战略资源。黑龙江省地处中国东北部,黑土区土壤肥沃,是国家重要的商品粮基地。但是近年来由于水土流失等原因造成黑土肥力下降、黑土层变薄等相关问题,需要全面推行黑土地保护性耕作方法。运用数据分析法,参考文献法等方法,对黑龙江省黑土地保护性耕作实施的基本情况及问题进行分析。在黑土地保护性耕作实施过程中,面临着农户对黑土地保护耕作方式认知程度偏低、技术运用不规范、技术种类和机具数量偏少、缺少黑土地保护性耕作长效机制等现实问题。因此,提议从提高农户认知程度、建立大面积黑土地保护性耕作示范基地、提升政府扶持力度、为黑土地保护性耕作技术研发和装备供给提供专项资金、建立黑土地保护性耕作长效机制等方面建设黑土地保护性耕作的发展之路。 相似文献
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研究了丹江口库区坡耕地传统耕作措施和3种保护性耕作措施对土壤水分动态变化、作物耗水量及作物产量的影响,结果表明：不同耕作方式对土壤水分具有较大的影响,3种保护性耕作措施的全生育期土壤水分含量均高于传统耕作,其中免耕（NT）和免耕秸秆覆盖（NTS）在作物播种期可以显著增加播种期表层土壤含水量;免耕秸秆覆盖对总生物量和玉米产量有显著促进作用,在丹江口库区坡耕地上实施免耕加秸秆覆盖的保护性耕作措施,既有利于作物对水分的高效利用,提高作物产量,也可以减少水土流失和农业面源污染。 相似文献
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土壤容重对高产玉米根系生长的影响及调控研究 总被引：10，自引：0，他引：10
不同土壤容重不同,其稳定性也不同。土壤容重的变化会引起土壤调节水、气、热能力的变化,提高土壤的自动调节能力可以使土壤肥力水平得以提高并满足植物对生长因子的持续需求。为研究土壤物理性质对玉米高产稳产的影响机理,以耕地棕壤为试验材料,采用盆栽方法,研究不同容重对玉米根系生长指标的影响,并进一步研究了施用不同有机肥量及模拟不同耕作深度对玉米根系生长的调控效果。结果表明:在设计容重范围内,容重增加,根系生长指标都表现为下降,容重大于1.2 g/m3时,不同处理根系生长指标差异显著;当容重大于1.3 g/cm3时,不同处理根系活力差异显著。施用有机肥对高容重土壤调控效果更好,有机质含量为4%与5%的处理差异减小,低容重土壤在所设计的有机质水平内调控效果也都较好。耕层厚度增加可以提高根系生长参数,但与对照相比,差异不显著。所以,对于紧实结构性较差的土壤,改善其调节能力应该通过增施有机肥的方法,紧实结构较好的土壤考虑使用耕翻的办法。 相似文献
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耕作与秸秆还田方式对稻田N2O排放、水稻氮吸收及产量的影响 总被引：1，自引：0，他引：1
保护性耕作是改善农田土壤肥力的重要举措,然而其对作物氮吸收与产量的作用尚不明确。为此,本试验于2016—2017年稻季在湖北省武穴市花桥镇,设置常规翻耕与免耕两种耕作方式以及前茬作物秸秆全量还田与不还田两种秸秆还田方法,研究耕作与秸秆还田方式对稻田土壤N2O排放、根系酶活性、水稻氮吸收与产量的影响。结果表明,耕作方式显著影响土壤N2O排放,但不影响根系硝酸还原酶与谷氨酰胺合成酶活性、水稻氮吸收与产量。与翻耕处理相比,免耕处理2016年和2017年土壤N2O排放量分别显著提高了12.5%~18.2%和21.1%~38.6%。秸秆还田显著影响土壤N2O排放量、根系酶活性、水稻氮吸收与产量。相对于秸秆不还田处理,秸秆还田处理2016年和2017年土壤N2O排放量分别显著提高了38.5%~45.5%和13.1%~29.5%。秸秆还田处理相对于不还田处理根系硝酸还原酶与谷氨酰胺合成酶活性分别显著增加了6.7%~45.9%和9.0%~46.7%,水稻氮吸收量提高了12.5%~26.0%,产量增加了9.4%~12.6%。本文认为,虽然秸秆还田提高了水稻氮吸收与产量,但也促进了土壤N2O的排放,因此在评估保护性耕作稻田温室效应时应加强对温室气体(CH4和N2O)排放和土壤碳固定影响的长期监测,以期为发展低碳稻作提供理论依据和技术支撑。 相似文献
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轮耕对小麦–玉米两熟农田耕层构造及作物产量与品质的影响 总被引：12，自引：0，他引：12
为了解不同轮耕模式对小麦-玉米两熟制耕层构造、作物产量和品质的影响,从2009年小麦季开始至2012年玉米生长季结束连续3个种植周期设置小麦季免耕、深松或翻耕+玉米季免耕或深松的6种耕作模式组合,研究其对农田土壤孔隙度和水分含量、作物产量、以及籽粒蛋白质含量、油分含量和容重的影响。结果表明,与免耕相比,玉米季深松大幅度提高0~40 cm土壤的周年总孔隙度,小麦季深松或翻耕改善了土壤孔隙状况。小麦季耕作和玉米季耕作的交互效应是各层次土壤毛管孔隙度的决定因素,而玉米季耕作的独立效应是土壤各层次非毛管孔隙度的决定因素。小麦季深松和翻耕促进小麦生育后期对土壤水分的吸收,深松较翻耕和免耕处理的小麦产量显著升高。玉米季深松比免耕提高了玉米在灌浆阶段对水分的吸收,有利于提高玉米产量,同时对后茬小麦有积极作用。从全年产量与品质看,6种耕作模式组合中,全年两季深松效果最佳,其次是小麦季深松+玉米季免耕,这两种轮耕模式均适合在华北平原推广应用。 相似文献
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周年耕作方式对砂姜黑土农田土壤养分及作物产量的影响 总被引：4，自引：0，他引：4
为探明适宜于砂姜黑土农田的周年耕作方式, 提升砂姜黑土农田地力及作物产量, 在冬小麦?夏玉米一年两熟种植制度下, 设置多年定位夏玉米季?冬小麦季免耕?旋耕(对照)、免耕?深耕、深松?旋耕、深松?免耕、免耕?免耕5种周年耕作方式田间试验, 在定位处理的第4个周年研究耕作方式对砂姜黑土农田土壤有机碳含量、土壤养分及其对作物产量的影响。结果表明, 在秸秆全量还田条件下, 与试验开始前相比, 各处理0~20 cm土层土壤有机碳、全氮、速效钾含量均有所增加。与对照相比, 其他处理均增加周年内0~20 cm土层土壤有机碳和全氮含量。免耕?深耕、深松?旋耕、免耕?免耕处理显著增加周年内0~20 cm土层土壤有效磷含量, 而深松?免耕处理显著增加冬小麦开花期和收获期0~20 cm土层土壤有效磷含量, 整个周年内对照在20~40 cm土层土壤的有效磷含量均最低。深松?免耕处理增加周年内0~20 cm土层土壤速效钾含量, 而深松?免耕、免耕?免耕处理20~40 cm土层土壤速效钾含量在夏玉米苗期、大口期、开花期和灌浆期显著高于对照处理。深松?旋耕和深松?免耕处理显著增加夏玉米?冬小麦周年籽粒产量, 增幅分别为7.67%和10.21%。综上所述, 在秸秆全量还田基础上, 深松?旋耕和深松?免耕能够改善土壤有机碳和养分状况, 显著提高周年作物产量, 可作为黄淮区砂姜黑土农田相对适宜的周年耕作方式。 相似文献
