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Sample records for quantifying tillage effects

  1. A simplified modelling approach for quantifying tillage effects on soil carbon stocks

    DEFF Research Database (Denmark)

    Chatskikh, Dmitri; Hansen, Søren; Olesen, Jørgen E.

    2009-01-01

    Soil tillage has been shown to affect long-term changes in soil organic carbon (SOC) content in a number of field experiments. This paper presents a simplified approach for including effects of tillage in models of soil C turnover in the tilled-soil layer. We used an existing soil organic matter...... then compared using slopes of linear regressions of SOC changes over time. Results showed that the SOM model captured observed changes in SOC content from differences in rotations, N application and crop residue management for conventional tillage. On the basis of SOC change data a mean TF of 0.48 (standard...... deviation, SD = 0.12) was estimated for NT. The results indicate that (i) the estimated uncertainty of tillage effects on SOC turnover may be smaller than previously thought and (ii) simple scaling of SOM model parameters may be sufficient to capture the effects of soil tillage on SOM turnover in the tilled...

  2. Tillage Effects on Spatiotemporal Variability of Particulate Organic Matter

    Directory of Open Access Journals (Sweden)

    Juhwan Lee

    2009-01-01

    Full Text Available This study was performed to evaluate effects of no-till (NT and standard tillage (ST on POM in two 15-ha neighboring fields from 2003 to 2004. We also evaluated the effects of minimum tillage (MT on POM after both NT and ST fields were converted to MT in the summer of 2005. We quantified C and N stocks of three size fractions (53–250, 250–1000, and 1000–2000 μm of POM (0–0.15 m depth. The POM-C 53–250 μm and 250–1000 μm fractions decreased by 25% and 36% after six months under ST, whereas relatively little change occurred under NT, suggesting significant tillage effects over the period 2003-2004. Only small changes in POM content then occurred under MT on both fields. Changes in POM-N were similar to POM-C changes upon tillage conversions. This suggests that reduced tillage did not lead to soil C increase compared to ST but may help maintain the level of soil C for a typical California farming system. Short-term, field level variability of POM was primarily affected by tillage and was further influenced by clay content, bulk density, and scale of observation.

  3. Tillage Effects on Soil Properties & Respiration

    Science.gov (United States)

    Rusu, Teodor; Bogdan, Ileana; Moraru, Paula; Pop, Adrian; Duda, Bogdan; Cacovean, Horea; Coste, Camelia

    2015-04-01

    Soil tillage systems can be able to influence soil compaction, water dynamics, soil temperature and soil structural condition. These processes can be expressed as changes of soil microbiological activity, soil respiration and sustainability of agriculture. Objectives of this study were: 1) to assess the effects of tillage systems (Conventional System-CS, Minimum Tillage-MT, No-Tillage-NT) on soil compaction, soil temperature, soil moisture and soil respiration and 2) to establish the relationship that exists in changing soil properties. Three treatments were installed: CS-plough + disc; MT-paraplow + rotary grape; NT-direct sowing. The study was conducted on an Argic-Stagnic Faeoziom. The MT and NT applications reduce or completely eliminate the soil mobilization, due to this, soil is compacted in the first year of application. The degree of compaction is directly related to soil type and its state of degradation. The state of soil compaction diminished over time, tending toward a specific type of soil density. Soil moisture was higher in NT and MT at the time of sowing and in the early stages of vegetation and differences diminished over time. Moisture determinations showed statistically significant differences. The MT and NT applications reduced the thermal amplitude in the first 15 cm of soil depth and increased the soil temperature by 0.5-2.20C. The determinations confirm the effect of soil tillage system on soil respiration; the daily average was lower at NT (315-1914 mmoli m-2s-1) and followed by MT (318-2395 mmoli m-2s-1) and is higher in the CS (321-2480 mmol m-2s-1). Comparing with CS, all the two conservation tillage measures decreased soil respiration, with the best effects of no-tillage. An exceeding amount of CO2 produced in the soil and released into the atmosphere, resulting from aerobic processes of mineralization of organic matter (excessive loosening) is considered to be not only a way of increasing the CO2 in the atmosphere, but also a loss of

  4. Micro and macroscopic investigation to quantify tillage impact on soil hydrodynamic behaviour

    Science.gov (United States)

    Beckers, E.; Roisin, C.; Plougonven, E.; Deraedt, D.; Léonard, A.; Degré, A.

    2012-04-01

    Nowadays, tillage simplification is an increasing practice. Many advantages are cited in the literature, such as energy saving, soil conservation etc. Agricultural management practices influence soil structure, but consequent changes in soil hydrodynamic behaviour at the field scale are still not well understood. Many studies focus only on macroscopic measurements which do not provide mechanistic explanations. Moreover, research shows divergent conclusions over structure modification. The aim of this work is to fill this gap by quantifying soil structure modification depending on tillage intensity through both macroscopic and microscopic measurements, the latter improving our comprehension of the fundamental mechanisms involved. Our experiment takes place in Gentinnes (Walloon Brabant, Belgium), on a field organized in a Latin square scheme. Since 2004, plots have been cultivated in conventional tillage (CT) or in reduced tillage (RT). The latter consists in sowing after stubble ploughing of about 10cm. The crop rotation is sugar beet followed by winter wheat. The soil is mainly composed of silt loam and can be classified as a Luvisol. Macroscopic investigations consist in establishing pF and K(h) curves and 3D soil strength profiles. At the microscale, 3D morphologic parameters are measured using X-ray microtomography. Because of the variation of working depth between management practices (10cm for RT vs. 25cm for CT), two horizons were investigated: H1 between 0-10cm and H2 between 12-25cm. 3D soil strength profiles were established thanks to a fully automated penetrometer (30° angle cone with a base area of 10mm2) which covered a 160 × 80cm2 area with 5cm spacing between neighbouring points. At each node, penetration was performed and soil strength measurements were collected every 1cm from 5 to 55cm depth. K(h) curves were provided by 20cm diameter tension-infiltrometer measurements (Eijkelkamp Agrisearch Equipment). Undisturbed soil samples were removed from

  5. Tillage System and Cover Crop Effects on Soil Quality

    DEFF Research Database (Denmark)

    Abdollahi, Lotfollah; Munkholm, Lars Juhl

    2014-01-01

    Information about the quantitative effect of conservation tillage combined with a cover crop on soil structure is still limited. This study examined the effect of these management practices on soil pore characteristics of a sandy loam soil in a long-term field trial. The tillage treatments (main...

  6. The Effect of Conservation Tillage and Cover Crop Residue on Beneficial Arthropods and Weed Seed Predation in Acorn Squash.

    Science.gov (United States)

    Quinn, N F; Brainard, D C; Szendrei, Z

    2016-12-01

    Conservation tillage combined with cover crops or mulching may enhance natural enemy activity in agroecosystems by reducing soil disturbance and increasing habitat structural complexity. In particular, weed seed predation can increase with vegetation cover and reduced tillage, indicating that mulches may improve the quality of the habitat for weed seed foraging. The purpose of this study was to quantify the effects of tillage and mulching for conservation biological control in cucurbit fields. The effects of mulch and reduced tillage on arthropods and rates of weed seed loss from arenas were examined in field trials on sandy soils in 2014 and 2015. Experimental factors included tillage and cover crop, each with two levels: strip-tillage or full-tillage, and cover crop mulch (rye residue) or no cover crop mulch (unmulched). Arthropod abundance on the crop foliage was not affected by tillage or cover crops. Contrary to expectations, epigeal natural enemies of insects and rates of weed seed removal either did not respond to treatments or were greater in full-tilled plots and plots without mulch. Our study demonstrates the potential importance of weed seed predators in reducing weed seedbanks in vegetable agroecosystems, and suggests that early-season tillage may not be detrimental to epigeal predator assemblages. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Fall and spring tillage effects on sugarbeet production

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    The ability to vary primary tillage timing between fall and spring for sugarbeet production could benefit producers by providing flexibility for when field work occurs and may allow earlier planting in the spring. This study was conducted to evaluate the effects of strip and conventional tillage co...

  8. [Effects of different tillage methods on tea garden soil physical characteristics and tea yield].

    Science.gov (United States)

    Su, You-jian; Wang, Ye-jun; Zhang, Yong-li; Ding, Yong; Luo, Yi; Song, Li; Liao, Wan-you

    2015-12-01

    The effects of three tillage methods, i.e., no tillage, rotary tillage, deep tillage, on tea garden soil compaction, soil moisture, soil bulk density, yield component factors and tea yield were studied through field experiments in Langxi Country of Anhui Province. The results indicated that the effects of three tillage methods on soil bulk density and soil compaction were in order of deep tillage>rotary tillage>no tillage. Deep tillage and rotary tillage could effectively break the argillic horizon layer and decrease the soil compaction. Compared with no tillage, soil compaction and soil bulk density (0-30 cm) under deep tillage decreased 16.4% and 13.4%-27.5%, respectively. Deep tillage could significantly increase soil water storage space and enhance the water holding capacity of the soil. Compared with no tillage, the soil moisture of 15-30 cm soil layer was increased by 7.7% under deep tillage. The different tillage methods had little effect on soil porosity. Rotary tillage and deep tillage could increase soil specific surface area and the ratios of soil gas and soil liquid. The diurnal changes of photosynthetic rate and transpiration rate of tea both exhibited double-peak pattern. There was a significant midday depression caused principally by stomatal factors. Under deep tillage, the tea leaf transpiration rate decreased, shoot density increased, 100-bud dry mass and water use efficiency increased significantly, and the tea yield increased by 17.6% and 6.8% compared with no tillage and rotary tillage, respectively. Deep tillage was the most appropriate tillage practice in tea garden of east Anhui Province.

  9. Effects of Tillage Practices on Soil Organic Carbon and Soil Respiration

    Science.gov (United States)

    Rusu, Teodor; Ioana Moraru, Paula; Bogdan, Ileana; Ioan Pop, Adrian

    2016-04-01

    Soil tillage system and its intensity modify by direct and indirect action soil temperature, moisture, bulk density, porosity, penetration resistance and soil structural condition. Minimum tillage and no-tillage application reduce or completely eliminate the soil mobilization, due to this, soil is compacted in the first years of application. The degree of compaction is directly related to soil type and its state of degradation. All this physicochemical changes affect soil biology and soil respiration. Soil respiration leads to CO2 emissions from soil to the atmosphere, in significant amounts for the global carbon cycle. Soil respiration is one measure of biological activity and decomposition. Soil capacity to produce CO2 varies depending on soil, season, intensity and quality of agrotechnical tillage, soil water, cultivated plant and fertilizer. Our research follows the effects of the three tillage systems: conventional system, minimum tillage and no-tillage on soil respiration and finally on soil organic carbon on rotation soybean - wheat - maize, obtained on an Argic Faeoziom from the Somes Plateau, Romania. To quantify the change in soil respiration under different tillage practices, determinations were made for each crop in four vegetative stages (spring, 5-6 leaves, bean forming, harvest). Soil monitoring system of CO2 and O2 included gradient method, made by using a new generation of sensors capable of measuring CO2 concentration in-situ and quasi-instantaneous in gaseous phase. At surface soil respiration is made by using ACE Automated Soil CO2 Exchange System. These areas were was our research presents a medium multi annual temperature of 8.20C medium of multi annual rain drowns: 613 mm. The experimental variants chosen were: i). Conventional system: reversible plough (22-25 cm) + rotary grape (8-10 cm); ii). Minimum tillage system: paraplow (18-22 cm) + rotary grape (8-10 cm); iii). No-tillage. The experimental design was a split-plot design with three

  10. Effects of tillage practices and carbofuran exposure on small mammals

    Science.gov (United States)

    Albers, P.H.; Linder, G.; Nichols, J.D.

    1990-01-01

    We compared population estimates, body mass, movement, and blood chemistry of small mammals between conventionally tilled and no-till cornfields in Maryland and Pennsylvania to evaluate the effects of tillage practices and carbofuran exposure on small mammals.

  11. Modeling Edge Effects of Tillage Erosion

    Science.gov (United States)

    Tillage erosion has been recognized as an important factor in redistribution of soil over time and in the development of morphological changes within agricultural fields. Field borders, fences, and vegetated strips that interrupt soil fluxes lead to the creation topographic discontinuities or lynche...

  12. Effects of Tillage Management Systems on Residue Cover and Decomposition

    Institute of Scientific and Technical Information of China (English)

    ZHANGZHIGUO; XUQI; 等

    1998-01-01

    The effects of tillage methods on percent surface residue cover remaining and decomposition rates of crop residues were evaluated in this study.The line transect method was used to measure residue cover percentage on continuumous corn(Zea mays L.) plots under no tillage (NT),Conventional tillage(CT),chisel plow(CH),and disk tillage (DT).Samples of rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) were used for residue decompostion study,Results showed that the percentage of residue cover remaining was significantly higher for NT than for CH and DT and that for CT was the lowest(<10%),For the same tillage system ,the percent residue cover remaining was significantly higher in the higher fertilizer N rate treatments relative to the lower fertilizer N treatments.weight losses of rye and vetch residues followed a similar pattern under CT and DT ,and they were significantly faster in CT and DT than in NT system ,Alo ,the amounts of residue N remaining during the first 16 weeks were alway higher under NT than under CT and DT.

  13. Short-term effects of tillage on mineralization of nitrogen and carbon in soil

    OpenAIRE

    Hanne L. Kristensen; Debosz, Kasia; McCarty, Greg W.

    2003-01-01

    Tillage is known to decrease soil organic nitrogen (N) and carbon (C) pools with negative consequences for soil quality. This decrease is thought partly to be caused by exposure of protected organic matter to microbial degradation by the disturbance of soil structure. Little is known, however, about the short-term effects of tillage on mineralization of N and C, and microbial activity. We studied the short-term effects of two types of tillage (conventional plough- and a non-inverting-tillage)...

  14. The Effect on Soil Erosion of Different Tillage Applications

    Science.gov (United States)

    Gür, Kazım

    2016-04-01

    The Effects on Soil Erosion of Different Tillage Applications Kazım Gür1, Kazim Çarman2 and Wim M.Cornelis3 1Bahri Daǧdaş International Agricultural Research Instıtute, 42020 Konya, Turkey 2Faculty of Agriculture, Department of Agricultural Machinery, University of Selçuk, 42031 Konya, Turkey 3Department of Soil Management, Faculty of Bioscience Engineering, Ghent University, 653 Coupure Links, 9000 Gent, Belgium Traditional soil cultivation systems, with excessive and inappropriate soil tillage, will generally lead to soil degradation and loss of soil by wind erosion. Continuous reduced tillage and no-till maintaining soil cover with plant residues called Conservation Agriculture that is considered as effective in reducing erosion. There exist a wide variety of practices using different tools that comply with reduced tillage principles. However, few studies have compared the effect of several of such tools in reducing wind erosion and related soil and surface properties. We therefore measured sediment transport rates over bare soil surfaces (but with under stubbles of wheat, Triticum aestivum L.) subjected to three tillage practices using two pulling type machines and one type of power takeoff movable machines and generated with a portable field wind tunnel. At 10 ms-1, sediment transport rates varied from 107 to 573 gm-1h-1, and from 176 to 768 gm-1h-1 at 13 ms-1. The lowest transport rates were observed for N(no-tillage) and the highest for Rr(L-type rototiller). After tillage, surface roughness, mean weighted diameter, wind erodible fraction, mechanical stability and soil water content were measured as well and varied from 5.0 to 15.9%, 6.9 to 13.8 mm, 14.3 to 29.7%, 79.5 to 93.4% and 8.6 to 15.1%, respectively, with again N is being the most successful practice. In terms of conservation soil tillage technique, it can be said that the applications compared with each other; direct sowing machine is more appropriate and cause to the less erosion.

  15. Pesticide Interactions with N source and Tillage: Effects on soil biota and ecosystem services

    DEFF Research Database (Denmark)

    Jensen, John; Petersen, Søren O; Elsgaard, Lars;

    Pesticide effects on soil biota must be interpreted in the context of the specific management practice, including rotation, fertilization, tillage, and pest control. Tillage, foe example, has been shown to reduce earthworm populations by up to 80%, depending on timing and specific tillage technique...

  16. Effects of tillage systems on yield of cotton following canola in Gorgan

    Directory of Open Access Journals (Sweden)

    F. Ghaderi- Far

    2012-04-01

    Full Text Available The conservation system is one of the proper methods avoiding the loss of nutrients, soil erosion, and reduce production costs. This research was examined for studying the influences of tillage systems on the three cotton cultivars at Karkandeh and Hashm-Abad stations in Gorgan. The experiments were conducted in a randomized completely block design as split plot with three replications with five tillage systems (Mould board plough, Chisel, Disc, Strip and no tillage as main plot and three cultivars (Siokra324, Zodrac-Motagenez and Cindoz 80 as sup-plot. The results showed that effects of tillage system was significant on yield. Yield was more in chisel and disk (Conservation tillage by having more monopodial branch length, number of monopodial and sympodial branch, plant height and boll in plant than Mould board plough (conventional tillage and no-tillage system in all cultivars. The Siokra324 cultivar had more yield due to having more boll in plant than two other cultivars. Yield in no-tillage system was lower than conservation and conventional tillage but the grown plants in this system were smaller and had lower branching. Thus population density can be increased for gaining higher yield from this system, and it is recommended to do complete experiments for studying the effects of various population densities in no tillage system and conservation tillage with the conclusive studies are replaced conventional tillage.

  17. Tillage effects on topsoil structural quality assessed using X-ray CT, soil cores and visual soil evaluation

    DEFF Research Database (Denmark)

    Garbout, Amin; Munkholm, Lars Juhl; Hansen, Søren Baarsgaard

    2013-01-01

    Soil structure plays a key role in the ability of soil to fulfil essential functions and services in relation to, e.g., root growth, gas and water transport and organic matter turnover. The objective of this paper was: (1) To quantify tillage effects on soil structural quality in the entire topsoil...

  18. Potential effect of conservation tillage on sustainable land use : a review of global long-term studies

    NARCIS (Netherlands)

    Wang Xiaobin,; Cai, D.; Hoogmoed, W.B.; Oenema, O.; Perdok, U.D.

    2006-01-01

    Although understood differently in different parts of the world, conservation tillage usually includes leaving crop residues on the soil surface to reduce tillage. Through a global review of long-term conservation tillage research, this paper discusses the long-term effect of conservation tillage on

  19. EFFECTS OF DIFFERENT SOIL TILLAGE SYSTEMS ON NODULATION AND YIELD OF SOYBEAN

    Directory of Open Access Journals (Sweden)

    D. Jug

    2005-12-01

    Full Text Available The primary soil tillage for different crops in Croatia is generally based on mouldboard ploughing which is the most expensive for crops production. Negative effects due to frequent passes by equipment and machines (deterioration of soil structure, soil compaction, lower biogenity and soil tilth, together with negative economical and energetical costs, can be lowered and avoided by introduction of reduced soil tillage or direct drilling (No-tillage. Accordingly, the main goal of this research was to determine effects of conventional and reduced soil tillage systems on yield components and nodulation ability of nitrogen fixing bacteria in soybean crop. The research was established at chernozem soil type of northern Baranja as monofactorial completely randomized block design in four repetitions. The soil tillage variants were as follows: CT Conventional Tillage (primary soil tillage by moldboard ploughing at 25-30 cm depth, DH Multiple Diskharrowing at 10-15 cm as primary tillage, and NT No-tillage system. Results show significantly lower plant density, mass of 1000 grains and grain yield at variants with reduced soil tillage in both investigation years. However, reduced tillage systems had positive trend on nitrogen-fixing bacteria nodulation, since the highest values of number and mass of nodules per plant were recorded. This research was run during the years 2002 and 2003, the last one extremely droughty, thus it requires continuation.

  20. [Effects of tillage methods on soil physicochemical properties and biological characteristics in farmland: A review].

    Science.gov (United States)

    Li, Yu-jie; Wang, Hui; Zhao, Jian-ning; Huangfu, Chao-he; Yang, Dian-lin

    2015-03-01

    Tillage methods affect soil heat, water, nutrients and soil biology in different ways. Reasonable soil management system can not only improve physical and chemical properties of the soil, but also change the ecological process of farmland soil. Conservation tillage can improve the quality of the soil to different degrees. For example, no-tillage system can effectively improve soil enzyme activity. No tillage and subsoiling tillage can provide abundant resources for soil microbe' s growth and reproduction. No tillage, minimum tillage and other conservation tillage methods exert little disturbance to soil animals, and in turn affect the quantity and diversity of the soil animals as well as their population structure. Effects of different tillage methods on soil physical and chemical properties as well as biological characteristics were reviewed in this article, with the soil physical and chemical indices, enzyme activities, soil microbe diversity and soil animals under different tillage patterns analyzed. The possibility of soil quality restoration with appropriate tillage methods and the future research direction were pointed out.

  1. [Effects of conservation tillage and weed control on soil water and organic carbon contents in winter wheat field].

    Science.gov (United States)

    Han, Hui-Fang; Ning, Tang-Yuan; Li, Zeng-Jia; Tian, Shen-Zhong; Wang, Yu; Zhong, Wei-Lei; Tian, Xin-Xin

    2011-05-01

    Taking a long-term (since 2004) straw-returning winter wheat field as the object, an investigation was made in the wheat growth seasons of 2008-2009 and 2009-2010 to study the effects of different tillage methods (rotary tillage, harrow tillage, no-tillage, subsoil tillage, and conventional tillage) and weed management on the soil water and organic carbon contents. No matter retaining or removing weeds, the weed density under subsoil tillage and no-tillage was much higher than that under rotary tillage, harrow tillage, and conventional tillage. From the jointing to the milking stage of winter wheat, retaining definite amounts of weeds, no matter which tillage method was adopted, could significantly increase the 0-20 cm soil water content, suggesting the soil water conservation effect of retaining weeds. Retaining weeds only increased the soil organic carbon content in 0-20 cm layer at jointing stage. At heading and milking stages, the soil organic carbon contents in 0-20, 20-40, and 40-60 cm layers were lower under weed retaining than under weed removal. Under the conditions of weed removal, the grain yield under subsoil tillage increased significantly, compared with that under the other four tillage methods. Under the conditions of weed retaining, the grain yield was the highest under rotary tillage, and the lowest under conventional tillage.

  2. Tillage System and Cover Crop Effects on Soil Quality

    DEFF Research Database (Denmark)

    Abdollahi, Lotfollah; Munkholm, Lars Juhl

    2014-01-01

    Optimal use of management systems including tillage and winter cover crops is recommended to improve soil quality and sustain agricultural production. The effects on soil properties of three tillage systems (as main plot) including direct drilling (D), harrowing to a depth of 8 to 10 cm (H......), and moldboard plowing (MP) with and without a cover crop were evaluated in a long-term experiment on a sandy loam soil in Denmark. Chemical, physical, and biological soil properties were measured in the spring of 2012. The field measurements included mean weight diameter (MWD) after the drop-shatter test......, penetration resistance, and visual evaluation of soil structure (VESS). In the laboratory, aggregate strength, water-stable aggregates (WSA), and clay dispersibility were measured. The analyzed chemical and biological properties included soil organic C (SOC), total N, microbial biomass C, labile P and K...

  3. [Effects of different tillage measures on upland soil respiration in Loess Plateau].

    Science.gov (United States)

    Sun, Xiao-hua; Zhang, Ren-zhi; Cai, Li-qun; Chen, Qiang-qiang

    2009-09-01

    A field experiment was conducted in Lijiabu Town of Dingxi City, Gansu Province to study the soil respiration and its relations with the canopy temperature and soil moisture content in a rotation system with spring wheat and pea under effects of different tillage measures. Six treatments were installed, i.e., tillage with no straw- or plastic mulch (conventional tillage, T), tillage with straw mulch (TS), tillage with plastic mulch (TP), no-tillage (NT), no-tillage with straw mulch (NTS), and no-tillage with plastic mulch (NTP). During the growth periods of spring wheat and pea, soil respiration had different change patterns, with the peaks appeared at the early jointing, grain-filling, and maturing stages of spring wheat, and at the 5-leaf, silking, flowering and poding, in spring wheat field between treatments NTS and T, and the soil respiration rate was significantlyand maturing stages of pea. There was an obvious difference in the diurnal change of soil respiration lower in NTS than in T; while the soil respiration in pea field had less diurnal chan ge. Soil respiration rate had a significant linear relationship with the canopy temperature of both spring wheat andpea, the correlation coefficient being the highest at booting stage of spring wheat and at flowering and poding stage of pea, followed by at grain-filling stage of spring wheat and at branching stage of pea. There was also a significant parabola relationship between soil respiration rate and soil moisture content, the correlation coefficient being higher under conservation tillage than under conventional tillage, with the highest under NTS. The moisture content in 10-30 cm soil layer of spring wheat field and that in 5-10 cm soil layer of pea field had the greatest effects on soil respiration. Comparing with conventional tillage, all the five conservation tillage measures decreased soil respiration, with the best effects of no-tillage with straw mulch.

  4. [Effects of Tillage on Soil Respiration and Root Respiration Under Rain-Fed Summer Corn Field].

    Science.gov (United States)

    Lu, Xing-li; Liao, Yun-cheng

    2015-06-01

    To explore the effects of different tillage systems on soil respiration and root respiration under rain-fed condition. Based on a short-term experiment, this paper investigated soil respiration in summer corn growth season under four tillage treatments including subsoiling tillage (ST), no tillage (NT), rotary tillage (RT) and moldboard plow tillage (CT). The contribution of root respiration using root exclusion method was also discussed. The results showed that soil respiration rate presented a single peak trend under four tillage methods during the summer corn growing season, and the maximum value was recorded at the heading stage. The trends of soil respiration were as follows: heading stage > flowering stage > grain filling stage > maturity stage > jointing stage > seedling stage. The trends of soil respiration under different tillage systems were as follows: CT > ST > RT > NT. There was a significant correlation between soil respiration rate and soil temperatures (P tillage systems. Therefore, root exclusion method could be used to study the contribution of crop growth to carbon emission, to compare effects of different tillage systems on the contribution of root respiration provides the bases for selecting the measures to slow down the decomposition of soil carbon.

  5. [Effects of returning straw to soil and different tillage methods on paddy field soil fertility and microbial population].

    Science.gov (United States)

    Ren, Wan-Jun; Liu, Dai-Yin; Wu, Jin-Xiu; Wu, Ju-Xian; De, Chen-Chun; Yang, Wen-Yu

    2009-04-01

    A field experiment was conducted on a paddy field to study the effects of returning straw to soil and different tillage methods (no-tillage + returning straw, no-tillage, tillage + returning straw, and tillage) on the fertility level and microbial quantities of different soil layers. The results showed that in upper soil layer, the organic matter content in treatment 'no-tillage + returning straw' was 5.33, 2.79, and 5.37 g x kg(-1) higher than that in treatments 'no-tillage', 'tillage + returning straw', and 'tillage', respectively, and the contents of total and available N, P and K in treatment 'no-tillage + returning straw' were also the highest, followed by in treatments 'no-tillage' and 'tillage + returning straw', and in treatment 'tillage'. In deeper soil layer, all the fertility indices were higher in treatment 'tillage + returning straw'. Treatments of 'returning straw to soil' had the highest quantities of soil microbes. The quantities of bacteria, fungi, and actinomycetes in upper soil layer were the highest in treatment 'no-tillage + returning straw', and thus, the cellulose decomposition intensity in this treatment at maturity period was 26.44%, 79.01%, and 98. 15% higher than that in treatments 'tillage + returning straw', 'no-tillage', and 'tillage', respectively. In deeper soil layer, the quantities of bacteria, fungi, and actinomycetes were the highest in treatment 'tillage + returning straw'. Treatment 'no-tillage + returning straw' had the features of high fertility and abundant microbes in surface soil layer. The quantities of soil bacteria and actinomycetes and the decomposition intensity of soil cellulose were significantly positively correlated with soil fertility level.

  6. Effects of Secondary Tillage Implement on Some Properties of Soil and Yield of Sunflower

    Directory of Open Access Journals (Sweden)

    Y. Bayhan

    2007-01-01

    Full Text Available In this study, field cultivator (FC, disk harrow (HD, combination of cultivator with spring teeth and rotary harrow (CS+RH were used as secondary tillage equipment in spring. Physical properties of soil such as bulk density, porosity, mean weight diameter and aggregate stability were determined before and after tillage. Moreover, effect of different seedbed preparation techniques on yield of sunflower was also investigated.In the result of the study, differentiations among the secondary tillage equipment were observed due to bulk density and porosity. Small sized aggregates (1-5mm were highly in tillage with combination of cultivator with spring teeth and rotary harrow. While the mean weight diameter, which shows the durability of aggregates to water, was 2.83 mm before tillage, it was 3.96 mm in tillage with DH, 1.80 mm in tillage with FC and 2.50 mm in tillage with combination equipment. Although the mean weight diameter in tillage with DH increased, decreased in tillage with FC. The best aggregate stability obtained from seedbed preparation by disc harrow. On the other hand field cultivator is the most affective soil embossing tool while the cultivator with spring teeth rotary harrow combination is smashing.The yield values were found 2.002 Mg ha-1 with DH, 2.106 Mg ha-1 with FC, 2.175 Mg ha-1 with CS+RH.

  7. Effects of deep tillage and straw returning on soil microorganism and enzyme activities.

    Science.gov (United States)

    Ji, Baoyi; Hu, Hao; Zhao, Yali; Mu, Xinyuan; Liu, Kui; Li, Chaohai

    2014-01-01

    Two field experiments were conducted for two years with the aim of studying the effects of deep tillage and straw returning on soil microorganism and enzyme activity in clay and loam soil. Three treatments, (1) conventional tillage (CT), shallow tillage and straw returning; (2) deep tillage (DT), deep tillage and straw returning; and (3) deep tillage with no straw returning (DNT), were carried out in clay and loam soil. The results showed that deep tillage and straw returning increased the abundance of soil microorganism and most enzyme activities. Deep tillage was more effective for increasing enzyme activities in clay, while straw returning was more effective in loam. Soil microorganism abundance and most enzyme activities decreased with the increase of soil depth. Deep tillage mainly affected soil enzyme activities in loam at the soil depth of 20-30 cm and in clay at the depth of 0-40 cm. Straw returning mainly affected soil microorganism and enzyme activities at the depths of 0-30 cm and 0-40 cm, respectively.

  8. [Effects of conservation tillage on the composition of soil exchangeable base].

    Science.gov (United States)

    Hu, Ning; Lou, Yi-Lai; Zhang, Xiao-Ke; Liang, Wen-Ju; Liang, Lei

    2010-06-01

    Taking the soil in Zhangwu County of Liaoning Province as test object, a comparative study was made to understand the composition of soil exchangeable base under traditional tillage and 6-year conservation tillage (no-tillage plus straw mulch). Comparing with traditional tillage, conservation tillage increased the total amount of exchangeable base (SEB) and the contents of exchangeable K, Ca, and Mg in top (0-15 cm) soil, suggesting its positive effect in increasing soil nutrient holding capacity and buffering ability. This effect had a close relationship with the changes of soil organic matter and clay contents, according to correlation analysis. In addition, the K/SEB and Ca/Mg ratios were higher, while the (Ca+Mg)/SEB, Ca/K, and Mg/K ratios were lower under conservation tillage than under traditional tillage, illustrating that the effects of conservation tillage on soil exchangeable base were mainly presented in the relative enrichment of soil exchangeable Ca and K, especially K. Conservation tillage increased the stratification ratio (0-5 cm/5-15 cm and 0-5 cm/15-30 cm) of soil exchangeable K, Ca, and Mg, and SEB, suggesting the increase of the vertical variability of SEB in plough layer.

  9. Effects of crop rotation, tillage, and fertilizer applications on sorghum head insects.

    Science.gov (United States)

    Chilcutt, Charles F; Matocha, John E

    2007-02-01

    Rotations, tillage, and fertilizer treatments can affect yield, costs, and profitability in sorghum, Sorghum bicolor (L.) Moench, depending on their effects on pests. Rotation or planting different crops reduces soil erosion and pests that build up when a field is planted to the same crop each year. Minimum tillage reduces the number of trips over a field, lessening soil compaction and reducing costs. We examined the effects of fertilizer, tillage, and rotation with cotton, Gossypium hirsutum L., on sorghum head insects during three sampling periods each year from 2000 to 2003. We found that fertilizer treatments did not affect pests or predators. Also, predators were unaffected by rotation and tillage, which some years affected Helicoverpa zea (Boddie) and Oebalus pugnax (F.), both pests that feed on developing sorghum kernels, thereby reducing yield. In 2000, H. zea densities were greater in continuous sorghum, regardless of tillage practice, than in sorghum-cotton rotation. However, in 2003, H. zea densities were greater in minimum tillage plots within sorghum- cotton rotation than minimum tillage plots within continuous sorghum. In 2000, in sorghum- cotton rotation, O. pugnax densities were greater in minimum tillage than conventional tillage plots, whereas in continuous sorghum the opposite was true, O. pugnax were greater in conventional tillage. Also, O. pugnax were greater in sorghum- cotton rotation than in continuous sorghum. In 2002, O. pugnax densities were greater in conventional than minimum tillage plots. These results suggest that rotation of sorghum with cotton can sometimes reduce H. zea, but this reduction may occur with increased density of O. pugnax. Also, reducing tillage may reduce O. pugnax in some instances.

  10. Effect of Interplanting with Zero Tillage and Straw Manure on Rice Growth and Rice Quality

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The interplanting with zero-tillage of rice, i.e. directsowing rice 10-20 days before wheat harvesting, and remaining about 30-cm high stubble after cutting wheat or rice with no tillage, is a new cultivation technology in wheat-rice rotation system. To study the effects of interplanting with zero tillage and straw manure on rice growth and quality, an experiment was conducted in a wheat-rotation rotation system. Four treatments, i.e. ZIS (Zero-tillage, straw manure and rice interplanting), ZI (Zero-tillage, no straw manure and rice interplanting), PTS (Plowing tillage, straw manure and rice transplanting), and PT (Plowing tillage, no straw manure and rice transplanting), were used. ZIS reduced plant height, leaf area per plant and the biomass of rice plants, but the biomass accumulation of rice at the late stage was quicker than that under conventional transplanting cultivation. In the first year (2002), there was no significant difference in rice yield among the four treatments. However, rice yield decreased in interplanting with zero-tillage in the second year (2003). Compared with the transplanting treatments, the number of filled grains per panicle decreased but 1000-grain weight increased in interplanting with zero-tillage, which were the main factors resulting in higher yield. Interplanting with zero-tillage improved the milling and appearance qualities of rice. The rates of milled and head rice increased while chalky rice rate and chalkiness decreased in interplanting with zero-tillage. Zero-tillage and interplanting also affected rice nutritional and cooking qualities. In 2002, ZIS showed raised protein content, decreased amylose content, softer gel consistency, resulting in improved rice quality. In 2003, zero-tillage and interplanting decreased protein content and showed similar amylose content as compared with transplanting treatments. Moreover, protein content in PTS was obviously increased in comparison with the other three treatments. The rice in

  11. Potential Effect of Conservation Tillage on Sustainable Land Use: A Review of Global Long-Term Studies

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-Bin; CAI Dian-Xiong; W. B. HOOGMOED; O. OENEMA; U. D. PERDOK

    2006-01-01

    Although understood differently in different parts of the world, conservation tillage usually includes leaving crop residues on the soil surface to reduce tillage. Through a global review of long-term conservation tillage research, this paper discusses the long-term effect of conservation tillage on sustainable land use, nutrient availability and crop yield response. Research has shown several potential benefits associated with conservation tillage, such as potential carbon sequestration, nutrient availability, and yield response. This research would provide a better perspective of the role of soil conservation tillage and hold promise in promoting application of practical technologies for dryland farming systems in China.

  12. Effect of no-tillage and tillage on the ecology of mite, Acarina (Oribatida) in two different farming systems of paddy field in Cachar district of Assam.

    Science.gov (United States)

    Singh, Leimapokpam Amarjit; Ray, D C

    2015-01-01

    The present investigation was carried out in Cachar district of Assam over a period of one year (January 2011 - December 2011) to understand the seasonal ecology of Acarina (Oribatida) in rice (Oryza sativa L.) cultivated fields. Population of Oribatida was found to be maximum during August 2011, both in no-tillage (6.32 ± 0.66 No./m2 x 100(2)) and tillage (5.30 ± 0.71 No./M2 x 100(2)) sites in Dorgakona area whereas the peak was recorded during August 2011, both in no-tillage (5.38 ± 0.75 No./m(2) x 100(2)) and tillage (4.69 ± 0.77 No./m2 x 100(2)) in Durby area of study sites. Least population was encountered during January 2011, in both no-tillage (0.98 ± 0.28 ± No./m2 x 100(2)) and tillage (0.98 ± 0.30 No/m2 x 100(2)) sites in Dorgakona area whereas the same was found during November 2011 in no-tillage (0.57 ± 0.31 No.m/2 x 100(2)) and in February 2011 in tillage (0.45 ± 0.21 No./m2 x 100(2)) sites of Durby area. Linear regression analysis with all the environmental variables showed positive and significant influence on the population dynamics whereas relative humidity (R2 = 0.26 p > 0.05) in Dorgakona no-tillage and tillage (R2 = 0.19 P > 0.05) sites and relative humidity in tillage site (R2 = 0.27 P > 0.05) in Durby area showed no influence. Multiple regression analysis showed that the combined effect of climatic variables having a significant influence (p tillage and tillage systems in both the study sites. Rainfall, relative humidity and temperature facilitated the soil moisture, microbial activity and litter decomposition, which in turn may favour the reproduction and growth rate of the species. Among microclimatic conditions all the parameters showed positive and significant influence (P tillage and tillage system on both the sites except pH which showed negative correlation with the population. One way ANOVA revealed significant difference (F = 6.53, P < 0.01) of the Oribatid population between the systems.

  13. EFFECT OF SOIL TILLAGE AND PLANT RESIDUE ON SURFACE ROUGHNESS OF AN OXISOL UNDER SIMULATED RAIN

    Directory of Open Access Journals (Sweden)

    Elói Panachuki

    2015-02-01

    Full Text Available Surface roughness of the soil is formed by mechanical tillage and is also influenced by the kind and amount of plant residue, among other factors. Its persistence over time mainly depends on the fundamental characteristics of rain and soil type. However, few studies have been developed to evaluate these factors in Latossolos (Oxisols. In this study, we evaluated the effect of soil tillage and of amounts of plant residue on surface roughness of an Oxisol under simulated rain. Treatments consisted of the combination of the tillage systems of no-tillage (NT, conventional tillage (CT, and minimum tillage (MT with rates of plant residue of 0, 1, and 2 Mg ha-1 of oats (Avena strigosa Schreb and 0, 3, and 6 Mg ha-1 of maize (Zea mays L.. Seven simulated rains were applied on each experimental plot, with intensity of 60±2 mm h-1 and duration of 1 h at weekly intervals. The values of the random roughness index ranged from 2.94 to 17.71 mm in oats, and from 5.91 to 20.37 mm in maize, showing that CT and MT are effective in increasing soil surface roughness. It was seen that soil tillage operations carried out with the chisel plow and the leveling disk harrow are more effective in increasing soil roughness than those carried out with the heavy disk harrow and leveling disk harrow. The roughness index of the soil surface decreases exponentially with the increase in the rainfall volume applied under conditions of no tillage without soil cover, conventional tillage, and minimum tillage. The oat and maize crop residue present on the soil surface is effective in maintaining the roughness of the soil surface under no-tillage.

  14. Tillage and crop rotation effects on soil quality in two Iowa fields

    Science.gov (United States)

    Soil quality is affected by inherent (parent material, climate, and topography) and anthropogenic (tillage and crop rotation) factors. We evaluated effects of five tillage treatments on 23 potential soil quality indicators after 31 years in a corn (Zea mays L.)/soybean [Glycine max (L.) Merr.] rotat...

  15. The effect of different tillage and cover crops on soil quality

    DEFF Research Database (Denmark)

    Abdollahi, Lotfollah; Munkholm, Lars Juhl

    This paper examines the effect of different tillage treatments and cover crop on soil physical, chemical and biological properties of a sandy loam soil in a long-term field trial set up in 2007 at Foulum, Denmark. The experimental design is a split plot design with different tillage practices...

  16. Sustainable semiarid dryland production in relation to tillage effects on Hydrology: 1983-2013

    Science.gov (United States)

    Semiarid dryland crop yields with no-till, NT, residue management are often greater than stubble-mulch tillage, SM, as a result of improved soil conditions or water conservation, but knowledge of long-term tillage effects on the comprehensive field hydrology and sustained crop production is needed. ...

  17. Tillage effects on N2O emissions as influenced by a winter cover crop

    DEFF Research Database (Denmark)

    Petersen, Søren O; Mutegi, James; Hansen, Elly Møller

    2011-01-01

    Conservation tillage practices are widely used to protect against soil erosion and soil C losses, whereas winter cover crops are used mainly to protect against N losses during autumn and winter. For the greenhouse gas balance of a cropping system the effect of reduced tillage and cover crops on N2O...

  18. [Effects of different straw recycling and tillage methods on soil respiration and microbial activity].

    Science.gov (United States)

    Li, Xiao-sha; Wu, Ning; Liu, Ling; Feng, Yu-peng; Xu, Xu; Han, Hui-fang; Ning, Tang-yuan; Li, Zeng-jia

    2015-06-01

    To explore the effects of different tillage methods and straw recycling on soil respiration and microbial activity in summer maize field during the winter wheat and summer maize double cropping system, substrate induced respiration method and CO2 release method were used to determine soil microbial biomass carbon, microbial activity, soil respiration, and microbial respiratory quotient. The experiment included 3 tillage methods during the winter wheat growing season, i.e., no-tillage, subsoiling and conventional tillage. Each tillage method was companied with 2 straw management patterns, i.e., straw recycling and no straw. The results indicated that the conservation tillage methods and straw recycling mainly affected 0-10 cm soil layer. Straw recycling could significantly improve the microbial biomass carbon and microbial activity, while decrease microbial respiratory quotient. Straw recycling could improve the soil respiration at both seedling stage and anthesis, however, it could reduce the soil respiration at filling stage, wax ripeness, and harvest stage. Under the same straw application, compared with conventional tillage, the soil respiration and microbial respiratory quotient in both subsoiling and no-tillage were reduced, while the microbial biomass carbon and microbial activity were increased. During the summer maize growing season, soil microbial biomass carbon and microbial activity were increased in straw returning with conservation tillage, while the respiratory quotient was reduced. In 0-10 cm soil layer, compared with conventional tillage, straw recycling with subsoiling and no-tillage significantly increased soil microbial biomass carbon by 95.8% and 74.3%, and increased soil microbial activity by 97.1% and 74.2%, respectively.

  19. [Effects of no-tillage and stubble-remaining on soil enzyme activities in broadcasting rice seedlings paddy field].

    Science.gov (United States)

    Ren, Wan-Jun; Huang, Yun; Wu, Jin-Xiu; Liu, Dai-Yin; Yang, Wen-Yu

    2011-11-01

    A field experiment was conducted to study the effects of four cultivation modes (conventional tillage, no-tillage, conventional tillage + stubble-remaining, and no-tillage + stubble-remaining) on the activities of urease, acid phosphatase, protease, and cellulose in different soil layers in a broadcasting rice seedlings paddy field. Under the four cultivation modes, the activities of test enzymes were higher in upper than in deeper soil layers, and had a greater difference between the soil layers under no-tillage + stubble-remaining. In upper soil layers, the activities of test enzymes were higher in the treatments of no-tillage than in the treatments of conventional tillage, being the highest under no-tillage + stubble-remaining and the lowest under conventional tillage. In deeper soil layers, the test enzyme activities were the highest under conventional tillage + stubble-remaining, followed by no-tillage + stubble-remaining, no-tillage, and conventional tillage. During the growth period of rice, soil urease and cellulose activities were lower at tillering stage, increased to the maximum at booting stage, and decreased then, soil acid phosphatase activity was higher at tillering stage but lower at elongating stage, whereas soil protease activity peaked at tillering and heading stages.

  20. Effects of over-winter green cover on soil solution nitrate concentrations beneath tillage land.

    Science.gov (United States)

    Premrov, Alina; Coxon, Catherine E; Hackett, Richard; Kirwan, Laura; Richards, Karl G

    2014-02-01

    There is a growing need to reduce nitrogen losses from agricultural systems to increase food production while reducing negative environmental impacts. The efficacy of vegetation cover for reducing nitrate leaching in tillage systems during fallow periods has been widely investigated. Nitrate leaching reductions by natural regeneration (i.e. growth of weeds and crop volunteers) have been investigated to a lesser extent than reductions by planted cover crops. This study compares the efficacy of natural regeneration and a sown cover crop (mustard) relative to no vegetative cover under both a reduced tillage system and conventional plough-based system as potential mitigation measures for reducing over-winter soil solution nitrate concentrations. The study was conducted over three winter fallow seasons on well drained soil, highly susceptible to leaching, under temperate maritime climatic conditions. Mustard cover crop under both reduced tillage and conventional ploughing was observed to be an effective measure for significantly reducing nitrate concentrations. Natural regeneration under reduced tillage was found to significantly reduce the soil solution nitrate concentrations. This was not the case for the natural regeneration under conventional ploughing. The improved efficacy of natural regeneration under reduced tillage could be a consequence of potential stimulation of seedling germination by the autumn reduced tillage practices and improved over-winter plant growth. There was no significant effect of tillage practices on nitrate concentrations. This study shows that over winter covers of mustard and natural regeneration, under reduced tillage, are effective measures for reducing nitrate concentrations in free draining temperate soils.

  1. Direct effects of tillage on the activity density of ground beetle (Coleoptera: Carabidae) weed seed predators.

    Science.gov (United States)

    Shearin, A F; Reberg-Horton, S C; Gallandt, E R

    2007-10-01

    Ground beetles are well known as beneficial organisms in agroecosystems, contributing to the predation of a wide range of animal pests and weed seeds. Tillage has generally been shown to have a negative effect on ground beetles, but it is not known whether this is because of direct mortality or the result of indirect losses resulting from dispersal caused by habitat deterioration. In 2005, field experiments measured direct, tillage-induced mortality, of four carabid weed seed predators, Harpalus rufipes DeGeer, Agonum muelleri Herbst, Anisodactylus merula Germar, and Amara cupreolata Putzeys, and one arthropod predator, Pterostichus melanarius Illiger, common to agroecosystems in the northeastern United States. Three tillage treatments (moldboard plow, chisel plow, and rotary tillage) were compared with undisturbed controls at two sites (Stillwater and Presque Isle) and at two dates (July and August) in Maine. Carabid activity density after disturbance was measured using fenced pitfall traps installed immediately after tillage to remove any effects of dispersal. Rotary tillage and moldboard plowing reduced weed seed predator activity density 52 and 54%, respectively. Carabid activity density after chisel plowing was similar to the undisturbed control. This trend was true for each of the weed seed predator species studied. However, activity density of the arthropod predator P. melanarius was reduced by all tillage types, indicating a greater sensitivity to tillage than the four weed seed predator species. These results confirm the need to consider both direct and indirect effects of management in studies of invertebrate seed predators.

  2. The effect of conservation tillage forward speed and depth on farm fuel consumption

    Directory of Open Access Journals (Sweden)

    A Jalali

    2015-09-01

    Full Text Available Introduction: In recent years, production techniques and equipment have been developed for conservation tillage systems that have been adopted by many farmers. With proper management, overall yield averages for conventional and reduced tillage systems are nearly identical. Sometimes, field operations can be combined by connecting two or more implements. Much research has focused on either reducing or eliminating tillage operations to develop sustainable crop production methods. The greatest costs in farm operations are associated with tillage due to greater specific energy requirement in tillage and the high fuel costs. Combined operations reduce both fuel consumption and time and labor requirements by eliminating at least one individual trip over the field. Light tillage, spraying, or fertilizing operations can be combined with eitherprimary or secondary tillage or planting operations. The amount of fuel saved depends on the combined operations. Generally, light tillage, spraying, and fertilizing operations consume between 0.25 and 0.50 gallons of diesel fuel per acre. Fuel savings of 0.12 to 0.33 gallons per acre can usually be expected from combining operations. Eliminating one primary tillage operation and combining one light tillage, spraying, or fertilizing operation with another tillage or planting operation can usually save at least a gallon of diesel fuel per acre. Combining operations has the added benefit of reducing wheel traffic and compaction. To improve the tillage energy efficiency, implementing effective and agronomic strategies should be improved. Different tillage systems should be tested to determine the most energy efficient ones. Tillage helps seed growth and germination through providing appropriate conditions for soil to absorb sufficient temperature and humidity. Tillage is a time consuming and expensive procedure. With the application of agricultural operations, we can save considerable amounts of fuel, time and

  3. [Priming Effects of Soil Moisture on Soil Respiration Under Different Tillage Practices].

    Science.gov (United States)

    Zhang, Yan; Liang, Ai-zhen; Zhang, Xiao-ping; Chen, Sheng-long; Sun, Bing-jie; Liu, Si-yi

    2016-03-15

    In the early stage of an incubation experiment, soil respiration has a sensitive response to different levels of soil moisture. To investigate the effects of soil moisture on soil respiration under different tillage practices, we designed an incubation trial using air-dried soil samples collected from tillage experiment station established on black soils in 2001. The tillage experiment consisted of no-tillage (NT), ridge tillage (RT), and conventional tillage (CT). According to field capacity (water-holding capacity, WHC), we set nine moisture levels including 30%, 60%, 90%, 120%, 150%, 180%, 210%, 240%, 270% WHC. During the 22-day short-term incubation, soil CO₂ emission was measured. In the early stage of incubation, the priming effects occurred under all tillage practices. There were positive correlations between soil respiration and soil moisture. In addition to drought and flood conditions, soil CO₂ fluxes followed the order of NT > RT > CT. We fitted the relationship between soil moisture and soil CO₂ fluxes under different tillage practices. In the range of 30%-270% WHC, soil CO₂ fluxes and soil moisture fitted a quadratic regression equation under NT, and linear regression equations under RT and CT. Under the conditions of 30%-210% WHC of both NT and RT, soil CO₂ fluxes and soil moisture were well fitted by the logarithmic equation with fitting coefficient R² = 0.966 and 0.956, respectively.

  4. The effect of conservation tillage on crop yield in China

    Directory of Open Access Journals (Sweden)

    Hongwen LI,Jin HE,Huanwen GAO,Ying CHEN,Zhiqiang ZHANG

    2015-06-01

    Full Text Available Traditional agricultural practices have resulted in decreased soil fertility, shortage of water resources and deterioration of agricultural ecological environment, which are seriously affecting grain production. Conservation tillage (CT research has been developed and applied in China since the 1960s and 1970s, and a series of development policies have been issued by the Chinese government. Recent research and application have shown that CT has positive effects on crop yields in China. According to the data from the Conservation Tillage Research Center (CTRC, Chinese Ministry of Agriculture (MOA, the mean crop yield increase can be at least 4% in double cropping systems in the North China Plain and 6% in single cropping systems in the dryland areas of North-east and North-west China. Crop yield increase was particularly significant in dryland areas and drought years. The mechanism for the yield increase in CT system can be attributed to enhanced soil water content and improved soil properties. Development strategies have been implemented to accelerate the adoption of CT in China.

  5. Tillage and residue effects on rainfed wheat and corn production in the Semi-Arid Regions of Northern China

    NARCIS (Netherlands)

    Wang, X.B.; Hoogmoed, W.B.; Perdok, U.D.; Cai, D.X.

    2003-01-01

    Field studies on tillage and residue management for spring corn were conducted at two sites, in Tunliu (1987-1990), and Shouyang (1992-1995) counties of Shanxi province in the semihumid arid regions of northern China. This paper discusses the effects of different fall tillage (winter fallow tillage)

  6. Effects of ridge tillage on photosynthesis and root characters of rice

    Directory of Open Access Journals (Sweden)

    Yao Yuan-zhi

    2015-03-01

    Full Text Available Rice (Oryza sativa L. is an important crop and breeding has not been able to improve yield. Root characteristics of hybrid rice 'Zhuliangyou 02' under conventional tillage and ridge tillage were studied in a Calcisols in Huaihua, China, from 2011 to 2013 to find better tillage methods to resolve massive water consumption, improve yield, and enhance productivity of agricultural labor for rice cultivation. Results showed ridge tillage increased photosynthetic parameters such as photosynthetic rate (P N, stomatal conductance (g s, and water use efficiency (WUE. It also significantly enhanced rice root number, root activity, and antioxidant enzyme activities; it also increased effective panicle number and actual yield by 22.12% and 15.18%, respectively, and enhanced aerenchymae during the early growth stage. Overall, ridge tillage could promote hybrid rice yields by enhancing root absorption, gas exchange, and reducing water consumption. It could be widely used in rice cultivation.

  7. The effect of tillage intensity on soil structure and winter wheat root/shoot growth

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Hansen, Elly Møller; Olesen, Jørgen E

    2008-01-01

    of this study was to investigate the effect of tillage intensity on crop growth dynamics and soil structure. A tillage experiment was established in autumn 2002 on two Danish sandy loams (Foulum and Flakkebjerg) in a cereal-based crop rotation. The tillage systems included in this study were direct drilling (D...... with decreasing tillage intensity for the first year winter wheat at Foulum. In general ploughing resulted in the highest grain yields. This study highlights the important interaction between soil structure and crop growth dynamics....... was followed during the growing seasons using spectral reflectance and mini-rhizotron measurements, respectively. A range of soil physical properties were measured. We found decreased early season shoot and root growth with decreasing tillage intensity. Differences diminished later in the growing season...

  8. Tillage Effect on Organic Carbon in a Purple Paddy Soil

    Institute of Scientific and Technical Information of China (English)

    HUANG Xue-Xia; GAO Ming; WEI Chao-Fu; XIE De-Ti; PAN Gen-Xing

    2006-01-01

    The distribution and storage of soil organic carbon (SOC) based on a long-term experiment with various tillage systems were studied in a paddy soil derived from purple soil in Chongqing, China. Organic carbon storage in the 0-20and 0-40 cm soil layers under different tillage systems were in an order: ridge tillage with rice-rape rotation (RT-rr)> conventional tillage with rice only (CT-r) > ridge tillage with rice only (RT-r) > conventional tillage with rice-rape rotation (CT-rr). The RT-rr system had significantly higher levels of soil organic carbon in the 0-40 cm topsoil, while the proportion of the total remaining organic carbon in the total soil organic carbon in the 0-10 cm layer was greatest in the RT-rr system. This was the reason why the RT-rr system enhanced soil organic carbon storage. These showed that tillage system type was crucial for carbon storage. Carbon levels in soil humus and crop-yield results showed that the RT-rr system enhanced soil fertility and crop productivity. Adoption of this tillage system would be beneficial both for environmental protection and economic development.

  9. Effect of tillage on macropore flow and phosphorus transport to tile drains

    Science.gov (United States)

    Williams, Mark R.; King, Kevin W.; Ford, William; Buda, Anthony R.; Kennedy, Casey D.

    2016-04-01

    Elevated phosphorus (P) concentrations in subsurface drainage water are thought to be the result of P bypassing the soil matrix via macropore flow. The objectives of this study were to quantify event water delivery to tile drains via macropore flow paths during storm events and to determine the effect of tillage practices on event water and P delivery to tiles. Tile discharge, total dissolved P (DP) and total P (TP) concentrations, and stable oxygen and deuterium isotopic signatures were measured from two adjacent tile-drained fields in Ohio, USA during seven spring storms. Fertilizer was surface-applied to both fields and disk tillage was used to incorporate the fertilizer on one field while the other remained in no-till. Median DP concentration in tile discharge prior to fertilizer application was 0.08 mg L-1 in both fields. Following fertilizer application, median DP concentration was significantly greater in the no-tilled field (1.19 mg L-1) compared to the tilled field (0.66 mg L-1), with concentrations remaining significantly greater in the no-till field for the remainder of the monitored storms. Both DP and TP concentrations in the no-till field were significantly related to event water contributions to tile discharge, while only TP concentration was significantly related to event water in the tilled field. Event water accounted for between 26 and 69% of total tile discharge from both fields, but tillage substantially reduced maximum contributions of event water. Collectively, these results suggest that incorporating surface-applied fertilizers has the potential to substantially reduce the risk of P transport from tile-drained fields.

  10. Tillage and nutrient source effects on water quality and corn grain yield from a flat landscape.

    Science.gov (United States)

    Thoma, David P; Gupta, Satish C; Strock, Jeffrey S; Moncrief, John F

    2005-01-01

    Beneficial effects of leaving residue at the soil surface are well documented for steep lands, but not for flat lands that are drained with surface inlets and tile lines. This study quantified the effects of tillage and nutrient source on tile line and surface inlet water quality under continuous corn (Zea mays L.) from relatively flat lands (<3%). Tillage treatments were either fall chisel or moldboard plow. Nutrient sources were either fall injected liquid hog manure or spring incorporated urea. The experiment was on a Webster-Canisteo clay loam (Typic Endoaquolls) at Lamberton, MN. Surface inlet runoff was analyzed for flow, total solids, NO(3)-N, NH(4)-N, dissolved P, and total P. Tile line effluent was analyzed for flow, NO(3)-N, and NH(4)-N. In four years of rainstorm and snowmelt events there were few significant differences (p < 0.10) in water quality of surface inlet or tile drainage between treatments. Residue cover minimally reduced soil erosion during both snowmelt and rainfall runoff events. There was a slight reduction in mineral N losses via surface inlets from manure treatments. There was also a slight decrease (p = 0.025) in corn grain yield from chisel-plow plots (9.7 Mg ha(-1)) compared with moldboard-plow plots (10.1 Mg ha(-1)). Chisel plowing (approximately 30% residue cover) alone is not sufficient to reduce nonpoint source sediment pollution from these poorly drained flat lands to the extent (40% reduction) desired by regulatory agencies.

  11. No-tillage effects on N and P exports across a rice-planted watershed.

    Science.gov (United States)

    Liang, Xinqiang; Wang, Zhibo; Zhang, Yixiang; Zhu, Chunyan; Lin, Limin; Xu, Lixian

    2016-05-01

    No tillage (NT) can be used as a management tool to alleviate the negative effects of agricultural practices on the environment by reducing the runoff volume and nutrient exports. The main objective of this research was to quantify the effect of NT on nitrogen (N) and phosphorus (P) exports across a rice-planted watershed using the soil and water assessment tool (SWAT) model. Results show that total N and P runoff exports from rice fields across the watershed ranged from 7.2 to 22.8 kg N/ha and 0.56 to 6.80 kg P/ha, respectively, over five rice-growing seasons under conventional tillage (CT) practice. The adoption of NT reduced the runoff volume, and the total N and total P exports by 25.9, 8.5, and 7.8 %, respectively, compared with the total exports under CT practice in the same study area. Rice yields were reduced by 0.7-1.9 % within the first 4 years after the adoption of NT, but began to rise in the fifth year. These results suggest that a long-term period of NT practice is necessary to reduce N and P exports without comprising the rice yield on rice-planted watersheds. In addition, the benefits of implementing NT practice alone were limited, and other practices, such as water and nutrient management, should be combined with NT practice.

  12. Effect of simulated tillage on microbial autotrophic CO2 fixation in paddy and upland soils.

    Science.gov (United States)

    Ge, Tida; Wu, Xiaohong; Liu, Qiong; Zhu, Zhenke; Yuan, Hongzhao; Wang, Wei; Whiteley, A S; Wu, Jinshui

    2016-01-22

    Tillage is a common agricultural practice affecting soil structure and biogeochemistry. To evaluate how tillage affects soil microbial CO2 fixation, we incubated and continuously labelled samples from two paddy soils and two upland soils subjected to simulated conventional tillage (CT) and no-tillage (NT) treatments. Results showed that CO2 fixation ((14)C-SOC) in CT soils was significantly higher than in NT soils. We also observed a significant, soil type- and depth-dependent effect of tillage on the incorporation rates of labelled C to the labile carbon pool. Concentrations of labelled C in the carbon pool significantly decreased with soil depth, irrespective of tillage. Additionally, quantitative PCR assays revealed that for most soils, total bacteria and cbbL-carrying bacteria were less abundant in CT versus NT treatments, and tended to decrease in abundance with increasing depth. However, specific CO2 fixation activity was significantly higher in CT than in NT soils, suggesting that the abundance of cbbL-containing bacteria may not always reflect their functional activity. This study highlights the positive effect of tillage on soil microbial CO2 fixation, and the results can be readily applied to the development of sustainable agricultural management.

  13. Effect of Tillage Systems with Corn Residue on Grain Yield of Rapeseed in Moghan Region

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    J Taghinazhad

    2014-09-01

    Full Text Available This study carried out to evaluate the effect of different tillage systems on rapeseed yield (hayola 401 planted in corn residues. This experiment was done in Moghan region with clay soils during 2009-2012. Different seedbed preparation methods include MT: moldboard + disk tillage (conventional tillage was included, SCT: Stem Crusher + chisel + disk tandem harrow, STT: Stem Crusher + double-disc, CT: chisel + disk tillage and DD: two heavy disks. The experiment was conducted in a randomized complete block design with four replications. The results showed that soil bulk density in the 0-10 cm layer was not significant in different tillage treatments, but it was significantly higher than the conventional tillage in 10-20 cm depth. However, penetration resistance in 10-30 cm under DD was significantly higher than other treatments, but it was not significant in 0-10 cm layer among all tillage treatments. Thus, Comparison of the soil bulk density, penetration resistance, and plant establishment showed that the reduced tillage in canola seedbed preparation was effective. Besides, the surveys indicated that there was a significant different between MWD after primary and secondary tillage. The mean diameter weighted under SCT and DD, were 1.19 and 1.24 cm, respectively had the best status. The highest value and the worst status of this parameter observed for MT which was 1.92 cm. The highest rate of grain yield obtained by application of treatment SCT, and it was 2563.8 kg ha-1, The SCT treatment can be recommended as an effective canola bed preparation due to its significant saving in time and cost after corn harvesting.

  14. [Effects of tillage mode on black soil's penetration resistance and bulk density].

    Science.gov (United States)

    Chen, Xue-Wen; Zhang, Xiao-Ping; Liang, Ai-Zhen; Jia, Shu-Xia; Shi, Xiu-Huan; Fan, Ru-Qin; Wei, Shou-Cai

    2012-02-01

    Taking an eight-year field experiment site in Dehui County of Jilin Province, Northeast China as test object, this paper studied the effects of different tillage modes (no tillage and ploughing in autumn) on the penetration resistance and bulk density of black soil. No tillage increased the soil penetration resistance, especially at the soil depth of 2.5-17.5 cm. In the continuous cropping of maize and the rotation of maize-soybean, the maximum soil penetration resistance at planting zone under no tillage and ploughing in autumn was 2816 and 1931 kPa, and 2660 and 2051 kPa, respectively, which had no restriction on the crop growth. The curve of soil penetration resistance under ploughing in autumn changed with ridge shape, while that under no tillage changed less. Comparing with ploughing in autumn, no tillage increased the bulk density of 5-20 cm soil layer significantly. Under no tillage, the bulk density of 5-30 cm soil layer changed little, but under ploughing in autumn, soil bulk density increased gradually with increasing soil depth. There was no significant correlation between soil bulk density and soil penetration resistance.

  15. [Effects of different tillage methods on phospholipid fatty acids and enzyme activities in calcareous cinnamon soil].

    Science.gov (United States)

    Pei, Xue-Xia; Dang, Jian-You; Zhang, Ding-Yi; Wang, Jiao-Ai; Zhang, Jing

    2014-08-01

    In order to study changes of physical and chemical characteristics and microbial activities in soil under different tillage methods, effects of four tillage methods, rotary tillage (RT), subsoil tillage (ST), conventional tillage (CT) with corn straw returned to soil, and rotary tillage with no corn straw returned to soil (CK), on phospholipid fatty acids (PLFA) characteristics and hydrolase enzymes activities in calcareous cinnamon soil were investigated. The results showed that soil hydrolase enzymes activities, nutrient contents, microbial diversity varied greatly with the different tillage methods. Returning corn straw to soil increased the kinds, amount of soil total PLFAs, bacteria PLFAs and actonomycetes PLFAs, while decreased the fungi PLFAs, indicating that fungi was more adaptable than bacteria to an infertile environment. ST and CT resulted in higher amounts of total PLFAs, which were 74.7% and 53.3% higher than that of CK, indicating they were more beneficial to the growth of plants. They could also improve soil physical and chemical properties, increase alk-phosphatase, protease and urease activities, which would provide a favorable soil condition for high and stable crop yields.

  16. Effect of Tillage and Staking on the production of fluted Pumpkin

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    C.G Okeke

    2016-06-01

    Full Text Available A field experiment was conducted using fluted pumpkin (telfairia occidentals to determine the effect of 3 different tillage (zero, mound and flat and 3 different staking (zero, individual and pyramid on a sandy clay loam soil of the humid tropics at faculty research farm Esut, Enugu Southeastern Nigeria between June and December, 2008. The treatment consists of 3 levels of tillage and3 levels of staking as mentioned above. The experiment was a 3 x 3 factorial laid out in randomized complete block design (RCBD with four replications and nine treatments. The results obtained revealed significant different of p 0.05 among some of the ç. treatments. The highest number of vine length and number of flower per plant of 196.16 and 36 were obtained from zero tillage / individual staking while the least were recorded for flat tillage/individual staking of 115.19 and zero tillage/pyramidal staking of 3 respectively. Average leaf yield ranged from 277.7 to 852.5 (g were obtained. Based on their performance, treatment 5 (mound tillage/individual staking and treatment, 6(mound tillage/pyramidal staking have the highest leaf yield.

  17. THE EFFECT OF INTERCROPS AND DIFFERENTIATED TILLAGE ON THE MAIZE YIELDING

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    Andrzej Biskupski

    2014-10-01

    Full Text Available The research was carried out in the years 2008–2010 in the fields of the Experimental Station IUNG at Jelcz-Laskowice. Two-factorial experiments were laid out on the grey-brown podzolic soil formed out of loamy sand silt by the method of randomized subblocks in four replications. The experimental factors were intercrops (mustard and lupine and tillage system (traditional, simplified and zero. Winter wheat was the forecrop and maize the sequent plant. Leaf area index (LAI and mean tip angle (MTA were determined in the stage of early flowering with use of a LAI-2000 meter (LI-COR, USA in four replications. The research was carried out to find out which tillage system and intercrop would positively influence the yielding, selected indices of canopy architecture (height of plants, LAI, MTA and the amount of weeds in maize grown for grain. The yield of maize grain grown in simplified and zero tillage appeared to be lower than that obtained in traditional tillage. The highest LAI index of maize grown after both forecrops was found with traditional tillage, while the lowest with zero one. The highest maize plants were those in conventional tillage. The intercrop which appeared to have the most favourable effect on the height of maize was mustard. Reduced tillage systems increased total weed infestation in comparison to conventional tillage. Compensation of Echinochloa crus-galli, Geranium pusillum and Chenopodium album was noticed. The greatest number of weeds per unit area was found in the experiment after no-tillage system.

  18. Defining the effect of sweep tillage tool cutting edge geometry on tillage forces using 3D discrete element modelling

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    Mustafa Ucgul

    2015-09-01

    Full Text Available The energy required for tillage processes accounts for a significant proportion of total energy used in crop production. In many tillage processes decreasing the draft and upward vertical forces is often desired for reduced fuel use and improved penetration, respectively. Recent studies have proved that the discrete element modelling (DEM can effectively be used to model the soil–tool interaction. In his study, Fielke (1994 [1] examined the effect of the various tool cutting edge geometries, namely; cutting edge height, length of underside rub, angle of underside clearance, on draft and vertical forces. In this paper the experimental parameters of Fielke (1994 [1] were simulated using 3D discrete element modelling techniques. In the simulations a hysteretic spring contact model integrated with a linear cohesion model that considers the plastic deformation behaviour of the soil hence provides better vertical force prediction was employed. DEM parameters were determined by comparing the experimental and simulation results of angle of repose and penetration tests. The results of the study showed that the simulation results of the soil-various tool cutting edge geometries agreed well with the experimental results of Fielke (1994 [1]. The modelling was then used to simulate a further range of cutting edge geometries to better define the effect of sweep tool cutting edge geometry parameters on tillage forces. The extra simulations were able to show that by using a sharper cutting edge with zero vertical cutting edge height the draft and upward vertical force were further reduced indicating there is benefit from having a really sharp cutting edge. The extra simulations also confirmed that the interpolated trends for angle of underside clearance as suggested by Fielke (1994 [1] where correct with a linear reduction in draft and upward vertical force for angle of underside clearance between the ranges of −25 and −5°, and between −5 and 0°. The

  19. The effects of forward speed and depth of conservation tillage on soil bulk density

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    A Mahmoudi

    2015-09-01

    , besides the importance of tillage depth and speed in different tiller performance. Materials and methods: This investigation was carried out based on random blocks in the form of split plot experimental design. The main factor, tillage depth, (was 10 and 20cm at both levels and the second factor, tillage speed, (was 6, 8, 10, 12 km h-1 in four levels for Bostan-Abad and 8,10,12,14 km h-1 for Hashtrood with four repetitions. It was carried out using complex tillage made in Sazeh Keshte Bukan Company, which is mostly used in Eastern Azerbaijanand using Massey Ferguson 285 and 399 tractors in Bostab-Abad and Hashtrood, respectively. In this investigation, the characteristics of soil bulk density were studied in two sampling depths of 7 and 17 centimeters. Bulk density is an indicator of soil compaction. It is calculated as the dry weight of soil divided by its volume. This volume includes the volume of soil particles and the volume of pores among soil particles. Bulk density is typically expressed in g cm-3. Results and Discussion: In this study, the effect of both factors on the feature of the soil bulk density at the sampling depth of 5-10 and 15-20 cm was examined. In Bostan-Abad, regarding tillage speed effect for studies characteristics at 1% probability level on soil bulk density was effective. The effect of tillage depth on the soil bulk density was significant at 5% probability level . The interaction effect of tillage speed and depth on soil bulk density was significant at probability level of 1%. Regarding sampling depth effect, the soil bulk density was significant at 5% probability level, respectively. In Hashtrood, the effect of tillage speed on soil bulk density at probability level of 1%, and also tillage depth effect on soil bulk density was significant at 5% level of probability. The interaction effect of tillage speed and depth on soil bulk density was significant at 5% level of probability. Regarding the depth of sampling it was significant on soil bulk

  20. Effects of tillage and nitrogen fertilizers on CH4 and CO2 emissions and soil organic carbon in paddy fields of central China.

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    Li Cheng-Fang

    Full Text Available Quantifying carbon (C sequestration in paddy soils is necessary to help better understand the effect of agricultural practices on the C cycle. The objective of the present study was to assess the effects of tillage practices [conventional tillage (CT and no-tillage (NT] and the application of nitrogen (N fertilizer (0 and 210 kg N ha(-1 on fluxes of CH(4 and CO(2, and soil organic C (SOC sequestration during the 2009 and 2010 rice growing seasons in central China. Application of N fertilizer significantly increased CH(4 emissions by 13%-66% and SOC by 21%-94% irrespective of soil sampling depths, but had no effect on CO(2 emissions in either year. Tillage significantly affected CH(4 and CO(2 emissions, where NT significantly decreased CH(4 emissions by 10%-36% but increased CO(2 emissions by 22%-40% in both years. The effects of tillage on the SOC varied with the depth of soil sampling. NT significantly increased the SOC by 7%-48% in the 0-5 cm layer compared with CT. However, there was no significant difference in the SOC between NT and CT across the entire 0-20 cm layer. Hence, our results suggest that the potential of SOC sequestration in NT paddy fields may be overestimated in central China if only surface soil samples are considered.

  1. Residual effect of soil tillage on water erosion from a Typic Paleudalf under long-term no-tillage and cropping systems

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    Mastrângello Enívar Lanzanova

    2013-12-01

    Full Text Available Soil erosion is one of the chief causes of agricultural land degradation. Practices of conservation agriculture, such as no-tillage and cover crops, are the key strategies of soil erosion control. In a long-term experiment on a Typic Paleudalf, we evaluated the temporal changes of soil loss and water runoff rates promoted by the transition from conventional to no-tillage systems in the treatments: bare soil (BS; grassland (GL; winter fallow (WF; intercrop maize and velvet bean (M+VB; intercrop maize and jack bean (M+JB; forage radish as winter cover crop (FR; and winter cover crop consortium ryegrass - common vetch (RG+CV. Intensive soil tillage induced higher soil losses and water runoff rates; these effects persisted for up to three years after the adoption of no-tillage. The planting of cover crops resulted in a faster decrease of soil and water loss rates in the first years after conversion from conventional to no-tillage than to winter fallow. The association of no-tillage with cover crops promoted progressive soil stabilization; after three years, soil losses were similar and water runoff was lower than from grassland soil. In the treatments of cropping systems with cover crops, soil losses were reduced by 99.7 and 66.7 %, compared to bare soil and winter fallow, while the water losses were reduced by 96.8 and 71.8 % in relation to the same treatments, respectively.

  2. Effects of Subsoiling on Soil Moisture Under No-Tillage for Two Years

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to improve the water use efficiency under conservation tillage, the effects of subsoiling on soil moisture under no tillage were studied. An experiment of 40 cm subsoiling in a field kept under no-tillage for 2 years was operated from 2005 to 2006. Based on the data of the soil moisture and crop yield, the physical basis of subsoiling for water conservation and yield increase was analyzed.The results showed that the soil water storage under subsoiling, from the soil surface to a depth of 100 cm was more than that under no-tillage for the growth season. In the 0-100 cm soil depth,the soil moisture in 50-100 cm depth under subsoiling was more compared with no-tillage, which increased when it's drought and decreased when it's rainy with the increase in soil depth. Compared with no-tillage, subsoiling could reduce the water consumption of oats in the 0-50 cm depth and increase the water consumption in the 50-100 cm depth. Also, subsoiling increased the yield by 18.29% and the water use efficiency by 16.8% in a two-year average. The effects of subsoiling on water conservation and yield increase were affected by precipitation, and a well-proportioned rainfall was better to increase yield and water use efficiency. Meanwhile, subsoiling decreased bulk density, which increased with the available precipitation. Subsoiling under no-tillage is the effective rotation tillage to contain more soil moisture and improve water use efficiency in ecotone of North China.

