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1.
The adoption of annual subsoiling as conservation tillage in dryland maize and wheat cultivation in northern China 总被引：9，自引：0，他引：9
He Jin Li Hongwen Wang Xiaoyan A.D. McHugh Li Wenying Gao Huanwen N.J. Kuhn 《Soil & Tillage Research》2007,94(2):493-502
Soil compaction caused by random traffic or repetitive tillage has been shown to reduce water use efficiency, and thus crop yield due to reduced porosity, decreased water infiltration and availability of nutrients. Conservation tillage coupled with subsoiling in northern China is widely believed to reduce soil compaction, which was created after many years of no-till. However, limited research has been conducted on the most effective time interval for subsoiling, under conservation tillage. Data from conservation tillage demonstration sites operating for 10 years in northern China were used to conduct a comparative study of subsoiling interval under conservation tillage. Three modes of traditional tillage, subsoiling with soil cover and no-till with soil cover were compared using 10 years of soil bulk density, water content, yield and water use efficiency data. Cost benefit analysis was conducted on subsoiling time interval under conservation tillage. Yield and power consumption were assessed by based on the use of a single pass combine subsoiler and planter. Annual subsoiling was effective in reducing bulk density by only 4.9% compared with no-till treatments on the silty loam soils of the Loess plateau, but provided no extra benefit in terms of soil water loss, yield increase or water utilization. With the exception of bulk density, no-till and subsoiling with cover were vastly superior in increasing water use (+10.5%) efficiency and yield (+12.9%) compared to traditional tillage methods. Four years of no-till followed by one subsoiling reduced mechanical inputs by 62%, providing an economic benefit of 49% for maize and 209% for wheat production compared to traditional tillage. Annual subsoiling reduced inputs by 25% with an increased economic benefit of 23% for maize and 135% for wheat production. Yield and power consumption was improved by 5% and 20%, respectively, by combining subsoiling with the planting operation in one pass compared with multipass operations of subsoiling and planting. A key conclusion from this is that annual subsoiling in dryland areas of northern China is uneconomical and unwarranted. Four years of no-till operations followed by 1 year subsoiling provided some relief from accumulated soil compaction. However, minimum soil disturbance and maximum soil cover are key elements of no-till for saving water and improving yields. Improved yields and reduced farm power consumption could provide a significant base on which to promote combined planter and subsoiling operations throughout northern China. Further research is required to develop a better understanding of the linkages between conservation tillage, soil quality and yield, aimed at designing most appropriate conservation tillage schemes. 相似文献
2.
Cong He Jia-Rui Niu Cheng-Tang Xu Shou-Wei Han Wei Bai Qiu-Lai Song Yash Pal Dang Hai-Lin Zhang 《Soil Use and Management》2022,38(2):1146-1161
Northeast China, the important grain-producing region in China, is under threat from soil degradation because of long-term conventional tillage (CT). The adoption of conservation tillage is anticipated to restore soil fertility, maintain crop yields and enhance sustainability. However, the integrated effects of conservation tillage practice on crop yields and soil organic carbon (SOC) remain unclear. In this meta-analysis of peer-reviewed studies conducted in the Northeast China region, we assess crop yields and SOC values under no-till, ridge tillage and subsoiling tillage practices. The results indicate that in areas with mean annual temperatures (MAT) below 3°C, crop yields were significantly (p < .05) higher under ridge tillage (0.8%) and subsoiling tillage (13.1%) compared with CT, whereas yields reduced under no-till (−3.7%). Ridge tillage generally had a similar effect on crop yield as no-till, without the negative impact in colder regions. We also report that no-till practice increased SOC concentrations by 24.1%, 43.9% and 17.4% in areas of higher temperature (MAT > 6°C), low mean annual precipitation (MAP) (<500 mm) and continuous cropping conditions, respectively. Ridge tillage and subsoiling tillage also had positive effects on SOC concentrations (to a lesser degree than no-till), indicating that conservation tillage can enhance SOC in Northeast China. Overall, the implementation of different conservation tillage measures in Northeast China was found to enhance crop yields and sequester carbon. We recommend that ridge tillage is used in colder areas and that subsoiling tillage is used in rotation with other tillage measures to maintain crop yields. 相似文献
3.
