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玉米秸秆覆盖还田是减少土壤风蚀、保持土壤墒情、增加土壤肥力的一项重要技术,但我国东北春玉米秸秆覆盖面积仍然较小,原因之一是秸秆覆盖还田技术尚不够完善。在欧美国家,秸秆覆盖条耕技术(Strip-till)是实现秸秆覆盖还田的一项重要技术,但在我国应用很少。为此本文综述了国内外秸秆覆盖条耕技术的机械特点、耕作方法及配套管理技术。通过条耕可以将苗带中秸秆清理干净,并疏松土壤,有利用于提高玉米播种质量,实现苗全、苗壮;而行间保持全程秸秆覆盖,有助于减少水分散失。因此条耕结合了秸秆覆盖还田传统耕作的优点。本文认为,秸秆覆盖条耕技术在我国北方土壤风蚀严重、水分缺乏地区有广泛的应用前景,应该加大相关农机农艺综合技术研究,加快该技术的推广应用。 相似文献
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少免耕与秸秆还田对极端土壤水分及冬小麦产量的影响 总被引：35，自引：7，他引：28
为了高效利用天然降雨,缓和农业水资源短缺,该试验在小麦、玉米一年两熟条件下,设置耕作措施和秸秆2个因素,其中耕作措施分为常规耕作、深松耕、耙耕、旋耕、免耕5种,秸秆因素分为玉米秸秆全量还田与不还田,共10个处理,研究了耕作措施与秸秆因素对极端土壤水分和冬小麦产量的效应。结果表明,无论秸秆还田与否,相对于常规耕作,深松耕能提高土壤水分充足期的土壤含水率,增加冬小麦产量,尤其是深松耕秸秆还田,比常规耕作无秸秆还田分别高25.74%和11.45%。秸秆因素在土壤水分充足时影响土壤含水率方面占主导地位,秸秆因素与耕作措施在土壤水分亏缺时影响土壤含水率和冬小麦产量方面均起着重要的作用。免耕、深松耕、耙耕与秸秆还田的交互效应能够增加集雨,提高冬小麦产量。研究结果还表明,冬小麦产量与土壤水分亏缺时土壤含水率相关不显著,而与土壤水分充足期土壤含水率相关显著。 相似文献
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华北平原一年两熟保护性耕作体系试验研究 总被引：51，自引：16，他引：51
冬小麦-夏玉米一年两熟的种植方式在华北地区的农业生产中具有极为重要的地位。但是传统耕作方式使该地区的农业生产不可持续。保护性耕作技术是一种先进的保水保土的生产技术。该文在田间试验的基础上，研究了保护性耕作体系对作物产量、土壤容重、土壤含水率、土壤温度的影响，结果表明：保护性耕作能够提高作物的产量，增加土壤的含水率。其对土壤容重和土壤温度的影响并未对作物的生长产生不利影响。但是，从长远来看，对保护性耕作引起的土壤容重增加、温度降低的问题必须引起足够的重视。结果初步表明：以免耕加覆盖为主的保护性耕作体系可以在华北平原一年两熟地区试验推广。 相似文献
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"三耕六耙九锄田,一季庄稼顶二年。"这一句农谚是江苏省淮阴专区废黄河两岸的农民对旱地耕作经验精练的总结。三耕六耙九锄田即指冬闲期与来年夏收作物的土壤耕作。 相似文献
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在两种不同土壤条件下 (残茬覆盖的固结土壤和前期耕过的疏松土壤 )利用凿形犁进行顺坡 (沿坡向下 )和逆坡 (沿坡向上 )耕作 ,研究不同耕深 (H)、耕速 (v)对土壤输移量 (Q)和土壤侵蚀量的影响。结果表明 :土壤移动的平均距离是坡度、土壤结构、耕深和耕速的函数 ,以这些因子为自变量建立的模型可预测土壤移动距离的变化 ,同时土壤移动距离还与耕具的几何形状有关 ,但此模型未考虑这个因素。利用这个模型绘制在固定耕作方式下的侵蚀诺模图 ,可用来评价耕深、耕速对侵蚀量的影响 ,并可评价防治侵蚀的可行性方案。 相似文献
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土壤健康与农产品优质安全、农业绿色可持续发展密切相关。不同培肥技术对土壤物理功能、化学功能与生物学功能产生较大影响,进而影响土壤健康水平。论文明确了土壤健康的内涵与发展历程,阐述了长期大量施用化肥和不同耕作措施对土壤健康的影响途径,从物理、化学和生物学3个方面总结了有机培肥技术对提高土壤健康的作用机制,并对我国未来土壤健康研究方向提出了展望,以期为培育健康土壤和实现我国农业高质量发展提供理论支撑与技术指导。 相似文献
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差分GPS定位技术在土壤耕作阻力测量中的应用 总被引：13，自引：3，他引：10
为了进行“精细农业”实践,以土壤耕作阻力的测量为例,通过ＤＧＰＳ后处理定位技术,研制开发了农田ＧＩＳ属性数据库数据源获取的硬件系统和软件支持。形成了土壤不同深度层的耕作阻力分布图。 相似文献
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冷凉区旱地玉米保护性耕作土壤环境及产量效应研究 总被引：1，自引：1，他引：0
针对冷凉区旱地玉米生产中存在的干旱缺水、低温冷凉、土壤肥力下降等问题,于2011—2016年采用裂区设计,在山西省旱作节水农业—阳曲县河村示范基地,设置了6种不同耕作覆盖处理,研究旱地玉米保护性耕作的土壤环境及产量效应。结果表明:(1)免耕+二元覆盖、条耕+二元覆盖分别较常规旋耕+地膜覆盖平均增加0—200cm土壤贮水量20.8,32.1mm;免耕+秸秆半覆盖、条耕+秸秆半覆盖分别较常规旋耕+露地种植平均增加0—200cm土壤贮水量24.3,16.3mm。(2)不同耕作处理土壤紧实度差异主要在15cm内,条耕平均为常规旋耕的2.6倍,免耕第1年土壤紧实度最高,为常规耕作的4.6倍,以后逐年下降。(3)免耕+二元覆盖、条耕+二元覆盖分别较常规旋耕+地膜覆盖日平均地温降低0.2,0.1℃(5cm)和0.8,0.3℃(10cm);免耕+秸秆半覆盖、条耕+秸秆半覆盖分别较常规旋耕+露地种植日平均地温降低0.7,0.4℃(5cm)和1.5,1.0℃(10cm)。(4)保护性耕作3年后,免耕和条耕平均较常规旋耕增加0—20cm土壤有机质含量1.5g/kg(覆膜)和1.2g/kg(不覆膜);保护性耕作5年后,土壤培肥效应更加明显。(5)免耕+二元覆盖、条耕+二元覆盖分别较常规旋耕+地膜覆盖平均增产4.4%和6.9%,且条耕+二元覆盖经济产量显著大于常规旋耕+地膜覆盖;免耕+秸秆半覆盖、条耕+秸秆半覆盖、常规旋耕+露地种植平均产量之间没有显著差异。目前来说,适宜该区域的蓄水保墒、培肥土壤、稳产高产的保护性耕作措施为条耕+二元覆盖。 相似文献