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Strip tillage is a conservative technique widespread overseas with recognized environmental, agronomical and economic benefits. In Europe it has been proposed only recently and is almost unknown by farmers of Italy and other Mediterranean countries, where its compliance with soil and climate environments needs to be evaluated. For this reason, a two-year field trial comparison was carried out between strip tillage, minimum tillage and no tillage for the cultivation of maize in the Po valley, as representative crop and environment for the Italian and Southern Europe intensive agriculture. The aim was to evaluate effects on seedbed quality, weed infestation, and maize performance from crop establishment to final harvest.The experiment was conducted on a sandy-loam soil with high chemical fertility and good water availability for the crop. Strip tillage was carried out by an original passive tool implement hitched to a pneumatic drill operating at a forward speed of around 6 km h−1. We determined soil penetration resistance, bulk density, water content, clod size distribution, ground residue cover, number of weeds along crop rows and between rows, maize drilling depth, crop emergence, biomass accumulation and grain yield.Strip tillage moved less soil and left higher ground residue cover than minimum tillage, while the seedbed prepared by the two techniques did not differ for suitability to drilling, root exploration and crop growth. In fact, maize grown after strip tillage emerged fast and regularly approximating the wished plant density, experienced a limited weed infestation, and showed high total biomass and grain yields, similar to those obtained with minimum tillage. 相似文献
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Excessive tillage compromises soil quality by causing severe water shortages that can lead to crop failure. Reports on the effects of conservation tillage on major soil nutrients, water use efficiency and gain yield in wheat (Triticum aestivum L.) and maize (Zea mays L.) in rainfed regions in the North China Plain are relatively scarce. In this work, four tillage approaches were tested from 2004 to 2012 in a randomized study performed in triplicate: one conventional tillage and three conservation tillage experiments with straw mulching (no tillage during wheat and maize seasons, subsoiling during the maize season but no tillage during the wheat season, and ridge planting during both wheat and maize seasons). Compared with conventional tillage, by 2012, eight years of conservation tillage treatments (no tillage, subsoiling and ridge planting) resulted in a significant increase in available phosphorus in topsoil (0–0.20 m), by 3.8%, 37.8% and 36.9%, respectively. Soil available potassium was also increased following conservation tillage, by 13.6%, 37.5% and 25.0%, and soil organic matter by 0.17%, 5.65% and 4.77%, while soil total nitrogen was altered by −2.33%, 4.21% and 1.74%, respectively. Meanwhile, all three conservation tillage approaches increased water use efficiency, by 19.1–28.4% (average 24.6%), 10.1–23.8% (average 15.9%) and 11.2–20.7% (average 