中国北方保护性耕作条件下深松效应与经济效益研究 总被引：53，自引：19，他引：53
保护性耕作技术是适应中国北方农业发展的一种新型耕作技术，它可以通过深松作业来消除因多年免耕出现的土壤变硬问题。目前对保护性耕作条件下深松的效应和经济效益缺乏深入的研究，在玉米深松过程中还出现的伤苗，功耗大和经济效益低等问题。该文试验研究了在中国北方保护性耕作示范基地上，从1993年开始，通过10多年的时间对保护性耕作条件下的深松效应，测定了传统耕作、深松覆盖和免耕覆盖3种不同耕作方式下的土壤容重、含水率，水分利用率和产量等数据，试验结果表明，在保护性耕作条件下，每4年对土壤深松一次可以解决土壤变硬问题，持续保持作物高的水分利用率和产量，并不需要年年深松。相对深松覆盖(年年深松)，4年免耕覆盖＋1年深松的耕作方式能提高25%左右的经济效益。同时，针对玉米深松过程中的问题，提出了玉米免耕播种和深松联合作业的方案，试验表明，玉米免耕播种和深松联合作业能有效解决玉米深松过程中出现的一系列问题，促进玉米生长，提高玉米产量，建议在中国北方玉米产区推广这一联合作业技术。 相似文献
4.
中国北方一年两作区保护性耕作技术研究 总被引：3，自引：0，他引：3
该文主要研究适于中国北方半湿润偏旱区一年两作保护性耕作的技术模式。介绍了在“杨凌农业机械化保护性耕作新技术新机具试验示范园地"建立的小麦玉米一年两作区10种不同机械化保护性耕作的模式、试验方案以及自主研制开发的配套机具的性能;将不同模式与传统犁耕作业模式进行了对比试验与分析研究。结果表明：小麦生长全程秸秆粉碎还田、麦收后玉米免耕播种作业模式与传统犁耕无秸秆覆盖相比,小麦增产53%,玉米增产25％,土壤蓄水量增加1%～1.2%,各类保护性耕作模式土壤有机质平均增加1.03 g/kg 。另外,深松作业增产节水效果优于深耕作业;前茬小麦高留茬玉米免耕播种效果优于低留茬的玉米免耕播种。经济分析还表明,由于作物增产并降低了机械作业成本,保护性耕作技术模式的经济效益明显优于传统犁耕作业。 相似文献
5.
Even though conservation tillage may be ideal for the semi-arid tropics (SAT) in view of results from studies and tillage practices in the U.S.A. and Australia, studies conducted in semi-arid regions of Africa appear to support the use of conventional tillage systems. Some of the reasons for this apparent discrepancy are because of the physical properties of the soils in semi-arid Africa, particularly the Sahelian zones where the soils are sandy, have high bulk densities and therefore low total porosities and form crusts upon wetting and drying. Consequently, no-till or reduced tillage systems that do not have the soil surface covered by residue in irder to prevent formation of crust as a result of raindrop impact, tend to lose water through runoff in a region where water economy is essential. Also, because these soils have inherently high bulk densities, conventional tillage systems appear to be suitable since they increase the macropores, reduce both bulk density and strength and thus ensure prolific root distribution and the resultant exploration of water and nutrients at greater soil depths. Notwithstanding, it seems that since most of the SAT soils are structurally unstable, further conventional tillage even though it has ephemeral advantages, may in the long term be exacerbating the problems of structural instability and their deleterious effect on water and soil conservation and therefore on crop production. We suggest that at this stage soil tillage research in the semi-arid regions of Africa and Asia should re-examine some of the concepts of conservation tillage in relation to soil physical properties and processes in order to obtain a tillage system that ensures high crop yields without destruction of the soil resource. 相似文献
6.