  3. Effect of tillage and water management on GHG emissions from Mediterranean rice growing ecosystems

    Science.gov (United States)

    Fangueiro, David; Becerra, Daniel; Albarrán, Ángel; Peña, David; Sanchez-Llerena, Javier; Rato-Nunes, José Manuel; López-Piñeiro, Antonio

    2017-02-01

    Paddy rice fields are an important source of greenhouse gases (GHG), especially methane. In the present work, we assessed the impact on GHG emissions of two main parameters of rice production: aerobic rice production was compared with traditional flooded rice production and conventional tillage (CT) was compared with short-term and long-term no-tillage (NT) management. A field experiment was performed over three years and the GHG emissions were measured during each year. Five treatments (3 replicates) were considered: NTS7: no-tillage over seven years and sprinkler irrigation; NTS: no-tillage and sprinkler irrigation; CTS: conventional tillage and sprinkler irrigation; NTF: no-tillage and flooding; CTF: conventional tillage and flooding. The use of sprinkler irrigation rather than flooding led to decreases in nitrous oxide and methane emissions of ∼40% and more than 99%, respectively, over the 3-year experiment. The use of sprinkler irrigation compared with flooded irrigation reduced the global warming potential (GWP) about 40% and 36% in no-tillage and conventional tillage treatments, respectively. Treatment NTF decreased CH4 emissions, relative to CTF, by ∼60% over three years but the effect of NT on N2O emissions was not clear: a decrease or no effect was mostly observed in the NT treatments, relative to CT. A decrease of ∼40% in the total GHG emissions was observed in the NT treatments, relative to CT. No or small differences between NTS and NTS7 in terms of gaseous emissions were found. The short-term no-tillage and sprinkler irrigated treatment (NTS) gave lower yields than CTF in 2011 and 2012, but reached similar yields in the third year (NTS 8229 kg ha-1;CTF 8926 kg ha-1), with average savings of 75% of the total amount of water applied in CTF. The NTS7 data showed that high yields (reaching 9805 kg ha-1 in 2012) and water savings are sustainable in the long term. Considering the yield-scaled GWP of the emissions, NT gave a decrease of up to 42

  4. Effect of subsoil tillage depth on nutrient accumulation, root distribution, and grain yield in spring maize

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    Hongguang Cai

    2014-10-01

    Full Text Available A four-year field experiment was conducted to investigate the effect of subsoiling depth on root morphology, nitrogen (N, phosphorus (P, and potassium (K uptake, and grain yield of spring maize. The results indicated that subsoil tillage promoted root development, increased nutrient accumulation, and increased yield. Compared with conventional soil management (CK, root length, root surface area, and root dry weight at 0–80 cm soil depth under subsoil tillage to 30 cm (T1 and subsoil tillage to 50 cm (T2 were significantly increased, especially the proportions of roots in deeper soil. Root length, surface area, and dry weight differed significantly among three treatments in the order of T2 > T1 > CK at the 12-leaf and early filling stages. The range of variation of root diameter in different soil layers in T2 treatment was the smallest, suggesting that roots were more likely to grow downwards with deeper subsoil tillage in soil. The accumulation of N, P, and K in subsoil tillage treatment was significantly increased, but the proportions of kernel and straw were different. In a comparison of T1 with T2, the grain accumulated more N and P, while K accumulation in kernel and straw varied in different years. Grain yield and biomass were increased by 12.8% and 14.6% on average in subsoil tillage treatments compared to conventional soil treatment. Although no significant differences between different subsoil tillage depths were observed for nutrient accumulation and grain yield, lodging resistance of plants was significantly improved in subsoil tillage to 50 cm, a characteristic that favors a high and stable yield under extreme environments.

  5. Effects of Tillage Practices on Water Consumption, Water Use Efifciency and Grain Yield in Wheat Field

    Institute of Scientific and Technical Information of China (English)

    ZHENG Cheng-yan; YU Zhen-wen; SHI Yu; CUI Shi-ming; WANG Dong; ZHANG Yong-li; ZHAO Jun-ye

    2014-01-01

    Water shortage is a serious issue threatening the sustainable development of agriculture in the North China Plain, with the winter wheat (Triticum aestivum L.) as its largest water-consuming crop. The effects of tillage practices on the water consumption and water use efifciency (WUE) of wheat under high-yield conditions using supplemental irrigation based on testing soil moisture dynamic change were examined in this study. This experiment was conducted from 2007 to 2010, with ifve tillage practice treatments, namely, strip rotary tillage (SR), strip rotary tillage after subsoiling (SRS), rotary tillage (R), rotary tillage after subsoiling (RS), and plowing tillage (P). The results showed that in the SRS and RS treatments the total water and soil water consumptions were 11.81, 25.18%and 12.16, 14.75%higher than those in SR and R treatments, respectively. The lowest ratio of irrigation consumption to total water consumption in the SRS treatment was 18.53 and 21.88%for the 2008-2009 and 2009-2010 growing seasons, respectively. However, the highest percentage of water consumption was found in the SRS treatment from anthesis to maturity. No signiifcant difference was found between the WUE of the lfag leaf at the later iflling stage in the SRS and RS treatments, but the lfag leaf WUE at these stages were higher than those of other treatments. The SRS and RS treatments exhibited the highest grain yield (9 573.76 and 9 507.49 kg ha-1 for 3-yr average) with no signiifcant difference between the two treatments, followed by P, R and SR treatments. But the SRS treatment had the highest WUE. Thus, the 1-yr subsoiling tillage, plus 2 yr of strip rotary planting operation may be an efifcient measure to increase wheat yield and WUE.

  6. Effect of subsoil tillage depth on nutrient accumulation, root distribution, and grain yield in spring maize

    Institute of Scientific and Technical Information of China (English)

    Hongguang; Cai; Wei; Ma; Xiuzhi; Zhang; Jieqing; Ping; Xiaogong; Yan; Jianzhao; Liu; Jingchao; Yuan; Lichun; Wang; Jun; Ren

    2014-01-01

    A four-year field experiment was conducted to investigate the effect of subsoiling depth on root morphology, nitrogen(N), phosphorus(P), and potassium(K) uptake, and grain yield of spring maize. The results indicated that subsoil tillage promoted root development,increased nutrient accumulation, and increased yield. Compared with conventional soil management(CK), root length, root surface area, and root dry weight at 0–80 cm soil depth under subsoil tillage to 30 cm(T1) and subsoil tillage to 50 cm(T2) were significantly increased, especially the proportions of roots in deeper soil. Root length, surface area, and dry weight differed significantly among three treatments in the order of T2 > T1 > CK at the12-leaf and early filling stages. The range of variation of root diameter in different soil layers in T2 treatment was the smallest, suggesting that roots were more likely to grow downwards with deeper subsoil tillage in soil. The accumulation of N, P, and K in subsoil tillage treatment was significantly increased, but the proportions of kernel and straw were different. In a comparison of T1 with T2, the grain accumulated more N and P, while K accumulation in kernel and straw varied in different years. Grain yield and biomass were increased by 12.8% and 14.6% on average in subsoil tillage treatments compared to conventional soil treatment. Although no significant differences between different subsoil tillage depths were observed for nutrient accumulation and grain yield, lodging resistance of plants was significantly improved in subsoil tillage to 50 cm, a characteristic that favors a high and stable yield under extreme environments.

  7. [Effects of tillage and straw returning on microorganism quantity, enzyme activities in soils and grain yield].

    Science.gov (United States)

    Zhao, Ya-li; Guo, Hai-bin; Xue, Zhi-wei; Mu, Xin-yuan; Li, Chao-hai

    2015-06-01

    A two-year field study with split plot design was conducted to investigate the effects of different soil tillage (conventional tillage, CT; deep tillage, DT; subsoil tillage, ST) and straw returning (all straw retention, AS; no straw returning, NS) on microorganism quantity, enzyme activities in soil and grain yield. The results showed that, deep or subsoil tillage and straw returning not only reduced the soil bulk density and promoted the content of organic carbon in soil, but increased the soil microbial quantity, soil enzyme activities and grain yield. Furthermore, such influences in maize season were greater than that in wheat season. Compared with CT+NS, DT+AS and ST+AS decreased the soil bulk density at 20-30 cm depth by 8.5% and 6.6%, increased the content of soil organic carbon by 14.8% and 12.4%, increased the microorganism quantity by 45.9% and 33.9%, increased the soil enzyme activities by 34.1% and 25.5%, increased the grain yield by 18.0% and 19.3%, respectively. No significant difference was observed between DT+AS and ST+AS. We concluded that retaining crop residue and deep or subsoil tillage improved soil microorganism quantity, enzyme activities and crop yield.

  8. The tillage effect on the soil acid and alkaline phosphatase activity

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    Lacramioara Oprica

    2011-12-01

    Full Text Available Phosphatases (acid and alkaline are important in soils because these extracellular enzymes catalyze the hydrolysis of organic phosphate esters to orthophosphate; thus they form an important link between biologically unavailable and mineral phosphorous. Phosphatase activity is sensitive to environmental perturbations such as organic amendments, tillage, waterlogging, compaction, fertilizer additions and thus it is often used as an environmental indicator of soil quality in riparian ecosystems. The aim of the study was to assess the effect of tillage systems on phosphatases activity in a field experiment carried out in Ezăreni farm. The phosphatase activitiy were determined at two depths (7-10 cm and 15-25cm layers of a chernozem soil submitted to conventional tillage (CT in a fertilised and unfertilised experiment. Monitoring soil alkaline phosphatase activity showed, generally, the same in fertilized soil profiles collected from both depths; the values being extremely close. In unfertilized soils, alkaline phosphatase activity is different only in soils that were exposed to unconventional work using disc harrows and 30cm tillage. Both works type (no tillage and conventional tillage cause an intense alkaline phosphatase activity in 7-10 cm soil profile. Acid phosphatase activity is highly fluctuating in both fertilized as well unfertilized soil, this enzyme being influenced by the performed works.

  9. Impact of conservation tillage on nematode populations.

    Science.gov (United States)

    Minton, N A

    1986-04-01

    Literature reporting the development of conservation tillage and the research that has been conducted on nematode control in crops grown in conservation tillage systems is reviewed. Effects of different types of conservation tillage on population densities of various nematode species in monocropping and multicropping systems, effects of tillage on nematode distribution in the soil profile, effects of conservation tillage on nematode control, and the role of nematology in conservation tillage research are discussed.

  10. Effects of Maize Residue Removal and Tillage on Soil Erosion, Carbon, and Macronutrient Dynamics

    Science.gov (United States)

    Beniston, J.; Shipitalo, M.; Lal, R.; Dayton, E. A.; Hopkins, D.; Jones, F. S.; Joynes, A.; Dungait, J.

    2013-12-01

    Erosion by water is a principal process of soil degradation in agricultural lands. Soil erosion influences the storage and fluxes of C and key macronutrients N and P in soil surface layers. No till (NT) crop management significantly reduces erosion on susceptible landscapes. The selective removal of crop residues for bio-energy production from no-till systems has been suggested as a secondary crop, but the effect of this practice on the conservation benefits of NT has not been quantified. Therefore, this study was initiated in spring 2012 to examine the effects of soil management practices on erosion and associated macronutrient fluxes on erodible soils subjected to a high intensity simulated rain storm at the North Appalachian Experimental Watershed (NAEW) in Coshocton, OH, U.S.A. The soil management practices evaluated included: long term no-till with 100% crop residue (NT100) , no-till with 50% crop reside (NT50), NT with complete crop residue removal (NT0), long term conventional tillage (CT), and long term no-tillage plots that were cultivated (TNT) with a rototiller before the rainfall application. A field rainfall simulator was utilized to apply rainfall at an intensity of 7 cm hr-1 to a 4 m2 area of each plot for 30 minutes. Total runoff from the NT0 plots (22.1 mm) was almost double compared with the NT 50% (13.3 mm), CT (12.8 mm) and TNT (12.8 mm) plots and was more than 5 times greater than the NT100 plots (4.4mm). CT and NT0 plots produced 40 (2.7 Mg ha-1) and 20 times (1.4 Mg ha-1) more soil loss, respectively, than NT100 plots (0.07 Mg ha-1). Tillage of the no-till (TNT) soil produced the largest sediment-bound fluxes of C and N, while sediment-bound P fluxes were largest in the CT soils. Natural abundance δ13C and δ15N values were distinct between eroded sediments and the source topsoils and suggested enhanced loss of older (>28 yrs) C residues in CT plots. All observations suggest NT management provides greater resilience to soils than CT during

  11. Effects of tillage on contents of organic carbon, nitrogen, water-stable aggregates and light fraction for four different long-term trials

    Science.gov (United States)

    Andruschkewitsch, R.; Geisseler, D.; Koch, H.-J.; Ludwig, B.

    2012-04-01

    Despite increasing interest in tillage techniques as a factor affecting organic carbon (Corg) dynamics and stabilization mechanisms little is known about the underlying processes. Our objectives were (i) to quantify the impact of different tillage treatments on the amount and distribution of of labile Corg pools, on the water-stable macro-aggregate (>250 µm) contents and on organic carbon (Corg) storage and (ii) to quantify the ability of soils under different tillage treatments, light fraction (LF) inputs and clay contents in macro-aggregate formation. Therefore four long-term tillage trials on loess soil in Germany with regular conventional tillage (CT, to 30 cm), mulch tillage (MT, to 10 cm), and no-tillage (NT) treatments. Samples were taken in 0-5 cm, 5-25 cm and 25-40 cm depth after 18-25 years of different tillage treatments and investigated on free and occluded LF (fLF and oLF, respectively) and on macro-aggregate contents. Furthermore an incubation experiment for the quantifcation of macro-aggregate formation was conducted. Macro-aggregates in soils from CT and NT treatments (0-5 and 5-25 cm soil depth) were destroyed and different amounts of light fraction (LF) and clay were applied. The four long-term tillage trials, differing in texture and climatic conditions, revealed consistent results in Corg storage among each other. Based on the equivalent soil mass approach (CT: 0-40, MT: 0-38, NT: 0-36 cm) the Corg stocks in the sampled profile were significantly higher for the MT treatment than for the CT and NT treatments. Significantly lower Corg, fLF, oLF, and macro-aggregate contents for the soils under CT treatment in comparison with the soils under NT and MT treatments were restricted on the top 5 cm. The correlation of the macro-aggregate content against the fLF and oLF contents suggested that the macro-aggregate content is influenced to a lesser extent directly by the physical impact of the different tillage treatments but by the contents of available

  12. [Effects of tillage mode on water use efficiency and yield of summer maize under different simulated rainfalls].

    Science.gov (United States)

    Chen, Yu; Wen, Xiao-xia; Liao, Yun-cheng

    2013-08-01

    Based on the tillage practices of summer maize and the rainfall pattern in Northwest China, and by using self-made simulated rainfall device, a field experiment was conducted on the effects of plowing, no-tillage, and no-tillage plus mulching on the water use efficiency (WUE) and yield of summer maize under rainfalls 250, 350 and 450 mm from June to September, 2010. Compared with plowing, no-tillage increased the WUE and yield under rainfall 250 mm by 26% and 16.5% and under rainfall 350 mm by 17.6% and 6.1%, respectively. Under rainfall 450 mm, the water storage was smaller in treatment no-tillage than in treatment plowing, and the WUE and yield in treatment no-tillage were 1.1% and 0.6% lower than those in treatment plowing, respectively. No-tillage plus mulching overcame the disadvantage of no-tillage in lesser water-storing under sufficient rainfall than plowing. Under the three rainfalls, no-tillage plus mulching could effectively inhibit the soil evaporation between plants, decrease the invalid water consumption of bare soil, and increase the soil water storage and the rate of evapotranspiration to water consumption. Compared with plowing, no-tillage plus mulching increased the WUE and yield under rainfall 250 mm by 48.6% and 32.9%, under rainfall 350 mm by 51.6% and 27.1%, and under 450 mm rainfall by 23.7% and 13.1%, respectively. In sum, relative to plowing, no-tillage showed its superiority in increasing WUE and yield under rainfalls 250 and 350 mm, whereas no-tillage plus mulching increased the WUE and yield significantly under rainfalls 250 and 450 mm.

  13. Effects of Different Soil Tillage Intensity on Yields of Spring Barley

    Directory of Open Access Journals (Sweden)

    Alena Pernicová

    2014-01-01

    Full Text Available Within the period 1990–2012, effects of different soil tillage intensity on yields of spring barley were studied in a field experiment in the sugar-beet producing region (Ivanovice na Hané, Czech Republic. The forecrop of the spring barley was always sugar beet; following in three different crop rotations, after maize for silage, winter wheat and spring barley. Four variants of tillage were evaluated: Variant 1 – ploughing to the depth of 0.22 m; Variant 2 – shallow ploughing to the depth of 0.15 m; Variant 3 – no tillage; Variant 4 – shallow loosening soil to the depth of 0.10 m.Effect of different tillage on yields of spring barley was statistically insignificant. In all three crop rotations, the highest and the lowest average yields were obtained in Variant 2 (ploughing to the depth of 0.15 m and Variant 1 (ploughing to the depth of 0.22 m, respectively. Average yields in variants of soil tillage were these: variant 1 – 6.42 t.ha−1; variant 2 – 6.57 t.ha−1, variant 3 – 6.53 t.ha−1, variant 4 – 6.50 t.ha−1. The obtained results indicate that in these pedo-climatic conditions reduction of intensity soil tillage represented a very suitable alternative in case of growing spring barley after sugar beet as compared with the conventional method of tillage by ploughing to the depth of 0.22 m.

  14. Effect of blade vibration on mulch tillage performance under silt clay loam soil

    Directory of Open Access Journals (Sweden)

    B Goudarzi

    2015-09-01

    Full Text Available Introduction: Mulch tillage system is an intermediate system which covers some of disadvantages of no tillage and conventional tillage systems. In farms in which tillage is done with a chisel plow, runoff and soil erosion have a less important relation to moldboard and disk plow and naturally absorption of rainfall will be developed. Thus, the mulch tillage system is an appropriate alternative to conventional tillage and no tillage (Backingham and Pauli, 1993. The unwanted vibration in machinery and industry mainly processes most harmful factors, for example: bearing wear, cracking and loosening joints. And noise is produced in electrical systems by creating a short circuit (Wok, 2011. Self-induced and induced vibration are used in tillage systems. Induced vibration is created by energy consumption and self-induced vibration is created by collision among the blades and soil at the shank (Soeharsono and Setiawan, 2010. A study by Mohammadi-gol et al. (2005 was conducted. It was found that on the disk plow, plant residues maintained on the soil are more than that of moldboard plow. 99% frequency and amplitude, speed and rack angle of blade directly affect soil inversion and indirectly affect preservation of crop residue on the soil. The effect of vibration frequency and rack angle of blade to reduce the tensile strength is also clear. Moreover, in contrast to previous studies when speed progressing is less than (λ, not only the relative speed (λ, but also frequency can reduce the tensile strength (Beiranvand and Shahgoli, 2010; Awad-Allah et al., 2009. Therefore, aim of this study was to determine the effect of vibration and the speed of tillage on soil parameters and drawbar power in using electric power. Materials and Methods: To perform this test, three different modes of vibration (fixed, variable and induced vibration and two levels of speed in real terms at a depth of 20 cm were used for farming. The test was performed with a split plot

  15. [Effects of Long-term Different Tillage Methods on Mercury and Methylmercury Contents in Purple Paddy Soil and Overlying Water].

    Science.gov (United States)

    Wang, Xin-yue; Tang, Zhen-ya; Zhang, Cheng; Wang, Yong-min; Wang, Ding-yong

    2016-03-15

    A long-term experiment was conducted to evaluate the effect of tillage methods on mercury and methylmercury contents in the purple paddy soil and overlying water. The experiment included five tillage methods: no-tillage and fallow in winter, ridge-no-tillage, compartments-no-tillage, paddy-upland rotation and conventional tillage. The results showed that the content of total mercury in soil had the maximum value in the 10-20 cm layer of no-tillage and fallow in winter, ridge-no-tillage and compartments-no-tillage, and the enrichment effect of no-tillage and fallow in winter was especially significant. The concentration of total mercury in soil of paddy-upland rotation and conventional tillage decreased with the increase of the soil depth, and paddy-upland rotation was specifically beneficial to the migration of mercury. The distribution of soil methylmercury was similar to that of total mercury in the soil profile. The methylation ability of soil mercury in the surface and middle of the soil profile was weaker than that at the bottom, while there was an opposite trend for other tillage methods. The concentrations of dissolved mercury ( DHg) and dissolved methylmercury ( DMeHg) in the overlaying water declined with the rise of the water depth in all treatments. The content of DHg in sediment porewater was related to the value of soil total mercury, and they had the same distribution in the soil profile. The content of DMeHg and its proportion accounted for DHg in porewater owned their largest value in the 10-20 cm layer of no-tillage and fallow in winter and ridge-no-tillage, where showed the lowest value of DMeHg in porewater for paddy-upland rotation and conventional tillage. And the percentage of DMeHg in DHg in porewater grew with the increase of soil depth of the latter two methods. Noticeably, the concentration of DMeHg and its proportion accounted for DHg in porewater were both higher than the values in overlying water for all tillage methods.

  16. Effect of tillage system on yield and weed populations of soybean ( Glycin Max L.).

    Science.gov (United States)

    Hosseini, Seyed Z; Firouzi, Saeed; Aminpanah, Hashem; Sadeghnejhad, Hamid R

    2016-03-01

    Field experiment was conducted at Agricultural and Natural Resources Research Center of Golestan Province, Iran, to determine the effects of tillage system and weed management regime on yield and weed populations in soybean ( Glycin max L.). The experimental design was a split plot where the whole plot portion was a randomized complete block with three replicates. Main plots were tillage system: 1- No-till row crop seeding, 2- No-till seed drilling, 3- Tillage with disc harrow and drill planting, 4- Tillage with chisel packer and drill planting. The subplots were weed management regimes: 1-Weed control with herbicide application, 2- Hand weeding, 3- Herbicide application plus hand weeding, and 4- Non-weeding. Results indicated that the main effects of tillage system and weed management regime were significant for seed yield, pod number per plant, seed number per pod, weed density and biomass, while their interaction were significant only for weed density, weed biomass, and seed number per pod. The highest grain yields (3838 kg ha-1) were recorded for No-till row crop seeding. The highest seed yield (3877 kg ha-1) also was recorded for weed control with herbicide and hand weeding treatment, followed by hand weeding (3379 kg ha-1).

  17. Effect of tillage system on yield and weed populations of soybean ( Glycin Max L.

    Directory of Open Access Journals (Sweden)

    Seyed Z. Hosseini

    2016-03-01

    Full Text Available Field experiment was conducted at Agricultural and Natural Resources Research Center of Golestan Province, Iran, to determine the effects of tillage system and weed management regime on yield and weed populations in soybean ( Glycin max L.. The experimental design was a split plot where the whole plot portion was a randomized complete block with three replicates. Main plots were tillage system: 1- No-till row crop seeding, 2- No-till seed drilling, 3- Tillage with disc harrow and drill planting, 4- Tillage with chisel packer and drill planting. The subplots were weed management regimes: 1-Weed control with herbicide application, 2- Hand weeding, 3- Herbicide application plus hand weeding, and 4- Non-weeding. Results indicated that the main effects of tillage system and weed management regime were significant for seed yield, pod number per plant, seed number per pod, weed density and biomass, while their interaction were significant only for weed density, weed biomass, and seed number per pod. The highest grain yields (3838 kg ha-1 were recorded for No-till row crop seeding. The highest seed yield (3877 kg ha-1 also was recorded for weed control with herbicide and hand weeding treatment, followed by hand weeding (3379 kg ha-1.

  18. [Effects of tillage rotation and fertilization on soil aggregates and organic carbon content in corn field in Weibei Highland].

    Science.gov (United States)

    Wang, Li; Li, Jun; Li, Juan; Bai, Wei-Xia

    2014-03-01

    A field experiment on effects of tillage rotation and fertilization on corn continuous cropping-practiced lands was carried out in Heyang of Shaanxi in 2007-2012. The tillage types included annual rotation of no-tillage and subsoiling (NT-ST), subsoiling and conventional tillage (ST-CT), or conventional tillage and no-tillage (CT-NT), and yearly practice of no tillage (NT-NT), subsoiling (ST-ST) or conventional tillage (CT-CT). The fertilization treatments included balanced fertilization, low-rate fertilization and conventional fertilization, which were separately practiced against the different tillage types. The experiment investigated compositions, mean mass diameters (MWD), geometrical mean diameters (GMD) and fraction dimension numbers (D) of soil aggregates in 0-40 cm soil and contents of organic carbon in 0-60 cm soil. The results indicated that: 1) The increased tillage intensity caused the reduced mechanical stability and content of soil aggregates and increased soil organic carbon loss. No-tillage or tillage rotation increased the MWD, GMD and contents of soil organic carbon and soil aggregates with diameters of more than 0.25 mm, but decreased D. Under the same fertilization treatment, the contents of soil aggregates with diameters of more than 0.25 mm were ranked in the order of NT-NT>NT-ST>NT-CT>ST-ST>CT-ST>CT-CT, and under the same tillage rotations, the soil aggregates were more stable with the balanced or low- rate fertilization than with the conventional fertilization. 2) Mathematical fractal dimension fitting of soil aggregates indicated that the fractal dimension numbers of soil aggregates ranged within 2.247-2.681 by dry sieving and 2.897-2.976 by wet sieving. In 0-30 cm soil, the fractal dimension numbers of soil aggregates were significantly lower under no-tillage or tillage rotation than under conventional tillage, and in 0-40 cm soil, the fractal dimensions of soil aggregates increased with soil depth, and tended to stabilize at the soil

  19. [Effects of Tillage on Distribution of Heavy Metals and Organic Matter Within Purple Paddy Soil Aggregates].

    Science.gov (United States)

    Shi, Qiong-bin; Zhao, Xiu-lan; Chang, Tong-ju; Lu, Ji-wen

    2016-05-15

    A long-term experiment was utilized to study the effects of tillage methods on the contents and distribution characteristics of organic matter and heavy metals (Cu, Zn, Pb, Cd, Fe and Mn) in aggregates with different sizes (including 1-2, 0.25-1, 0.05-0.25 mm and tillage methods including flooded paddy field (FPF) and paddy-upland rotation (PR). The relationship between heavy metals and organic matter in soil aggregates was also analyzed. The results showed that the aggregates of two tillage methods were dominated by 0.05-0.25 mm and tillage methods did not significantly affect the contents of heavy metals in soils, but FPF could enhance the accumulation and distribution of aggregate, organic matter and heavy metals in aggregates with diameters of 1-2 mm and 0.25-1 mm. Correlation analysis found that there was a negative correlation between the contents of heavy metals and organic matter in soil aggregates, but a positive correlation between the amounts of heavy metal and organic matter accumulated in soil aggregates. From the slope of the correlation analysis equations, we could found that the sensitivities of heavy metals to the changes of soil organic matters followed the order of Mn > Zn > Pb > Cu > Fe > Cd under the same tillage. When it came to the same heavy metal, it was more sensitive in PR than in FPF.

  20. Assessment the effects of different tillage methods on chickpea yield and some yield components

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    Abdullah KASAP

    2013-06-01

    Full Text Available This study was carried out to determine the effects of different soil tillage methods on crop yield and some yield components in chickpea cultivation. For this reason, experimental trials were performed in Çayköy and Güzelpınar in Tokat-Kazova during 2008, 2009 and 2010. In this trials Gökçe cultivar of chickpea was used. Six different soil tillage methods were applied which were, mouldboard plough tillage in fall + cultivator in the spring + tooth harrow (Method A, mouldboard plough tillage in spring + cultivator + tooth harrow (Method B, rotary tiller in the spring (Method C, chisel in the spring + disc harrow and slider (Method D, strip tillage with router rotary hoe (Method E and direct seeding (Method F. Trials were set up in completely randomized block design with three replications. The results indicated that the highest average plant and seed yield per square meter was obtained with method A (470.74 g and 260.63 g and followed by method B (459.43 g and 254.18 g and method D (447.82 g and 247.23 g. In terms of factors evaluated; A, B and D methods were superior compared to the other methods.

  1. Effect of reduced herbicide amounts with minimum tillage systems on weed infestation

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    Schwarz, Jürgen

    2016-02-01

    Full Text Available Minimum tillage, mainly soil cultivation without ploughing is used in Germany on 40% of arable land. In a long-term field trial in Dahnsdorf (federal state of Brandenburg, Germany the impact of reduced tillage on weed occurrence is investigated. At the same time reduced herbicide amounts are also tested. The use of glyphosate for seedbed preparation is not always necessary. The former crop rotation (67% cereals or 50% cereals has even seven years later a big influence on the weed occurrence. The weed occurrences are lower for the crop rotation with the former 50% cereals. After four years the minimum tillage shows a larger effect of weed infestation. For the non ploughed variants it is higher. If reduced herbicide amounts are used at the same time the effect will increase even more. Results for Apera spica-venti are similar, although the conditions for germination in autumn are also relevant.

  2. Soil Tillage Conservation and its Effect on Soil Properties Bioremediation and Sustained Production of Crops

    Science.gov (United States)

    Rusu, Teodor; Ioana Moraru, Paula; Muresan, Liliana; Andriuca, Valentina; Cojocaru, Olesea

    2017-04-01

    Soil Tillage Conservation (STC) is considered major components of agricultural technology for soil conservation strategies and part of Sustainable Agriculture (SA). Human action upon soil by tillage determines important morphological, physical-chemical and biological changes, with different intensities and evaluative directions. Nowadays, internationally is unanimous accepted the fact that global climatic changes are the results of human intervention in the bio-geo-chemical water and material cycle, and the sequestration of carbon in soil is considered an important intervention to limit these changes. STC involves reducing the number of tillage's (minimum tillage) to direct sowing (no-tillage) and plant debris remains at the soil surface in the ratio of at least 30%. Plant debris left on the soil surface or superficial incorporated contributes to increased biological activity and is an important source of carbon sequestration. STC restore soil structure and improve overall soil drainage, allowing more rapid infiltration of water into soil. The result is a soil bioremediation, more productive, better protected against wind and water erosion and requires less fuel for preparing the germinative bed. Carbon sequestration in soil is net advantageous, improving the productivity and sustainability. We present the influence of conventional plough tillage system on soil, water and organic matter conservation in comparison with an alternative minimum tillage (paraplow, chisel plow and rotary harrow) and no-tillage system. The application of STC increased the organic matter content 0.8 to 22.1% and water stabile aggregate content from 1.3 to 13.6%, in the 0-30 cm depth, as compared to the conventional system. For the organic matter content and the wet aggregate stability, the statistical analysis of the data showed, increasing positive significance of STC. While the soil fertility and the wet aggregate stability were initially low, the effect of conservation practices on the

  3. The Energy Effectiveness Of Crops In Crop Rotation Under Different Soil Tillage Systems

    Directory of Open Access Journals (Sweden)

    Strašil Zdeněk

    2015-09-01

    Full Text Available The paper identifies and compares the energy balance of winter wheat, spring barley and white mustard – all grown in crop rotation under different tillage conditions. The field trial included the conventional tillage (CT method, minimum tillage (MT and a system with no tillage (NT. The energy inputs included both the direct and indirect energy component. Energy outputs are evaluated as gross calorific value (gross heating value of phytomass dry matter of the primary product and the total harvested production. The energy effectiveness (energy output: energy input was selected for evaluation. The greatest energy effectiveness for the primary product was established as 6.35 for barley, 6.04 for wheat and 3.68 for mustard; in the case of total production, it was 9.82 for barley, 10.08 for wheat and 9.72 for mustard. When comparing the different tillage conditions, the greatest energy effectiveness was calculated for the evaluated crops under the MT operation and represented the primary product of wheat at 6.49, barley at 6.69 and mustard at 3.92. The smallest energy effectiveness for the primary product was found in wheat 5.77 and barley 6.10 under the CT option; it was 3.55 for mustard under the option of NT. Throughout the entire cropping pattern, the greatest energy effectiveness was established under the minimum tillage option – 5.70 for the primary product and 10.47 for the total production. On the other hand, the smallest values were calculated under CT – 5.22 for the primary product and 9.71 for total production.

  4. Effect of tillage practices on soil properties and crop productivity in wheat-mungbean-rice cropping system under subtropical climatic conditions.

    Science.gov (United States)

    Alam, Md Khairul; Islam, Md Monirul; Salahin, Nazmus; Hasanuzzaman, Mirza

    2014-01-01

    This study was conducted to know cropping cycles required to improve OM status in soil and to investigate the effects of medium-term tillage practices on soil properties and crop yields in Grey Terrace soil of Bangladesh under wheat-mungbean-T. aman cropping system. Four different tillage practices, namely, zero tillage (ZT), minimum tillage (MT), conventional tillage (CT), and deep tillage (DT), were studied in a randomized complete block (RCB) design with four replications. Tillage practices showed positive effects on soil properties and crop yields. After four cropping cycles, the highest OM accumulation, the maximum root mass density (0-15 cm soil depth), and the improved physical and chemical properties were recorded in the conservational tillage practices. Bulk and particle densities were decreased due to tillage practices, having the highest reduction of these properties and the highest increase of porosity and field capacity in zero tillage. The highest total N, P, K, and S in their available forms were recorded in zero tillage. All tillage practices showed similar yield after four years of cropping cycles. Therefore, we conclude that zero tillage with 20% residue retention was found to be suitable for soil health and achieving optimum yield under the cropping system in Grey Terrace soil (Aeric Albaquept).

  5. Microbial Biomass Carbon Trends in Black and Red Soils Under Single Straw Application: Effect of Straw Placement, Mineral N Addition and Tillage

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Quantifying trends in soil microbial biomass carbon (SMBC) under contrasting management conditions is important in understanding the dynamics of soil organic matter (SOM) in soils and in ensuring their sustainable use. Against such a background, a 60-day greenhouse simulation experiment was carried out to study the effects of straw placement, mineral N source, and tillage on SMBC dynamics in two contrasting soils, red soil (Ferrasol) and black soil (Acrisol). The treatments included straw addition + buried (T1);straw addition + mineral N (T2); and straw addition + tillage (T3). Straw was either buried in the soil or placed on the surface. Sampling was done every 15 days. Straw placement, addition of external mineral N sources (Urea, 46 % N) and soil type affected SMBC. SMBC levels decreased with exposure durations (15 days, 30 days, 45 days, and 60 days). Rate of SMBC fixation was more in buried straw than in surface placed straw at all sampling dates in both soils. Addition of an external N source significantly increased SMBC level. Soil pH increased in both soil types, with a greater increase in black soil than in red soil. The study could not, however, statistically account for the effect of tillage on SMBC levels because of the limited effect of our tillage method due to the artificial barrier to mechanical interference supplied by the mesh bags,although differences in absolute values were quite evident between treatments T1 and T3.``

  6. Minimum tillage and vegetative barrier effects on crop yields in relation to soil water content in the Central Kenya highlands

    NARCIS (Netherlands)

    Guto, S.N.; Ridder, de N.; Giller, K.E.; Pypers, P.; Vanlauwe, B.

    2012-01-01

    The sub-humid zone of Central Kenya is water deficient due to regular intra-seasonal dry spells that constrain rain-fed crop production. A study was initiated to investigate the effects of minimum tillage and vegetative barriers on soil and water conservation and crop yield. There were two tillage p

  7. Effect of different tillage intensity on yields and yield-forming factors in winter wheat

    Directory of Open Access Journals (Sweden)

    Martin Houšť

    2012-01-01

    Full Text Available The paper presents results of a study on application of minimum tillage technologies when growing winter wheat. Experiments were performed in the sugar-beet-growing region with loamy chernozem within the period of 2005–2009. Aanalysed and evaluated were effects of different methods of soil processing on yield-forming factors in stands of winter wheat grown after three different preceding crops (i.e. alfalfa, maize for silage and pea. Evaluated were the following four variants of tillage: (1 conventional ploughing to the depth of 0.22 m (Variant 1; (2 ploughing to the depth of 0.15 m (Variant 2; (3 direct sowing into the untilled soil (Variant 3, and (4 shallow tillage to the depth of 0.10 m (Variant 4.The effect of different tillage intensity on winter wheat yields was statistically non-significant after all forecrops. After alfalfa, the highest and the lowest average yields were recorded in Variant 2 (i.e. with ploughing to the depth of 0.15 m and Variant 3 (direct sowing into the untilled soil, respectively. After maize grown for silage, higher yields were obtained in Variant 2 and Variant 1 (conventional ploughing while in Variants 4 and 3 the obtained yields were lower. When growing winter wheat after pea as a preceding crop, the highest and the lowest average yields were recorded after direct sowing (Variant 3 and in Variant 1 (i.e. ploughing to the depth of 0.22 m, respectively. Results of studies on effect of different tillage technologies on yields of winter wheat crops indicate that under the given pedological and climatic conditions it is possible to apply methods of reduced tillage intensity. However, the choice of the corresponding technology must be performed with regard to the type of preceding crop.

  8. [Effects of long-term tillage and rice straw returning on soil nutrient pools and Cd concentration].

    Science.gov (United States)

    Tang, Wen-guang; Xiao, Xiao-ping; Tang, Hai-ming; Zhang, Hai-lin; Chen, Fu; Chen, Zhong-du; Xue, Jian-fu; Yang, Guang-li

    2015-01-01

    The objective of this study was to assess the effects of tillage and straw returning on soil nutrient and its pools, and soil Cd concentration, and to identify the strategies for rational tillage and remediation of Cd contaminated paddy fields. The experiment was established with no-tillage with straw retention (NTS) , rotary tillage with straw incorporation (RTS) , conventional plow tillage with straw incorporation (CTS), conventional plow tillage with straw removed ( CT) from 2005 to 2013. The results indicated that tillage and rice straw retention had a great impact on soil properties at 0-10 cm soil depth. The soil aeration, and concentrations of soil nutrient and soil Cd increased under CTS, CT, and RTS. Due to the shallow plow layers, soil nutrient pools and the Cd concentration in rice shoot decreased in long-term tilled soil. Under long-term no-tillage, the soil bulk, soil nutrient pools and Cd concentration in rice shoot increased, but concentrations of soil nutrients decreased. In addition, rice straw returning significantly increased the soil nutrient concentrations, cation exchange capacity, depth of plow layer, and soil nutrient pools. However, the Cd in the rice straw was also returned to the soil by rice straw returning, which would not benefit the remediation of soil Cd. Therefore, it is necessary to improve tillage and straw retention practices due to the disadvantages of long-term continuous single tillage method and rice straw returning practices. Some recommended managements (e.g., rotational tillage or subsoiling, reducing straw returning amount, and rotational straw returning) could be good options in enhancing soil fertility and remedying soil pollution.

  9. Assessing Tillage Effects on Soil Hydraulic Properties via Inverse Parameter Estimation using Tension Infiltrometry

    Science.gov (United States)

    Schwen, Andreas; Bodner, Gernot; Loiskandl, Willibald

    2010-05-01

    Hydraulic properties are key factors controlling water and solute movement in soils. While several recent studies have focused on the assessment of the spatial variability of hydraulic properties, the temporal dynamics are commonly not taken into account, primarily because its measurement is costly and time-consuming. However, there is extensive empirical evidence that these properties are subject to temporal changes, particularly in the near-saturated range where soil structure strongly influences water flow. One main source of temporal variability is soil tillage. It can improve macroporosity by loosening the soil and thereby changing the pore-size distribution. Since these modifications are quite unstable over time, the pore space partially collapses after tillage. This effect should be largest for conventional tillage (CT), where the soil is ploughed after harvest every year. Assessing the effect of different tillage treatments on the temporal variability of hydraulic properties requires adequate measurement techniques. Tension infiltrometry has become a popular and convenient method providing not only the hydraulic conductivity function but also the soil rentention properties. The inverse estimation of parameters from infiltration measurements remains challenging, despite some progress since the first approach of Šimůnek et al. (1998). Measured data like the cumulative infiltration, the initial and final volumetric water content, as well as independently measured retention data from soil core analysis with laboratory methods, have to be considered to find an optimum solution describing the soil's pore space. In the present study we analysed tension infiltration measurements obtained several times between August 2008 and December 2009 on an arable field in the Moravian Basin, Lower Austria. The tillage treatments were conventional tillage including ploughing (CT), reduced tillage with chisel only (RT), and no-tillage treatment using a direct seeding

  10. Tillage Management and Seasonal Effects on Denitrifier Community Abundance, Gene Expression and Structure over Winter.

    Science.gov (United States)

    Tatti, Enrico; Goyer, Claudia; Burton, David L; Wertz, Sophie; Zebarth, Bernie J; Chantigny, Martin; Filion, Martin

    2015-10-01

    Tillage effects on denitrifier communities and nitrous oxide (N2O) emissions were mainly studied during the growing season. There is limited information for the non-growing season, especially in northern countries where winter has prolonged periods with sub-zero temperatures. The abundance and structure of the denitrifier community, denitrification gene expression and N2O emissions in fields under long-term tillage regimes [no-tillage (NT) vs conventional tillage (CT)] were assessed during two consecutive winters. NT exerted a positive effect on nirK and nosZ denitrifier abundance in both winters compared to CT. Moreover, the two contrasting managements had an opposite influence on nirK and nirS RNA/DNA ratios. Tillage management resulted in different denitrifier community structures during both winters. Seasonal changes were observed in the abundance and the structure of denitrifiers. Interestingly, the RNA/DNA ratios were greater in the coldest months for nirK, nirS and nosZ. N2O emissions were not influenced by management but changed over time with two orders of magnitude increase in the coldest month of both winters. In winter of 2009-2010, emissions were mainly as N2O, whereas in 2010-2011, when soil temperatures were milder due to persistent snow cover, most emissions were as dinitrogen. Results indicated that tillage management during the growing season induced differences in denitrifier community structure that persisted during winter. However, management did not affect the active cold-adapted community structure.

  11. Adoption of Maize Conservation Tillage in Azuero, Panama

    OpenAIRE

    de Herrera, Adys Pereira; Sain, Gustavo

    1999-01-01

    An aggressive research and validation program launched in 1984 in Azuero, Panama, yielded a recommendation advocating zero tillage for maize production. Ten years later, maize farmers in Azuero used three land preparation methods: conventional tillage, zero tillage, and minimum tillage (an adaptation of the zero tillage technology). This study aimed to quantify the adoption of zero and minimum tillage for maize in Azuero; identify factors influencing adoption of the different land preparation...

  12. [Effects of conservation tillage on soil CO2 and N2O emission during the following winter-wheat season].

    Science.gov (United States)

    Pan, Ying; Hu, Zheng-Hu; Wu, Yang-Zhou; Sun, Yin-Yin; Sheng, Lu; Chen, Shu-Tao; Xiao, Qi-Tao

    2014-07-01

    In order to study the effect of conservation tillage on soil CO2 and N2O emissions in the following crop-growing season, field experiments were conducted in the winter wheat-growing season. Four treatments were conventional tillage (T), no-tillage with no straw cover (NT), no-tillage with straw cover (NTS), and conventional tillage with straw incorporation (TS), respectively. The CO2 and N2O fluxes were measured using a static chamber-gas chromatograph technique. The results showed that in the following winter wheat-growing season, conservation tillage did not change the seasonal pattern of CO2 and N2O emission fluxes from soil, and had no significant effect on crop biomass. Conservation tillage significantly reduced the accumulative amount of CO2 and N2O. Compared with the T treatment, the accumulative amount of CO2 under TS, NT, and NTS treatments were reduced by 5.95% (P = 0.132), 12.94% (P = 0.007), and 13.91% (P = 0.004), respectively, and the accumulative amount of N2O were significantly reduced by 31.23% (P = 0.000), 61.29% (P = 0.000), and 33.08% (P = 0.000), respectively. Our findings suggest that conservation tillage significantly reduced CO2 and N2O emission from soil in the following winter wheat-growing season.

  13. Effects of crop rotation and soil tillage on weeds in organic farming

    Directory of Open Access Journals (Sweden)

    Schulz, Franz

    2014-02-01

    Full Text Available An organic long-term field experiment with two factors has been carried out since 1998 at the experimental station Gladbacherhof, University of Giessen. Effects of 3 different farm types (with lifestock raising, stockless farming with rotational set-aside, stockless farming only cash crops combined with 4 tillage treatments (mouldboard plough, two-layer-plough, reduced tillage depth and tillage without plough on plants, soil and environment have been investigated. This article presents results on the coverage rate of arable wild plants (weed coverage, the range of weed species, the abundance of C. arvense (L. Scop. (Canada thistle and the weed phytomass during harvest time of the main crops dependent on farm type and soil tillage. It can be concluded that, compared to conventional economic weed thresholds, the weed coverage was generally relatively low and only limited ranges of species were found. Wild arable plants probably did not have any impact on yields of the cultivated plants due to intensive mechanical regulatory measures. In stockless organic farming without alfalfa-grass in the crop rotation Cirsium arvense (L. Scop. (Canada thistle might become a problem whereas this perennial root-weed does not seem to raise a long term problem in a soil tillage system without ploughing. In all treatments the abundance of weeds like Galium aparine L. (catchweed bedstraw and Stellaria media L. (chickweed was high. However, none of the farm types or soil tillage systems succeeded in providing evidence of promoting rare species or encouraging biodiversity. In order to achieve this special support measures should be implemented.

  14. Effect of Rotational Tillage on Soil Aggregates, Organic Carbon and Nitrogen in the Loess Plateau Area of China

    Institute of Scientific and Technical Information of China (English)

    HOU Xian-Qing; LI Rong; JIA Zhi-Kuan; HAN Qing-Fang

    2013-01-01

    In rain-fed semi-arid agroecosystems,continuous conventional tillage can cause serious problems in soil quality and crop production,whereas rotational tillage (no-tillage and subsoiling) could decrease soil bulk density,and increase soil aggregates and organic carbon in the 0-40 cm soil layer.A 3-year field study was conducted to determine the effect of tillage practices on soil organic carbon (SOC),total nitrogen (TN),water-stable aggregate size distribution and aggregate C and N sequestration from 0 to 40 cm soil in semi-arid areas of southern Ningxia.Three tillage treatments were tested:no-tillage in year 1,subsoiling in year 2,and no-tillage in year 3 (NT-ST-NT); subsoiling in year 1,no-tillage in year 2,and subsoiling in year 3 (ST-NT-ST); and conventional tillage over years 1-3 (CT).Mean values of soil bulk density in 0-40 cm under NT-ST-NT and ST-NT-ST were significantly decreased by 3.3% and 6.5%,respectively,compared with CT,while soil total porosity was greatly improved.Rotational tillage increased SOC,TN,and water-stable aggregates in the 0-40 cm soil,with the greatest effect under ST-NT-ST.In 0-20 and 20-40 cm soils,the tillage effect was confined to the 2-0.25 mm size fraction of soil aggregates,and rotational tillage treatments obtained significantly higher SOC and TN contents than conventional tillage.No significant differences were detected in SOC and TN contents in the > 2 mm and < 0.25 mm aggregates among all treatments.In conclusion,rotational tillage practices could significantly increase SOC and TN levels,due to a fundamental change in soil structure,and maintain agroecosystem sustainability in the Loess Plateau area of China.

  15. [Effects of tillage conversion on carbon sequestration capability of farmland soil doubled cropped with wheat and corn].

    Science.gov (United States)

    Han, Bin; Kong, Fan-Lei; Zhang, Hai-Lin; Chen, Fu

    2010-01-01

    By the methods of field experiment, laboratory analysis, and in situ investigation, this paper studied the effects of different tillage conversion on the carbon sequestration capability of farmland soil doubled cropped with wheat and corn. Compared with conventional tillage (CTA), conservation tillage practices benefited the accumulation of soil organic carbon, among which, no-tillage plus straw returning (NTS) increased the organic carbon accumulation in 0-5 cm soil layer by 18.0%, rotary tillage plus straw returning (RTS) increased this accumulation in 0-5 and 5-10 cm soil layers by 17.6% and 25.0%, respectively, and conventional tillage plus straw returning (CTS) increased the organic carbon in 10-30 cm soil layer by 31.8%. After the conversion from CTA to NTS, the carbon emission from farm operations decreased by 54.3 kg x hm(-2) x a(-1); while the conversion from CTA to CTS and RTS resulted in an increase of this emission by 46.9 kg x hm(-2) x a(-1) and 34.4 kg x hm(-2) x a(-1), respectively. Considering of the accumulation of soil organic carbon and the carbon emission from farm operations, it could be concluded that the conversion from CTA to conservation tillage changed this farmland soil from carbon source to carbon sink, and the RTS among the three conservation tillage modes resulted in the highest soil carbon sequestration (1011.1 kg x hm(-2) x a(-1)).

  16. Effects of different tillage and straw return on soil organic carbon in a rice-wheat rotation system.

    Science.gov (United States)

    Zhu, Liqun; Hu, Naijuan; Yang, Minfang; Zhan, Xinhua; Zhang, Zhengwen

    2014-01-01

    Soil management practices, such as tillage method or straw return, could alter soil organic carbon (C) contents. However, the effects of tillage method or straw return on soil organic C (SOC) have showed inconsistent results in different soil/climate/cropping systems. The Yangtze River Delta of China is the main production region of rice and wheat, and rice-wheat rotation is the most important cropping system in this region. However, few studies in this region have been conducted to assess the effects of different tillage methods combined with straw return on soil labile C fractions in the rice-wheat rotation system. In this study, a field experiment was used to evaluate the effects of different tillage methods, straw return and their interaction on soil total organic C (TOC) and labile organic C fractions at three soil depths (0-7, 7-14 and 14-21 cm) for a rice-wheat rotation in Yangzhong of the Yangtze River Delta of China. Soil TOC, easily oxidizable C (EOC), dissolved organic C (DOC) and microbial biomass C (MBC) contents were measured in this study. Soil TOC and labile organic C fractions contents were significantly affected by straw returns, and were higher under straw return treatments than non-straw return at three depths. At 0-7 cm depth, soil MBC was significantly higher under plowing tillage than rotary tillage, but EOC was just opposite. Rotary tillage had significantly higher soil TOC than plowing tillage at 7-14 cm depth. However, at 14-21 cm depth, TOC, DOC and MBC were significantly higher under plowing tillage than rotary tillage except for EOC. Consequently, under short-term condition, rice and wheat straw both return in rice-wheat rotation system could increase SOC content and improve soil quality in the Yangtze River Delta.

  17. Effects of different tillage and straw return on soil organic carbon in a rice-wheat rotation system.

    Directory of Open Access Journals (Sweden)

    Liqun Zhu

    Full Text Available Soil management practices, such as tillage method or straw return, could alter soil organic carbon (C contents. However, the effects of tillage method or straw return on soil organic C (SOC have showed inconsistent results in different soil/climate/cropping systems. The Yangtze River Delta of China is the main production region of rice and wheat, and rice-wheat rotation is the most important cropping system in this region. However, few studies in this region have been conducted to assess the effects of different tillage methods combined with straw return on soil labile C fractions in the rice-wheat rotation system. In this study, a field experiment was used to evaluate the effects of different tillage methods, straw return and their interaction on soil total organic C (TOC and labile organic C fractions at three soil depths (0-7, 7-14 and 14-21 cm for a rice-wheat rotation in Yangzhong of the Yangtze River Delta of China. Soil TOC, easily oxidizable C (EOC, dissolved organic C (DOC and microbial biomass C (MBC contents were measured in this study. Soil TOC and labile organic C fractions contents were significantly affected by straw returns, and were higher under straw return treatments than non-straw return at three depths. At 0-7 cm depth, soil MBC was significantly higher under plowing tillage than rotary tillage, but EOC was just opposite. Rotary tillage had significantly higher soil TOC than plowing tillage at 7-14 cm depth. However, at 14-21 cm depth, TOC, DOC and MBC were significantly higher under plowing tillage than rotary tillage except for EOC. Consequently, under short-term condition, rice and wheat straw both return in rice-wheat rotation system could increase SOC content and improve soil quality in the Yangtze River Delta.

  18. Effect of Tillage on Soil Properties and Yield of Sorghum ( Sorghum ...

    African Journals Online (AJOL)

    Effect of Tillage on Soil Properties and Yield of Sorghum ( Sorghum Bicolor (L.) ... second and third experiments and selected soil physical properties were determined. ... Soil pH, organic matter, N, P, K, Ca and Mg were significantly influenced ...

  19. Emissions of nitrous oxide from Irish arable soils: effects of tillage and reduced N input

    DEFF Research Database (Denmark)

    Abdalla, M.; Jones, M.B.; Ambus, Per;

    2010-01-01

    . Reduced tillage had no significant effect on N2O fluxes from soils or crop grain yield. Multiple regression analysis revealed that soil moisture and an interaction between soil moisture and soil nitrate are the main significant factors affecting N2O flux. The derived emission factor was 0...

  20. Tillage effects on physical qualities of a vertisol in the central ...

    African Journals Online (AJOL)

    user

    evaluated for their effects on soil physical quality indicators. The study was .... Control. This is the traditional tillage practice known as ridge and furrows. (RFs) used .... kPa and 1500 kPa ceramic plates was used to determine soil water content ...

  1. One-time tillage of no-till: Effects on nutrients, mycorrhizae, and phosphorus uptake

    Science.gov (United States)

    Stratification of nutrient availability, especially of P, that develops with continuous no-till (NT) can affect runoff nutrient concentration and possibly nutrient uptake. The effects of composted manure application and one-time tillage of NT on the distribution of soil chemical properties, root co...

  2. [Effects of rotational tillage during summer fallow on wheat field soil water regime and grain yield].

    Science.gov (United States)

    Hou, Xian-qing; Wang, Wei; Han, Qing-fang; Jia, Zhi-kuan; Yan, Bo; Li, Yong-ping; Su, Qin

    2011-10-01

    In 2007-2010, a field experiment was conducted to study the effects of different rotational tillage practices during summer follow on the soil water regime and grain yield in a winter wheat field in Southern Ningxia arid area. Three treatments were installed, i.e., T1 (no-tillage in first year, subsoiling in second year, and no-tillage in third year), T2 (subsoiling in first year, notillage in second year, and subsoiling in third year), and CT (conventional tillage in the 3 years). Through the three years of the tillage practices, the soil water storage efficiency in treatments T1 and T2 was increased averagely by 15.2% and 26.5%, respectively, as compared to CT. In treatments T1 and T2, the potential rainfall use rate was higher, being 37.8% and 38.5%, respectively, and the rainfall use efficiency was increased averagely by 9.9% and 10.7%, respectively, as compared to CT. Rotational tillage during summer fallow could decrease the soil ineffective evaporation significantly, and save the soil water effectively in wheat growth season. At early growth stage, the water storage in 0-200 cm soil layer in treatments T1 and T2 was increased averagely by 6.8% and 9. 4%, as compared to CT; at jointing, heading, and filling stages, the water storage in 0-200 cm soil layer in treatments T1 and T2 had a significant increase, giving greater contribution to the wheat yield than the control. Different rotational tillage practices increased the water consumption by wheat, but in the meantime, increased the grain yield and water use efficiency. In treatments T1 and T2, the water consumption by wheat through the three years was increased averagely by 5.2% and 6.1%, whereas the grain yield and the water use efficiency were increased averagely by 9.9% and 10.6%, and by 4.5% and 4.3%, respectively, as compared to CT. Correlation analysis showed that in Southern Ningxia arid area, the soil water storage at sowing, jointing, heading, and filling stages, especially at heading stage, could

  3. Effect of tillage and planting date on seasonal abundance and diversity of predacious ground beetles in cotton.

    Science.gov (United States)

    Shrestha, R B; Parajulee, M N

    2010-01-01

    A 2-year field study was conducted in the southern High Plains region of Texas to evaluate the effect of tillage system and cotton planting date window on seasonal abundance and activity patterns of predacious ground beetles. The experiment was deployed in a split-plot randomized block design with tillage as the main-plot factor and planting date as the subplot factor. There were two levels for each factor. The two tillage systems were conservation tillage (30% or more of the soil surface is covered with crop residue) and conventional tillage. The two cotton planting date window treatments were early May (normal planting) and early June (late planting). Five prevailing predacious ground beetles, Cicindela sexguttata F., Calosoma scrutator Drees, Pasimachus spp., Pterostichus spp., and Megacephala Carolina L. (Coleoptera: Carabidae), were monitored using pitfall traps at 2-week intervals from June 2002 to October 2003. The highest total number of ground beetles (6/trap) was observed on 9 July 2003. Cicindela sexguttata was the dominant ground dwelling predacious beetle among the five species. A significant difference between the two tillage systems was observed in the abundances of Pterostichus spp. and C. sexguttata. In 2002. significantly more Pterostichus spp. were recorded from conventional plots (0.27/trap) than were recorded from conservation tillage plots (0.05/trap). Significantly more C. sexguttata were recorded in 2003 from conservation plots (3.77/trap) than were recorded from conventional tillage plots (1.04/trap). There was a significant interaction between year and tillage treatments. However, there was no significant difference in the abundances of M. Carolina and Pasimachus spp. between the two tillage practices in either of the two years. M. Carolina numbers were significantly higher in late-planted cotton compared with those observed in normal-planted cotton. However, planting date window had no significant influence on the activity patterns of the

  4. [Diversity of soil fauna in corn fields in Huang-Huai-Hai Plain of China under effects of conservation tillage].

    Science.gov (United States)

    Zhu, Qiang-Gen; Zhu, An-Ning; Zhang, Jia-Bao; Zhang, Huan-Chao; Huang, Ping; Zhang, Cong-Zhi

    2009-10-01

    An investigation was made on the abundance and diversity of soil fauna in the corn fields under conventional and conservation tillage in Huang-Huai-Hai Plain of China. The abundance and diversity of soil fauna were higher at corn maturing (September) than at its jointing stage (July), and higher at jointing stage under conservation tillage than under conventional tillage. Soil fauna mainly distributed in surface soil layer (0-10 cm), but still had a larger number in 10-20 cm layer under conservation tillage. The individuals of acari, diptera, diplura, and microdrile oligochaetes, especially those of acari, were higher under conservation tillage than under conventional tillage. At maturing stage, an obvious effect of straw-returning under conservation tillage was observed, i. e., the more the straw returned, the higher the abundance of soil fauna, among which, the individuals of collembola, acari, coleopteran, and psocoptera, especially those of collembolan, increased significantly. The abundance of collembola at both jointing and maturing stages was significantly positively correlated with the quantity of straw returned, suggesting that collembola played an important role in straw decomposition and nutrient cycling.

  5. [Long-term effects of tillage methods on heavy metal accumulation and availability in purple paddy soil].

    Science.gov (United States)

    Chang, Tong-Ju; Cui, Xiao-Qiang; Ruan, Zhen; Zhao, Xiu-Lan

    2014-06-01

    A long-term experiment, conducted at Southwest University since 1990, was used to evaluate the effect of tillage methods on the total and available contents of heavy metals (Fe, Mn, Cu, Zn, Pb, Cd) in the profile of purple paddy soil and the contents of those metals in root, stem leaf and brown rice. The experiment included five tillage methods: conventional tillage, paddy-upland rotation, no-tillage and fallow in winter, ridge-no-tillage and compartments-no-tillage. The results showed that the total concentrations of Fe, Cu, Zn, Pb and Cd in the soil profile had no significant differences among five treatments, but it was found that total Mn has a significant decline in 0-20 cm under conventional tillage, paddy-upland rotation and no-tillage and fallow in winter compared with ridge-no-tillage and compartments-no-tillage. The availability of Fe, Cu, Zn, Pb and Cd decreased with the increase of soil depth in all treatments, but the availability of Mn was found to be the highest in the 20-40 cm layers except those in the paddy-upland rotation. In the ploughed layer, the contents of available Fe, Mn was the highest in paddy-upland rotation, while the contents of available Zn and Pb was the highest in conventional tillage, but tillage treatments had not significant influence to the contents of available Cu. Correlation analysis showed that available Fe was significantly negatively related to the pH values and significantly negatively related to the organic matter of soils, available Mn was significantly negatively related to the pH values and organic matter of soils, whereas the available Zn was significantly positively related to total Zn. The contents of Fe, Mn in rice root, the contents of Fe, Mn, Cu and Cd in rice straw and Cu in brown rice were higher under paddy-upland rotation, ridge-no-tillage and compartments-no-tillage than those in conventional tillage and no-tillage and fellow in winter. Paddy-upland rotation can significantly lower the migration

  6. The effect of various long-term tillage systems on soil properties and spring barley yield

    OpenAIRE

    MALECKA, Irena; Blecharczyk, Andrzej; SAWINSKA, Zuzanna; DOBRZENIECKI, Tomasz

    2012-01-01

    This study, performed on a soil that is classified as Albic Luvisols that developed on loamy sands overlying loamy material (1.4% organic matter and pH 6.5), concerns the impact of tillage systems on soil properties and the yield of spring barley. The experiment design included 3 tillage systems: conventional tillage, reduced tillage, and no-tillage. Continuous cultivation for 7 consecutive years by reduced tillage and no-tillage led to changes in the physical properties of the surface soil l...

  7. Effect of Cropping System and Contouring or Download Sowing on Soil Water Erosion under no Tillage

    Science.gov (United States)

    Marioti, J.; Padilha, J.; Bertol, I.; Barbosa, F. T.; Ramos, J. C.; Werner, R. S.; Vidal Vázquez, E.; Tanaka, M. S.

    2012-04-01

    Water erosion is the main responsible factor of soil and water losses, thus also causing soil degradation, especially on agricultural land, and it is also one factor of degradation outside the place of the origin of erosion. No tillage agriculture has been practiced in the last few decades for the purposes of water erosion control in various regions of Brazil. However, it has been shown that no tillage does not adequately control water erosion unless other complementary conservationist practices such as contour tillage or terracement. Although the erosion problem is widely recognized, there are still difficulties in estimating their magnitude, the environmental impact and the economic consequences, especially when it occurs in a conservation system like no tillage. The aim of this study was to quantify runoff and soil losses by water erosion under five different soil tillage treatments at Santa Catarina State, Southern Brazil. A field study was carried out using a rotating-boom rainfall simulator with 64 mmh-1 rainfall intensity for 90 minutes. Four rainfall tests were applied over the experimental period, one in each of the successive soybean and maize crop stages. Both soil cover by surface crop residue and soil cover by soybean and maize plant canopy were measured immediately before each rainfall test. Soil and water losses were smaller when sowing in contour than when sowing downslope. Contouring has promoted an average reduction of 42% in soil losses and 20% in water losses. Maize crop has promoted an average reduction of 19% in soil losses and 12% in water losses, in relation to the soybean crop. Therefore runoff rates and soil losses were higher in the downslope plots and in the soybean crop. Soil cover by previous crop residue was an important factor for reducing soil losses. Runoff rates were influenced by the soil water content before each rainfall test (R2= 0.78). The highest runoff occurred during the third simulated rainfall test, with the 83% of the

  8. Short-term Effects of Tillage Practices on Organic Carbon in Clay Loam Soil of Northeast China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A tillage experiment, consisting of moldboard plow (MP), ridge tillage (RT), and no-tillage (NT), was performed in a randomized complete block design with four replicates to study the effect of 3-year tillage management on SOC content and its distribution in surface layer (30 cm) of a clay loam soil in northeast China. NT did not lead to significant increase of SOC in topsoil (0-5 cm) compared with MP and RT; however, the SOC content in NT soil was remarkably reduced at a depth of 5-20 cm. Accordingly, short-term (3-year) NT management tended to stratify SOC concentration, but not necessarily increase its storage in the plow layer for the soil.

  9. [Effects of tillage in fallow period on soil water and nitrogen absorption and translocation by wheat plant].

    Science.gov (United States)

    Ren, Ai-Xia; Sun, Min; Zhao, Wei-Feng; Deng, Lian-Feng; Deng, Yan; Gao, Zhi-Qiang

    2013-12-01

    Field test was carried out to study the effect of tillage in fallow period on soil water before sowing and growth stages, and nitrogen (N) absorption, translocation by wheat plant. The current data showed that tillage in fallow period improved the soil water at the depth of 0-300 cm before sowing and growth stages, especially in dry years. Such tillage significantly improved N accumulation in leaf, stem and sheath (SS) at anthesis, grain N accumulation at maturity, N mobilization in SS and the contribution of mobilized N to grain N, amount of mobilized N in leaf, level of N accumulation before anthesis, N transportation from vegetative organs to grains after anthesis, and nitrogen accumulation after anthesis, which in turn enhanced the efficiency of N uptake. Deep tillage at 45 days after harvest had the best effect. Significant correlations were detected between soil water and N accumulation before anthesis as well as N translation from vegetative organs grains after anthesis, particularly in dry years, while the correlation between soil water from sowing to an thesis and nitrogen accumulation amount after anthesis was significant in wet years, but not in dry years. Tillage in fallow period especially deep tillage after raining could benefit soil water preservation, as well as N absorption and translocation by plant.

  10. Effect of tillage system on distribution of aggregates and organic carbon in a hydragric anthrosol

    Institute of Scientific and Technical Information of China (English)

    GAO Ming; LUO You-Jin; WANG Zi-Fang; TANG Xiao-Hong; WEI Chao-Fu

    2008-01-01

    The effect of different tillage systems on the size distribution of aggregates and organic carbon distribution and storage in different size aggregates in a Hydragric Anthrosol were studied in a long-term experiment in Chongqing,China.The experiment included three tillage treatments:conventional tillage with rotation of rice and winter fallow (CT-r) system,no-till and ridge culture with rotation of rice and rape (RT-rr) system,and conventional tillage with rotation of rice and rape (CT-rr) system.The results showed that the aggregates 0.02-0.25 mm in diameter accounted for the largest portion in each soil layer under all treatments.Compared with the CT-r system,in the 0-10 cm layer,the amount of aggregates>0.02 mm was larger under the RT-rr system,but smaller under the CT-rr system.In the 0-20 cm layer,the organic carbon content of all fractions of aggregates was the highest under the RT-rr system and lowest under the CT-rr system.The total organic carbon content showed a positive linear relationship with the amount of aggregates with diameter ranging from 0.25 to 2 ram.The storage of organic carbon in all fractions of aggregates under the RT-rr system was higher than that under the CT-r system in the 0-20 cm layer,but in the 0-60 cm soil layer,there was no distinct difference.Under the CT-rr system,the storage of organic carbon in all fractions of aggregates was lower than that under the CT-r system;most of the newly lost organic carbon was from the aggregates 0.002-0.02 and 0.02-0.25 mm in diameter.

  11. TILLAGE EFFECTS ON SUNFLOWER (HELIANTHUS ANNUUS, L. EMERGENCE, YIELD, QUALITY, AND FUEL CONSUMPTION IN DOUBLE CROPPING SYSTEM

    Directory of Open Access Journals (Sweden)

    ABDULLAH SESSIZ

    2009-06-01

    Full Text Available The relation between crop growing and soil tillage treatment are play important role in agricultural production. Soils under conventional tillage (CT generally have lower bulk density and associated higher total porosity within the plough layer than under no tillage (NT. No-till farming can reduce soil erosion, conserve soil moisture and minimize labor and fuel consumption. The aim of this study were to investigate the effects of conventional, reduced and notillage methods on soil physical properties, sunfl ower yield and yield components, protein and oil content and fuel consumption in Southeastern of Turkey. Six tillage methods for the second crop sunfl ower were tested and compared each other within after lentil harvesting at 2003 and 2004 years in a clay loam soil. According to results, the fi rst year, the bulk density had decreased from 1.29 to 1.09 g cm-3, the second year the δb had decreased from 1.41 to 1.23 g cm-3. Differences between years and tillage methods in terms of yield were found signifi cant (p<0.05. However, no differences were found between the NT and CT. There were also no signifi cance differences in content of protein, oil and ash among six tillage methods. The highest fuel consumption was measured in conventional method (CT whereas the lowest value was found in direct seeding method as 33.48 L ha-1 and 6.6 L ha-1, respectively.

  12. Effects of Tillage and Mulch Methods on Soil Moisture in Wheat Fields of Loess Plateau,China

    Institute of Scientific and Technical Information of China (English)

    GAOZHIQIANG; YINJUN; 等

    1999-01-01

    Effects of different methods of tillage and mulch on soil moisture at fallow stage were studied in rainy and rain-deficient years.Soil moisture content per 20 cm was measured vertically within 0-300 cm soil layers in an experiment with five treatments:deep-loosening tillage(DLT),traditional tillage(TT),plastic mulch(PM),straw mulch(SM) and plastic plus straw mulch(PSM),All mulch treatments were under no tillage conditions.Total storage of precipitation in soil from 0 to 300cm was determined before sowing,Results showed that the new methods of tillage and mulch were the basic ways to improve water condition in dryland wheat fields.In a rainy year,PM with no tillage played a significant role in storing and conserving precipitation.while in a rain-deficient year,the role was not significant,Due to evaporation.DLT did not promote the storage of soil moisture,SM was the best way to store and conserve soil moisture,In SM treatment the wheat yields increased by more than 20%.

  13. Effects of Tillage Practices on Soil Penetration Resistance, Technical Parameters and Wheat Yield

    Directory of Open Access Journals (Sweden)

    S.M.j Afzali

    2013-02-01

    Full Text Available This study was carried out to evaluate the effects of tillage practices (with different depths on soil penetration resistance, technical parameters and grain yield of wheat crop. The experiment was conducted as a randomized complete block design with three replications for two years. Treatments included: moldboard plow fallowed by two passes of disc harrow and leveler (CT, two passes of disc harrow plus leveler (RT, subsoiler fallowed by two passes of disc harrow and leveler (S1D and subsoiler fallowed by rotivator (S1R. The results showed that soil compaction and penetration resistance increased at the end of growth stages because of irrigation operations and cohesion force of soil particles. However due to increasing of cumulative infiltration, it can be concluded that subsoiler caused the formation of micro cracks in different depths of soil. From technical indices viewpoint comparing to CT treatment, S1D and S1R treatments saved fuel consumption up to 2.2 and 10.44 lit ha 1 and tillage operation time up to 0.58 and 1.54 h ha-1, respectively. The result of grain yield assessment showed an increase of 8.5% in grain yield after replacing moldboard plow with annual subsoiling. Subsoiling has advantages such as, good technical indices, elimination of preplanting irrigation and fewer operations in planting time. Finally, subsoiling increased grain yield by 22% as compared to reduced tillage practice

  14. Effect of Traffic and Tillage on Agriculture Machine Traction and Fuel Consumption in Northern China Plain

    Directory of Open Access Journals (Sweden)

    Hao Chen

    2014-04-01

    Full Text Available Controlled traffic with conservation tillage can reduce soil compaction, thus to improve operation performance and fuel consumption of agricultural machine. Northern Chinese Plain is one of the main agricultural production bases with high level of agricultural mechanization. To explore the effect of wheel traffic on machine traction force and fuel consumption, three treatments were conducted: zero tillage with Controlled Traffic (NTCN, Compacted Treatment (CT and traditional tillage system with random traffic (CK. Results showed that wheel traffic increased soil bulk density in the top soil layer in both fully compacted and random compacted plots. Controlled traffic system should certain potential on soil compaction amelioration. Controlled traffic system reduced traction force on winter wheat planting by 9.5 and 6.3%, compared with fully compacted treatment and random compacted treatment. Controlled traffic system reduced fuel consumption in both winter wheat planting and sub soiling (significantly, compared with fully compacted treatment and random compacted treatment. Results indicated that controlled traffic system had certain advantages in soil compaction and fuel consumption in this region and with high application potential.

  15. Tillage and manure effects on soil and aggregate-associated carbon and nitrogen

    OpenAIRE

    Mikha, M.M.; C. W. Rice

    2004-01-01

    Metadata only record This study assesses the impacts of tillage methods (conventional(CT) versus no-tillage(NT)) and nitrogen source (fertilizer(F) versus manure(M)) on soil aggregate size and the associated soil carbon and nitrogen. They find that both no-tillage and manure increase soil aggregate size, with the combination of the two producing the greatest soil aggregation. Likewise, there was greater total carbon and nitrogen in the soil for the no-tillage and manure treatments.

  16. Effects of Reduced Tillage on Crop Yield, Plant Available Nutrients and Soil Organic Matter in a 12-Year Long-Term Trial under Organic Management

    Directory of Open Access Journals (Sweden)

    Wilhelm Claupein

    2013-09-01

    Full Text Available A field experiment was performed in Southwest Germany to examine the effects of long-term reduced tillage (2000–2012. Tillage treatments were deep moldboard plow: DP, 25 cm; double-layer plow; DLP, 15 + 10 cm, shallow moldboard plow: SP, 15 cm and chisel plow: CP, 15 cm, each of them with or without preceding stubble tillage. The mean yields of a typical eight-year crop rotation were 22% lower with CP compared to DP, and 3% lower with SP and DLP. Stubble tillage increased yields by 11% across all treatments. Soil nutrients were high with all tillage strategies and amounted for 34–57 mg kg−1 P and 48–113 mg kg−1 K (0–60 cm soil depth. Humus budgets showed a high carbon input via crops but this was not reflected in the actual Corg content of the soil. Corg decreased as soil depth increased from 13.7 g kg−1 (0–20 cm to 4.3 g kg−1 (40–60 cm across all treatments. After 12 years of experiment, SP and CP resulted in significantly higher Corg content in 0–20 cm soil depth, compared to DP and DLP. Stubble tillage had no significant effect on Corg. Stubble tillage combined with reduced primary tillage can sustain yield levels without compromising beneficial effects from reduced tillage on Corg and available nutrient content.

  17. [Effect of tillage patterns on the structure of weed communities in oat fields in the cold and arid region of North China].

    Science.gov (United States)

    Zhang, Li; Zhang, Li; Wu, Dong-Xia; Zhang, Jun-Jun

    2014-06-01

    In order to clarify the effects of tillage patterns on farmland weed community structure and crop production characteristics, based on 10 years location experiment with no-tillage, subsoiling and conventional tillage in the cold and arid region of North China, and supplementary experiment of plowing after 10 years no-tillage and subsoiling, oat was planted in 2 soils under different tillage patterns, and field weed total density, dominant weed types, weed diversity index, field weed biomass and oats yield were measured. The results showed that the regional weed community was dominated by foxtail weed (Setaira viridis); the weed density under long-term no-tillage was 2.20-5.14 times of tillage at different growing stages of oat, but there were no significant differences between conditional tillage and plowing after long-term no-tillage and subsoiling. Field weed Shannon diversity indices were 0.429 and 0.531, respectively, for sandy chestnut soil and loamy meadow soil under no-tillage conditions, and field weed biomass values were 1.35 and 2.26 times of plowing treatment, while the oat biomass values were only 2807.4 kg x hm(-2) and 4053.9 kg x hm(-2), decreased by 22.3% and 46.2%, respectively. The results showed that the weed community characteristics were affected by both tillage patterns and soil types. Long-term no-tillage farmland in the cold and arid region of North China could promote the natural evolution of plant communities by keeping more perennial weeds, and the plowing pattern lowered the annual weed density, eliminated perennial weeds with shallow roots, and stimulated perennial weeds with deep roots.

  18. [Effects of no-tillage on soil water content and physical properties of spring corn fields in semiarid region of northern China].

    Science.gov (United States)

    Yu, Hai-Ying; Peng, Wen-Ying; Ma, Xiu; Zhang, Ke-Li

    2011-01-01

    Field experiments were conducted in 2006-2008 to study the effects of no-tillage on the spatiotemporal dynamics of soil water content and related soil physical properties in spring corn fields in Beijing region during growth season. In study period, the water storage in 0-100 cm soil layer in tillage and no-tillage treatments had the same variation trend with time and precipitation, but the water storage at different time periods and under different precipitations was 2.7%-30.3% higher in no-tillage treatment than in tillage treatment. When the precipitation was relatively abundant, the increment of soil water storage was somewhat increased, but no-tillage was still worth to be popularized in the regions relatively deficit in precipitation. Under no-tillage, the average water storage in 0-100 cm soil layer during the three growth seasons in 2006-2008 was 3.4%-12.8% higher than that under conventional tillage, and the increment of the water storage in 0-20 cm and 80-100 cm soil layers under no-tillage was higher than that in intermediate layer, with the highest increment reached 22.2%. No-tillage improved soil water-holding capacity and water use efficiency via decreasing soil bulk density, increasing soil porosity, and promoting the formation of soil water-stable aggregates, and thereby, promoted crop yielding. After 3 years no-tillage, the soil water use efficiency and spring corn yield were increased by 13.3% and 16.4%, respectively, compared with those under conventional tillage.

  19. Chemical, green and organic manure effects on chemical properties on a savannah oxisol and on corn under conventional tillage and no-tillage

    Science.gov (United States)

    Mannigel, Anny R.; Alves, Marlene C.; Valério Filho, Walter V.