15.7%) in wheat, maize and annual, respectively. Additionally, wheat yield was increased by 7.9–12.0% (average 10.3%), maize yield by 13.4–24.6% (average 17.4%) and rotation annual yield by 12.3–16.9% (average 14.1%). Overall, our findings demonstrate that subsoiling and ridge planting with straw mulching performed better than conventional tillage for enhancing major soil nutrients and improving grain yield and water use efficiency in rainfed regions in the North China Plain. 相似文献
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Crop residue removal and subsoil compaction are limiting to yield improvement in the North China Plain (NCP). We conducted a field study composed of six consecutive crop growing seasons from 2010 to 2013 in Henan province, China, to determine responses of soil properties, crop root distribution and crop yield to tillage and residue management in a wheat–maize cropping system under irrigated conditions. Tillage practices comprised mouldboard ploughing (MP) to a depth of 15-cm, deep mouldboard ploughing (DMP) to a depth of 30-cm, and chisel ploughing (CP) to a depth of 30-cm. Crop residue management included crop residue retained (CRRet) and crop residue removed (CRRem). The results indicated that yields in DMP and CP increased by 6.0% and 7.3% for wheat and by 8.7% and 9.0% for maize, respectively, relative to MP. The CRRet treatment also increased wheat yield by 6.7% and maize yield by 5.0%. The yield increases under DMP and CP were related to reduced bulk density and soil penetration resistance, increased soil water content, improved total N distribution and improved root density (0–60-cm). Compared with MP, the root mass density under DMP and CP were increased by 43.4% and 42.0% for wheat and by 40.6% and 39.4% for maize, respectively. The yield increases under CRRet were also related to increased soil water content, reduced penetration resistance and increased N status (0–40-cm). Overall, for DMP + CRRet and CP + CRRet, a more favorable soil environment alongside greater root mass density and suitable spatial distribution resulted in higher grain yields of wheat and maize. Thus, compared with conventional shallow tillage practice, DMP or CP with residue application could improve soil quality and agricultural productivity under irrigated areas with loam soil in the NCP. 相似文献
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AquaCrop模型在东北黑土区作物产量预测中的应用研究 总被引：1，自引：0，他引：1
东北黑土区是我国玉米和大豆生产基地,为了实现利用AquaCrop模型优化管理和预测产量,本文基于作物小区田间试验和大田观测数据,采用OAT(one factor at a time)法分析了该模型参数的敏感性,率定了敏感性高的参数,并对率定后的模型进行了验证。结果表明:玉米和大豆产量均对影响经济产量的收获指数十分敏感,二者虽然对冠层和根系生长参数都敏感,但有所差异:玉米对冠层衰减系数(canopy decline coefficient,CDC)更为敏感,而大豆则对限制冠层伸展的水分胁迫系数曲线的形状因子(shape factor for water stress coefficient for canopy expansion,Pexshp)更为敏感;玉米因根系深对最大有效根深(maximum effective rooting depth,Zx)更敏感,大豆因根系浅对根区根系伸展曲线的形状因子(shape factor describing root zone expansion,Rexshp)更敏感。由于玉米需水量大,对冠层形成和枯萎前的作物系数(crop coefficient before canopy formation and senescence,KcTr,x)和归一化水分生产力(normalized water productivity,WP*)很敏感,大豆则是一般敏感。率定后模型模拟玉米产量与实测产量的回归系数由0.34提升至0.89,模拟大豆产量与实测产量的回归系数由0.80提升至0.88。进一步用大田实测产量的验证结果表明:预测的玉米与大豆产量与实测产量间回归方程的决定系数(coefficient of determination,R2)分别为0.775和0.779,均方根误差(root mean square error,RMSE)分别为1.076 t hm^–2和0.299 t hm^–2,标准均方根误差(normalized root mean square error,NRMSE)分别为0.097和0.178,模拟效率(model efficiency,ME)分别为0.747和0.730,率定后的AquaCrop模型能较精准地模拟东北黑土区玉米和大豆产量,可用于产量预测或优化管理。 相似文献