不同耕作方式对豫西旱区坡耕地水肥利用与流失的影响 总被引：24，自引：4，他引：24
为筛选适宜豫西早坡地应用的耕作技术，对深松覆盖、免耕覆盖、一次深翻和传统耕作等4种耕作方式的土壤水分、养分及其利用与流失情况进行了研究，结果表明：深松覆盖、免耕覆盖能提高土壤蓄水量，土壤有机质和氮、磷、钾含量明显高于传统耕作，特别是对上层土壤全氮及碱解氮和深层土壤的有效磷及速效钾的影响更为明显，并能有效地减少地表产流次数和径流量，减少土壤养分的流失，提高水分利用效率和养分的生产效率，显著提高小麦产量。与传统耕作相比，深松覆盖和免耕覆盖水分利用效率提高16．37％和10．62％，氮素生产效率提高17．40％和10．27％，磷素生产效率提高19．80％和12．54％，钾素生产效率提高19．44％和12．19％，小麦产量提高23．22％和15．38％，经济效益提高29．36％和21．13％。 相似文献
7.
摘要：基于公开发表文章中有关东北地区保护性耕作下大豆农田土壤温度和湿度数据，以传统耕作（CT）为对照，免耕（NT）、少耕（RT）、秸秆覆盖（SM）、免耕秸秆覆盖（NTSM）为处理，应用Meta分析方法定量评估保护性耕作措施对东北大豆农田土壤水热状况的影响程度。结果表明：与CT相比，保护性耕作总体上使东北大豆农田0-170cm土层的土壤体积含水量增加了9.2%，使浅层土壤（0-30cm）温度降低了8.2%；不同气候条件下4种保护性耕作措施均能提高土壤湿度；秸秆覆盖可以提高大豆整个生育时期土壤含水量，且在营养生长期对土壤水热的影响最大，土壤温度随秸秆覆盖量的增加而增加；保护性耕作措施降低土壤温度的幅度随着土壤黏粒减少而降低，提高土壤湿度的幅度随土壤深度增加而降低；免耕秸秆覆盖在不同土壤深度的蓄水保墒效果最明显，在0-20cm土层提高了32.9%的土壤湿度。综上，保护性耕作措施较传统耕作具有增湿降温效应，气温、降水、生育时期、秸秆覆盖量、土壤类型及土壤深度均对保护性耕作下大豆农田的土壤水热状况产生影响。 相似文献
8.
Short-term organic matter mineralisation following different types of tillage on a Swedish clay soil
Reduced tillage is proposed as a method of C sequestration in agricultural soils. However, tillage effects on organic matter turnover are often contradictory and data are lacking on how tillage practices affect soil respiration in northern Europe. This field study (1) quantified the short-term effects of different tillage methods and timing on soil respiration and N mineralisation and (2) examined changes in aggregate size distribution due to different tillage operations and how these relate to soil respiration. The study was conducted on Swedish clay soil (Eutric Cambisol) and compared no-tillage with three forms of tillage applied in early or late autumn 2010: mouldboard ploughing to 20–22 cm and chisel ploughing to 12 or 5 cm depth. Soil respiration, soil temperature, gravimetric water content, mineral N and aggregate size distribution were measured. The results showed that respiration was significantly higher (P?<?0.001) in no-till than in tilled plots during the 2 weeks following tillage in early September. Later tillage gave a similar trend but treatments did not differ significantly. Soil tillage and temperature explained 56 % of the variation in respiration. In the early tillage treatment, soil respiration decreased with tillage depth. Mineral N status was not affected by tillage treatment or timing. Soil water content did not differ significantly between tillage practices and therefore did not explain differences in respiration. The results indicate that conventional tillage in early autumn may reduce short-term soil respiration compared with chisel ploughing and no-till in clay soils in northern Europe. 相似文献
9.