    2015-04-01

    Modern agriculture, in general, has always been based on the concept that natural resources are endless; however, this concept is changing. Concern for the environment is increasingly becoming part of farming practices, either by the awareness of society, or because the high cost of fertilizers or even the exhaustion of soils. The objective of this research was to evaluate the effects of the green manure and mineral fertilizer and/or organic manure and, on the chemical properties of an Oxisol, on "Savannah" (cerrado) area in Mato Grosso do Sul-Brazil, cultivated with corn (Zea mays L.) on the following management conditions: no-tillage and conventional tillage, on area previously under pasture (Brachiaria decumbens). The experimental design was a randomized blocks and the tested treatments were: control (without organic manure or chemical fertilizer); chemical fertilizer, as recommended for the culture and based on the chemical soil analysis; organic manure (cow manure); organic manure + half of the mineral fertilizer recommended rate; and the green manure Crotalaria juncea and Pennisetum americanum. The chemical analyses were the soil chemical analysis to the intent of soil fertility. Corn yield was evaluated. The collect of soil samples were realized in depths of 0.00-0.05 m and 0.05-0.10 m and 0.10-0.20 m. The organic manure and the organic manure + half of the mineral recommended rate increased P, Ca, Mg, K and Organic Matter in the first depth (0.00 - 0.05 m). These treatments also increased K and Mg at the second depth analyzed (0.05 - 0.10 m) and K in the depth from 0.10 - 0.20 m. Under conventional tillage management presents better crop results with an average grain yield of 3649 kg ha-1 versus 2374 kg ha-1 obtained under no-tillage. The use of chemical fertilizer, organic manure + half of the mineral recommended rate, Crotalaria juncea, organic manure and Pennisetum americanum increased corn yield by 84, 79, 58, 44 and 41 %, respectively.

  20. Temporary effect of chiseling on the compaction of a Rhodic Hapludox under no-tillage

    Directory of Open Access Journals (Sweden)

    Sâmala Glícia Carneiro Silva

    2012-04-01

    Full Text Available Mechanical chiseling has been used to alleviate the effects of compaction in soils under no-tillage (NT. However, its effect on the soil physical properties does not seem to have a defined duration period. The purpose of this study was to evaluate the behavior of the bulk density (BD and degree of compaction (DC at different soil depths, after chiseling in no-tillage, for one year. The experiment was performed in Ponta Grossa, Paraná State, Brazil, using an Oxisol (Rhodic Hapludox. Bulk density and DC were previously measured in an area under NT for 16 years, then immediately after chiseling (CHI in May 2009, six months after chiseling (CHI6M in October 2009 and one year after chiseling (CHI12M in May 2010. In the layers 0.0-0.10, 0.10-0.20 and 0.20-0.30 m, there was a significant BD reduction CHI and a marked increase CHI6M. The BD values measured CHI12M were similar to those before tillage. Chiseling reduced the DC in the layers 0.0-0.10 m and 0.10-0.20 m, but returned to the initial values one year later. During the evaluation periods CHI, CHI6M and CHI12M, the BD increased in the layer 0.30-0.40 m, compared with NT. The highest DC values were observed six months after chiseling; nevertheless the structural recovery of the soil was considerable, possibly due to the high degree of soil resilience and the influence of the wetting and drying cycles detected in the study period. The chiseling effects, evaluated by BD and DC, lasted less than one year, i.e., the beneficial short-term effects of chiseling on the reduction of the surface BD increased the risk of compaction in deeper soil layers.

  1. Tillage and residue management effect on soil properties, crop performance and energy relations in greengram (Vigna radiata L. under maize-based cropping systems

    Directory of Open Access Journals (Sweden)

    J.R. Meena

    2015-12-01

    Full Text Available Effect of tillage and crop residue management on soil properties, crop performance, energy relations and economics in greengram (Vigna radiata L. was evaluated under four maize-based cropping systems in an Inceptisol of Delhi, India. Soil bulk density, hydraulic conductivity and aggregation at 0–15 cm layer were significantly affected both by tillage and cropping systems, while zero tillage significantly increased the soil organic carbon content. Yields of greengram were significantly higher in maize–chickpea and maize–mustard systems, more so with residue addition. When no residue was added, conventional tillage required 20% higher energy inputs than the zero tillage, while the residue addition increased the energy output in both tillage practices. Maize–wheat–greengram cropping system involved the maximum energy requirement and the cost of production. However, the largest net return was obtained from the maize–chickpea–greengram system under the conventional tillage with residue incorporation. Although zero tillage resulted in better aggregation, C content and N availability in soil, and reduced the energy inputs, cultivation of summer greengram appeared to be profitable under conventional tillage system with residue incorporation.

  2. Nitrogen, tillage, and crop rotation effects on carbon dioxide and methane fluxes from irrigated cropping systems.

    Science.gov (United States)

    Alluvione, Francesco; Halvorson, Ardell D; Del Grosso, Stephen J

    2009-01-01

    Long-term effects of tillage intensity, N fertilization, and crop rotation on carbon dioxide (CO(2)) and methane (CH(4)) flux from semiarid irrigated soils are poorly understood. We evaluated effects of: (i) tillage intensity [no-till (NT) and conventional moldboard plow tillage (CT)] in a continuous corn rotation; (ii) N fertilization levels [0-246 kg N ha(-1) for corn (Zea mays L.); 0 and 56 kg N ha(-1) for dry bean (Phaseolus vulgaris L.); 0 and 112 kg N ha(-1) for barley (Hordeum distichon L.)]; and (iii) crop rotation under NT soil management [corn-barley (NT-CB); continuous corn (NT-CC); corn-dry bean (NT-CDb)] on CO(2) and CH(4) flux from a clay loam soil. Carbon dioxide and CH(4) fluxes were monitored one to three times per week using vented nonsteady state closed chambers. No-till reduced (14%) growing season (154 d) cumulative CO(2) emissions relative to CT (NT: 2.08 Mg CO(2)-C ha(-1); CT: 2.41 Mg CO(2)-C ha(-1)), while N fertilization had no effect. Significantly lower (18%) growing season CO(2) fluxes were found in NT-CDb than NT-CC and NT-CB (11.4, 13.2 and 13.9 kg CO(2)-C ha(-1)d(-1) respectively). Growing season CH(4) emissions were higher in NT (20.2 g CH(4) ha(-1)) than in CT (1.2 g CH(4) ha(-1)). Nitrogen fertilization and cropping rotation did not affect CH(4) flux. Implementation of NT for 7 yr with no N fertilization was not adequate for restoring the CH(4) oxidation capacity of this clay loam soil relative to CT plowed and fertilized soil.

  3. Comparison of effects of machine performance parameters and energy indices of soybean production in conservation and conventional tillage systems

    Directory of Open Access Journals (Sweden)

    A Sharifi

    2016-09-01

    Full Text Available Introduction Nowadays, agricultural systems are seeking economic, ecological and bioenvironmental goals for production of agricultural crops with protection and sustainability of the environment. Therefore, there is need to extend sustainable agricultural systems such as conservation agriculture. One of the principles of conservation agriculture is conservation tillage. Conservation tillage is a kind of tillage that retains crop residues on the soil surface or mixes it with soil using related machines. It could also affect on machine performance parameters. Energy consumption for producing one kilogram crop could be studied for conservation tillage. Several researchers have conducted studies on this issue for production of different crops including wheat, sunflower and forage crops. This study conducted to assess machine performance parameters and energy indices of conservation tillage systems for soybean cultivation in Golestan province. Materials and Methods This study was conducted to investigate the effects of conservation tillage systems on machine performance and energy indices in soybean production at the Gorgan research station of Golestan Agricultural and Natural Resource Research Center in 2012. The precipitation was 450 mm. Soil texture was silty clay loam. Treatments were four tillage methods, including no-till using row crop direct planter, no-till using grain direct drill, conventional tillage usin a disk harrow with working depth of 10-15 cm and minimum tillage using chisel packer with a working depth of 20 cm. Machine performance parameters and energy indices studied in a farm covered by wheat residues in a randomized complete block design (RCBD with four treatments and four replications. Machine performance parameters consisted of field efficiency, field capacity, total field capacity and planting uniformity index were measured. Energy indices such as energy ratio, energy productivity, energy intensity and net energy gain were

  4. Effects of 30 Years of Crop Rotation and Tillage on Bacterial and Archaeal Ammonia Oxidizers.

    Science.gov (United States)

    Munroe, Jake W; McCormick, Ian; Deen, William; Dunfield, Kari E

    2016-05-01

    Ammonia-oxidizing bacteria (AOB) and archaea (AOA) both mediate soil nitrification and may have specialized niches in the soil. Little is understood of how these microorganisms are affected by long-term crop rotation and tillage practices. In this study, we assessed abundance and gene expression of AOB and AOA under two contrasting crop rotations and tillage regimes at a 30-yr-old long-term experiment on a Canadian silt loam soil. Continuous corn ( L.) (CC) was compared with a corn-corn-soybean [ (L.) Merr.]-winter wheat ( L.) rotation under-seeded with red clover ( L.) (RC), with conventional tillage (CT) and no-till (NT) as subplot treatments. Soil sampling was performed during the first corn year at four time points throughout the 2010 season and at three discrete depths (0-5, 5-15, and 15-30 cm). Overall, AOA abundance was found to be more than 10 times that of AOB, although AOA transcriptional activity was below detectable levels across all treatments. Crop rotation had a marginally significant effect on AOB abundance, with 1.3 times as many gene copies under the simpler CC rotation than under the more diverse RC rotation. More pronounced effects of depth on AOB abundance and gene expression were observed under NT versus CT management, and NT supported higher abundances of total archaea and AOA than CT across the growing season. We suggest that AOB may be more functionally important than AOA in this high-input agricultural soil but that NT management can promote enhanced soil archaeal populations. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  5. Scenario Analysis of Tillage, Residue and Fertilization Management Effects on Soil Organic Carbon Dynamics

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-Bin; CAI Dian-Xiong; W.B.HOOGMOED; O.OENEMA; U.D.PERDOK

    2005-01-01

    Based on data from 10-year field experiments on residue/fertilizer management in the dryland farming region of northern China, Century model was used to simulate the site-specific ecosystem dynamics through adjustment of the model's parameters, and the applicability of the model to propose soil organic carbon (SOC) management temporally and spatially, in cases such as of tillage/residue/fertilization management options, was identified via scenario analysis.Results between simulations and actual measurements were in close agreement when appropriate applications of stover,manure and inorganic fertilizer were combined. Simulations of extreme C/N ratios with added organic materials tended to underestimate the measured effects. Scenarios of changed tillage methods, residue practices and fertilization options showed potential to maintain and enhance SOC in the long run, while increasing inorganic N slowed down the SOC turnover rate but did not create a net C sink without any organic C input. The Century model simulation showed a good relationship between annual C inputs to the soil and the rate of C sequestration in the top 20 cm layer and provided quantitative estimations of changes in parameters crucial for sustainable land use and management. Conservation tillage practices for sustainable land use should be integrated with residue management and appreciable organic and inorganic fertilizer application, adapted according to the local residue resource, soil fertility and production conditions. At least 50%residue return into the soil was needed annually for maintenance of SOC balance, and manure amendment was important for enhancement of SOC in small crop-livestock systems in which crop residue land application was limited.

  6. Long-term tillage effects on the distribution of P fractions of German loess soils

    Science.gov (United States)

    Piegholdt, C.; Geisseler, D.; Koch, H.-J.; Ludwig, B.

    2012-04-01

    Different tillage systems may affect P dynamics in soils due to differently distributed plant residues, different aggregate dynamics and erosion losses. Objectives were to investigate the effect of tillage on the availability of P in a long-term field trial initiated from 1990 to 1997. Four research sites located in eastern and southern Germany were established with a crop rotation consisting of two times winter wheat followed by sugar beet. The two treatments were no-till (NT), i.e. without cultivation, and conventional tillage (CT) down to 25-30 cm on loess soils. Soil P was divided into pools of different stabilities by a sequential extraction method and total P (Pt) was extracted by digesting the extracts of the fractionation to calculate organic P (Po). The Pt content (792 mg kg-1 soil) in the topsoil of the plots with NT was 15% higher than the content of Pt in the CT plots, while with increasing depth the Pt concentration decreased more under NT than under CT. This was also true for the other P fractions. The higher P contents in the topsoil of NT resulted presumably from the shallower incorporation of harvest residues compared to CT, whereas estimated soil losses and thus also P losses due to water erosion were only small for all four sites and treatments. Contents of oxalate extractable iron and organic carbon were positively related to the labile inorganic P (Pi) fractions, while there was a high correlation of the stable fractions with the clay contents and pH. Overall, the regression analyses indicated that labile P contents were controlled by the contents of organic C, while stable P contents depended on the contents of clay, oxalate-extractable Fe and Al, which suggested that the mineralization of organic matter provided available P. Overall, the tillage treatments had only little (and generally insignificant) effect on the total P content with a slightly increased soil P content under NT compared to CT mainly due to an increase in the content of

  7. Variable rainfall intensity and tillage effects on runoff, sediment, and carbon losses from a loamy sand under simulated rainfall.

    Science.gov (United States)

    Truman, C C; Strickland, T C; Potter, T L; Franklin, D H; Bosch, D D; Bednarz, C W

    2007-01-01

    The low-carbon, intensively cropped Coastal Plain soils of Georgia are susceptible to runoff, soil loss, and drought. Reduced tillage systems offer the best management tool for sustained row crop production. Understanding runoff, sediment, and chemical losses from conventional and reduced tillage systems is expected to improve if the effect of a variable rainfall intensity storm was quantified. Our objective was to quantify and compare effects of a constant (Ic) intensity pattern and a more realistic, observed, variable (Iv) rainfall intensity pattern on runoff (R), sediment (E), and carbon losses (C) from a Tifton loamy sand cropped to conventional-till (CT) and strip-till (ST) cotton (Gossypium hirsutum L.). Four treatments were evaluated: CT-Ic, CT-Iv, ST-Ic, and ST-Iv, each replicated three times. Field plots (n=12), each 2 by 3 m, were established on each treatment. Each 6-m2 field plot received simulated rainfall at a constant (57 mm h(-1)) or variable rainfall intensity pattern for 70 min (12-run ave.=1402 mL; CV=3%). The Iv pattern represented the most frequent occurring intensity pattern for spring storms in the region. Compared with CT, ST decreased R by 2.5-fold, E by 3.5-fold, and C by 7-fold. Maximum runoff values for Iv events were 1.6-fold higher than those for Ic events and occurred 38 min earlier. Values for Etot and Ctot for Iv events were 19-36% and 1.5-fold higher than corresponding values for Ic events. Values for Emax and Cmax for Iv events were 3-fold and 4-fold higher than corresponding values for Ic events. Carbon enrichment ratios (CER) were or=1.0 for CT plots (except for first 20 min). Maximum CER for CT-Ic, CT-Iv, ST-Ic, and ST-Iv were 2.0, 2.2, 1.0, and 1.2, respectively. Transport of sediment, carbon, and agrichemicals would be better understood if variable rainfall intensity patterns derived from natural rainfall were used in rainfall simulations to evaluate their fate and transport from CT and ST systems.

  8. Winter effect on soil microorganisms under different tillage and phosphorus management practices in eastern Canada.

    Science.gov (United States)

    Shi, Yichao; Lalande, Roger; Hamel, Chantal; Ziadi, Noura

    2015-05-01

    Determining how soil microorganisms respond to crop management systems during winter could further our understanding of soil phosphorus (P) transformations. This study assessed the effects of tillage (moldboard plowing or no-till) and P fertilization (0, 17.5, or 35 kg P·ha(-1)) on soil microbial biomass, enzymatic activity, and microbial community structure in winter, in a long-term (18 years) corn (Zea mays L.) and soybean (Glycine max L.) rotation established in 1992 in the province of Quebec, Canada. Soil samples were collected at 2 depths (0-10 and 10-20 cm) in February 2010 and 2011 after the soybean and the corn growing seasons, respectively. Winter conditions increased the amounts of soil microbial biomasses but reduced the overall enzymatic activity of the soil, as compared with fall levels after corn. P fertilization had a quadratic effect on the amounts of total, bacterial, arbuscular mycorrhizal fungi phospholipid fatty acid markers after corn but not after soybean. The soil microbial community following the soybean and the corn crops in winter had a different structure. These findings suggest that winter conditions and crop-year could be important factors affecting the characteristics of the soil microbial community under different tillage and mineral P fertilization.

  9. [Effects of Short-time Conservation Tillage Managements on Greenhouse Gases Emissions from Soybean-Winter Wheat Rotation System].

    Science.gov (United States)

    Xie, Yan; Chen, Xi; Hu, Zheng-hua; Chen, Shu-tao; Zhang, Han; Ling, Hui; Shen, Shuang-he

    2016-04-15

    Field experiments including one soybean growing season and one winter-wheat growing season were adopted. The experimental field was divided into four equal-area sub-blocks which differed from each other only in tillage managements, which were conventional tillage (T) , no-tillage with no straw cover ( NT) , conventional tillage with straw cover (TS) , and no-tillage with straw cover (NTS). CO₂ and N₂O emission fluxes from soil-crop system were measured by static chamber-gas chromatograph technique. The results showed that: compared with T, in the soybean growing season, NTS significantly increased the cumulative amount of CO₂ (CAC) from soil-soybean system by 27.9% (P = 0.045) during the flowering-podding stage, while NT significantly declined CAC by 28.9% (P = 0.043) during the grain filling-maturity stage. Compared with T, NT significantly declined the cumulative amount of N₂O (CAN) by 28.3% (P = 0.042) during the grain filling-maturity stage. In the winter-wheat growing season, compared with T, TS and NT significantly declined CAC by 24.3% (P = 0.032) and 36.0% (P = 0.041) during the elongation-booting stage, and also declined CAC by 26.8% (P = 0.027) and 33.1% (P = 0.038) during the maturity stage. During the turning-green stage, compared with T treatment, NT, NTS, and TS treatments had no significant effect on CAN, while NTS significant declined CAN by 42.0% (P = 0.035) compared with NT. Our findings suggested that conservation tillage managements had a more significant impact on CO₂ emission than 20 emission from soil-crop system.

  10. Effect of tillage practices on least limiting water range in Northwest India

    Science.gov (United States)

    Kahlon, Meharban S.; Chawla, Karitika

    2017-04-01

    Tillage practices affect mechanical and hydrological characteristics of soil and subsequently the least limiting water range. This quality indicator under the wheat-maize system of northwest India has not been studied yet. The treatments included four tillage modes, namely conventional tillage, no-tillage without residue, no-tillage with residue, and deep tillage as well as three irrigation regimes based on the irrigation water and pan evaporation ratio i.e. 1.2, 0.9, and 0.6. The experiment was conducted in a split plot design with three replications. At the end of cropping system, the mean least limiting water range (m3 m-3) was found to be highest in deep tillage (0.26) and lowest in notillage without residue (0.15). The field capacity was a limiting factor for the upper range of the least limiting water range beyond soil bulk density 1.41 Mg m-3 and after that 10% air filled porosity played a major role. However, for the lower range, the permanent wilting point was a critical factor beyond soil bulk density 1.50 Mg m-3 and thereafter, the penetration resistance at 2 MPa becomes a limiting factor. Thus, deep tillage under compaction and no-tillage with residue under water stress is appropriate practice for achieving maximum crop and water productivity.

  11. Effects of No-tillage Combined with Reused Plastic Film Mulching on Maize Yield and Irrigation Water Productivity

    Directory of Open Access Journals (Sweden)

    SU Yong-zhong

    2016-09-01

    Full Text Available A field experiment was conducted to determine the effects of reused plastic film mulching and no-tillage on maize yield and irriga-tion water productivity(IWP in the marginal oasis in the middle of Hexi Corridor region of northwestern China. The aim is to provide an alternative tillage and cultivation pattern for reducing plastic film pollution, saving cost and increasing income, and improving resource use efficiency. The field experiment was carried out in three soils with different textures and fertility levels. Three treatments for each soil were set up:(1 conventional tillage,winter irrigation, and new plastic mulching cultivation(NM;(2 no tillage, less winter irrigation and reused plastic mulching cultivation (RM;(3 no tillage, less winter irrigation and reused plastic mulching combined with straw mulching (RMS. The results showed that the average daily soil temperature in the two reused plastic mulching treatment(RM and RMS during maize sowing and elongation stage was lower 0.6~1.0℃(5 cm depth and 0.5~0.8℃(15 cm depth than that in the NM. This result suggested that no tillage and reused plastic mulching cultivation still had the effect of increasing soil temperature. Maize grain yield in the RM was reduced by 4.4%~10.6% compared with the conventional cultivation(NM, while the net income increased due to saving in plastic film and tillage ex-penses. There was no significant difference in maize grain yield between the RMS and NM treatment, but the net income in the RMS was in-creased by 12.5%~17.1% than that in the NM. Compared with the NM, the two reused plastic film mulching treatments (RM and RMS decreased the volume of winter irrigation, but maize IWP increased. Soil texture and fertility level affected significantly maize nitrogen uptake and IWP. In the arid oases with the shortage of water resources, cultivation practices of conservation tillage with recycle of plastic film is an ideal option for saving cost and increasing income

  12. Effects of Different Tillage Methods on Soil Microbial Quantity%不同耕作方式对土壤微生物数量的影响

    Institute of Scientific and Technical Information of China (English)

    李桂喜; 董存元; 陈希元; 岳燕军

    2012-01-01

    为了研究冀北坝上半干旱区不同耕作方式对土壤微生物数量的影响,以小麦和燕麦为例,试验共设免耕、传统、年年深松、年年浅松、浅旋和隔年深松6个不同耕作方式处理,研究土壤微生物数量与不同耕作方式之间的关系.结果表明,土壤微生物数量在不同耕作方式下随着土层深度的增加而明显降低;与传统耕作方式相比,保护性耕作模式均可提升细菌、真菌、放线茵数量.%The effect of different tillage modes on soil microbial quantity in semiarid area of Bashang in North Hebei was studied using wheat and oats as material. 6 treatments including no-tillage, traditional, continuously subsoiling, continuously surface tillage, surface rotary and surface tillage every two years were conducted to study the relationship between soil microbial biomass and tillage modes. The results showed that quantity of soil microbial decreased obviously with the increase of soil depth in different tillage modes. Compared with conventional tillage, conservation tillage could improve the quantity of soil bacteria, fungus, actinomyces.

  13. Tillage and fertility management effects on soil organic matter and sorghum yield in semi-arid West Africa

    NARCIS (Netherlands)

    Ouédraogo, E.; Mando, A.; Brussaard, L.; Stroosnijder, L.

    2007-01-01

    Whether it is traditional, modern or "sustainable" agriculture, soil organic matter plays a key role in sustaining crop production and in preventing land degradation. A field experiment was conducted on a Ferric Lixisol at Gampela (Burkina Faso) in 2000 and 2001 to carried out the effects of tillage

  14. Effect of rainfall timing and tillage on the transport of steroid hormones in runoff from manure amended row crop fields

    Science.gov (United States)

    Manure generated from concentrated animal feeding operations (CAFOs) represents one of the major sources of steroid hormones found in surface water. This paper presents results of a study conducted near Concord, NE to determine the effects of manure handling (compost vs. stockpile), tillage (no-till...

  15. Vegetation barrier and tillage effects on runoff and sediment in an alley crop system on a Luvisol in Burkina Faso

    NARCIS (Netherlands)

    Spaan, W.P.; Sikking, A.F.S.; Hoogmoed, W.B.

    2005-01-01

    The effects of vegetation barriers and tillage on runoff and soil loss were evaluated in an alley crop system at a research station in central Burkina Faso. On a 2% slope of a sandy loam various local species (grasses, woody species and a succulent) were planted as conservation barriers in order to

  16. Effects of tropical ecosystem engineers on soil quality and crop performance under different tillage and residue management

    Science.gov (United States)

    Pulleman, Mirjam; Paul, Birthe; Fredrick, Ayuke; Hoogmoed, Marianne; Hurisso, Tunsisa; Ndabamenye, Telesphore; Saidou, Koala; Terano, Yusuke; Six, Johan; Vanlauwe, Bernard

    2014-05-01

    Feeding a future global population of 9 billion will require a 70-100% increase in food production, resulting in unprecedented challenges for agriculture and natural resources, especially in Sub-saharan Africa (SSA). Agricultural practices that contribute to sustainable intensification build on beneficial biological interactions and ecosystem services. Termites are the dominant soil ecosystem engineers in arid to sub-humid tropical agro-ecosystems. Various studies have demonstrated the potential benefits of termites for rehabilitation of degraded and crusted soils and plant growth in semi-arid and arid natural ecosystems. However, the contribution of termites to agricultural productivity has hardly been experimentally investigated, and their role in Conservation Agriculture (CA) systems remains especially unclear. Therefore, this study aimed to quantify the effects of termites and ants on soil physical quality and crop productivity under different tillage and residue management systems in the medium term. A randomized block trial was set up in sub-humid Western Kenya in 2003. Treatments included a factorial combination of residue retention and removal (+R/-R) and conventional and reduced tillage (+T/-T) under a maize (Zea mays L.) and soybean (Glyxine max. L.) rotation. A macrofauna exclusion experiment was superimposed in 2005 as a split-plot factor (exclusion +ins; inclusion -ins) by regular applications of pesticides (Dursban and Endosulfan) in half of the plots. Macrofauna abundance and diversity, soil aggregate fractions, soil carbon contents and crop yields were measured between 2005 and 2012 at 0-15 cm and 15-30 cm soil depths. Termites were the most important macrofauna species, constituting between 48-63% of all soil biota, while ants were 13-34%, whereas earthworms were present in very low numbers. Insecticide application was effective in reducing termites (85-56% exclusion efficacy) and earthworms (87%), and less so ants (49-81%) at 0-15 cm soil depth

  17. Emissions of nitrous oxide from Irish arable soils: effects of tillage and reduced N input

    DEFF Research Database (Denmark)

    Abdalla, M.; Jones, M.B.; Ambus, Per

    2010-01-01

    Nitrous oxide (N2O) flux measurements from an Irish spring barley field managed under conventional and reduced tillage and different N fertilizer applications at the Teagasc Oak Park Research Centre were made for two consecutive seasons. The aim was to investigate the efficacy of reduced tillage ...

  18. Shallow tillage effects on soil properties for temperate-region hard-setting soils

    DEFF Research Database (Denmark)

    Schjønning, Per; Thomsen, Ingrid Kaag

    2013-01-01

    Shallow tillage (ST; typically ... above (‘ST-upper’) and below (‘ST-lower’) ST primary tillage depth. Soil organic carbon (SOC), water content, bulk density, air-filled pore space (ɛa) and air permeability (ka) at the field-sampled water content were determined. ST increased SOC concentration in the ST-upper soil when compared to MP...

  19. Long-term rotation and tillage effects on soil structure and crop yield

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Heck, R; Deen, B

    2013-01-01

    –C–S–S) corn, corn, soybean (Glycine max L.), soybean. A red clover (Trifolium pretense L.) cover crop was under seeded in oats and spring barley in R6. In 2010, first year corn was grown in R6 and R8. The tillage treatments included no tillage, NT and mouldboard ploughing, MP. Topsoil structural quality...

  20. Pesticide Interactions with N source and Tillage: Effects on soil biota and ecosystem services

    DEFF Research Database (Denmark)

    Jensen, John; Petersen, Søren O; Elsgaard, Lars

    . This study was planned to evaluate interactions between pesticide use and other soil management factors. The study was carried out within a long-term tillage experiment using two tillage practices (no-till (NT) and mouldboard ploughing (MP), two contrasting N sources (manure and mineral fertiliser), and two...

  1. Effects of strip and full-width tillage on soil carbon IV oxide-carbon ...

    African Journals Online (AJOL)

    Yomi

    Highest CO2-C fluxes, bacteria ... Key words: Carbon IV oxide-carbon flux, soil bacteria and fungi, strip tillage, full-width tillage, sunflower. .... Urea fertilizer (50 kg N ha-1) and triple ..... mulch on soil physical properties and growth of maize.

  2. Elevated atmospheric carbon dioxide effects on soybean and sorghum gas exchange in conventional and no-tillage systems.

    Science.gov (United States)

    Prior, S A; Runion, G B; Rogers, H H; Arriaga, F J

    2010-01-01

    Increasing atmospheric CO(2) concentration has led to concerns about potential effects on production agriculture. In the fall of 1997, a study was initiated to compare the response of two crop management systems (conventional tillage and no-tillage) to elevated CO(2). The study used a split-plot design replicated three times with two management systems as main plots and two atmospheric CO(2) levels (ambient and twice ambient) as split plots using open-top chambers on a Decatur silt loam soil (clayey, kaolinitic, thermic Rhodic Paleudults). The conventional system was a grain sorghum [Sorghum bicolor (L.) Moench.] and soybean [Glycine max (L.) Merr.] rotation with winter fallow and spring tillage practices. In the no-tillage system, sorghum and soybean were rotated, and three cover crops were used [crimson clover (Trifolium incarnatum L.), sunn hemp (Crotalaria juncea L.), and wheat (Triticum aestivum L.)]. Over multiple growing seasons, the effect of management and CO(2) concentration on leaf-level gas exchange during row crop (soybean in 1999, 2001, and 2003; sorghum in 2000, 2002, and 2004) reproductive growth were evaluated. Treatment effects were fairly consistent across years. In general, higher photosynthetic rates were observed under CO(2) enrichment (more so with soybean) regardless of residue management practice. Elevated CO(2) led to decreases in stomatal conductance and transpiration, which resulted in increased water use efficiency. The effects of management system on gas exchange measurements were infrequently significant, as were interactions of CO(2) and management. These results suggest that better soil moisture conservation and high rates of photosynthesis can occur in both tillage systems in CO(2)-enriched environments during reproductive growth.

  3. [Effects of tillage at pre-planting of winter wheat and summer maize on leaf senescence of summer maize].

    Science.gov (United States)

    Li, Xia; Zhang, Ji-wang; Ren, Bai-zhao; Fan, Xia; Dong, Shu-ting; Liu, Peng; Zhao, Bin

    2015-05-01

    This study explored the effects of different tillage treatments at pre-planting winter wheat and summer maize on leaf senescence physiological characteristics of summer maize in double cropping system. Zhengdan 958 was used as experimental material. Three tillage treatments, including rotary tillage before winter wheat seeding and no-tillage before summer maize seeding (RN), mold- board plow before winter wheat seeding and no-tillage before summer maize seeding (MN), and moldboard plow before winter wheat seeding and rotary tillage before summer maize seeding (MR), were designed to determine the effects of different tillage treatments on leaf area (LA) , leaf area reduction, photosynthetic pigments content, superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activities and malondialdehyde (MDA) content in ear leaves of summer maize after tasselling (VT). LA of MN and MR were higher than that of RN from VT to 40 days after tasseling (VT + 40) and LA reduction of MR was the highest after VT + 40. As for MR, MN and NT, the photosynthetic pigments content got the maximum value at 20 days after tasselling (VT + 20) and then decreased, following the change of unimodal curve. At VT + 20, the contents of chlorophyll a in MR and MN were increased by 11.4% and 9.7%, the contents of chlorophyll b in MR and MN were increased by 14.9% and 15.9%, compared with RN. The soluble protein content in ear leaves decreased following the growth process in all treatments, and that of MR and MN remained 11.5% and 24.4% higher than that of RN from VT to VT + 40. SOD, CAT and POD activities of three treatments got the maximum values at VT + 20 and then decreased, following the change of unimodal curve. MDA content increased following the growth process in all treatments and that of RN always remained at high levels. Grain yields of MN and MR were 24.0% and 30.6% greater than that of RN, respectively. Grain yield of MR was 5.2% higher than that of MN. In conclusion, the ability of

  4. 坡耕地不同保护性耕作措施对土壤酶活性的影响%Effect of different conservational tillage of sloping land on the activity of soil enzyme

    Institute of Scientific and Technical Information of China (English)

    郑秋颖; 周连仁; 赵红

    2012-01-01

    以黑龙江省海伦市坡耕地长期保护性耕作为研究对象,探讨5种耕作方式:免耕、少耕、横坡垄、垄向区田(前4种视为保护性耕作)及常规翻耕对土壤过氧化氢酶活性、脲酶活性及蔗糖酶活性的影响.结果表明,免耕、少耕、横坡垄及垄向区田的过氧化氢酶活性高于常规翻耕1.70%~34.21%;免耕和少耕处理的脲酶活性及蔗糖酶活性高于其他耕作处理4.81%~67.94%;横坡垄和垄向区田处理的脲酶活性及蔗糖酶活性高于常规翻耕8.97%~36.00%;过氧化氢酶、脲酶及蔗糖酶活性均于大豆鼓粒期显示活性最高值.免耕和少耕相对于防治水土流失的横坡垄和垄向区田更能有效地培育黑土,是适于坡耕地的耕作方式.%Based on the long-term conservational tillage experiment of sloping land of Heilongjiang Hailun City, the effect of five tillage treatments: no tillage, minimum tillage, cross ridge, ridge tillage (see as conservational tillage in former) and conventional plowing tillage on the activity of catalase, urease and sucrose were studied. Results showed that activity of catalase of no tillage, minimum tillage, cross ridge and ridge tillage was higher 1.70%-34.21% than that of plowing tillage; activity of urease and sucrose of no tillage and minimum tillage was higher 4.81%-67.94% than that of other tillage treatments; activity of urease and sucrose of cross ridge and ridge tillage was higher 8.97%-36.00% than that of plowing tillage; the highest activity of catalase, urease and sucrose was shown in podding period. No tillage and minimum tillage had more ability to fertilize black soil than cross ridge and ridge tillage, which could protect soil and water, thereby, no tillage and minimum tillage were fit for sloping land.

  5. Effects of Tillage Practices on Growth and Yield of Cassava (Manihot esculenta Crantz and some Soil Properties in Ibadan, Southwestern Nigeria

    Directory of Open Access Journals (Sweden)

    Ndaeyo, NU.

    2002-01-01

    Full Text Available Maintenance of soil fertility status and optimum crop yield has been a great task in Nigeria. Against this background, studies were conducted in 1994 and 1995 growing seasons at the Teaching and Research Farm, University of Ibadan, Nigeria to evaluate the productivity of cassava and soil properties and dynamics under some tillage practices. Randomized block design with four replications was used and the tillage treatments were Heaping [HP], No-Till + Herbicide [NTH], Ridging [RG] and No-Till-Slash and Burn [NSB]. Results revealed that tillage practices had no significant effect on sprouting percentage in 1994 but in 1995, HP treatment was significantly (P < 0.05 higher than others. Tillage had no marked effect on cassava height in both years while number of leaves only differed significantly (P < 0.05 8 months after planting with HP treatment being higher than others. Stem girth showed no marked differences among treatments in both years. Similarly, in both years, cassava fresh root yield and yield components were not significantly affected by tillage practices. NSB showed significantly higher soil bulk density at planting in both years than other treatments. Generally, soil chemical properties were not markedly affected by the tillage practices. The highest cost of production was observed under NSB while RG produced the highest returns. The study suggests that successful growing of cassava under reduced tillage practices is practicable in an Alfisol in this agro-ecological zone.

  6. Tillage and crop residue management methods had minor effects on the stock and stabilization of topsoil carbon in a 30-year field experiment.

    Science.gov (United States)

    Singh, Pooja; Heikkinen, Jaakko; Ketoja, Elise; Nuutinen, Visa; Palojärvi, Ansa; Sheehy, Jatta; Esala, Martti; Mitra, Sudip; Alakukku, Laura; Regina, Kristiina

    2015-06-15

    We studied the effects of tillage and straw management on soil aggregation and soil carbon sequestration in a 30-year split-plot experiment on clay soil in southern Finland. The experimental plots were under conventional or reduced tillage with straw retained, removed or burnt. Wet sieving was done to study organic carbon and soil composition divided in four fractions: 1) large macroaggregates, 2) small macroaggregates, 3) microaggregates and 4) silt and clay. To further estimate the stability of carbon in the soil, coarse particulate organic matter, microaggregates and silt and clay were isolated from the macroaggregates. Total carbon stock in the topsoil (equivalent to 200 kg m(-2)) was slightly lower under reduced tillage (5.0 kg m(-2)) than under conventional tillage (5.2 kg m(-2)). Reduced tillage changed the soil composition by increasing the percentage of macroaggregates and decreasing the percentage of microaggregates. There was no evidence of differences in the composition of the macroaggregates or carbon content in the macroaggregate-occluded fractions. However, due to the higher total amount of macroaggregates in the soil, more carbon was bound to the macroaggregate-occluded microaggregates in reduced tillage. Compared with plowed soil, the density of deep burrowing earthworms (Lumbricus terrestris) was considerably higher under reduced tillage and positively associated with the percentage of large macroaggregates. The total amount of microbial biomass carbon did not differ between the treatments. Straw management did not have discernible effects either on soil aggregation or soil carbon stock. We conclude that although reduced tillage can improve clay soil structure, generally the chances to increase topsoil carbon sequestration by reduced tillage or straw management practices appear limited in cereal monoculture systems of the boreal region. This may be related to the already high C content of soils, the precipitation level favoring decomposition and

  7. Effect of different fertilizer resources on yield and yield components of grain maize (Zea mays L. affected by tillage managements

    Directory of Open Access Journals (Sweden)

    Ahmad Ghasemi

    2016-03-01

    Full Text Available Introduction Due to the development of sustainable agriculture and the reduction of utilizing chemical fertilizers, it is essential to use organic fertilizer. Organic matter is vital to soil fertility and its productivity. To maintain the level of fertility and the strength of soil, organic matter levels should be maintained at an appropriate level. Unfortunately, the level of organic matter in soil is generally less than 1%. One solution to increase the soil’s organic matter content is to use organic fertilizers such as animal manure, green manure, and vermicompost (Nuralvandy, 2011. As a correction factor, green manure can increase water supply and nutrient soil conservation (Tajbakhsh et al., 2005. Materials and methods In order to assess the effects of fertilizer sources (green manure, cow manure, and chemical fertilizer on maize yield and yield components (KSC 704 under tillage management, a field experiment was carried out at Zahak Agricultural and Natural Resource Research Station in two years (from 2013 to 2014. Before corn planting, barley was planted as green manure in the fall of each year. The experiment was conducted as a split plot arranged in a completely randomized block design with three replications. The main plots were tillage and no tillage, whereas the sub plots were: 1-barley green manure (without application of fertilizer, 2-barley green manure with applying 100% chemical fertilizer (NPK to the barley during cultivation, tillering and stemming stages, 3- green manure with 2/3 of chemical fertilizer to the barley and 1/3 to the maize, 4- green manure with 1/3 of chemical fertilizer to the barley and 2/3 to the maize, 5- barley green manure with 50% animal and chemical manures, 6- barley green manure with 40 t ha-1 of animal manure, 7-control (non-fertilizer application. Corn was planted on 15 March each year. Phosphorus, potassium fertilizer, and animal manure were added to the soil as the base fertilizers. At full

  8. [Effects of no-tillage and fertilization on paddy soil CH4 and N2O emissions and their greenhouse effect in central China].

    Science.gov (United States)

    Dai, Guang-zhao; Li, Cheng-fang; Cao, Cou-gui; Zhan, Ming; Tong, Le-ga; Mei, Shao-hua; Zhai, Zhong-bing; Fan, Duan-yang

    2009-09-01

    By using static chamber-gas chromatographic techniques, the CH4 and N2O emissions from the paddy soil in southeast Hubei were measured. Four treatments were installed, i.e., no-tillage plus no-fertilization (NT0), conventional tillage plus no-fertilization (CT0), no-tillage plus fertilization (NTC), and conventional tillage plus fertilization (CTC). In all treatments, the CH4 emission had a seasonal variation of increasing first and decreasing then, while the N2O emission had no significant seasonal variation. Fertilization increased the CH4 and N2O emissions significantly. NT0 increased the CH4 emission and decreased the N2O emission significantly, compared with CT0; NTC only decreased the CH4 emission and increased the N2O emission slightly, compared with CTC. The analysis on the integrated greenhouse effect of CH4 and N2O showed that NT0 increased the effect by 25.9%, compared with CT0, while NTC decreased the effect by 10.1%, compared with CTC. Therefore, a reasonable arrangement of fertilization and no-tillage could reduce the integrated greenhouse effect of CH4 and N2O from paddy field.

  9. Evaluation of Tillage, Residue Management and Nitrogen Fertilizer Effects on CO2 Emission in Maize (Zea Mays L. Cultivation

    Directory of Open Access Journals (Sweden)

    Rooholla Moradi

    2016-02-01

    Full Text Available Introduction: The latest report of the Intergovernmental Panel on Climate Change (IPCC states that future emissions of greenhouse gases (GHGs will continue to increase and cause climatic change (16. These conditions are also true for Iran. The three greenhouse gases associated with agriculture are carbon dioxide (CO2, methane (CH4, and nitrous oxide (N2O. The three GHGs associated with agriculture CO2, CH4, and N2O differ in their effectiveness in trapping heat and in their turnover rates in the atmosphere. This environmental change will have serious impacts on different growth and development processes of crops. Increasing temperature could affect physiological processes such as photosynthesis, respiration and partitioning of photoassimilates. Farmers are not able to change or manage the climatic conditions, but some factors such as soil, water, seed and agricultural practices can be managed to reduce the adverse impacts of climate change (32. Mitigation and adaptation are two known ways for reducing the negative impacts of climate change. Mitigation strategies are associated with decreasing greenhouse gas (GHG emissions through management practices such as reducing chemical fertilizer application, mechanization, increasing carbon storage in agroecosystems, planting biofuel crops and moving towards organic farming (42, etc. Material and Methods: This study was carried out at the experimental field of the Ferdowsi University of Mashhad in 2011 and was repeated in 2012. The Research Station (36°16´N, 59°36´E is located at about 985 m a.s.l. Average temperature and precipitation rate of the research station in two years are shown in Figure. 1. The three-factor experiment was set up in a strip-split-plot arranged in a randomized complete block design with three replications. The experimental treatments were tillage systems (conventional and reduced tillage and residual management (remaining and leaving of maize residual assigned to main plots

  10. Effects of Long-term Conservation Tillage on Soil Nutrients in Sloping Fields in Regions Characterized by Water and Wind Erosion.

    Science.gov (United States)

    Tan, Chunjian; Cao, Xue; Yuan, Shuai; Wang, Weiyu; Feng, Yongzhong; Qiao, Bo

    2015-12-01

    Conservation tillage is commonly used in regions affected by water and wind erosion. To understand the effects of conservation tillage on soil nutrients and yield, a long-term experiment was set up in a region affected by water and wind erosion on the Loess Plateau. The treatments used were traditional tillage (CK), no tillage (NT), straw mulching (SM), plastic-film mulching (PM), ridging and plastic-film mulching (RPM) and intercropping (In). Our results demonstrate that the available nutrients in soils subjected to non-traditional tillage treatments decreased during the first several years and then remained stable over the last several years of the experiment. The soil organic matter and total nitrogen content increased gradually over 6 years in all treatments except CK. The nutrient content of soils subjected to conservative tillage methods, such as NT and SM, were significantly higher than those in soils under the CK treatment. Straw mulching and film mulching effectively reduced an observed decrease in soybean yield. Over the final 6 years of the experiment, soybean yields followed the trend RPM > PM > SM > NT > CK > In. This trend has implications for controlling soil erosion and preventing non-point source pollution in sloping fields by sacrificing some food production.

  11. Effect of Tillage in Day or Night and Application of Reduced Dosage of Imazethapyr and Trifluralin on Weed Control, Yield and Yield Components of Chickpea

    Directory of Open Access Journals (Sweden)

    A Abbasian

    2015-07-01

    Full Text Available This Experiment was arranged as a strip-plot on the base of a completely randomized block design with three replications to study the effect of tillage (whether in day or night or in day by light-proof cover and application of reduced dosage of imazethapyr and trifluralin on weed control, yield and yield components of chickpea. Main plots consisted of tillage methods and subplots consisted of trifluralin (at doses of 480, 960 and 1440 g ai /ha and imazethapyr (at doses of 50, 100 and 150 g ai /ha, plus weed free and weedy checks. Results showed weed biomass in day tillage, night tillage and in light-proof cover tillage were respectively 86, 127 and 148 g m-2. Therefore tillage at night or by light-proof cover in day time showed not enough efficiency in weed control. Weed biomass increased when application dose of herbicides decreased. Chickpea grain yield showed significant differences when different doses of herbicides applied. The minimum and the maximum seed yield were obtained respectively in weed free (by 208 g m-2 and weedy checks (by 123 g m-2. Reduced dosage of imazethapyr and trifluralin could control weeds good enough by no significant decrease in chickpea yield. Efficacy of imazethapyr to control weeds grown in chickpea was significantly better than that of trifluralin

  12. [Effects of different tillage and fertilization modes on the soil physical and chemical properties and crop yield under winter wheat/spring corn rotation on dryland of east Gansu, Northwest China].

    Science.gov (United States)

    Zhang, Jian-jun; Wang, Yong; Fan, Ting-lu; Guo, Tian-wen; Zhao, Gang; Dang, Yi; Wang, Lei; Li, Shang-zhong

    2013-04-01

    Based on the 7-year field experiment on the dryland of east Gansu of Northwest China in 2005-2011, this paper analyzed the variations of soil moisture content, bulk density, and nutrients content at harvest time of winter wheat and of the grain yield under no-tillage and conventional tillage and five fertilization modes, and approached the effects of different tillage and fertilization modes on the soil water storage and conservation, soil fertility, and grain yield under winter wheat/ spring corn rotation. In 2011, the soil moisture content in 0-200 cm layer and the soil bulk density and soil organic matter and available nitrogen and phosphorus contents in 0-20 cm and 20-40 cm layers under different fertilization modes were higher under no-tillage than under conventional tillage. Under the same tillage modes, the contents of soil organic matter and available nitrogen and available phosphorus were higher under the combined application of organic and inorganic fertilizers, as compared with other fertilization modes. The soil available potassium content under different tillage and fertilization modes decreased with years. The grain yield under conventional tillage was higher than that under no-tillage. Under the same tillage modes, the grain yield was the highest under the combined application of organic and inorganic fertilizers, and the lowest under no fertilization. In sum, no-tillage had the superiority than conventional tillage in improving the soil water storage and conservation and soil fertility, and the combined application of organic and inorganic fertilizers under conventional tillage could obtain the best grain yield.

  13. Effects of 24 Years of Conservation Tillage Systems on Soil Organic Carbon and Soil Productivity

    Directory of Open Access Journals (Sweden)

    Kenneth R. Olson

    2013-01-01

    Full Text Available The 24-year study was conducted in southern Illinois (USA on land similar to that being removed from Conservation Reserve Program (CRP to evaluate the effects of conservation tillage systems on: (1 amount and rates of soil organic carbon (SOC storage and retention, (2 the long-term corn and soybean yields, and (3 maintenance and restoration of soil productivity of previously eroded soils. The no-till (NT plots did store and retain 7.8 Mg C ha−1 more and chisel plow (CP −1.6 Mg C ha−1 less SOC in the soil than moldboard plow (MP during the 24 years. However, no SOC sequestration occurred in the sloping and eroding NT, CP, and MP plots since the SOC level of the plot area was greater at the start of the experiment than at the end. The NT plots actually lost a total of −1.2 Mg C ha−1, the CP lost −9.9 Mg C ha−1, and the MP lost −8.2 Mg C ha−1 during the 24-year study. The long-term productivity of NT compared favorably with that of MP and CP systems.

  14. [Effects of long-term tillage measurements on soil aggregate characteristic and microbial diversity].

    Science.gov (United States)

    Li, Jing; Wu, Hui-Jun; Wu, Xue-Ping; Cai, Dian-Xiong; Yao, Yu-Qing; Lü, Jun-Jie; Tian, Yun-Long

    2014-08-01

    Soil aggregate stability and microbial diversity play important roles in nutrient recycling in soil-crop systems. This study investigated the impacts of different soil tillage systems on soil aggregation and soil microbial diversity based on a 15-year long-term experiment on loess soil in Henan Province of China. Treatments included reduced tillage (RT), no-tillage (NT), sub-soiling with mulch (SM), wheat-peanut two crops (TC), and conventional tillage (CT). Soil aggregates were separated by wet sieving method, and soil microbial (bacterial, archaeal and fungal) diversity was examined by using the techniques of denaturing gradient gel electrophoresis (PCR-DGGE) analysis. The results showed that water-stable macroaggregates concent (R0.25) and the mean mass diameter (MWD) in the surface soil significantly increased under NT, SM and TC, R0.25 increased by 21.5%, 29.5% and 69.2%, and MWD increased by 18.0%, 12.2% and 50.4%, respectively, as compared with CT. Tillage practices caused changes in bacterial, archaeal and fungal community compositions. With NT, SM and TC, the bacterial, archaeal and fungal Shannon indices increased by 0.3%, 0.3%, and 0.6%, and 20.2%, 40.5%, and 49.1%, and 23.7%, 19.5%, and 25.8%, respectively, as compared with CT. Both bacterial and archaeal Shannon indices were significantly correlated with the indices of R0.25 and MWD, while the fungal Shannon index was not significantly correlated with these two indices. In conclusion, conservation tillage, including NT and SM, and crop rotation, including TC, improved soil aggregation and soil microbial diversity.

  15. Effects of nitrogen fertilizer sources and tillage practices on greenhouse gas emissions in paddy fields of central China

    Science.gov (United States)

    Zhang, Z. S.; Chen, J.; Liu, T. Q.; Cao, C. G.; Li, C. F.

    2016-11-01

    The effects of nitrogen (N) fertilizer sources and tillage practices on greenhouse gas (GHG) emission have been well elucidated separately. However, it is still remained unclear regarding the combined effects of N fertilization and tillage practices on the global warming potential (GWP) and net ecosystem economic budget (NEEB) in paddy fields. In this paper, a 2-year field experiment was performed to investigate the effects of N fertilizer sources (N0, no N; IF, 100% N from chemical fertilizer; SRIF, 50% N from slow-release fertilizer and 50% N from chemical fertilizer; OF, 100% N from organic fertilizer; OFIF, 50% N from organic fertilizer and 50% N from chemical fertilizer) and tillage practices (CT, conventional intensive tillage; NT, no-tillage) on the emissions of methane (CH4) and nitrous oxide (N2O), GWP, greenhouse gas intensity (GHGI), and NEEB in paddy fields of central China. Compared with N0 treatment, IF, SRIF, OF and OFIF treatments greatly enhanced the cumulative seasonal CH4 emissions (by 54.7%, 41.7%, 51.1% and 66.0%, respectively) and N2O emissions (by 164.5%, 93.4%, 130.2% and 251.3%, respectively). NT treatment significantly decreased the GWP and GHGI compared with CT treatment. On the other hand, NT treatment significantly decreased CH4 emissions by 8.5-13.7%, but did not affect N2O emissions relative to CT treatment. Application of N fertilizers significantly increased GWP and GHGI. It was worth noting that the combined treatment of OFIF and NT resulted in the second-highest GWP and GHGI and the largest NEEB among all treatments. Therefore, our results suggest that OFIF combined with NT is an eco-friendly strategy to optimize the economic and environmental benefits of paddy fields in central China. Although the treatment of SRIF plus NT showed the lowest GWP and GHGI and the highest grain yield among all treatments, it led to the lowest NEEB due to its highest fertilizer cost. These results indicate that the government should provide

  16. Combined effects of constant versus variable intensity simulated rainfall and reduced tillage management on cotton preemergence herbicide runoff.

    Science.gov (United States)

    Potter, Thomas L; Truman, Clint C; Strickland, Timothy C; Bosch, David D; Webster, Theodore M; Franklin, Dorcas H; Bednarz, Craig W

    2006-01-01

    Pesticide runoff research relies heavily on rainfall simulation experiments. Most are conducted at a constant intensity, i.e., at a fixed rainfall rate; however, large differences in natural rainfall intensity is common. To assess implications we quantified runoff of two herbicides, fluometuron and pendimethalin, and applied preemergence after planting cotton on Tifton loamy sand. Rainfall at constant and variable intensity patterns representative of late spring thunderstorms in the Atlantic Coastal Plain region of Georgia (USA) were simulated on 6-m2 plots under strip- (ST) and conventional-tillage (CT) management. The variable pattern produced significantly higher runoff rates of both compounds from CT but not ST plots. However, on an event-basis, runoff totals (% applied) were not significantly different, with one exception: fluometuron runoff from CT plots. There was about 25% more fluometuron runoff with the variable versus the constant intensity pattern (P = 0.10). Study results suggest that conduct of simulations using variable intensity storm patterns may provide more representative rainfall simulation-based estimates of pesticide runoff and that the greatest impacts will be observed with CT. The study also found significantly more fluometuron in runoff from ST than CT plots. Further work is needed to determine whether this behavior may be generalized to other active ingredients with similar properties [low K(oc) (organic carbon partition coefficient) approximately 100 mL g(-1); high water solubility approximately 100 mg L(-1)]. If so, it should be considered when making tillage-specific herbicide recommendations to reduce runoff potential.

  17. Relative Efficiency of Different Tillage Practices and Their Effect on Soil Physical Properties under Semi-Arid Climate of Tandojam, Pakistan

    Directory of Open Access Journals (Sweden)

    Naimatullah Leghari

    2016-04-01

    Full Text Available Tillage practices affect physical properties of soil that are crucial for better crop production. The study was carried out to compare the efficiency of two different tillage implements and their effect on some soil physical properties. The tillage implements included cultivator and disc plow. The soil properties viz. soil moisture, bulk density and infiltration rate were determined before and after the tillage practices. However, the efficiency of tillage operation including operating speed, travel reduction and fuel consumption were taken during the tillage operation. The comparative analysis showed that the cultivator was better in reducing soil bulk density (12-18% along with increasing the infiltration rate up to 61.5% and conserving soil moisture up to 95%. The disc plow, on the other hand, reduced the bulk density of soil more effectively with up to 21% efficiency and enhancing soil porosity (23%. However, disc plow was less efficient in increasing infiltration rate (38% and conserving soil moisture (87-90%. Comparatively higher fuel consumption (23.3 L hr-1 was observed in operating disc plow with less operating speed (4.1 km hr-1 and higher travel reduction (27.5%. On the other hand, higher cultivator operating speed (4.76km hr-1 was observed with less travel reduction (21.8% and fuel consumption (14.9 Lhr-1. The cultivator, being more economical and having good effects on soil properties, was the best option for tillage operations in the clay soils of cotton-wheat rotation system under semi-arid climate of Tandojam, Pakistan.

  18. Effects of Conventional and Conservation Tillage on Soil Hydraulic Properties of a Silty-loamy Soil

    DEFF Research Database (Denmark)

    Wahl, Niels Arne; Bens, O.; Buczko, U.

    2004-01-01

    , the methods of visual inventarization of stained and unstained macropores and infiltration measurements with an infiltrometer were applied to the macropore system. Dye tracer experiments with methylene blue as tracer agent yielded a penetration depth of 120 cm on the conservation tillage plot while...

  19. A VESS assessment of tillage and stover harvest effects in Iowa, U.S.A.GE

    Science.gov (United States)

    Soil quality/health reflects physical, chemical, and biological properties, processes, and interactions occurring in response to management practices such as tillage and crop residue removal. Increased global interest in harvesting crop residues for bioenergy, animal feed, or other bio-products has ...

  20. Long-term tillage effects on soil metolachlor sorption and desorption behavior.

    Science.gov (United States)

    Ding, Guangwei; Novak, Jeffrey M; Herbert, Stephen; Xing, Baoshan

    2002-09-01

    Sorption and desorption are two important processes that influence the amount of pesticides retained by soils. However, the detailed sorption mechanisms as influenced by soil tillage management are unclear. This study examined the sorption and desorption characteristics of metolachlor [2-chloro-N-(2-ethyl-6-methyphenyl)-N-(2-methoxy-1-methylethyl)-acetamide] using the soil samples collected from the long-term conservation tillage (CnT) and conventional tillage (CT) research plots established in 1979 in Darlinton, SC. Humic acid (HA) and humin were extracted from the soils and used in the sorption experiments along with the whole soil samples. The sorption experiments were conducted using a batch-equilibration method. Three sequential desorption rinses were carried out following the sorption experiments. By comparing metolachlor sorption and desorption results we observed hysteresis for all soil samples and their organic matter fractions. Sorption nonlinearity (N) and hysteresis were dependent on the structure and composition of soil organic matter (SOM), e.g., Freundlich isotherm exponents (N) of HA and humin from CnT were higher than those of CT treatment, which may be related to high aromaticity of SOM fractions in CT treatment. Sorption capacity (K'f) was positively correlated with soil organic carbon (SOC) content. These results show that long-term tillage management can greatly affect metolachlor sorption and desorption behavior probably by qualitative differences in the structural characteristics of the humic substances.

  1. Tillage effects on soil organic matter in density fractions of a Cerrado Oxisol

    NARCIS (Netherlands)

    Roscoe, R.; Buurman, P.

    2003-01-01

    Reclamation of Brazilian cerrados (savannas) has been intensified in the last decades, with implications for soil quality and soil organic matter (SOM) dynamics. Studying the impact of different tillage systems is essential to define better strategies for land use in Cerrado, which may favor C seque

  2. Effects of Conventional and Conservation Tillage on Soil Hydraulic Properties of a Silty-loamy Soil

    DEFF Research Database (Denmark)

    Wahl, Niels Arne; Bens, O.; Buczko, U.

    2004-01-01

    a minimum macropore radius of 0.5 mm, range between 0.02% and 0.1%, about one order of magnitude lower than the figure obtained from visual inventarization. The results indicate a greater continuity and connectivity of the macropore system for silty soils with conservation tillage systems. Therefore...

  3. Tillage and crop residue effects on rainfed wheat and maize production in Nortern China

    NARCIS (Netherlands)

    Wang Xiaobin,; Wu Huijin,; Dai Kuai,; Zhang Dingchen,; Feng Donghui,; Zhao Quansheng,; Wu Xueping,; Jin Ke,; Cai Diangxiong,; Oenema, O.; Hoogmoed, W.B.

    2012-01-01

    Dryland farming in the dry semi-humid regions of northern China is dominated by mono-cropping systems with mainly maize (Zea mays L.) or wheat (Triticum aestivum), constrained by low and variable rainfall, and by improper management practices. Addressing these problems, field studies on tillage and

  4. 不同施肥与耕作处理对黑土POM-C的影响研究%Effect of Different Fertilization and Tillage Treatments on POM-C in Black soil

    Institute of Scientific and Technical Information of China (English)

    史奕; 鲁彩艳; 郑靖; 陈欣

    2002-01-01

    Based on two long term fertilization(1985 - ) and tillage( 1990- ) experiment, the effect of fertilization and tillage on soil particulate organic matter carbon(POM-C) and total organic carbon(TOC) were studied. The results indicated that under the conventional tillage condition, the largest POM-C and TOC content in 0 ~ 20ca soil layer was found in the treatment of N and P fertilizers + recycled nutrients among six fertilization simulated models. As blent residue into the whole 0~20cm topsoil, POM-C content of the deep ploughing treatment was higher than other treatments. The order was:association,prevalent and rotary tillage.

  5. [Effects of conservation tillage on soil water conservation and crop yield of winter wheat-spring maize rotation field in Weibei highland].

    Science.gov (United States)

    Zhang, Li-hua; Li, Jun; Jia, Zhi-kuan; Liu, Bing-feng; Zhao, Hong-li; Shang, Jin-xia

    2011-07-01

    A field experiment was conducted in 2007-2010 to study the effects of no-tillage, subsoiling, and deep-ploughing combined with balanced fertilization, traditional fertilization, and no (or lower amount) fertilization on the soil water storage, crop yield, water use efficiency (WUE), and economic return of winter wheat-spring maize rotation field in Weibei highland. Among the tillage measures, no-tillage in fallow period had the best effect in soil water conservation, followed by sub-soiling, and deep-ploughing. The average water storage in 0-200 cm soil layer in crop growth period under no-tillage and sub-soiling was 6.7% and 1.9% higher than that under deep-ploughing, respectively. Under the balanced, traditional, and no (or lower amount) fertilizations, subsoiling all showed the highest yield, WUE, and economic return, with the best effect under balanced fertilization. The three-year crop yield under sub-soiling combined with balanced fertilization was 6909, 9689, and 5589 kg x hm(-2), WUE was 18.5, 25.2, and 23.0 kg x hm(-2) x mm(-1), and economic return was 5034, 5045, and 7098 yuan x hm(-2), respectively. It was suggested that balanced fertilization combined with sub-soiling had the best effect in soil water conservation and yield- and income increase, being the more appropriate fertilization and tillage mode for the wheat-maize rotation field in Weibei highland.

  6. Effect of Different Tillage Management on Soil Physical Properties and Maize Yield%不同耕作方式对玉米田土壤物理性质及产量的影响

    Institute of Scientific and Technical Information of China (English)

    范继征; 闫飞燕; 石达金; 吕巨智; 张玉; 钟昌松; 程伟东; 刘永红

    2016-01-01

    By the mensuration and analysis of soil bulk density, soil total porosity, soil moisture content, soil moisture capacity and maize yield, the effects of subsoiling and rotary tilling, subsoiling and no-tillage, conventional rotary tillage and no-tillage on soil physical characters and maize yield through field experiments in a single fertil⁃ization were researched. The results showed that the effects of tillage methods on the soil bulk density and soil mois⁃ture content were different, with the order of subsoiling and rotary tilling, subsoiling and no-tillage, conventional ro⁃tary tillage and no-tillage. The effects of tillage methods on the soil total porosity were different, with the order of subsoiling and no-tillage, no-tillage, subsoiling and rotary tilling and conventional rotary tillage. The effects of till⁃age methods on the soil moisture capacity were different, with the order of subsoiling and no-tillage, conventional ro⁃tary tillage, subsoiling and rotary tilling and no-tillage. Finally the tillage managements have a great effect on maize yield, with order of subsoiling and no-tillage, no-tillage, conventional rotary tillage, subsoiling and rotary tilling. There was a significant difference between subsoiling and no-tillage, no-tillage and conventional rotary tillage, sub⁃soiling and rotary tilling. The production of subsoiling and no-tillage, increased 15.68% than conventional rotary tillage, achieved 6 829.73 kilograms per hectare.%通过对土壤容重、总孔隙度、含水量、田间持水量及玉米产量的测定和分析,研究一次性施肥条件下深松-旋耕、深松-免耕、常规旋耕和免耕不同耕作方式对土壤物理性状及玉米产量的影响。结果表明,不同耕作方式对土壤容重和土壤含水量的影响效果为深松-旋耕>深松-免耕>常规旋耕>免耕;对土壤持水量的影响效果为深松-免耕>常规旋耕>深松-旋耕>免耕;对玉米产量的影响效果为深松-免

  7. Evaluating the Effect of Tillage on Carbon Sequestration Using the Minimum Detectable Difference Concept

    Institute of Scientific and Technical Information of China (English)

    X. M. YANG; C. F. DRURY; M. M. WANDER; B. D. KAY

    2008-01-01

    Three long-term field trials in humid regions of Canada and the USA were used to evaluate the influence of soil depth and sample numbers on soil organic carbon (SOC) sequestration in no-tillage (NT) and moldboard plow (MP) corn (Zea mays L.) and soybean (Glycine max L.) production systems. The first trial was conducted on a Maryhill silt loam (Typic Hapludalf) at Elora, Ontario, Canada, the second on a Brookston clay loam (Typic Argiaquoll) at Woodslee, Ontario,Canada, and the third on a Thorp silt loam (Argiaquic Argialboll) at Urbana, Illinois, USA. No-tillage led to significantly higher SOC concentrations in the top 5 cm compared to MP at all 3 sites. However, NT resulted in significantly lower SOC in sub-surface soils as compared to MP at Woodslee (10-20 cm, P = 0.01) and Urbana (20-30 cm, P < 0.10).No-tillage had significantly more SOC storage than MP at the Elora site (3.3 Mg C ha-1) and at the Woodslee site (6.2Mg C ha-1) on an equivalent mass basis (1350 Mg ha-1 soil equivalent mass). Similarly, NT had greater SOC storage than MP at the Urbana site (2.7 Mg C ha-1) on an cquivalent mass basis of 675 Mg ha-1 soil. However, these differences disappcared when the entire plow layer was evaluated for both the Woodslee and Urbana sites as a result of the higher SOC concentrations in MP than in NT at depth. Using the minimum detectable difference technique, we observed that up to 1500 soil sample per tillage treatment comparison will have to be collected and analyzed for the Elora and Woodslee sites and over 40 soil samples per tillage treatment comparison for the Urbana to statistically separate significant differences in the SOC contents of sub-plow depth soils. Therefore, it is impracticable, and at the least prohibitively expensive, to detect tillage-induced differences in soil C beyond the plow layer in various soils.

  8. Crop response to deep tillage - a meta-analysis

    Science.gov (United States)

    Schneider, Florian; Don, Axel; Hennings, Inga; Schmittmann, Oliver; Seidel, Sabine J.

    2017-04-01

    Subsoil, i.e. the soil layer below the topsoil, stores tremendous stocks of nutrients and can keep water even under drought conditions. Deep tillage may be a method to enhance the plant-availability of subsoil resources. However, in field trials, deep tillage effects on crop yields were inconsistent. Therefore, we conducted a meta-analysis of crop yield response to subsoiling, deep ploughing and deep mixing of soil profiles. Our search resulted in 1530 yield comparisons following deep and conventional control tillage on 67 experimental cropping sites. The vast majority of the data derived from temperate latitudes, from trials conducted in the USA (679 observations) and Germany (630 observations). On average, crop yield response to deep tillage was slightly positive (6% increase). However, individual deep tillage effects were highly scattered including about 40% yield depressions after deep tillage. Deep tillage on soils with root restrictive layers increased crop yields about 20%, while soils containing >70% silt increased the risk of yield depressions following deep tillage. Generally, deep tillage effects increased with drought intensity indicating deep tillage as climate adaptation measure at certain sites. Our results suggest that deep tillage can facilitate the plant-availability of subsoil nutrients, which increases crop yields if (i) nutrients in the topsoil are growth limiting, and (ii) deep tillage does not come at the cost of impairing topsoil fertility. On sites with root restrictive soil layers, deep tillage can be an effective measure to mitigate drought stress and improve the resilience of crops. However, deep tillage should only be performed on soils with a stable structure, i.e. <70% silt content. We will discuss the contribution of deep tillage options to enhance the sustainability of agricultural production by facilitating the uptake of nutrients and water from the subsoil.

  9. Effect of cover crops on emergence and growth of carrot (Daucus carota L. in no-plow and traditional tillage

    Directory of Open Access Journals (Sweden)

    Marzena Błażewicz-Woźniak

    2015-03-01

    Full Text Available The aim of the experiment was to determine the influence of cover crop biomass incorporated into the soil at different times and using different treatments on carrot emergence and growth. 7 species of cover crops were included in the study: Secale cereale, Avena sativa, Vicia sativa, Sinapis alba, Phacelia tanacetifolia, Fagopyrum esculentum, and Helianthus annuus.  Number of emerged carrot plants significantly depended on the cover crop used and on the method of pre-winter and spring pre-sowing tillage. Carrot emerged best after a rye or oats cover crop. Regardless of the cover crop species used, the largest number of carrots emerged in cultivation on ridges. In other variants of no-plow tillage, number of seedlings was significantly lower and did not differ from that under traditional plow tillage. The highest leaf rosettes were formed by carrot growing after a rye or oats cover crop. The highest rosettes were produced by carrots in the treatments where tillage was limited to the use of a tillage implement in spring and the lowest ones after pre-winter plowing. The effect of tillage on the emergence and height of carrot leaves largely depended on weather conditions in the successive years of the study. The largest number of leaves was found in carrots grown after a buckwheat cover crop and in cultivation without cover crop, while the smallest one after phacelia and white mustard. Carrots produced the largest number of leaves after a sunflower cover crop and the use of a tillage implement in spring, while the number of leaves was lowest when the mustard biomass was incorporated into the soil in spring. The use of cover crops significantly increased the mass of leaves produced by carrot as compared to the cultivation without cover crop. The largest mass of leaves was produced by carrots grown after the phacelia and mustard cover crops. Conventional plow tillage and pre-winter tillage using a stubble cultivator promoted an increase in the mass

  10. Fertilizer source and tillage effects on yield-scaled nitrous oxide emissions in a corn cropping system.

    Science.gov (United States)

    Venterea, Rodney T; Bijesh, Maharjan; Dolan, Michael S

    2011-01-01

    Management practices such as fertilizer or tillage regime may affect nitrous oxide (N₂O) emissions and crop yields, each of which is commonly expressed with respect to area (e.g., kg N ha or Mg grain ha). Expressing N₂O emissions per unit of yield can account for both of these management impacts and might provide a useful metric for greenhouse gas inventories by relating N₂O emissions to grain production rates. The objective of this study was to examine the effects of long-term (>17 yr) tillage treatments and N fertilizer source on area- and yield-scaled N₂O emissions, soil N intensity, and nitrogen use efficiency for rainfed corn ( L.) in Minnesota over three growing seasons. Two different controlled-release fertilizers (CRFs) and conventional urea (CU) were surface-applied at 146 kg N ha(-1) several weeks after planting to conventional tillage (CT) and no-till (NT) treatments. Yield-scaled emissions across all treatments represented 0.4 to 1.1% of the N harvested in the grain. Both CRFs reduced soil nitrate intensity, but not N₂O emissions, compared with CU. One CRF, consisting of nitrification and urease inhibitors added to urea, decreased N₂O emissions compared with a polymer-coated urea (PCU). The PCU tended to have lower yields during the drier years of the study, which increased its yield-scaled N₂O emissions. The overall effectiveness of CRFs compared with CU in this study may have been reduced because they were applied several weeks after corn was planted. Across all N treatments, area-scaled N₂O emissions were not significantly affected by tillage. However, when expressed per unit yield of grain, grain N, or total aboveground N, N₂O emissions with NT were 52, 66, and 69% greater, respectively, compared with CT. Thus, in this cropping system and climate regime, production of an equivalent amount of grain using NT would generate substantially more N₂O compared with CT.

  11. Temperature and water pressure head effects on the degradation of the diketonitrile metabolite of isoxaflutole in a loamy soil under two tillage systems

    Energy Technology Data Exchange (ETDEWEB)

    Alletto, Lionel [Universite de Toulouse - Ecole d' ingenieurs de Purpan, Agronomy Department, 75, voie du TOEC BP 57 611, 31 076 Toulouse Cedex 3 (France); UMR 1091 INRA/AgroParisTech Environment and Arable Crops, Institut National de la Recherche Agronomique/Institut National des Sciences et Industries du Vivant et de l' Environnement, BP 01, 78 850 Thiverval-Grignon (France)], E-mail: lionel.alletto@purpan.fr; Benoit, Pierre [UMR 1091 INRA/AgroParisTech Environment and Arable Crops, Institut National de la Recherche Agronomique/Institut National des Sciences et Industries du Vivant et de l' Environnement, BP 01, 78 850 Thiverval-Grignon (France)], E-mail: benoit@grignon.inra.fr; Bergheaud, Valerie [UMR 1091 INRA/AgroParisTech Environment and Arable Crops, Institut National de la Recherche Agronomique/Institut National des Sciences et Industries du Vivant et de l' Environnement, BP 01, 78 850 Thiverval-Grignon (France)], E-mail: bergheau@grignon.inra.fr; Coquet, Yves [UMR 1091 INRA/AgroParisTech Environment and Arable Crops, Institut National de la Recherche Agronomique/Institut National des Sciences et Industries du Vivant et de l' Environnement, BP 01, 78 850 Thiverval-Grignon (France)], E-mail: Yves.Coquet@agroparistech.fr

    2008-12-15

    Laboratory studies were conducted to evaluate the effects of temperature and water pressure head on the degradation of the diketonitrile metabolite (DKN) of isoxaflutole during 84 d in samples collected in a loamy soil under conventional (CT) and conservation (MT) tillage systems. Soil temperature was the major factor controlling DKN degradation in the two tillage systems. The shortest half-lives (T{sub 1/2}) were measured in the seedbed samples under MT at 25 deg. C and -33 cm water pressure head. We found that mouldboard ploughing under CT was responsible for the spatial variability of herbicide degradation properties, whereas under MT herbicide degradation was associated to the vertical distribution of organic matter. - Tillage practices influence the spatial variability of diketonitrile degradation in soil and its sensitivity to pedoclimatic conditions.

  12. Nitrogen, tillage, and crop rotation effects on nitrous oxide emissions from irrigated cropping systems.

    Science.gov (United States)

    Halvorson, Ardell D; Del Grosso, Stephen J; Reule, Curtis A

    2008-01-01

    We evaluated the effects of irrigated crop management practices on nitrous oxide (N(2)O) emissions from soil. Emissions were monitored from several irrigated cropping systems receiving N fertilizer rates ranging from 0 to 246 kg N ha(-1) during the 2005 and 2006 growing seasons. Cropping systems included conventional-till (CT) continuous corn (Zea mays L.), no-till (NT) continuous corn, NT corn-dry bean (Phaseolus vulgaris L.) (NT-CDb), and NT corn-barley (Hordeum distichon L.) (NT-CB). In 2005, half the N was subsurface band applied as urea-ammonium nitrate (UAN) at planting to all corn plots, with the rest of the N applied surface broadcast as a polymer-coated urea (PCU) in mid-June. The entire N rate was applied as UAN at barley and dry bean planting in the NT-CB and NT-CDb plots in 2005. All plots were in corn in 2006, with PCU being applied at half the N rate at corn emergence and a second N application as dry urea in mid-June followed by irrigation, both banded on the soil surface in the corn row. Nitrous oxide fluxes were measured during the growing season using static, vented chambers (1-3 times wk(-1)) and a gas chromatograph analyzer. Linear increases in N(2)O emissions were observed with increasing N-fertilizer rate, but emission amounts varied with growing season. Growing season N(2)O emissions were greater from the NT-CDb system during the corn phase of the rotation than from the other cropping systems. Crop rotation and N rate had more effect than tillage system on N(2)O emissions. Nitrous oxide emissions from N application ranged from 0.30 to 0.75% of N applied. Spikes in N(2)O emissions after N fertilizer application were greater with UAN and urea than with PCU fertilizer. The PCU showed potential for reducing N(2)O emissions from irrigated cropping systems.

  13. Effects of Conservation Tillage on Topsoil Microbial Metabolic Characteristics and Organic Carbon within Aggregates under a Rice (Oryza sativa L.)-Wheat (Triticum aestivum L.) Cropping System in Central China.

    Science.gov (United States)

    Guo, Li-Jin; Lin, Shan; Liu, Tian-Qi; Cao, Cou-Gui; Li, Cheng-Fang

    2016-01-01

    Investigating microbial metabolic characteristics and soil organic carbon (SOC) within aggregates and their relationships under conservation tillage may be useful in revealing the mechanism of SOC sequestration in conservation tillage systems. However, limited studies have been conducted to investigate the relationship between SOC and microbial metabolic characteristics within aggregate fractions under conservation tillage. We hypothesized that close relationships can exist between SOC and microbial metabolic characteristics within aggregates under conservation tillage. In this study, a field experiment was conducted from June 2011 to June 2013 following a split-plot design of a randomized complete block with tillage practices [conventional intensive tillage (CT) and no tillage (NT)] as main plots and straw returning methods [preceding crop residue returning (S, 2100-2500 kg C ha-1) and removal (NS, 0 kg C ha(-1))] as subplots with three replications. The objective of this study was to reveal the effects of tillage practices and residue-returning methods on topsoil microbial metabolic characteristics and organic carbon (SOC) fractions within aggregates and their relationships under a rice-wheat cropping system in central China. Microbial metabolic characteristics investigated using the Biolog system was examined within two aggregate fractions (>0.25 and 0.25 aggregate, and 0.25 mm aggregate (11.3%), and 0.25 mm aggregate, and 0.25 mm aggregate, and tillage (NT and S) increased microbial metabolic activities and Shannon index in >0.25 and 0.25 mm aggregate in the upper (0-5 cm) soil layer under conservation tillage systems, as well as directly and indirectly by promoting DOC and MBC in tillage increased SOC in aggregates in the topsoil by improving microbial metabolic activities.

