The Experts below are selected from a list of 9675 Experts worldwide ranked by ideXlab platform

Rattan Lal - One of the best experts on this subject based on the ideXlab platform.

  • Tillage and fertilizer effects on root growth of wheat and cotton on a sandy clay loam in pakistan
    Journal of Sustainable Agriculture, 2003
    Co-Authors: M Ishaq, Mohd Zamri Ibrahim, Rattan Lal
    Abstract:

    ABSTRACT Tillage Methods and fertilizer application affect root development, and the yield and quality of crops. Effects of Tillage and fertilizer rates on root length density (RLD) of wheat (Triticum aestivum L.) and cotton (Gossypium hirsutum L.) and macronutrient content of wheat grain grown on a sandy clay loam (fine-loamy, mixed, hyperthermic Typic Haplargids, USDA; Luvic Yermosol, FAO) were evaluated in the semi-arid region of Pakistan. Effects of three Tillage Methods as main plots and three fertilizer rates as sub-plots were studied in a split plot configuration from 1996 to 1999. Tillage treatments were (1) minimum till (MT), (2) conventional till (CT) and (3) deep till (DT). Three rates of NPK fertilizer (kg ha″1) were 60-20-25 (low), 120-40-50 (medium) and 180-60-75 (high) for wheat; and 85-19-25 (low), 170-38-50 (medium) and 255-57-75 (high) for cotton. Tillage Method had no significant effect on the RLD of either wheat or cotton at 0-0.15 m depth. However, greater RLD was obtained for DT in c...

  • crop residue and Tillage effects on carbon sequestration in a luvisol in central ohio
    Soil & Tillage Research, 1999
    Co-Authors: Sjoerd W Duiker, Rattan Lal
    Abstract:

    Abstract Soils play a key role in the global carbon cycle. They can be a source or a sink of carbon and influence CO 2 concentrations in the atmosphere. In order to calculate the carbon budget of a region, the effect of soil management practices on carbon sequestration in soils needs to be quantified. Objectives of this experiment were to determine: (i) the effects of ridge till, plow till and no-till on the soil organic carbon (SOC) pool; (ii) the SOC loss or sequestration for mulch rates of 0–16 Mg ha −1  year −1 wheat ( Triticum aestivum L.) straw applied in combination with each Tillage Method, and (iii) impacts of Tillage and crop residue treatments on soil physical quality, including aggregation and porosity. The experiment was initiated in 1989 on a Crosby silt loam (Stagnic Luvisol) in Central Ohio. Seven years after initiation of the experiment, there was a positive, linear effect of residue application rate on SOC contents in all Tillage treatments. In the eighth year of the experiment these trends were confirmed for plow and no-till, but not for ridge till. Linear-regression equations, relating SOC content for the 0–10 cm soil depth to mulch rate, were: for no-till: SOC (Mg ha −1 ) = 15.21 + 0.32 [Residue (Mg ha −1  year −1 )] ( r  = 0.68) and for plow till: SOC = 11.95 + 0.27 [Residue] ( p  = 0.72). The carbon conversion efficiencies were 8% per year for plow till and 10% per year for no-till. Detailed sampling at different depths revealed that increases in SOC content were only significant for the 0–5 cm depths of plow and no-till treatments. Effects of crop residue application on water stable aggregation in the 0–10 cm layer were most pronounced with plow till and ridge till but not with no-till. Water retention characteristics, a measure of pore size distribution, was not influenced by Tillage system, but crop residue application had a significant effect on water retention in the 0–10 cm layer at matric suctions of 30–300 kPa. This means that residue application increased macropores of diameters 1–10 μm. It is concluded that, depending on the amount of crop residue returned to the soil, the large numbers of farmers converting from plow to no-till cultivation in the Corn Belt may create an important sink for atmospheric CO 2 .