Double cropping of soybean has progressed less rapidly in the U.S. Southeastern Coastal Plains than expected by the ample rainfall and long frost-free season. Post-emergence herbicides, the management of plant residues to reduce water use by cover crops, and a no-till planter with a combination subsoiler are the innovations that have facilitated this new production. Full-season soybean (Glycine max L.) was planted following a grazed cover crop of winter rye (Secale cereale L.) or late-season soybean was planted following winter wheat harvest. In both cases, a special planter was used with an integral subsoil shank ahead of the opener. Full-season soybean under conservation tillage produced yields equal to or better than yields in conventional clean tillage. In a dry summer, soybean yields under conservation tillage exceeded conventional tillage because of suppressed early biomass production which conserved stored soil water and favored growth during the reproduction phase of the crop-cycle. Late-season soybean yields behind wheat favored the conservation tillage practice of in-row subsoil-planting into stubble. However, planting in burned-off wheat stubble produced the highest yields in this study. In a dry spring, the cover crop accelerated soil water use which resulted in lower soybean yields under conservation tillage. Comparisons of 76 vs. 97 cm row spacing were inconclusive, but the trend suggests that wider rows conserve water under periods of drought and that the narrower-row configuration favors adequate water regimes. 相似文献
10.
保护性耕作与等高草篱防治坡耕地水土及氮磷流失研究 总被引：5，自引：0，他引：5
坡耕地是水土流失和农业面源污染物的重要来源,同时也是当前治理的薄弱环节。本文以北京地区坡耕地为研究对象,采用人工模拟降雨方法,研究了保护性耕作和等高草篱措施在不同坡度条件下对水土及氮磷流失的防治效果。结果表明:保护性耕作和等高草篱措施均能有效降低坡耕地水土及氮磷养分流失,4种处理的降低效果由大到小依次为:保护性耕作+草篱>传统耕作+草篱>保护性耕作+无草篱>传统耕作+无草篱。与传统耕作+无草篱相比,传统耕作+草篱、保护性耕作+无草篱、保护性耕作+草篱分别减少56%、44%和68%的径流流失,66%、49%和82%的土壤流失,以及56%、43%和66%的总氮流失和54%、40%和70%的总磷流失。同时,等高草篱和保护性耕作措施的防治效果与坡度呈负相关关系,即随着坡度增加其作用效果逐渐减弱。回归分析结果表明,保护性耕作和等高草篱措施是控制坡耕地水土及氮磷流失的最关键因素。 相似文献
11.
Y.X. Li J.N. Tullberg D.M. Freebairn N.B. McLaughlin H.W. Li 《Soil & Tillage Research》2008,100(1-2):25-33
Soil water conservation is critical to long-term crop production in dryland cropping areas in Northeast Australia. Many field studies have shown the benefits of controlled traffic and zero tillage in terms of runoff and soil erosion reduction, soil moisture retention and crop yield improvement. However, there is lack of understanding of the long-term effect of the combination of controlled traffic and zero tillage practices, as compared with other tillage and traffic management practices.In this study, a modeling approach was used to estimate the long-term effect of tillage, traffic, crop rotation and type, and soil management practices in a heavy clay soil. The PERFECT soil–crop simulation model was calibrated with data from a 5-year field experiment in Northeast Australia in terms of runoff, available soil water and crop yield; the procedure and outcomes of this calibration were given in a previous contribution. Three cropping systems with different tillage and traffic treatments were simulated with the model over a 44-year-period using archived weather data.Results showed higher runoff, and lower soil moisture and crop production with conventional tillage and accompanying field traffic than with controlled traffic and zero tillage. The effect of traffic is greater than the effect of tillage over the long-term. The best traffic, tillage and crop management system was controlled traffic zero tillage in a high crop intensity rotation, and the worst was conventional traffic and stubble mulch with continuous wheat. Increased water infiltration and reduced runoff under controlled traffic resulted in more available soil water and higher crop yield under opportunity cropping systems. 相似文献
12.