  14. The Effects of Different Tillage Systems on Soil Hydrology and Erosion in Southeastern Brazil

    Science.gov (United States)

    Bertolino, A. V. F. A.; Fernandes, N. F.; Souza, A. P.; Miranda, J. P.; Rocha, M. L.

    2009-04-01

    Conventional tillage usually imposes a variety of modifications on soil properties that can lead to important changes in the type and magnitude of the hydrological processes that take place at the upper portion of the soil profile. Plough pan formation, for example, is considered to be an important consequence of conventional tillage practices in southeastern Brazil, decreasing infiltration rates and contributing to soil erosion, especially in steep slopes. In order to characterize the changes in soil properties and soil hydrology due to the plough pan formation we carried out detailed investigations in two experimental plots in Paty do Alferes region, located in the hilly landscape of Serra do Mar in southeastern Brazil, close to Rio de Janeiro city. Farming activities are very important in this area, in particular the ones related to the tomato production. The local hilly topography with short and steep hillslopes, as well as an average annual rainfall of almost 2000 mm, favor surface runoff and the evolution of rill and gully erosion. The two runoff plots are 22m long by 4m wide and were installed side by side along a representative hillslope, both in terms of soil (Oxisol) and steepness. At the lower portion of each plot there is a collecting trough connected by a PVC pipe to a 500 and 1000 liters sediment storage boxes. Soil tillage treatments used in the two plots were: Conventional Tillage (CT), with one plowing using disc-type plow (about 18 cm depth) and one downhill tractor leveling, in addition to burning residues from previous planting; and Minimum Tillage (MT), which did not allow burning residues from previous planting and preserved a vegetative cover between plantation lines. Runoff and soil erosion measurements were carried out in both plots immediately after each rainfall event. In order to characterize soil water movements under the two tillage systems (CT and MT), 06 nests of tensiometers and 04 nests of Watermark sensors were installed in each

  15. Quantifying truncation errors in effective field theory

    CERN Document Server

    Furnstahl, R J; Phillips, D R; Wesolowski, S

    2015-01-01

    Bayesian procedures designed to quantify truncation errors in perturbative calculations of quantum chromodynamics observables are adapted to expansions in effective field theory (EFT). In the Bayesian approach, such truncation errors are derived from degree-of-belief (DOB) intervals for EFT predictions. Computation of these intervals requires specification of prior probability distributions ("priors") for the expansion coefficients. By encoding expectations about the naturalness of these coefficients, this framework provides a statistical interpretation of the standard EFT procedure where truncation errors are estimated using the order-by-order convergence of the expansion. It also permits exploration of the ways in which such error bars are, and are not, sensitive to assumptions about EFT-coefficient naturalness. We first demonstrate the calculation of Bayesian probability distributions for the EFT truncation error in some representative examples, and then focus on the application of chiral EFT to neutron-pr...

  16. Impact of different cropping conditions and tillage practices on the soil fungal abundance of a Phaeozem luvico

    Directory of Open Access Journals (Sweden)

    Romina P. Gómez

    2015-06-01

    Full Text Available Fungal diversity seems to be a good indicator of ecosystem disturbance and functioning. The purpose of this work was to quantify the fungal population as a sensitive indicator of the changes caused by stubble placement in two tillage systems: reduced tillage (RT and conventional tillage (CT with and without cropping. To this end, we determined the effect of soil disturbances such as N fertilization, tillage practice, and cropped area on the soil fungal communities of a Phaeozem luvico of the El Salado river basin (Argentina. Soil samples (at 0-10 cm depth were collected from a field cultivated with wheat at post-harvest, before sowing and at tillering. The relative abundance of individuals of the fungal population was studied on Nash Snyder and Oxgall agar media after different treatments and assessed as colony forming units (CFU/g of soil. The diversity of the fungal population was studied by Shannon´s index (H. The tillage system showed a marked effect only at post-harvest and the number of propagules was highest under RT for both culture media. The largest values of H were found only at post-harvest when Oxgall agar was used. A significant decrease in the values of H was observed when CT and high fertilization was applied in the wheat cropped area. The relative abundance of individuals of the fungal population was different in soils under the different tillage practices.

  17. Characterization of Leaf Photosynthetic Properties for No-Tillage Rice

    Institute of Scientific and Technical Information of China (English)

    CHEN Song; XIA Guo-mian; ZHAO Wei-ming; WU Fei-bo; ZHANG Guo-ping

    2007-01-01

    A study was conducted to determine the influence of no-tillage cultivation on leaf photosynthesis of rice plants under field conditions. Experiments with the treatments, no-tillage and conventional tillage were carried out at three locations (Jiaxing, Hangzhou,and Xiaoshan, Zhejiang Province, China) for two years (2005 and 2006). Grain yield was constant in Jiaxing, but slightly higher in Hangzhou and Xiaoshan under no-tillage cultivation than that under conventional cultivation. In comparison with the conventional cultivation, no-tillage cultivation showed less biomass accumulation before heading and higher capacity of matter production during grain filling. A significantly higher leaf net photosynthetic rate was observed for the plants under no-tillage than for those under conventional tillage. The fluorescence parameter (Fv/Fm) in leaf did not show any difference between the two cultivations. The effect of cultivation management on transpiration rate (Tr) and SPAD value of rice leaf was dependent on the location and year.

  18. Characterization of Leaf Photosynthetic Properties for No-Tillage Rice

    Directory of Open Access Journals (Sweden)

    Song CHEN

    2007-12-01

    Full Text Available A study was conducted to determine the influence of no-tillage cultivation on leaf photosynthesis of rice plants under field conditions. Experiments with the treatments, no-tillage and conventional tillage were carried out at three locations (Jiaxing, Hangzhou, and Xiaoshan, Zhejiang Province, China for two years (2005 and 2006. Grain yield was constant in Jiaxing, but slightly higher in Hangzhou and Xiaoshan under no-tillage cultivation than that under conventional cultivation. In comparison with the conventional cultivation, no-tillage cultivation showed less biomass accumulation before heading and higher capacity of matter production during grain filling. A significantly higher leaf net photosynthetic rate was observed for the plants under no-tillage than for those under conventional tillage. The fluorescence parameter (Fv/Fm in leaf did not show any difference between the two cultivations. The effect of cultivation management on transpiration rate (Tr and SPAD value of rice leaf was dependent on the location and year.

  19. [Short-term effects of different tillage modes combined with straw-returning on the soil labile organic carbon components in a farmland with rice-wheat double cropping].

    Science.gov (United States)

    Yang, Min-Fang; Zhu, Li-Qun; Han, Xin-Zhong; Gu, Ke-Jun; Hu, Nai-Juan; Bian, Xin-Min

    2013-05-01

    A two-year (2009-2011) field experiment was conducted to study the effects of different tillage modes, straw-returning, and their interactions on the soil total organic carbon (TOC) and labile organic carbon (LOC) components (easily oxidizable organic carbon (EOC), water-soluble organic carbon (WSOC), and microbial biomass carbon (MBC)) at the soil depths of 0-7, 7-14, and 14-21 cm in a farmland with rice-wheat double cropping. In all treatments of straw-returning, the TOC and LOC contents in each soil layer were significantly higher than those without straw-returning. Under plowing tillage, the MBC content in 0-7 cm soil layer was significantly higher than that under rotary tillage, but the EOC content was in adverse. Rotary tillage made the TOC content in 7 - 14 cm soil layer being significantly higher, as compared with plowing tillage. The TOC, WSOC, and MBC contents in 14-21 cm soil layer under plowing tillage were significantly higher than those under rotary tillage. Plowing tillage combined with rice and wheat straws-returning made the soil TOC content being higher than the other treatments.

  20. Soil carbon fractions under maize-wheat system: effect of tillage and nutrient management.

    Science.gov (United States)

    Sandeep, S; Manjaiah, K M; Pal, Sharmistha; Singh, A K

    2016-01-01

    Soil organic carbon plays a major role in sustaining agroecosystems and maintaining environmental quality as it acts as a major source and sink of atmospheric carbon. The present study aims to assess the impact of agricultural management practices on soil organic carbon pools in a maize-wheat cropping system of Indo-Gangetic Plains, India. Soil samples from a split plot design with two tillage systems (bed planting and conventional tillage) and six nutrient treatments (T1 = control, T2 = 120 kg urea-N ha(-1), T3 = T2 (25 % N substituted by FYM), T4 = T2 (25 % N substituted by sewage sludge), T5 = T2 + crop residue, T6 = 100 % organic source (50 % FYM + 25 % biofertilizer + 25 % crop residue) were used for determining the organic carbon pools. Results show that there was a significant improvement in Walkley and Black carbon in soil under integrated and organic nutrient management treatments. KMnO4-oxidizable carbon content of soil varied from 0.63 to 1.50 g kg(-1) in soils and was found to be a better indicator for monitoring the impact of agricultural management practices on quality of soil organic carbon than microbial biomass carbon. Tillage and its interaction were found to significantly influence only those soil organic carbon fractions closely associated with aggregate stability viz, labile polysaccharides and glomalin. The highest amount of C4-derived carbon was found to be in plots receiving recommended doses of N as urea (29 %) followed by control plots (25 %). The carbon management index ranged between 82 to 195 and was better in integrated nutrient sources than ones receiving recommended doses of nutrients through mineral fertilizers alone.

  1. Tillage and phosphorus management effects on enzyme-labile bioactive phosphorus availability in brazilian cerrado oxisols and temperature zone typic hapludults

    Science.gov (United States)

    Tillage management practices have a direct effect on the behavior and availability of soil nutrients. Phosphorus (P) is an essential element in crop growth which can be growth-limiting or an environmental contaminant, if present in excess. Sorption and availability of various soil P forms were eva...

  2. Long-term effect of tillage and manure application on soil organic fractions and crop performance under Sudano-Sahelian conditions

    NARCIS (Netherlands)

    Mando, A.; Ouattara, B.; Sédogo, M.; Stroosnijder, L.; Ouattara, K.; Brussaard, L.; Vanlauwe, B.

    2005-01-01

    Human-induced degradation of natural resources in general and of soil in particular, is a major problem in many regions, including the Sudano-Sahelian zone. The combined effects of tillage and manure application on Lixisol properties and on crop performance were investigated at Saria, Burkina Faso,

  3. 深松和翻耕对旱地小麦花后根系衰老及产量的影响%Effect of Subsoiling Tillage and Ploughing Tillage on the Root Senescence after Anthesis and Yield of Wheat in Dry-land

    Institute of Scientific and Technical Information of China (English)

    李国清; 石岩

    2012-01-01

    为了解深松耕作对小麦根系衰老及产量的影响,以济麦22为材料,通过田间试验,对深松与翻耕条件下旱地小麦花后根系部分生理指标以及籽粒产量进行了比较分析。结果表明,与翻耕处理相比,深松处理小麦花后根系能够保持较高的超氧化物歧化酶活性与硝酸还原酶活性,丙二醛含量较低,可溶性蛋白含量降低缓慢,说明深松处理能够减缓根系的衰老。深松处理的小麦穗数、穗粒数、千粒重高于翻耕处理,其中穗粒数增加达到显著水平,是深松处理增产的主要原因。%The effect of subsoiling tillage and ploughing tillage on the root senescence after anthesis and yield of wheat was studied with Jimai 22 as the test material during 2009-2010 in dry-land condition.The results showed that the activity of superoxide dismutase(SOD) enzyme and nitrate reductase(NR) of wheat roots in the subsoiling tillage treatment were higher than that of in the ploughing tillage treatment.And the content of malondiadehyde(MDA) in the subsoiling tillage treatment was lower than that of in the ploughing tillage treatment.And the content of soluble protein decreased slowly after anthesis in the subsoiling tillage treatment.This indicated that the subsoiling tillage could delay the senescence of wheat root system.The spike number,grain number per spike and thousand grain weights of wheat in the subsoiling tillage treatment were higher than that of in the ploughing tillage treatment,and there was significant difference in the grain number per spike between them,so the subsoiling tillage was benefit to gain higher yield.

  4. Effect of various tillage operations and straw management on the occurence of weeds

    Directory of Open Access Journals (Sweden)

    Ivana Remešová

    2005-01-01

    Full Text Available The weed infestation was assessed in a field experiment at the Research Institute for Folder Crops Ltd., Troubsko near Brno in 2001−2004. Numbers of individual weed species were determined using a counting method on the area of 0.25 m2 in winter wheat stands within the 6-crop rotation (peas, winter wheat, spring barley, oilseed rape, winter wheat, winter wheat in different variants of soil tillage and straw management. The highest weed infestation in all variants was found when winter wheat followed winter wheat. The highest number of weeds was assessed in the variant with stubble tillage to the depth of 0.12−0.15 m, planting with a precision drill and straw chopping. The lowest number of weeds was found in winter wheat after peas in the variant with incorporation of chopped straw using a tiller to 0.12−0.15 m and planting with a drilling combination, and in the variant where chopped straw was sprayed with the BETA-LIQ preparation, incorporation with a tiller to 0.12−0.15 m and planting with a drilling combination.

  5. Long-Term Effects of Rotational Tillage On Visual Evaluation of Soil Structure, Soil Quality and Crop Yield

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Heck, Richard; Deen, Bill

    L.) and R8, (C-C-S-S) corn, corn, soybean (Glycine max L.), soybean. A red clover (Trifolium pretense L.) cover crop was under seeded in oats and spring barley in R6. In 2010, first year corn was grown in R6 and R8. The tillage treatments included no tillage, NT and mouldboard plowing, MP. Topsoil...

  6. Irrigation and cultivar effects in no-till, cover crop, and conventional tillage systems in Arkansas Cotton.

    Science.gov (United States)

    This field experiment was conducted in association with a long term tillage study established in fall 2007 at the Judd Hill Foundation Research Farm in Northeast Arkansas to assess agronomic and environmental impacts of conservation tillage systems. In component studies in 2016 we evaluated performa...

  7. Tillage and vegetative barrier effects on soil conservation and short-term economic benefits in the Central Kenya highlands

    NARCIS (Netherlands)

    Guto, S.N.; Pypers, P.; Vanlauwe, B.; Ridder, de N.; Giller, K.E.

    2011-01-01

    Minimum tillage and vegetative barriers can conserve soil and water resources in the steep-sloping highlands of East Africa but there has been little adoption by smallholder farmers. Soil conservation efficiency and short-term economic benefits provided by tillage and vegetative barriers were assess

  8. Combining Ridge with No-Tillage in Lowland Rice-Based Cropping System:Long-Term Effect on Soil and Rice Yield

    Institute of Scientific and Technical Information of China (English)

    JIANG Xian-Jun; and XIE De-Ti

    2009-01-01

    A tillage method of combining ridge with no-tillage (RNT) was employed in lowland rice-based cropping system to study the long-term effects of RNT on soil profile pattern,soil water stable aggregate distribution,nutrients stratification and yields of rice and post-rice crops.After flooded paddy field (FPF) was practiced with RNT for a long time,soil profile changed from G to A-P-G,and horizon G was shifted to a deeper position in the profile.Also the proportion of macroaggregate (> 2 mm) increased,whereas the proportion of silt and clay (< 0.053 mm) decreased under RNT,indicating a better soil structure that will prevent erosion.RNT helped to control leaching and significantly improved total N,P,K and organic matter in soil.The highest crop yields were found under RNT system every year,and total crop yields were higher under conventional paddy-upland rotation tillage (CR) than under FPF,except in 2003 and 2006 when serious drought occurred.RNT was proven to be a better tillage method for lowland rice-based cropping system.

  9. Effect of rainfall and tillage direction on the evolution of surface crusts, soil hydraulic properties and runoff generation for a sandy loam soil

    Science.gov (United States)

    Ndiaye, Babacar; Esteves, Michel; Vandervaere, Jean-Pierre; Lapetite, Jean-Marc; Vauclin, Michel

    2005-06-01

    The study was aimed at evaluating the effect of rainfall and tillage-induced soil surface characteristics on infiltration and runoff on a 2.8 ha catchment located in the central region of Senegal. This was done by simulating 30 min rain storms applied at a constant rate of about 70 mm h -1, on 10 runoff micro-plots of 1 m 2, five being freshly harrowed perpendicularly to the slope and five along the slope (1%) of the catchment. Runoff was automatically recorded at the outlet of each plot. Hydraulic properties such as capillary sorptivity and hydraulic conductivity of the sandy loam soil close to saturation were determined by running 48 infiltration tests with a tension disc infiltrometer. That allowed the calculation of a mean characteristic pore size hydraulically active and a time to ponding. Superficial water storage capacity was estimated using data collected with an electronic relief meter. Because the soil was subject to surface crusting, crust-types as well as their spatial distribution within micro-plots and their evolution with time were identified and monitored by taking photographs at different times after tillage. The results showed that the surface crust-types as well as their tillage dependent dynamics greatly explain the decrease of hydraulic conductivity and sorptivity as the cumulative rainfall since tillage increases. The exponential decaying rates were found to be significantly greater for the soil harrowed along the slope (where the runoff crust-type covers more than 60% of the surface after 140 mm of rain) than across to the slope (where crusts are mainly of structural (60%) and erosion (40%) types). That makes ponding time smaller and runoff more important. Also it was shown that soil hydraulic properties after about 160 mm of rain were close to those of untilled plot not submitted to any rain. That indicates that the effects of tillage are short lived.

  10. Effects of long-term reduced tillage on weed infestation of pea (Pisum sativum L.

    Directory of Open Access Journals (Sweden)

    Andrzej Woźniak

    2014-09-01

    Full Text Available The study evaluated weed infestation of pea (Pisum sativum L. cultivated under conditions of conventional (CT, reduced (RT and herbicide tillage (HT. It demonstrated the highest weed density per m2 in plots with the herbicide (HT and reduced (RT systems and significantly lower weed infestation in plots cultivated in the conventional system (CT. In addition, more weeds occurred at the third leaf stage (13/14 in BBCH scale than at the pod development stage (73/74 BBCH of pea. The highest biomass was produced by weeds in the herbicide system (HT, a lower one – in the reduced system (RT, and the lowest one – in the conventional system (CT. The air-dry weight of weeds depended also on pea development stage. At the pod development stage (73/74 BBCH, the air-dry weight of weeds was significantly higher than at the third leaf stage (13/14 BBCH. The tillage system was also observed to influence the species composition of weeds. This trait was also affected by the period of weed infestation assessment. At the third leaf stage of pea (13/14 BBCH, there occurred 26 weed species, including 24 annual ones. The most abundant species included: Chenopodium album L., Stellaria media (L. Vill., Capsella bursa-pastoris (L. Med., Matricaria inodora L., Thlaspi arvense L., and Fallopia convolvulus (L. A. Löve. At the pod development stage (73/74 BBCH, the pea crop was colonized by 24 weed species, including 3 perennial ones. At this stage the predominant species included: Avena fatua L., Amaranthus retroflexus L., Papaver rhoeas L., Echinochloa crus-galli (L. P.B., Matricaria inodora L., and Galeopsis tetrahit L.

  11. [Effect of conservation tillage on weeds in a rotation system on the Loess Plateau of eastern Gansu, Northwest China].

    Science.gov (United States)

    Zhao, Yu-xin; Lu, Jiao-yun; Yang, Hui-min

    2015-04-01

    A field study was conducted to investigate the influences of no-tillage, stubble retention and crop type on weed density, species composition and community feature in a rotation system (winter wheat-common vetch-maize) established 12 years ago on the Loess Plateau of eastern Gansu. This study showed that the weed species composition, density and community feature varied with the change of crop phases. No-tillage practice increased the weed density at maize phase, while rotation with common vetch decreased the density in the no-tillage field. Stubble retention reduced the weed density under maize phase and the lowest density was observed in the no-tillage plus stubble retention field. No-tillage practice significantly increased the weed species diversity under winter wheat phase and decreased the diversity under common vetch phase. At maize phase, a greater species diversity index was observed in the no-tillage field. These results suggested that no-tillage practice and stubble retention possibly suppress specific weeds with the presence of some crops and crop rotation is a vital way to controlling weeds in a farming system.

  12. Soil infrastructure evolution and its effect on water transfer processes under contrasted tillage systems with preliminary results

    Science.gov (United States)

    Parvin, Nargish; Degré, Aurore; Chélin, Marie; Hiel, Marie-Pierre; Garré, Sarah; Bodson, Bernard

    2014-05-01

    The heterogeneity of soil structure and porosity are highly influenced by external factors like tillage systems and other land management approaches. The aim of this project is to investigate the effect of soil tillage along with residue management on the changing pattern of soil structure. This investigation will help to emphasize the different water flow dynamics especially the preferential flow processes through the soil that are influenced by the changes in structural distribution in the soil profile. Mostly the preferential flow of water is addressed by the apparent velocity through the soil but this study will focus on soil structure along with soil moisture dynamics at pedon scale or more specifically at aggregate scale. The experimentation has been started from June 2013 in the research field known as Solcouvert (objects: strip-till (ST) versus winter ploughing (WP)) and Solresidus (objects: no-till with organic matter restitution (NI) versus no-till without organic matter restitution (NO)). Soil profile description has been carried out in the four objects of land management. Soil sampling has been done in different depths of soil according to the soil profile description. Soil samples will be used for the measurement of water retention capacity (done), hydraulic conductivity and x-ray microtomography. The assessment of soil water retention curves with pressure plate technique show significantly (pnetworks in the field under four different trials. The soils from the different trials and also from different depths (0-15, 25-30 and 50-60 cm) were used for zone specific calibration of the sensors. All the experiments will be repeated twice a year. For the specific spatio-temporal comparison, the monitoring results from electrical resistance tomography will be available from the collaborated project of the same faculty.

  13. 营口市玉米机械化保护性耕作技术应用效果%Application Effect of Mechanized Corn Conservation Tillage Technology in Yingkou

    Institute of Scientific and Technical Information of China (English)

    高占文; 唐文举; 王殿忠; 董俊厚

    2014-01-01

    根据营口市实施保护性耕作的示范及实践,以传统耕作为对照,选取碎秆覆盖浅旋、碎秆覆盖少耕、整秆覆盖少耕3种保护性耕作模式进行对比试验,探讨保护性耕作对土壤温度、含水量、风蚀、肥力的影响。试验结果表明:保护性耕作技术能防治水土流失、培肥地力、提高降水利用率;整秆覆盖少耕模式适合在辽宁省大部分地区推广应用。%Comparative trial was conducted on the effect of conservation tillage in Yingkou with traditional tillage as the control, selecting 3 kinds of conservation tillage patterns, namely, the crushed stalk mulching shallow rotary tillage, crushed stalk mulching minimal tillage, and whole stalk mulching minimal tillage. The effects of conservation tillage on soil temperature, moisture, wind erosion, and soil fertility were explored. The test results showed that the conservation tillage technology can prevent soil erosion, increase soil fertility, improve the utilization rate of rainfall;and the whole stalk mulching minimal tillage mode is suitable for popularization and application in most areas of Liaoning province.

  14. Effect of conservation tillage on wheat and soil nutrient distribution and absorption%保护性耕作对土壤养分分布及冬小麦吸收与分配的影响

    Institute of Scientific and Technical Information of China (English)

    杨培培; 杨明欣; 董文旭; 陈素英; 胡春胜

    2011-01-01

    通过田间试验研究了华北平原山前平原区不同耕作方式下土壤氮、磷、钾等养分分布及冬小麦吸收与分配变化和对产量的影响.试验设深翻耕秸秆还田(MC)、秸秆还田旋耕(X)、秸秆粉碎免耕(NC)和整秸覆盖免耕(NW)4种冬小麦播前土壤耕作方式.试验结果表明,6年的不同耕作处理对土壤养分分布及冬小麦吸收与分配有显著影响.秸秆还田旋耕可显著提高土壤表层(0~5 cm)有机质、全氮以及碱解氨、速效磷、速效钾含量,但随土壤深度增加,提高效果呈逐渐下降趋势;20~30 cm土层土壤有机质、全氮和速效氮含量显著低于秸秆粉碎免耕处理,两种免耕模式(NC、NW)植株的全氮、全磷、全钾含量在苗期明显低于翻耕(MC)和旋耕(X)模式,在返青期差异最为显著.到拔节和扬花期,免耕(NC、NW)植株的全氮、全磷、全钾含量与翻耕(MC)和旋耕(X)之间的差异逐渐减少,并最终影响到籽粒养分的积累.%Conservation tillage technology improves soil environment, reduces wind and water erosion, and mitigates sandstorm. As a mode of agricultural technology, conservation tillage is drawing more and more global attention. Agricultural soils are increasingly managed through conservation or no-tillage. The objective of this study was to identify the effects of different conservation tillage patterns on N, P, K distribution in both soil and wheat, and also on their absorption of wheat in the North China Plain. The investigated tillage patterns included no-tillage with crushed straw (NC), no-tillage with entire straw (NW), traditional tillage with crushed straw (MC) and rotary tillage with crushed straw (X). The 6-year experiment showed significant differences in soil nutrient distribution and absorption, and also in wheat distribution among different tillage patterns. Rotary tillage significantly increased organic matter, total nitrogen and available N, P, K contents in the 0

  15. The effects of minimal tillage, contour cultivation and in-field vegetative barriers on soil erosion and phosphorus loss

    OpenAIRE

    2009-01-01

    Runoff, sediment, total phosphorus and total dissolved phosphorus losses in overland flow were measured for two years on unbounded plots cropped with wheat and oats.\\ud \\ud Half of the field was cultivated with minimum tillage (shallow tillage with a tine cultivator) and half was conventionally ploughed. Within each cultivation treatment there were different treatment areas (TAs). In the first year of the experiment, one TA was cultivated up and down the slope, one TA was cultivated on the co...

  16. The Effect of Tillage System and Crop Rotation on Soil Microbial Diversity and Composition in a Subtropical Acrisol

    Directory of Open Access Journals (Sweden)

    Eric W. Triplett

    2012-10-01

    Full Text Available Agricultural management alters physical and chemical soil properties, which directly affects microbial life strategies and community composition. The microbial community drives important nutrient cycling processes that can influence soil quality, cropping productivity and environmental sustainability. In this research, a long-term agricultural experiment in a subtropical Acrisol was studied in south Brazil. The plots at this site represent two tillage systems, two nitrogen fertilization regimes and three crop rotation systems. Using Illumina high-throughput sequencing of the 16S rRNA gene, the archaeal and bacterial composition was determined from phylum to species level in the different plot treatments. The relative abundance of these taxes was correlated with measured soil properties. The P, Mg, total organic carbon, total N and mineral N were significantly higher in the no-tillage system. The microbial diversity was higher in the no-tillage system at order, family, genus and species level. In addition, overall microbial composition changed significantly between conventional tillage and no-tillage systems. Anaerobic bacteria, such as clostridia, dominate in no-tilled soil as well as anaerobic methanogenic archaea, which were detected only in the no-tillage system. Microbial diversity was higher in plots in which only cereals (oat and maize were grown. Soil management influenced soil biodiversity on Acrisol by change of composition and abundance of individual species.

  17. Long-term tillage and crop rotation effects on residual nitrate in the crop root zone and nitrate accumulation in the intermediate vadose zone

    Science.gov (United States)

    Katupitiya, A.; Eisenhauer, D.E.; Ferguson, R.B.; Spalding, R.F.; Roeth, F.W.; Bobier, M.W.

    1997-01-01

    Tillage influences the physical and biological environment of soil. Rotation of crops with a legume affects the soil N status. A furrow irrigated site was investigated for long-term tillage and crop rotation effects on leaching of nitrate from the root zone and accumulation in the intermediate vadose zone (IVZ). The investigated tillage systems were disk-plant (DP), ridge-till (RT) and slot-plant (SP). These tillage treatments have been maintained on the Hastings silt loam (Udic Argiustoll) and Crete silt loam (Pachic Argiustoll) soils since 1976. Continuous corn (CC) and corn soybean (CS) rotations were the subtreatments. Since 1984, soybeans have been grown in CS plots in even calendar years. All tillage treatments received the same N rate. The N rate varied annually depending on the root zone residual N. Soybeans were not fertilized with N-fertilizer. Samples for residual nitrate in the root zone were taken in 8 of the 15 year study while the IVZ was only sampled at the end of the study. In seven of eight years, root zone residual soil nitrate-N levels were greater with DP than RT and SP. Residual nitrate-N amounts were similar in RT and SP in all years. Despite high residual nitrate-N with DP and the same N application rate, crop yields were higher in RT and SP except when DP had an extremely high root zone nitrate level. By applying the same N rates on all tillage treatments, DP may have been fertilized in excess of crop need. Higher residual nitrate-N in DP was most likely due to a combination of increased mineralization with tillage and lower yield compared to RT and SP. Because of higher nitrate availability with DP, the potential for nitrate leaching from the root zone was greater with DP as compared to the RT and SP tillage systems. Spring residual nitrate-N contents of DP were larger than RT and SP in both crop rotations. Ridge till and SP systems had greater nitrate-N with CS than CC rotations. Nitrate accumulation in IVZ at the upstream end of the

  18. [Effects of different tillage methods on photosynthetic characteristics, dry matter production and economic benefit of double cropping soybean].

    Science.gov (United States)

    Tang, Jiang-hua; Su, Li-li; Li, Ya-jie; Xu, Wen-xiu; Peng, Jiang-long

    2016-01-01

    In order to explore suitable mode of high yield cultivation of double cropping soybean after wheat under drip irrigation in northern Xinjiang, field trials were set in 2013-2014 to investigate physiological indices and agronomic traits of double cropping soybean under different tillage methods under drip irrigation. The results showed that leaf area index (LAI), chlorophyll content (SPAD), leaf net photosynthetic rate (Pn), transpiration rate (Tr) and stomatal conductance (g(s)) during the determination period under different tillage methods were in the order of tillage plus film covering (TP)> tillage (T)> rotary tillage (RT) > no-tillage (NT) , and the concentration of intercellular CO₂(Ci) was the opposite. LAI, SPAD, Pn, Tr, and g(s) of TP were higher than that with NT by 55.0%, 9.1%, 41.8%, 37.5% and 56.4%, respectively, and Ci was decreased by 22.1%. TP enhanced the photosynthetic efficiency of soybean and improved the ability of CO₂assimilation, consequently leading to the increase of soybean yield under TP compared to NT. The plant dry matter accumulation of TP treatment was improved greatly, with the pod number and seeds number per plant, 100-seed mass and yield of quadric sowing soybean being increased by 50.3%, 48.1%, 11.8% and 20.8% compared with that under NT, and the differences were significant. Therefore, the plastic film mulching combined with tillage under drip irrigation technology was suitable for double cropping soybean after wheat in northern Xinjiang under this experimental condition.

  19. Quantifying Temperature Effects on Fall Chinook Salmon

    Energy Technology Data Exchange (ETDEWEB)

    Jager, Yetta [ORNL

    2011-11-01

    The motivation for this study was to recommend relationships for use in a model of San Joaquin fall Chinook salmon. This report reviews literature pertaining to relationships between water temperature and fall Chinook salmon. The report is organized into three sections that deal with temperature effects on development and timing of freshwater life stages, temperature effects on incubation survival for eggs and alevin, and temperature effects on juvenile survival. Recommendations are made for modeling temperature influences for all three life stages.

  20. 免耕对粮食作物产量的影响%No-tillage effects on crop yield

    Institute of Scientific and Technical Information of China (English)

    彭文英; 彭美丽; 吴晓展

    2011-01-01

    Based on field investigation and fixed experimental observation from 2006 ~ 2007 in Beijing suburbs,comparison between the no-tillage and conventional tillage under crop growing and yield was made to analyse the problems during the implementation of no-tillage extension. The results reveal that compared with those in conventional tillage, the emergence and maturity of crops in no-tillage with mulching are later; and the number of plants can be 32% lower than conventional tillage during emergence and early seedling pulling of no-tillage winter wheat; Compared with conventional tillage, biomass of no-tillage winter wheat can be about 3% lower, but the underground root is measured 15% higher over the same period. No-tillage winter wheat can increase production by 2.2% in dry-spring years, but in rainy-spring years, production drops by 18.37%, and at most by 46.4%; No-tillage increases corm production by 2% ~ 18%. Prorooting the implementation of no-tillage also needs to strengthen scientific field management and increase govemment suppert and advocacy efforts to ensure the stability of no-tillage grain production and sustained implementation.%通过北京郊区大田调查和定点试验观测,对比研究了免耕覆盖与传统耕作两种措施下作物长势和产量差异,探讨了免耕覆盖技术推广实施中存在的问题.结果表明:与传统翻耕相比,免耕覆盖作物出苗和成熟更晚;免耕冬小麦出苗和生长初期,麦苗密度可低于传统翻耕32%;免耕覆盖玉米出苗和长势往往好于传统翻耕,出苗密度可高于传统翻耕约20%.与传统翻耕相比较,免耕覆盖冬小麦地上生物量可低3%左右,但同期测量地下根量却高15%;免耕冬小麦在春季干旱年份可增产2.2%,而在春季雨水较多的年份却减产18.37%,大田调查最高可造成减产46.4%;免耕覆盖玉米产量一般较高,可高出2%~18%.免耕技术推广实施还需要加强科学的田间管理,加大政府支持力度.

  1. Effects of tillage technologies and application of biopreparations on micromycetes in the rhizosphere and rhizoplane of spring wheat

    Science.gov (United States)

    Shirokikh, I. G.; Kozlova, L. M.; Shirokikh, A. A.; Popov, F. A.; Tovstik, E. V.

    2017-07-01

    The population density and structure of complexes of soil microscopic fungi in the rhizosphere and rhizoplane of spring wheat ( Triticum aestivum L.), plant damage by root rot and leaf diseases, and crop yield were determined in a stationary field experiment on a silty loamy soddy-podzolic soil (Albic Retisol (Loamic, Aric)) in dependence on the soil tillage technique: (a) moldboard plowing to 20-22 cm and (b) non-inversive tillage to 14-16 cm. The results were treated with the two-way ANOVA method. It was shown that the number of fungal propagules in the rhizosphere and rhizoplane of plants in the variant with non-inversive tillage was significantly smaller than that in the variant with plowing. Minimization of the impact on the soil during five years led to insignificant changes in the structure of micromycete complexes in the rhizosphere of wheat. The damage of the plants with root rot and leaf diseases upon non-inversive tillage did not increase in comparison with that upon plowing. Wheat yield in the variant with non-inversive tillage was insignificantly lower than that in the variant with moldboard plowing. The application of biopreparations based on the Streptomyces hygroscopicus A4 and Pseudomonas aureofaciens BS 1393 resulted in a significant decrease of plant damage with leaf rust.

  2. Cover plants and mineral nitrogen: effects on organic matter fractions in an oxisol under no-tillage in the cerrado

    Directory of Open Access Journals (Sweden)

    Isis Lima dos Santos

    2014-12-01

    Full Text Available Cover plants are essential for the sustainability of no-tillage systems in tropical regions. However, information on the effects of these plants and N fertilization on soil organic matter fractions is still scarce. This study evaluated the effect of cover crops with different chemical composition and of N topdressing on the labile and humified organic matter fractions of an Oxisol of the Cerrado (savanna-like vegetation. The study in a randomized complete block design was arranged in split-plots with three replications. Four cover species were tested in the plots and the presence or absence of N topdressing in the subplot. The following cover species were planted in succession to corn for eight years: Urochloa ruziziensis; Canavalia brasiliensis M. ex Benth; Cajanus cajan (L. Millsp; and Sorghum bicolor (L. Moench. In general, the cultivation of U. ruziziensis increased soil C levels, particularly of C in the humic acid and particulate organic C fractions, which are quality indicators of soil organic matter. The C in humic substances and mineral organic C accounted for the highest proportions of total organic C, demonstrating the strong interaction between organic matter, Fe and Al oxides and kaolinite, which are predominant in these weathered soils of the Cerrado.

  3. 保护性耕作对土壤综合特性的影响%Effects of Conservation Tillage on Characteristics of Soil

    Institute of Scientific and Technical Information of China (English)

    申丽霞; 王璞

    2011-01-01

    Conservation tillage is benefit for us to protect soil and water resources, conserve and increase their production potential and prevent degradation. It is significant in China due to the declining of cultivated land,the decreasing of soil fertility, and the expanding of soil erosion. Effects of conservation tillage on soil physical and biological property, fertility, moisture and temperature were analyzed. The roles of conservation tillage on water erosion and wind erosion control were also expressed. Study and application status and prospects of conservation tillage in China were summarized at last.%保护性耕作是一种有利于保护土壤、水等自然资源的生产潜力,提高土地生产力并防止土壤和水资源退化的一种土地利用方式.在中国耕地面积逐年减少,土壤肥力持续下降,水土流失严重的情况下发展保护性耕作具有重要意义.从土壤物理性状、土壤肥力状况、土壤生物学特性、土壤水分和温度几个方面分析了保护性耕作对土壤综合特性的影响,阐述了保护性耕作对减轻土壤水蚀、风蚀的作用,总结了目前中国保护性耕作研究与应用现状及发展前景.

  4. Effect of different pre-sowing tillage on quantity and quality of parsnip (Pastinaca sativa L. root yield in ridge cultivation

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    Mirosław Konopiński

    2012-12-01

    Full Text Available Parsnip is a very valuable vegetable due to its nutritional value and dietetic quality. It is moreover herbal raw material abundant in active substances. The yield quality of vegetables greatly depends on thorough pre-sowing soil tillage. The present study aimed at evaluating the influence of different presowing soil tillage (medium-deep ploughing, cultivating and plant growing methods, flat or ridge cultivation, on the yield of parsnip and some biometric traits of its roots. The field experiment was carried out in 1999, 2000 and 2002 on lessive soil with the granulometric composition corresponding to medium silty loam. The parsnip cultivar 'Półdługi Biały' was the experimental plant species. The cultivation of parsnip on ridges had a significant influence on increased total yield of roots and decreased yield of small roots, as compared to flat cultivation. A significant increase in unit weight of the root and its diameter in the top part was also recorded in the latter type of cultivation. Spring pre-sowing tillage had no significant effect on parsnip yields. An increasing trend was observed only for total and marketable root yield in the ploughed plots. When parsnip is grown on lessive soil (which has an unstable structure, plants cultivated on ridges after spring pre-sowing plough are the most beneficial treatment combination.

  5. Comparison of tillage treatments on greenhouse gas fluxes in winter wheat

    Science.gov (United States)

    Tillage is commonly used to control weeds and prepare fields for planting. Repeated tillage can result in soil drying, sudden bursts of mineralized carbon and nitrogen from soil organic matter, and alterations in soil microbial communities. The effects of tillage on winter wheat cropping systems an...

  6. Comparative Finite Element Analysis of the Effects of Tillage Tool Geometry on Soil Disturbance and Reaction Forces

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    Mohamed Ahmed Elbashir

    2014-04-01

    Full Text Available In this study a comparative finite element analysis was conducted to investigate the effects of tillage tool geometry on soil disturbance and reaction forces. A nonlinear three dimensional finite element model, using ANSYS software, was developed to study the soil cutting process by trapezoidal (T1 and rectangular (T2 flat tools that inclined to the horizontal at three rake angles (R1 = 30°, R2 = 60° and R3 = 90°, therefore a total of six treatments were considered in this analysis. The soil media was assumed as elastic-perfectly plastic material with Drucker-Prager’s model. Results of this study revealed that the maximum vertical soil displaced by T1 is greater than that of T2; hence T1 disturbed the soil better than T2 . Results also showed that a significant reduction in draft force was noticed when cutting the soil with T1 in comparison to T2 . Designing the tool in the form of T1 significantly reduces the surface area of the tool; thus conserving the engineering material.

  7. The Effects of Different Tillage Methods on Available Soil Potassium Measured by Various Extractors in a Soil with High Specific Surface Area

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    M. Hosseini

    2016-02-01

    Full Text Available Introduction: The effects of any tillage method on soil properties, depends on location (soil, water and air and the number of (years their implementation. Soil compaction reduces yield through increased soil mechanical resistance against root growth and lower water and nutrient use efficiency (Gamda et al. 18 & Ishagh et al 23. Soil surface and sub surface compaction both reduce yield due to limited root growth and plant potassium uptake (Doulan et al. 14. Sabt et al. (50 reported that in the study area, which the lands are mostly illite clay (high specific surface area with sufficient nitrogen, soil potassium is the most important limiting factor for the growth of wheat.Considering the point that loess soils in Golestan Province have a high specific surface area,they can provide potassium for plants to produce crop, but for a higher production, potassium fertilizers should be used. Previous studies indicated that production of wheat is limited due to potassium deficiency (4, 49, 54 and 57. In these soils with a high specific surface area, the speed of movement of potassium from the soil solution is low, and doing solimits wheat yield.In loess soils containing high illite and high specific surface area (eg, soilsin the series of Rahmat Abad of Gorgan, ammonium acetate measured potassium on exchange and solution surfaces, which is highly correlated with grain yield (54 . There is a high correlation between grain yield with overload of potassium and Na TPB extraction (57. The aim of this study was to absorb potassium (limiting factor for plant growth with different tillage systemsat different depths. International recommendations towards reducing the depth and intensity of tillage (from minimum tillage to no-tillage in order to reduce erosion and oxidation of organic substances plays an important role in determining the amount of greenhouse gases. If potassium absorption does not reduceafter reducing tillage intensity,low or no-tillage methods

  8. Artificial Neural Network Approach for Mapping Contrasting Tillage Practices

    Directory of Open Access Journals (Sweden)

    Terry Howell

    2010-02-01

    Full Text Available Tillage information is crucial for environmental modeling as it directly affects evapotranspiration, infiltration, runoff, carbon sequestration, and soil losses due to wind and water erosion from agricultural fields. However, collecting this information can be time consuming and costly. Remote sensing approaches are promising for rapid collection of tillage information on individual fields over large areas. Numerous regression-based models are available to derive tillage information from remote sensing data. However, these models require information about the complex nature of underlying watershed characteristics and processes. Unlike regression-based models, Artificial Neural Network (ANN provides an efficient alternative to map complex nonlinear relationships between an input and output datasets without requiring a detailed knowledge of underlying physical relationships. Limited or no information currently exist quantifying ability of ANN models to identify contrasting tillage practices from remote sensing data. In this study, a set of Landsat TM-based ANN models was developed to identify contrasting tillage practices in the Texas High Plains. Observed tillage data from Moore and Ochiltree Counties were used to develop and evaluate the models, respectively. The overall classification accuracy for the 15 models developed with the Moore County dataset varied from 74% to 91%. Statistical evaluation of these models against the Ochiltree County dataset produced results with an overall classification accuracy varied from 66% to 80%. The ANN models based on TM band 5 or indices of TM Band 5 may provide consistent and accurate tillage information when applied to the Texas High Plains.

  9. ASSESSMENT OF TILLAGE TRANSLOCATION AND TILLAGE EROSION ON LOESS SLOPE BY CONTOUR MOULDBOARD TILLAGE

    Directory of Open Access Journals (Sweden)

    Roman Rybicki

    2016-11-01

    Full Text Available This paper reports the results of tillage experiments that were set up to investigate the intensity of net soil displacement and the associated tillage erosivity for mouldboard tillage carried out in direction parallel to the contour lines (contour tillage. Tillage was performed with typical set of cultivation for an average farm on soil developed from loess located on a slope with 7.5 to 13.5% decrease. Aluminium cubes of 15 cm edge-length were used as tracers. The studies showed that average translocation of soil along the slope (perpendicular to tillage direction was 0,35 m and 0,28 m respectively for tillage with downslope and upslope direction of soil overturning. It means that each year about 2,89 Mg per hectare of soil is net displaced in downslope direction per plough operation. The studies indicated that contour moldboard tillage is also an important factor in relief and soil transformation of eroded areas.

  10. Impact of No-Tillage and Conventional Tillage Systems on Soil Microbial Communities

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    Reji P. Mathew

    2012-01-01

    Full Text Available Soil management practices influence soil physical and chemical characteristics and bring about changes in the soil microbial community structure and function. In this study, the effects of long-term conventional and no-tillage practices on microbial community structure, enzyme activities, and selected physicochemical properties were determined in a continuous corn system on a Decatur silt loam soil. The long-term no-tillage treatment resulted in higher soil carbon and nitrogen contents, viable microbial biomass, and phosphatase activities at the 0–5 cm depth than the conventional tillage treatment. Soil microbial community structure assessed using phospholipid fatty acid (PLFA analysis and automated ribosomal intergenic spacer analysis (ARISA varied by tillage practice and soil depth. The abundance of PLFAs indicative of fungi, bacteria, arbuscular mycorrhizal fungi, and actinobacteria was consistently higher in the no-till surface soil. Results of principal components analysis based on soil physicochemical and enzyme variables were in agreement with those based on PLFA and ARISA profiles. Soil organic carbon was positively correlated with most of the PLFA biomarkers. These results indicate that tillage practice and soil depth were two important factors affecting soil microbial community structure and activity, and conservation tillage practices improve both physicochemical and microbiological properties of soil.

  11. Tillage system affects microbiological properties of soil

    Science.gov (United States)

    Delgado, A.; de Santiago, A.; Avilés, M.; Perea, F.

    2012-04-01

    Soil tillage significantly affects organic carbon accumulation, microbial biomass, and subsequently enzymatic activity in surface soil. Microbial activity in soil is a crucial parameter contributing to soil functioning, and thus a basic quality factor for soil. Since enzymes remain soil after excretion by living or disintegrating cells, shifts in their activities reflect long-term fluctuations in microbial biomass. In order to study the effects of no-till on biochemical and microbiological properties in comparison to conventional tillage in a representative soil from South Spain, an experiment was conducted since 1982 on the experimental farm of the Institute of Agriculture and Fisheries Research of Andalusia (IFAPA) in Carmona, SW Spain (37o24'07''N, 5o35'10''W). The soil at the experimental site was a very fine, montomorillonitic, thermic Chromic Haploxerert (Soil Survey Staff, 2010). A randomized complete block design involving three replications and the following two tillage treatments was performed: (i) Conventional tillage, which involved mouldboard plowing to a depth of 50 cm in the summer (once every three years), followed by field cultivation to a depth of 15 cm before sowing; crop residues being burnt, (ii) No tillage, which involved controlling weeds before sowing by spraying glyphosate and sowing directly into the crop residue from the previous year by using a planter with double-disk openers. For all tillage treatments, the crop rotation (annual crops) consisted of winter wheat, sunflower, and legumes (pea, chickpea, or faba bean, depending on the year), which were grown under rainfed conditions. Enzymatic activities (ß-glucosidase, dehydrogenase, aryl-sulphatase, acid phosphatase, and urease), soil microbial biomass by total viable cells number by acridine orange direct count, the density of cultivable groups of bacteria and fungi by dilution plating on semi-selective media, the physiological profiles of the microbial communities by BiologR, and the

  12. Long-Term Effects of Rotational Tillage On Visual Evaluation of Soil Structure, Soil Quality and Crop Yield

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Heck, Richard; Deen, Bill

    year old long-term rotation and tillage treatment experiment on a Canadian silt loam soil. Measurements were carried out in the topsoil for three different rotations: R1 (C-C-C-C) continuous corn (Zea mays L.), R6. (C-C-O(RC), B(RC)) corn, corn, oats (Avena fatua L.) and spring barley (Hordeum vulgare...

  13. The Impact of Various Types of Tillage on the Soil Water Availability

    Directory of Open Access Journals (Sweden)

    BESNIK GJONGECAJ

    2014-07-01

    Full Text Available The present study is focused on the role that various ways of soil tillage may have on the increase of soil water availability to the plant roots. The research was carried out in Tirana, Albania, and the experiment was established in a vineyard field. The soil was cultivated in three different ways (three treatments: conventional (plowing plus surface cultivation, conservative (subsoiling plus surface cultivation, conservative (chisel plowing plus surface cultivation. In order to quantify the available soil water to plants, the pF-soil moisture curves were determined. The determined pF-soil moisture curves belong to two layers: 0-25 cm and 25-50 cm, taken into consideration for each treatment. The soil water content between the field capacity (FWC and the permanent wilting point (PWP was considered as potentially available to plant roots. The results showed clearly that the way the tillage was applied has a significant effect on soil water capacity potentially available to plant roots. Loosening the soil by breaking up the impermeable layers, the conservative tillage makes possible the increase of the amount of water held by soil particles in the range between FWC and PWP, in comparison with the conventional tillage. This increase of available soil water capacity is due to the soil loosening in deeper layers of soil profile as well, which leads to the situation where the plant roots can penetrate deeper and occupy more space, consequently, drawing more water to meet their needs. Within the conservative tillage versions, sub soiling seems to be more effective in the increase of available soil water capacity comparing with the chisel plowing. The study contributes, as well, to the determination of the pF-soil moisture curves in a way that is theoretically well based. The founded curves fit with the exponential form of functions and the coefficients of determinations, for each case under study, are significant in high probability levels.

  14. Factors Affecting Intercropping and Conservation Tillage Practices in Eeastern Ethiopia

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    S. Bauer

    2012-03-01

    Full Text Available In order to combat adverse effects of farmland degradation it is necessary for farmers to adopt sustainable land management and conservation strategies like intercropping and conservation tillage. However, efforts to adopt these strategies are very minimal in Ethiopia. In an attempt to address the objectives of examining factors affecting use of intercropping and conservation tillage practices, this study utilized plot- and household-level data collected from 211 farm households and employed a bivariate probit model for its analysis. The study revealed that intercropping and conservation tillage decisions are interdependent, and that they are also significantly affected by various factors. In addition, conservation tillage and intercropping practices as short- term interventions are found to augment the long-term interventions like terraces, diversion ditches, and tree plantations. The paper highlights important policy implications that are required to encourage intercropping and conservation tillage measures.

  15. Comparing effects of tillage treatments performed with animal traction on soil physical properties and soil electrical resistivity: preliminary experimental results

    Directory of Open Access Journals (Sweden)

    García-Tomillo Aitor

    2017-02-01

    Full Text Available Soil Compaction results from compressive forces applied to compressible soil by machinery wheels, combined with tillage operations. Draft animal‐pulled equipment may also cause soil compaction, but a huge gap exists on experimental data to adequately assess their impacts and, actually, animal traction is an option seen with increasing potential to contribute to sustainable agriculture, especially in mountain areas. This study was conducted to assess the impacts on soil compaction of tillage operations with motor tractor and draft animals. In a farm plot (Vale de Frades, NE Portugal treatments were applied in sub‐plots (30 m × 3 m, consisting in a two way tillage with tractor (T, a pair of cows (C and a pair of donkeys (D. Undisturbed soil samples (120 were taken before and after operations for bulk density (BD and saturated hydraulic conductivity (Ks. The relative changes in BD observed after tillage in the 0-0.05 m soil depth increased after operations in all treatments. The increase was higher in the tractor sub-plot (15% than in those where animal traction was used (8%. Before operation Ks class was rapid and fast in all samples, and after operation this value was reduced to 33% in T, whereas it reached 83% in C. Electrical Resistivity Tomography (ERT was useful as a tool to identify the alterations caused by tillage operations on soil physical status. These preliminary results confirm the potential of animal traction as an option for mountain agri‐environments, yet it requires much wider research to soundly ground its assets.

  16. Effect of Long-term Minimal and Zero Tillages on Rice and Wheat Yields,Soil Organic Matter and Bulk Density

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A long-term experiment of minimal and zero tillages was carried out on the sandy loam soil from 1985~1996. The results showed that the yields of minimal tillaged rice and wheat were similar to those by conventional tillage. Zero-tillaged wheat yield increased by 5.3% on average, while the zero-tillaged rice yield reduced by 2. 2%. The yields under long-term minimal and zero tillages showed no obvious temporal trend. After five years of the experiment, the soil organic matter contents were in steady state under different tillages, but its distributions in soil layers were different markedly and the richness in upper layer was observed under minimal and zero tillages, with the richness coefficients of 1. 1140 and 1. 1608, on 7-year average ,respectively. The bulk densities among different tillages were insignificantly different in soil layers of 0~7cm and 14~21cm. In the soil layer of 7~14cm,the bulk densities under conventional, minimal and zero tillages were 1.348,1.412 and 1. 410 g/cm3 respectively, minimal and zero tillages resulted in obvious increases in the bulk density.

  17. Effects of tillage practices on pea leaf weevil (Sitona lineatus L., Coleoptera: Curculionidae) biology and crop damage: a farm-scale study in the US Pacific Northwest.

    Science.gov (United States)

    Hanavan, R P; Bosque-Pérez, N A

    2012-12-01

    The pea leaf weevil, Sitona lineatus L., is periodically a significant pest of pea, Pisum sativum L., in the Palouse region of northern Idaho and eastern Washington, USA. Previous on-station research demonstrated significantly greater adult pea leaf weevil colonization, immature survival, adult emergence and plant damage in conventional-tillage compared to no-tillage plots of pea. In experiments conducted during the 2006 and 2007 growing seasons, aerial and ground adult pea leaf weevil colonization of large-scale commercial pea fields under different tillage regimes in northern Idaho and eastern Washington was examined for the first time. Initial pea leaf weevil feeding damage, immature weevil densities and subsequent adult emergence from the fields were also assessed. During both years, significantly more adult pea leaf weevils were captured in conventional-tillage than in no-tillage fields during the crop establishment period in May. No-tillage soils remained wet longer in the spring and could not be planted by growers until later than conventional-tillage fields. Pea planted under conventional-tillage emerged earlier and had significantly greater feeding damage by the pea leaf weevil than no-tillage pea. Significantly, greater immature pea leaf weevil densities and subsequent adult emergence were observed in conventional-tillage than in no-tillage pea fields. Delayed development of root nodules in the cooler, moister conditions of no-tillage pea fields likely resulted in escape from attack and injury during the critical growth stages that ultimately influence yield. Results indicate that large-scale commercial no-tillage pea fields are less suitable for colonization and survival of the pea leaf weevil and suffer less weevil damage than fields under conventional tillage.

  18. Quantification of tillage, plant cover, and cumulative rainfall effects on soil surface microrelief by statistical, geostatistical and fractal indices

    Directory of Open Access Journals (Sweden)

    J. Paz-Ferreiro

    2008-07-01

    Full Text Available Changes in soil surface microrelief with cumulative rainfall under different tillage systems and crop cover conditions were investigated in southern Brazil. Surface cover was none (fallow or the crop succession maize followed by oats. Tillage treatments were: 1 conventional tillage on bare soil (BS, 2 conventional tillage (CT, 3 minimum tillage (MT and 4 no tillage (NT under maize and oats. Measurements were taken with a manual relief meter on small rectangular grids of 0.234 and 0.156 m2, throughout growing season of maize and oats, respectively. Each data set consisted of 200 point height readings, the size of the smallest cells being 3×5 cm during maize and 2×5 cm during oats growth periods. Random Roughness (RR, Limiting Difference (LD, Limiting Slope (LS and two fractal parameters, fractal dimension (D and crossover length (l were estimated from the measured microtopographic data sets. Indices describing the vertical component of soil roughness such as RR, LD and l generally decreased with cumulative rain in the BS treatment, left fallow, and in the CT and MT treatments under maize and oats canopy. However, these indices were not substantially affected by cumulative rain in the NT treatment, whose surface was protected with previous crop residues. Roughness decay from initial values was larger in the BS treatment than in CT and MT treatments. Moreover, roughness decay generally tended to be faster under maize than under oats. The RR and LD indices decreased quadratically, while the l index decreased exponentially in the tilled, BS, CT and MT treatments. Crossover length was sensitive to differences in soil roughness conditions allowing a description of microrelief decay due to rainfall in the tilled treatments, although better correlations between

  19. No-tillage lessens soil CO2 emissions the most under arid and sandy soil conditions: results from a meta-analysis

    Science.gov (United States)

    Abdalla, Khatab; Chivenge, Pauline; Ciais, Philippe; Chaplot, Vincent

    2016-06-01

    The management of agroecosystems plays a crucial role in the global carbon cycle with soil tillage leading to known organic carbon redistributions within soils and changes in soil CO2 emissions. Yet, discrepancies exist on the impact of tillage on soil CO2 emissions and on the main soil and environmental controls. A meta-analysis was conducted using 46 peer-reviewed publications totaling 174 paired observations comparing CO2 emissions over entire seasons or years from tilled and untilled soils across different climates, crop types and soil conditions with the objective of quantifying tillage impact on CO2 emissions and assessing the main controls. On average, tilled soils emitted 21 % more CO2 than untilled soils, which corresponded to a significant difference at Ptillage had no impact on CO2 fluxes in clayey soils with high background SOCC (> 3 %). Finally, nitrogen fertilization and crop residue management had little effect on the CO2 responses of soils to no-tillage. These results suggest no-tillage is an effective mitigation measure of carbon dioxide losses from dry land soils. They emphasize the importance of including information on soil factors such as texture, aggregate stability and organic carbon content in global models of the carbon cycle.

  20. Use of physical properties to predict the effects of tillage practices on organic matter dynamics in three Illinois soils.

    Science.gov (United States)

    Yoo, Gayoung; Nissen, Todd M; Wander, Michelle M

    2006-01-01

    This work builds on a previous study of long-term tillage trials that found use of no-tillage (NT) practices increased soil organic carbon (SOC) sequestration at Monmouth, IL (silt loam soil) by increasing the soil's protective capacity, but did not alter SOC storage in DeKalb, IL (silty clay loam), where higher clay contents provided a protective capacity not affected by tillage. The least limiting water range (LLWR), a multi-factor index of structural quality, predicted observed soil CO2 efflux patterns. Here we consider whether LLWR can predict sequestration trends at a third site, Perry, IL (silt loam soil) where SOC content is lower and bulk density is higher than in previously considered sites, and determine whether pore size characteristics can help explain the influence use of NT practices has had on SOC sequestration at all three locations. At Perry, LLWR was again related with differences in specific soil organic carbon mineralization rates (RESPsp) (2000-2001). Reduced RESPsp rates explain increases in SOC storage under NT management observed only after 17 yr. Trends in RESPsp suggest use of NT practices only enhance physical protection of SOC where soil bulk density is relatively high (approximately 1.4 g cm(-3)). In those soils (Monmouth and Perry), use of NT management reduced the volume of small macropores (15-150 microm) thought to be important for microbial activity. Physical properties appear to determine whether or not use of NT practices will enhance C storage by increasing physical protection of SOC. By refining the functions used to compute the LLWR and our understanding of the interactions between management, pore structure, and SOC mineralization, we should be able to predict the influence of tillage practices on SOC sequestration.

  1. Research Progress on Effect of Potato No-tillage Cultivation on Soil Character%马铃薯免耕栽培对土壤性状影响的研究进展

    Institute of Scientific and Technical Information of China (English)

    韦剑锋; 韦冬萍; 熊建文; 梁和

    2012-01-01

    近年来,世界栽培新模式的马铃薯免耕栽培技术在中国的迅速发展与推广应用,马铃薯免耕栽培方面的研究越来越多,其中马铃薯免耕栽培对土壤性状影响的研究方兴未艾.为此,参考相关文献资料,归纳了国内马铃薯免耕栽培对土壤的物理性状、化学性状、主要养分、杂草种子、微生物及酶活性等方面的影响,分析了马铃薯免耕栽培对土壤性状影响的研究状况,提出了有待于进一步研究的问题.%In recent years, the no-tillage cultivation technique of potato was developing and appled rapidly in China. So there have been more and more researches on the potato no-tillage cultivation, which included the effects of potato no-tillage cultivation on soil property. The writer summarized the effects of potato no-tillage cultivation on soil character, which included physical and chemical properties, nutrient status, weed seeds, microflora and enzyme activities of soil, etc. Moreover, the research status in soil effects of potato no-tillage cultivation was analyzed. Finally, the further research topics in soil effects of potato no-tillage cultivation were also proposed.

  2. Effects of Zero Tillage (No-Till) Conservation Agriculture on soil physical and biological properties and their contributions to sustainability

    Science.gov (United States)

    Landers, John N.; Rass, Gerard; de Freitas, Pedro L.; Basch, Gottlieb; González Sanchez, Emilio J.; Tabaglio, Vincenzo; Kassan, Amir; Derpsch, Rolf; Friedrich, Theodor; Giupponi, Luca

    2013-04-01

    Not cultivating soil, rotating crops over the years, and leaving crop residues on the surface in the practice of zero tillage/conservation agriculture (ZT/CA) reverses the historically accelerating degradation of soil organic matter (SOM) and soil structure, while increasing soil biological activity by a factor of 2 to 4. The results of this are many: (a) not cultivating reduces soil compaction, leaving old root holes to facilitate internal drainage, averts the pulverization of soil aggregates and formation of pans, reduces draft power for planting and gives shelter, winter food and nesting sites for fauna, (b) crop residues on the surface practically eliminate wind and water erosion, reduce soil moisture loss through the mulch effect, slow spring warm-up (possibly offset by a lower specific heat demand with less water retention in surface soil) and act as a reserve of organically-compounded nutrients (as they decompose to humus), (c) more SOM means higher available water and nutrient retention, higher biological activity year round (enhancing biological controls), higher levels of water-stable aggregates and a positive carbon sink in incremental SOM. The positive impacts for society are: (i) more and cheaper food, (ii) reduced flood and drought-induced famine risks, (iii) a positive carbon sink in SOM and possible reductions in NO2 emissions, (iv) cleaner water and greater aquifer recharge due to reduced runoff, (v) cleaner air through effective elimination of dust as a product of cultivation (vi) less water pollution and greater aquifer recharge from reduced rainfall runoff, (vii) farm diesel consumption halved, (viii) reduced demand for (tropical) de-forestation, by permitting crop expansion on steeper lands, (ix) increased wildlife populations (skylarks, plovers, partridge and peccaries) and (x) an improved conservation mindset in farmers. It is notable that, in spite of successful practitioners in all European countries, mainstream adoption is still to come

  3. Maize (Zea mays L.) and Cotton (Gossypium hirsutum L.) Straw Decomposition in Soil: Effect of Straw Placement, Mineral Nitrogen and Tillage

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    With the present understanding that decomposing straw may not only affect soil properties, but pos-sibly greenhouse gas emissions as well, focus among environmental researchers has gradually expanded toinclude understanding of decomposition rate and stability of straw of different plants in different soils underdifferent management conditions. Against such a background, a short-term (60 days) greenhouse simulationexperiment was carried out to study the effects of straw placement, external mineral N source and tillageon straw decomposition of maize and cotton in two contrasting soils, a red soil (Ferrasol) and a black soil(Acrisol). The treatments included straw addition only (T1); straw addition + mineral N (T2); and strawaddition + tillage (T3). Straw was either buried in the soil or placed on the surface. Sampling was doneevery 15 days. Placement, addition of external mineral N sources (urea, 46% N), straw type, soil type andexposure duration (15, 30, 45 and 60 days) affected straw decomposition. Decomposition was more in buriedstraw than in surface-placed straw at all sampling dates in red soil. The addition of an external N sourcesignificantly increased decomposition. The study could not, however, fully account for the effect of tillageon straw decomposition because of the limited effect of our tillage method due to the artificial barrier tomechanical interference supplied by the mesh bags.

  4. Soil organic carbon sequestration potential of conservation vs. conventional tillage

    Science.gov (United States)

    Meurer, Katharina H. E.; Ghafoor, Abdul; Haddaway, Neal R.; Bolinder, Martin A.; Kätterer, Thomas

    2017-04-01

    Soil tillage has been associated with many negative impacts on soil quality, especially a reduction in soil organic carbon (SOC). The benefits of no tillage (NT) on topsoil SOC concentrations have been demonstrated in several reviews, but the effect of reduced tillage (RT) compared to conventional tillage (CT) that usually involves soil inversion through moldboard ploughing is still unclear. Moreover, the effect of tillage on total SOC stocks including deeper layers is still a matter of considerable debate, because the assessment depends on many factors such as depth and method of measurement, cropping systems, soil type, climatic conditions, and length of the experiments used for the analysis. From a recently published systematic map database consisting of 735 long-term field experiments (≥ 10 years) within the boreal and temperate climate zones (Haddaway et al. 2015; Environmental Evidence 4:23), we selected all tillage studies (about 80) reporting SOC concentrations along with dry soil bulk density and conducted a systematic review. SOC stocks were calculated considering both fixed soil depths and by using the concept of equivalent soil mass. A meta-analysis was used to determine the influence of environmental, management, and soil-related factors regarding their prediction potential on SOC stock changes between the tillage categories NT, RT, and CT. C concentrations and stocks to a certain depth were generally highest under NT, intermediate under RT, and lowest under CT. However, this effect was mainly limited to the first 15 cm and disappeared or was even reversed in deeper layers, especially when adjusting soil depth according to the equivalent soil mineral mass. Our study highlights the impact of tillage-induced changes in soil bulk density between treatments and shows that neglecting the principles of equivalent soil mass leads to overestimation of SOC stocks for by conservation tillage practices.

  5. Nitrogen fertilization (15NH4NO3 of palisadegrass and residual effect on subsequent no-tillage corn

    Directory of Open Access Journals (Sweden)

    Emerson Borghi

    2014-10-01

    Full Text Available Nitrogen is required in large amounts by plants and their dinamics in corn and perennial forages intercropped is little known. This study analyzed the efficiency of nitrogen fertilization (15NH4NO3 applied after corn grain harvest to palisadegrass (Brachiaria brizantha cv. Marandu in intercrops sown at two times, as well as the N residual effect on the subsequent corn crop. The field experiment was performed in Botucatu, São Paulo State, in southeastern Brazil, on a structured Alfisol under no-tillage. The experiment was arranged in a randomized block design in a split plot scheme with four replications. The main plots consisted of two intercropping systems (corn and palisadegrass sown together and palisadegrass sown later, at corn top-dressing fertilization. The subplots consisted of four N rates (0, 30, 60, and 120 kg ha-1 N. The subplots contained microplots, in which enriched ammonium nitrate (15NH4NO3 was applied at the same rates. The time of intercrop sowing affected forage dry matter production, the amount of fertilizer-derived N in and the N use efficiency by the forage plants. Nitrogen applied in autumn to palisadegrass intercropped with corn, planted either at corn sowing or at N top-dressing fertilization, increased the forage yield up to a rate of 60 kg ha-1. The amount of fertilizer-derived N by the forage plants and the fertilizer use efficiency by palisadegrass were highest 160 days after fertilization for both intercrop sowing times, regardless of N rates. Residual N did not affect the N nutrition of corn plants grown in succession to palisadegrass, but increased grain yield at rates of 60 and 120 kg ha-1 N, when corn was grown on palisadegrass straw from the intercrop installed at corn fertilization (top-dressing. Our results indicated that the earlier intercropping allowed higher forage dry matter production. On the other hand, the later intercrop allowed a higher corn grain yield in succession to N-fertilized palisadegrass.

  6. [Numerical evaluation of soil quality under different conservation tillage patterns].

    Science.gov (United States)

    Wu, Yu-Hong; Tian, Xiao-Hong; Chi, Wen-Bo; Nan, Xiong-Xiong; Yan, Xiao-Li; Zhu, Rui-Xiang; Tong, Yan-An

    2010-06-01

    A 9-year field experiment was conducted on the Guanzhong Plain of Shaanxi Province to study the effects of subsoiling, rotary tillage, straw return, no-till seeding, and traditional tillage on the soil physical and chemical properties and the grain yield in a winter wheat-summer maize rotation system, and a comprehensive evaluation was made on the soil quality under these tillage patterns by the method of principal components analysis (PCA). Comparing with traditional tillage, all the conservation tillage patterns improved soil fertility quality and soil physical properties. Under conservative tillage, the activities of soil urease and alkaline phosphatase increased significantly, soil quality index increased by 19.8%-44.0%, and the grain yield of winter wheat and summer maize (expect that under no till seeding with straw covering) increased by 13%-28% and 3%-12%, respectively. Subsoiling every other year, straw-chopping combined with rotary tillage, and straw-mulching combined with subsoiling not only increased crop yield, but also improved soil quality. Based on the economic and ecological benefits, the practices of subsoiling and straw return should be promoted.

  7. Soil Tillage Systems and Wheat Yield under Climate Change Scenarios

    OpenAIRE

    Pieranna Servadio; Simone Bergonzoli; Claudio Beni

    2016-01-01

    In this study, the effects of three different main preparatory tillage operations: ploughing at 0.4 m (P40) and 0.20 m (P20) depth and harrowing at 0.20 m depth (MT) were investigated. The tillage operations were carried out at two different times, as the soil water content increased over time from rainfall: (low, 58% (LH) and high, 80% (HH) of field capacity). Results obtained from the soil monitoring carried out before and after tillage showed high values of soil strength in terms of Penetr...

  8. Tillage and cover cropping effects on soil properties and crop production in Illinois

    Science.gov (United States)

    Cover crops (CCs) have been heralded for their potential to improve soil properties, retain nutrients in the field, and increase subsequent crop yields yet support for these claims within the state of Illinois remains limited. We assessed the effects of integrating five sets of CCs into a corn-soybe...

  9. Tillage system and time post-liquid dairy manure: Effects on runoff, sediment and nutrients losses

    Science.gov (United States)

    Liquid manure applied in agricultural lands improves soil quality. However, incorrect management of manure may cause environmental problems due to sediments and nutrients losses associated to runoff. The aims of this work were to: (i) evaluate the time effect of post-liquid dairy manure (LDM) applic...

  10. Comparison of tillage treatments on greenhouse gas and soil carbon and nitrogen cycling in established winter wheat production

    Science.gov (United States)

    Tillage is commonly used to control weeds and prepare fields for planting. Repeated tillage can result in soil drying, sudden bursts of mineralized carbon and nitrogen from soil organic matter, and alterations in soil microbial communities. The effects of tillage on winter wheat cropping systems an...

  11. Efeitos da calagem em semedura direta de milho Effect of lime application on no-tillage corn

    Directory of Open Access Journals (Sweden)

    Josinei Antonio Tissi

    2004-12-01

    Full Text Available As conseqüências das alterações químicas do solo, decorrentes da calagem na superfície, sobre o crescimento radicular e a nutrição do milho cultivado em semeadura direta são pouco conhecidas. Com o objetivo de avaliar os efeitos da aplicação superficial de calcário nos atributos químicos do solo, no crescimento de raízes e na nutrição da planta de milho, e seus reflexos sobre o rendimento de grãos, foi realizado um experimento em Latossolo Vermelho distrófico textura muito argilosa, manejado há seis anos em semeadura direta, em Tibagi (PR. Os tratamentos, aplicados em parcelas de 44,8 m², foram dispostos em blocos completos ao acaso com quatro repetições e constaram da aplicação de quatro doses de calcário dolomítico na superfície: 0, 1, 2 e 3 t.ha-1 (PRNT = 100%. As doses de calcário (27% de CaO, 20% de MgO e 85% de PRNT foram baseadas no requerimento de 1/3, 2/3 e na quantidade total calculada para elevar a saturação por bases do solo, na camada de 0-20 cm, a 70%. A calagem, após 22 meses, aumentou o pH em CaCl2 0,01 mol.L-1, os teores de Ca e Mg trocáveis e a saturação por bases, e reduziu os teores de H + Al e de Al trocável, na camada superficial do solo (0-10 cm, e ocasionou aumento de Ca trocável e redução de Al trocável no subsolo (20-40 cm. A aplicação superficial de doses de calcário não alterou o comprimento e a distribuição relativa de raízes de milho até a profundidade de 40 cm, reduziu o raio médio de raízes e aumentou a absorção de P, Ca, Mg e S pelas plantas, sem causar reflexos sobre o rendimento de grãos. Os teores de Cu, Fe, Mn e Zn no solo e no tecido foliar do milho, bem como sua absorção pelas plantas, não foram alterados com a aplicação de calcário na superfície.The effects of superficial lime application on chemical soil attributes under no-tillage systems and its influence on root growth and mineral nutrition in maize crops have not been thoroughly investigated

  12. Effect of simplified tillage and mineral fertilization on weed infestation of potato growing on loess soil

    Directory of Open Access Journals (Sweden)

    Karol Bujak

    2012-12-01

    Full Text Available In the paper effect of limitation of postharvest measure to single cultivating or disking of soil and mineral fertilization level on number, air-dry matter and botanical composition of weeds in the potato-field is presented. Simplifield postharvest measure was increasing insignificantly and more intensive fertilization was limiting the weed infestation of potato-field. Decteasing of weeds number increasing fertilization was ststistically significant. Dominating species of weeds in the potato-field were Capsella bursa-pastoris, Poa annua, Viola arvensis, Chenopodium album, Elymus repens i Equisetum arvense.

  13. Soil tillage and windbreak effects on millet and cowpea: I. Wind speed, evaporation, and wind erosion

    Energy Technology Data Exchange (ETDEWEB)

    Banzhaf, J.; Leihner, D.E.; Buerkert, A. (Univ. of Hohenheim, Stuttgart (Germany)); Serafini, P.G. (Univ. of Arkansas, Fayetteville (United States))

    Deforestation, overgrazing, and declining soil regeneration periods have resulted in increased wind erosion problems in dry areas of the West African Sahel, but little is known about the bio-physical factors involved. This research was conducted to determine the effects of ridging and four different windbreak spacings on wind erosion, potential evaporation, and soil water reserves. A field trial was conducted from 1985 to 1987 on 12 ha of a Psammentic Paleustalf in Southern Niger. Millet, Pennisetum glaucum (L.), and cowpea, Vigna unguiculata (L.) Walp., were seeded in strips on flat and ridged soil. Windbreaks of savannah vegetation were spaced at 6, 20, 40, and 90 m. The effects of ridging on wind speed, evaporation, and wind erosion were small and mostly non-significant. However, average wind speed at 0.3 m above ground in the center of cowpea and millet strips was significantly reduced from 2.8 to 2.1 m s[sup [minus]1] as windbreak distances narrowed from 90 to 6 m. As a consequence, potential evaporation declined by 15% and the amount of windblown soil particles by 50% in ridged and by 70% in flat treatments. Despite reduced potential evaporation, average subsoil water reserves were 14 mm smaller in the 6- than in the 20-m windbreak spacing indicating excessive water extraction by the windbreak vegetation. Thus, establishing windbreaks with natural savannah vegetation may require a careful consideration of the agronomic benefits and costs to competing crops. 21 refs., 5 figs.

  14. Effects of land clearing techniques and tillage systems on runoff and soil erosion in a tropical rain forest in Nigeria.