  • soil degradative effects of slope length and Tillage Methods on alfisols in western nigeria i runoff erosion and crop response
    Land Degradation & Development, 1997
    Co-Authors: Rattan Lal
    Abstract:

    Field runoff plots were established in 1984 to evaluate the effects of slope length on runoff, soil erosion and crop yields on newly cleared land for four consecutive years (1984–1987) on an Alfisol at Ibadan, Nigeria. The experimental treatments involved six slope lengths (60 m to 10 m at 10-m increments) and two Tillage Methods (plough-based conventional Tillage and a herbicide-based no-till Method) of seedbed preparation. A uniform crop rotation of maize (Zea mays)/cowpeas (Vigna unguiculata) was adopted for all four years. An uncropped and ploughed plot of 25 m length was used as a control. The water runoff from the conventional Tillage treatment was not significantly affected by slope length, but runoff from the no-till treatment significantly increased with a decrease in slope length. The average runoff from the no-till treatment was 1·85 per cent of rainfall for 60 m, 2·25 per cent for 40 m, 2·95 per cent for 30 m, 4·7 per cent for 20 m and 5·15 per cent for 10 m slope length. In contrast to runoff, soil erosion in the conventional Tillage treatment decreased significantly with a decrease in slope length. For conventional Tillage, the average soil erosion was 9·59 Mg ha−1 for 60 m, 9·88 Mg ha−1 for 50 m, 6·84 Mg ha−1 for 40 m, 5·69 Mg ha−1 for 30 m, 1·27 Mg ha−1 for 20 m and 2·19 Mg ha−1 for 10 m slope length. Because the no-till Method was extremely effective in reducing soil erosion, there were no definite trends in erosion with regard to slope length. The average sediment load (erosion:runoff ratio) also decreased with a decrease in slope length from 66·3 kg ha−1 mm−1 for 60 m to 36·3 kg ha−1 mm−1 for 10 m slope length. The mean C factor (ratio of soil erosion from cropped land to uncropped control) also decreased with a decrease in slope length. Similarly, the erosion:crop yield ratio decreased with a decrease in slope length, and the relative decrease was more drastic in conventional Tillage than in the no-till treatment. The slope length (L) and erosion relationship fits a polynomial function (Y=c+aL+bL2). Formulae are proposed for computing the optimum terrace spacing in relation to slope gradient and Tillage Method. © 1997 John Wiley & Sons, Ltd.

  • long term Tillage and maize monoculture effects on a tropical alfisol in western nigeria ii soil chemical properties
    Soil & Tillage Research, 1997
    Co-Authors: Rattan Lal
    Abstract:

    Abstract Intensive monocropping of maize is widely practised in densely populated regions of west Africa. A wide range of Tillage systems are used for seedbed preparation without the benefits of research information from long-term experiments relating Tillage Method to soil properties. Soil chemical effects of eight Tillage and residue management treatments were studied for 8 years or 16 consecutive maize monoculture crops for a western Nigerian soil with a coarse-textured surface horizon. Treatments established on a newly cleared land were: (1) notill ± crop residue mulch, (2) notill ± chiselling in the row zone at 50 cm depth, (3) mouldboard ploughing ± harrowing, (4) disc ploughing ± rotovation, (5) notill − residue mulch, (6) mouldboard ploughing at the end of rains or summer ploughing, (7) mouldboard ploughing ± residue mulch, and (8) mouldboard ploughing and harrowing ± ridging or ridge till. Soil chemical properties of the 0–5-cm and 5–10-cm depths were measured during the dry season every year beginning with base line characterization soon after land clearing in 1980. Soil pH declined with cultivation duration from 6.6 in 1981 to 5.4 in 1987 for the 0–5-cm depth, and from 6.5 in 1981 to 5.5 in 1987 for the 5–10-cm depth. Mean soil pH for the 0–5-cm depth declined from 6.7 to 5.6 in notill ± residue mulch, and from 6.7 to 5.4 with mouldboard ploughing. Soil content of Bray P increased with cultivation duration due to application of phosphatic fertilizers. There occurred a significant decrease in soil organic carbon (SOC) and total soil nitrogen (TSN), and an increase in C:N ratio with cultivation duration. Mean SOC content in 1987 of the 0–5-cm depth was 13.9 g kg −1 for the notill treatment compared with 11.0 g kg −1 for the plough-based Methods. Soil concentration of Ca and Mg and total cation exchange capacity (CEC) increased with cultivation duration. Maize grain yield was significantly correlated with SOC, exchangeable Ca 2+ , and CEC. Continuous cropping decreased soil chemical quality, and the rate of decreases was more with plough-based than notill Methods.