Trends in tillage practices in relation to sustainable crop production with special reference to temperate climates 总被引：4，自引：0，他引：4
The concept and some definitions of sustainable agriculture are reviewed. Most of these definitions include economic, environmental and sociological aspects. The finite area of land emphasizes the need for consideration of soil conservation and of soil quality in relation to sustainability. An important element of soil quality is rooting depth. Therefore loss of soil by erosion is a dominant factor in long-term sustainability. The effects of tillage on soil parameters in minimum data sets that have been proposed to describe soil quality are reviewed. Soil organic matter may be one of the most important soil quality characteristics in relation to tillage because of its influence on other soil physical, chemical and biological properties. Conservation tillage practices can increase the organic matter content, aggregate stability and cation exchange capacity (CEC) of the topsoil. However, bulk density and penetrometer resistance are also increased, especially with zero tillage. Although such soil quality parameters may form a basis for describing some of the consequences of particular tillage practices, they do not provide a basis for predicting the outcome in terms of crop growth and yield. This is both because critical values of soil quality parameters have not been defined and because in some soils biopore formation in zero or minimally tilled land can modify the soil for water movement and for root growth and function.
The effects of tillage on crop growth and yield in long-term experiments are reviewed. The review only includes experiments in North America, Europe and New Zealand that have lasted 10 years or more to allow for seasonal variation in weather, possible progressive changes in soil conditions and the learning phase often experienced when new tillage methods are used. While there is a good deal of variation in the results of these tillage experiments some patterns have emerged. In long-term experiments, yields of maize in Europe and the US and soybeans in the US have been similar after ploughing and no-tillage, especially on well-drained soils. In Europe, yields of winter cereals have also been similar after traditional and simplified tillage but yields of spring cereals have sometimes been less after direct drilling than ploughing.
Trends in tillage practices are reviewed. Conservation tillage in the US is increasing and is used on about 30% of cropland, including no-till on about 10% of cropland. This increase in use of conservation tillage is mainly attributed to the legal requirement for farmers who are in government price support programs to adopt conservation plans which may involve conservation tillage. However, the allowable rates of erosion in these plans are likely to be in excess of rates of erosion for long-term sustainability. Survey information on tillage practices needs to be considered in relation to predictions on suitability of conservation tillage based on experimental results. In the semi-arid prairies of Canada there is a trend toward fewer cultivation operations, but in eastern Canada the mouldboard plough is still the dominant tillage method. In Europe although erosion is less obvious it is believed to be increasing, but minimum tillage is not widely used. This is because of the need to remove at least some straw for successful minimum tillage in sequential winter wheat and barley crops, but there are few economic uses for straw, and burning is illegal in many countries. In the more moist cooler conditions of Europe grass weed proliferation is another constraint, at least with present technology. So far, the overall success of conservation tillage has not been limited by the growing problem of genetic resistance of weeds to herbicides. Societal attitudes to the continued use of herbicides may pose longer-term problems for some conservation tillage practices. 相似文献
13.