    Science.gov (United States)

    Ehigiator, O A; Anyata, B U

    2011-11-01

    This work reports runoff and soil loss from each of 14 sub-watersheds in a secondary rain forest in south-western Nigeria. The impact of methods of land clearing and post-clearing management on runoff and soil erosion under the secondary forest is evaluated. These data were acquired eighteen years after the deforestation of primary vegetation during the ' West bank' project of the International Institute for Tropical Agriculture (IITA). These data are presented separately for each season; however, statistical analyses for replicates were not conducted due to differences in their past management. Soil erosion was affected by land clearing and tillage methods. The maximum soil erosion was observed on sub-watersheds that were mechanically cleared with tree-pusher/root-rake attachments and tilled conventionally. A high rate of erosion was observed even when graded-channel terraces were constructed to minimize soil erosion. In general there was much less soil erosion on manually cleared than on mechanically cleared sub-watersheds (2.5 t ha(-1) yr(-1) versus 13.8 t ha(-1) yr(-1)) and from the application of no-tillage methods than from conventionally plowed areas (6.5 t ha(-1) yr(-1) versus 12.1 t ha(-1) yr(-1)). The data indicate that tillage methods and appropriate management of soils and crops play an important role in soil and water conservation and in decreasing the rate of decline of soil quality.

  15. Effects of different regimes of fertilization on soil organic matter under conventional tillage

    Directory of Open Access Journals (Sweden)

    Zhibin Guo

    2014-07-01

    Full Text Available To explore the effects of different fertilization regimes on soil organic matter (SOM sequestration in a winter-soybean/corn rotation, a long-term field experiment was conducted in Anhui, China, from 1982 to 2011. There were six treatments, as follows: (1 no fertilizer input (CK; (2 mineral fertilizers input (NPK; (3 mineral fertilizers + 3,750 kg ha-1 wheat straw (WS/2-NPK; (4 mineral fertilizers + 7,500 kg ha-1 wheat straw (WS-NPK; (5 mineral fertilizers + 15,000 kg ha-1 composted farmyard manure (CNPK; and (6 mineral fertilizers + 30,000 kg ha-1 composted farmyard manure (DNPK. Mineral fertilizer applications combined with organic amendments improved soil physical properties. For the WS/2-NPK, WS-NPK, CNPK and DNPK treatments, the soil bulk density decreased more than 10%, while the air porosity and field water content increased more than 90% and 15%, compared with the values at the start of the experiment in 1982. Our results indicate that about two decades are needed for SOM to reach its saturation point in all treatments. The SOM sequestration rate was related to the fertilization regime. The average SOM sequestration rate in 1982-2005 was 0.27 g kg-1 yr-1 with NPK, 0.45 g kg-1 yr-1 with WS/2-NPK, 0.56 g kg-1 yr-1 with WS-NPK, 0.60 g kg-1 yr-1 with CNPK and 1.02 g kg-1 yr-1 with DNPK. Therefore, both the quantity and the quality of the organic amendment determine the SOM sequestration rate and SOM saturation level.

  16. Effect of water management, tillage options and phosphorus status on arsenic uptake in rice.

    Science.gov (United States)

    Talukder, A S M H M; Meisner, C A; Sarkar, M A R; Islam, M S

    2011-05-01

    High arsenic (As) concentrations in soil may lead to elevated concentrations of arsenic in agricultural products. Field experiments were conducted to examine the effects of water management (WM) and Phosphorus (P) rates on As uptake, rice growth, yield and yield attributes of winter (boro) and monsoon (aman) rice in an As contaminated soil-water at Gobindagonj, Gaibandha, Bangladesh in 2004 and 2005. Significantly, the highest average grain yields (6.88±0.07 t ha(-1) in boro 6.38±0.06 t ha(-1) in aman) were recorded in permanent raised bed (PRB; aerobic WM: Eh=+360 mV) plus 100% P amendment. There was a 12% yield increase over conventional till on flat (CTF; anaerobic WM: Eh=-56 mV) at the same P level. In boro, the As content in grain and As content in straw were about 3 and 6 times higher in CTF compared to PRB, respectively. The highest total As content (0.646±0.01 ppm in grain and 10.93±0.19 ppm in straw) was recorded under CTF, and the lowest total As content (0.247±0.01 and 1.554±0.09 ppm in grain and straw, respectively) was recorded under PRB (aerobic WM). The results suggest that grain and straw As are closely associated in boro rice. The furrow irrigation approach of the PRB treatments consistently reduced irrigation input by 29-31% for boro and 27-30% for aman rice relative to CTF treatments in 2004 and 2005, respectively, thus reducing the amount of As added to the soil from the As-contaminated irrigation water. Yearly, 30% less As was deposited to the soil compared to CTF system through irrigation water during boro season. High As concentrations in grain and straw in rice grown using CTF in the farmers' field, and the fact that using PRB reduced grain As concentrations to value less than half of the proposed food hygiene standard.

  17. The effect of conservation tillage on the structural characteristics of Fluvo-aquic soil%保护性耕作对潮土结构特性的影响

    Institute of Scientific and Technical Information of China (English)

    赵红; 吕贻忠

    2009-01-01

    研究不同保护性耕作措施对潮土结构特性的影响,探求不同秸秆还田方式下土壤结构的变化规律.以河北省石家庄市栾城县长期定位试验为研究基础,采用了传统翻耕、翻耕秸秆还田、旋耕秸秆还田、免耕覆盖还田、免耕立秆还田和免耕粉碎还田6种处理,分别对不同耕层的土壤容重、有机碳含量、团聚体及有机无机复合体进行了测定,对比分析了不同保护性耕作对潮土结构特性的影响.结果表明:免耕覆盖还田的土壤容重值最低;干筛情况下,免耕秸秆覆盖还田的MWD值显著高于其它处理30.4%~47.4%,而湿筛情况下,免耕立秆还田与粉碎还田MWD值高于其它处理;立秆还田的土壤分散系数最低,而粉碎还田的分散系数比其它处理高20.48%~330.93%;翻耕处理的原土复合量、原土复合度分别高于免耕处理10.82%~21.62%、8.97%~20.97%.不同秸秆还田方式对土壤结构稳定性的影响有很大差异:覆盖还田能改善田间土壤结构;立秆还田能提高微团聚体的稳定性;粉碎还田通过增加土壤有机碳含量而增加水稳性大团聚体的含量.%The effect of different conservation tillage measurement on structural characteristics of Fluvo-aquic soil were studied, and the variation law of soil structure under different ways of straw returning were searched. This study is based on long field experi-ments of Luancheng country of Hebei province Shijiazhuang city, six treatments of tillage systems were utilized: conventional tillage、tillage with straw returning、rotary tillage with straw returning, no tillage with mulch, no tillage with standing stubble and no tillage with crush returning, soil bulk density, soil organic carbon content, aggregate and organo-mineral complexes were measured. The results showed: the lowest soil bulk density value is no tillage with mulch; the MWD value of no tillage with mulch significantly higher than other treatments 30

  18. Impact of reduced tillage on the greenhouse gas balance - a meta-analysis

    Science.gov (United States)

    Don, Axel; Jantz, Marc

    2013-04-01

    Minimum tillage and no-tillage has been acknowledged as human induced measure for climate mitigation due to its potential to sequester additional soil carbon. However, there is increasing evidence that reduced tillage affects the vertical distribution of carbon in the soil profile, but hardy increases soil carbon stocks. Additionally, reduced tillage may increase the N2O emissions that would counterbalance the positive effects of soil carbon sequestration. Here we present a new meta-analysis on the full field scale effect of reduced tillage and no-tillage for the temperate zone including soil organic carbon, N2O and diesel derived fossil fuel emissions for field management. This analysis was performed using strict selection criteria and included data from more than 115 sites on soil carbon stock changes and from more than 30 sites with measured N2O fluxes on paired fields with conventional and reduced tillage. Soil organic carbon stocks did hardly increase (mean ±standard deviation: 2 ±11 Mg C ha-1) under no tillage as compared to moldboard ploughing. At 38% of all sites decreasing soil carbon stocks were detected under no-tillage as compared to conventional tillage. On the other hand, N2O emissions increased by around 40% on no-tillage fields with large deviations between sites. Thus, the total greenhouse gas balance turned out to be more negative for most no-tillage fields as compared to conventional tillage fields. The large observed scatter and deviations between sites and their controlling factors are discussed.

  19. Efeito prolongado de sistemas de preparo do solo com e sem cultivo de soqueira de cana crua em algumas propriedades físicas do solo Long-term effect of soil tillage systems with and without tillage of green-cane stump in soil physical properties

    Directory of Open Access Journals (Sweden)

    Fábio Camilotti

    2005-04-01

    Full Text Available Este trabalho foi conduzido em Latossolo Vermelho distrófico típico, sob cultivo de cana crua, com o objetivo de avaliar o efeito prolongado de sistemas de preparo do solo, com e sem cultivo da soqueira, e épocas de amostragem sobre algumas propriedades físicas do solo. O delineamento experimental foi o de blocos ao acaso, em esquema de parcelas subsubdivididas, sendo os tratamentos principais quatro sistemas de preparo do solo: (i controle da soqueira com duas gradagens, subsolagem e mais uma gradagem de nivelamento; (ii controle da soqueira com herbicida e uma subsolagem; (iii controle da soqueira com herbicida; (iv controle da soqueira com herbicida, aração com arado de aivecas e uma gradagem de nivelamento. Os tratamentos secundários foram: com cultivo e sem cultivo da soqueira. Os tratamentos ternários foram as épocas de avaliação: dois dias antes e após a quarta colheita da cultura. A porosidade total, macroporosidade, microporosidade e densidade do solo foram avaliadas, além do perfilhamento e da produtividade da cultura. Após quatro sucessivas colheitas de cana crua, houve redução da macroporosidade com aumento da microporosidade nas camadas abaixo de 10 cm e aumento da densidade do solo entre 20 e 50 cm. A densidade do solo não foi alterada de modo consistente em função de todos os tratamentos testados. O cultivo da soqueira favoreceu o aumento da macroporosidade com decréscimo na microporosidade, e o efeito inverso foi observado após a colheita. Os sistemas de preparo do solo e de cultivo da soqueira não afetaram o perfilhamento e a produtividade da cultura.This work was carried out at the field conditions in a Typic Haplustox soil with green-cane crop with the objective to evaluate long-term effect of soil tillage systems with and without tillage of stump in soil physical properties. A complete randomized blocks in split-split-plots arrangement of treatments were used. The principal treatments were four soil

  20. Quantifying nonadditive selection caused by indirect ecological effects.

    Science.gov (United States)

    TerHorst, Casey P; Lau, Jennifer A; Cooper, Idelle A; Keller, Kane R; La Rosa, Raffica J; Royer, Anne M; Schultheis, Elizabeth H; Suwa, Tomomi; Conner, Jeffrey K

    2015-09-01

    In natural biological communities, species interact with many other species. Multiple species interactions can lead to indirect ecological effects that have important fitness consequences and can cause nonadditive patterns of natural selection. Given that indirect ecological effects are common in nature, nonadditive selection may also be quite common. As a result, quantifying nonadditive selection resulting from indirect ecological effects may be critical for understanding adaptation in natural communities composed of many interacting species. We describe how to quantify the relative strength of nonadditive selection resulting from indirect ecological effects compared to the strength of pairwise selection. We develop a clear method for testing for nonadditive selection caused by indirect ecological effects and consider how it might affect adaptation in multispecies communities. We use two case studies to illustrate how our method can be applied to empirical data sets. Our results suggest that nonadditive selection caused by indirect ecological effects may be common in nature. Our hope is that trait-based approaches, combined with multifactorial experiments, will result in more estimates of nonadditive selection that reveal the relative importance of indirect ecological effects for evolution in a community context.

  1. Monitoring of Conservation Tillage and Tillage Intensity by Ground and Satellite Imagery

    Directory of Open Access Journals (Sweden)

    M.A Rostami

    2014-09-01

    Full Text Available Local information about tillage intensity and ground residue coverage is useful for policies in agricultural extension, tillage implement design and upgrading management methods. The current methods for assessing crop residue coverage and tillage intensity such as residue weighing methods, line-transect and photo comparison methods are tedious and time-consuming. The present study was devoted to investigate accurate methods for monitoring residue management and tillage practices. The satellite imagery technique was used as a rapid and spatially explicit method for delineating crop residue coverage and as an estimator of conservation tillage adoption and intensity. The potential of multispectral high-spatial resolution WorldView-2 local data was evaluated using the total of eleven satellite spectral indices and Linear Spectral Unmixing Analysis (LSUA. The total of ninety locations was selected for this study and for each location the residue coverage was measured by the image processing method and recorded as ground control. The output of indices and LSUA method were individually correlated to the control and the relevant R2 was calculated. Results indicated that crop residue cover was related to IPVI, RVI1, RVI2 and GNDVI spectral indices and satisfactory correlations were established (0.74 - 0.81. The crop residue coverage estimated from the LSUA approach was found to be correlated with the ground residue data (0.75. Two effective indices named as Infrared Percentage Vegetation Index (IPVI and Ratio Vegetation Index (RVI with maximum R2 were considered for classification of tillage intensity. Results indicated that the classification accuracy with IPVI and RVI indices in different conditions varied from 78-100 percent and therefore in good agreement with ground measurement, observations and field records.

  2. Factors Influencing Observed Tillage Impacts on Herbicide Transport

    Science.gov (United States)

    Pappas, E. A.; Huang, C.; Smith, D. R.

    2009-04-01

    The widespread use and potential human health effects of the herbicides atrazine and glyphosate have generated interest in establishing how no-tillage impacts loading of these herbicides to runoff water in comparison to other tillage practices. In this study, potentially confounding factos such as time in tillage practice and type and distribution of residue cover, are weighed against inherent tillage impacts to soil structure in terms of relative effects on herbicide transport with runoff water. In this study, two small watersheds (one in no-till (NT) and one rotational till (RT)) were monitored during the first three years since conversion of the RT watershed from NT. In addition, rainfall simulation was applied to plots within each watershed during the first, third, and fifth years since the conversion. Runoff atrazine and glyphosate losses from RT areas were compared to losses from NT areas as a ratio of RT:NT. Results indicate a trend of increasing RT:NT value with time in tillage. Watershed monitoring indicated greater herbicide loading to runoff water from the NT watershed than the RT watershed during the first year since RT conversion, but this relationship reversed by the third year since conversion to RT. In addition, rainfall simulations were performed on small boxes of NT or RT soil having varying types and levels of residue cover in an attempt to isolate residue cover effects from true tillage effects.

  3. Influence of tillage on adult and immature pea leaf weevil (Coleoptera: Curculionidae) densities in pea.

    Science.gov (United States)

    Hanavan, Ryan P; Bosque-Pérez, Nilsa A; Schotzko, Dennis J; Eigenbrode, Sanford D

    2010-06-01

    The pea leaf weevil, Sitona lineatus (L.) (Coleoptera: Curculionidae), has been a major pest of pea, Pisum sativum L., in eastern Washington and northern Idaho since its introduction to the region in the early 1970s. Eggs are deposited in the spring on the soil surface and first instars hatch and move to pea root nodules, where larvae feed before they pupate and adults emerge in mid- to late summer. No-tillage practices are known to reduce pea leaf weevil colonization in pea, but the effects of tillage on larval densities and subsequent adult emergence have not been examined. During 2005, 2006, and 2007, we compared densities of colonizing adult and immature pea leaf weevils on pea plots grown using conventional tillage and no-tillage. In 2005 and 2006, emergence of adult pea leaf weevil was monitored in the same plots. Densities of colonizing adult and immature pea leaf weevil were significantly higher in conventional tillage plots. Larvae in conventional tillage were further along in development than larvae in no-tillage plots during June and July. Densities of emerging adult pea leaf weevil were significantly greater from conventional tillage than no-tillage plots. Based on densities of colonizing and subsequent emerging adults, survival of weevils from egg through adult was greater in conventional tillage plots. Soils under no-tillage are cooler, resulting in later emergence of the pea crop and delayed root nodule development, possibly affecting the ability of first-instar pea leaf weevil to locate host plant roots. Our results indicate no-tillage fields are less suitable for pea leaf weevil colonization and survival than conventional tillage fields.

  4. Water erosion and soil water infiltration in different stages of corn development and tillage systems

    Directory of Open Access Journals (Sweden)

    Daniel F. de Carvalho

    2015-11-01

    Full Text Available ABSTRACTThis study evaluated soil and water losses, soil water infiltration and infiltration rate models in soil tillage systems and corn (Zea mays, L. development stages under simulated rainfall. The treatments were: cultivation along contour lines, cultivation down the slope and exposed soil. Soil losses and infiltration in each treatment were quantified for rains applied using a portable simulator, at 0, 30, 60 and 75 days after planting. Infiltration rates were estimated using the models of Kostiakov-Lewis, Horton and Philip. Based on the obtained results, the combination of effects between soil tillage system and corn development stages reduces soil and water losses. The contour tillage system promoted improvements in soil physical properties, favoring the reduction of erosion in 59.7% (water loss and 86.6% (soil loss at 75 days after planting, and the increase in the stable infiltration rate in 223.3%, compared with the exposed soil. Associated to soil cover, contour cultivation reduces soil and water losses, and the former is more influenced by management. Horton model is the most adequate to represent soil water infiltration rate under the evaluated conditions.

  5. MEAN INFILTRATION SPEED IN A VERTISOL UNDER DIFFERENT TILLAGE SYSTEMS

    Directory of Open Access Journals (Sweden)

    Juan José Martínez Villanueva

    2015-03-01

    Full Text Available Soil compaction is regarded as the most serious environmental problem caused by conventional agriculture. Few studies are concerned with the assessment of soil compaction using infiltration speed, specifically in the Vertisol soil characteristic of the main maize producing area of the Toluca-Atlacomulco Valley in central Mexico. The aim of this research was to examine the effect on infiltration speed and penetration resistance of a Vertisol soil when compacted by wheeled agricultural traffic in three different types of tillage systems: zero, minimal and conventional. Penetration resistance was measured on the wheel track with a portable digital penetrometer, and the mean infiltration speed was determined according to the double cylinder infiltrometer method. The pressure exerted by the number of wheeled traffic passes increased Vertisol soil compaction at 30 cm depth. Even though the benefits of zero tillage were similar to those showed by minimum tillage during the experimental period, minimum tillage reported the highest infiltration speed.

  6. Gross mineralization of nitrogen in fertile soils. Effects of the tillage system and soil depths; Mineralizacao bruta do nitrogenio em solos de alta fertilidade. Efeito do manejo e a profundidade de amostragem

    Energy Technology Data Exchange (ETDEWEB)

    Videla, C.; Echeverria, H.; Studdert, G. [Universidad Nacional de Mar del Plata (UNMdP), Balcarce (Argentina). Facultad Ciencias Agrarias; Trivelin, P.C.; Bendassolli, J.A. [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil)

    2002-07-01

    A greenhouse experiment was carried out with the aim of determining the effect of different tillage systems and soil depths on gross mineralization rates (TMB). The studied soil was a Typic Argiudoll Petrocalcic Paleudoll complex, under: conventional tillage for 23 yr. (PC treatment); no tillage for 6 yr. (PD treatment), and pasture for 4 yr. (P treatment) and 0-10 and 10-20 sampling depths. TMB were estimated through {sup 15} N dilution technique, by addition of labelled (NH{sub 4}){sub 2}SO{sub 4} (10% {sup 15} N at. exc.) at days 0, 7, 21 and 35. Twenty-four and 72 h after each addition, N inorganic content and {sup 15} N enrichment of inorganic were determined on 2M KCl extracts in order to estimate the TMB. At 0-10 cm depth, TMB increase until day 21 and decreased afterwards. There were no significant differences between tillage treatments. At 10-20 cm soil depth PC and PD TMB were constant during the whole analysed period. P treatment had a quadratic adjust, with negative linear component. P TMB was lower than PC and PD until day 21 but afterwards it was significantly higher. These results suggest the presence in the pasture of an organic matter fraction, which mineralizes lately but with a high rate. (author)

  7. 耕作方式对农田土壤微生物功能多样性的影响%Effects of Different Tillage Modes on Metabolic Functional Diversity of Soil Microbial Community

    Institute of Scientific and Technical Information of China (English)

    姬艳艳; 张贵龙; 张瑞; 刘玉升; 杨殿林; 王彩灵

    2013-01-01

    通过种植前对土壤进行不同耕作处理试验,探讨不同耕作方式对土壤微生物群落代谢功能多样性的影响.采用Biolog-ECO微平板检测法,研究了撂荒、翻耕、免耕和旋耕4种不同耕作方式下土壤微生物碳源代谢的多样性变化特征.结果表明:在168 h培养期内,撂荒和免耕处理下AWCD值明显高于翻耕和旋耕处理;免耕条件下微生物功能多样性指数、优势度指数和丰富度指数与撂荒条件相似,而进行翻耕和旋耕后,三指标均显著下降.土壤微生物群落主成分分析和聚类分析结果显示,免耕条件下,土壤微生物具有接近于撂荒处理的碳源代谢模式和代谢能力,翻耕和旋耕则差异较大.分析试验结果,不同耕作方式对土壤微生物群落代谢和功能多样性产生较显著影响,免耕对其具有较好的保护作用.%The effects of different tillage modes on soil microbe functional diversity were evaluated in this paper through different tillage test on soil before planting. The soil microbial metabolism diversity in four tillage modes including abandoned, tilled, no-tillage and rotary were examined by the method of Biolog ECO-micro plate culture. The result showed that within 168 h of culture, the average well color development (AWCD) was obviously higher in no-tillage than in the tilled mode. The functional diversity, dominance and richness index of soil microbes in no-tillage and abandoned were incredibly similar, when they fell significantly in tilled and rotary treatments. The result of PCA and cluster analysis demonstrated that the carbon source metabolic pattern and ability of the soil microbes in no-tillage was similar to that in abandoned, while it had a significant alteration in tilled and rotary. Different tillage modes could affect the metabolic and functional diversity of soil microbial communities significantly; no-tillage had better protective effect than other tillage modes.

  8. Effects of no-tillage plus inter-planting and remaining straw on the field on cropland eco-environment and wheat growth%免耕套种与秸秆还田对农田生态环境及小麦生长的影响

    Institute of Scientific and Technical Information of China (English)

    刘世平; 张洪程; 戴其根; 霍中洋; 许轲; 阮慧芳

    2005-01-01

    The studies showed that under no-tillage plus inter-planting rice and wheat, the height nf rice stubble remained on the field significantly affected light transmission rate, with an optimal height of 20 - 30 cm. No-tillage and straw-remaining decreased soil temperature at noon in sunny days, but slightly increased it in the morning and evening, led to a less diurnal difference of soil temperature. The average diurnal .soil temperature under no-tillage was higher in cloudy but lower in sunny days. Under no-tillage and straw-remaining, both the bulk density and the penetration resistance of topsoil increased, but no apparent adverse effect of them was observed on wheat growth. Under no-tillage, soil water content was higher under drought condition, and soil permeability after irrigation was better, which was propitious to the wheat growth. Straw-remaining significantly inhibited weeds, but led to the decrease of basic seedlings and enhanced the damage of freezing. Under no tillage plus inter-planting,the individuals of effective ears decreased, while the kilo-grain weight increased. The grain yield was slightly but not significantly low under no-tillage plus inter-planting.

  9. Two years monitoring of soil N_{2}O emissions on durum wheat in a Mediterranean area: the effect of tillage intensity and N-fertilizer rate.

    Science.gov (United States)

    Volpi, Iride; Bosco, Simona; Triana, Federico; Di Nasso, Nicoletta Nassi o.; Laville, Patricia; Virgili, Giorgio; Bonari, Enrico

    2016-04-01

    Evaluating the magnitude and the key factors affecting N2O emissions from agriculture has a scientific and practical relevance, in fact emissions from agricultural and natural soils account for 56-70% of all global N2O sources (Syakila and Kroeze, 2011). Moreover, the necessity to increase the food production rate minimizing greenhouse gas emissions require a deeper understanding of the effect of the agricultural practices on direct soil emissions. Therefore, the aim of this work is to assess the effect of tillage intensity and nitrogen rate on soil N2O emissions on durum wheat. A two years monitoring campaign was carried out using a high-sensibility transportable instrument developed within the LIFE+ "Improved flux Prototypes for N2O emission from Agriculture" IPNOA project (Bosco et al., 2015; Laville et al., 2015). The project aims at improving the measurement technique of N2O flux directly in field using the flow-through non-steady state chamber technique. The monitoring campaign on durum wheat lasted for two growing seasons and two fallow periods (2013-14 and 2014-15). Treatment on the main plot was tillage intensity with two levels, ploughing and minimum tillage, and three different nitrogen rates were distributed to the subplots (N0: 0 kg ha-1, N1: 110 kg ha-1, N2: 170 kg ha-1). Ancillary measurements concerned meteorological data, soil temperature and moisture, NO3-, NH4+ soil concentration. Main results of the two years highlighted N rate as the main driver for both N2O daily flux and cumulative emissions during the growing season, while in the fallow period treatments did not affect the emission magnitude. Tillage intensity was not a key factor for N2O emissions. N2O emissions were significantly different in the two years. In particular, cumulative emissions of 2013-14 were about five times higher than in 2014-15, respectively on average 2885±260 g N-N2O ha-1 and 534±53 g N-N2O ha-1 for a similar monitoring period of about 300 days. Differences could be

  10. Efectos de tratamientos de labranza sobre la resistencia a la penetración de un Andisol Effects of tillage treatments on penetration resistance on an andisol

    Directory of Open Access Journals (Sweden)

    Jiménez Javier

    1992-06-01

    Full Text Available Se evaluó el efecto sobre la resistencia a la penetración de cuatro implementos de labranza (arado de cinceles, arado de discos, rastrillo californiano y arado rotatorio en un Andisol (Andic-Eutropept serie Tibaitatá. Para las medidas, se utilizó un penetrómetro registrador digital. Los resultados mostraron que los tratamientos que involucraron arado rotatorio y arado de discos y rastrillo fueron los que causaron el mayor grado de aflojamiento del suelo. Sin embargo, dichos tratamientos fueron los más susceptibles a la compactación por pase de llantas. No se pudo concluir lo planteado por la literatura de que el fondo de surco de arado es una zona de alto
    riesgo de compactación del subsuelo. La resistencia a la penetración resultó un buen indicador para evaluar efectos físicos sobre el suelo causarlos por implementos de labranza y él tránsito de maquinaria.The effects on Cone Penetration Resistance caused by four tillage implements (chisel plow, disk plough, disk harrow and rotatiller were assesed on an Andisol, using a digital penetrometer. The results showed the treatments using rota-tiller and those using disk plough and disk harrow caused
    the maximun soilloosening. However those treatments were the most sensitive to compaction due to the traffic of tractor
    wheels. This work did not present conclusive evidence that bottom of furrow made by disk plough is a place of high risk for subsoil cornpactlon. Cone penetration resistance looks like a good index to assess changes in physical properties of the soil caused by tillage operations and machinery traffic.

  11. A multifractal approach to characterize cumulative rainfall and tillage effects on soil surface micro-topography and to predict depression storage

    Directory of Open Access Journals (Sweden)

    E. Vidal Vázquez

    2010-10-01

    discriminate data sets with similar values for the vertical component of roughness. Conversely, both, rough and smooth soil surfaces, with high and low roughness values, respectively, can display similar levels of spectral complexity. Although in most of the studied cases trend removal produces increasing homogeneity in the spatial configuration of height readings, spectral complexity of individual data sets may increase or decrease, when slope or slope plus tillage tool marks are filtered. Increased cumulative rainfall had significant effects on various parameters from the generalized dimension, Dq, and singularity spectrum, f(α. Overall, micro-topography decay by rainfall was reflected on a shift of the singularity spectra, f(α from the left side (q>>0 to the right side (q<<0 and also on a shift of the generalized dimension spectra from the right side (q>>0 to the left side (q<<0. The use of an exponential model of vertical roughness indices, RR, and multifractal parameters accounting for the spatial configuration such as D1 or D5 improved estimation of water stored in surface depressions.

  12. A multifractal approach to characterize cumulative rainfall and tillage effects on soil surface micro-topography and to predict depression storage

    Directory of Open Access Journals (Sweden)

    E. Vidal Vázquez

    2010-03-01

    sets with similar values for the vertical component of roughness. Both, rough and smooth soil surfaces, with high and low roughness values, respectively, can display similar levels of spectral complexity. Although in most of the studied cases trend removal produces increasing homogeneity in the spatial configuration of height readings, spectral complexity of individual data sets may increase or decrease, when slope or slope plus tillage tool marks are filtered. Increased cumulative rainfall had significant effects on various parameters from the generalized dimension, Dq, and singularity spectrum, f(α. Overall, micro-topography decay by rainfall produced was reflected on a shift of the singularity spectra, f(α from the left side (q>>0 to the right side (q<<0 and also on a shift of the generalized dimension spectra from the right side (q>>0 to the left side (q<<0. The use of an exponential model of vertical roughness indices, RR, and multifractal parameters accounting for the spatial configuration such as D1, D5, and D10 improved estimation of water stored in surface depressions.

  13. Effects of Tillage Managements in Wheat-maize Whole Season on the Stem and Ear Traits in Summer Maize%小麦-夏玉米周年耕作措施对夏玉米茎秆和穗部性状的影响

    Institute of Scientific and Technical Information of China (English)

    刘淑梅; 张洪生; 韩伟; 姜雯; 张倩

    2012-01-01

    为了探索山东省半湿润易旱区夏玉米高产稳产适宜耕作措施,将冬小麦和夏玉米两季耕作技术作为一体,设置了10种周年耕作措施,比较分析不同耕作措施对夏玉米茎秆、穗部性状及产量的影响.耕作试验(一周年)结果表明,不同耕作措施对玉米株高和穗位高没有显著性影响,而对茎粗和穗高系数影响显著,其中对照即常规耕作方式(小麦旋耕+玉米直播+秸秆不还田)茎秆最细,穗高系数最高,而A1B11(小麦旋耕+玉米旋耕+秸秆还田)、A2B21(小麦免耕+玉米直播+秸秆还田)、A3B31(小麦深松+玉米深松+秸秆还田)和A4B41(小麦深耕+玉米深耕+秸秆还田)耕作处理间茎秆粗度均显著高于其他处理.与对照相比,各耕作措施显著增加了玉米穗行粒数和百粒重,秃顶长度减小,籽粒产量和生物量均显著增加,其中A1B11(小麦旋耕+玉米旋耕+秸秆还田)耕作处理籽粒产量最高,比对照高35.83%.%In order to explore the most suitable tillage to reach high and stable yield in summer maize in sub-humid and drought areas in Shandong province, with ten different tillage treatments during wheat-maize whole season, the effects of tillage managements on the stem and ear characteristics and grain yield in summer maize were studied. The results showed that, effect of different tillage managements on plant height and ear height was not significant, but indeed affected stem diameter and coefficient of ear height significantly, among all tillage managements, stem was the thinnest and coefficient of ear height was the highest in CK. (rotary tillage at wheat season + direct seeding maize + no straw returning), and the stem diameter was the highest in treatments A1B11, A2B21, A3B31 and A4B41, I.e. Rotary tillage at wheat season + rotary tillage at maize season + straw returning, no-tillage at wheat season + no-tillage at maize season + straw returning, subsoiling tillage at wheat season + subsoiling

  14. Share of anthropophytes in the crop sequence: winter wheat – maize – spring wheat depending on tillage system

    Directory of Open Access Journals (Sweden)

    Tomasz R. Sekutowski

    2014-07-01

    Full Text Available An experiment, conducted over the period 2008–2010, evaluated the effect of tillage system on the occurrence and species composition of anthropophytes in winter wheat, maize and spring wheat. Regardless of crop plant and tillage system, anthropophytes (73.9%, represented by archaeophytes and kenophytes, were the main component of the flora in the crops studied, whereas apophytes accounted for the remaining 26.1%. Most archaeophytes (13 species were found in the spring wheat crop under no-tillage, while their lowest number (6 species occurred in the spring wheat crop under conventional tillage. The only kenophyte, Conyza canadensis, was found to occur in the spring wheat and maize crops in the no-tillage system. The following taxa were dominant species among archeophytes: Geranium pusillum, Anthemis arvensis, and Viola arvensis (regardless of tillage system and crop plant, Anthemis arvensis (in spring wheat – conventional tillage, Echinochloa crus-galli and Setaria glauca (in maize – reduced tillage and no-tillage, Chenopodium album (in maize – no-tillage as well as Apera spica-venti, Anthemis arvensis and Papaver rhoeas (in winter wheat – no-tillage.

  15. Quantifying the effect of baryon physics on weak lensing tomography

    CERN Document Server

    Semboloni, Elisabetta; Schaye, Joop; van Daalen, Marcel P; McCarthy, Ian J

    2011-01-01

    We use matter power spectra from cosmological hydrodynamic simulations to quantify the effect of baryon physics on the weak gravitational lensing shear signal. The simulations consider a number of processes, such as radiative cooling, star formation, supernovae and feedback from active galactic nuclei (AGN). Van Daalen et al. (2011) used the same simulations to show that baryon physics, in particular the strong feedback that is required to solve the overcooling problem, modifies the matter power spectrum on scales relevant for cosmological weak lensing studies. As a result, the use of power spectra from dark matter simulations can lead to significant biases in the inferred cosmological parameters. We show that the typical biases are much larger than the precision with which future missions aim to constrain the dark energy equation of state, w_0. For instance, the simulation with AGN feedback, which reproduces X-ray and optical properties of groups of galaxies, gives rise to a ~40% bias in w_0. We demonstrate ...

  16. EFFECTS OF DIFFERENT SOIL TILLAGE SYSTEMS ON YIELD OF MAIZE, WINTER WHEAT AND SOYBEAN ON ALBIC LUVISOL IN NORTH-WEST SLAVONIA

    Directory of Open Access Journals (Sweden)

    Silvio KOŠUTIĆ

    2006-05-01

    Full Text Available The paper presents comparison of three soil tillage systems in maize, winter wheat and soybean growing on anthropogenic Albic Luvisol in north-west Slavonia, Croatia, during 1996-1999. Tillage systems and implements were: 1. conventional system (CT-plough, disc-harrow and combined implement, 2. conservation system (RT-chisel plough and multitiller, 3. no-till system (NT. The aim of testing was comparison of different tillage systems energy requirement and its influence on yield. Results indicate that conventional tillage (CT system was the greatest energy consumer with 1813.10 MJ ha-1. Comparing to conventional tillage (CT system, conservation (RT system with chisel plough and multitiller spent 1133.14 MJ ha-1or 37.5 % less, while no-till (NT system required even 85.1 % less energy or 270.13 MJ ha-1. In the first season the greatest yield of maize, 7.78 Mg ha-1, achieved conventional tillage (CT system while next to it was conservation (RT system with 7.77 Mg ha-1. No-till (NT system achieved 7.56 Mg ha-1. Second season the greatest yield of winter wheat, 5.89 Mg ha-1, achieved conservation tillage (RT system. Next to it was conventional (CT system with 5.75 Mg ha-1, while no-till (NT achieved 5.73 Mg ha-1. Third season the greatest yield of soybean, 2.71 t ha-1, achieved conservation tillage (RT system again, while next to it was conventional (CT system with 2.64 Mg ha-1. No-till (NT achieved 2.61 Mg ha-1.

  17. Soil respiration in a long-term tillage treatment experiment

    Science.gov (United States)

    Gelybó, Györgyi; Birkás, Márta; Dencsö, Márton; Horel, Ágota; Kása, Ilona; Tóth, Eszter

    2016-04-01

    Regular soil CO2 efflux measurements have been carried out at Józsefmajor longterm tillage experimental site in 2014 and 2015 with static chamber technique in no-till and ploughing plots in seven spatial replicates. The trial was established in 2002 on a loamy chernozem soil at the experimental site of the Szent István University nearby the city Hatvan, northern Hungary. At the site sunflower (Helianthus A.) and wheat (Triticum A.) was grown in 2014 and 2015, respectively. Ancillary measurements carried out at the site included weather parameters, soil water content, soil temperature. The aim of the investigation was to detect the effect of soil disturbance and soil tillage treatments on soil CO2 emission in agricultural ecosystems. Soil respiration measurements were carried out every week during the vegetation period and campaign measurements were performed scheduled to tillage application. In this latter case, measurements were carried out 1, 2, 3, 4, 6, 12, 18, 24, 48, 72, 96, 120 hours and 7 days after tillage operation. Results showed that during the vegetation season in the majority of measurement occasions emission was higher in the no-till plots. These differences; however were not found to be statistically significant. Due to the short term effect of tillage treatment, emissions increased following tillage treatment in the ploughed plots. Soil water content was also examined as main driver of soil CO2 fluxes. Soil water content sharply decreases in the surface layer (5-10 cm depth) after tillage treatment indicating a fast drying due to soil disturbance. This effect slowly attenuated and eventually extincted in approx. two weeks. CO2 emission measurements were associated with high uncertainties as a result of the measurement technique. Our further aim is to reduce this uncertainty using independent measurement techniques on the field.

  18. Monoculture Maize (Zea mays L. Cropped Under Conventional Tillage, No-tillage and N Fertilization: (II Fumonisin Incidence on Kernels

    Directory of Open Access Journals (Sweden)

    Carolina Gavazzi

    2009-09-01

    Full Text Available Planting maize under no-tillage is an increasing farming practice for sustainable agriculture and sound environmental management. Although several studies on yield of no-till maize have been done, there is few information about the effect of tillage on fumonisin contamination. The present study was done to determine the effect of notillage and conventional tillage with two rates of nitrogen on fumonisin content in kernels of continuous maize. Average grain contamination with fumonisins B1 and B2 over the years 2004-06 was not significantly different, with mean values of 1682, 1984 and 2504 μg kg-1, respectively. Fumonisin B1 was the most abundant toxin found in the samples. No-tillage significantly affected the incidence of fumonisins during the first year of the trial, in which fumonisin content was significantly higher with no-till (2008 μg kg-1 compared with conventional tillage (1355 μg kg-1. However, no-tillage did not significantly affect the incidence of fumonisins in the second and third years of the study. Fumonisin content at the rate of 300 kg N ha-1 was not statistically different compared to that obtained without N fertilization. The interaction between the soil management system and the rate of applied nitrogen was only evident in the second year. Our results indicate that fumonisin contamination was affected by no-tillage only in the first year. Nitrogen fertilization had no significant effect on fumonisin content in any year. The weather conditions during susceptible stages of maize development have probably overridden the effect of nitrogen fertilization.

  19. Nitrogen application in the maize, under no tillage system: effects in the soil physical quality and agronomics characteristics

    Directory of Open Access Journals (Sweden)

    Flávia Carvalho Silva

    2014-05-01

    Full Text Available This research was developed in the experimental area of ESALQ-USP, city of Piracicaba , state of Sao Paulo, in a soil of sandy-clay texture and aimed to evaluate the soil physical quality and maize agronomic characteristics with maize crop under different N doses and different tillage systems. The experimental design consisted of randomized blocks with four replicates. Treatments consisted of three nitrogen doses (N (60, 120, and 180 kg ha-1 and a control. The ammonium sulfate fertilizer was applied at 30 kg ha-1 N during seeding, and the rest was applied as sidedressing when the plants had between six and eight leaves. Were determined the bulk density, microporosity, macroporosity and total porosity of soil, at depths of 0.05, 0.15, 0.25, 0.35 m, and the maize components yield. The soil physical properties tend to change over time and N levels, especially with regard to soil macroporosity and microporosity, conditioned by the structural change of the soil.

  20. Monitoring Two Small Catchments to Evaluate Effects of No-Tillage Agricultural Management in São Paulo State, Brazil

    Science.gov (United States)

    Figueiredo, R. D. O.; Gonçalves, A. O.; Melo, A. D. S.; de Bona, F. D.; Hernani, L. C.

    2015-12-01

    In recent years, declines in water and soil quality have been observed in areas of Brazil where no-till agriculture had been previously implemented. Poor soil management associated with the absence of public policies has caused soil erosion, because many farmers are moving back from no-till to traditional cultivation for faster economic gains. A research project - SoloVivo Project - leaded by Embrapa (Brazilian Agricultural Research Corporation) in partnership with Itaipu Binacional aims to develop and validate, in a participatory way, tools to evaluate the technical performance of soil and water management at the rural properties that practice no-till agriculture. In this context we have selected two paired small (communication for data collection) linked to: a high intensity tipping bucket rain gage; a reflectometer to monitor soil volumetric water content, bulk electric conductivity and temperature; a radar water level sensor; a turbidity sensor; and an electric conductivity-temperature probe. We expect that stream flow and sediment generation, besides water quality (measured by conductivity) may serve as indicators of the benefits of no-tillage agriculture done more or less well. The results of this study will be used to stimulate discussions at workshops with the farmers who participate in a rural producers association in the region. In addition this and other results can be used to help the Brazilian National Water Agency (ANA) decide about applying no-till agricultural management systems in its programs of payment for environmental services.

  1. Turbulent characteristics of a semiarid atmospheric surface layer from cup anemometers – effects of soil tillage treatment (Northern Spain

    Directory of Open Access Journals (Sweden)

    S. Yahaya

    Full Text Available This paper deals with the characteristics of turbulent flow over two agricultural plots with various tillage treatments in a fallow, semiarid area (Central Aragon, Spain. The main dynamic characteristics of the Atmospheric Surface Layer (ASL measured over the experimental site (friction velocity, roughness length, etc., and energy budget, have been presented previously (Frangi and Richard, 2000. The current study is based on experimental measurements performed with cup anemometers located in the vicinity of the ground at 5 different levels (from 0.25 to 4 m and sampled at 1 Hz. It reveals that the horizontal wind variance, the Eulerian integral scales, the frequency range of turbulence and the turbulent kinetic energy dissipation rate are affected by the surface roughness. In the vicinity of the ground surface, the horizontal wind variance logarithmically increases with height, directly in relation to the friction velocity and the roughness length scale. It was found that the time integral scale (and subsequently the length integral scale increased with the surface roughness and decreased with the anemometer height. These variations imply some shifts in the meteorological spectral gap and some variations of the spectral peak length scale. The turbulent energy dissipation rate, affected by the soil roughness, shows a z-less stratification behaviour under stable conditions. In addition to the characterization of the studied ASL, this paper intends to show which turbulence characteristics, and under what conditions, are accessible through the cup anemometer.

    Key words. Meteorology and atmospheric dynamics (climatology, turbulence, instruments and techniques

  2. 覆盖免耕对棉田土壤物理性质及棉花生理特性的影响%Effects of Straw Mulch and Zero Tillage on Soil Physical Properties and Cotton Physiological Characteristics

    Institute of Scientific and Technical Information of China (English)

    郑曙峰; 王维; 徐道青; 屈磊

    2011-01-01

    The experiment was conducted with the split plot design to study the effects of straw mulch and zero tillage on the temperature and bulk density of soil, the SPAD value of functional leaves, photosynthetic characteristics and growth situation of cotton. The results showed that the temperature and bulk density of soil,the net photosynthetic rate (Pn), stomatal conductance (Gs), inter CO2 concentration (Ci), transpiration rate (Tr)of cotton were lower in zero tillage treatments than in tillage treatments, while the SPAD value of functional leaves was higher. The temperature of soil was lower in straw mulch treatments than in other treatments, while the moisture was higher. In zero tillage treatments, the bulk density of soil, the stomatal conductance (Cs), inter CO2 concentration (Ci), transpiration rate (Tr) of cotton were higher in straw mulch condition than in other conditions, which was opposite in tillage treatments. The bolls had no variety among with zero tillage treatments and tillage treatments. The bolls, boll weight and lint percentage was higher in straw mulch treatments than in no mulch treatments. The SPAD value of functional leaves was decreased with the increasing of straw mulch quantity, while the yield was increased. The photosynthetic characteristics and yields of cotton under the condition of straw mulch and zero tillage were lower than under the condition of tillage. The yield had no variety among with different mulches.%采用裂区设计,研究了秸秆覆盖及免耕对土壤温度、容重及棉花功能叶SPAD值、光合特性、生育性状等的影响.结果表明:免耕降低土壤温度、容重以及棉花的净光合速率、气孔导度、胞间CO2浓度、蒸腾速率,但功能叶SPAD值为免耕>翻耕;秸秆覆盖降低土壤温度,提高土壤含水量;免耕下秸秆覆盖较地膜覆盖和露地提高土壤容重及棉花的气孔导度、胞间CO2浓度、蒸腾速率,翻耕时结果与此相反;翻耕处理棉花长势强

  3. 耕作方式对冀西北栗钙土土壤物理性状及莜麦生长的影响%Effects of tillage mode on chestnut soil’s physical characters and naked oats growth in Northwest Hebei province

    Institute of Scientific and Technical Information of China (English)

    王岩; 刘玉华; 张立峰; 窦铁岭

    2014-01-01

    为了探索不同耕作方式对冀西北栗钙土农田土壤物理性状及莜麦生长的影响,以河北省张北县10 a栗钙土长期定位试验莜麦田为研究对象,研究了免耕、松耕和翻耕对莜麦田土壤容重、土壤含水率、土壤硬度及莜麦生长的影响。结果表明:松耕和翻耕可以显著降低莜麦播种期到拔节期土壤容重,播种期免耕土壤容重1.49 g/cm3,松耕和翻耕分别为1.31和1.30 g/cm3;不同耕作方式对土壤含水率影响不大;免耕显著提高土壤硬度,拔节期免耕土壤硬度58.51kg/cm2,为松耕1.74倍(P<0.05),为翻耕2.53倍(P<0.01);栗钙土土壤硬度与土壤容重、土壤含水率关系模型表明高土壤容重条件下土壤硬度对土壤含水率更敏感,低土壤含水率条件下土壤硬度对土壤容重更敏感;免耕莜麦株高和叶面积生长受到抑制,穗数和穗粒数显著降低,经济产量413.79 kg/hm2,分别为松耕和翻耕的62.27%和51.64%。栗钙土莜麦田免耕与松耕、翻耕相比土壤容重大,土壤硬度高,莜麦产量显著降低;3种耕作方式中,松耕是兼顾生态与经济效益的耕作措施。%Taking a ten-year naked oats field experiment site in Zhangbei county of Hebei province as the test object, this paper studied the effects of different tillage modes (no tillage, subsoiling tillage, and conventional tillage) on the soil physical characteristics and naked oats growth in chestnut soil. The no tillage treatment soil was undisturbed from last year’s harvesting to sowing, with 15-22 cm stubbles; broad-spectrum herbicide was used in soil treatment before planting and sprayed in seedling. The subsoiling tillage treatment plowed the soil after the previous year’s harvest, used the self-developed‘Parallel rod without wall subsoiling plow’ (Patent No.:2011202468728) with a plowed depth of 15-22 cm, and was sowed and fertilized in the same manner as the no tillage

  4. Quantifying antiepileptic drug effects using intrinsic excitability measures.

    Science.gov (United States)

    Meisel, Christian; Plenz, Dietmar; Schulze-Bonhage, Andreas; Reichmann, Heinz

    2016-11-01

    Pathologic increases in excitability levels of cortical tissue commonly underlie the initiation and spread of seizure activity in patients with epilepsy. By reducing the excitability levels in neural tissue, antiepileptic drug (AED) pharmacotherapy aims to reduce seizure severity and frequency. However, AEDs may also bring about adverse effects, which have been reported to increase with higher AED load. Measures that monitor the dose-dependent effects of AEDs on cortical tissue and quantify its excitability level are therefore of prime importance for efficient clinical care and treatment but have been difficult to identify. Here, we systematically analyze continuous multiday electrocorticography (ECoG) data from 10 patients under different levels of AED load and derive the recently proposed intrinsic excitability measures (IEMs) from different brain regions and across different frequency bands. We find that IEMs are significantly negatively correlated with AED load (prescribed daily dose/defined daily dose). Furthermore, we demonstrate that IEMs derived from different brain regions can robustly capture global changes in the degree of excitability. These results provide a step toward the ultimate goal of developing a reliable quantitative measure of central physiologic effects of AEDs in patients with epilepsy. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

  5. Upscaling nitrogen-mycorrhizal effects to quantify CO2 fertilization.

    Science.gov (United States)

    Terrer, C.; Franklin, O.; Kaiser, C.; Vicca, S.; Stocker, B.; Prentice, I. C.; Soudzilovskaia, N.

    2016-12-01

    Terrestrial ecosystems sequester annually about a quarter of anthropogenic carbon dioxide (CO2) emissions. However, it has been proposed that nitrogen (N) availability will limit plants' capacity to absorb increasing quantities of CO2 in the atmosphere. Experiments in which plants are fumigated with elevated CO2 show contrasting results, leaving open the debate of whether the magnitude of the CO2 fertilization effect will be limited by N. By synthesizing data from CO2 experiments through meta-analysis, we found that the magnitude of the CO2 fertilization effect can be explained based on the interaction between N availability and type of mycorrhizal association. Indeed, N availability is the most important driver of the CO2 fertilization effect, however, plants that associate with ectomycorrhizal fungi can overcome N limitations and grow about 30% more under 650ppm than under 400ppm of atmospheric CO2. On the other hand, plants that associate with arbuscular mycorrhizal fungi show no CO2 fertilization effect under low N availability. Using this framework, we quantified biomass responses to CO2 as a function of the soil parameters that determine N availability for the two mycorrhizal types. Then, by overlaying the distribution of mycorrhizal plants with global projections of the soil parameters that determine N availability, we estimated the amount of extra CO2 that terrestrial plants can sequester in biomass for an increase in CO2, as well as the distribution of the CO2 fertilization effect. This synthesis reconciles contrasting views of the role of N in terrestrial carbon uptake and emphasizes the plant control on N availability through interaction with ectomycorrhizal fungi. Large-scale ecosystem models should account for the influence of nitrogen and mycorrhizae reported here, which will improve representation of the CO2 fertilization effect, critical for projecting ecosystem responses and feedbacks to climate change.

  6. Tillage, mulch and N fertilizer affect emissions of CO2 under the rain fed condition.

    Science.gov (United States)

    Tanveer, Sikander Khan; Wen, Xiaoxia; Lu, Xing Li; Zhang, Junli; Liao, Yuncheng

    2013-01-01

    A two year (2010-2012) study was conducted to assess the effects of different agronomic management practices on the emissions of CO2 from a field of non-irrigated wheat planted on China's Loess Plateau. Management practices included four tillage methods i.e. T1: (chisel plow tillage), T2: (zero-tillage), T3: (rotary tillage) and T4: (mold board plow tillage), 2 mulch levels i.e., M0 (no corn residue mulch) and M1 (application of corn residue mulch) and 5 levels of N fertilizer (0, 80, 160, 240, 320 kg N/ha). A factorial experiment having a strip split-split arrangement, with tillage methods in the main plots, mulch levels in the sub plots and N-fertilizer levels in the sub-sub plots with three replicates, was used for this study. The CO2 data were recorded three times per week using a portable GXH-3010E1 gas analyzer. The highest CO2 emissions were recorded following rotary tillage, compared to the lowest emissions from the zero tillage planting method. The lowest emissions were recorded at the 160 kg N/ha, fertilizer level. Higher CO2 emissions were recorded during the cropping year 2010-11 relative to the year 2011-12. During cropping year 2010-11, applications of corn residue mulch significantly increased CO2 emissions in comparison to the non-mulched treatments, and during the year 2011-12, equal emissions were recorded for both types of mulch treatments. Higher CO2 emissions were recorded immediately after the tillage operations. Different environmental factors, i.e., rain, air temperatures, soil temperatures and soil moistures, had significant effects on the CO2 emissions. We conclude that conservation tillage practices, i.e., zero tillage, the use of corn residue mulch and optimum N fertilizer use, can reduce CO2 emissions, give better yields and provide environmentally friendly options.

  7. Tillage, mulch and N fertilizer affect emissions of CO2 under the rain fed condition.

    Directory of Open Access Journals (Sweden)

    Sikander Khan Tanveer

    Full Text Available A two year (2010-2012 study was conducted to assess the effects of different agronomic management practices on the emissions of CO2 from a field of non-irrigated wheat planted on China's Loess Plateau. Management practices included four tillage methods i.e. T1: (chisel plow tillage, T2: (zero-tillage, T3: (rotary tillage and T4: (mold board plow tillage, 2 mulch levels i.e., M0 (no corn residue mulch and M1 (application of corn residue mulch and 5 levels of N fertilizer (0, 80, 160, 240, 320 kg N/ha. A factorial experiment having a strip split-split arrangement, with tillage methods in the main plots, mulch levels in the sub plots and N-fertilizer levels in the sub-sub plots with three replicates, was used for this study. The CO2 data were recorded three times per week using a portable GXH-3010E1 gas analyzer. The highest CO2 emissions were recorded following rotary tillage, compared to the lowest emissions from the zero tillage planting method. The lowest emissions were recorded at the 160 kg N/ha, fertilizer level. Higher CO2 emissions were recorded during the cropping year 2010-11 relative to the year 2011-12. During cropping year 2010-11, applications of corn residue mulch significantly increased CO2 emissions in comparison to the non-mulched treatments, and during the year 2011-12, equal emissions were recorded for both types of mulch treatments. Higher CO2 emissions were recorded immediately after the tillage operations. Different environmental factors, i.e., rain, air temperatures, soil temperatures and soil moistures, had significant effects on the CO2 emissions. We conclude that conservation tillage practices, i.e., zero tillage, the use of corn residue mulch and optimum N fertilizer use, can reduce CO2 emissions, give better yields and provide environmentally friendly options.

  8. Spatially quantifying the leadership effectiveness in collective behavior

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Haitao [State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China); Wang Ning [Department of Control Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Chen, Michael Z Q [Department of Mechanical Engineering, University of Hong Kong, Pok Fu Lam Road, Hong Kong (Hong Kong); Su Riqi; Zhou Tao [Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China); Zhou Changsong, E-mail: zht@mail.hust.edu.cn, E-mail: cszhou@hkbu.edu.hk, E-mail: zhutou@ustc.edu [Department of Physics, Centre for Nonlinear Studies, and Beijing-Hong Kong-Singapore Joint Centre for Nonlinear and Complex Systems (Hong Kong), Hong Kong Baptist University, Kowloon Tong (Hong Kong)

    2010-12-15

    Among natural biological flocks/swarms or mass social activities, when the collective behavior of the followers has been dominated by the direction or opinion of one leader group, it seems difficult for later-coming leaders to reverse the orientation of the mass followers, especially when they are in quantitative minority. This paper, however, reports a counter-intuitive phenomenon, i.e. Following the Later-coming Minority, provided that the later-comers obey a favorable distribution pattern that enables them to spread their influence to as many followers as possible within a given time and to be dense enough to govern these local followers they can influence directly from the beginning. We introduce a discriminant index to quantify the whole group's orientation under competing leaderships, with which the eventual orientation of the mass followers can be predicted before launching the real dynamical procedure. From the application point of view, this leadership effectiveness index also helps us to design an economical way for the minority later-coming leaders to defeat the dominating majority leaders solely by optimizing their spatial distribution pattern provided that the premeditated goal is available. Our investigation provides insights into effective leadership in biological systems with meaningful implications for social and industrial applications.

  9. Soil water retention as affected by tillage and residue management in semiarid Spain

    NARCIS (Netherlands)

    Bescansa, P.; Imaz, M.J.; Virto, I.; Enrique, A.; Hoogmoed, W.B.

    2006-01-01

    Conservation tillage preserves soil water and this has been the main reason for its rapid dissemination in rainfed agriculture in semiarid climates. We determined the effects of conservation versus conventional tillage on available soil water capacity (AWC) and related properties at the end of 5 yea

  10. Influence of reduced tillage on earthworm and microbial communities under organic arable farming

    NARCIS (Netherlands)

    Kuntz, M.; Berner, A.; Gattinger, A.; Scholberg, J.M.S.; Mäder, P.; Pfiffner, L.

    2013-01-01

    Although reduced tillage is an agricultural practice reported to decrease soil erosion and external inputs while enhancing soil fertility, it has still rarely been adopted by European organic farmers. The objective of this study was to assess the long-term interactive effects of tillage (conventiona

  11. 东北黑土区典型坡面耕作侵蚀定量分析%Quantitative assessment of tillage erosion on typical sloping field in black soil area of northeast China

    Institute of Scientific and Technical Information of China (English)

    赵鹏志; 陈祥伟; 王恩姮

    2016-01-01

    东北黑土区水土流失主要集中在坡耕地,以往研究多关注水蚀而忽略了耕作侵蚀的存在.为印证并定量描述黑土耕作侵蚀,该文采用物理示踪法,测定了典型坡耕地耕作位移量及其分布格局.结果表明:铧式犁耕作后示踪剂沿耕作方向发生扩散,上坡耕作示踪剂集中分布在0~20 cm范围,而下坡耕作示踪剂集中分布在0~20和50~150 cm.一次耕作引起的耕作位移量为32.68~134.14 kg/m,耕作迁移系数234 kg/m.坡度是影响耕作位移的重要因素,二者呈显著的正相关关系,且对上坡耕作的影响大于下坡耕作.研究区耕作年侵蚀速率0.4~11.0 Mg/(hm2·a),凸起的坡背、坡肩处及坡度较大的位置侵蚀严重.虽然黑土区坡度较小,但由于耕作深度大,速度快,耕作侵蚀严重,应引起足够重视.%Massive research on soil erosion in northeastern China has focused on quantifying the rates and patterns of water erosion. Soil transportation caused by farming equipments or tillage erosion, however, has largely been overlooked as a significant geomorphic process in the black soil region. The objectives of this study, therefore, were to 1) quantatively determine tillage translocation value due to moldboard plowing, which was the predominant implement of soil preparation in this area; 2) to examine the effect of slope gradient and tillage direction on tillage translocation; and 3) to investigate the spatial distribution of tillage erosion in a typical sloping cultivated land. Tillage translocation process was determined by labeling method in this study. White quartz gravel with 6-12 mm in diameter was used as the tracer for all the plots. A summation curve was generated to calculate mean soil movement based on tracer redistribution along the path of tillage. Tillage operations were conducted in both up and down direction of the sloping field separately, and the mean slope was 3.6° with maximum up to 7.2°. Speed and depth of tillage were

  12. Simulation of Tillage Systems Impact on Soil Biophysical Properties Using the SALUS Model

    Directory of Open Access Journals (Sweden)

    Luigi Sartori

    2011-02-01

    Full Text Available A sustainable land management has been defined as the management system that allows for production, while minimizing risk, maintaining quality of soil and water. Tillage systems can significantly decrease soil carbon storage and influence the soil environment of a crop. Crop growth models can be useful tools in evaluating the impact of different tillage systems on soil biophysical properties and on the growth and final yield of the crops. The objectives of this paper were i to illustrate the SALUS model and its tillage component; ii to evaluate the effects of different tillage systems on water infiltration and time to ponding, iii to simulate the effect of tillage systems on some soil biophysical properties. The SALUS (System Approach to Land Use Sustainability model is designed to simulate continuous crop, soil, water and nutrient conditions under different tillage and crop residues management strategies for multiple years. Predictions of changes in surface residue, bulk density, runoff, drainage and evaporation were consistent with expected behaviours of these parameters as described in the literature. The experiment to estimate the time to ponding curve under different tillage system confirmed the theory and showed the beneficial effects of the residue on soil surface with respect to water infiltration. It also showed that the no-tillage system is a more appropriate system to adopt in areas characterized by high intensity rainfall.

  13. 保护性耕作和杂草管理对冬小麦农田土壤水分及有机碳的影响%Effects of conservation tillage and weed control on soil water and organic carbon contents in winter wheat field

    Institute of Scientific and Technical Information of China (English)

    韩惠芳; 宁堂原; 李增嘉; 田慎重; 王瑜; 仲惟磊; 田欣欣

    2011-01-01

    在秸秆全量还田的试验田中(从2004年起),于2008-2009年及2009-2010年冬小麦生育期间,研究了不同耕作措施(旋耕、耙耕、免耕、深松和常规耕作)和杂草管理对冬小麦田土壤水分及有机碳的影响.结果表明:在未除草条件下,免耕、深松的杂草总密度显著提高;而在除草条件下,杂草密度显著下降.小麦从拔节期到灌浆期0~60 cm土层水分含量呈明显波动变化,田间保留一定量的杂草可增加不同耕作方式0~20 cm的土壤水分含量,表现出一定的土壤水分保持效应.保留杂草仅提高了拔节期0~20 cm土层的土壤有机碳含量;而在抽穗期和灌浆期,0~20、20~40和40~60 cm土层有机碳含量均低于去除杂草处理.去除杂草条件下,深松显著提高了冬小麦籽粒产量;保留杂草条件下,旋耕的籽粒产量最高,常规耕作产量最低.%Taking a long term ( since 2004) straw-returning winter wheat field as the object, an investigation was made in the wheat growth seasons of 2008-2009 and 2009-2010 to study the effects of different tillage methods ( rotary tillage, harrow tillage, no-tillage, subsoil tillage, and conven tional tillage) and weed management on the soil water and organic carbon contents. No matter retaining or removing weeds, the weed density under subsoil tillage and no-tillage was much higher than that under rotary tillage, harrow tillage, and conventional tillage. From the jointing to the milking stage of winter wheat, retaining definite amounts of weeds, no matter which tillage method was adopted, could significantly increase the 0-20 cm soil water content, suggesting the soil water conservation effect of retaining weeds. Retaining weeds only increased the soil organic carbon content in 0-20 cm layer at jointing stage. At heading and milking stages, the soil organic carbon contents in 0-20, 20-40, and 40-60 cm layers were lower under weed retaining than under weed removal.Under the conditions of

  14. Pitfalls in quantifying species turnover: the residency effect

    OpenAIRE

    Kevin Chase Burns

    2014-01-01

    The composition of ecological communities changes continuously through time and space. Understanding this turnover in species composition is a central goal in biogeography, but quantifying species turnover can be problematic. Here, I describe an underappreciated source of bias in quantifying species turnover, namely ‘the residency effect’, which occurs when the contiguous distributions of species across sampling domains are small relative to census intervals. I present the results of a simula...

  15. Effect of {sup 15}n-labeled hairy vetch and nitrogen fertilization on maize nutrition and yield under no-tillage

    Energy Technology Data Exchange (ETDEWEB)

    Almeida Acosta, Jose Alan de [Drakkar Solos, Santa Maria, RS (Brazil); Amado, Telmo Jorge Carneiro; Silva, Leandro Souza da, E-mail: tamado@smail.ufsm.b, E-mail: leandro@smail.ufsm.b [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Soil Dept.; Neergaard, Andreas de; Vinther, Mads, E-mail: adn@life.ku.d [University of Copenhagen (Denmark); Silveira Nicoloso, Rodrigo da, E-mail: rodrigo.nicoloso@cnpsa.embrapa.b [Embrapa Swine and Poultry, Concordia, SC (Brazil)

    2011-07-15

    This study evaluated the effect of hairy vetch (Vicia villosa Roth) as cover crop on maize nutrition and yield under no tillage using isotope techniques. For this purpose, three experiments were carried out: quantification of biological nitrogen fixation (BNF) in hairy vetch; estimation of the N release rate from hairy vetch residues on the soil surface; quantification of {sup 15}N recovery by maize from labeled hairy vetch under three rates of mineral N fertilization. This two year field experiment was conducted on a sandy Acrisol (FAO soil classification) or Argissolo Vermelho distrofico arenico (Brazilian Soil Classification), at a mean annual temperature of 18 deg C and mean annual rainfall of 1686 mm. The experiment was arranged in a double split-plot factorial design with three replications. Two levels of hairy vetch residue (50 and 100 % of the aboveground biomass production) were distributed on the surface of the main plots (5 x 12 m). Maize in the sub-plots (5 x 4 m) was fertilized with three N rates (0, 60, and 120 kg ha{sup -1} N), with urea as N source. The hairy vetch-derived N recovered by maize was evaluated in microplots (1.8 x 2.2 m). The BFN of hairy vetch was on average 72.4 %, which represents an annual input of 130 kg ha{sup -1} of atmospheric N. The N release from hairy vetch residues was fast, with a release of about 90 % of total N within the first four weeks after cover crop management and soil residue application. The recovery of hairy vetch {sup 15}N by maize was low, with an average of 12.3 % at harvest. Although hairy vetch was not directly the main source of maize N nutrition, the crop yield reached 8.2 Mg ha{sup -1}, without mineral fertilization. There was an apparent synergism between hairy vetch residue application and the mineral N fertilization rate of 60 kg ha{sup -1}, confirming the benefits of the combination of organic and inorganic N sources for maize under no tillage. (author)

  16. Effects of Different Tillage Methods on Physical, Chemical Properties and Nutrient of Soil in Tea Plantation%不同耕作方式对茶园土壤理化性质和养分的影响

    Institute of Scientific and Technical Information of China (English)

    向芬; 宋志禹; 周凌云; 李维; 刘红艳; 段继华; 周品谦; 包小村; 肖宏儒

    2016-01-01

    Taking no tillage as the check, we studied the effects of different tillage methods on the physical, chemical prop-erties and nutrient of soil in tea plantation .The results indicated that:during 2~4 months after tea plantation was tilled by differ-ent methods (intertillage, deep ploughing by hand, or deep ploughing by tractor), in comparison with the check, the soil relative water content and bulk density were decreased, while the tea root dry weight, and contents of available nitrogen, available phos-phorus and available potassium in 20~40-cm soil layer of tea plantation were increased.The above results suggest that reasonable tillage is in favor of the tea root growth and tea garden soil nutrient equilibrium , and deep plowing and intertillage by using tillage machine are feasible in tea garden.%以不耕作为对照,研究了不同耕作方式对茶园土壤理化性质和养分含量的影响。结果表明:中耕、手扶深耕、拖拉机深耕2~4个月后土壤相对含水量和土壤容重较对照低,但茶园的根系干重以及20~40 cm土层的碱解氮、速效磷、速效钾含量均有所增加。说明合理耕作有利于茶树根系生长和茶园土壤养分的均衡;使用耕作机对茶园进行深耕、中耕均是可行的。

  17. 保护性耕作方式对土壤微生物生理类群和酶活性的影响%Effects of conservation tillage on soil microbial physiologies colony and enzyme activities

    Institute of Scientific and Technical Information of China (English)

    王静; 张仁陟; 张天佑

    2011-01-01

    Based on different tillages experiment in Dingxi,the effects of soil microbial physiologies colony,soil enzyma activities and their relationship under different conversation tillage measures(no-tillage and straw cover,plough with straw incorporated,no-til%通过设置在甘肃省定西市安定区李家堡乡的田间定位试验,研究了不同耕作方式下(NTS、TS、NT、T)土壤微生物生理类群数量和酶活性及其相关性。结果表明:与传统耕作(T)相比,保护性耕作方式(NTS、TS、NT)能显著增加土壤微生物生理类群数量,增强酶活性。不同的保护性耕作方式下,土壤微生物生理类群数量和酶活性存在显著差异。相关性分析表明,土壤微生物生理类群数量和酶活性间大部分呈显著或极显著正相关。

  18. Phosphorus and nitrogen leaching before and after tillage and urea application.

    Science.gov (United States)

    Han, Kun; Kleinman, Peter J A; Saporito, Lou S; Church, Clinton; McGrath, Joshua M; Reiter, Mark S; Tingle, Shawn C; Allen, Arthur L; Wang, L Q; Bryant, Ray B

    2015-03-01

    Leaching of nutrients through agricultural soils is a priority water quality concern on the Atlantic Coastal Plain. This study evaluated the effect of tillage and urea application on leaching of phosphorus (P) and nitrogen (N) from soils of the Delmarva Peninsula that had previously been under no-till management. Intact soil columns (30 cm wide × 50 cm deep) were irrigated for 6 wk to establish a baseline of leaching response. After 2 wk of drying, a subset of soil columns was subjected to simulated tillage (0-20 cm) in an attempt to curtail leaching of surface nutrients, especially P. Urea (145 kg N ha) was then broadcast on all soils (tilled and untilled), and the columns were irrigated for another 8 wk. Comparison of leachate recoveries representing rapid and slow flows confirmed the potential to manipulate flow fractions with tillage, albeit with mixed results across soils. Leachate trends in the finer-textured soil suggest that tillage impeded macropore flow and forced greater matrix flow. Despite significant vertical stratification of soil P that suggested tillage could prevent leaching of P via macropores from the surface to the subsoil, tillage had no significant impact on P leaching losses. Relatively high levels of soil P below 20 cm may have served as the source of P enrichment in leachate waters. However, tillage did lower losses of applied urea in leachate from two of the three soils, partially confirming the study's premise that tillage would destroy macropore pathways transmitting surface constituents to the subsoil.

  19. Simulated responses of soil organic carbon stock to tillage management scenarios in the Northwest Great Plains

    Directory of Open Access Journals (Sweden)

    Li Zhengpeng

    2007-07-01

    Full Text Available Abstract Background Tillage practices greatly affect carbon (C stocks in agricultural soils. Quantification of the impacts of tillage on C stocks at a regional scale has been challenging because of the spatial heterogeneity of soil, climate, and management conditions. We evaluated the effects of tillage management on the dynamics of soil organic carbon (SOC in croplands of the Northwest Great Plains ecoregion of the United States using the General Ensemble biogeochemical Modeling System (GEMS. Tillage management scenarios included actual tillage management (ATM, conventional tillage (CT, and no-till (NT. Results Model simulations show that the average amount of C (kg C ha-1yr-1 released from croplands between 1972 and 2000 was 246 with ATM, 261 with CT, and 210 with NT. The reduction in the rate of C emissions with conversion of CT to NT at the ecoregion scale is much smaller than those reported at plot scale and simulated for other regions. Results indicate that the response of SOC to tillage practices depends significantly on baseline SOC levels: the conversion of CT to NT had less influence on SOC stocks in soils having lower baseline SOC levels but would lead to higher potentials to mitigate C release from soils having higher baseline SOC levels. Conclusion For assessing the potential of agricultural soils to mitigate C emissions with conservation tillage practices, it is critical to consider both the crop rotations being used at a local scale and the composition of all cropping systems at a regional scale.

  20. Sediment yield control in vineyards covered with cereal. Effect of tillage; Control de la perdida de suelo en vinedos con cubiertas de gramineas. Efecto del laboreo

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-Colmenero, M.; Bienes, R.; Marques, M. J.

    2009-07-01

    A study has been carried out about the use of plant cover treatment to avoid land degradation in a hillside rainfed vineyard in Madrid under Mediterranean semiarid climate. Three treatments were tested: traditional tillage (lab) soil covered by Brachypodium distachyon (bra) with self-sowing, soil covered by Scale cereale (sec) mown in Spring. Three erosion plots per treatment were placed in the middle of the strips and 2 simulated rainfalls were carried out at each plot in autumn, before and after the tillage. (Author) 7 refs.

  1. Improvement of native grassland by legumes introduction and tillage techniques

    Directory of Open Access Journals (Sweden)

    Syamsu Bahar

    1999-10-01

    Full Text Available A factorial design using three species of legumes (Siratro, Centro and Stylo and three different of tillage techniques (no-tillage, minimum tillage and total tillage was applied in this experiment. The results showed that there was no interaction between species and tillage techniques. There was significant reductions on bulk density from 1.23±0.03 g/cm3 (no-tillage to 1.07±0.02 g/cm3 (minimum tillage and 1.05±0.03 g/cm3 (total tillage. Also reductions on penetration resistance from 17.47±3.84 kg/cm2 (no-tillage to 3.31±0.43 kg/cm2 (minimum tillage and 3.19±0.45 kg/cm2 (total tillage. Otherwise significant increasing on aeration porosity from 12.80±0.80% vol. (no-tillage to 21.70±0.95% vol. (minimum tillage and 20.70±0.35% vol. (total tillage. Total tillage gives increased dry matter yield. Also both total tillage and minimum tillage give yields with a higher percentage of legumes compared with no-tillage. It was concluded that total tillage and minimum tillage could be used for improving native grassland.

  2. African Conservation Tillage Network Website

    OpenAIRE

    African Conservation Tillage Network (ACT)

    2009-01-01

    Metadata only record Maintained by the African Conservation Tillage Network (ACT), this website provides information on Conservation Agriculture in an African context and gathered by stakeholders (NGOs) native to the continent. Resources on projects, practices, reports, and training courses are provided.

  3. Effects of conservation tillage on soil photosynthetic bacteria and typeⅡ methanotrophs%保护性耕作对土壤光合细菌和Ⅱ型甲烷氧化菌的影响

    Institute of Scientific and Technical Information of China (English)

    王敬敬; 李新宇; 徐明恺; 苏振成; 李旭; 孙健; 张惠文

    2012-01-01

    保护性耕作对土壤微生物具有明显的保护效应,但是其对土壤光合细菌和甲烷氧化菌的影响却鲜有报道.本文采用土壤宏基因组16S rDNA变性梯度凝胶电泳(DGGE)和荧光定量PCR技术比较了不同耕作模式(免耕和传统翻耕)和不同秸秆覆盖量(0、50%、100%)对潮土中光合细菌和Ⅱ型甲烷氧化菌数量和群落结构的影响.结果表明:免耕土壤中光合细菌的多样性(多样性指数H=2.47)显著高于传统翻耕土壤(多样性指数H=2.35),且与土壤总氮呈显著正相关,数量略低于传统翻耕土壤;光合细菌的数量和多样性虽均随着秸秆覆盖量的增加而有所增加,但不显著;虽然免耕和秸秆覆盖对Ⅱ型甲烷氧化菌数量和多样性产生了有益的影响,但是耕作模式、秸秆覆盖及二者互作对其影响均不显著;不同处理中光合细菌和Ⅱ型甲烷氧化菌的种群结构无明显变化,光合细菌优势种群以根瘤菌目(Rhizobiales)和鞘脂单胞菌目(Sphingomonadales)为主,Ⅱ型甲烷氧化菌优势种群主要为甲基孢囊菌科(Methylocystaceae)的细菌类群.%Conservation tillage has beneficial effects on soil microbes, but the effects on soil photosynthetic,bacteria and methanotrophs are rarely reported. In this study, denaturing gel gradient electrophoresis (DGGE) and quantitative PCR technique were adopted to investigate the abundance and community structure of photosynthetic bacteria and type Ⅱ methanotrophs in a fluvo-aquic soil as affected by different tillage modes ( no-tillage and conventional tillage) and straw mulching (0, 50% , 100% ). Under no tillage, the diversity of soil photosynthetic bacteria was significantly higher but the abundance was slightly lower, as compared with those under conventional tillage, and there was a significant positive correlation between the diversity of soil photosynthetic bacteria and the soil total nitrogen. Both the abundance and the diversity of soil

  4. Pitfalls in quantifying species turnover: the residency effect

    Directory of Open Access Journals (Sweden)

    Kevin Chase Burns

    2014-03-01

    Full Text Available The composition of ecological communities changes continuously through time and space. Understanding this turnover in species composition is a central goal in biogeography, but quantifying species turnover can be problematic. Here, I describe an underappreciated source of bias in quantifying species turnover, namely ‘the residency effect’, which occurs when the contiguous distributions of species across sampling domains are small relative to census intervals. I present the results of a simulation model that illustrates the problem theoretically and then I demonstrate the problem empirically using a long-term dataset of plant species turnover on islands. Results from both exercises indicate that empirical estimates of species turnover may be susceptible to significant observer bias, which may potentially cloud a better understanding of how the composition of ecological communities changes through time.