Jiwang Zhang - One of the best experts on this subject based on the ideXlab platform.

  • integrated agronomic practices management improve yield and nitrogen balance in double cropping of winter wheat summer maize
    Field Crops Research, 2018
    Co-Authors: Shuting Dong, Bin Zhao, Jiwang Zhang
    Abstract:

    Abstract Crop production alters nitrogen balance in double cropping of winter wheat-summer maize in grain nitrogen content, soil nitrogen pool and nitrogen loss, ultimately affecting nitrogen use efficiency and environmental health. In comparison to the information on crop responses only limited knowledge exists on the response of nitrogen balance to integrated agronomic practices management (IAPM, defined as a comprehensive management framework consisted of Tillage Method, plant density, seeding and harvest dates, and fertilizer application) under field. Planting pattern will affect crop production and environmental costs. And how the nitrogen balance change under IAPM? In order to answer this question, four treatments (T1, T2, T3 and T4) were conducted on double cropping of winter wheat-summer maize for 4 years in North China Plain. Annual grain yield of T2, T3, and T4 was 22.0%, 51.2%, and 33.3%, respectively, higher than T1. And single grain yield of winter wheat or summer maize had the same trend as the annual grain yield. Dry matter accumulation of T2, T3, and T4 in summer maize season were 8.3%, 42.0%, and 23.0%, and those in winter wheat season were 3.9%, 25.7%, and 12.1%, respectively, higher than T1 at harvest. The grain yield of T4 was lower than that of T3 but higher than that of T1 and T2, and net profit and nitrogen use efficiency of T4 were higher than that of T3. Meanwhile the highest current and residual nitrogen recovery efficiency (CREN and REREN) were obtained by T4 treatment during the study period. The soil nitrogen content in 0–90 depth (SN), grain nitrogen content (GN), nitrogen apparent recovery efficiency (AREN) and fertilizer nitrogen loss (FNL) were measured for nitrogen balance. T4 treatment promoted nitrogen balance as higher GN, higher AREN and lower FNL. The GN kept stable and FNL was increasing slowly in all treatments, which mean the contribution to soil nitrogen pool was decreasing with experimental years. The grain yield for T4 treatment of winter wheat, summer maize and annual increased by 36.4%, 31.3% and 33.3% averagely in the past 4 years, compared with T1 treatment. While maintaining crop production, T4 treatment made an important contribution to promoting nitrogen use efficiency, improving the situation of nitrogen balance, and reducing nitrogen loss about 39.1–54.4%, compared with other treatments.

  • effects of integrated agronomic practices management on root growth and development of summer maize
    European Journal of Agronomy, 2017
    Co-Authors: Shuting Dong, Bin Zhao, Jiwang Zhang
    Abstract:

    Abstract Root growth and development of summer maize ( Zea mays L.) is an important process in determining grain yield. In comparison to the information on above ground plant responses only limited knowledge exists on the response of root growth and development to integrated agronomic practices management (defined as a comprehensive management framework consisted of Tillage Method, plant density, seeding and harvest date, and fertilizer application) under field conditions. Two experiments, integrated agronomic practices management (IAPM) and nitrogen rate testing (NAT) were used to determine the effects on summer maize root system in the course of five years in North China. IAPM consisted of four treatments (CK: local conventional cultivation practices, Opt-1: an optimized combination of cropping system and fertilizer treatment, HY: treatment based on high-yield studies, and Opt-2: a further optimized combination of cropping system and fertilizer treatment). NAT had four treatments of nitrogen rate (0, 129.0, 184.5, and 300.0 kg N ha −1 ).Individual/population root dry weight, individual/population absorption area, surface, volume, and length density of root and grain yield were measured. Roots were sampled per plot at six-leaf stage (V6), tasseling stage (VT), milk stage (R3) and physiological maturity stage (R6). The results from IAPM revealed that Opt-2 significantly increased dry weight, volume, superficial area, and length density of root across the 0–30 cm soil layer of whole growth period. Root active absorption area of Opt-2 exhibited a significant increase in the 0–30 cm soil layer of whole growth period except V6. In compare with root/shoot ratio of CK, this of Opt-2 increased by 14.5% at VT and 16.3% at R6. Results from NAT revealed that N with a range from 0 to 184.5 kg N ha −1 played a positive role in root growth and development. Dry weight, absorbing area of root, and the root/shoot ratio increased as N rate rise within certain limits and then decreased significantly. Dry weight, the proportion of deeply distributed, absorption area, length density of root, and root/shoot ratio increased due to appropriate population, reasonable fertilizer management, and suitable harvest date, which provided sufficient nutrients and moisture to aboveground parts for growth, development, and high grain yield of summer maize.