耕作对坡耕地水土流失和冬小麦产量的影响 总被引：9，自引：5，他引：9
在模拟降雨和自然降雨条件下研究长期（6年）定位耕作措施对豫西早区坡耕地水分保持、土壤流失以及冬小麦产量的影响。耕作措施包括少耕、免耕覆盖、深松覆盖和常规耕作。田间模拟降雨试验用来测定不同耕作措施对径流和土壤流失的影响，自然降雨小区主要用来验证模拟试验结果，同时测定不同耕作措施对冬小麦产量的影响。模拟试验结果表明：不同耕作措施下的土壤饱和导水率没有明显差异，雨前土壤含水量和降雨强度均显著影响地表径流。在试验条件下，免耕覆盖处理未产生径流和土壤流失，水土保持效果最好。与常规耕作比较，深松覆盖处理分别减少径流和土壤流失50％和90％。尽管少耕可以有效降低土壤流失，但其产生的径流量和常规耕作相近。在自然降雨条件下，免耕覆盖和深松覆盖的水土保持效果从第3年开始显著。深松覆盖在任何年型均能够显著提高冬小麦的产量。相比较常规耕作，深松覆盖平均增产9．4％。免耕覆盖除丰水年也能显著提高冬小麦产量．但增产效果不如深松覆盖显著。少耕无明显增产效果。由于产量对农民来说是评判一个耕作措施效果的重要依据，同时考虑到深松覆盖显著的水土保持效果，我们认为深松覆盖是适合当地早作农业的一个有效耕作措施。 相似文献
14.
Tillage and cropping effects on soil quality indicators in the northern Great Plains 总被引：9，自引：5，他引：9
The extreme climate of the northern Great Plains of North America requires cropping systems to possess a resilient soil resource in order to be sustainable. This paper summarizes the interactive effects of tillage, crop sequence, and cropping intensity on soil quality indicators for two long-term cropping system experiments in the northern Great Plains. The experiments, located in central North Dakota, were established in 1984 and 1993 on a Wilton silt loam (FAO: Calcic Siltic Chernozem; USDA1: fine-silty, mixed, superactive frigid Pachic Haplustoll). Soil physical, chemical, and biological properties considered as indicators of soil quality were evaluated in spring 2001 in both experiments at depths of 0–7.5, 7.5–15, and 15–30 cm. Management effects on soil properties were largely limited to the surface 7.5 cm in both experiments. For the experiment established in 1984, differences in soil condition between a continuous crop, no-till system and a crop–fallow, conventional tillage system were substantial. Within the surface 7.5 cm, the continuous crop, no-till system possessed significantly more soil organic C (by 7.28 Mg ha−1), particulate organic matter C (POM-C) (by 4.98 Mg ha−1), potentially mineralizable N (PMN) (by 32.4 kg ha−1), and microbial biomass C (by 586 kg ha−1), as well as greater aggregate stability (by 33.4%) and faster infiltration rates (by 55.6 cm h−1) relative to the crop–fallow, conventional tillage system. Thus, soil from the continuous crop, no-till system was improved with respect to its ability to provide a source for plant nutrients, withstand erosion, and facilitate water transfer. Soil properties were affected less by management practices in the experiment established in 1993, although organic matter related properties tended to be greater under continuous cropping or minimum tillage than crop sequences with fallow or no-till. In particular, PMN and microbial biomass C were greatest in continuous spring wheat (with residue removed) (22.5 kg ha−1 for PMN; 792 kg ha−1 for microbial biomass C) as compared with sequences with fallow (SW–S–F and SW–F) (Average=15.9 kg ha−1 for PMN; 577 kg ha−1 for microbial biomass C). Results from both experiments confirm that farmers in the northern Great Plains of North America can improve soil quality and agricultural sustainability by adopting production systems that employ intensive cropping practices with reduced tillage management. 相似文献
15.
A review of tillage systems in Latin America revealed that considerable research on this topics has been done and much is currently in progress. Results of most of this tillage research, however, have not been published in international refereed journals, thus making it difficult to assess the current state of the art on this topic. A high percentage of tillage research results has not been published at all. In general, conservation tillage practices, that is, those commonly referred to as no-till and minimum till, had higher bulk densities in the surface soil, but lower macroporosities, infiltration rates and crop yields as compared with conventional tillage, which was typically disk plowing. Chisel plowing and subsoiling, deep tillage practices whose action extends below the usual depth of disk plowing, usually decreased mechanical impedance, improved root penetration and increased crop yields. Soil loss from cropped land was usually greatest under conventional tillage unless mulch was applied to the soil surface. We believe that some form of tillage practice that mixes the surface soil layer will have to be incorporated from time to time into any tillage system to maintain soil conditions adequate for sustained continuous cropping. 相似文献
16.