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不同耕作方式下旱作玉米田土壤呼吸及其影响因素 总被引：18，自引：4，他引：14
为揭示不同耕作方式对旱作玉米田土壤呼吸的影响,对比研究深松耕、免耕、旋耕和翻耕4种耕作方式下土壤呼吸速率的动态变化及其与土壤水分、温度、有机质、全氮、pH值等的关系。结果表明,夏玉米生长季,4种耕作方式下土壤呼吸速率随生育时期均呈先增加后降低的趋势,平均土壤呼吸速率为深松耕>翻耕>旋耕>免耕;播种前至拔节期土壤温度为翻耕>深松耕>旋耕>免耕,抽雄期至成熟收获期为免耕>旋耕>深松耕>翻耕;各耕作方式下0～20cm层土壤有机质、全氮均逐渐增加,与免耕比较,翻耕有机质和全氮均降低;生育前期土壤pH值波动明显,抽雄期后趋于平缓,土壤pH值平均值为翻耕>旋耕>免耕>深松耕。各影响因素与土壤呼吸速率相关分析表明,深松耕和翻耕土壤水分、温度与土壤呼吸速率呈显著或极显著正相关;有机质与土壤呼吸速率呈负相关,且与深松耕措施下土壤呼吸速率呈显著负相关;除免耕外,其他耕作方式下土壤全氮、pH值与土壤呼吸呈负相关。该研究可为补充完善土壤呼吸排放机理、评估区域碳收支平衡及制定科学有效的土壤碳调控管理措施提供依据。 相似文献
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Anthropogenic effects on soil quality of ancient agricultural systems of the American Southwest 总被引：2，自引：0，他引：2
Soil studies of ancient agricultural fields contribute to research on long-term human–environmental relationships and land use sustainability. This kind of research is especially applicable in desert landscapes of the American Southwest because: (1) soil formation is slow enough that cultivation effects persist for centuries to millennia; (2) many ancient fields in valley margins have remained uncultivated since they were abandoned, so long-term soil properties reflect ancient agricultural use; and (3) agricultural features (e.g., terraces, rock alignments and rock piles, and irrigation canals) provide clues for identifying and sampling ancient cultivated and uncultivated soils. Surficial remnants of these field systems persist and remain intact in many cases. Soil studies of ancient and modern American Indian agricultural systems across the Southwest indicate that soil changes are highly variable, ranging from degradation (e.g., organic matter/nutrient decline, compaction), to minimal net change, to enhanced soil quality. Soil changes caused by cultivation can be inferred by comparing soils in agricultural fields relative to reference uncultivated areas in similar landscape settings (that is, space-for-time substitution). Soil response trajectories vary for a number of reasons, such as variability in initial ecosystem conditions, diversity in agricultural methods, variability in the mix of crops and cropping intensity, and environmental sensitivity to alteration (varying resistance and resilience). Studies of rock mulch soils indicate enhanced fertility, with elevated organic carbon, nitrogen, and available phosphorus levels, increased infiltration rates and moisture retention, and no evidence of compaction. By contrast, cultivation effects vary widely for terraced soils. Although numerous studies have focused on irrigation canals, irrigated soils have received far less attention. Soil studies of irrigation systems along the Gila and Santa Cruz rivers of Arizona now underway will help fill this research gap. 相似文献