  5. 耕作措施对东北黑土微生物呼吸的影响%Effect of Conservation Tillage on Microbial Respiration of Black Soil

    Institute of Scientific and Technical Information of China (English)

    贾淑霞; 孙冰洁; 梁爱珍; 陈学文; 张士秀; 魏守才; 刘四义; 陈升龙; 张晓平

    2015-01-01

    耕作处理只改变了5 cm的Q10值,免耕比秋翻高10.8%。土壤微生物呼吸速率与土壤温度、水分混合回归模型能更好地反应其变化规律,解释土壤微生物呼吸速率变异的65%(秋翻)和81%(免耕)。【结论】免耕增加了表层(0—5 cm)的SOC含量,从而使得该土层的土壤微生物量碳和活性增加,但是由于免耕处理增加0—30 cm 土层SOC含量的加权平均值,因此相对于传统的耕作措施(秋翻),免耕有利于SOC含量的增加。%Objective] In this study, soil microbial activity and biomass carbon under 13-year conservation tillage (no-till) were assessed in a black soil agro-ecosystem in northeast China in order to determine the effect of tillage treatment on soil organic carbon and soil microbial biomass, which would provide a theoretical basis for valuing the ‘sink’ or ‘source’ function of soil carbon pool.[Method] The present study was conducted as part of a long term tillage experiment on the continuous maize (Zea mays L.), tillage treatments consisted of no-tillage (NT), and mouldboard plough (MP). The NT treatment had no soil disturbance except planting, crop residues were left on soil surface after harvest. The MP treatment included one fall mouldboard plough (about 15 cm in depth) after maize harvest, one disking (7.5 to 10 cm in depth) in spring and field cultivation (ridging in June). Soil respiration without roots represented soil microbial respiration, which was measured biweekly from 14 June 2012 to 25 September 2013 using LI-8100 automated soil CO2 flux system (LI-COR Inc., Lincoln, NE, USA), soil microbial biomass and the number of colony forming units of bacteria (cfub), fungi (cfuf), and actinomyces (cfua) were measured during the soil microbial respiration was the highest.[Result] It was found that the range of soil microbial respiration was 0.42-3.35μmolCO2·m-2·s-1under NT and 0.48-3.24μmolCO2·m-2·s-1under MP during growing season, the average soil

  6. 水稻连续免耕抛栽对土壤理化和生物学性状的影响%EFFECTS OF CONTINUOUS NO TILLAGE AND CAST TRANSPLANTING ON SOIL PHYSICAL, CHEMICAL AND BIOLOGICAL PROPERTIES

    Institute of Scientific and Technical Information of China (English)

    吴建富; 潘晓华; 石庆华; 漆英雪; 刘宗发; 胡金和

    2009-01-01

    A three year (2005~2007) experiment was conducted in paddy fields under a double rice cropping system to study effects of continuous no tillage and cast-transplanting on soil physical, chemical and biological properties. Results show that no-tillage treatment for one year (two crops)improved soil physical properties, but no-tillage treatment for three years (six crops), worsened soil physical properties. However, the effect of no tillage treatment for two years varied. In the soil incorporated with milk vetch and rice straw, it decreased soil density of the cultivated horizon, but increased total porosity and non-capillary porosity therein, and helped nutrient enrichment in the surface soil layer. Soil analysis showed that the no-tillage field was less than the control, plowed field in total amount of three groups of soil microbes. However, in no-tillage field, the amount of soil bacteria increased, while that of soil actinomycosis and fungi reduced, and urease activity in surface layer soil increased, while catalase and peroxidase activity reduced. Significantly positive correlations were observed of soil organic matter and total N with urease, catalase and polyphenol oxidase activity and, significantly positive correlations of soil total N and available K with peroxidase activity and. The findings provide a valuable reference for popularization and application of the technology of no-tillage and cast transplantation of rice in the future.%于2005~2007年在双季稻田以翻耕处理为对照,研究了水稻连续免耕抛栽对土壤理化和生物学性质的影响.结果表明,稻田免耕1年(2季),有利于土壤物理性状的改善,随着免耕时间(3年6季)的延长,土壤物理性质变差.但免耕2年后,采用紫云英和稻草还田能降低免耕稻田的土壤容重,提高总孔隙度和非毛管孔隙度.免耕有利于土壤养分在表层土壤富集.土壤中三大类微生物总量免耕处理小于翻耕处理,免耕土壤细菌的数

  7. Effects of Different Tillage Methods on Soil Properties and Crop Yields in Arid Saline Region%干旱盐碱区耕作方式改变对土壤性状和作物产量的影响

    Institute of Scientific and Technical Information of China (English)

    巨兆强; 刘小京

    2012-01-01

    To explore the effective tillage method for increasing the utilization efficiency of water resources and crop yield in arid saline region around the Bohai sea,the summer maize deep tillage-winter wheat furrow sowing method and the traditional rotary tillage planting method were compared,and the effects of different tillage methods on soil properties and crop yields were analyzed by comparative test.The results showed that deep tillage improved soil physical properties,bulk density of top soil was decreased by 0.5 g/cm3,and porosity was increased by 5.0%,saturated hydraulic conductivity was increased by several orders of magnitude.Soil water content at 20-40 cm was increased by 6.7%,which benefited to crop absorption and utilization.Salt content in topsoil was not increased with water content,so there was not potential harm of secondary salinization.The yields of summer maize and winter wheat were increased by 24% and by 52%,respectively.Thus deep tillage and furrow sowing significantly increased grain production ability in arid saline region.And the integrated methods of summer maize deep tillage-winter wheat furrow sowing could provide technical support for land and water utilization in arid saline region around the Bohai sea.%为了探索提高环渤海干旱盐碱地区水资源利用效率和作物产量的有效耕作模式,采用对比试验设计,分析了夏玉米深松播种-冬小麦沟播一体化技术与传统旋耕播种技术的土壤性质和作物产量变化。结果表明:土壤深松措施改善了耕层土壤的物理性状,上层土壤容重降低0.5 g/cm3,孔隙度增加5.0%,饱和导水率增加几个数量级;20~40 cm土壤含水量增加6.7%,利于作物吸收利用,上层土壤含盐量随含水量的增减相应地变化,并没有出现增加趋势,不存在次生盐渍化的潜在为害;夏玉米和冬小麦分别增产24%和52%,显著提升了干旱盐碱区粮食增产能力。夏玉米深松播种-冬小麦沟播一体化技术

  8. 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%Effect of Annual Tillage Practices on Soil Nutrient and Crop Yield in Lime Concretion Black Soil Farmland

    Institute of Scientific and Technical Information of China (English)

    谢迎新; 郭天财; 贺德先; 靳海洋; 李梦达; 翟羽雪; 王永华; 谢耀丽; 李向东; 夏来坤; 王晨阳

    2016-01-01

    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。%In order to select the appropriate tillage practices, improving soil nutrient and grain yield of crop grown in lime concre-tion black soil farmland, the effects of five year winter wheat-summer maize annual tillage practices (no tillage–rotary tillage, no tillage–deep tillage, subsoiling tillage–rotary tillage, subsoiling tillage–no tillage, no tillage–no tillage) on soil organic carbon content, soil nutrient and

  9. Soil greenhouse gas emissions affected by irrigation, tillage, crop rotation, and nitrogen fertilization.

    Science.gov (United States)

    Sainju, Upendra M; Stevens, William B; Caesar-Tonthat, Thecan; Liebig, Mark A

    2012-01-01

    Management practices, such as irrigation, tillage, cropping system, and N fertilization, may influence soil greenhouse gas (GHG) emissions. We quantified the effects of irrigation, tillage, crop rotation, and N fertilization on soil CO, NO, and CH emissions from March to November, 2008 to 2011 in a Lihen sandy loam in western North Dakota. Treatments were two irrigation practices (irrigated and nonirrigated) and five cropping systems (conventional-tilled malt barley [ L.] with N fertilizer [CT-N], conventional-tilled malt barley with no N fertilizer [CT-C], no-tilled malt barley-pea [ L.] with N fertilizer [NT-PN], no-tilled malt barley with N fertilizer [NT-N], and no-tilled malt barley with no N fertilizer [NT-C]). The GHG fluxes varied with date of sampling and peaked immediately after precipitation, irrigation, and/or N fertilization events during increased soil temperature. Both CO and NO fluxes were greater in CT-N under the irrigated condition, but CH uptake was greater in NT-PN under the nonirrigated condition than in other treatments. Although tillage and N fertilization increased CO and NO fluxes by 8 to 30%, N fertilization and monocropping reduced CH uptake by 39 to 40%. The NT-PN, regardless of irrigation, might mitigate GHG emissions by reducing CO and NO emissions and increasing CH uptake relative to other treatments. To account for global warming potential for such a practice, information on productions associated with CO emissions along with NO and CH fluxes is needed.

  10. Effects of tillage and crop residue management on soil respiration and its mechanism%耕作方式与秸秆还田对土壤呼吸的影响及机理

    Institute of Scientific and Technical Information of China (English)

    赵亚丽; 薛志伟; 郭海斌; 穆心愿; 李潮海

    2014-01-01

    In Huang-Huai-Hai area in China, winter wheat (Triticum aestivum)/summer maize (Zea mays) rotation is the dominant two-crop-per-year cropping system. Crop residue removal and subsoil compaction have become limiting factors for yield improvement in the area. Tillage and crop residue retained are two effective ways to improve soil properties and increase crop yield. Soil tillage and crop residue retained can reduce soil bulk density, improve water storage and aeration in the soil, increase soil microorganism and enzyme activities, improve soil biological properties, thus promote plant root growth and increase crop production. However, studies in the past mainly focused on the effects of single tillage or single crop residue retained on soil respiration. There is a need currently for research in the effects of tillage, crop residue retained and their interaction on soil respiration under the two-crop-per-year cropping system. A two-year field study from 2010 to 2012 was conducted to determine effects of tillage practice and crop residue management on soil respiration, soil temperature, soil water content, soil compaction, soil organic carbon content, dry matter accumulation of plant and root in the wheat-corn double crop cropping system. The study was conducted at the Wen County Experimental Station, Henan, China. The experiment was arranged in a split-plot design with three replications. Tillage practice and crop residue management were two factors of interest. The tillage treatment was randomly assigned to main plots and crop residue treatment was randomly assigned to sub-plots. The tillage practice treatments were: moldboard plough (MP) to a maximum depth of 15 cm, deep moldboard plough (DMP) to a maximum depth of 30 cm, and chisel plough (CP) to a maximum depth of 30 cm. All three tillage treatments were implemented after corn harvested in October of 2010 and 2011. In addition to different plough treatments, all plots were disc harrowed before wheat planting

  11. Conservation agriculture and tillage effects on soil organic matter and residual moisture content in selected upland crop production systems in the Philippines

    OpenAIRE

    Ella, Victor B.; Reyes, Manuel R.; Padre, R.; Mercado, Agustin R., Jr.

    2014-01-01

    This presentation describes a study to analyze the influence of conservation agriculture and tillage on soil organic matter and residual moisture content in selected upland crop production systems in the Philippines LTRA-12 (Conservation agriculture for food security in Cambodia and the Philippines)

  12. Conservation tillage, optimal water and organic nutrient supply enhance soil microbial activities during wheat (Triticum Aestivum L.) cultivation

    Science.gov (United States)

    Sharma, Pankaj; Singh, Geeta; Singh, Rana P.

    2011-01-01

    The field experiments were conducted on sandy loam soil at New Delhi, during 2007 and 2008 to investigate the effect of conservation tillage, irrigation regimes (sub-optimal, optimal and supra-optimal water regimes), and integrated nutrient management (INM) practices on soil biological parameters in wheat cultivation. The conservation tillage soils has shown significant (pbiofertilizer+25% Green Manure) has been used in combination with the conservation tillage and the optimum water supply. Study demonstrated that microbial activity could be regulated by tillage, water and nitrogen management in the soil in a sustainable manner. PMID:24031665

  13. Effects of tillage and straw returning on nitrogen leakage in double rice cropping field%耕作措施和秸秆还田对双季稻田土壤氮渗漏的影响

    Institute of Scientific and Technical Information of China (English)

    崔思远; 尹小刚; 陈阜; 唐海明; 李锋; 张海林

    2011-01-01

    Tillage affects the nitrogen leakage by changing soil physical and chemical properties. The effects of tillage on soil permeability and nitrogen leakage were studied for increasing utilization efficiency of nitrogen in paddy field. Long-term field experiments were established from 2005 in a double rice cropping region, Ningxiang county, Hunan province of China. Treatments included no-tillage with straw returning(NT), rotary-tillage with straw returning (RT), conventional tillage with straw returning (CT) and conventional tillage without straw returning (Cto). Constant-head method was used to analyze soil hydraulic conductivity in the soil layer 0-80 cm. Results showed that there was an increase in soil hydraulic conductivity in NT, which was 63.14% and higher than that in CT. Higher leakage of NH4+-N and NO3-N (p<0.05) were found in NT than in other treatments. Straw returning enhanced the leakage of NO3-N, especially in the period of early rice cultivation. The annual leakage of NH4+-N was almost two times than that of NO3-N among each treatment. Compared with other tillage treatments, NT could increase nitrogen leakage, and more attention should be focused on NH4+-N leakage in long-term flooding paddy fields.%针对免耕稻田土壤物理性状的改变引起的土壤氮素淋洗问题,通过定位试验研究了不同耕作措施的稻田土壤氮素特征,为免耕稻田氮素的高效利用提供依据.研究在我国双季稻典型区湖南省宁乡县长期定位试验田进行,该试验地自2005年设置免耕秸秆还田(NT)、旋耕秸秆还田(RT)、翻耕秸秆还田(CT)和翻耕秸秆不还田(CT0)4种耕作处理,重复3次.使用定水头法分层测定0~80 cm土壤导水率,测定分析各处理80cm处土壤渗漏液铵态氮、硝态氮含量差异.研究结果表明,NT 0~80 cm土壤的饱和导水率较CT提高了63.14%,NT铵态氮、硝态氮渗漏量显著高于其他处理.秸秆还田措施使早稻耕作覆水初期渗漏水中硝态

  14. Efeitos do sistema de preparo na compactação do solo, disponibilidade hídrica e comportamento do feijoeiro Effects of soil tillage on soil compaction, available soil water, and development of common bean

    Directory of Open Access Journals (Sweden)

    Luis Fernando Stone

    1999-01-01

    Full Text Available Neste trabalho foram avaliados os efeitos dos sistemas de preparo com arado de aiveca, com grade aradora e plantio direto, na compactação do solo, na disponibilidade de água, no desenvolvimento radicular e na produtividade do feijoeiro (Phaseolus vulgaris L.. A área experimental consistiu de um Latossolo Vermelho-Escuro, sob irrigação via pivô central, o que possibilitou dois cultivos ao ano. O preparo com arado propiciou menores valores de resistência à penetração, ao longo do perfil do solo. O preparo com grade condicionou uma camada mais compacta entre 10 e 24 cm de profundidade e, em plantio direto, houve maior compactação até 15 - 22 cm. A distribuição do sistema radicular, em profundidade, foi mais uniforme no preparo com arado. No preparo com grade houve concentração das raízes na camada de 0-10 cm de profundidade e, em plantio direto, a concentração ocorreu até 20 cm. Sob irrigação, a menor resistência do solo à penetração e a melhor distribuição do sistema radicular, no preparo com arado, não possibilitou ao feijoeiro obter maior produtividade em relação aos outros sistemas de preparo. A maior produtividade observada no plantio direto deveu-se, entre outros fatores, aos menores valores e à menor variação ao longo do ciclo da tensão matricial da água no solo, em comparação aos demais sistemas de preparo do solo.The effects of three tillage methods (moldboard ploughing, disking, and no-tillage on soil compaction, available soil water, root development, and common bean (Phaseolus vulgaris L. yield were evaluated. The experiment was carried out on a Dark Red Latosol, under center pivot sprinkler irrigation, which allows cropping twice a year. The soil under moldboard ploughing showed the lowest resistance to penetration throughout the profile, whereas under disking the soil showed a compacted layer between 10 and 24 cm deep. Higher compaction until 15-22 cm was observed under no-tillage. Crop roots

  15. 深耕和施用有机肥对麦田土壤微环境的影响%Effects of Deep Tillage and Organic Fertilizer Application on Soil Micro-environment of Wheat Field

    Institute of Scientific and Technical Information of China (English)

    马守臣; 张紧紧; 冯荣成; 邵云; 胡永娟; 马守田; 王文斐

    2014-01-01

    A field experiment was conducted to determine the effects of different tillage and fertilization meas-ures on the microbial quantity ,enzyme activity ,moisture and nutrients of soil .Four tillage and fertilization treatments were selected:deep tillage(DCK),deep tillage+organic fertilizer(DOF),shallow tillage(SCK),and shallow tillage+organic fertilizer(SOF).The results of 5-year field experiments showed that,without the application of organic fertilizer ,the number of fungi and actinomycetes in 0-40 cm soil layer was significantly higher in DCK than in SCK ( P<0 .05 ) ,while the number of bacteria in DCK was significantly higher only in 20-40 cm soil layer than that of SCK.Organic fertilizer could significantly increase the number of microorganisms (P<0.05).In 0-20 cm soil lay-er,the numbers of bacteria,fungi and actinomycetes in DOF treatment increased by 180.6%,53.6%and 19.8%, respectively,compared to DCK,while in SOF treatment increased by 8%,14.2% and 36.9%,respectively,com-pared to SCK .Deep tillage could increase the soil urease activity and soil water content compared with shallow till -age(P<0.05).Application of organic fertilizer could significantly increase the urease activity and soil water con-tent under deep tillage condition .In 0-20 cm and 20-40 cm soil layer,the urease activity of DOF treatment in-creased by 11.9%and 54.3%,respectively,and the soil water content of DOF increased by 4.67%and 4.49%, respectively ,compared with DCK .Deep tillage helped to increase the content of total nitrogen and total phosphorus in 20-40 cm soil layer ,while shallow tillage helped to increase the content of total nitrogen and total phosphorus in 0-20 cm soil layer .Application of organic fertilizer could increase the contents of total nitrogen and total phosphor-us in 0 -20 cm soil layer .The contents of total nitrogen and total phosphorus in SOF treatment increased by 36.24%and 5.54%,respectively,and the content of total nitrogen and total phosphorus in DOF treatment

  16. 华北高寒区多年保护性耕作对农田土壤容重的影响%Long-term Effects of Conservation Tillage on Soil Bulk Density in Cropping Zone of Cold Plateau in North China

    Institute of Scientific and Technical Information of China (English)

    王岩; 张静; 刘玉华

    2013-01-01

    In order to protect the soil, reduce wind erosion and ensure the production, explore the suitable conservation tillage model for the alpine area in North China, to provide a theoretical basis to the local crop production. Based on located experiment of different farming methods for 9 years in Zhangbei, the ministry of agriculture field station, and in 2007-2008, the author studied the effect of the no-tillage, reduced tillage and traditional tillage soil bulk density. The results showed that 3 types of farming methods at the seeding stage and harvesting stage both with the highest was no tillage and the lowest was traditional tillage, at the seeding stage the 0-10 cm and 10-20 cm soil bulk density of no-tillage, respectively were 1.65 g/cm3 and 1.81 g/cm3, with traditional tillage were 1.38 g/cm3 and 1.47 g/cm3, at harvesting stage there was no significant change. In cold plateau in North China, the soil bulk density of cropping zone had been influenced obviously by different tillage methods, the traditional tillage and reduced tillage could be a significant reduction in soil bulk density. With the bio-power effect of crop root growth, seeding stage and harvesting stage no tillage and reduced tillage in cropping zone soil bulk density was downward trend, and there was no significant change in traditional tillage.%为了在保护土壤、减抑风蚀的同时,兼顾作物的产量,探索适合华北高寒区的保护性耕作模式,给当地作物生产提供理论依据,在农业部张北野外观测站连续9年不同耕作方式定位研究的基础上,于2007-2009年探讨了免耕、松耕和翻耕对土壤耕层容重的影响.结果表明,3种耕作方式播种期不同耕层土壤容重均以免耕最高,翻耕最低,播前0~10 cm、10~20 cm土壤容重免耕分别为1.65、1.81 g/cm3,翻耕则分别为1.38、1.47 g/cm3,收获期土壤容重差异不明显.华北高寒区不同耕作方式对农田耕层土壤容重具有明显的影响,翻耕和松耕

  17. 麦稻轮作下耕作模式对土壤理化性质和作物产量的影响%Effects of tillage patterns on crop yields and soil physicochemical properties in wheat-rice rotation system

    Institute of Scientific and Technical Information of China (English)

    武际; 郭熙盛; 张祥明; 王允青; 许征宇; 鲁剑巍

    2012-01-01

    为了探明不同耕作模式对土壤理化性质和作物产量的影响,采用田间定位试验方法,于2007-2010连续4a在麦稻轮作制下开展了本试验研究.结果表明,免耕提高了耕层土壤体积质量,降低了土壤含水率.但是免耕土壤表层(0~10 cm)的体积质量仍在作物适宜生长的范围内,并未对作物的生长产生不利影响.免耕促进了土壤有机质和全氮在表层土壤的富集.0~10cm土层有机质和全氮含量比翻耕处理显著增加,而>10~20 cm土层上述养分含量明显低于翻耕处理.小麦季免耕土壤的碱解氮、速效磷和速效钾含量的变化趋势与有机质和全氮含量相似,而水稻季免耕处理整个耕层土壤碱解氮、速效磷和速效钾含量均低于翻耕处理.免耕显著的提高了小麦产量,但降低了水稻产量,起主要作用的产量构成因素是小麦和水稻的有效穗数.整个轮作周期的作物产量以小麦免耕水稻翻耕模式的产量较高,比小麦翻耕水稻免耕模式产量增加了5.70%.%In order to study effects of tillage systems on crop yields and soil physical and chemical properties in wheat-rice rotation system, a long term (2007-2010) experiment was conducted. The results showed that compared with conventional tillage, the soil bulk density increased and soil water content decreased with no-tillage. But even without tillage, bulk density of the 0-10 cm soil layer was still suitable for the growth of crops. No-tillage enriched soil organic matter and total nitrogen in the surface soil layer. Both the soil organic matter and total N content of no-tillage were significantly higher in 0-10 cm layer and lower in 10-20 cm layer than that of conventional tillage. During the wheat season, the soil alkali N, available P and available K contents had the same trends with those of organic matter and total N. Whereas during the rice season, with no-tillage, the soil alkali N、available P and available K contents

  18. Effect of green manure in soil quality and nitrogen transfer to cherry tomato in the no tillage system

    Science.gov (United States)

    Ambrosano, Edmilson; Rossi, Fabricio; Dias, Fabio; Trivelin, Paulo; Tavares, Silvio; Muraoka, Takashi; Ambrosano, Glaucia; Salgado, Gabriela; Otsuk, Ivani

    2016-04-01

    The use of alternative fertilizers may reduce costs and promote sustainability to the family-based agro ecological production system. The objective of this study was to quantify the contribution of the green manure to the quality of the soil and the transference of the nitrogen to cherry tomatoes using the N-15 abundance method (FAPESP 11/05648-3). The experiment was carried out in Piracicaba, APTA/SAA, SP, Brazil. The IAC collection accesses 21 of cherry tomatoes were used. Each Plot consisted of six plants spaced 0.5 m and 0.9 m between rows, using a randomized-blocks design with eight treatments and five repetitions. The treatments consisted of green manure crops intercropped or not with cherry tomato, namely: jack bean (Canavalia ensiformis), sunn hemp (Crotalaria juncea L.), velvet bean (Mucuna deeringiana), mung bean (Vigna radiata (L.) Wilczek), white lupine (Lupinus albus L.) and cowpea (Vigna unguiculata (L.) Walp). Besides two witnesses, one with and another without corn straw. Five leaves with petiole of each plant part from the first ripe fruit and a bunch of fruits per plant are harvested. Samples of leaf and fruit were weighed and dried in a forced air oven and its dry weight measured. A subsample was ground in a Wiley mill and brought to the mass spectrometer (ANCA GSL) on the Stable Isotopes Laboratory of CENA/USP for δN-15 analysis. It measured the percentage of the transference of N from the green manure to the tomato; the tomato plants grown in monocropping were considered a control. It was found that 27 % of the N present in the fruit and 23% of the N present in the leaves came from the green manure. These results show that dur¬ing the development of the fruit of the tomato there is a greater translocation and consequently, a higher use of the N from the green manure in the fruits than in the leaves. This production system can reduce the use of nitrogen fertilizers. The presence of a green manure in non-intercropped treatments caused some soil

  19. Zero Tillage cotton systems and soil quality

    Science.gov (United States)

    Landers, J. N.; de Freitas, P. L.

    2012-04-01

    Monocropping in cotton production systems negates the benefits of zero tillage. With cotton in a 3-year rotation including other summer and cover crops, such as soybeans and intensive-rooting Brachiaria spp., research on sandy soils in Bahia improved soil fertility, structure and biological activity. Cotton is a deep tap-rooted crop, sensitive to physical and chemical impediments to root development; this has engendered a paradigm of heavy soil preparation operations to remove these. But, ZT can overcome such obstacles, allowing the cotton crop to benefit from cost reductions and a number of other benefits, especially erosion control.. Soil quality has three principal dimensions. Maximum yields only occur when soil fertility, structure and biological activity are in balance. Under Zero Tillage management of Brazilian soils, the processes of nutrient availability, nutrient cycling and efficiency result from increasing SOM and higher CEC. ZT system fertility is also strongly influenced by total annual aerial and root biomass generation; C:N ratios of the biomass, changes in aeration in residue breakdown processes (for roots, dependent on internal drainage), reduced fixation of Phosphorus fertilizers, the possibility of surface application of P and K, use of deep-rooted cover crops to re-cycle nutrients and deleterious effects of over-liming. Soil physical parameters undergo a transformation : greater water holding capacity, a small increase in bulk density (ameliorated by a reversal of soil aggregate breakdown inherent to conventional tillage by the binding action of root exudates and fungal hyphae), enhanced particle aggregate size protects SOM from oxidation; old root holes create semi-permanent macro-pores which facilitate rooting, aeration and rainfall infiltration.. Soil life of all types benefits from ZT management and contributes to soil fertility and structural improvements, plus enhancing certain biological controls of pathogenic organisms and allelopathic

  20. Affects of different tillage managements on soil physical quality in a clayey soil.

    Science.gov (United States)

    Sağlam, Mustafa; Selvi, Kemal Çağatay; Dengiz, Orhan; Gürsoy, Fatma Esra

    2015-01-01

    This study, conducted in 2011, researches the effects of different tillage practices on the physical soil quality of clayey soil. This soil quality index (SQI) assessment was made by studying the changes in physical soil functions such as suitability for root development, facilitation for water entry, movement and storage, and resistance against surface degradation based on tillage management. When compared with the control parcel, statistically significant decreases were seen in the SQI with different tillage practices (p tillage practices, the highest SQI was seen with the plow + rotary tiller + direct seeding machine, while the lowest SQI was seen with the direct drilling practice. On the other hand, the statistically insignificant effects of tillage practices on the soil quality of the study area were considered to be a result of either the study period or the joint effect of soil texture and climatic features. Thus, long-term tillage practices were recommended in order to get healthier information about soil quality by considering soil and climatic conditions. In addition, for heavy clayey soils, reduced tillage practices, which included plowing, were thought to develop physical soil qualities of root development and water movement.

  1. Evaluation of Conservation Tillage Techniques for Maize Production ...

    African Journals Online (AJOL)

    2 International Maize and Wheat Improvement Center (CIMMYT), P.O. Box 5689, Addis Ababa, Ethiopia. አሕፅሮተ-ጥናት .... Previous studies have reported the impacts of CA on yield, soil and water productivity ..... American Society of Agronomy, Madison, pp. 29–43. ... Effect of different tillage systems on the quality and crop.

  2. Effects of Planting Density, Duration of Disclosing Plastic Film and Nitrogen Fertilization on the Growth Dynamics of Rapeseed under No-tillage Cultivation%不同密度·揭膜时间和施氮量对免耕油菜生育动态的影响

    Institute of Scientific and Technical Information of China (English)

    曾志三; 艾复清; 张一帆

    2009-01-01

    [Objective] This study was to understend the optimized combination of planting density, duration of disclosing plastic film and nitrogen fertilization under no-tillage cultivation. [Method] Quadratic polynomial regression and saturated D-optimal design were employed to investigate the effects of planting density, duration of disclosing plastic film and nitrogen fertilization on the dynamics growth of rapeseed under no-tillage cultivation. [Result] Within the experimental range, the growth dynamics of no-tillage cultivated rapeseed assumed a rise-fall tend. For the effects to the growth dynamics of no-tillage cultivated rapeseed, nitrogen application amount was higher than planting density and duration of disclosing plastic film. The interaction effect between planting density and duration of disclosing plastic film was higher than that between nitrogen application amount and planting density, and between nitrogen application amount and duration of disclosing plastic film. [Conclusion] The optimized combination of these factors for dynamic growth of rapeseed under no-tillage cultivation was determined to be: planting density of per hectare 154 925 individuals, duration of disclosing plastic film of 110 d, nitrogen application amount of 315 kg/hm2.

  3. Effects of Different Tillage on Soil Moisture and Temperature on Sloping Farmland in the Wind-water Erosion Crisscross Region%水蚀风蚀交错区坡耕地不同耕作措施水温效应研究

    Institute of Scientific and Technical Information of China (English)

    刘强; 冯永忠; 杨世琦; 廖允成; 杨改河

    2011-01-01

    Studying the effects of different tillage on soil moisture and temperature in sloping farmland will provide some effective tillage measures and the credible background for reasonable tillage usage in the wind-water erosion crisscross region. The methods of positioning monitoring and Statistics were served to study the effects of conventional tillage and five conservation tillage on soil moisture and temperature in sloping farmland of the wind-water erosion crisscross region. The result shows that, straw mulching(SM), no-tillage (NT) and plastic film mulching (PM) can significantly increased soil moisture in the surface layer, and soil moisture of the deeper layer is lower in NT and higher in SM. All of the conservation tillage can keep the suitable soil temperature at the stages of extremes. Based on soil moisture and temperature, all of the conservation tillage showed positive effects, and SM is better than the other tillage.%通过对坡耕地保护性耕作水温效应的研究,为水蚀风蚀交错区提供多种有效的耕作措施,并为当地农田采用合理的耕作措施提供依据.运用定位监测和数理统计的方法,研究黄土高原水蚀风蚀交错带坡耕地传统耕作与免耕、秸秆覆盖、地膜覆盖、起垄地膜覆盖、套种5种保护性耕作措施陡坡地的水温效应.结果表明,秸秆覆盖、免耕、地膜覆盖都能够显著提高表层水分含量,而深层免耕水分含量较低,秸秆覆盖水分含量较高;各保护性耕作都有在气温低时保温和在高温时降温的作用.各保护性耕作对水温有正效应,其中秸秆覆盖更优于其他保护性耕作.

  4. [Impact of tillage practices on microbial biomass carbon in top layer of black soils].

    Science.gov (United States)

    Sun, Bing-jie; Jia, Shu-xia; Zhang, Xiao-ping; Liang, Ai-zhen; Chen, Xue-wen; Zhang, Shi-xiu; Liu, Si-yi; Chen, Sheng-long

    2015-01-01

    A study was conducted on a long-term (13 years) tillage and rotation experiment on black soil in northeast China to determine the effects of tillage, time and soil depth on soil microbial biomass carbon (MBC). Tillage systems included no tillage (NT), ridge tillage (RT) and mould-board plough (MP). Soil sampling was done at 0-5, 5-10 and 10-20 cm depths in June, August and September, 2013, and April, 2014 in the corn phase of corn-soybean rotation plots. MBC content was measured by the chloroform fumigation extraction (CFE) method. The results showed that the MBC content varied with sampling time and soil depth. Soil MBC content was the lowest in April for all three tillage systems, and was highest in June for MP, and highest in August for NT and RT. At each sampling time, tillage system had a significant effect on soil MBC content only in the top 0-5 cm layer. The MBC content showed obvious stratification under NT and RT with a higher MBC content in the top 0-5 cm layer than under MP. The stratification ratios under NT and RT were greatest in September when they were respectively 67.8% and 95.5% greater than under MP. Our results showed that soil MBC contents were greatly affected by the time and soil depth, and were more apparently accumulated in the top layer under NT and RT.

  5. Conservation tillage affects species composition but not species diversity: a comparative study in Northern Italy.

    Science.gov (United States)

    Boscutti, Francesco; Sigura, Maurizia; Gambon, Nadia; Lagazio, Corrado; Krüsi, Bertil O; Bonfanti, Pierluigi

    2015-02-01

    Conservation tillage (CT) is widely considered to be a practice aimed at preserving several ecosystem functions. In the literature, however, there seems to be no clear pattern with regard to its benefits on species diversity and species composition. In Northern Italy, we compared species composition and diversity of both vascular plants and Carabids under two contrasting tillage systems, i.e., CT and conventional tillage, respectively. We hypothesized a significant positive impact of CT on both species diversity and composition. We also considered the potential influence of crop type. The tillage systems were studied under open field conditions with three types of annual crops (i.e., maize, soybean, and winter cereals), using a split-plot design on pairs of adjacent fields. Linear mixed models were applied to test tillage system, crop, and interaction effects on diversity indices. Plant and Carabids communities were analyzed by multivariate methods (CCA). On the whole, 136 plant and 51 carabid taxa were recorded. The two tillage systems studied did not differ in floristic or carabid diversity. Species composition, by contrast, proved to be characteristic for each combination of tillage system and crop type. In particular, CT fields were characterized by nutrient demanding weeds and the associated Carabids. The differences were especially pronounced in fields with winter cereals. The same was true for the flora and Carabids along the field boundaries. For studying the effects of CT practices on the sustainability of agro-ecosystems, therefore, the focus should be on species composition rather than on diversity measures.

  6. Improvement of native grassland by legumes introduction and tillage techniques

    OpenAIRE

    Syamsu Bahar; S. Hardjosoewignjo; I Kismono; O Haridjaja

    1999-01-01

    A factorial design using three species of legumes (Siratro, Centro and Stylo) and three different of tillage techniques (no-tillage, minimum tillage and total tillage) was applied in this experiment. The results showed that there was no interaction between species and tillage techniques. There was significant reductions on bulk density from 1.23±0.03 g/cm3 (no-tillage) to 1.07±0.02 g/cm3 (minimum tillage) and 1.05±0.03 g/cm3 (total tillage). Also reductions on penetration resistance from 17.4...

  7. Soil Tillage Systems and Wheat Yield under Climate Change Scenarios

    Directory of Open Access Journals (Sweden)

    Pieranna Servadio

    2016-09-01

    Full Text Available In this study, the effects of three different main preparatory tillage operations: ploughing at 0.4 m (P40 and 0.20 m (P20 depth and harrowing at 0.20 m depth (MT were investigated. The tillage operations were carried out at two different times, as the soil water content increased over time from rainfall: (low, 58% (LH and high, 80% (HH of field capacity. Results obtained from the soil monitoring carried out before and after tillage showed high values of soil strength in terms of Penetration resistance and shear strength particularly in deeper soil layers at lower water content. During tillage, fossil-fuel energy requirements for P40 LH and P20 LH were 25% and 35% higher, respectively, with respect to the HH treatments and tractor slip was very high (P40 LH = 32.4% with respect to the P40 HH treatment (16%. Soil water content significantly influenced tractor performance during soil ploughing at 0.40 m depth but no effect was observed for the MT treatment. The highly significant linear relations between grain yield and soil penetration resistance highlight how soil strength may be good indicator of soil productivity. We conclude that ploughing soil to a 0.20 m depth or harrowing soil to a 0.20 m depth is suitable for this type of soil under climate change scenarios.

  8. Tillage-induced short-term soil organic matter turnover and respiration

    Science.gov (United States)

    Fiedler, Sebastian Rainer; Leinweber, Peter; Jurasinski, Gerald; Eckhardt, Kai-Uwe; Glatzel, Stephan

    2016-09-01

    Tillage induces decomposition and mineralisation of soil organic matter (SOM) by the disruption of macroaggregates and may increase soil CO2 efflux by respiration, but these processes are not well understood at the molecular level. We sampled three treatments (mineral fertiliser: MF; biogas digestate: BD; unfertilised control: CL) of a Stagnic Luvisol a few hours before and directly after tillage as well as 4 days later from a harvested maize field in northern Germany and investigated these samples by means of pyrolysis-field ionisation mass spectrometry (Py-FIMS) and hot-water extraction. Before tillage, the Py-FIMS mass spectra revealed differences in relative ion intensities of MF and CL compared to BD most likely attributable to the cattle manure used for the biogas feedstock and to relative enrichments during anaerobic fermentation. After tillage, the CO2 effluxes were increased in all treatments, but this increase was less pronounced in BD. We explain this by restricted availability of readily biodegradable carbon compounds and possibly an inhibitory effect of sterols from digestates. Significant changes in SOM composition were observed following tillage. In particular, lignin decomposition and increased proportions of N-containing compounds were detected in BD. In MF, lipid proportions increased at the expense of ammonia, ammonium, carbohydrates and peptides, indicating enhanced microbial activity. SOM composition in CL was unaffected by tillage. Our analyses provide strong evidence for significant short-term SOM changes due to tillage in fertilised soils.

  9. 保护性耕作对绿洲灌区冬小麦产量形成的影响%Effect of Conservation Tillage on Dry Matter Accumulating and Yield of Winter Wheat in Oasis Area

    Institute of Scientific and Technical Information of China (English)

    李玲玲; 黄高宝; 秦舒浩; 于爱忠

    2011-01-01

    Hexi Oasis is the most important region for food crop production in Gansu province, where is not only exposed to serious wind erosion but also one of the main sources of dust storm in China. Spring wheat traditionally dominates in wheat production in this region, but the bare field from dry winter to spring usually accelerates serious wind erosion. Conservation tillage proves to be able to increase water use efficiency (WUE) and eliminate soil erosion. In this study, dry matter accumulating, yield and WUE of winter wheat under different tillage practices were investigated in order to establish proper systems of conservation tillage in the Hexi Oasis area for winter wheat production, and to save water and prevent wind erosion. Experiments on five tillage practices were carried out from 2004 to 2007, including conventional tillage (T), conventional tillage with stubble incorporated (TIS), no-tillage (NT), no-tillage with stubble retention (NTS), and no-tillage with stubble standing (NTSS). The effects of conservation tillage on dry matter dynamics, grain-filling characteristics, grain yield, yield components, and WUE of winter wheat were determined using wheat cultivar Fan-13. Compared with treatment T, the growth and development process and grain-filling duration of winter wheat were prolonged in NTS and NTSS treatments. Both treatments had higher values in dry matter, relative growth rate (RGR), grain-filling duration, average filling velocity in spike of main stem, and filling index than other treatments.Although the grain number per spike and 1000-grain weight of NTS and NTSS varied across years, they generally showed higher levels than those of the T and TIS treatments, especially the NTSS treatment. The highest WUE was observed in the NTS treatment. The average grain yields (2004-2007) of NTS and NTSS were increased by 18.6% and 23.8% compared to the T treatment,and the average WUE (2005-2007) of NTS and NTSS were enhanced by 26.8% and 16.1

  10. 保护性耕作对农田土壤有机碳及农业生产力的影响%Effects of Conservation Tillage on Soil Organic Carbon and Agricultural Productivity

    Institute of Scientific and Technical Information of China (English)

    王岩松; 李梦迪; 朱连奇

    2016-01-01

    Farmland soil organic carbon pool is the carbon pool affected by human mostly, its recovery has important significance on soil quality enhancement, food security guarantee, water conservation and CO2 emission decrease. Conservation tillage has significant effect on the decrease of water and soil loss, the increase of soil organic carbon and the increase of crop yield. The authors summarized the influence of conservation tillage on soil organic carbon and soil physical and chemical properties, discussed its effect on agricultural productivity, put forward improvement suggestions based on the problems existing in the conservation tillage, and provided scientific basis for reasonable cultivation measures and agricultural management.%农田土壤有机碳库作为陆地生态系统中受人类影响最大的碳库,其恢复对于增强土壤质量,保障粮食安全,涵养水源,减少大气CO2排放具有重要意义.保护性耕作对减少水土流失,增加土壤有机碳、增加农作物产量等方面有显著效果.笔者综述了保护性耕作对农田土壤有机碳及土壤理化性质的影响,探讨了保护性耕作对农业生产力的影响,对保护性耕作存在的问题提出了改进建议,为合理制订耕作措施和农业生产管理措施提供了科学依据.

  11. Variations in thematic mapper spectra of soil related to tillage and crop residue management - Initial evaluation

    Science.gov (United States)

    Seeley, M. W.; Ruschy, D. L.; Linden, D. R.

    1983-01-01

    A cooperative research project was initiated in 1982 to study differences in thematic mapper spectral characteristics caused by variable tillage and crop residue practices. Initial evaluations of radiometric data suggest that spectral separability of variably tilled soils can be confounded by moisture and weathering effects. Separability of bare tilled soils from those with significant amounts of corn residue is enhanced by wet conditions, but still possible under dry conditions when recent tillage operations have occurred. In addition, thematic mapper data may provide an alternative method to study the radiant energy balance at the soil surface in conjunction with variable tillage systems.

  12. PORE SIZE DISTRIBUTION AND SOIL HYDRO PHYSICAL PROPERTIES UNDER DIFFERENT TILLAGE PRACTICES AND COVER CROPS IN A TYPIC HAPLUSULT IN NORTHERN NIGERIA

    Directory of Open Access Journals (Sweden)

    Halima Mohammed Lawal

    2017-05-01

    Full Text Available Tillage practices influence soil physical, chemical and biological qualities which in-turn alters plant growth and crop yield. In the Northern Guinea Savanna (NGS ecological zone of Nigeria, agricultural production is mainly constrained by low soil nutrient and water holding capacity, it is therefore, imperative to develop appropriate management practices that will give optimal soil hydro-physical properties for proper plant growth, effective soil and water management and environmental conservation. This study investigated the effect of three tillage practices (no till, reduced till and conventional till and four cover crops (Centrosema pascuorum, Macrotyloma uniflorum, Cucurbita maxima and Glyine max and a bare/control (no cover crop on some soil physical properties of a Typic Haplusult during the rainy seasons of 2011, 2012 and 2013 in Samaru, NGS ecological zone of Nigeria. The field trials were laid out in a split plot arrangement with tillage practices in the main plots and cover crops in the subplots, all treatments were replicated three times. Auger and core soil samples were collected at the end of each cropping season each year in three replicates from each treatment plot at four depths (0-5, 5-10, 10-15 and 15-20 cm. Particle size distribution, bulk density, total pore volume and water retention at various soil matric potentials were determined using standard methods. Data obtained were compared with optimum values and fitted into a RETC computer code for quantifying soil hydraulic behavior and physical quality. Results showed that different tillage practices had varied effect on soil physical properties. No-till had the highest water holding capacity at most suction points evaluated, it had 4.3 % and 12.9 % more soil moisture than the reduced till  and conventionally tilled systems across all matric potentials while Centrosema pascuorum (3.1% and Cucurbita maxima (5.5% were best among evaluated cover crops in retaining soil moisture

  13. Response of Wheat to Tillage Plus Rice Residue and Nitrogen Management in Rice-Wheat System

    Institute of Scientific and Technical Information of China (English)

    Khalid Usman; Ejaz Ahmad Khan; Niamatullah Khan; Abdur Rashid; Fazal Yazdan; Saleem Ud Din

    2014-01-01

    Zero tillage with residues retention and optimizing nitrogen fertilization are important strategies to improve soil quality and wheat (Triticum aestivum L.) yield in rice (Oryza sativa L.)-wheat system. Field experiments were conducted on silty clay soil (Hyperthermic, and Typic Torrilfuvents) in D. I. Khan, Pakistan, to explore the impact of six tillage methods (zero tillage straw retained (ZTsr), ZT straw burnt (ZTsb), reduced tillage straw incorporated (RTsi, including tiller and rotavator), RT straw burnt (RTsb), conventional tillage straw incorporated (CTsi, including disc plow, tiller, rotavator, and leveling operations), CT straw burnt (CTsb)) and ifve nitrogen rates, i.e., 0, 100, 150, 200, and 250 kg ha-1 on wheat yield. Mean values for N revealed that spikes m-2, grains/spike, 1 000-grain weight (g), and grain yield (kg ha-1) were signiifcantly higher at 200 kg N ha-1 in both the years as well as mean over years than all other treatments. Mean values for tillage revealed that ZTsr produced highest number of spikes m-2 among tillage methods. However, grains/spike, 1 000-grain weight, and grain yield were higher in tillage methods with either straw retained/incorporated than tillage methods with straw burnt. Interaction effects were signiifcant in year 1 and in mean over years regarding spikes m-2, 1 000-grain weight, total soil organic matter (SOM), and total soil N (TSN). ZTsr produced the most spikes m-2 and 1 000-grain weight at 200 kg N ha-1. ZTsr also produced higher SOM and TSN at 200-250 kg N ha-1 at the end of 2 yr cropping. Thus ZTsr with 200 kg N ha-1 may be an optimum and sustainable approach to enhance wheat yield and soil quality in rice-wheat system.

  14. Effects of no-tillage and stubble-remaining on soil enzyme activities in broadcasting rice seedlings paddy field%免耕与秸秆高留茬还田对抛秧稻田土壤酶活性的影响

    Institute of Scientific and Technical Information of China (English)

    任万军; 黄云; 吴锦秀; 刘代银; 杨文钰

    2011-01-01

    A field experiment was conducted to study the effects of four cultivation modes ( conventional tillage, no-tillage, conventional tillage + stubble-remaining, and no-tillage + stubble-remaining) on the activities of urease, acid phosphatase, protease, and cellulose in different soil layers in a broadcasting rice seedlings paddy field. Under the four cultivation modes, the activities of test enzymes were higher in upper than in deeper soil layers, and had a greater difference between the soil layers under no-tillage + stubble-remaining. In upper soil layers, the activities of test enzymes were higher in the treatments of no-tillage than in the treatments of conventional tillage, being the highest under no-tillage + stubble-remaining and the lowest under conventional tillage. In deeper soil layers, the test enzyme activities were the highest under conventional tillage + stubble-remaining, followed by no-tillage + stubble-remaining, no-tillage, and conventional tillage. During the growth period of rice, soil urease and cellulose activities were lower at tillering stage, increased to the maximum at booting stage, and decreased then, soil acid phosphatase activity was higher at tillering stage but lower at elongating stage, whereas soil protease activity peaked at tillering and heading stages.%利用大田试验,研究了免耕+秸秆还田、免耕、常耕+秸秆还田、常耕4种耕作方式对稻田土壤剖面不同层次土壤酶活性的影响.结果表明:4种耕作方式的酶活性在土壤剖面上表现为上层高于下层,其中免耕+秸秆处理上、下土层间的差异大于其他处理.上层土壤的脲酶、酸性磷酸酶、蛋白酶和纤维素酶活性为免耕处理大干常耕处理,有秸秆还田处理大干无秸秆还田处理,以免耕+秸秆处理最高,常耕处理最低;下层土壤4种酶活性以常耕+秸秆处理最高,免耕+秸秆处理次之,免耕和常耕处理较低.水稻不同生育时期,脲酶和纤维素酶活性在

  15. 稻草还田免耕抛秧对水稻土剖面形态特征的影响%Effects of No-tillage and Rice-seedling Throwing with Rice Straw Returning to Paddy Soil on Profile Morphological Characteristics

    Institute of Scientific and Technical Information of China (English)

    黄景; 顾明华; 徐世宏; 杨为芳; 江立庚

    2012-01-01

    为探讨免耕抛秧栽培对土壤剖面形态特征的影响,分别对连续2年和7年结合稻草还田的常耕和免耕试验的土壤剖面进行了研究.结果表明,常耕对土壤剖面形态特征影响不明显.免耕改变了耕作层亚层的剖面形态特征,且表层土壤疏松和pH位变小;水稻根系向土壤表层集中和裂隙出现部位增高.普通免耕形成的耕作层构型是Aa1-Aa2-Aa3,疏松表层较薄、亚表层有变坚实的趋势.稻草还田免耕形成的耕作层构型是O-Aa1 -Aa2-Aa3,鳝血斑的数量增加、土壤颜色加深、疏松和体积质量降低.以稻草还田免耕抛秧形成的土壤剖面协调土壤肥力效果最好.%The effect of no-tillage with rice-seedling throwing on profile morphology was investigated by comparison of conventional tillage and no-tillage lasted two and seven years. The results showed that conventional tillage with rice-seedling throwing did not significantly affect morphology, but no-tillage with rice-seedling throwing formed new morphology of sub-plough-layer. The upper layers in no-tillage treatments became looser, more acidic and blacker compared with conventional tillage. The rice roots were concentrated in the surface layer and the location of fissures was raised in the plough layers in the no-tillage treatments. The plough layer solun constitutions of no-tillage without rice straw returning to paddy soils was Aal- Aa2- Aa3, while that of no-tillage with rice straw returning to paddy soils was O-Aal- Aa2- Aa3. The no-tillage with rice straw returning to paddy soil reduced soil density and had more iron-humus mottling, blacker and looser plough layers, but the no-tillage without rice straw returning to paddy soils tended to have solid sub-layer and thinner upper layer. Thus the profile fonned by no-tillage with rice straw returning to paddy soils is the best to coordinate soil fertility.

  16. Quantifying Update Effects in Citizen-Oriented Software

    Directory of Open Access Journals (Sweden)

    Ion Ivan

    2009-02-01

    Full Text Available Defining citizen-oriented software. Detailing technical issues regarding update process in this kind of software. Presenting different effects triggered by types of update. Building model for update costs estimation, including producer-side and consumer-side effects. Analyzing model applicability on INVMAT – large scale matrix inversion software. Proposing a model for update effects estimation. Specifying ways for softening effects of inaccurate updates.

  17. 保护性耕作对小麦-土壤系统综合效应研究%COMPREHENSIVE EFFECTS OF CONSERVATION TILLAGE ON WHEAT-SOIL SYSTEM

    Institute of Scientific and Technical Information of China (English)

    张水清; 黄绍敏; 聂胜委; 郭斗斗; 程秀洲

    2012-01-01

    Combination of long-term(18 years at Zhengzhou) and short-term(2 years at Yanling) field experiment,chemical analysis and data statistics were employed to study comprehensive effects of conservation tillage on wheat-soil system.The results showed that compared with traditional tillage,conservation tillage significantly increased soil organic matter,alkali-hydrolyzable nitrogen,available phosphorus and exchangeable potassium.However,there was no significant difference in wheat(Triticum aestivum L.) grain yield between the two tillage patterns.The spike number and grain number per spike of wheat in no tillage(NT) and shallow tillage(ST) treatments were more than those in rotary tillage(RT) and deep tillage(DT) treatments,while there was no significant difference in 1000-grains weight and grain yield of wheat among the four tillage patterns.In treatments of NT and ST,soil water content,alkali-hydrolyzable nitrogen,available phosphorus,were enhanced,especially for soil microbial biomass C and N.Therefore,in Henan province NT and ST is the better conservation tillage pattern for wheat production and soil continuous use.%采用长期定位试验与短期田间试验相结合的方法,通过室内化验分析和数理统计,研究了河南省不同土壤类型区保护性耕作对土壤理化性质、土壤微生物生物量碳氮及小麦(Triticum aestivum L.)籽粒产量和产量构成因素的影响。结果表明,与传统耕作相比,保护性耕作显著提高土壤有机质、碱解氮、有效磷及交换性钾含量,分别提高24.8%、14.3%、7.8%和24.8%;而对小麦增产效果并不显著。4种不同保护性耕作方式下,免耕、浅耕相比旋耕、深耕,提高小麦穗数15.0%~32.2%,提高穗粒数2.6%~12.6%,但4种处理间小麦千粒重及籽粒产量效果无显著差异;免耕、浅耕较旋耕、深耕可以一定程度上提高苗期和灌浆期土壤含水率、以及土壤碱解氮和有效磷,并显著提

  18. Experimental analysis of CO₂ emissions from agricultural soils subjected to five different tillage systems in Lithuania.

    Science.gov (United States)

    Buragienė, Sidona; Šarauskis, Egidijus; Romaneckas, Kęstutis; Sasnauskienė, Jurgita; Masilionytė, Laura; Kriaučiūnienė, Zita

    2015-05-01

    Intensive agricultural production strongly influences the global processes that determine climate change. Thus, tillage can play a very important role in climate change. The intensity of soil carbon dioxide (CO₂) emissions, which contribute to the greenhouse effect, can vary depending on the following factors: the tillage system used, meteorological conditions (which vary in different regions of the world), soil properties, plant residue characteristics and other factors. The main purpose of this research was to analyse and assess the effects of autumn tillage systems with different intensities on CO₂ emissions from soils during different seasons and under the climatic conditions of Central Lithuania. The research was conducted at the Experimental Station of Aleksandras Stulginskis University from 2009 to 2012; and in 2014. The soils at the experimental site were classified as Eutric Endogleyic Planosol (Drainic). The investigations were conducted using five tillage systems with different intensities, typical of the Baltic Region. Deep conventional ploughing was performed at a depth of 230-250 mm, shallow ploughing was conducted at a depth of 120-150 mm, deep loosening was conducted at depths of 250-270 mm, and shallow loosening was conducted at depths of 120-150 mm. The fifth system was a no-tillage system. Overall, autumn tillage resulted in greater CO₂ emissions from the soil over both short- and long-term periods under the climatic conditions of Central Lithuania, regardless of the tillage system applied. The highest soil CO₂ emissions were observed for the conventional deep ploughing tillage system, and the lowest emissions were observed for the no-tillage system. The meteorological conditions greatly influenced the CO₂ emissions from the soil during the spring. Soil CO₂ emissions were enhanced as precipitation and the air and soil temperatures increased. Long-term investigations regarding the dynamics of CO₂ emissions from soils during the maize

  19. Effects of No-Tillage and Rice-Seedling Casting with Rice Straw Returning on Content of Nitrogen, Phosphorus and Potassium of Soil Profiles%稻草还田免耕抛秧对土壤剖面氮、磷、钾含量的影响

    Institute of Scientific and Technical Information of China (English)

    黄景; 顾明华; 徐世宏; 杨为芳; 江立庚

    2012-01-01

    [Objective] The objective of this study was to understand the effects of no-tillage and rice-seedling casting with rice straw returning on nitrogen, phosphorus and potassium of paddy soil profile. [Method] Contents of nitrogen, phosphorus and potassium of paddy soil profile soil of conventional tillage of rice-seedling casting and no-tillage of rice-seedling casting experiments that lasted two and seven years were investigated. [Result] Contents of total nitrogen, total phosphorus, alkaline-hydrolysable nitrogen and rapidly available phosphorus in 0-4(5) cm soil layer of no-tillage treatments were higher than those of conventional tillage. Contents of total potassium in 0-4(5) cm soil layer of no-tillage with rice straw returning treatment were significantly higher than those of common conventional tillage. Contents of rapidly available potassium in 0-4(5) cm soil layer of no-tillage with rice straw returning treatment were lower than that of conventional tillage with rice straw returning, but significantly higher than that of common conventional tillage. Contents of total nitrogen, total phosphorus, total potassium, alkaline-hydrolysable nitrogen and rapidly available phosphorus in 5-20 cm soil layer of no-tillage treatments were lower than those of conventional tillage. Content of rapidly available potassium in Aa layer (cultivation layer) of common no-tillage treatment was lower than those of conventional tillage. Contents of alkaline-hydrolysable nitrogen and rapidly available potassium in Ap layer (plow pan), W layer (waterlogged layer) and C layer (parent material layer) were higher than those of conventional tillage. [Conclusion] The effects of no-tillage of rice-seedling casting with of rice straw returning on coordinate soil nitrogen, phosphorus and potassium are superior to that of common no-tillage of rice-seedling casting, and no-tillage of rice-seedling casting with rice straw returning is advantageous to the improvement and development of soil

  20. Efeitos de sistemas de preparo nas propriedades físicas de um Latossolo Vermelho distrófico Effects of tillage systems on the soil physical properties of a dystrophic Red Latosol

    Directory of Open Access Journals (Sweden)

    Karina Maria Vieira Cavalieri

    2006-02-01

    residue management are essential for the sustainability of cassava production in sandy and sandy loam soils of Northwestern Paraná State, Southern Brazil. The objective of this study was to evaluate the effects of different tillage systems used for planting cassava: no-tillage (NT, minimum tillage using chiseling (MT and conventional tillage with moldboard plow and disking (CT on some physical properties of a dystrophic Red Latosol. The following soil physical properties were evaluated in the 0-0.15 m and 0.15-0.30 m soil layers: soil bulk density (BD, soil water retention curve, soil resistance to penetration curve and least limiting water range (LLWR. Higher values of BD and soil resistance to penetration were verified in the NT and MT treatments. The soil water retention curve was only influenced by BD, which incorporated the effects of the soil tillage systems independent of sampled layers. The soil resistance curve to penetration was influenced by tillage systems and layers, indicating that the soil resistance to root penetration was higher in NT > MT > CT, and was accentuated at the 0.15-0.30 m depth. The increase in the BD led to a reduction in the LLWR due to the effects of soil resistance to penetration and air-filled porosity, which in turn determined the range of soil available water. Results indicated that LLWR value followed the sequence: PC = PM > PSR in the 0-0.15 m soil layer, and was not influenced by tillage systems in the 0.15-0.30 soil layer The critical bulk density value (BDc, the BD value at which LLWR = 0, was lower in NT and MT tillage systems compared with CT, therefore resulting in a smaller frequency of higher BD values than BDc in the soil under CT.

  1. QUANTIFYING OBSERVATIONAL PROJECTION EFFECTS USING MOLECULAR CLOUD SIMULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Beaumont, Christopher N. [Institute for Astronomy, University of Hawai' i, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Offner, Stella S.R. [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Shetty, Rahul; Glover, Simon C. O. [Zentrum für Astronomie der Universität Heidelberg, Institut für Theoretische Astrophysik, Albert-Ueberle-Str. 2, D-69120 Heidelberg (Germany); Goodman, Alyssa A., E-mail: beaumont@ifa.hawaii.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)

    2013-11-10

    The physical properties of molecular clouds are often measured using spectral-line observations, which provide the only probes of the clouds' velocity structure. It is hard, though, to assess whether and to what extent intensity features in position-position-velocity (PPV) space correspond to 'real' density structures in position-position-position (PPP) space. In this paper, we create synthetic molecular cloud spectral-line maps of simulated molecular clouds, and present a new technique for measuring the reality of individual PPV structures. Using a dendrogram algorithm, we identify hierarchical structures in both PPP and PPV space. Our procedure projects density structures identified in PPP space into corresponding intensity structures in PPV space and then measures the geometric overlap of the projected structures with structures identified from the synthetic observation. The fractional overlap between a PPP and PPV structure quantifies how well the synthetic observation recovers information about the three-dimensional structure. Applying this machinery to a set of synthetic observations of CO isotopes, we measure how well spectral-line measurements recover mass, size, velocity dispersion, and virial parameter for a simulated star-forming region. By disabling various steps of our analysis, we investigate how much opacity, chemistry, and gravity affect measurements of physical properties extracted from PPV cubes. For the simulations used here, which offer a decent, but not perfect, match to the properties of a star-forming region like Perseus, our results suggest that superposition induces a ∼40% uncertainty in masses, sizes, and velocity dispersions derived from {sup 13}CO (J = 1-0). As would be expected, superposition and confusion is worst in regions where the filling factor of emitting material is large. The virial parameter is most affected by superposition, such that estimates of the virial parameter derived from PPV and PPP information

  2. Study of electrokinetic effects to quantify groundwater flow

    Energy Technology Data Exchange (ETDEWEB)

    Brown, S.R. [Sandia National Lab., Albuquerque, NM (United States); Haupt, R.W. [MIT Lincoln Lab., Lexington, MA (United States)

    1997-04-01

    An experimental study of electrokinetic effects (streaming potential) in earth materials was undertaken. The objective was to evaluate the measurement of electrokinetic effects as a method of monitoring and predicting the movement of groundwater, contaminant plumes, and other fluids in the subsurface. The laboratory experiments verified that the electrokinetic effects in earth materials are prominent, repeatable, and can be described well to first order by a pair of coupled differential equations.

  3. Effects of different rotational tillage patterns on soil physical properties and yield of winter wheat-spring maize rotation field in Weibei highland%不同轮耕方式对渭北旱塬麦玉轮作田土壤物理性状与产量的影响

    Institute of Scientific and Technical Information of China (English)

    陈宁宁; 李军; 吕薇; 王淑兰

    2015-01-01

    To study the effects of different rotational tillage patterns on soil physical properties and crop yield under winter wheat-spring maize single-cropping rotation systems in Weibei highlands, a 7-year on-site conservation tillage experiment was conducted, which consisted of three rotational tillage and three continuous tillage treatments. The rotational tillage systems included NT/ST (yearly rotation between no-tillage and subsoiling), ST/CT (yearly rotation between subsoiling and conventional tillage) and CT/NT (yearly rotation between conventional tillage and no-tillage). Also the continuous tillage treatments included continuous no-tillage (NT/NT), continuous subsoiling (ST/ST) and continuous conventional tillage (CT/CT). The study was conducted in wheat-maize rotation fields in 2007 to 2014 in Heyang County, Shaanxi Province. Soil physical properties (e.g., bulk density, soil aggregates and soil moisture) and crop yield under different tillage treatments were measured in 2014. The results were as follows: 1) Soil bulk density, soil porosity and field water capacity were significantly impacted by the three rotational tillage patterns, and were best under NT/ST rotational tillage. Compared with CT/CT treatment, NT/ST rotational tillage treatment increased average field capacity in the 0-60 cm soil layer by 12.9%. 2) The properties of soil aggregates changed significantly under different rotational tillage treatments. The NT/ST treatment was the best with the highest macro-aggregate content (R0.25), lowest rate of structure break-up, lowest unstable aggregate index (ELT), highest water-stable aggregate mean weight diameter (MWD) and lowest fractal dimension (D) of mechanical-stable and water-stable aggregates. 3) In wheat growing period, average soil water storage in the 0-200 cm soil layer and yield of wheat under NT/ST treatment were respectively 17.7 mm and 9.5% higher than CT/CT treatment. It was concluded that rotational tillage was conducive for improving

  4. [Effect of long-term shallow tillage and straw returning on soil potassium content and stratification ratio in winter wheat/summer maize rotation system in Guanzhong Plain, Northwest China].

    Science.gov (United States)

    Shi, Jiang-lan; Li, Xiu-shuang; Wang, Shu-juan; Li, Shuo; Li, You-bing; Tian, Xiao-hong

    2015-11-01

    Soil stratified sampling method and potassium chemical fractionation analysis were used to investigate effects of long-term shallow tillage and straw returning on soil K contents and stratification ratios in winter wheat/summer maize rotation system in Guanzhong Plain of Northwest China. The results showed that after 13-year continuous shallow tillage and straw returning, surface accumulation and stratification effect obviously occurred for soil available K (SAK) and non-exchangeable K (NEK), which was particularly remarkable for SAK and its fractions. Serious depletion of SAK occurred in 15-30 cm soil layer, and the SAK value was lower than the critical value of soil potassium deficiency. Meanwhile, significant differences were found between SR1 and SR2 values of SAK and its fractions, SR was obtained by values of topsoil layer (0-5 cm) divided by corresponding values of lower soil layers (5-15 cm layer, SR1, or 15-30 cm layer, SR2). However, no significant difference was observed between SR values of NEK and mineral K. In conclusion, returning of all straw over 10 years in the winter wheat/summer maize rotation system contributed greatly to maintaining soil K pool balance, while special attention should be paid to the negative effects of surface accumulation and stratification of SAK on soil K fertility.

  5. Reduced greenhouse gas mitigation potential of no-tillage soils through earthworm activity.

    Science.gov (United States)

    Lubbers, Ingrid M; van Groenigen, Kees Jan; Brussaard, Lijbert; van Groenigen, Jan Willem

    2015-09-04

    Concerns about rising greenhouse gas (GHG) concentrations have spurred the promotion of no-tillage practices as a means to stimulate carbon storage and reduce CO2 emissions in agro-ecosystems. Recent research has ignited debate about the effect of earthworms on the GHG balance of soil. It is unclear how earthworms interact with soil management practices, making long-term predictions on their effect in agro-ecosystems problematic. Here we show, in a unique two-year experiment, that earthworm presence increases the combined cumulative emissions of CO2 and N2O from a simulated no-tillage (NT) system to the same level as a simulated conventional tillage (CT) system. We found no evidence for increased soil C storage in the presence of earthworms. Because NT agriculture stimulates earthworm presence, our results identify a possible biological pathway for the limited potential of no-tillage soils with respect to GHG mitigation.

  6. Soil organic carbon sequestration and tillage systems in Mediterranean environments

    Science.gov (United States)

    Francaviglia, Rosa; Di Bene, Claudia; Marchetti, Alessandro; Farina, Roberta

    2016-04-01

    Soil carbon sequestration is of special interest in Mediterranean areas, where rainfed cropping systems are prevalent, inputs of organic matter to soils are low and mostly rely on crop residues, while losses are high due to climatic and anthropic factors such as intensive and non-conservative farming practices. The adoption of reduced or no tillage systems, characterized by a lower soil disturbance in comparison with conventional tillage, has proved to be positively effective on soil organic carbon (SOC) conservation and other physical and chemical processes, parameters or functions, e.g. erosion, compaction, ion retention and exchange, buffering capacity, water retention and aggregate stability. Moreover, soil biological and biochemical processes are usually improved by the reduction of tillage intensity. The work deals with some results available in the scientific literature, and related to field experiment on arable crops performed in Italy, Greece, Morocco and Spain. Data were organized in a dataset containing the main environmental parameters (altitude, temperature, rainfall), soil tillage system information (conventional, minimum and no-tillage), soil parameters (bulk density, pH, particle size distribution and texture), crop type, rotation, management and length of the experiment in years, initial SOCi and final SOCf stocks. Sampling sites are located between 33° 00' and 43° 32' latitude N, 2-860 m a.s.l., with mean annual temperature and rainfall in the range 10.9-19.6° C and 355-900 mm. SOC data, expressed in t C ha-1, have been evaluated both in terms of Carbon Sequestration Rate, given by [(SOCf-SOCi)/length in years], and as percentage change in comparison with the initial value [(SOCf-SOCi)/SOCi*100]. Data variability due to the different environmental, soil and crop management conditions that influence SOC sequestration and losses will be examined.

  7. Evaluation and Comparison of Different Tillage Methods in Improvement of Salt-affected Soils in Wheat Production

    Directory of Open Access Journals (Sweden)

    M Roozbeh

    2015-07-01

    Full Text Available One of the main strategy for controlling salt-affected soils is to implement proper tillage method. A field experiments was conducted to determine the effect of different tillage methods on salt distribution and wheat yield in saline-sodic soil. The experiment was laid out according to randomized complete block design with three replications. Treatments were studied in the experiment including conventional tillage (T1, reduced tillage (T2, subsoiling+ conventional tillage (T3, subsoiling+reduced tillage (T4, subsoiling+power harrow (T5 and plowing without moldboard (T6. Electrical conductivity (EC Ph of the soil sodium adsorption ratio (SAR and cone index (CI were measured for all treatments. The results showed that the T3 and T4 treatments compared to T1, caused a significant salinity reduction by 17.8 and 10.3%, respectively. The SAR was influenced by different tillage systems. The maximum SAR was observed for T1 system and T2 relative to T1 system reduced SAR by 4.1%. The results also revealed that SAR in T3 system was significantly less than T1 (23.4% and T2 (20.1% systems. Different tillage systems had significant effects on wheat yield.

  8. Quantifying Effects of Voids in Woven Ceramic Matrix Composites

    Science.gov (United States)

    Goldsmith, Marlana B.; Sankar, Bhavani V.; Haftka, Raphael T.; Goldberg, Robert K.

    2013-01-01

    Randomness in woven ceramic matrix composite architecture has been found to cause large variability in stiffness and strength. The inherent voids are an aspect of the architecture that may cause a significant portion of the variability. A study is undertaken to investigate the effects of many voids of random sizes and distributions. Response surface approximations were formulated based on void parameters such as area and length fractions to provide an estimate of the effective stiffness. Obtaining quantitative relationships between the properties of the voids and their effects on stiffness of ceramic matrix composites are of ultimate interest, but the exploratory study presented here starts by first modeling the effects of voids on an isotropic material. Several cases with varying void parameters were modeled which resulted in a large amount of variability of the transverse stiffness and out-of-plane shear stiffness. An investigation into a physical explanation for the stiffness degradation led to the observation that the voids need to be treated as an entity that reduces load bearing capabilities in a space larger than what the void directly occupies through a corrected length fraction or area fraction. This provides explanation as to why void volume fraction is not the only important factor to consider when computing loss of stiffness.

  9. Flooding of tunnels: Quantifying climate change effects on infrastructure

    NARCIS (Netherlands)

    Huibregtse, J.N.; Napoles, O.M.; Dewit, M.S.

    2013-01-01

    To develop climate proof road infrastructure it is of importance to understand the quantitative effects of expected climate change on the performance of individual components, such as tunnels and road sections, and their contributions to the performance of the overall road network.A full understandi

  10. 保护性耕作对黄土高原春玉米田土壤理化特性的影响%Effects of conservation tillage on soil physicochemical properties in the spring maize area of the Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    刘鹏涛; 冯佰利; 慕芳; 苏旺; 徐芦; 蔡晓青; 刘月仙; 朱瑞祥; 薛少平

    2009-01-01

    为了探索黄土高原春玉米区保护性耕作农田土壤理化特性变化,测定分析了保护性耕作处理第二年春玉米生长不同时期农田土壤容重、水分和养分变化.结果表明,保护性耕作处理在玉米生长前期0~10 cm土壤容重呈下降趋势且小于传统耕作,但后期增加幅度较大;与传统耕作相比保护性耕作能显著增加玉米生长前期表层0~60 cm和后期100~200 cm土壤含水量 ,有较好保水、蓄水作用;保护性耕作下表层0~20 cm土壤养分指标除全磷外,均表现为稳定升高趋势,且能有效提高土壤全钾和速效钾含量;土壤有机质、全氮、速效氮、速效磷含量低于传统耕作,但变异系数较小.%The values of soil bulk density, water content and seven kinds of soil nutrie nt content (organic matter, total nitrogen, available nitrogen, total phosphorus , available phosphorus, total potassium and available potassium) were evaluated in an agricultural soil, located in the spring maize area of the Loess Plateau, with three treatments such as no tillage(NT), conventional tillage+straw retu rning(TS) and conventional tillage(CT), in order to study the effects of conse rvation tillage on the changes of physical and chemical properties of soil in th is zone. Samples were collected during the second year from the arable layer and four different stages. The results showed that the soil bulk density in the 0~ 10 cm soil depth under the treatment of no tillage was lower than that under con ventional tillage in prophase of maize growth, but had a larger increase in the later growing stage; compared to conventional tillage, no tillage made a signifi cant increase in soil water of 0~60 cm soil depth in the prophase of maize g rowth and 100~200 cm soil depth in the dough stage, and had a better effect on water storage; the contents of organic matter, total nitrogen, available nitroge n and available phosphorus in soil depth of 0~20 cm under

  11. Quantifying the effectiveness of early warning systems for natural hazards

    Directory of Open Access Journals (Sweden)

    M. Sättele

    2015-07-01

    Full Text Available Early warning systems (EWS are increasingly applied as preventive measures within an integrated risk management approach for natural hazards. At present, common standards and detailed guidelines for the evaluation of their effectiveness are lacking. To support decision-makers in the identification of optimal risk mitigation measures, a three-step framework approach for the evaluation of EWS is presented. The effectiveness is calculated in function of the technical and the inherent reliability of the EWS. The framework is applicable to automated and non-automated EWS and combinations thereof. To address the specifics and needs of a wide variety of EWS designs, a classification of EWS is provided, which focuses on the degree of automations encountered in varying EWS. The framework and its implementation are illustrated through a series of example applications of EWS in an alpine environment.

  12. Quantifying Airborne Induced Polarization effects in helicopter time domain electromagnetics

    Science.gov (United States)

    Macnae, James

    2016-12-01

    This paper derives the Airborne Induced Polarization (AIP) response of an airborne electromagnetic (AEM) system to a horizontal, thin sheet conductor. A vertical component double-dipole approximates helicopter systems with towed concentric horizontal transmitter and receiver loops in frequency- or time-domain. In time domain, the AIP effect typically shows up as late-time negative data with amplitude 4 to 5 orders of magnitude smaller than the early-time peak of the positive AEM responses. Because of limited bandwidth from the short sample time after the decay of inductive responses, accurate extraction of intrinsic AIP parameters other than a minimum chargeability is almost impossible. Modelling further suggests that AIP effects in double-dipole AEM systems can only be reliably detected from polarizable material in the top few tens of metres. A titanium mineral exploration case history from the Lac Brûlé area, Quebec, Canada illustrates strong spatial coherence of AIP minimum chargeability estimates and their independence from other effects such as conductivity and magnetic susceptibility.

  13. Tillage, crop residue, and nutrient management effects on soil organic carbon sequestration in rice-based cropping systems: a review

    Science.gov (United States)

    Sequestration of soil organic carbon (SOC) is one of the major agricultural strategies to mitigate greenhouse gas emissions, enhance food security, and improve agricultural sustainability. This paper synthesizes the much-needed state-of-knowledge on the effects of management practices, such as tilla...

  14. 免耕对北方旱作玉米土壤水分及物理性质的影响%Effects of no-tillage on soil water content and physical properties of spring corn fields in semiarid region of northern China

    Institute of Scientific and Technical Information of China (English)

    余海英; 彭文英; 马秀; 张科利

    2011-01-01

    Field experiments were conducted in 2006-2008 to study the effects of no-tillage on the spatiotemporal dynamics of soil water content and related soil physical properties in spring com fields in Beijing region during growth season. In study period, the water storage in 0-100 cm soil layer in tillage and no-tillage treatments had the same variation trend with time and precipitation,but the water storage at different time periods and under different precipitations was 2. 7%-30. 3% higher in no-tillage treatment than in tillage treatment. When the precipitation was relatively abundant, the increment of soil water storage was somewhat increased, but no-tillage was still worth to be popularized in the regions relatively deficit in precipitation. Under no-tillage, the average water storage in 0-100 cm soil layer during the three growth seasons in 2006-2008 was 3.4% -12. 8% higher than that under conventional tillage, and the increment of the water storage in 0-20 cm and 80-100 cm soil layers under no-tillage was higher than that in intermediate layer, with the highest increment reached 22.2%. No-tillage improved soil water-holding capacity and water use efficiency via decreasing soil bulk density, increasing soil porosity, and promoting the formation of soil waterstable aggregates, and thereby, promoted crop yielding. After 3 years no-tillage, the soil water use efficiency and spring corn yield were increased by 13.3% and 16.4%, respectively, compared with those under conventional tillage.%通过2006-2008年的田间试验,研究了北京地区免耕与传统翻耕条件下土壤水分的时空动态及其对土壤相关物理性质的影响.结果表明:研究期间,免耕和翻耕地0~100 cm土层的土壤贮水量随时间及降水变化的趋势一致,但免耕地的土壤贮水量在不同时刻以及不同降雨条件下均高于翻耕地,增幅在2.7%~30.3%,降雨相对充分条件下土壤贮水量的增量有所增加,但免耕在相对缺水

  15. Arsenic from community water fluoridation: quantifying the effect.

    Science.gov (United States)

    Peterson, Emily; Shapiro, Howard; Li, Ye; Minnery, John G; Copes, Ray

    2016-04-01

    Community water fluoridation is a WHO recommended strategy to prevent dental carries. One debated concern is that hydrofluorosilicic acid, used to fluoridate water, contains arsenic and poses a health risk. This study was undertaken to determine if fluoridation contributes to arsenic in drinking water, to estimate the amount of additional arsenic associated with fluoridation, and compare this to the National Sanitation Foundation/American National Standards Institute (NSF/ANSI) standard and estimates from other researchers. Using surveillance data from Ontario drinking water systems, mixed effects linear regression was performed to examine the effect of fluoridation status on the difference in arsenic concentration between raw water and treated water samples. On average, drinking water treatment was found to reduce arsenic levels in water in both fluoridated and non-fluoridated systems by 0.2 μg/L. However, fluoridated systems were associated with an additional 0.078 μg/L (95% CI 0.021, 0.136) of arsenic in water when compared to non-fluoridated systems (P = 0.008) while controlling for raw water arsenic concentrations, types of treatment processes, and source water type. Our estimate is consistent with concentrations expected from other research and is less than 10% of the NSF/ANSI standard of 1 μg/L arsenic in water. This study provides further information to inform decision-making regarding community water fluoridation.