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秸秆条带还田对东北春玉米产量、土壤水氮及根系分布的影响 总被引：10，自引：0，他引：10
为探讨秸秆条带还田对东北春玉米产量的影响, 及其与土壤水氮及根系空间分布的关系, 2015年和2016年在辽宁铁岭开展田间试验, 设置垄间旋耕+秸秆还田(RR+S)、垄间旋耕(RR)、隔行垄间旋耕+秸秆还田(IR+S)和隔行垄间旋耕(IR) 4种处理方式。结果表明, 与不还田处理相比, RR+S和IR+S分别增产6.7%和8.2%, 其穗粒数、收获指数均显著增加, 但千粒重差异不显著; RR+S和IR+S处理较RR和IR处理, 30~60 cm土层土壤水分含量提高7.8%和6.1%, 0~30 cm土层土壤全氮含量平均增加6.9%和4.5%。秸秆还田处理较秸秆不还田处理玉米根长密度增加29.4%和22.7%, 其中30~60 cm土层达到显著水平, 根冠比降低21.0%和32.3%, 水分利用效率提高7.8%和7.0%。垄间与隔行垄间处理间水氮空间分布存在明显差异, 垄间处理(RR+S和RR)的土壤水、氮在空间上呈“植株中心两侧含量对称分布”状态, 而隔行垄间处理(IR+S和IR)则呈“植株中心两侧含量不对称分布”状态。说明秸秆条带还田(RR+S和IR+S)通过优化耕层土壤结构及土壤水氮分布, 显著提高了水分利用效率和籽粒产量, 但水氮空间分布对产量未产生直接影响。此外, 干旱年份(2015年)秸秆条带还田的增产效果更为显著, 为东北春玉米高产高效和秸秆综合利用提供有益的借鉴。 相似文献
18.
Northeast black soil area is the production area of maize and soybean in China. In order to optimize the agricultural management and forecast crop yield with AquaCrop model, we use OAT (one factor at a time) method to analyze the sensitivity of the model parameters based on the experiment and field observation data, and to validate the model after calibrated the high sensitivity parameters. The results of sensitivity analysis showed that the yields of maize and soybean were both extremely sensitive to the reference harvest index (HI0) and the parameters of canopy growth and root growth. The difference was that maize was more sensitive to the canopy decline coefficient (CDC), while soybean was more sensitive to the shape factor for water stress coefficient for canopy expansion (Pexshp). Maize was more sensitive to the maximum effective rooting depth (Zx) because of its deep root, while soybean was more sensitive to the shape factor describing root zone expansion (Rexshp) because of its short roots. Maize was extremely sensitive to the crop coefficient before canopy formation and senescence (KcTr,x) and the normalized water productivity (WP*) due to the large water demand, while soybean was only generally sensitive. After calibrated the high sensitivity parameters with experiment data, the regression coefficient of simulated yield and measured yield of maize increased from 0.34 to 0.89, and the regression coefficient of simulated yield and measured yield of soybean increased from 0.80 to 0.88. Furthermore, the validation results of field observation data indicated that the determination coefficients (R2), the root mean square error (RMSE), the normalized root mean square error (NRMSE) and the model efficiency (ME) of the AquaCrop model of maize and soybean were 0.775 and 0.779, 1.076 t hm-2 and 0.299 t hm-2, 0.097 and 0.178, 0.747 and 0.730, respectively. The calibrated AquaCrop model can accurately simulate the yield of corn and soybean in the black soil area of Northeast China, and is useful for yield prediction and optimal management. 相似文献