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绰墩遗址古水稻土孢粉学特征初步研究 总被引：2，自引：2，他引：0
自1998年以来,绰墩遗址发现了大量的马家浜时期的水稻田.对遗址Ⅵ工作区两个剖面P01和P03进行植硅体和孢粉分析,P01的植硅体分析结果显示在马家浜文化中晚期、马桥文化时期、宋代直至现代,研究点都有水稻生长.孢粉分析还显示,在植硅体浓度较高土壤沉积物中,水生植物花粉在整个孢粉谱中所占比例较小,与现代水田相似.这表明,在新石器时代,人类在种植水稻过程中可能已将杂草除去.绰墩遗址孢粉分析的结果可能为判断古水稻土提供一个有效的方法. 相似文献
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文化遗址区古土壤特性及古环境研究进展 总被引：6，自引：0，他引：6
分析古土壤性质是获取古环境信息的重要手段,通过研究文化遗址区古土壤性质来反映古环境和古人类活动日益成为国内外研究的热点。系统地总结了近年来国内外文化遗址区古土壤的土壤粒度、土壤微形态、土壤元素、土壤磁化率、多环芳烃、动植物遗存等在考古应用方面的研究进展,结果表明上述研究方法有效地反映古环境信息和古人类活动。提出了应借鉴相关研究指标,进一步加强土壤学与考古学的结合,在此基础上丰富文化遗址区古土壤研究方法,加强对文化遗址区土壤的分类研究,逐步建立考古土壤学这一新的学科分支。 相似文献
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In Europe, the actual landscape has been mainly influenced by human activities. Agricultural intensification led to a considerable habitat loss and fragmentation, especially for dry semi-natural grasslands.This current study investigates the impact of former melon and cereal cultivation (cultivation period: 1950-1987) on the semi-natural vegetation of the Crau, representing the last xeric Mediterranean steppe in France.Today, the ex-cultivated melon and cereal fields are characterised by different vegetation compositions, species richness and evenness compared to the undisturbed steppe community. Also the abiotic conditions (N, P, K, pH, soil granule fractions) have been changed by former cultivation practices. The rather transient seed bank of the steppe was depleted during the cultivation periods; ancient weed species and ruderals now determine the seed bank of the ex-cultivated fields.It is concluded that the conservation of the last parts of undisturbed steppe must have absolute priority. A re-development of the original and unique steppe community on formerly cultivated fields may take decades or centuries, if at all. 相似文献
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澧阳平原古水稻土有机质红外光谱特征 总被引：2，自引：0，他引：2
澧阳平原杉龙岗古水稻土遗址剖面中不同耕作年限、不同环境条件、不同深埋的有机质的积累与迁移变化明显。以澧阳平原杉龙岗古水稻土遗址为研究对象,采用溴化钾压片法对剖面中古水稻土和现代耕作水稻土进行红外光谱测定,分析土壤中有机质的官能基团以及各基团的结构特征。结果表明,古水稻土官能基团的振动主要集中在卤素化合物和无机化合物,有机质对古水稻土官能团影响很大,其中,古水稻土中波数1 882 cm-1(烯烃碳)在去有机质后吸收峰弱化;古水稻土中波数为1 631~470 cm-1段,逐渐形成苯环、烯烃化合物且芳构化程度增加,卤素和无机化合物的结合力增强。由一阶导数可知,古水稻土与现代耕作水稻土相差不大,在去有机质后,波峰均被弱化且FD值峰值均小于去有机质前FD值。 相似文献
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中国史前灌溉稻田和古水稻土研究进展 总被引：11，自引：1，他引：10
通过连续4 a多的研究,科学地证明了位于江苏昆山绰墩遗址的稻田群是迄今发现的地球上最早的灌溉稻田群(6 280 a BP),提出了一套诊断古水稻田和古水稻土的技术指标;获得了新石器时期"火耕水溽"——原始灌溉稻作技术的科学证据。阐明了史前水稻土和现代水稻土表层有机质、全氮和全钾含量接近,而全磷、有效磷则是前者大大高于后者的事实,是先民长期以动物残余物肥田的结果。古、今水稻土有机质含量均高于同时期旱地土,揭示了稻田生态系统和水稻土固持大气二氧化碳的巨大潜力。新石器时期水稻土也含有较高的多环芳烃(PAHs)等有机污染物,是源于田间秸秆的焚烧。微生物学的研究表明,史前水稻土产甲烷潜势很低,硝化功能完全丢失。提出了今后应进一步研究的问题。 相似文献
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Ashutosh Mukherjee Satyesh Chandra Roy S. De Bera Hong-En Jiang Xiao Li Cheng-Sen Li Subir Bera 《Genetic Resources and Crop Evolution》2008,55(4):481-485