Impacts of periodic tillage on soil C stocks: A synthesis 总被引：1，自引：1，他引：1
Richard T. Conant Mark Easter Keith Paustian Amy Swan Stephen Williams 《Soil & Tillage Research》2007,95(1-2):1-10
Long-term loss of soil C stocks under conventional tillage and accrual of soil C following adoption of no-tillage have been well documented. No-tillage use is spreading, but it is common to occasionally till within a no-till regime or to regularly alternate between till and no-till practices within a rotation of different crops. Short-term studies indicate that substantial amounts of C can be lost from the soil immediately following a tillage event, but there are few field studies that have investigated the impact of infrequent tillage on soil C stocks. How much of the C sequestered under no-tillage is likely to be lost if the soil is tilled? What are the longer-term impacts of continued infrequent no-tillage? If producers are to be compensated for sequestering C in soil following adoption of conservation tillage practices, the impacts of infrequent tillage need to be quantified. A few studies have examined the short-term impacts of tillage on soil C and several have investigated the impacts of adoption of continuous no-tillage. We present: (1) results from a modeling study carried out to address these questions more broadly than the published literature allows, (2) a review of the literature examining the short-term impacts of tillage on soil C, (3) a review of published studies on the physical impacts of tillage and (4) a synthesis of these components to assess how infrequent tillage impacts soil C stocks and how changes in tillage frequency could impact soil C stocks and C sequestration. Results indicate that soil C declines significantly following even one tillage event (1–11% of soil C lost). Longer-term losses increase as frequency of tillage increases. Model analyses indicate that cultivating and ripping are less disruptive than moldboard plowing, and soil C for those treatments average just 6% less than continuous NT compared to 27% less for CT. Most (80%) of the soil C gains of NT can be realized with NT coupled with biannual cultivating or ripping. 相似文献
17.
为探讨提高旱地麦田休闲期土壤蓄水保水能力、保证旱地小麦稳产高产的有效途径,本研究采用双因素裂区试验,主区为耕作方式(深松、深翻和旋耕),副区为保水剂施用量(0、45、90 kg·hm-2),研究了耕作方式和施用保水剂对土壤含水量、土壤养分、旱地小麦产量和水分利用率的影响,并分析了土壤含水量、生育期耗水量与旱地小麦产量及其构成因素和水分利用率之间的相关关系。结果表明,与休闲期旋耕相比,休闲期深松提高了播前20~160 cm土层的土壤含水量,休闲期深翻提高了播前0~20 cm和60~140 cm土层的土壤含水量,加速了收获期20~200 cm土层的水分利用;并通过增加穗数和穗粒数使旱地小麦产量分别提高了12.63%和6.88%,显著提高了水分利用率和降水利用率,20~40 cm土层有机质、碱解氮、速效磷含量总体提高。休闲期耕作,配施保水剂45 kg·hm-2显著提高了旱地小麦休闲期蓄水保水能力、水分利用率和产量。休闲期深松增产效果和提高水分利用率效果优于休闲期深翻。旱地小麦产量和降水利用率与播前60~120 cm土层含水量呈正相关。本研究结果为晋南旱地小麦优化耕作方式和保水剂施用量提高产量和水分利用率提供了理论依据,对旱地小麦稳产高产、减小年际间产量波动具有重要意义。 相似文献
18.