  16. Quantifying ligand effects in high-oxidation-state metal catalysis

    Science.gov (United States)

    Billow, Brennan S.; McDaniel, Tanner J.; Odom, Aaron L.

    2017-09-01

    Catalysis by high-valent metals such as titanium(IV) impacts our lives daily through reactions like olefin polymerization. In any catalysis, optimization involves a careful choice of not just the metal but also the ancillary ligands. Because these choices dramatically impact the electronic structure of the system and, in turn, catalyst performance, new tools for catalyst development are needed. Understanding ancillary ligand effects is arguably one of the most critical aspects of catalyst optimization and, while parameters for phosphines have been used for decades with low-valent systems, a comparable system does not exist for high-valent metals. A new electronic parameter for ligand donation, derived from experiments on a high-valent chromium species, is now available. Here, we show that the new parameters enable quantitative determination of ancillary ligand effects on catalysis rate and, in some cases, even provide mechanistic information. Analysing reactions in this way can be used to design better catalyst architectures and paves the way for the use of such parameters in a host of high-valent processes.

  17. Quantifying the effect of investors' attention on stock market.

    Science.gov (United States)

    Yang, Zhen-Hua; Liu, Jian-Guo; Yu, Chang-Rui; Han, Jing-Ti

    2017-01-01

    The investors' attention has been extensively used to predict the stock market. Different from existing proxies of the investors' attention, such as the Google trends, Baidu index (BI), we argue the collective attention from the stock trading platforms could reflect the investors' attention more closely. By calculated the increments of the attention volume for each stock (IAVS) from the stock trading platforms, we investigate the effect of investors' attention measured by the IAVS on the movement of the stock market. The experimental results for Chinese Securities Index 100 (CSI100) show that the BI is significantly correlated with the returns of CSI100 at 1% significance level only in 2014. However, it should be emphasized that the correlation of the new proposed measure, namely IAVS, is significantly at 1% significance level in 2014 and 2015. It shows that the effect of the measure IAVS on the movement of the stock market is more stable and significant than BI. This study yields important invest implications and better understanding of collective investors' attention.

  18. Quantifying the effect of investors’ attention on stock market

    Science.gov (United States)

    Yang, Zhen-Hua; Liu, Jian-Guo; Yu, Chang-Rui; Han, Jing-Ti

    2017-01-01

    The investors’ attention has been extensively used to predict the stock market. Different from existing proxies of the investors’ attention, such as the Google trends, Baidu index (BI), we argue the collective attention from the stock trading platforms could reflect the investors’ attention more closely. By calculated the increments of the attention volume for each stock (IAVS) from the stock trading platforms, we investigate the effect of investors’ attention measured by the IAVS on the movement of the stock market. The experimental results for Chinese Securities Index 100 (CSI100) show that the BI is significantly correlated with the returns of CSI100 at 1% significance level only in 2014. However, it should be emphasized that the correlation of the new proposed measure, namely IAVS, is significantly at 1% significance level in 2014 and 2015. It shows that the effect of the measure IAVS on the movement of the stock market is more stable and significant than BI. This study yields important invest implications and better understanding of collective investors’ attention. PMID:28542216

  19. Warmer and Wetter Soil Stimulates Assimilation More than Respiration in Rainfed Agricultural Ecosystem on the China Loess Plateau: The Role of Partial Plastic Film Mulching Tillage.

    Science.gov (United States)

    Gong, Daozhi; Hao, Weiping; Mei, Xurong; Gao, Xiang; Liu, Qi; Caylor, Kelly

    2015-01-01

    Effects of agricultural practices on ecosystem carbon storage have acquired widespread concern due to its alleviation of rising atmospheric CO2 concentrations. Recently, combining of furrow-ridge with plastic film mulching in spring maize ecosystem was widely applied to boost crop water productivity in the semiarid regions of China. However, there is still limited information about the potentials for increased ecosystem carbon storage of this tillage method. The objective of this study was to quantify and contrast net carbon dioxide exchange, biomass accumulation and carbon budgets of maize (Zea maize L.) fields under the traditional non-mulching with flat tillage (CK) and partial plastic film mulching with furrow-ridge tillage (MFR) on the China Loess Plateau. Half-hourly net ecosystem CO2 exchange (NEE) of both treatments were synchronously measured with two eddy covariance systems during the growing seasons of 2011 through 2013. At same time green leaf area index (GLAI) and biomass were also measured biweekly. Compared with CK, the warmer and wetter (+1.3°C and +4.3%) top soil at MFR accelerated the rates of biomass accumulation, promoted greater green leaf area and thus shortened the growing seasons by an average value of 10.4 days for three years. MFR stimulated assimilation more than respiration during whole growing season, resulting in a higher carbon sequestration in terms of NEE of -79 gC/m2 than CK. However, after considering carbon in harvested grain (or aboveground biomass), there is a slight higher carbon sink (or a stronger carbon source) in MFR due to its greater difference of aboveground biomass than that of grain between both treatments. These results demonstrate that partial plastic film mulched furrow-ridge tillage with aboveground biomass exclusive of grain returned to the soil is an effective way to enhance simultaneously carbon sequestration and grain yield of maize in the semiarid regions.

  20. Warmer and Wetter Soil Stimulates Assimilation More than Respiration in Rainfed Agricultural Ecosystem on the China Loess Plateau: The Role of Partial Plastic Film Mulching Tillage.

    Directory of Open Access Journals (Sweden)

    Daozhi Gong

    Full Text Available Effects of agricultural practices on ecosystem carbon storage have acquired widespread concern due to its alleviation of rising atmospheric CO2 concentrations. Recently, combining of furrow-ridge with plastic film mulching in spring maize ecosystem was widely applied to boost crop water productivity in the semiarid regions of China. However, there is still limited information about the potentials for increased ecosystem carbon storage of this tillage method. The objective of this study was to quantify and contrast net carbon dioxide exchange, biomass accumulation and carbon budgets of maize (Zea maize L. fields under the traditional non-mulching with flat tillage (CK and partial plastic film mulching with furrow-ridge tillage (MFR on the China Loess Plateau. Half-hourly net ecosystem CO2 exchange (NEE of both treatments were synchronously measured with two eddy covariance systems during the growing seasons of 2011 through 2013. At same time green leaf area index (GLAI and biomass were also measured biweekly. Compared with CK, the warmer and wetter (+1.3°C and +4.3% top soil at MFR accelerated the rates of biomass accumulation, promoted greater green leaf area and thus shortened the growing seasons by an average value of 10.4 days for three years. MFR stimulated assimilation more than respiration during whole growing season, resulting in a higher carbon sequestration in terms of NEE of -79 gC/m2 than CK. However, after considering carbon in harvested grain (or aboveground biomass, there is a slight higher carbon sink (or a stronger carbon source in MFR due to its greater difference of aboveground biomass than that of grain between both treatments. These results demonstrate that partial plastic film mulched furrow-ridge tillage with aboveground biomass exclusive of grain returned to the soil is an effective way to enhance simultaneously carbon sequestration and grain yield of maize in the semiarid regions.

  1. Quantifying Chiral Magnetic Effect from Anomalous-Viscous Fluid Dynamics

    CERN Document Server

    Jiang, Yin; Yin, Yi; Liao, Jinfeng

    2016-01-01

    Chiral Magnetic Effect (CME) is the macroscopic manifestation of the fundamental chiral anomaly in a many-body system of chiral fermions, and emerges as anomalous transport current in the fluid dynamics framework. Experimental observation of CME is of great interest and has been reported in Dirac and Weyl semimetals. Significant efforts have also been made to search for CME in heavy ion collisions. Encouraging evidence of CME-induced charge separation in those collisions has been reported, albeit with ambiguity due to background contamination. Crucial for addressing such issue, is the need of quantitative predictions for CME signal with sophisticated modelings. In this paper we develop such a tool, the Anomalous Viscous Fluid Dynamics (AVFD) framework, which simulates the evolution of fermion currents in QGP on top of the data-validated VISHNU bulk hydrodynamic flow. With realistic initial conditions and magnetic field lifetime, the AVFD-predicted CME signal could be quantitatively consistent with measured ch...

  2. Quantifying the "chamber effect" in CO2 flux measurements

    Science.gov (United States)

    Vihermaa, Leena; Childs, Amy; Long, Hazel; Waldron, Susan

    2014-05-01

    The significance of aquatic CO2 emissions has received attention in recent years. For example annual aquatic emissions in the Amazon basin have been estimated as 500 Mt of carbon1. Methods for determining the flux rates include eddy covariance flux tower measurements, flux estimates calculated from partial pressure of CO2 (pCO2) in water and the use floating flux chambers connected to an infra-red gas analyser. The flux chamber method is often used because it is portable, cheaper and allows smaller scale measurements. It is also a direct method and hence avoids problems related to the estimation of the gas transfer coefficient that is required when fluxes are calculated from pCO2. However, the use of a floating chamber may influence the flux measurements obtained. The chamber shields the water underneath from effects of wind which could lead to lower flux estimates. Wind increases the flux rate by i) causing waves which increase the surface area for efflux, and ii) removing CO2 build up above the water surface, hence maintaining a higher concentration gradient. Many floating chambers have an underwater extension of the chamber below the float to ensure better seal to water surface and to prevent any ingress of atmospheric air when waves rock the chamber. This extension may cause additional turbulence in flowing water and hence lead to overestimation of flux rates. Some groups have also used a small fan in the chamber headspace to ensure thorough mixing of air in the chamber. This may create turbulence inside the chamber which could increase the flux rate. Here we present results on the effects of different chamber designs on the detected flux rates. 1Richey et al. 2002. Outgassing from Amazonian rivers and wetlands as a large tropical source of atmospheric CO2. Nature 416: 617-620.

  3. 3D Structure of Tillage Soils

    Science.gov (United States)

    González-Torre, Iván; Losada, Juan Carlos; Falconer, Ruth; Hapca, Simona; Tarquis, Ana M.

    2015-04-01

    Soil structure may be defined as the spatial arrangement of soil particles, aggregates and pores. The geometry of each one of these elements, as well as their spatial arrangement, has a great influence on the transport of fluids and solutes through the soil. Fractal/Multifractal methods have been increasingly applied to quantify soil structure thanks to the advances in computer technology (Tarquis et al., 2003). There is no doubt that computed tomography (CT) has provided an alternative for observing intact soil structure. These CT techniques reduce the physical impact to sampling, providing three-dimensional (3D) information and allowing rapid scanning to study sample dynamics in near real-time (Houston et al., 2013a). However, several authors have dedicated attention to the appropriate pore-solid CT threshold (Elliot and Heck, 2007; Houston et al., 2013b) and the better method to estimate the multifractal parameters (Grau et al., 2006; Tarquis et al., 2009). The aim of the present study is to evaluate the effect of the algorithm applied in the multifractal method (box counting and box gliding) and the cube size on the calculation of generalized fractal dimensions (Dq) in grey images without applying any threshold. To this end, soil samples were extracted from different areas plowed with three tools (moldboard, chissel and plow). Soil samples for each of the tillage treatment were packed into polypropylene cylinders of 8 cm diameter and 10 cm high. These were imaged using an mSIMCT at 155keV and 25 mA. An aluminium filter (0.25 mm) was applied to reduce beam hardening and later several corrections where applied during reconstruction. References Elliot, T.R. and Heck, R.J. 2007. A comparison of 2D and 3D thresholding of CT imagery. Can. J. Soil Sci., 87(4), 405-412. Grau, J, Médez, V.; Tarquis, A.M., Saa, A. and Díaz, M.C.. 2006. Comparison of gliding box and box-counting methods in soil image analysis. Geoderma, 134, 349-359. González-Torres, Iván. Theory and

  4. Quantifying the Intercontinental and Global Reach and Effects of Pollution

    Science.gov (United States)

    Chatfield, Robert B.; Guo, Zitan

    2000-01-01

    The Atmospheric Chemistry Modeling Group is participating in an international effort to explore the projected interactions of the atmosphere with biota, human activity, and the natural environment over the next three decades. The group uses computer simulations and statistical analyses to compare theory and observations of the composition of the lower atmosphere. This study of global habitability change is part of a more ambitious activity to understand global habitability. This broad planetary understanding is central to planetary habitability, biomarker detection, and similar aspects of Astrobiology. The group has made highly detailed studies of immense intercontinental plumes that affect the chemistry of the global atmosphere, especially the region below the ozone (O3) layer whose chemical composition defines the conditions for healthy humans and the biosphere. For some decades there has been concern about the pollution from cities and industrial burning and its possible effect in increasing smog ozone, not only in continental regions, but also in plumes that spread downwind. Recently, there has been new concern about another kind of pollution plume. Projections for a greatly expanded aircraft fleet imply that there will be plumes of nitrogen oxides (NO(x)) from jet exhaust in the Northern Hemisphere downwind of major air traffic routes. Both of these are tied to large-scale O3 in the troposphere, where it is toxic to humans and plant tissues.

  5. The Effect of Seeding Rates and Nitrogen fertilizer on Yield and Yield Components of Wheat Cultivars in Corn residue (No Tillage

    Directory of Open Access Journals (Sweden)

    D Omidi Nasab

    2016-02-01

    Full Text Available Introduction Lots of studies have been conducted for increasing the wheat yield per unit area through sustainable agriculture, which is included low tillage and no tillage farming systems. Furthermore, nitrogen is the important element which is used to increase crop yield. On the other hand, if all the required conditions especially cultivar and fertilizer are at optimum level, but density is not appropriate, the maximum yield per unit area will not be achieved. Therefore, this study was conducted to evaluate the effect of seeding rates and nitrogen fertilizer on yield and yield components of wheat cultivars in corn residue. Materials and Methods An split factorial experiment in a randomized complete block design with four replications and three factors including cultivar at 2 levels, (Chamran (V1 and Behrang (V2, seed density at 5 levels (50 (D1, 100 (D2, 150 (D3, 200 (D4, 250 (D5 kg ha-1 and nitrogen fertilizers from urea source at 6 levels (0 (N1, 50 (N2, 100 (N3, 150 (N4, 200 (N5, 250 (N6 carried out in fall of 2011 – 2012 at Agricultural Farm located south of Dezful. Results and Discussion The results indicated that with increasing plant density, the number of spike and biological yield increased, however the number of grain in each spike and thousand seed weight decreased. Moreover, increasing nitrogen application resulted in increasing the number of spike, the number of grain in each cluster, thousand seed weight, biological yield and grain yield. seed consumption over than 100 (kg ha-1 decreased grain yield . In addition, applied nitrogen to 150 (kg ha-1 significantly increased grain yield. The effects of plant density on grain yield illustrated that the highest grain yield was obtained using 100 kg seeds per hectare. Furthermore, there were not any significant differences among 150, 200 and 250 kg seeds per hectare and they were at a lower level of grain yield. In addition, Chamran cultivar, with 413.70 (kg ha-1 average grain yield

  6. Tillage Effects on Soil Active Organic Carbon in Purple Paddy Soil%耕作方式对紫色水稻土活性有机碳的影响

    Institute of Scientific and Technical Information of China (English)

    吴艳; 郝庆菊; 江长胜

    2011-01-01

    The effects of tillage system on total soil organic carbon, soil active organic carbon and soil stable organic carbon were studied in a long-term field experimental station in Chongqing, China. The content of total soil organic carbon in the 0 - 60 cm soil layers under different tillage systems was LM: no-till and ridge culture with rotation of rice and rape system (22.74 g/kg)> DP: conventional tillage with rice only system (14.57 g/kg)> XM: no-till and plain culture with rotation of rice and rape system (13.73 g/kg)> LF: tillage and ridge culture with rotation of rice and rape system (13.10 g/kg)>SH: conventional tillage with rotation of rice and rape system ( 11.92 g/kg). The order of soil active organic carbon was LM(22.74 g/kg) > DP( 14.57 g/kg) > XM( 13.73 g/kg) > LF( 13.10 g/kg)> SH( 11.92 g/kg). The proportion of soil stable organic carbon to total soil organic carbon was LM(85% )> SH(78% )> XM(77% ) > LF(75% ) > DP(74% ). Overall, long-term LM treatment performed good effects on the soil carbon sequestration and fixation.%以位于西南大学试验农场的紫色土长期免耕试验田为研究对象,探讨不同耕作方式一冬水田平作(DP)、水旱轮作(SH)、垄作免耕(LM)、厢作免耕(XM)和垄作翻耕(LF)对紫色水稻土总有机碳、活性有机碳及稳态碳的影响.结果表明,在0~60 cm的土壤深度内,不同耕作方式下总有机碳的平均含量为LM(22.74 g/kg)>DP(14.57 g/kg)>XM(13.73 g/kg)>LF(13.10g/kg)>SH(11.92 g/kg);活性有机碳的平均含量为DP(3.67 g/kg)>LF(3.49 g/kg)>LM(3.28 g/kg)>XM(3.17 g/kg)>SH(2.69 g/kg);稳态碳占土壤总有机碳的百分比为LM(85%)>SH(78%)>XM(77%)>LF(75%)>DP(74%).长期垄作免耕具有明显的碳截存效应和良好的固碳能力.

  7. Effects of Conservation Tillage and Cropping Patterns on Vegetables Topsoil CO2 Content%保护性耕作及种植模式对蔬菜地耕层土壤CO2含量的影响

    Institute of Scientific and Technical Information of China (English)

    鲁耀; 段宗颜; 胡万里; 陈宝红; 陈拾华; 杨文柱

    2011-01-01

    采用动态气室法分别对云南省通海县山地蔬菜地、长期连作蔬菜地及不同种植模式下的露地蔬菜地20cm耕层土壤CO2含量进行田间直接测定,分析了不同保护性耕作措施及种植模式对土壤CO2含量的影响,同时分析了保护性耕作措施对蔬菜产量的影响.结果表明,以秸秆还田及有机物质增施为代表的保护性耕作措施能显著提高土壤CO2含量;秸秆覆盖和免耕相结合既有利于土壤呼吸产生CO2,又有利于蔬菜产量、产值提高,但免耕、深耕土壤CO2产生量无显著差异;增施有机物质总体上有利于蔬菜产量、产值提高,增施不同有机物质对蔬菜生产的影响顺序为烟杆>家禽、家畜粪便>废弃蔬菜叶>稻草,其中稻草对蔬菜具有较大的负面影响;土壤CO2含量与耕地利用情况密切相关,土壤CO2含量大小表现为水田>旱坡地;蔬菜-蔬菜连作>水稻/烤烟/玉米-蔬菜轮作;蔬菜-蔬菜连作地5年>10年>20年.%To analyze the effect of conservation tillage and cropping patterns on vegetables topsoil CO2 content and conservation tillage on vegetables outputs, the 20 cm topsoil CO3 content of mountain vegetables, the long-term continuous cropping of vegetables and different cropping patterns in fields were respectively and directly measured by dynamic chamber method in Tonghai county Yunnan province. The results showed that the straw and other increasing organic matter, represented by measures of conservation tillage could evidently improve the soil CO2 content. No-tillage with straw cover was conducive to soil respiration to produce CO2 and vegetables output, but there was no significant difference between the no-tillage and deep plow. The vegetable outputs increased generally by tobacco straw > poultry and livestock manure > waste organic matter > rice straw, and rice straw had a greater negative effect on vegetables production. Soil CO2 content was nearly related to

  8. Carbon dioxide emissions under different soil tillage systems in mechanically harvested sugarcane

    Science.gov (United States)

    Silva-Olaya, A. M.; Cerri, C. E. P.; La Scala, N., Jr.; Dias, C. T. S.; Cerri, C. C.

    2013-03-01

    Soil tillage and other methods of soil management may influence CO2 emissions because they accelerate the mineralization of organic carbon in the soil. This study aimed to quantify the CO2 emissions under conventional tillage (CT), minimum tillage (MT) and reduced tillage (RT) during the renovation of sugarcane fields in southern Brazil. The experiment was performed on an Oxisol in the sugarcane-planting area with mechanical harvesting. An undisturbed or no-till (NT) plot was left as a control treatment. The CO2 emissions results indicated a significant interaction (p residues to the adoption of green cane harvesting. The CO2 emissions in the CT system could respond to a loss of 80% of the potential soil C accumulated over one year as result of the adoption of mechanized sugarcane harvesting. Meanwhile, soil tillage during the renewal of the sugar plantation using RT and MT methods would result in low impact, with losses of 12% and 2% of the C that could potentially be accumulated during a one year period.

  9. Effects of different tillage measures on formation of grain and forage maize yield%不同耕作措施对粮饲兼用玉米产量形成的影响

    Institute of Scientific and Technical Information of China (English)

    张立健; 李玲玲; 谢军红; 李婧

    2015-01-01

    Field experiments of different tillage (conventional tillage,no tillage,rotary tillage,subsoi-ling)were studied for all film double furrow sowing and water use of forming technology of grain and for-age maize yield from 2012 to 2013 in Longzhong Semiarid Hilly and gully region of Loess Plateau.The re-sults show that subsoiling tillage and rotary tillage of leaf area index under conventional tillage and no till-age was similar,increased 27.12%~40.24%,photosynthetic potential and dynamic changes of leaf area in-dex were basically the same.The amount of dry matter accumulation were rotary tillage,subsoiling and no tillage,conventional tillage > in each growth period,rotary tillage and deep tillage tillage double spike rate,ear diameter,1 000 grain weight were higher than conventional tillage and no tillage.Two years aver-age biological yield,economic yield and straw yield rotary tillage and deep tillage treatment were higher, and higher water use efficiency.Therefore,deep tillage and rotary tillage by increasing the leaf area index increased leaf photosynthetic potential,thus increased the dry matter accumulation in maize,and enhanced double spike rate,source organ photosynthates to grain transfer,promoted the ear growth,ultimately bene-ficial to grain and forage maize grain yield and biological yield and water use to improve the efficiency of the water.Deep tillage and rotary tillage is suitable for areas of the film double furrow sowing technology un-der ideal grain and forage maize cultivation of soil and water loss in the Loess Plateau .%2012~2013年在陇中黄土高原半干旱丘陵沟壑区采用大田试验研究了不同耕作措施(传统耕作、免耕、旋耕、深松耕)对全膜双垄沟播技术下粮饲兼用玉米产量形成及水分利用的影响.结果表明:深松耕与旋耕下叶面积指数相近,较传统耕作与免耕提高27.12%~40.24%,光合势动态变化与叶面积指数基本一致;各生育时期干物质积累量都表现

  10. 麦稻轮作区周年耕作模式对作物产量和土壤特性的影响%Effect of Different Annual Tillage Patterns on Crop Yield and Soil Properties in Wheat-rice Rotation System

    Institute of Scientific and Technical Information of China (English)

    李朝苏; 汤永禄; 黄钢; 吴春; 马孝玲

    2012-01-01

    2004~2009年,在成都平原麦稻轮作区研究了不同周年耕作模武(周年翻耕无秸秆还田、小麦免耕稻草覆盖还田+水稻旋耕无秸秆还田、麦稻周年免耕秸秆全量还田、麦稻周年垄作免耕秸秆全量还田)对作物产量和土壤特性的影响.结果表明,不同模式闻小麦产量差异较小,水稻产量差异较大;免旋结合稻草覆盖还田模式年际间水稻产量较其他模式稳定.麦稻关健生育阶段0~30cm土层速效养分含量模式间差异较小;免旋结合稻草覆盖利于土壤表层有机质积累.周年免耕秸秆全量还田模武20cm处紧实度降低,渗水速率增大,保水性能下降.研究结果说明,不同耕作模式下土壤养分供给能力不是影响作物产量的主要因素,因土壤物理性质变化导致水分下渗差异是水稻产量差异的重要原因,免旋结合稻草覆盖还田模式似乎更利于麦稻轮作田生产能力的稳定.%The wheat-rice rotation system was the major cropping system in south Asia and the Yangtze River Basin of China. From 2004 to 2009, the effect of different annual tillage patterns on crop yields and soil properties in a wheat-rice rotation system was studied in the Chengdu Plain. The effects of four tillage patterns (annual plowing, no-tillage in wheat season with rice straw returning and rotary tillage in rice season, annual no-tillage with rice and wheat straw returning, annual ridge-no-tillage with rice and wheat straw retuming)were tested in the experiment. The results showed that the difference in wheat yield among different treatments in the same year was not significant, but the difference in rice yield was obvious. The rice yield of the treatments with annual no-tillage and total straw mulching was lower than that of the control treatment with annual plowing and no straw returning, and decreased over the years. The rice yield of the treatments with no tillage in the wheat season and rice straw returning and

  11. 耕作方式对紫色水稻土颗粒态氮的影响%Effect of Tillage Systems on Soil Particulate Organic Nitrogen in a Purple Paddy Soil

    Institute of Scientific and Technical Information of China (English)

    刘志祥; 郝庆菊; 江长胜; 祝滔

    2011-01-01

    土壤颗粒态氮作为土壤有机氮中的非稳定性部分,对土壤中氮的平衡有着重要的影响,对作物的生长及增产增收也有着重要意义.试验以西南大学农业部重庆紫色土生态环境重点野外科学观测试验站内于1989年设立的长期免耕试验田为研究对象,研究冬水田平作、水旱轮作、垄作免耕和垄作翻耕等耕作方式对土壤颗粒态氮的影响.结果表明,不同耕作方式下土壤全氮及颗粒态氮含量均具有明显的垂直分布特征,由上到下含量逐渐降低.在0-60 cm的土壤深度内,土壤全氮平均含量依次为垄作免耕(1.53g/kg)>冬水田平作(1.50 g/kg)>垄作翻耕(1.31 g/kg)>水旱轮作(1.16 g/kg);颗粒态氮平均含量依次为冬水田平作(0.55 g/kg)>垄作免耕(0.46 g/kg)>垄作翻耕(0.40 g/kg)>水旱轮作(0.35 g/kg).免耕能够增加土壤全氮含量,但无助于颗粒态氮含量的增加.不同耕作方式下的颗粒态土碳氮比大于全土碳氮比,表明颗粒态土壤有机质易被微生物分解,是土壤营养物质的重要来源.%Soil particulate organic nitrogen as the instable part of soil organic nitrogen, playing an important role in the nitrogen balance, and is of great significance in the growth of plant and the increase of crop yield. In this paper four tillage treatments including conventional tillage with rice only system (DP), conventional tillage with rotation of rice and rape system (SH), no-till and ridge culture with rotation of rice and rape system (LM), and tillage and ridge culture with rotation of rice and rape system (LF) were selected as research objectives to study the effect of tillage system on soil particulate organic nitrogen. The tillage experiment was established in the Key Field Station for Monitoring of Eco-Environment of Purple Soil of the Ministry of Agriculture of China located in the farm of southwest university (30°26 N, 106°26 E) , Chongqing. The results indicated that soil total nitrogen

  12. The Effect of Different in-situ Water Conservation Tillage Methods on Growth and Development of Taro (Colocasia esculenta L.

    Directory of Open Access Journals (Sweden)

    A.M. Manyatsi

    2011-01-01

    Full Text Available Taro (Colocasia esculenta L. is an important food crop in the diet of Swazi people. However, there is dearth of information in the country on appropriate agronomic practices which can adequately conserve soil moisture to meet taro crop water requirements. The effects of in-situ water conservation practices on growth, development and yield of taro were investigated. Five in-situ water conservation methods/treatments [tied ridges, ridges, half moon, flat (not irrigated and flat (irrigated] were evaluated. The flat (irrigated treatment served as a control. The experiment was conducted in a sandy clay loam soil at Luyengo. The treatments were laid in a randomized complete block design (RCBD replicated three times. Each plot measured 5.0 m x 5.0 m with inter-row spacing of 0.9 m and intra- row plant spacing of 0.3 m for flat seedbeds. The ridges were 0.3 m high and 1 m apart, and ties were 0.2 m high spaced at 0.5 m intervals. The half moons had a diameter of 0.5 m. Planting was done in October 2009 using corms. The plants were rainfed, except for the irrigated treatment where irrigation w as done to field capacity when soil moisture matric potential reached 10 bars. Parameters measured included soil moisture, plant emergence, plant height, number of leaves, leaf length and leaf width. Leaf area and Leaf Area Index (LAI were calculated. The fresh yield of corms was measured at 24 weeks after planting. The results showed plant emergence rate after three weeks being highest under the half moon, at 94% followed in decreasing order by irrigated flat at 90% , tied ridges at 85%, ridges at 82% and lastly flat (not irrigated at 80%. The various treatments did not show significant (p>0.05 differences in plant height throughout the growing period. However plants grown in irrigated flat plots consistently exhibited significantly (p<0.01 the highest number of leaves compared to other treatments. A similar trend w as also observed with LAI. Taro corm yield were

  13. Effects of Biological Tillage on Soil Microbiota and Bacterial Physiologies Colony%生物耕作对菜田土壤微生物区系及细菌生理类群的影响

    Institute of Scientific and Technical Information of China (English)

    李双喜; 郑宪清; 袁大伟; 张娟琴; 何七勇; 吕卫光

    2012-01-01

    Field plot experiments were carried out to investigate the effect of biological tillage on soil microbiota and microbial physiologies colony. Three treatments which were conventional tillage (CK) ,no tillage (Tl) and biological tillage ( T2) were set up. The results showed that biological tillage could increase the nutrient contents and the soil moisture content compared with CK,especially in the 5 -20 cm layer,in which the contents of soil organic matter,total nitrogen,available phosphorous,and soil moisture content were improved 58.33% ,68.93% ,67.06% and 16. 19% Respectively. The numbers of microbial physiologies colony obviously increased in Tl and T2. The application of maize to soil ( T2 ) gave significantly higher number of bacteria, actinomycete and lower number of fungi (P <0.05) ,so did the numbers of ammonifier.nitrifier, inorganic phosphorus decomposing microbes(P <0.05). Increasing earthworm activity was contributive to improve soil physicochemical properties and enzyme activities in agro-ecosystem, which was very important in improving soil fertilization.%旨在研究生物耕作(接种蚯蚓)对土壤微生物区系及细菌生理类群的影响.结果表明,生物耕作能有效提高不同耕层的土壤养分含量和含水量,其中尤以5~20 cm显著,生物耕作处理土壤有机质、全氮、有效磷以及含水量依次比对照增长了58.33%,68.93%,67.06%,16.19%;与常规旋耕(CK)相比,各土层中免耕(T1)和生物耕作(T2)2种保护性耕作方式可明显增加土壤微生物生理类群的数量,且表层(0~5 cm)土壤微生物数量远远大于下层(5~20 cm).T2处理显著增加了土壤中的细菌和放线菌数量,降低了真菌数量(P<0.05);氮化细菌、硝化细菌以及无机磷分解菌等生理细菌数量得到显著提升(P<0.05).在传统的农业生态系统中,培育土壤有益动物生物数量可以提高土壤微生物和酶活性,对改善农田土壤肥力有着重要意义.

  14. Influence of Conservation Tillage on Soil Aggregates Features in North China Plain

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Tillage greatly influences the aggregation and stability of soil aggregates. This study investigated the effects of conservation tillage on soil aggregate characteristics. During a four-year study period (2001-2005), soils were sampled from no-tillage (NT), rotary tillage (RT), and conventional tillage (moldboard tillage, CT) plots at the Luancheng Agriculture and Ecology Experimental Station in Hebei Province, China, and the amount, size distribution, and fractal dimension of the aggregates were examined by dry and wet sieving methods. The results indicated that NT significantly increased the topsoil (0-5 cm) bulk density (BD), while RT maintained a lower BD as CT. Dry sieving results showed that NT had higher macro-aggregate content (R0.25), and a larger mean weight diameter (MWD) and geometric mean diameter (GMD) than other treatments in the 0-10 cm layer, while RT showed no difference from CT. In wet sieving, results showed that most of the aggregates were unstable, and the MWD and GMD of water-table aggregates showed the trend of NT > RT > CT. At 0-5 cm layer, the fractal dimension (D) of water-stable aggregates under NT was lower than it was under RT and CT. At 5-10 em, RT yielded the highest D, and showed stability. After four years, NT increased the aggregation and the stability of soil aggregates; while due to intense disturbance, the aggregation and stability of the upper layer (0-10 cm) under RT and CT decreased.

  15. Impact of tillage erosion on water erosion in a hilly landscape.

    Science.gov (United States)

    Wang, Y; Zhang, J H; Zhang, Z H; Jia, L Z

    2016-05-01

    Little has been known of the interaction between tillage erosion and water erosion, while the two erosion processes was independently studied. Can tillage-induced soil redistribution lead to exaggerated (or retarded) runoff flow and sediment concentrations in steeply sloping fields? A series of simulated tillage and artificial rainfall events were applied to rectangular runoff plots (2m×8m) with a slope of 15° to examine the impacts of tillage erosion intensities on water erosion in the Yangtze Three Gorges Reservoir Area, China. Mean flow velocity, effective/critical shear stress, and soil erodibility factor K were calculated to analyze the differences in hydrodynamic characteristics induced by tillage. Our experimental results suggest that mean runoff rates were 2.26, 1.19, and 0.65Lmin(-1) and that mean soil detachment rates were 1.53, 1.01, and 0.61gm(-2)min(-1) during the 70-min simulated rainfall events for 52-, 31-, and 10-year tillage, respectively. A significant difference (Perosion increases soil erodibility and delivers the soil for water erosion in sloping fields, accelerating water erosion.

  16. Conversion of Conservation Tillage to Rotational Tillage to Reduce Phosphorus Losses during Snowmelt Runoff in the Canadian Prairies.

    Science.gov (United States)

    Liu, Kui; Elliott, Jane A; Lobb, David A; Flaten, Don N; Yarotski, Jim

    2014-09-01

    In a preceding study, converting conventional tillage (ConvT) to conservation tillage (ConsT) was reported to decrease nitrogen (N) but to increase phosphorus (P) losses during snowmelt runoff. A field-scale study was conducted from 2004 to 2012 to determine if conversion of ConsT to rotational tillage (RotaT), where conservation tillage was interrupted by a fall tillage pass every other year, could effectively reduce P losses compared with ConsT. The RotaT study was conducted on long-term paired watersheds established in 1993. The ConvT field in the pair has remained under ConvT practice since 1993, whereas tillage was minimized on the ConsT field from 1997 until 2007. In fall 2007, RotaT was introduced to the ConsT field, and heavy-duty cultivator passes were conducted in the late fall of years 2007, 2009, and 2011. Runoff volume and nutrient content were monitored at the edge of the two fields, and soil and crop residue samples were taken in each field. Greater soil Olsen P and more P released from crop residue are likely the reasons for the increased P losses in the ConsT treatment (2004-2007) relative to the ConvT treatment (2004-2007). Analysis of covariance indicated that, compared with ConsT (2004-2007), RotaT (2008-2012) increased the concentrations of dissolved organic carbon (DOC) by 62%, total dissolved N (TDN) by 190%, and total N (TN) by 272% and increased the loads of DOC by 34%, TDN by 34%, and TN by 60%. However, RotaT (2008-2012) decreased soil test P in surface soil, P released from crop residue, and duration of runoff compared with ConsT (2004-2007) and thus decreased the concentrations of total dissolved P (TDP) by 46% and total P (TP) by 38% and decreased the loads of TDP by 56% and TP by 42%. In the Canadian Prairies, where P is a major environmental concern compared with N, RotaT was demonstrated to be an effective practice to reduce P losses compared with ConsT.

  17. From Dust Bowl to Conservation Tillage.

    Science.gov (United States)

    McDonald, Dale

    1992-01-01

    Examines the causes of the dust bowl and recent changes in tillage practices in Oklahoma and other prairie states that conserve soil. Briefly discusses the success of programs that target school children for conservation education. (LZ)

  18. Eficácia do herbicida acetochlor na semeadura direta e convencional com ou sem palha e os efeitos sobre o rendimento do milho Acetochlor herbicide efficacy on tillage and no-tillage systems on straw mulch presence or absence and effect on corn yield

    Directory of Open Access Journals (Sweden)

    Miguel Vicente Weiss Ferri

    2004-04-01

    Full Text Available O experimento foi conduzido na Faculdade de Agronomia da Universidade Federal do Rio Grande do Sul, ano agrícola de 2000/2001, com o objetivo de avaliar a eficácia de controle das plantas daninhas com o herbicida acetochlor em Argissolo Vermelho, conduzido sob semeadura direta e preparo convencional, na presença ou ausência de palha. O delineamento experimental utilizado foi blocos casualizados com quatro repetições. Os tratamentos constaram de acetochlor nas doses de 0, 1680, 3360 e 5040g ha-1, aplicado em solo sob semeadura direta e preparo convencional, na presença (4,5t ha-1 ou ausência de palha de aveia. Foram avaliados o controle das plantas daninhas, além da altura de plantas e rendimento de grãos de milho. O acetochlor foi mais eficiente para o controle das plantas daninhas no preparo convencional, comparado à semeadura direta. A palha reduziu a eficácia de controle pelo acetochlor. A altura das plantas de milho foi maior na semeadura direta. O rendimento de grãos de milho foi maior no preparo convencional e na presença da palha devido ao melhor controle das plantas daninhas.An experiment was carried out at Federal University at Rio Grande do Sul, with the objective of avaluating herbicide acetochlor efficacy on conventional tillage and no-till soils. The soil is classified as at Paleudult. The following treatments were tested: acetochlor at 0, 1680, 3360 and 5040g ha-1, applied on tillage and no-tillage systems on oat straw mulch presence (4,5t ha-1 and absence. Assessements included crop injury, weed control at 15, 30 and 45 days after herbicide application, and corn crop yeld. The weed control with acetochlor herbicide was more efficient on tillage than on no-tillage system. Straw mulch reduced acetochlor herbicide weed control. Corn plant height was higher on no-tillage than on tillage systems, indicating lower herbicide activity on the first. Corn yield was higher on tillage system and straw mulch presence, due to

  19. Effects of different mechanical tillage methods on soil physical and chemical properties and rice yield with straw returning%不同机械耕作方式对稻田秸秆还田土壤理化性状及产量的影响

    Institute of Scientific and Technical Information of China (English)

    何七勇; 吕卫光; 郑宪清; 李双喜; 张娟琴; 王金庆; 袁大伟; 张翰林

    2015-01-01

    通过秸秆还田大田试验,考察不同机械耕作方式对稻田土壤理化性质、水稻苗期生长状况及产量的影响。结果显示,不同机械耕作方式对稻田土壤物理性质影响不大,但旋耕铧犁处理可以显著增加土壤速效氮和速效磷含量;不同耕作方式对水稻初苗期生长有一定影响,但苗期结束时各处理间无显著差异;在稻田秸秆还田条件下,采用旋耕铧犁耕作方式可显著提高水稻产量。%Based on field experiments of straw returning,the effects of different mechanical tillage methods on soil physical and chemical properties,rice seedlings growth status and yields were investigated.The results showed that there was little effect of mechanical tillage methods on paddy soil physical properties,but the treat-ment of rotary tillage plough could significantly increase available nitrogen and available phosphorus of soil.Me-chanical tillage methods had a certain effect on the rice seedlings growth status in early seedling stage,but there was no significant difference among the treatments at the end of seedling stage.The rotary tillage plough treatment could significantly improve the rice yield with straw returning.

  20. 正反转旋耕作业的秸秆混埋效果比较%Comparison of straw incorporation effect with down-cut and up-cut rotary tillage

    Institute of Scientific and Technical Information of China (English)

    陈青春; 石勇; 丁启朔; 丁为民; 田永超

    2015-01-01

    Due to the complexity of soil and straw properties and the interactions among soil, straw and tillage tools, specific straw incorporating implements were designed and developed for particular working conditions. Different types of rotary tillers that adapted to different field states were produced in the last decades for straw burial. However, past efforts of assessment on rotary tillers were focused mainly on their soil working performances. Seldom has been done to assess the performance of rotary tillers and their effect on both soil disturbance and straw distribution in the tilled soil layer. A field experiment was thus conducted to compare the performances of rotary tillers on mediating soil and straw after rice harvesting. A mini-power rotor tiller was run on a platform developed for in-situ tillage test. Soil surface and micro-relief was measured with profilometer. Straw distribution was measured with a three-dimension coordinate tester. The measured results were transferred to Pro-E software, in which the measured data of straw distribution in soil were modeled and assessed. It was found that down-cut rotary tillage resulted into a gently humped soil surface over the tilled region, whereas the up-cut treatment led to a sink of soil surface in the mid region and the ridges along two sides of the tilled plot. Severe humping of fragmented soil was also observed in the up-cut tillage. It was therefore concluded that, for min-power rotor tillers in paddy field, the down-cut tillage provided better surface micro-relief than the up-cut. A higher percentage of buried straw, 88.91%, was acquired with the down-cut tilling. But it was low for the up-cut, which was 83.26%. The heaping-up of straw was also severe in the up-cut treatment, which was 33.02%, 8.19% higher than that from the down-cut. This indicated that the down-cut was more preferable for mini-power rotor tiller design compared with the up-cut. Analysis on the sectioned regions with the Pro-E revealed more

  1. 分层旋耕对水稻土耕层物理性状的影响%Effect of stratified rotary tillage on paddy soil physical properties

    Institute of Scientific and Technical Information of China (English)

    张军; 丁启朔; 丁为民; 李毅念; 邱威; 陆明洲; 薛金林; 田永超

    2015-01-01

    [目的]稻麦轮作制因稻季土壤淹水沉实及长期浅耕等因素导致耕层浅薄、土壤硬化,成为阻碍旱季作物生长的主导因素,拟论证使用分层旋耕(stratified rotary tillage,SRT)实现水稻土深松的技术可行性.[方法]构建原位分层旋耕试验台,通过对比分析免耕(no tillage,NT)、常规旋耕(conventional rotary tillage,CRT)与分层旋耕3种耕作方式的稻茬麦各生理期的土壤持水量、密度、含水率、土壤硬度等的连续变化情况,论证分层旋耕对水旱轮作制旱作季土壤物理性状的影响.[结果]分层旋耕可显著改善土壤物理性状.SRT与NT和CRT相比,可有效增加土壤疏松层深度、提高土壤持水量、降低土壤密度与贯入阻力.SRT处理后10~20 cm土层的平均持水量分别比NT、CRT高3.6%和3.5%,平均密度分别比NT、CRT低0.14和0.13 t·m-3,麦季各时期土壤含水率明显提高,分别比CRT、NT高0.34%和1.21%.SRT明显降低0~30 cm的平均贯入阻力,其从大到小顺序依次为SRT、CRT和NT;SRT比CRT增加耕层厚度10 cm.[结论]分层旋耕耕作是解决水旱轮作区土壤硬化的适宜耕作技术,分层旋耕有利于改善稻茬田的土壤物理性状,从而利于促进旱季作物的生长.

  2. EFFECTS OF MULCHING AND TILLAGE ON SOIL FERTILITY OF UPLAND RICE FIELD%不同耕作方式下覆草旱作稻田土壤肥力特征

    Institute of Scientific and Technical Information of China (English)

    王栋; 李辉信; 胡锋

    2011-01-01

    A field experiment was carried out during the period from 2005 to 2007 to investigate the effects of straw mulching and tillage on soil physical, chemical and biological properties of upland rice field that has been under the double-rice cropping system since 2003 in the seasonal arid region of South China (Yujiang County, Jiangxi Province). Results show that there was no significant difference between the treatments, I. E. conventional flooded rice cultivation (CF) , upland rice cultivation with straw mulching (SM) , and non-tillage upland rice cultivation with straw mulching (N-SM) in soil bulk density and total porosity in 0 - 15 cm depth soil layer. But Treatment N-SM significantly increased soil organic matter, total N, alkalystic N and soil basal respiration, and both Treatments SM and N-SM significantly increased soil microbial biomass carbon content and the activities of urease and saccharase, as was compared with Treatment CF. Therefore, the findings suggest that upland rice cultivation with straw mulching and non-tillage upland rice cultivation with straw mulching may be cited as novel water-saving and fertility building rice cultivation models for extrapolation in this region.%通过始建于2003年中国南方季节性干旱区(江西省余江县)的双季稻田定位试验,于2005~2007年研究了水稻覆草旱作和免耕覆草旱作对稻田土壤理化性质和生物学性质的影响.结果表明,覆草旱作、免耕覆草旱作的耕层土壤容重和总孔隙度与常规水作的差异不显著.与常规水作相比,免耕覆草旱作显著提高土壤有机质、全氮、碱解氮和土壤基础呼吸;与常规水作相比,覆草旱作和免耕覆草旱作均显著提高土壤微生物生物量碳含量、脲酶和蔗糖酶活性.由此可知,覆草旱作和免耕覆草旱作可以作为该区积极推行的具有培肥地力作用的节水型稻作栽培模式.

  3. Effect of Short-term No-tillage on Soil Water Physical Property of Soybean Field in Black Soil Zone%黑土区短期免耕对大豆田土壤水分物理性质的影响

    Institute of Scientific and Technical Information of China (English)

    江恒; 韩晓增; 邹文秀; 杨春葆

    2012-01-01

    耕作和施肥是影响土壤水分物理性质的2个重要因素,为探讨免耕和长期单施化肥对土壤水分物理性质的影响及它们之间的交互作用,以海伦农田生态系统国家野外科学观测研究站内的长期定位试验为基础,研究了施用化肥+传统耕作(NP+CT),施用化肥+免耕(NP+NT),无肥+传统耕作(CK+ CT),无肥+免耕(CK+NT)对土壤水分物理性质的影响.短期免耕(3 a)后显著地增加黑土水稳性团聚体的稳定性,表现在与传统耕作相比水稳定性大团聚体(>0.25 mm)的含量、平均重量直径和平均几何直径分别提高9.03%,10.90%和20.39%.耕作和施肥对土壤水稳性团聚体稳定性的影响没有显著的交互作用,但是与施肥相比,耕作方式能够解释更多的土壤水稳性团聚体稳定性的变异.免耕显著增加了0~10 cm土层土壤的容重,减少了土壤总孔隙度、饱和含水量、毛管含水量和田间持水量,施肥仅对0 ~10cm土层土壤毛管含水量产生了显著的影响.耕作和施肥对0~ 10 cm土层土壤的容重具有显著的交互作用,同时与施肥相比,耕作能够解释更多的0~ 10 cm土层土壤的容重、总孔隙度、饱和含水量、毛管含水量和田间持水量的变异.耕作和施肥对10 ~ 20 cm土层土壤的水分物理性质影响不显著.因此,在研究区域内耕作是影响土壤水分物理性质的一个重要措施.%Tillage and fertilization are two important factors impacting soil water physical properties. For finding out the effect of tillage and fertilization on soil water physical properties and their interactions, we researched the influence of four treatments , including chemical fertilizer plus traditional tillage (NP + CT) , chemical fertilizer plus no-tillage ( NP + NT) , no-fertilizer plus traditional tillage(CK + CT)and no-fertilizer plus no-tillage(CK + NT) ,on soil water physical properties based on long-term field experiments located in Hailun

  4. Effects of Tillage Mode on Characteristics of Photosynthesis and Root Growth of Rice%耕作方式对水稻光合及根系生理特性的影响

    Institute of Scientific and Technical Information of China (English)

    全妙华; 胡爱生; 欧立军; 胡冬炎; 李必湖

    2012-01-01

    A comparative study was conducted between the cultivation of ridge tillage (RT) and the cultivation of conventional tillage (CT) on the photosynthetic characteristics, root growth and major agronomic characters with 9311, a rice variety, as the material. The results showed that, compared with CT, RT had a statistically significant increase in photosynthetic characteristics including photosynthetic rate, stomatal conductance and water use efficiency. With regard to root growth characters, RT had much more roots per plant, higher root dry weight per plant, stronger root vigor and higher activity of CAT, SOD, POD of roots but lower MDA content of roots. Besides, the number of tillers and effective panicles per plant of RT was greatly increased by 16. 67% and 33.98% , respectively. It is concluded that RT can increase rice yield by improving root absorption, increasing tillers and effective panicles and raising photosynthesis of rice.%以9311为材料,对水稻垄作和传统耕作方式下的光合特性、根系特点和主要农艺性状进行了比较研究.结果表明,与传统耕作方式相比,垄作方式下水稻的光合速率(PN)、气孔导度(g.)和水分利用率(WUE)等光合参数的值均显著增大,根条数、根干重、根系活力和根系CAT、SOD、POD酶活性极显著提高,MDA含量极显著下降,分蘖数和有效穗数分别增加16.67%和33.98%.垄作主要通过改善根系吸收,增加分蘖和有效穗数及提高光合速率,达到增产的目的.

  5. Saturated hydraulic conductivity and porosity within macroaggregates modified by tillage

    Energy Technology Data Exchange (ETDEWEB)

    Park, E.J.; Smucker, A.J.M. (MSU)

    2010-07-20

    Greater knowledge of intraaggregate porosity modifications by tillage conveys new information for identifying additional hydrologic, ion retention, and aggregate stability responses to specific management practices. Macroaggregates, 2 to 4, 4 to 6.3, and 6.3 to 9.5 mm across, were separated into multiple concentric layers and their porosities were determined. Saturated hydraulic conductivity (K{sub s}) of multiple aggregate fractions from two soil types subjected to conventional tillage (CT), no tillage (NT), and native forest (NF) soils were measured individually to identify the effects of tillage on aggregate structure, porosity, and K{sub s}. Intraaggregate porosities were the highest in NF aggregates. Greater porosities were identified in exterior layers of soil aggregates from all treatments. Lowest intraaggregate porosities were observed in the central regions of CT aggregates. Soil aggregates, 6.3 to 9.5 mm across, had the greatest total porosities, averaging 37.5% for both soil types. Long-term CT reduced intraaggregate porosities and K, within macroaggregates, of the same size fraction, from both the Hoytville silty clay loam and Wooster silt loam soil types. Values for K, of NF aggregates, 5.0 x 10{sup -5} cm s{sup -1}, were reduced 50-fold by long-term CT treatments of the Hoytville series. The K, values through Wooster aggregates from NF, 16.0 x 10{sup -5} cm s{sup -1}, were reduced 80-fold by long-term CT treatments. The K{sub s} values through NF and NT aggregates were positively correlated with their intraaggregate porosities (R{sup 2} = 0.84 for NF and R{sup 2} = 0.45 for NT at P < 0.005). Additional studies are needed to identify rates at which pore geometries within macroaggregates are degraded by CT or improved by NT.

  6. Influence of Different Straight Tillage & Contour Tillage Measures on Nitrogen Loss from Runoff and Runoff Loss%“大横坡+小顺坡”耕作模式对氮及径流流失的影响

    Institute of Scientific and Technical Information of China (English)

    张怡; 何丙辉; 唐春霞

    2013-01-01

    The effect of different straight tillage & contour tillage measures in plot on nitrogen loss from runoff and runoff loss have been studied in Soil and Water Conservation Station in Zhongxian County, Chongqing. These results indicate that, compared with runoff under total straight tillage measure, runoff of 6 m straight tillage & 2 m contour tillage, 5 m straight tillage & 3 m contour tillage, 4 m straight tillage & 4 m contour tillage reduce 41. 74%, 45. 84% and 59. 63% respectively. There are no significant differences between four kinds of tillage measures on the total nitrogen loss during the duration of rainfall of 6. 62 h-16. 32 h. when less than 5. 12 h, there are significant differences between 4 m straight tillage &-4 m contour tillage and other tillage, and the best effect for 4 m straight tillage & 4 m contour tillage. In the condition of duration of rainfall of 2. 51 h and 3. 22 h, there are significant differences between each other; The soluble nitrogen loss accounts for most of the nitrogen loss from runoff, and the proportion of soluble nitrogen loss accounts for total nitrogen loss is influenced by rainfall intensity and duration of rainfall. The loss of total nitrogen and soluble nitrogen per area of different straight tillage & contour tillage measures are significant lower than that of total straight tillage measure.%以重庆市忠县水土保持试验站为研究平台,对小区尺度下“大横坡+小顺坡”耕作模式对氮及径流流失的影响进行研究,结果表明:与全顺坡模式比较,6 m顺坡+2m横坡模式,5 m顺坡+3m横坡模式和4 m顺坡+4m横坡模式径流量分别减少了41.74%,45.84%和59.63%;在总氮流失上,在降雨历时为6.62~16.32 h,3种“大横坡+小顺坡”耕作模式之间无显著差异,当降雨历时小于5.12h时,4m顺坡+4m横坡模式与其他3种模式差异性显著,以4 m顺坡+4m横坡模式保持总氮效果最好,其中当降雨历时为2.51h和3.22h时,4种耕作模式之间

  7. Influence of conservation tillage and zero tillage on arable weeds in organic faba bean production

    Directory of Open Access Journals (Sweden)

    Jung, Rüdiger

    2016-02-01

    Full Text Available The field experiments were conducted in 2008, 2009 and 2010 on a Gleyic Cambisol near Goettingen, Lower Saxony, Germany. A crop sequence of summer barley, winter cover crops (intercropped oat and sunflower and summer faba bean was examined under organic farming conditions. Emphasis was given to the studying of arable weeds in faba beans. However, enhancing symbiotic nitrogen fixation of summer faba beans by accumulation of soil-nitrogen by winter cover crops was a second objective in these experiments. The faba bean field plots had been cultivated with three different tillage systems: 1. zero tillage, sowing with cross-slottechnique, 2. conservation tillage (wing share cultivator, rotary harrow sowing with cross-slot-technique and 3. conventional tillage with mouldboard plough followed by rotary harrow, sowing with precision monoseeder. In plots with zero tillage preceding cover crops were left as mulch on the soil surface. Cover crops accumulated adequate nitrogen amounts and following faba beans reacted with significant increase (up to 10% in symbiotic nitrogen fixation. Maximum of arable weed biomass was observed in zero tillage-plots at the end of May or early in June. The abundance of the predominant weed wild mustard (Sinapis arvensis increased with tillage intensity, whereas the abundance of creeping thistle (Cirsium arvense increased in 2010 with decreasing tillage intensity. Average grain yield of faba beans was low with only 3.0 and 2.4 t ha-1 in 2009 and 2010, respectively.

  8. Influence of tillage practices on soil biologically active organic matter content over a growing season under semiarid Mediterranean climate

    Directory of Open Access Journals (Sweden)

    D. Martín-Lammerding

    2013-02-01

    Full Text Available In semiarid areas, traditional, intensive tillage has led to the depletion of soil organic matter, which has resulted in reduced soil fertility. The aim of the present work was to evaluate the effects of different soil management systems, practised over 12 years, on soil organic carbon (SOC, nitrogen (SN and biologically active organic matter (particulate organic matter [POM]; potentially mineralisable nitrogen [PMN]; microbial biomass [MB]. A Mediterranean Alfisol, located in central Spain, was managed using combinations of conventional tillage (CT, minimum tillage (MT or no-tillage (NT, plus a cropping background of either continuous wheat (WW or a fallow/wheat/pea/barley rotation (FW. Soil was sampled at two depths on four occasions during 2006-2007. The results showed the sampling date and the cropping background to significantly affect the SOC (p<0.0057 and p<0.0001 respectively. Tillage practice, however, had no effect on SOC or SN. The C-and N-POM contents were significantly influenced by the date, tillage and rotation. These variables were significantly higher under NT than CT and under WW than FW. The PMN was influenced by date, tillage and rotation, while C-MB was significantly affected by tillage (p< 0.0063, but not by rotation. The NT plots accumulated 66% C-POM, 60% N-POM, 39% PMN and 84% C-MB more than the CT plots. After more than 12 years, the benefits of conservation practices were found in the considered soil properties, mainly under no tillage. In order to obtain a consistent data set to predict soil biological status, it is necessary further study over time.

  9. Inoculum Potential of Fusarium spp. Relates to Tillage and Straw Management in Norwegian Fields of Spring Oats.

    Science.gov (United States)

    Hofgaard, Ingerd S; Seehusen, Till; Aamot, Heidi U; Riley, Hugh; Razzaghian, Jafar; Le, Vinh H; Hjelkrem, Anne-Grete R; Dill-Macky, Ruth; Brodal, Guro

    2016-01-01

    The increased occurrence of Fusarium-mycotoxins in Norwegian cereals over the last decade, is thought to be caused by increased inoculum resulting from more cereal residues at the soil surface as a result of reduced tillage practices. In addition, weather conditions have increasingly promoted inoculum development and infection by Fusarium species. The objective of this work was to elucidate the influence of different tillage regimes (autumn plowing; autumn harrowing; spring plowing; spring harrowing) on the inoculum potential (IP) and dispersal of Fusarium spp. in spring oats. Tillage trials were conducted at two different locations in southeast Norway from 2010 to 2012. Oat residues from the previous year's crop were collected within a week after sowing for evaluation. IP was calculated as the percentage of residues infested with Fusarium spp. multiplied by the proportion of the soil surface covered with residues. Fusarium avenaceum and F. graminearum were the most common Fusarium species recovered from oat residues. The IP of Fusarium spp. was significantly lower in plowed plots compared to those that were harrowed. Plowing in either the autumn or spring resulted in a low IP. Harrowing in autumn was more effective in reducing IP than the spring harrowing, and IP levels for the spring harrowed treatments were generally higher than all other tillage treatments examined. Surprisingly low levels of F. langsethiae were detected in the residues, although this species is a common pathogen of oat in Norway. The percentage of the residues infested with F. avenaceum, F. graminearum, F. culmorum, and F. langsethiae generally related to the quantity of DNA of the respective Fusarium species determined using quantitative PCR (qPCR). Fusarium dispersal, quantified by qPCR analysis of spore trap samples collected at and after heading, generally corresponded to the IP. Fusarium dispersal was also observed to increase after rainy periods. Our findings are in line with the general

  10. Inoculum potential of Fusarium spp. relates to tillage and straw management in Norwegian fields of spring oats

    Directory of Open Access Journals (Sweden)

    Ingerd Skow Hofgaard

    2016-04-01

    Full Text Available The increased occurrence of Fusarium-mycotoxins in Norwegian cereals over the last decade, is thought to be caused by increased inoculum resulting from more cereal residues at the soil surface as a result of reduced tillage practices. In addition, weather conditions have increasingly promoted inoculum development and infection by Fusarium species. The objective of this work was to elucidate the influence of different tillage regimes (autumn plowing; autumn harrowing; spring plowing; spring harrowing on the inoculum potential (IP and dispersal of Fusarium spp. in spring oats. Tillage trials were conducted at two different locations in southeast Norway from 2010 to 2012. Oat residues from the previous year’s crop were collected within a week after sowing for evaluation. IP was calculated as the percentage of residues infested with Fusarium spp. multiplied by the proportion of the soil surface covered with residues. F. avenaceum and F. graminearum were the most common Fusarium species recovered from oat residues. The IP of Fusarium spp. was significantly lower in plowed plots compared to those that were harrowed. Plowing in either the autumn or spring resulted in a low IP. Harrowing in autumn was more effective in reducing IP than the spring harrowing, and IP levels for the spring harrowed treatments were generally higher than all other tillage treatments examined. Surprisingly low levels of F. langsethiae were detected in the residues, although this species is a common pathogen of oat in Norway. The percentage of the residues infested with F. avenaceum, F. graminearum, F. culmorum and F. langsethiae generally related to the quantity of DNA of the respective Fusarium species determined using qPCR. Fusarium dispersal, quantified by quantitative PCR analysis of spore trap samples collected at and after heading, generally corresponded to IP. Fusarium dispersal was also observed to increase after rainy periods. Our findings are in line with the

  11. Inoculum Potential of Fusarium spp. Relates to Tillage and Straw Management in Norwegian Fields of Spring Oats

    Science.gov (United States)

    Hofgaard, Ingerd S.; Seehusen, Till; Aamot, Heidi U.; Riley, Hugh; Razzaghian, Jafar; Le, Vinh H.; Hjelkrem, Anne-Grete R.; Dill-Macky, Ruth; Brodal, Guro

    2016-01-01

    The increased occurrence of Fusarium-mycotoxins in Norwegian cereals over the last decade, is thought to be caused by increased inoculum resulting from more cereal residues at the soil surface as a result of reduced tillage practices. In addition, weather conditions have increasingly promoted inoculum development and infection by Fusarium species. The objective of this work was to elucidate the influence of different tillage regimes (autumn plowing; autumn harrowing; spring plowing; spring harrowing) on the inoculum potential (IP) and dispersal of Fusarium spp. in spring oats. Tillage trials were conducted at two different locations in southeast Norway from 2010 to 2012. Oat residues from the previous year’s crop were collected within a week after sowing for evaluation. IP was calculated as the percentage of residues infested with Fusarium spp. multiplied by the proportion of the soil surface covered with residues. Fusarium avenaceum and F. graminearum were the most common Fusarium species recovered from oat residues. The IP of Fusarium spp. was significantly lower in plowed plots compared to those that were harrowed. Plowing in either the autumn or spring resulted in a low IP. Harrowing in autumn was more effective in reducing IP than the spring harrowing, and IP levels for the spring harrowed treatments were generally higher than all other tillage treatments examined. Surprisingly low levels of F. langsethiae were detected in the residues, although this species is a common pathogen of oat in Norway. The percentage of the residues infested with F. avenaceum, F. graminearum, F. culmorum, and F. langsethiae generally related to the quantity of DNA of the respective Fusarium species determined using quantitative PCR (qPCR). Fusarium dispersal, quantified by qPCR analysis of spore trap samples collected at and after heading, generally corresponded to the IP. Fusarium dispersal was also observed to increase after rainy periods. Our findings are in line with the

  12. INFLUÊNCIA DO PREPARO DE SOLO E DA ROTAÇÃO DE CULTURAS NA SEVERIDADE DE PODRIDÕES RADICULARES NO FEIJOEIRO COMUM EFFECTS OF SOIL TILLAGE SYSTEM AND CROP ROTATION ON DRY BEAN ROOT ROT SEVERITY

    Directory of Open Access Journals (Sweden)

    Pedro Marques da Silveira

    2007-09-01

    Full Text Available

    As podridões radiculares do feijoeiro são causadas pelos fungos Rhizoctonia solani Kühn e Fusarium solani f. sp. phaseoli Snyd. & Hans. Neste trabalho testou-se a combinação dos fatores preparo de solo e rotação de culturas, além de se avaliarem seus efeitos sobre as podridões radiculares do feijoeiro. Os tipos de preparo de solo consistiram em: arado+grade (P1, arado (P2, grade (P3 e plantio direto (P4. As rotações de culturas foram: arroz-feijão (R1, milho-feijão (R2, arroz/calopogônio (Calopogonium muconoides-feijão (R3 e milho-feijão-milho-feijão-arroz-feijão (R4. A severidade de F. solani f. sp. phaseoli, avaliada aos 25 dias após o plantio, apresentou interação significativa, sendo a maior severidade encontrada na combinação da rotação R3 com o preparo de solo P1, e a menor severidade, na combinação da rotação R2 com o preparo de solo P3. Diferenças estatísticas ocorreram na severidade da doença provocada por R. solani. O preparo de solo P3 apresentou maior severidade que P4, e, entre as rotações, R3 apresentou a maior severidade da doença.

    PALAVRAS-CHAVE: Rhizoctonia solani; Fusarium solani f. sp. phaseoli; práticas culturais; fungos.

    Dry bean root rot is caused by the fungi Rhizoctonia solani Kühn and Fusarium solani f. sp. phaseoli Snyd. & Hans.The effects of the interaction between soil tillage systems andcrop rotation on the severity of root rot was tested. The soiltillage systems consisted of plough+harrow (P1, plough (P2,harrow (P3 and no tillage (P4 and the crop rotation treatmentswere rice-bean (R1, corn-bean (R2, rice/Calopogonium muconoides-bean (R3 and corn

  13. Effects of Different Tillage Methods on the Photosynthetic Traits of Maize Leaf%不同耕作方式对玉米叶片冠层光合特性的影响

    Institute of Scientific and Technical Information of China (English)

    刘武仁; 郑金玉; 罗洋; 郑洪兵; 李瑞平; 李伟堂; 李征; 胡庆生; 杨秀梅

    2012-01-01

    以郑单958为试验材料,在已经定位研究28年留茬深松(DT)、免耕(NT)、翻耕(PT)和传统耕法(CT)的基础上,探讨不同耕作方式对玉米叶片光合特性的影响.结果表明,不同耕作方式下玉米叶片的净光合速率(Pn)处理间存在差异,DT处理比NT、PT和CT分别高8.78%、25.50%和48.13%,NT处理比PT和CT分别高15.38%和16.00%,PT处理比CT高0.54%,DT和NT处理分别与CT差异达显著水平(p<0.05),其他处理间差异不显著(2010年);气孔导度(Gs)、胞间二氧化碳浓度(Ci)、蒸腾速率(Tr)和水分利用效率(WUE)处理间存在差异,差异不显著.%Zhengdan958 was chosen as experiment material, the impacts of long-term (28 years) deep tillage with high stubble, no-tillage, plow tillage and conventional tillage on maize photosynthesis were assessed. The test results showed that there were different leaf photosynthesis rates of maize among different tillage, leaf photosynthesis rates on deep tillage(DT) 8.78%, 25.50% and 48.13% higher than on on-tillage(NT), plow tillage(PT) and conventional tillage (CT). Similarly, leaf photosynthesis rates on NT were 15.38% higher than on PT and CT. Besides, leaf photosynthesis rates on plow tillage were 0.54% higher than on conventional tillage. However, Gs, Ci, Tr and WUE of maize leaf were different among tillage, but, there were not significant.

  14. Comparing Nitrous Oxide Emissions from Paired No-Tillage and Conventional Tillage Agricultural Fields in the Northwest US: Insights from a Year of Intensive Monitoring

    Science.gov (United States)

    Waldo, S.; Kostyanovsky, K.; Pressley, S. N.; Huggins, D. R.; Stockle, C.; O'Keeffe, P.; Lamb, B. K.

    2015-12-01

    Agricultural soils are the main anthropogenic source of nitrous oxide (N2O), a potent greenhouse gas (GHG) and ozone depleting substance. Due to a high degree of both spatial and temporal variability coupled with limited availability of high-precision N2O sensors, emissions of N2O are difficult to quantify at the regional and field levels, scales important for determining best management practices. This study combined the use of automated static chambers and the flux gradient micrometeorological technique to continuously monitor emissions of N2O over two canola fields with differing tillage management: no-tillage and conventional tillage. Each site was instrumented with an array of sixteen chambers for the entire 2015 crop year (1 Oct - 30 Sept), and the N2O emissions were measured with the flux gradient method from 1 April thru 30 September. The chamber measurements indicated cumulative annual emissions of 6.0 and 3.1 kg N2O-N ha-1 for the conventional tillage and no-tillage sites, respectively, or 4.8% and 2.5% of applied fertilizer N. Emissions at the conventional tillage site were very low until the field was planted and fertilized, when emissions increased dramatically and stayed high until crop senesce. The growing season (1 April - June 15) accounted for 80% of total measured N2O losses (4.8 kg N2O-N ha-1). In contrast, the no-till site was characterized by consistent moderate emissions, and no spike after planting and fertilization was observed. The growing season only accounted for 30% of the total emissions (1.0 kg N2O-N ha-1). However, even sixteen chambers may not properly capture hot spots of emissions, and the spatially integrated flux gradient results did not corroborate the chamber results. The total emissions measured by the flux gradient method over the growing season were 1.6 and 1.4 kg N2O-N ha-1 for the conventional tillage and no-till sites, respectively. Further work on integrating the two techniques will be necessary to optimize

  15. Predicting Suitable field workdays for soil tillage in North Central ...

    African Journals Online (AJOL)

    Oladimeji S. Ife

    A simulation model was developed to predict suitable field workdays for tillage operations in North Central ... KEYWORDS: Suitable field workdays, tillage, agro –meteorology, tractability. 1. ... approach, the calculation of the components.

  16. Determination of crop residues and the physical and mechanical properties of soil in different tillage systems

    Directory of Open Access Journals (Sweden)

    P Ahmadi Moghaddam

    2016-04-01

    Full Text Available Introduction: Monitoring and management of soil quality is crucial for sustaining soil function in ecosystem. Tillage is one of the management operations that drastically affect soil physical quality. Conservation tillage methods are one of the efficient solutions in agriculture to reduce the soil erosion, air pollution, energy consumption, and the costs, if there is a proper management on the crop residues. One of the serious problems in agriculture is soil erosion which is rapidly increased in the recent decades as the intensity of tillage increases. This phenomenon occurs more in sloping lands or in the fields which are lacking from crop residues and organic materials. The conservation tillage has an important role in minimizing soil erosion and developing the quality of soil. Hence, it has attracted the attention of more researchers and farmers in the recent years. Materials and Methods: In this study, the effect of different tillage methods has been investigated on the crop residues, mechanical resistance of soil, and the stability of aggregates. This research was performed on the agricultural fields of Urmia University, located in Nazloo zone in 2012. Wheat and barley were planted in these fields, consecutively. The soil texture of these fields was loamy clay and the factorial experiments were done in a completely randomized block design. In this study, effect of three tillage systems including tillage with moldboard (conventional tillage, tillage with disk plow (reduced tillage, chisel plow (minimum tillage and control treatment on some soil physical properties was investigated. Depth is second factor that was investigated in three levels including 0-60, 60-140, and 140-200 mm. Moreover, the effect of different percentages of crop residues on the rolling resistance of non-driving wheels was studied in a soil bin. The contents of crop residues have been measured by using the linear transects and image processing methods. In the linear

  17. Quantifying effects of land use change on soil organic matter at the landscape scale

    NARCIS (Netherlands)

    Sonneveld, M.P.W.; Apeldoorn, van D.F.; Pepers, K.H.; Hanegraaf, M.C.

    2012-01-01

    Geophysical Research Abstracts Vol. 14, EGU2012-8153, 2012 EGU General Assembly 2012 © Author(s) 2012 Quantifying effects of land use change on soil organic matter at the landscape scale M.P.W. Sonneveld (1), D.F. Van Apeldoorn (1), K.H. Pepers (1), and M.C. Hanegraaf (2) (1) Land Dynamics Group, Wa

  18. Enhanced computational methods for quantifying the effect of geographic and environmental isolation on genetic differentiation

    NARCIS (Netherlands)

    Botta, Filippo; Eriksen, Casper; Fontaine, Michael Christophe; Guillot, Gilles

    2015-01-01

    In a recent paper, Bradburd et al. (2013) proposed a model to quantify the relative effect ofgeographic and environmental distance on genetic differentiation. Here, we enhance this method in several ways. 1. We modify the covariance model so as to fit better with mainstream geostatistical models and

  19. Quantifying the effects of pesticide exposure on annual reproductive success of birds

    Science.gov (United States)

    The Markov chain nest productivity model (MCnest) was developed for quantifying the effects of specific pesticide-use scenarios on the annual reproductive success of simulated populations of birds. Each nesting attempt is divided into a series of discrete phases (e.g., egg layin...

  20. Quantifying the effects of pesticide exposure on annual reproductive success of birds (presentation)

    Science.gov (United States)

    The Markov chain nest productivity model (MCnest) was developed for quantifying the effects of specific pesticide‐use scenarios on the annual reproductive success of simulated populations of birds. Each nesting attempt is divided into a series of discrete phases (e.g., egg ...

  1. Quantifying effects of land use change on soil organic matter at the landscape scale

    NARCIS (Netherlands)

    Sonneveld, M.P.W.; Apeldoorn, van D.F.; Pepers, K.H.; Hanegraaf, M.C.

    2012-01-01

    Geophysical Research Abstracts Vol. 14, EGU2012-8153, 2012 EGU General Assembly 2012 © Author(s) 2012 Quantifying effects of land use change on soil organic matter at the landscape scale M.P.W. Sonneveld (1), D.F. Van Apeldoorn (1), K.H. Pepers (1), and M.C. Hanegraaf (2) (1) Land Dynamics Group,

  2. Quantifying the effects of nitrogen on fruit growth and yield of cucumber crop in greenhouses

    NARCIS (Netherlands)

    Dai, J.; Liu, S.; Zhang, W.; Xu, R.; Luo, W.; Yin, X.; Han, L.; Chen, S.

    2011-01-01

    Nitrogen supply can improve crop growth and yield. An over-use of nitrogen fertilizer in greenhouse crop productions, however, causes many environmental problems. The aim of this study was to quantify the effects of nitrogen on fruit growth and yield so as to facilitate the optimization of nitrogen

  3. 连续秸秆还田与耕作方式轮换对稻麦轮作田土壤理化性状变化及水稻产量构成的影响%Effects of Continuous Returning Straws to Field and Shifting Different Tillage Methods on Changes of Physical-Chemical Properties of Soil and Yield Components of Rice

    Institute of Scientific and Technical Information of China (English)

    朱利群; 张大伟; 卞新民

    2011-01-01

    In order to reduce th e environmental pollution which caused by straw burning and improve the use efficiency of returning straws to field, the effects of continuous returning straws to field and different tillage methods on changes of physical-chemical properties of soil and yield composing factors of rice in farmland experiments were investigated. The results showed that deep tillage for two continuous years plus returning straws to field (DS Ⅱ ) and no-tillage with deep tillage each one year plus returning straws to field (NDS) were the most effective way to decrease soil bulk density in all the treatments. No-tillage with shallow plowing each one year plus returning straws to field (NLS) was the most effective way to increase soil organic matter. No-tillage with plowing sums rotary tillage each one year and rotary tillage for continuous two years had the best effects on increasing total nitrogen in soil. Returning straws to field increased available phosphorus content more significantly, but different tillage methods had no effect Returning straws to field could reduce grain number per panicle, 1000 grain weight and yields of rice. Grain number per panicle had been reduced by 12.14%, and 1000 grain weight had been reduced by 5.68% and yields had been reduced by 7.68%.%为减少秸秆焚烧带来的环境污染,提高秸秆还田的利用效率,采用大田试验研究了连续秸秆还田与不同耕作方式对稻麦轮作田土壤理化性状变化及水稻产量构成的影响.结果表明:所有处理中,连续两年深耕+秸秆还田处理(DSⅡ)和一年免耕一年深耕+秸秆还田处理(NDS)对土壤容重的降低最有效;一年免耕一年浅翻耕+秸秆还田处理(NLS)最能有效增加土壤有机质含量;一年免耕一年翻耕和旋耕(NRS、NLS、NDS)以及连续两年旋耕处理(RSⅡ)增加土壤全土层全氮含量效果最明显;秸秆还田处理全土层速效磷含量增加较明显,但是不同耕作方式对全土层速

  4. Long-term impact of reduced tillage and residue management on soil carbon stabilization: Implications for conservation agriculture on contrasting soil

    NARCIS (Netherlands)

    Chivenge, P.P.; Murwira, H.K.; Giller, K.E.; Mapfumo, P.; Six, J.

    2007-01-01

    Residue retention and reduced tillage are both conservation agricultural management options that may enhance soil organic carbon (SOC) stabilization in tropical soils. Therefore, we evaluated the effects of long-term tillage and residue management on SOC dynamics in a Chromic Luvisol (red clay soil)

  5. Long-term N fertilization and conservation tillage practices conserve surface but not profile SOC stocks under semi-arid irrigated corn

    Science.gov (United States)

    No tillage (NT) and N fertilization can increase surface soil organic C (SOC) stocks, but the effects deeper in the soil profile are uncertain. Subsequent tillage could counter SOC stabilized through NT practices by disrupting soil aggregation and promoting decomposition. We followed a long-term ti...