Miguel Angel Cantamutto - One of the best experts on this subject based on the ideXlab platform.

  • self regeneration of hairy vetch vicia villosa roth as affected by seedling density and soil Tillage Method in a semi arid agroecosystem
    Grass and Forage Science, 2017
    Co-Authors: Juan P Renzi, Guillermo R Chantre, Miguel Angel Cantamutto
    Abstract:

    Vicia villosa Roth is a forage legume with the capability for biological N fixation and natural reseeding, which could contribute to sustainability in semi-arid regions. This study aimed to determine (i) the relationship between vetch density, seed production and spontaneous seed dispersal; (ii) the impact of the post-dispersal Tillage treatment over the soil seedbank dynamics; and (iii) potential predation of the seedbank by feral pigeons. A density range between 50 and 200 plants m−2 did not influence seed production or seed dispersal. Shallow disc Tillage (SDT) clearly favoured self-regeneration, resulting in higher amount of emerged seedlings during autumn compared to no Tillage (NT). Based on observed emergence data, the percentage of emerged seedlings under SDT and NT were 38 and 6% of the seedbank, respectively, during 18 months after plot harvest. The lowest emergence values registered under NT could be associated with higher pressure from natural predators, soil-borne pathogens, seed decay by ageing and false breaks. The feral pigeon (Columba livia var.) might be considered the main cause of vetch seedbank depletion in this study. Under controlled conditions, a single pigeon is able to consume, on average, between 184 and 768 seeds per day, depending on seed exposure and alternative food sources availability.

Guillermo R Chantre - One of the best experts on this subject based on the ideXlab platform.

  • self regeneration of hairy vetch vicia villosa roth as affected by seedling density and soil Tillage Method in a semi arid agroecosystem
    Grass and Forage Science, 2017
    Co-Authors: Juan P Renzi, Guillermo R Chantre, Miguel Angel Cantamutto
    Abstract:

    Vicia villosa Roth is a forage legume with the capability for biological N fixation and natural reseeding, which could contribute to sustainability in semi-arid regions. This study aimed to determine (i) the relationship between vetch density, seed production and spontaneous seed dispersal; (ii) the impact of the post-dispersal Tillage treatment over the soil seedbank dynamics; and (iii) potential predation of the seedbank by feral pigeons. A density range between 50 and 200 plants m−2 did not influence seed production or seed dispersal. Shallow disc Tillage (SDT) clearly favoured self-regeneration, resulting in higher amount of emerged seedlings during autumn compared to no Tillage (NT). Based on observed emergence data, the percentage of emerged seedlings under SDT and NT were 38 and 6% of the seedbank, respectively, during 18 months after plot harvest. The lowest emergence values registered under NT could be associated with higher pressure from natural predators, soil-borne pathogens, seed decay by ageing and false breaks. The feral pigeon (Columba livia var.) might be considered the main cause of vetch seedbank depletion in this study. Under controlled conditions, a single pigeon is able to consume, on average, between 184 and 768 seeds per day, depending on seed exposure and alternative food sources availability.

