• Authors:
    • Poswal, R. S.
    • Yadav, A.
    • Gupta, R. K.
    • Gill, S. C.
    • Chhokar, R. S.
    • Kumar, V.
    • Sharma, R. K.
    • Kumar, A.
    • Mehta, A.
    • Kleemann, S. G. L.
    • Cummins, J. A.
    • Coventry, D. R.
  • Source: Field Crops Research
  • Volume: 123
  • Issue: 3
  • Year: 2011
  • Summary: This article reports on field experiments with 4 different rotations that are commonly used throughout Haryana in NW India (rice-wheat, cotton-wheat, pearl millet-wheat, cluster bean-wheat), where we assess wheat yield and chapatti quality measures with different crop establishment methods and input of micronutrients. In a series of experiments conducted on farmers' fields in 2007-2008 and 2008-2009 winter seasons, the addition of micronutrients and sulphur to wheat crops was used alongside the use of a common farmer practice, the use of farmyard manure (FM) and best practice inputs of N-fertilizer (150 kg N ha -1), P-fertilizer (26 kg P ha -1) and K-fertilizer (33 kg K ha -1). The application of FM with the recommended NPK treatment produced 9-13% more grain yield in the rice-wheat rotation when compared with the recommended NPK only treatment. Given that the farm sites used here had low levels of soil P, this may suggest that the recommended rate of 26 kg P ha -1 for the rice-wheat rotation is too low. The addition of FM did not improve any grain quality outcomes at any of the sites. There were no yield responses with S application with any of the rotations but the S input resulted in more wheat protein from all sites (average 8%). The addition of S also gave similar increases in grain hardness and the chapatti score. The inclusion of micronutrients (boron, copper, iron, zinc and manganese) with the recommended NPK treatment did not increase the grain yield at any of the sites when compared with the recommended NPK treatment, and sometimes, but not consistently, gave small responses with protein, grain hardness and chapatti score. In concurrent experiments wheat growth and chapatti quality were compared in zero till and conventionally sown systems, and with and without S fertilizer amendment. Here too there were no grain yield responses to S, and the protein, grain hardness and chapatti score were increased with S addition. Grain yields with zero till and conventional wheat were similar in the rice-wheat system and zero till sowing resulted in small increases in yield at all of the non-rice sites. The grain from the zero till treatments had higher protein (1-3%), grain hardness (3-10%) and chapatti score from all 4 rotations. Zero till has substantial adoption in the rice-wheat districts of Haryana but little farmer awareness and adoption in the areas where the other rotations are used. The data given here show that with zero tillage and an integrated practice of nutrient management farmers in Haryana can maintain grain yields of wheat whilst improving quality outcomes.
  • Authors:
    • Crusciol, C. A. C.
    • Garcia, . A.
    • Castro, G. S. A.
    • Rosolem, C. A.
  • Source: Revista Brasileira de Ciência do Solo
  • Volume: 35
  • Issue: 6
  • Year: 2011
  • Summary: Especially under no-tillage, subsuface soil acidity has been a problem, because it depends on base leaching, which has been associated with the presence of low molecular weigth organic acids and companion anions. The objective of this study was to evaluate exchangeable base cation leaching as affected by surface liming along with annual urea side-dressing of maize and upland rice. Treatments consisted of four lime rates (0, 1500, 3000, and 6000 kg ha -1) combined with four nitrogen rates (0, 50, 100, and 150 kg ha -1) applied to maize ( Zea mays) and upland rice ( Oryza sativa), in two consecutive years. Maize was planted in December, three months after liming. In September of the following year, pearl millet ( Pennisetum glaucum) was planted without fertilization and desiccated 86 days after plant emergence. Afterwards, upland rice was grown. Immediately after upland rice harvest, 18 months after surface liming, pH and N-NO 3-, N-NH 4+, K, Ca, and Mg levels were evaluated in soil samples taken from the layers 0-5, 5-10, 10-20 and 20-40 cm. Higher maize yields were obtained at higher N rates and 3000 kg ha -1lime. Better results for upland rice and pearl millet yields were also obtained with this lime rate, irrespective of N levels. The vertical mobility of K, Ca and Mg was higher in the soil profiles with N fertilization. Surface liming increased pH in the upper soil layers causing intense nitrate production, which was leached along with the base cations.
  • Authors:
    • Bustamante, M. M. da C.
    • Cruvinel, E. B. F.
    • Kozovits, A. R.