  6. 土地整治中底泥质耕作层土壤的构建方法及应用效果%Construction method and application effect on tillage layer soil by sediment in land consolidation engineering

    Institute of Scientific and Technical Information of China (English)

    刘永兵; 赵从举; 郭逸飞; 李翔; 刘永杰; 程言君; 张建中; 臧振远; 许杰峰; 杨文杰; 沈来新

    2015-01-01

    optimal stabilizing agents. Considering water content and stabilization period, the effective, low-cost and operable stabilizer dosage, remediation process, and parameters were proposed to finalize the sediment heavy metal stabilization approach. Moreover, sediment modification on soil remediation process needed to consider the regional topography and landscape, irrigation system, transportation, farmland protection, and other engineering conditions. By combining sediment pavement, land peeling, sediment heavy metal stabilization remediation into the project design, the feasible measure on building the sediment phase tillage layer soil was formulated. Last, through the experiment on spinach planted, the results showed that the heavy metal content in the spinach can achieve the nuisance-free level, reducing Cd content by 38.61%-85.69%, so it can obviously reduce heavy metal in vegetables. Sediment phase tillage layer soil is suitable for cultivation, raising productivity by 8.7%-13%, improving soil organic content by 0.95-2.18 times.

  7. Soil respiration, labile carbon pools, and enzyme activities as affected by tillage practices in a tropical rice-maize-cowpea cropping system.

    Science.gov (United States)

    Neogi, S; Bhattacharyya, P; Roy, K S; Panda, B B; Nayak, A K; Rao, K S; Manna, M C

    2014-07-01

    In order to identify the viable option of tillage practices in rice-maize-cowpea cropping system that could cut down soil carbon dioxide (CO2) emission, sustain grain yield, and maintain better soil quality in tropical low land rice ecology soil respiration in terms of CO2 emission, labile carbon (C) pools, water-stable aggregate C fractions, and enzymatic activities were investigated in a sandy clay loam soil. Soil respiration is the major pathway of gaseous C efflux from terrestrial systems and acts as an important index of ecosystem functioning. The CO2-C emissions were quantified in between plants and rows throughout the year in rice-maize-cowpea cropping sequence both under conventional tillage (CT) and minimum tillage (MT) practices along with soil moisture and temperature. The CO2-C emissions, as a whole, were 24 % higher in between plants than in rows, and were in the range of 23.4-78.1, 37.1-128.1, and 28.6-101.2 mg m(-2) h(-1) under CT and 10.7-60.3, 17.3-99.1, and 17.2-79.1 mg m(-2) h(-1) under MT in rice, maize, and cowpea, respectively. The CO2-C emission was found highest under maize (44 %) followed by rice (33 %) and cowpea (23 %) irrespective of CT and MT practices. In CT system, the CO2-C emission increased significantly by 37.1 % with respect to MT on cumulative annual basis including fallow. The CO2-C emission per unit yield was at par in rice and cowpea signifying the beneficial effect of MT in maintaining soil quality and reduction of CO2 emission. The microbial biomass C (MBC), readily mineralizable C (RMC), water-soluble C (WSC), and permanganate-oxidizable C (PMOC) were 19.4, 20.4, 39.5, and 15.1 % higher under MT than CT. The C contents in soil aggregate fraction were significantly higher in MT than CT. Soil enzymatic activities like, dehydrogenase, fluorescein diacetate, and β-glucosidase were significantly higher by 13.8, 15.4, and 27.4 % under MT compared to CT. The soil labile C pools, enzymatic activities, and

  8. 不同轮耕模式对黄土高原旱作麦田土壤物理性状的影响%Effects of Different Rotational Tillage Patterns on Soil Physical Properties in Rainfed Wheat Fields of the Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    程科; 李军; 毛红玲

    2013-01-01

    [目的]研究免耕、深松和翻耕两两组合而成的3种不同轮耕模式对黄土高原旱作麦田土壤物理结构与稳定性影响。[方法]于2007-2012年在陕西渭北旱塬麦田开展夏闲期免耕/深松、深松/翻耕和翻耕/免耕3种隔年交替的轮耕试验,测定土壤容重,并应用干筛和湿筛法分析土壤团聚体不同粒级含量、大小和分形维数。[结果]与耕作试验前相比,5年免耕/深松、深松/翻耕和翻耕/免耕处理在收获期0-60 cm 土层土壤容重与孔隙度差异均不显著。3种轮耕处理的耕层团聚体性状变化差异显著,0-10 cm土层大于0.25 mm水稳性团聚体含量(R0.25)及稳定率表现为免耕/深松>深松/翻耕>翻耕/免耕;0-30 cm 土层水稳性团聚体平均重量直径(mean weight diameter,MWD)大小表现为免耕/深松>深松/翻耕>翻耕/免耕。3种轮耕处理的团聚体分形维数(fractal dimension,D),干筛法下10-30 cm土层表现出差异,湿筛法下0-10 cm土层表现出差异,免耕/深松处理分形维数低于深松/翻耕和翻耕/免耕处理。[结论]3种轮耕模式对土壤容重的影响无显著差异。免耕/深松保护性轮耕模式能提高耕层团聚体含量与稳定性,改善旱地土壤结构;而深松/翻耕与翻耕/免耕的轮耕模式由于隔年翻耕对土壤的强烈扰动,对土壤结构改善效果不明显。%[Objective]Effects of three different rotational tillage patterns, which were pairwise combined with no-tillage(N), subsoiling(S) and conventional tillage(C), on soil physical structure and stability were studied in rainfed wheat fields of the Loess Plateau.[Method]The experiments of N/S (no-tillage in the first year, subsoiling in the second year, again no-tillage followed by alternating the next year), S/C (subsoiling in the first year, conventional tillage in the second year, again subsoiling followed by alternating the next year) and C/N (conventional

  9. Soil microbial community composition changes according to the tillage practice and plant development stage

    Science.gov (United States)

    Degrune, Florine; Dufrêne, Marc; Colinet, Gilles; Taminiau, Bernard; Hiel, Marie-Pierre; Daube, Georges; Vandenbol, Micheline

    2015-04-01

    Soil microorganisms are abundant and diverse and can have both beneficial and adverse effects on crop growth. Some, such as plant-growth-promoting rhizobacteria and mycorrhizae, are well known to favor crop productivity and plant health. They are notably involved in key processes such as improving plant nutrient acquisition, and they also play major roles in stimulating plant growth and protecting plants against pathogens by producing bioactive substances. Conversely, both agricultural practices and the plant development stage are known to influence the physical and chemical properties of the soil and hence the abundance and diversity of soil microorganisms. Here we investigated the impact of both tillage practice (conventional versus reduced tillage) and plant development stage (germination versus flowering) on the microbial community composition of an agricultural soil supporting a faba bean crop. Samples were taken at a depth of 15-20 cm from a silty soil in Belgium. For bacteria, we observed significant shifts in community composition according to both factors. Some changes were strongly related to the plant development stage and others to the tillage practice. Some taxa, including Gemmatimonas, Xanthomonadaceae, and Sinobacteraceae, showed a higher relative abundance at the flowering stage than at the germination stage, but no effect of tillage practice. Other taxa, including Flovobacterium, Chitinophaga, and Luteolibacter, showed a higher relative abundance under conventional tillage than under reduced tillage, but no change according to the stage of plant development. For fungi, significant shifts in community composition were observed according to the plant development stage. No effect of tillage practice was observed. The relative abundances of certain taxa, including Chaetomium and Clavicipitaceae, were higher during germination than during flowering, whereas other taxa, including Minimedusa and Teberdinia, showed a higher relative abundance during

  10. No tillage combined with crop rotation improves soil microbial community composition and metabolic activity.

    Science.gov (United States)

    Sun, Bingjie; Jia, Shuxia; Zhang, Shixiu; McLaughlin, Neil B; Liang, Aizhen; Chen, Xuewen; Liu, Siyi; Zhang, Xiaoping

    2016-04-01

    Soil microbial community can vary with different agricultural managements, which in turn can affect soil quality. The objective of this work was to evaluate the effects of long-term tillage practice (no tillage (NT) and conventional tillage (CT)) and crop rotation (maize-soybean (MS) rotation and monoculture maize (MM)) on soil microbial community composition and metabolic capacity in different soil layers. Long-term NT increased the soil organic carbon (SOC) and total nitrogen (TN) mainly at the 0-5 cm depth which was accompanied with a greater microbial abundance. The greater fungi-to-bacteria (F/B) ratio was found in NTMS at the 0-5 cm depth. Both tillage and crop rotation had a significant effect on the metabolic activity, with the greatest average well color development (AWCD) value in NTMS soil at all three soil depths. Redundancy analysis (RDA) showed that the shift in microbial community composition was accompanied with the changes in capacity of utilizing different carbon substrates. Therefore, no tillage combined with crop rotation could improve soil biological quality and make agricultural systems more sustainable.

  11. Effect of Different Tillage Methods on Photosynthetic Characteristics and Yield Formation in Summer Soybean%耕作方式对夏大豆光合特性及产量形成的影响

    Institute of Scientific and Technical Information of China (English)

    徐海东; 唐江华; 苏丽丽; 徐文修; 李亚杰

    2016-01-01

    为筛选出适合北疆地区种植复播大豆高产高效的耕作方式,研究了不同耕作方式对复播大豆光合特性、干物质积累及产量形成的影响。结果表明,翻耕覆膜处理的夏大豆叶面积指数和叶绿素相对含量值均最高,且均表现为翻耕覆膜处理>翻耕处理>旋耕处理>免耕处理,但胞间CO2浓度正好呈现相反规律,翻耕覆膜处理的净光合速率、气孔导度、蒸腾速率分别比翻耕处理、旋耕处理、免耕处理的平均值高出12.81%、30.03%、16.82%,且达显著差异水平(P plowing treatment>rotary tillage treatment>no-tillage treatment,while the intercellular CO2 concentration just right presented a contrary law.The net photosynthetic rate,stomatal conductance and transpiration rate of plowing tillage treatment on an av-erage were higher than that of plowing treatment,rotary tillage,no-tillage by 12.81%,30.03%,16.82% re-spectively,which reached differentially remarkable level (P <0.05).The yield of plowing tillage treatment were higher than that of plowing treatment,rotary tillage treatment,no-tillage treatment by 1 5 .2 1%, 30.82%,31.91% respectively.The average value of grain number per plant,ripe pod per plant,100-grain weight of plowing tillage treatment were higher than that of plowing tillage treatment by 49.27%,48.48%, 14.29%,all of which reached significantly different level.The cultivation of mutiple soybean combined with drip irrigation techniques and farming method of plowing tillage was more advantageous for high yield of summer soybean,under the roughly same conditions with this experimental invironment.

  12. Soil loosening processes in tillage : analysis, systematics and predictability

    NARCIS (Netherlands)

    Koolen, A.J.

    1977-01-01

    The soil movements and the inter-particle forces in the vicinity of an operating tool of a tillage implement may be called a soil tillage process. Examples are the tillage processes of tines, plough-bodies etc. (soil loosening processes) and the influence on the soil of land rollers,

  13. 耕作方式与施肥对陇东旱塬冬小麦-春玉米轮作农田土壤理化性质及产量的影响%Effects of different tillage and fertilization modes on the soil physical and chemical properties and crop yield under winter wheat/spring corn rotation on dryland of east Gansu, Northwest China

    Institute of Scientific and Technical Information of China (English)

    张建军; 王勇; 樊廷录; 郭天文; 赵刚; 党翼; 王磊; 李尚中

    2013-01-01

    Based on the 7-year field experiment on the dryland of east Gansu of Northwest China in 2005-2011, this paper analyzed the variations of soil moisture content, bulk density, and nutrients content at harvest time of winter wheat and of the grain yield under no-tillage and conventional tillage and five fertilization modes, and approached the effects of different tillage and fertilization modes on the soil water storage and conservation, soil fertility, and grain yield under winter wheat/ spring corn rotation. In 2011, the soil moisture content in 0-200 cm layer and the soil bulk density and soil organic matter and available nitrogen and phosphorus contents in 0-20 cm and 20-40 cm layers under different fertilization modes were higher under no-tillage than under conventional tillage. Under the same tillage modes, the contents of soil organic matter and available nitrogen and available phosphorus were higher under the combined application of organic and inorganic fertilizers , as compared with other fertilization modes. The soil available potassium content under different tillage and fertilization modes decreased with years. The grain yield under conventional tillage was higher than that under no-tillage. Under the same tillage modes, the grain yield was the highest under the combined application of organic and inorganic fertilizers, and the lowest under no fertilization. In sum, no-tillage had the superiority than conventional tillage in improving the soil water storage and conservation and soil fertility, and the combined application of organic and inorganic fertilizers under conventional tillage could obtain the best grain yield.%以陇东黄土旱塬已进行7年的田间定位试验为基础,分析了免耕和传统耕作条件下5个施肥处理冬小麦收获期土壤水分、土壤容重(2011年)及土壤养分和产量(2005-2011年)变化,探讨了耕作方式和施肥对冬小麦-春玉米轮作农田土壤蓄水保墒效果及土壤肥力

  14. Sanitary state and yielding of spring barley as dependent on soil tillage method

    Directory of Open Access Journals (Sweden)

    Tomasz P. Kurowski

    2012-12-01

    Full Text Available The effects of traditional tillage cultivation (control treatment, no tillage (instead of tillage the soil was loosened with scruff, and direct sowing (with a special drill into unploughed soil on the health of spring barley cultivar. Klimek were compared in three-field crop rotation (field bean, winter wheat, spring barley in an experiment performed in the years 1997-1999 on the soil of a good wheat complex. The results of phytopathological observations carried out over the vegetation season are presented in the form of an injury index. The following diseases were recorded on spring barley: net blotch (Drechslera teres - net type and spot type, powdery mildew (Blumeria graminis, leaf blotch (Rhynchosporium secalis, eyespot (Tapesia yallundae and foot rot (fungal complex. Tillage system had no a significant influence on the occurrence of both types of net blotch. The intensity of powdery mildew and leaf blotch was the highest in the case of traditional tillage cultivation, and the lowest - in that of no tillage. Direct sowing was conductive to the development of eyespot, and no tillage - to foot rot. Fungi of the genus Fusarium, mainly F. culmorum, and the species Bipolaris sorokiniana, were isolated most frequently from infested stem bases. The weather conditions differed during spring barley grown in the three years analyzed. Mean air temperature in 1997 and 1998 was similar to the many-year average for the city of Olsztyn and its surroundings (13.8°C. In the vegetation season 1999 mean air temperature reached 14.6°C, and was considerably higher than the many-year average. Taking into account total precipitation and distribution in the three-year experimental cycle, 1997 and 1998 can be considered average, and 1999 - wet.The weather conditions had a significant effect on the intensity of all diseases observed on spring barley. The highest yield grain was obtained in the case of traditional tillage cultivation (on average 3.06 t·ha-1 for the

  15. Experiment of "No-Tillage" Farming System on the Volcanic Soils of Tropical Islands of Micronesia

    Directory of Open Access Journals (Sweden)

    Mohammad H. Golabi

    2014-06-01

    The objectives of this study are; 1 to evaluate the use of crop rotation and tillage management for increasing organic-matter content to improve the overall quality of these severely eroded soils, 2 to evaluate the effect of conservation practices on harvested yield and crop productivity of these eroded soils and, 3 to assess the effects of conservation techniques including no-tillage systems on water runoff and infiltration. This paper discusses the effect of conservation strategies and techniques on these severely eroded soils of southern Guam.

  16. [Impact of different tillage practices on soil organic carbon and water use efficiency under continuous wheat-maize binary cropping system].

    Science.gov (United States)

    Ji, Qiang; Sun, Han-Yin; Taraqqi, A K; Wang, Xu-Dong

    2014-04-01

    Base on an 8-year field experiment, the effects of tillage practices coupled with or without straw return on the soil organic carbon (SOC) and water use efficiency (WUE) were investigated in Guanzhong Plain during the growing seasons from 2008 to 2009. The results showed that conservation tillage practices (sub-soiling, SS; rotary tillage, RT; no-till, NT) improved the SOC, WUE and crop yield compared with conventional tillage (CT), among which, SS coupled with straw return had the highest increment, with increase in SOC content of the 0-30 cm soil layer, WUE and crop yield by 19.5%, 16.9% and 20.5%, respectively. The NT practice effectively increased the SOC content of the 0-10 cm soil layer. Conclusively, under the current soil and climatic conditions in Guanzhong Plain, sub-soiling coupled with straw return is the most efficient tillage practice for promoting SOC accumulation, increasing water-use efficiency and yield.

  17. The effects of rape residue mulching on net global warming potential and greenhouse gas intensity from no-tillage paddy fields.

    Science.gov (United States)

    Zhang, Zhi-Sheng; Cao, Cou-Gui; Guo, Li-Jin; Li, Cheng-Fang

    2014-01-01

    A field experiment was conducted to provide a complete greenhouse gas (GHG) accounting for global warming potential (GWP), net GWP, and greenhouse gas intensity (GHGI) from no-tillage (NT) paddy fields with different amounts of oilseed rape residue mulch (0, 3000, 4000, and 6000 kg dry matter (DM) ha(-1)) during a rice-growing season after 3 years of oilseed rape-rice cultivation. Residue mulching treatments showed significantly more organic carbon (C) density for the 0-20 cm soil layer at harvesting than no residue treatment. During a rice-growing season, residue mulching treatments sequestered significantly more organic C from 687 kg C ha(-1) season(-1) to 1654 kg C ha(-1) season(-1) than no residue treatment. Residue mulching significantly increased emissions of CO2 and N2O but decreased CH4 emissions. Residue mulching treatments significantly increased GWP by 9-30% but significantly decreased net GWP by 33-71% and GHGI by 35-72% relative to no residue treatment. These results suggest that agricultural economic viability and GHG mitigation can be achieved simultaneously by residue mulching on NT paddy fields in central China.

  18. Turbulent characteristics of a semiarid atmospheric surface layer from cup anemometers A~é effects of soil tillage treatment (Northern Spain)

    Science.gov (United States)

    Yahaya, S.; Frangi, J. P.; Richard, D. C.

    2003-10-01

    This paper deals with the characteristics of turbulent flow over two agricultural plots with various tillage treatments in a fallow, semiarid area (Central Aragon, Spain). The main dynamic characteristics of the Atmospheric Surface Layer (ASL) measured over the experimental site (friction velocity, roughness length, etc.), and energy budget, have been presented previously (Frangi and Richard, 2000). The current study is based on experimental measurements performed with cup anemometers located in the vicinity of the ground at 5 different levels (from 0.25 to 4 m) and sampled at 1 Hz. It reveals that the horizontal wind variance, the Eulerian integral scales, the frequency range of turbulence and the turbulent kinetic energy dissipation rate are affected by the surface roughness. In the vicinity of the ground surface, the horizontal wind variance logarithmically increases with height, directly in relation to the friction velocity and the roughness length scale. It was found that the time integral scale (and subsequently the length integral scale) increased with the surface roughness and decreased with the anemometer height. These variations imply some shifts in the meteorological spectral gap and some variations of the spectral peak length scale. The turbulent energy dissipation rate, affected by the soil roughness, shows a z-less stratification behaviour under stable conditions. In addition to the characterization of the studied ASL, this paper intends to show which turbulence characteristics, and under what conditions, are accessible through the cup anemometer.

  19. The effect of the glyphosate, 2,4-D, atrazine e nicosulfuron herbicides upon the Edaphic collembola (Arthropoda: Ellipura) in a no tillage system.

    Science.gov (United States)

    Lins, Vilma S; Santos, Honório R; Gonçalves, Manoel C

    2007-01-01

    The use of herbicides is a common and intensive practice in no tillage systems. The herbicides can influence, directly or indirectly, the population of edaphic arthropods. Collembola is a group that functions as a bio-indicator of soil conditions. The degree of abundance and diversity of Collembola provides the level of soil disturbance provoked by agricultural practices. This experiment was designed to compare the influence of herbicides on the population fluctuation of Collembola in a no-till soil preparation system. The work was conducted in a non irrigated no-till area at the Núcleo Experimental de Ciências Agrárias of the Universidade Federal de Mato Grosso do Sul (UFMS), Campus de Dourados, in soil planted with corn as a surface covering, during the period of December, 2002 to December, 2003. The data were analyzed according to a completely randomized model, in a split plot design. The plots received four types of herbicides: glyphosate, atrazine, 2,4-D and nicosulfuron. A fifth plot did not receive any herbicide (control), for a total of five treatment types. The sub plots were represented by their collection times (10, 20, 30 and 40 days after the herbicide applications). Both the type of herbicide and the time of data sampling influenced the Collembola population fluctuaction. The treatments with atrazine and 2,4-D caused the most reduction of the population of Collembola, depending on the time of application.

  20. Seed and Saponin Production of Organic Quinoa (Chenopodium quinoa Willd. for different Tillage and Fertilization

    Directory of Open Access Journals (Sweden)

    Dimitrios BILALIS

    2012-05-01

    Full Text Available Field experiment was conducted to determine the effects of tillage systems and fertilization on growth, yield and quality of quinoa crop (Chenopodium quinoa Willd.. The experiment was laid out in a split-plot design with four replicates, two main plots [conventional tillage (CT and minimum tillage (MT] and three sub-plots (fertilization treatments: control, cow manure and compost. The soil porosity (45.5-49.75% and total nitrogen (0.144-0.173% were higher in soils subjected to MT system than under CT. In soil porosity, an interaction between fertilization and tillage system was found. The highest leaf area index (4.47-5.03, dry weight (8650-9290 kg ha-1 and root density (1.03-1.21 cm cm-3 were also found in MT. Moreover, there were significant differences between the organic fertilization treatments concerning the LAI, dry weight and root density. The highest seed yield (2485-2643 kg ha-1 and saponin content (0.42-0.45% were found in cow manure and compost treatments. Also, the highest saponin yield (7.70-12.05 kg ha-1 was found in the MT system. Saponin yield had positive and significant correlation with total N (r=0.866. In quinoa measurements, an interaction between fertilization and tillage system was not found. The present results indicated that MT and organic fertilization increase saponin yield of quinoa.

  1. INFLUENCE OF SOIL TILLAGE AND LOW HERBICIDE DOSES ON WEED POPULATIONS AND SPRING BARLEY YIELD

    Directory of Open Access Journals (Sweden)

    Mira Knežević

    2003-06-01

    Full Text Available The influence of different tillage variants and low herbicide doses of triasulfuron & chlortoluron mixture (Dicuran forte 80 WP on weed populations and crop yield were studied in spring barley on lessive pseudogley soil in North-Eastern Croatia at the Čačinci locality in 1999. Tillage had no significant influence on annual broad-leaved weed biomass production, which was 22 kg ha-1 , on the average. Chisel ploughing and disk harrowing significantly increased perennial weed biomass by 21 and 44 times, respectively compared to mouldboard ploughing. The average efficacy of total weed biomass control was 95, 89 and 81% at full, onehalf and one-quarter of the recommended herbicide dose, respectively and did not differ very much between tillage treatments. Both reduced herbicide doses ensured very good biomass control of the most abundant weed populations such as Ambrosia artemisiifolia L., Chenopodium album L., Ch. polyspermum L. and Polygonum lapathifolium L. No significant tillage and herbicide dose effects were recorded in barley yields, which ranked from 4.93 t ha-1 in chisel ploughing to 4.48 t ha-1 in disk harrowing. These results suggested a possibility of mouldboard ploughing substitution with reduced tillage practices on lessive pseudogley soil and herbicide dose reduction of triasulfuron & chlortoluron mixture to 50% or more in spring barley.

  2. Cowpea production as affected by dry spells in no-tillage and conventional crop systems

    Directory of Open Access Journals (Sweden)

    Rômulo Magno Oliveira de Freitas

    2013-12-01

    Full Text Available The objective of this study was to evaluate the effect of different periods of water shortage in no-tillage and conventional crop systems on cowpea yield components and grain yield in the Mossoró-RN region. For this, an experiment was conducted using two tillage systems (conventional and no-tillage subjected to periods of irrigation suspension (2; 6; 10; 14; 18 end 22 days, started at flowering (34 days after sowing. Plants were harvested 70 days after sowing, and the studied variables were: Pods length (CV, number of grains per pod (NGV, number of pods per plant (NPP, the hundred grains weight (PCG and grain yield (kg ha-1. The no-tillage system is more productive than the conventional under both irrigation and water stress treatments. The water stress length affected grain yield and all yield components studied in a negative way, except for the hundred grains weight. Among the systems studied, the no-tillage provides higher values for the yield components, except the hundred grains weight.

  3. Influence of soil tillage and weed suppression on winter wheat yield

    Directory of Open Access Journals (Sweden)

    Mikić Branimir M.

    2011-01-01

    Full Text Available Modern soil tillage systems based on different tools than mouldboard plough have very often stronger weed occurrence, which can be a serious problem for achieving high yields. An obvious solution for weed suppression is a herbicide, whose improper use can deteriorate environment and lead toward serious ecological problems. In order to investigate the interaction between soil tillage and herbicide, trial was set up in Valpovo in seasons 2008/09 - 2010/11. Two soil tillage systems (CT-conventional tillage, based on mouldboard ploughing, and CH-chiselling and disk harrowing, without ploughing and five herbicide treatments (NH-control, no herbicides; H10- recommended dose of Herbaflex (2 l ha-1; H05-half dose of Herbaflex; F10- recommended dose of Fox (1.5 l ha-1; and F05-half dose of Fox were applied to winter wheat crops. Results showed similar effects of soil tillage on the winter wheat yield, whereas different herbicide dosages showed similar weed suppression and influence on winter wheat yield.

  4. Macro- and microscale gaseous diffusion in a Stagnic Luvisol as affected by compaction and reduced tillage

    Directory of Open Access Journals (Sweden)

    A. SIMOJOKI

    2008-12-01

    Full Text Available Intensification of mechanical agriculture has increased the risk for soil compaction and deformation. Simultaneously, reduced tillage practices have become popular due to energy saving and environmental concerns, as they may strengthen and improve the functioning of structured soil pore system. Soil aeration is affected by both compaction and reduced tillage through changes in soil structure and in the distribution of easily decomposable organic matter. We investigated whether a single wheeling by a 35 000 kg sugar-beet harvester in a Stagnic Luvisol derived from loess near Göttingen, Germany, influenced the gas transport properties (air permeability, gaseous macro- and microdiffusivities, oxygen diffusion rate in the topsoil and subsoil samples, and whether the effects were different between long-term reduced tillage and mouldboard ploughing. Poor structure in the topsoil resulted in slow macro- and microscale gas transport at moisture contents near field capacity. The macrodiffusivities in the topsoil under conventional tillage were slower compared with those under conservation treatment, and soil compaction reduced the diffusivities by about half at the soil depths studied. This shows that even one pass with heavy machinery near field capacity impairs soil structure deep into the profile, and supports the view that reduced tillage improves soil structure and aeration compared with ploughing, especially in the topsoil.;

  5. A multiple soil ecosystem services approach to evaluate the sustainability of reduced tillage systems

    Science.gov (United States)

    Pérès, Guénola; Menasseri, Safya; Hallaire, Vincent; Cluzeau, Daniel; Heddadj, Djilali; Cotinet, Patrice; Manceau, Olivier; Pulleman, Mirjam

    2017-04-01

    reduced tillage systems improved soil ecosystem services such as soil biodiversity, water regulation (quantity, quality), carbon storage and soil stability; however, the effects on crop production were more variable (-10% to +7 % range), strongly depending on crop type and agricultural practices (fertilisation, rotation, cover crop). Sociological approach showed that saving labour time and fuel costs were the main motivations for change. Agronomic and environmental benefits are not the trigger but are increasingly recognized and contribute to the maintenance of the practice. Farmers also expressed a need for stronger networking and technical advice, which plays a crucial role. Scientists and experts raise awareness, support collective learning and provide instrumental. Recommendations were provided for sustainable soil management aiming at ecological intensification of agricultural land.

  6. Repeated soil application of organic waste amendments reduces draught force and fuel consumption for soil tillage

    DEFF Research Database (Denmark)

    Peltrea, Clément; Nyord, Tavs; Bruun, Sander

    2015-01-01

    for different organic wastes influenced the specific draught. Overall, the decrease in draught force could lead to a decrease in tractor fuel consumption for soil tillage of up to 25% for compost applied at an accelerated rate and up to 14% for compost applied at a normal rate. This reduced fuel consumption......Abstract Soil application of organic waste products (OWP) can maintain or increase soil organic carbon (SOC) content, which in turn could lead to increased porosity and potentially to reduced energy use for soil tillage. Only a few studies have addressed the effect of SOC content on draught force...... for soil tillage, and this still needs to be addressed for fields that receive diverse types of organic waste of urban, agricultural and agro-industrial origin. The objective of this study was to determine the effect of changes in SOC induced by repeated soil application of OWP on draught force for soil...

  7. 小麦、玉米轮作制度下耕作方式对夏玉米农田土壤物理性状的影响%Effects of Tillage Managements in Wheat-maize Crop System on Soil Physical Properties in Summer Maize Season

    Institute of Scientific and Technical Information of China (English)

    刘淑梅; 曲晓燕; 张洪生; 姜雯

    2013-01-01

    将冬小麦、夏玉米作为整体,研究耕作定位试验(10种不同耕作措施)对山东省半湿润易旱区夏玉米季土壤物理性状的影响。耕作试验(第2年)结果表明:与玉米吐丝期和灌浆中期相比,收获期土壤含水量受耕作方式影响更显著,其中土壤表层0~20 cm土层土壤含水量最高,耕作处理为A2 B2 R(小麦季免耕+玉米季免耕+秸秆还田),20~40 cm、40~60 cm均为A1 B2 R(小麦季旋耕+玉米季免耕+秸秆还田)最高。玉米吐丝期和收获期各土层温度均值(上午8时)为A3 B2 R(小麦季深松+玉米季免耕+秸秆还田)和A1 B1 R(小麦季旋耕+玉米季隔年旋耕+秸秆还田)耕作方式土壤温度最高,比对照(小麦季旋耕+玉米季免耕+秸秆不还田)增加0.4~0.6℃。处理A1 B2 R、A2 B2 R和A4 B2 R(小麦季深耕+玉米季免耕+秸秆还田)表层0~20cm土壤容重显著降低;小麦季深松和深耕( A3 B2 R、A4 B2 R)和小麦、玉米两季均深耕或深松(A3B3R、A4B4R)显著降低深层(40~60 cm)土壤容重,尤其是小麦、玉米两季均深耕或深松。因此小麦、玉米两季均免耕能显著降低表层土壤容重,增加表层含水量;而深耕、深松耕作方式主要影响深耕层土壤容重,其中小麦季、玉米季两季均深松或深耕效果好于小麦单季深松或深耕。%During wheat-maize whole season ,with ten different tillage treatments ,the effects of tillage manage-ments on soil physical properties in summer maize season were studied .Compared with silking and mid-filling stage , the soil water content was more largely affected by tillage treatments ,and the highest water content in the layer be-tween 0-20 cm was found in A2B2R(No-tillage at either wheat season or at maize season +straw returning),and the highest water content in both 20-40 and 40-60cm were in A1B2R(Rotary tillage at wheat season

  8. Minidisk against ring infiltrometer measurements to assess the saturated hydraulic conductivity in Mediterranean vineyards (Vitis vinifera L.) under Tillage and No-Tillage managements

    Science.gov (United States)

    Burguet, Maria; Di Prima, Simone; Prosdocimi, Massimo; Taguas, Encarnación V.; Cerdà, Artemi

    2016-04-01

    Vineyard is one of the main crops in the Mediterranean region and it forms, along with wheat and olive, what it is known as the 'Mediterranean triad'. According to the Food and Agriculture Organization of the United Nations (FAO, 2010), the European Union has 4.5 million hectares of land occupied by vineyards. Out of all, the Mediterranean region has the largest total area of vineyards. France, Italy and Spain together are responsible for 48% of global wine production. In Spain, the total surface occupied by vineyards is 1.048.104 ha (Ministry of Agriculture, Food and Environment, 2009), which is translated in a 13% of world total (Wine Institute, 2014). In terms of environmental factors, vineyards are a source of sediments and water due to the tillage and the soil compaction, the lack of vegetation cover and the soil organic matter depletion (Novara et al., 2011; Lieskovsky' et al., 2014; Rodrigo Comino et al., 2015). The infiltration capacity of soils is a key component of the hydrological cycle that can control the non-sustainable rates of runoff and erosion (Cerdà, 1997,1999). In this way research focused on the soil hydrological properties will bring knowledge on how to control the high erosion rates (Cammeraat et al., 2010). Saturated hydraulic conductivity, ks, is the most determining physical parameter in terms of quantifying the components of the global water balance as it interferes in all those processes which are related with water and solute movement and transport through the soil. ks values are required for an adequate modelling of the infiltration and runoff generation processes. However, it is a variable with high variability when it comes to agricultural soils due to different soil managements and the fact that the soil is not a continuous media (Polo et al., 2003). For instance, Leonard and Andrieux (1998) reported in a study done in untilled vineyards in France high differences in infiltration rates through the use of rainfall simulations, which

  9. Efeito de três sistemas de preparo do solo sobre a rentabilidade econômica da mandioca (Manihot esculenta Crantz = Effects of three tillage systems on economic profitability of cassava crop (Manihot esculenta Crantz

    Directory of Open Access Journals (Sweden)

    Manoel Genildo Pequeno

    2007-07-01

    Full Text Available O objetivo deste estudo foi avaliar a rentabilidade econômica da cultura damandioca em três sistemas de preparo de solo durante os anos agrícolas de 1999/2000 a2002/2003, em Araruna, Estado do Paraná. O delineamento experimental utilizado foi o deblocos completos casualizados, com oito repetições. Os tratamentos foram constituídos deplantio direto; preparo mínimo (escarificação e preparo convencional (aração + gradagemniveladora. A força de tração e o consumo de combustível requeridos nas operações depreparo do solo e de plantio da mandioca foram maiores no sistema de preparoconvencional. Os maiores custos com combustível, preparo do solo e plantio da mandioca, ecusto operacional relativo às culturas de inverno e à cultura da mandioca, bem como a maiorrenda bruta foram observados no sistema de preparo convencional, seguidos pelo preparomínimo e plantio direto. A maior renda líquida e a melhor relação benefício/custo foramobservadas no sistema de preparo convencional que proporcionou maior produtividade deraízes tuberosas em relação aos sistemas de preparo mínimo e de plantio direto.The objective of this paper was to evaluate the economicprofitability of cassava crop submitted to the three soil tillage systems during the years1999/2000 to 2002/2003, in Araruna, state of Parana. The treatments consisted of three soiltillage systems: no-tillage, minimum tillage using chiseling, and conventional tillage withmoldboard plow and disking, arranged in a randomized complete blocks with eightreplications. The traction strength and fuel consumption in the soil tillage and in the cassavasowed operation were more required in the conventional tillage system. The conventionaland the minimum tillage systems showed the highest costs for fuel, soil tillage and cassavasowed. They also presented the highest gross income. The greatest net income and the bestbenefit/cost relation were observed in the conventional tillage system, which

  10. Effect of Fixed Centroid Line on the Performance of Soil Throw Through Reverse Rotary Tillage%不动形心线对逆转耕耘抛土性能的影响

    Institute of Scientific and Technical Information of China (English)

    刘永清; 宋志禹

    2016-01-01

    Based on the analysis of reverse rotary work , the effect of the fixed centroid line ( FCL) line effect on the re-versal rotary work was proposed .A detailed analysis of the regulation of FCL effect was given in the reverse rotary blade moving track , reverse rotary cutting angle and reverse rotary tillage backward throw of soil , and a model for instantaneous velocity direction at the beginning of soil throwing of reverse rotary is established , and the model is simulated .It provides a reference basis for the design of tillage machine in tea garden .The main conclusion: The rotary tillage can work nor-mally only when the FCL distance is less than the rotary shaft radius , and FCL which located above rotary shaft is for re-verse rotary work mode , FCL which located below rotary shaft is for forward rotary work mode .In reverse rotary mode , when the blade running to FCL , dynamic cutting angle will be minimum .Only when FCL is located above reverse rotary shaft and located below the ground surface , it will has backward throw of soil .%在分析逆转旋耕工作的基础上,提出了不动形心线( Fixed Centroid Line-FCL )对逆转耕耘方式影响的思想。在旋耕刀片运动轨迹、逆转旋耕切削角度及逆转旋耕抛土后向性等方面,详细分析了 FCL 线的影响性质,建立了逆转旋耕被抛土垡瞬时初速度的方向模型,并对模型进行了仿真,为茶园耕作机械的设计提供了参考依据。主要结论:FCL 线距刀辊轴的距离小于刀辊回转半径时,旋耕刀片才能够正常工作,且 FCL 线位于刀辊轴的上方为逆转耕耘方式,位于刀辊轴的下方为正转耕耘方式;在逆转旋耕方式下,当刀片运转到 FCL 线时,动态切土角最小;当FCL 线位于刀辊轴之上,且同时又在地表之下时,逆转旋耕才具有抛土后向性。

  11. Effects of mulching with no-tillage on soil physical properties and potato yield in mountain area of southern Ningxia%免耕覆盖对宁南山区土壤物理性状及马铃薯产量的影响

    Institute of Scientific and Technical Information of China (English)

    侯贤清; 李荣

    2015-01-01

    宁南山区干旱频发、春旱突出,马铃薯播期土壤墒情不足、苗期干旱等问题,严重影响马铃薯的生长发育。该研究通过设置免耕条件下不同覆盖方式,以翻耕不覆盖为对照,研究不同覆盖耕作措施下土壤物理性状及马铃薯生长的影响。结果表明,与翻耕不覆盖相比,免耕覆盖可有效降低耕层土壤容重,改善土壤空隙状况,以免耕覆盖秸秆处理效果最佳。与翻耕不覆盖相比,免耕覆盖地膜和免耕覆盖秸秆处理可使0~20 cm土层>5 mm机械稳定性团聚体含量显著增加,使>20~40 cm土层2~5 mm机械稳定性团聚体的含量显著增加。免耕条件下不同覆盖方式能有效改善马铃薯生育期0~200 cm土层土壤水分状况,免耕覆盖地膜对作物生长前期土壤水分保蓄效果较好,免耕覆盖秸秆对作物生长中后期土壤水分状况的改善作用最佳。免耕条件下不同覆盖方式马铃薯植株株高、茎粗及地上部生物量均显著高于翻耕不覆盖,作物生育前期以免耕覆地膜处理效果最佳,中后期以免耕覆秸秆处理效果最明显。免耕覆秸秆处理的马铃薯产量和商品薯率最高,较翻耕不覆盖增产24.14%,商品薯率较翻耕不覆盖提高15.93%。可见,免耕覆盖秸秆措施具有良好的蓄水保墒效果,对马铃薯生长有利,其增产效果显著。该研究可为马铃薯高产高效栽培提供参考。%Droughts often occur, particularly in spring in southern mountainous region of Ningxia. The problem of soil water shortage and drought in seedling stage seriously influence the growth and yield of potato. In order to explore the effects of different ground surface methods combined with no tillage on soil physical characteristics, potato growth, and yield, a 3-year field experiment was conducted to study the effect of mulching with tillage on soil bulk density, elastic-stable aggregate, soil water

  12. Effect of No-tillage on Fluvor-Aquic Soil Carbon Pool in North China%免耕对华北地区潮土碳库特征的影响

    Institute of Scientific and Technical Information of China (English)

    姜学兵; 侯瑞星; 李运生; 欧阳竹; 张妍; Wilson V.Glenn; 李汉侠

    2012-01-01

    以实施7年的中国科学院禹城综合试验站冬小麦-夏玉米轮作免耕长期定位试验场为对象,系统研究免耕条件下土壤总碳(TC)、有机碳(SOC)、无机碳(SIC)的变化,为进一步评价免耕措施对华北地区潮土碳库的影响提供数据支持。研究设置免耕秸秆覆盖(NTRC)、免耕施用有机肥(NTRR)、常规耕作(CT)3种处理,分析表层(0-20cm)及深层(20-60cm)土壤TC、SOC及SIC的变化特征和影响因素。主要结果为:NTRC和NTRR能够增加0-20cm土层TC含量及储量,但降低20-60cm土层TC含量及储量,0-60cm总碳储量表现为NTRC〉CT〉NTRR;与CT相比,NTRC能够显著增加0-20cm而降低20-60cm土层SOC含量及储量,NTRR增加了0-5cm土层SOC含量及储量,在5-60cm则呈降低趋势,0-60cm土层SOC储量表现为CT〉NTRC〉NTRR;NTRC增加了0-60cm土层SIC储量,而NTRR则影响较小。TC与SOC呈显著正相关(P〈0.05),而与SIC呈显著负相关(P〈0.05),说明总碳的变化趋势与SOC一致,与SIC相反。%To further understand the effect of no-tillage (NT) on soil carbon pool in north China plain, the contents of soil total carbon, soil organic carbon and inorganic carbon under three different tillage systems for seven years at Yucheng Comprehensive Experimental Station, Chinese Academy of Sciences, which is a long- term no-tillage experimental site for the main crop rotation-winter wheat(Triticum aestivum L. ) and summer maize(Zea mays L. ), were investigated. No-tillage with residue cover(NTRC), no-tillage with residue re- moved and organic fertilization(NTRR) and conventional tillage(CT) treatments were set up. In addition, relationships among TC, SOC, SIC, pH, bulk density, MWD and GMD were analyzed. In comparision with CT treatment, total carbon stock increased in top soil(0--20 cm), but decreased in deep soi1(20--60 cm) in both NTRC and NTRR treatments. The storage of TC in 0--60 cm soil

  13. Tillage impact on herbicide loss by surface runoff and lateral subsurface flow.

    Science.gov (United States)

    Potter, Thomas L; Bosch, David D; Strickland, Timothy C

    2015-10-15

    There is worldwide interest in conservation tillage practices because they can reduce surface runoff, and agrichemical and sediment losses from farm fields. Since these practices typically increase infiltration, their use may increase subsurface transport of water-soluble contaminants. Thus, to assess long-term environmental benefits of conservation tillage data may be needed that quantify both surface and subsurface contaminant fluxes. This study focused on the herbicide fluometuron (N,N-dimethyl-N'-[3-(trifluoromethyl)phenyl]-urea) and its soil degradate DMF (N-methyl-N'-[3-(trifluoromethyl) phenyl]-urea). Both compounds are classed as "leachable". They were measured for 10 years in surface runoff and lateral subsurface flow from paired fields located on a hill slope in the Atlantic Coastal Plain region of the southeastern USA. One group of fields was conventionally tilled incorporating all crop residues into soil prior to planting. The second was strip tilled, a common conservation tillage practice. Seven fluometuron applications were made to cotton (Gossypium hirsutum) produced in rotation with peanut (Arachis hypogea). Combined fluometuron and DMF surface and subsurface losses from the conventionally tilled fields were equivalent to 1.2% and 0.13% of fluometuron applied and 0.31% and 0.32% from the strip tilled fields. Annual surface runoff losses were significantly greater from the conventionally tilled fields while the strip tilled fields had significantly greater annual subsurface losses. Results demonstrated that shifting from conventional to conservation tillage management of farm fields in this landscape will reduce surface runoff losses of herbicides like fluometuron but subsurface losses will likely increase. The same trends can be expected in landscapes with similar soil and hydrologic properties. This should be considered when planning implementation of programs that promote conservation tillage use.

  14. Effects of Different Tillage Methods on Chilling Resistance of Maize%不同耕作方法条件下玉米抗御低温冷害的研究

    Institute of Scientific and Technical Information of China (English)

    王俊国

    2008-01-01

    [Objective] Aiming at chilling damage of maize in lowland of western Liaoning, the powerful evidences of resisting chilling damage of maize were provided from tillage method perspective.[Method] The depths of plough layers, sunshine effects in seedling stage, resistances to frost damage, microclimatic effects such as soil moisture, root system in filling stage, growth periods and grain weights of maize planted on ridge and in furrow were comparatively observed. The random arrangement was adopted in comparative observation with 4 replications.[Result] The daily mean ground temperature and effective accumulated temperature of plough layer of maize planted on ridge were relatively high. In addition, the seedling stage and mature stage of maize planted on ridge were in advance, the soil moisture, root growth and seed plumpness of maize planted on ridge were good. [Conclusion] The ridge planting in lowland of western Liaoning could improve in 0-20 cm plough layer where root grew, besides that this method could also improve maize growth and development.

  15. Tillage management to mitigate herbicide loss in runoff under simulated rainfall conditions.

    Science.gov (United States)

    Locke, Martin A; Zablotowicz, Robert M; Reddy, Krishna N; Steinriede, R Wade

    2008-02-01

    Conservation tillage mitigates soil loss in cropland because plant residues help protect the soil, but effects on pesticide movement in surface runoff are not as straightforward. Effects of soil disturbance on surface runoff loss of chlorimuron and alachlor were evaluated utilizing runoff trays. Soil in the trays was either disturbed (tilled) and kept bare or was not tilled, and existing decomposed plant residue was left on the surface. Rainfall (25mm, 20min) was simulated 1d after alachlor (2.8kg ha(-1)) or chlorimuron (54g ha(-1)) application, and runoff was collected. Runoff fractions were analyzed for herbicide and sediment. Total alachlor loss from bare plots was greater than that in no-tillage plots (4.5% vs. 2.3%, respectively). More than one-third of total alachlor lost from bare plots occurred in the first l of runoff, while no-tillage plots had less runoff volume with a more even distribution of alachlor concentration in the runoff during the rainfall simulation and subsequent runoff period. In contrast, more chlorimuron was lost from no-tillage plots than bare plots (12% vs. 1.5%) even though total runoff volume was lower in the no-tillage plots (10.6mm vs. 13.6mm). This was attributed to dense coverage with partially decomposed plant residue in no-tillage plots (1652kg ha(-1)) that intercepted chlorimuron. It was likely that chlorimuron, a polar compound, was more easily washed off surface plant residues and transported in runoff.

  16. Water Availability for Winter Wheat Affected by Summer Fallow Tillage Practices in Slope Dryland

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-bin; YANG Bo; Roger Hartmann; Donald Gabriels; CAI Dian-xiong; JIN Ke; WU Hui-jun; BAI Zhan-guo; ZHANG Can-jun; YAO Yu-qing; LU Jun-jie; WANG Yu-hong

    2003-01-01

    The tillage experiments for winter wheat were conducted on the slope farmland in Luoyang,Henan Province in the semihumid to arid loess plateau areas of North China. Different tillage methods inclu-ding reduced tillage (RT), no-till (NT), 2 crops/year (2C), subsoiling(SS), and conventional tillage (CT)were compared to determine the effects of tillage methods on soil water conservation, water availability, andwheat yields in a search for better farming systems in the areas. The NT and SS showed good effects on waterconservation. The soil water storage increased 12 - 33 mm with NT and 9 - 24 mm with SS at the end of sum-mer fallow periods. The soil evaporation with NT and SS decreased 7 - 8 mm and 34 - 36 mm during the fallowperiods of 1999 and 2001, respectively. Evapotranspiration (ET) with NT and SS increased about 47 mm dur-ing wheat growth periods of 2000 to 2001. Treatment RT and 2C had low water storage and high water lossesduring the fallow periods. The winter wheat yields with conservation tillage practices were improved in the 2ndyear, increased by 3, 5 and 8 % with RT, NT and SS, respectively, compared with CT. The highest wheatyields were obtained with subsoiling, and the maximum economic benefits from no-till. All conservation tillagepractices provided great benefits to saving energy and labors, reducing operation inputs, and increasing eco-nomic returns. No-till and subsoiling have shown promise in increasing water storage, reducing water loss, en-hancing water availability, and saving energy, as well as increasing wheat yield.

  17. Soil properties and crop yield under different tillage methods for rapeseed cultivation in paddy fields

    Directory of Open Access Journals (Sweden)

    Alizadeh Mohammad Reza

    2015-01-01

    Full Text Available A two-year research was conducted to investigate the effect of different tillage methods on some soil physical characteristics and crop yield in rapeseed cultivation after rice harvesting. Five tillage treatments including: (i using rotavator, once to depth of 10-15 cm (T1, (ii using rotavator, twice to depth of 10-15 cm (T2, (iii using moldboard plow to depth of 25 cm + rotavator, once to depth of 10-15 cm (T3, (iv no-till planting through removing rice stubbles from plots (T4, and (v no-till planting without removing rice stubbles from plots (T5, were evaluated under randomized complete block design (RCBD in three replications. The biannual results revealed that the effect of tillage methods was significant (p<0.01 on soil bulk density, surface residues after tillage, dry mass of weeds, seed germination, and grain yield. T2 and T3 made considerable reduction in soil bulk density compared to other treatments for the 15- to 30-cm tillage depths. In T1, T2, T3, and T4, surface residues after tillage decreased in comparison with T5 by up to 35.37, 50.71, 69.92, and 75.75%, respectively. Having 71.48 g m-2, T5 had the maximum dry mass of weeds while T3 had the minimum one with 37.50 g m-2. Means comparison represented that in T2 and T3, seed germination reached the shortest length of 6.4 days in average. The highest and lowest grain yields were acquired in T3 (1,571 kg ha-1 and T5 (1,339 kg ha-1, respectively. Statistically, there was no significant difference between T1 (1,432 kg ha-1 and T2 (1,537 kg ha-1 compared with T3 in terms of grain yield.

  18. European Perspectives on the Adoption of Nonchemical Weed Management in Reduced -Tillage Systems for Arable Crops

    DEFF Research Database (Denmark)

    Melander, Bo; Munier-Jolain, Nicolas; Charles, Raphaël

    2013-01-01

    to allow for more diversification of the crop rotations to combat these weed problems with less herbicide input. Cover crops, stubble management strategies and tactics that strengthen crop growth relative to weed growth are also seen as important components in future IPM systems but their impact in non......-inversion tillage systems needs validation. Direct mechanical weed control methods based on rotating weeding devices such as rotary hoes may become useful in reduced tillage systems where more crop residues and less workable soils are more prevalent but further development is needed for effective application. Owing...

  19. Relations between soil surface roughness, tortuosity, tillage treatments, rainfall intensity and soil and water losses from a red yellow latosol

    Directory of Open Access Journals (Sweden)

    Julieta Bramorski

    2012-08-01

    Full Text Available The soil surface roughness increases water retention and infiltration, reduces the runoff volume and speed and influences soil losses by water erosion. Similarly to other parameters, soil roughness is affected by the tillage system and rainfall volume. Based on these assumptions, the main purpose of this study was to evaluate the effect of tillage treatments on soil surface roughness (RR and tortuosity (T and to investigate the relationship with soil and water losses in a series of simulated rainfall events. The field study was carried out at the experimental station of EMBRAPA Southeastern Cattle Research Center in São Carlos (Fazenda Canchim, in São Paulo State, Brazil. Experimental plots of 33 m² were treated with two tillage practices in three replications, consisting of: untilled (no-tillage soil (NTS and conventionally tilled (plowing plus double disking soil (CTS. Three successive simulated rain tests were applied in 24 h intervals. The three tests consisted of a first rain of 30 mm/h, a second of 30 mm/h and a third rain of 70 mm/h. Immediately after tilling and each rain simulation test, the surface roughness was measured, using a laser profile meter. The tillage treatments induced significant changes in soil surface roughness and tortuosity, demonstrating the importance of the tillage system for the physical surface conditions, favoring water retention and infiltration in the soil. The increase in surface roughness by the tillage treatments was considerably greater than its reduction by rain action. The surface roughness and tortuosity had more influence on the soil volume lost by surface runoff than in the conventional treatment. Possibly, other variables influenced soil and water losses from the no-tillage treatments, e.g., soil type, declivity, slope length, among others not analyzed in this study.

  20. A comparison of dissolved inorganic nitrogen, chloride and potassium loss in conventional and conservation tillage

    Science.gov (United States)

    Tillage impact on dissolved losses of ammonium (NH4-N) and nitrate nitrogen (NO3-N), chloride (Cl), and potassium (K) during rotational cotton and peanut production was evaluated. Tillage treatments were strip-tillage (ST) and conventional-tillage (CT). Winter cover crops were used in both tillage...

  1. 黄土区坡耕地耕作对浅沟径流产沙及其形态发育特征的影响%Effect of tillage on runoff and sediment yields and morphology development characteristic of ephemeral gully in loessial region

    Institute of Scientific and Technical Information of China (English)

    郭明明; 王文龙; 李建明; 朱宝才; 史倩华; 康宏亮; 李艳富; 李垚林

    2015-01-01

    In the hill-gully area of the Loess Plateau, serious man-made soil and water loss occurs in disturbed soils of sloping farmlands formed in the process of tillage operation. Frequent farming activities cause ephemeral gullies to develop continuously on sloping farmlands. Although an ephemeral gully may be refilled and rehabilitated, new ephemeral gully may develop in the original position in next rainy season. An indoor flow scouring experiment under artificially simulated rainfall was carried out in the State Key Laboratory of Soil Erosion and Dryland Agriculture on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, China in July 2014. The effects of tillage treatments on runoff and sediment yielding in ephemeral gully and its morphology were investigated at different rainfall intensities and slope degrees under the condition of upslope concentrated flow. Based on preliminary field investigations, 3 slope degrees of 15°, 20° and 25° were selected. Rainfall intensity was designed at 1.0, 1.5, and 2.0 mm/min. Flow discharges were 7.53 to 23.45 L/min. Plots of 8 m×1m were laid out for experiments and 3 flow sections were set up for runoff and sediment measurements. Before each test, rainfall intensity was calibrated repeatedly until the rainfall uniformity coefficient reached 85% or above. During each test, flow velocity was measured with dye tracing method and flow width and depth were measured with point gauge system. Runoff sample was taken once a minute within 3 minutes before runoff generation, and once 3 minutes after runoff generation. The results showed that: 1) Flow regimes for non-tilled and tilled ephemeral gullies were characterized by turbulent flow; Tillage could decrease Reynolds number and Froude number by 0.95%-30.77% and 3.41%-35.66%, and increase Darcy-Weisbachcoefficient and Manning roughness coefficient by 4.01%-58.82% and 0.88%-27.87%, respectively; and 2) Compared to non

  2. Dryland malt barley yield and quality affected by tillage, cropping sequence, and nitrogen fertilization

    Science.gov (United States)

    Information is needed on the effects of management practices on dryland malt barley (Hordeum vulgaris L.) and pea (Pisum sativum L.) yields and quality. We evaluated the effects of tillage and cropping sequence combination and N fertilization on dryland malt barley and pea yields, grain characterist...

  3. Soil and crop residue CO2-C emission under tillage systems in sugarcane-producing areas of southern Brazil

    Directory of Open Access Journals (Sweden)

    Luís Gustavo Teixeira

    2013-10-01

    Full Text Available Appropriate management of agricultural crop residues could result in increases on soil organic carbon (SOC and help to mitigate gas effect. To distinguish the contributions of SOC and sugarcane (Saccharum spp. residues to the short-term CO2-C loss, we studied the influence of several tillage systems: heavy offset disk harrow (HO, chisel plow (CP, rotary tiller (RT, and sugarcane mill tiller (SM in 2008, and CP, RT, SM, moldboard (MP, and subsoiler (SUB in 2009, with and without sugarcane residues relative to no-till (NT in the sugarcane producing region of Brazil. Soil CO2-C emissions were measured daily for two weeks after tillage using portable soil respiration systems. Daily CO2-C emissions declined after tillage regardless of tillage system. In 2008, total CO2-C from SOC and/or residue decomposition was greater for RT and lowest for CP. In 2009, emission was greatest for MP and CP with residues, and smallest for NT. SOC and residue contributed 47 % and 41 %, respectively, to total CO2-C emissions. Regarding the estimated emissions from sugarcane residue and SOC decomposition within the measurement period, CO2-C factor was similar to sugarcane residue and soil organic carbon decomposition, depending on the tillage system applied. Our approach may define new emission factors that are associated to tillage operations on bare or sugarcane-residue-covered soils to estimate the total carbon loss.

  4. Production and efficiency of water usage in capsicum crops under no-tillage and conventional planting systems

    Directory of Open Access Journals (Sweden)

    Maria Eliani Holanda Coelho

    Full Text Available This study aimed to evaluate the effect of no-tillage and conventional planting systems, and of weed-management strategies on water-usage efficiency in capsicum crops. The experiment was carried out at the Universidade Federal Rural do Semi-Árido in Mossoró, Rio Grande do Norte, using a split-plot layout in a randomized block design with four replications. The tillage systems were evaluated in the plots, and three weed-management strategies evaluated in the subplots (soil cover with polyethylene film, and with and without weeds. The density and dry mass of the weeds, the commercial and total productivity, and the daily water consumption were all evaluated. It was found that the no-tillage system reduced the density and dry mass of the weeds in comparison to conventional systems, and the interference of these plants reduced commercial productivity under both planting systems. The strategy of weeds under a no-tillage system, despite a higher water consumption, showed a productivity and efficiency of water usage superior to those of the strategies of polyethylene film both under no-tillage and conventional systems, and of weeds under a conventional tillage system.

  5. Impact of Tillage and Fertilizer Application Method on Gas Emissions in a Corn Cropping System

    Institute of Scientific and Technical Information of China (English)

    K. SMITH; D. WATTS; T. WAY; H. TORBERT; S. PRIOR

    2012-01-01

    Tillage and fertilization practices used in row crop production are thought to alter greenhouse gas ernissions from soil.This study was conducted to determine the impact of fertilizer sources,land management practices,and fertilizer placement methods on greenhouse gas (CO2,CH4,and N2O) emissions.A new prototype implement developed for applying poultry litter in subsurface bands in the soil was used in this study.The field site was located at the Sand Mountain Research and Extension Center in the Appalachian Plateau region of northeast Alabama,USA,on a Hartsells fine sandy loam (fine-loamy,siliceous,subactive,thermic Typic Hapludults).Measurements of carbon dioxide (CO2),methane (CH4),and nitrous oxide (N2O) emissions followed GRACEnet (greenhouse gas reduction through agricultural carbon enhancement network) protocols to assess the effects of different tillage (conventional vs.no-tillage) and fertilizer placement (subsurface banding vs.surface application) practices in a corn (Zea mays L.) cropping system.Fertilizer sources were urea-ammonium nitrate (UAN),ammonium nitrate (AN) and poultry litter (M) applied at a rate of 170 kg ha -1 of available N.Banding of fertilizer resulted in the greatest concentration of gaseous loss (CO2 and N2O) compared to surface applications of fertilizer.Fertilizer banding increased CO2 and N2O toss on various sampling days throughout the season with poultry litter banding emitting more gas than UAN banding.Conventional tillage practices also resulted in a higher concentration of CO2 and N2O loss when evaluating tillage by sampling day.Throughout the course of this study,CH4 flux was not affected by tillage,fertilizer source,or fertilizer placement method.These results suggest that poultry litter use and banding practices have the potential to increase greenhouse gas emissions.

  6. Tillage as a tool to manage crop residue: impact on sugar beet production.

    Science.gov (United States)

    Hiel, Marie-Pierre; Chélin, Marie; Degrune, Florine; Parvin, Nargish; Bodson, Bernard

    2015-04-01

    Crop residues and plant cover represent a pool of organic matter that can be used either to restore organic matter in soils, and therefore maintain soil fertility, or that can be valorized outside of the field (e.g. energy production). However, it is crucial that the exportation of residues is not done to the detriment of the system sustainability. Three long term experiments have been settled in the loamy region in Belgium. All of them are designed to study the effect of residues management by several tillage systems (conventional plowing versus reduced tillage) on the whole soil-water-plant system. SOLRESIDUS is a field experiment where we study the impact of crop residue management while in SOLCOUVERT and SOLCOUVERT-BIS, we study the impact of cover crop management. SOLRESIDUS was started in 2008. In this field, four contrasted crop residues managements are tested in order to contrast as much as possible the responses from the soil-water plant system. Two practices characterize the four modalities: soil tillage (ploughing at 25 cm depth or reduce tillage at 10 cm max) and residue management (exportation or restitution). SOLCOUVERT and SOLCOUVERT-BIS were started in 2012 and 2013 respectively. In those fields cover crop management is also diverse: destruction of the cover crop by winter ploughing, spring ploughing, strip tillage (with a chemical destruction if needed) or shallow tillage (with a decompaction before cover crop sowing). Although although the overall project aims at studying the impact of management on the whole soil-water-plant system, here we will only present the results concerning crop production (sugar beet) in SOLCOUVERT experiments. The presented data will include germination rate, crop development (biomass quantification and BBCH stages) weeds population, disease occurrence, pest occurrences, nitrogen uptake by plants, quality and quantity of harvested products.

  7. Soil microbial biomass alterations during the maize silage growing season relative to tillage method

    Energy Technology Data Exchange (ETDEWEB)

    Staley, T.E.

    1999-12-01

    Tillage method can significantly alter soil microbial populations and activities. Although considerable literature exists on microbial and soil chemical alterations under various tillage methods, little information exists on soil microbial biomass C (SMB) alterations during the growing season, and especially on the relationship of SMB to crop N use. The objective of this study was to determine the effect of notillage (NT) or conventional tillage (CT), and soil location, on SMB during the growing season. A maize (Zea mays L.) silage/{sup 15}N field experiment, under NT or CT for 3 yr before this study, was used during the fourth growing season. Averaged over sampling times and location (within-row or between-row), SMB in the 0- to 3.8-cm and 3.8- to 7.5-cm soil layers under NT was 87 and 33% greater, respectively, than under CT. Linear regression of soil surface layer (0--3.8 cm) SMB on day-of-year revealed a significant (P {le} 0.10) relationship only within-row and under NT, with a 29% SMB decrease during the growing season. Similar regressions for the other layers and treatments were significant (P > 0.10) or had small seasonal differences. SMB was consistently higher in the between-row locations under both tillage methods. Despite substantial tillage method-induced differences in SMB (50% overall, accompanied by small differential seasonal differences) in the more surficial layers, these alterations appear to have been of little practical consequence, since previous work on these plots revealed essentially no differences in silage utilization of either fertilizer N or soil N relative to tillage method. Thus, the importance of SMB in significantly affecting crop N use in this within-row, banded, maize silage system is questioned.

  8. Tillage system does not affect soil macro fauna in southeastern Buenos Aires province, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Manetti, P. L.; Lopez, A. N.; Clemente, N. L.; Faberi, J.

    2010-07-01

    Soil degradation increased incessantly in the Pampas region of Argentina, due to the intensification of agricultural activities, when carried out with conventional tillage (CT) systems. No-tillage system was adopted as conservation practices by the farmers. The objectives of this study were: a) to determine the macro fauna taxa and their relative abundance under CT and NT in two different seasons; and b) to evaluate soil tillage and seasonal effects on the density of the main macro fauna taxa. The study was conducted from 2002 to 2004 in 46 production farms, in Balcarce, Argentina. Ten soil monoliths (25.2 cm side; 30 cm depth) randomly directed field at July-August; and at October- November to determine the number of individuals of macro fauna and Enchytraeidae. Soil macro fauna density did not differ between tillage systems. Oligochaeta Megadrilli density was generally not affected by the tillage system (P > 0.05) except in 2004 when it was greater under CT in July-August (P = 0.0002). Chilopoda density was greater in soils under NT, with significant differences in 2002 in October-November (P = 0.0070). In July-August of 2003 it was higher in CT (P = 0.0109). Diplopoda were more abundant only under NT in July-August 2004 (P = 0.0010). In July-August a significantly (P < 0.05) higher density of Enchytraeidae was found in CT than NT fields. No differences were observed in the taxonomic composition and the relative abundance of the macro fauna when comparing CT and NT. It can be then concluded that in the study region tillage systems affected slightly soil macro fauna and significantly Enchytraeidae. (Author)

  9. Effects of long-term conservation tillage on soil physical quality of rainfed areas of the Loess Plateau%长期保护性耕作对黄土高原旱地土壤物理质量的影响

    Institute of Scientific and Technical Information of China (English)

    张仁陟; 罗珠珠; 蔡立群; 黄高宝; 李玲玲; 谢军红

    2011-01-01

    Long-term field experiments on soil physical quality in rainfed farming systems were conducted in Dingxi on the western Loess Plateau. The effects of conventional tillage and five conservation agriculture patterns [conventional tillage (T), conventional tillage with stubble incorporation (TS), no till with no stubble (NT), no till with stubble retention (NTS), conventional tillage with plastic mulching (TP) and no till with plastic mulching (NTP)] were studied. The experiment was fully-phased with two rotation sequences. Phase 1 started with field pea (Pisum sativum) followed by spring wheat (Triticum aestivum) (P→W) whereas phase 2 started with spring wheat followed by field pea (W→P). There were highly significant differences between the six tillage measures in soil properties including soil aggregates, available water content, water use efficiency and saturation conductivity. There were also significant differences in some soil properties including soil bulk density, total porosity, capillary porosity, non-capillary porosity, soil strength and saturation capacity. There were no significant differences in soil properties such as soil temperature and field capacity. Using the addition and multiplication method, and weighted integrated method, quantitative assessments of soil physical quality in different tillage systems were carried out. The order of soil physical quality index from high to low was NTS, NTP, NT, TS, T(TP) and TP(T) in P→W rotation, and NTS, NTP, TS, NT, TP and T in W→P rotation. The various tillage measures resulted in very different soil physical quality levels. Improved soil structure arose from tillage reduction or residue retention which improved soil structure, enhanced water infiltration, reduced soil and water loss, and hence improved soil physical quality.%本研究通过设置在陇中黄土高原半干旱区的小麦→豌豆和豌豆→小麦轮作系统的长期定位试验,探讨了不同耕作方式对耕

  10. Zero tillage: A potential technology to improve cotton yield

    Directory of Open Access Journals (Sweden)

    Abbas Hafiz Ghazanfar

    2016-01-01

    Full Text Available Zero tillage technology revealed with no use of any soil inverting technique to grow crops. The crop plant seed is planted in the soil directly after irrigation to make the soil soft without any replenishing in soil layers. A study was conducted to evaluate cotton genotypes FH-114 and FH-142 for the consecutive three years of growing seasons from 2013-15. The seed of both genotypes was sown with two date of sowing, 1 March and 1 May of each three years of sowing under three tillage treatments (zero tillage, minimum tillage and conventional tillage in triplicate completely randomized split-split plot design. It was found from results that significant differences were recorded for tillage treatments, date of sowing, genotypes and their interactions. Multivariate analysis was performed to evaluate the yield and it attributed traits for potential of FH-114 and FH-142 cotton genotypes. The genotype FH-142 was found with higher and batter performance as compared to FH-114 under zero tillage, minimum tillage and conventional tillage techniques. The traits bolls per plant, boll weight, fibre fineness, fibre strength, plant height, cotton yield per plant and sympodial branches per plant were found as most contributing traits towards cotton yield and production. It was also found that FH-142 gives higher output in terms of economic gain under zero tillage with 54% increase as compared to conventional tillage technique. It was suggested that zero tillage technology should be adopted to improve cotton yield and quality. It was also recommended that further study to evaluate zero tillage as potential technology should be performed with different regions, climate and timing throughout the world.

  11. The influence of tillage on field scale water fluxes and maize yields in semi-arid environments: A case study of Potshini catchment, South Africa

    Science.gov (United States)

    Kosgei, J. R.; Jewitt, G. P. W.; Kongo, V. M.; Lorentz, S. A.

    Water is a limiting resource to crop production in arid and semi-arid lands (ASALs) and is responsible for substantial yield losses annually. These lands are often occupied by resource poor smallholder rainfed farmers who have little capacity to establish conventional irrigation infrastructure to mitigate recurrent droughts and dry spells. In situ water harvesting techniques in the form of conservation agriculture practices have been identified and promoted as measures that can improve soil water availability and thus enhance crop yields. Land use practices e.g. tillage influences mechanisms of lateral flow, infiltration, storage, redistribution and residence times of water at field scale. Such alterations in flow paths have not been adequately studied in ASALs where small perturbations at field scale upstream of a catchment may have significant effects downstream. Quantifying these fluxes enables better understanding of productive and non-productive water transition processes and thus to evaluate cropping and management systems. On this study the effects of tillage on water fluxes, soil physical properties and maize ( Zea mays L.) yields were examined at three sites in the Potshini catchment, South Africa. Measurements were made on plots under no-till ( NT) and conventional till ( CT) practices. Seasonal analysis indicated that nearly twice as much runoff was generated from CT treatments when compared to NT plots. However, this was not the case at the beginning of the season. The moisture content in the root zone was significantly higher in NT treatments. Maize yield was also higher in NT compared to CT plots.

  12. 耕作方式对紫色水稻土总有机碳及颗粒态有机碳的影响%Effects of Tillage Systems on Total Organic Carbon and Particulate Organic Carbon in a Purple Paddy Soil

    Institute of Scientific and Technical Information of China (English)

    陈璐豪; 江长胜; 吴艳; 袁雪

    2011-01-01

    To research the influence of different tillage systems on total organic carbon(TOC) and particulate organic carbon(POC) in a purple paddy soil from southwest China,in this paper we put the long-term no-tillage plots,which established since 1989 in the Key Field Station for Monitoring of Eco-environment of Purple Soil of the Ministry of Agriculture of China located in the farm of Southwest University(30°26′N,106°26′E) in Chongqing,as research object to discuss the distribution characteristic of TOC,mass fraction of particulate soil,the concentration of POC and POC distribution ratio in the soil under five tillage treatments including conventional tillage with rice only system(DP),conventional tillage with rotation of rice and rape system(SH),no-till and ridge culture with rotation of rice and rape system(LM),no-till and plain culture with rotation of rice and rape system(XM) and tillage and ridge culture with rotation of rice and rape system(LF).The results showed that different tillage systems had a significant impact on TOC and POC in the surface soil,and LM had the largest contribution to the accumulation of TOC and POC.The TOC ranged from 7.10 g/kg to 34.45 g/kg,the mass fraction of particulate soil ranged from 30.38% to 45.65%,the POC ranged from 1.31 g/kg to 19.39 g/kg under the 0-60 cm soil layer,the basic change trends of all the values were increased with the soil depth decreases.TOC and POC both could be acted as an effective evaluation index in reflecting the effect of tillage systems on the soil quality changes in purple paddy field and soil carbon sequestration capacity,but POC had the greater amplitude in the same tillage systems and a more sensitive response.From the point of view of the relationship between TOC and POC,the increase of organic carbon under different tillage systems had a relationship with the increase of ability to soil physical protection.No-tillage systems were the more helpful tillage in the

  13. Reduced tillage and cover crops as a strategy for mitigating atmospheric CO2 increase through soil organic carbon sequestration in dry Mediterranean agroecosystems.

    Science.gov (United States)

    Almagro, María; Garcia-Franco, Noelia; de Vente, Joris; Boix-Fayos, Carolina; Díaz-Pereira, Elvira; Martínez-Mena, María

    2016-04-01

    The implementation of sustainable land management (SLM) practices in semiarid Mediterranean agroecosystems can be beneficial to maintain or enhance levels of soil organic carbon and mitigate current atmospheric CO2 increase. In this study, we assess the effects of different tillage treatments (conventional tillage (CT), reduced tillage (RT), reduced tillage combined with green manure (RTG), and no tillage (NT)) on soil CO2 efflux, aggregation and organic carbon stabilization in two semiarid organic rainfed almond (Prunus dulcis Mill., var. Ferragnes) orchards located in SE Spain Soil CO2 efflux, temperature and moisture were measured monthly between May 2012 and December 2014 (site 1), and between February 2013 and December 2014 (site 2). In site 1, soil CO2 efflux rates were also measured immediately following winter and spring tillage operations. Aboveground biomass inputs were estimated at the end of the growing season in each tillage treatment. Soil samples (0-15 cm) were collected in the rows between the trees (n=4) in October 2012. Four aggregate size classes were distinguished by sieving (large and small macroaggregates, free microaggregates, and free silt plus clay fraction), and the microaggregates occluded within macroaggregates (SMm) were isolated. Soil CO2efflux rates in all tillage treatments varied significantly during the year, following changes during the autumn, winter and early spring, or changes in soil moisture during late spring and summer. Repeated measures analyses of variance revealed that there were no significant differences in soil CO2 efflux between tillage treatments throughout the study period at both sites. Average annual values of C lost by soil respiration were slightly but not significantly higher under RT and RTG treatments (492 g C-CO2 m-2 yr-1) than under NT treatment (405 g C-CO2 m-2 yr-1) in site 1, while slightly but not significantly lower values were observed under RT and RTG treatments (468 and 439 g C-CO2 m-2 yr-1

  14. Drainage and tillage practices in the winter fallow season mitigate CH4 and N2O emissions from a double-rice field in China

    Science.gov (United States)

    Zhang, Guangbin; Yu, Haiyang; Fan, Xianfang; Yang, Yuting; Ma, Jing; Xu, Hua

    2016-09-01

    Traditional land management (no tillage, no drainage, NTND) during the winter fallow season results in substantial CH4 and N2O emissions from double-rice fields in China. A field experiment was conducted to investigate the effects of drainage and tillage during the winter fallow season on CH4 and N2O emissions and to develop mitigation options. The experiment had four treatments: NTND, NTD (drainage but no tillage), TND (tillage but no drainage), and TD (both drainage and tillage). The study was conducted from 2010 to 2014 in a Chinese double-rice field. During winter, total precipitation and mean daily temperature significantly affected CH4 emission. Compared to NTND, drainage and tillage decreased annual CH4 emissions in early- and late-rice seasons by 54 and 33 kg CH4 ha-1 yr-1, respectively. Drainage and tillage increased N2O emissions in the winter fallow season but reduced it in early- and late-rice seasons, resulting in no annual change in N2O emission. Global warming potentials of CH4 and N2O emissions were decreased by 1.49 and 0.92 t CO2 eq. ha-1 yr-1, respectively, and were reduced more by combining drainage with tillage, providing a mitigation potential of 1.96 t CO2 eq. ha-1 yr-1. A low total C content and high C / N ratio in rice residues showed that tillage in the winter fallow season reduced CH4 and N2O emissions in both early- and late-rice seasons. Drainage and tillage significantly decreased the abundance of methanogens in paddy soil, and this may explain the decrease of CH4 emissions. Greenhouse gas intensity was significantly decreased by drainage and tillage separately, and the reduction was greater by combining drainage with tillage, resulting in a reduction of 0.17 t CO2 eq. t-1. The results indicate that drainage combined with tillage during the winter fallow season is an effective strategy for mitigating greenhouse gas releases from double-rice fields.

  15. Quantifying the Effect of Metformin Treatment and Dose on Glycemic Control

    OpenAIRE

    Jennifer A Hirst; Farmer, Andrew J.; Ali, Raghib; Roberts, Nia W.; Stevens, Richard J

    2012-01-01

    OBJECTIVE Metformin is the first-line oral medication recommended for glycemic control in patients with type 2 diabetes. We reviewed the literature to quantify the effect of metformin treatment on glycated hemoglobin (HbA1c) levels in all types of diabetes and examine the impact of differing doses on glycemic control. RESEARCH DESIGN AND METHODS MEDLINE, EMBASE, and the Cochrane Library were searched from 1950 to June 2010 for trials of at least 12 weeks’ duration in which diabetic patients w...

  16. Enhanced computational