《国际水土保持研究(英文)》2014,2(1):5-13
In response to the dust bowls of the mid-thirties in the USA, soil and water conservation programmes involving reduced tillage were promoted to control land degradation, particularly soil erosion. The farming and land management practices that were considered to adequately address soil and water conservation objectives were based on no-till seeding and maintenance of soil mulch cover. This collection of practices led to what became known as conservation tillage, although no-till systems by definition avoid soil disturbance by no-till direct seeding, and maintain an organic mulch cover on the soil surface.This article is an overview of achievements in soil and water conservation on agricultural lands through the experience derived from the adoption and spread of Conservation Agriculture (CA) world-wide. CA is an agro-ecological approach to sustainable production intensification. It involves the application of three inter-linked principles that underpin agricultural production systems based on locally formulated practices: (i) permanent no or minimum mechanical soil disturbance, which in practice entails direct seeding through mulch into no-till soils; (ii) maintenance of soil cover with crop residues and green manure crops, particularly legumes; and (iii) diversified cropping system involving annuals and perennial in rotations, sequences and associations.In 2011, CA had spread over 125 million hectares (9% of the global cropped land) across all continents and most agro-ecologies, including small and large farms. In addition, there is a significant area of CA orchards in the Mediterranean countries. CA is now considered to be a practical agro-ecological approach to achieving sustainable agriculture intensification. It offers environmental, economic and social advantages that are not fully possible with tillage-based production systems, as well as improved productivity and resilience, and improved ecosystem services while minimizing the excessive use of agrochemicals, energy and heavy machinery. While there are challenges to the adoption of CA, there is also increasing interest from producers, the civil society, donors and private sector institutions to further promote and service the uptake and spread of CA globally. 相似文献
19.
《Soil & Tillage Research》1988,11(1):63-71
Field studies were conducted at 2 locations in Alabama during 1984 and 1985 to identify cultural practices which would improve cotton (Gossypium hirsutum L.) stands when plantned no-till into winter legumes. The soils were a Decatur silt loam (Rhodic Paleudult) and a Norfolk sandy loam (Typic Paleudult). The experimental design was a randomized complete block with 4 replications. Whole plots consisted of winter annual legumes (Vicia villosa Roth or Trifolium incarnatum L.) and fallow areas. Split-plot treatments established at cotton planting included conventional and conservation tillage, and fungicide. Soil samples were collected at cotton planting for population determination of Collembola and Acari species, and for estimation of cotton-disease fungus (Rhizoctonia solani) infestation. Collembola populations were greater in the Decatur than Norfolk soils, and higher in legume-mulched than fallow soils by 39 and 72% for the Decatur and Norfolk soil, respectively. Disease infestation in the Decatur soil was 10% higher in legume than fallow plots, and 18% higher in legume than fallow plots in the Norfolk soil. Cotton populations were 19% less in legume than fallow areas, and 25% less with conservation (no-till) than with standard tillage. Bedding improved cotton stands by 21% compared to conservation tillage. Seed-cotton yields from the Decatur soil were consistently high (3798 kg ha−1, and there was no yield response to treatments. Maximum seed-cotton yields at the Norfolk site were achieved with conservation tillage in the fallow area, and conventional tillage in the legume area (both receiving fungicide). 相似文献
20.
Soil degradation reduces soil productivity and is a serious problem on much of the land in semi-arid regions. To avert continued degradation, the soil productivity balance must be shifted from degrading processes to conservation practices. Crop residue management and conservation tillage are on the positive side of the balance. When adequate residues are available and conservation tillage is used, soil erosion is greatly reduced and water conservation is enhanced. Water conservation is important for improving crop yields in semi-arid regions, especially where irrigations is not used. A major constraint to residue management in many countries is low production and widespread use for other purposes. In such cases, clean tillage and appropriate support practices such as contouring, furrow diking, strip cropping and terracing may provide adequate soil and water conservation benefits. Where these are not adequate, alternative management practices should be implemented to ease the demand for residues, thus permitting more of them to be retained on the land for soil and water conservation purposes. Some alternative practices include limited or selective residue removal, substituting high quality forages for residues as animal feed, alley cropping, using wasteland areas more effectively, improving the balance between feed supplies and animal populations, and using alternative fuel sources. 相似文献