R. P. Zentner - One of the best experts on this subject based on the ideXlab platform.

  • Effects of Tillage Method and crop rotation on non-renewable energy use efficiency for a thin Black Chernozem in the Canadian Prairies.
    Soil & Tillage Research, 2004
    Co-Authors: R. P. Zentner, C.n. Nagy, D. A. Derksen, Guy P. Lafond, D.d. Wall
    Abstract:

    Producers in the Canadian Prairies have begun to extend and diversify their cereal-based rotations by including oilseed and pulse crops, and by managing these newer cropping systems with minimum- and zero-Tillage practices. This study examined the implications of these land use changes on non-renewable energy requirements (both direct and indirect), energy output, and energy use efficiency for monoculture cereal, cereal–oilseed, and cereal–oilseed–pulse rotations, each managed using conventional (CT), minimum (MT), and zero (ZT) Tillage practices on a thin Black Chernozem in Saskatchewan, Canada. The crop rotations included: spring wheat (Triticum aestivum L.)–spring wheat–winter wheat–fallow (Ws–Ws–Ww–F), spring wheat–spring wheat–flax (Linum usitatissimum L.)–winter wheat (Ws–Ws–Fx–Ww), and spring wheat–flax–winter wheat–field pea (Pisum sativum L.) (Ws–Fx–Ww–P). The findings, based on 12 years of data, showed that non-renewable energy use for the complete cropping systems was largely unaffected by Tillage Method, but that it differed significantly with crop rotations. Energy requirements were lowest for Ws–Ws–Ww–F (average 6389 MJ ha−1), intermediate for Ws–Fx–Ww–P (11% more), and highest for the Ws–Ws–Fx–Ww (28% more). The substitution of pea for spring wheat in the Ws–Fx–Ww–P versus Ws–Ws–Fx–Ww rotation reduced total energy use by 13%, reflecting the minimal requirement for N fertilizer by pulses due to their ability to biologically fix N, and from the lower fertilizer N rate that was applied to spring wheat grown after the legume. The use of MT and ZT practices provided significant energy savings (compared to CT) in on-farm use of fuel and in machine operation and manufacture for some cropping system components (e.g., summerfallow preparation, spring wheat grown on pea stubble, and for pea grown on cereal stubble), but these savings were often offset by higher energy requirements for herbicides and for N fertilizer with conservation Tillage management. Gross energy output averaged 32 315 MJ ha−1 for Ws–Ws–Ww–F, 41 287 MJ ha−1 (or 28% more) for Ws–Ws–Fx–Ww, and 42 961 (or 33% more) for Ws–Fx–Ww–P. Tillage Method had little overall influence on energy output for the monoculture cereal and cereal–oilseed–pulse rotations, but it was generally lower with CT than with MT or ZT management for the cereal–oilseed rotation. Energy use efficiency, measured as grain produced per unit of energy input and as the ratio of energy output to energy input, was highest for the cereal–oilseed–pulse rotation (373 and 6.1 kg GJ−1, respectively) and lower, but generally similar, for the cereal–oilseed and monoculture cereal rotations (298 and 5.1 kg GJ−1, respectively). The use of conservation Tillage management enhanced overall energy use efficiency for the two mixed rotations, but not for the monoculture cereal rotation. We concluded that adopting diversified crop rotations, together with minimum and zero Tillage management practices, will enhance non-renewable energy use efficiency of annual grain production in this sub-humid region.

  • Tillage Method and crop diversification effect on economic returns and riskiness of cropping systems in a thin black chernozem of the canadian prairies
    Soil & Tillage Research, 2002
    Co-Authors: R. P. Zentner, D. A. Derksen, Guy P. Lafond, C A Campbell
    Abstract:

    Abstract Producers throughout the Canadian Prairies have begun to extend (reducing summerfallow frequency) and diversify their traditional cereal-based rotations by devoting more areas to oilseeds and pulses, and by managing these newer cropping systems with conservation Tillage practices. This study examined the economic performance and relative riskiness of monoculture cereal, cereal–oilseed, and cereal–oilseed–pulse rotations, each managed under conventional-, minimum-, and zero-Tillage practices over a 12-year period (1987–1998) in the sub-humid Black soil zone of Saskatchewan. These crop rotations included: spring wheat (Triticum aestivum L.)–spring wheat–winter wheat (T. aestivum L.)–fallow (Ws–Ws–Ww–F), spring wheat–spring wheat–flax (Linum usitatissimum L.)–winter wheat (Ws–Ws–Fx–Ww), and spring wheat–flax–winter wheat–field pea (Pisum sativum L.) (Ws–Fx–Ww–P). Annual production costs for the complete rotation systems increased with cropping intensity and cropping diversity (monoculture cereal ($ 249 ha−1)