Hemp (Cannabis sativa L.) cultivation and utilization is an ancient practice to human civilization. There are some controversies on the origin
and subsequent spread of this species. Ancient plant DNA has proven to be a powerful tool to solve phylogenetic problems.
In this study, ancient DNA was extracted from an archaeological specimen of Cannabis sativa associated with archaeological human remains from China. Ribosomal and Cannabis specific chloroplast DNA regions were PCR amplified. Sequencing of a species-specific region and subsequent comparison with
published sequences were performed. Successful amplification, sequencing and sequence comparison with published data suggested
the presence of hemp specific DNA in the archeological specimen. The role of Humulus japonicus Sieb. et Zucc. in the evolution of Cannabis is also indicated. The identification of ancient DNA of 2500 years old C. sativa sample showed that C. sativa races might have been introduced into China from the European–Siberian center of diversity. 相似文献
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《Land Degradation \u0026amp; Development》2017,28(7):2155-2165
Archaeological surveys conducted since the 1980s in the hyper‐arid Uvda Valley of southern Israel revealed extensive lands with runoff harvesting systems for growing barley and wheat during ancient times. Despite the impossibility of dating the earth and stone installations of terraces and limans due to their decay over time, a wealth of ancient agricultural tools located across the valley revealed inhabitation between the Late Neolithic, Chalcolithic, and Early Bronze ages. Also, cropping of barley in the valley's runoff harvesting systems took place until the 1950s by local Bedouin populations. The objective of this study was to assess the valley's agronomic potential under current climatic conditions. This was assessed by the analysis of precipitation (P) and reference evapotranspiration (ETo) data for the rainy seasons during a 17‐year period between 1999–2000 and 2015–2016. Using the ETo data and the single crop coefficient (Kc) for barley and wheat allowed the calculation of crop evapotranspiration (ETc) and the seasonal soil water deficit (D). Hydrological assessment of the valley's basin allowed the calculation of potential runoff volumes which could be available for agricultural use on the valley floor. Overall, the results showed a potential for successful cereal cultivation only in one to two years during this 17‐year period. This revealed no viability for local agriculture under current climatic conditions. Insights from this study consist with other studies which indicated considerably drier climatic conditions at present compared to those in ancient times, and even compared to those in the mid‐twentieth century. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献