    • Zepp, R. G.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 144
  • Issue: 1
  • Year: 2011
  • Summary: In the last 40 years, a large area of savanna vegetation in Central Brazil (Cerrado) has been converted to agriculture, with intensive use of fertilizers, irrigation and management practices. Currently, the Cerrado is the main region for beef and grain production in Brazil. However, the consequences of these agricultural practices on NO, N 2O and CO 2 emissions from soil to atmosphere are still poorly investigated. The objectives of this study were to quantify soil emissions of NO-N, N 2O-N and CO 2-C in different no-till cultivation systems in comparison with native savanna vegetation. The agricultural areas included: (a) the maize and Brachiaria ruzizienses intercropping system followed by irrigated bean in rotation; (b) soybean followed by natural fallow; and (c) cotton planting over B. ruzizienses straw. The study was performed from August 2003 to October 2005 and fluxes were measured before and after planting, after fertilizations, during the growing season, before and after harvesting. NO-N fluxes in the soybean field were similar to those measured in the native vegetation. In the cornfield, higher NO-N fluxes were measured before planting than after planting and pulses were observed after broadcast fertilizations. During Brachiaria cultivation NO-N fluxes were lower than in native vegetation. In the irrigated area (bean cultivation), NO-N fluxes were also significantly higher after broadcast fertilizations. Most of the soil N 2O-N fluxes measured under cultivated and native vegetation were very low (<0.6 ng N 2O-N cm -2 h -1) except during bean cultivation when N 2O-N fluxes increased after the first and second broadcast fertilization with irrigation and during nodule senescence in the soybean field. Soil respiration values from the soybean field were similar to those in native vegetation. The CO 2-C fluxes during cultivation of maize and irrigated bean were twice as high as in the native vegetation. During bean cultivation with irrigation, an increase in CO 2-C fluxes was observed after broadcast fertilization followed by a decrease after the harvest. Significantly lower soil C stocks (0-30 cm depth) were determined under no-tillage agricultural systems in comparison with the stocks under savanna vegetation. Fertilizer-induced emission factors of N oxides calculated from the data were lower than those indicated by the IPCC as default.
  • Authors:
    • da Silva, D. A.
    • Ferreira de Souza, L. C.
    • Tadeu Vitorino, A. C.
    • Goncalves, M. C.
  • Source: Bragantia
  • Volume: 70
  • Issue: 1
  • Year: 2011
  • Summary: Soil physical degradation, like compaction, reduces water movement and root development. Soil structure is considered one of most importance to agriculture and closely related to it are other fundamental properties in soil-plant relationship. The objective of this study was to evaluate the effect of crop sequences on physical attributes. The research was realized in 2004/05 and 2005/06 growing seasons, in a Typic Clayey Rhodic Hopludox, under eight years of no-tillage system, at Dourados (MS). The experiment was a randomized complete block design, with three replications. Treatments were constituted by cover crops: sunflower (Helianthus annuus L.), sunnhemp (Crotalaria juncea L.), hairy vetch (Vicia villosa Roth), mixture of sunnhemp + black oat (Avena strigosa Schreb), and mixture of black oat + hairy vetch + oilseed radish (Raphanus sativus L. Var. oliferus Metzg). Differences were not observed in soil density, porosity and aggregation rate when it was cultivated with sunflower, hairy vetch, sunnhemp, or the mixtures. Differences were observed in soil physical properties between 0-5 cm layer and 5-10cm 10-20 cm layers, but no differences between 5-10 cm and 10-20cm layers. Soil carbon trend to higher contents in crops with high production of surface residues, although differences in carbon contents were insufficient to modify aggregation.
  • Authors:
    • Kuai, D.
    • DianXiong, C.
    • XiaoMing, Z.
    • Yan, W.
    • QuanSheng, Z.
    • DingChen, Z.
    • ZongHui, F.
    • XiaoHong, X.
    • XiaoBin, W.
  • Source: Transactions of the Chinese Society of Agricultural Engineering
  • Volume: 27
  • Issue: 2
  • Year: 2011
  • Summary: A six-year experiment (2003 to 2008) was conducted in Shouyang Dryland Farming Experimental Station in Shanxi Province to study the effect of different tillage practices (no-tillage, reduced tillage and conventional tillage) with three nitrogen (N) and phosphorus (P 2O 5) fertilizer rates (105, 179 and 210 kg/hm2; N:P 2O 5=1:1) on spring corn yield and water use efficiency. The results showed that at the recommended fertilizer rate of 105 kg/hm 2, the average yield and water use efficiency (WUE) were about 5 234 kg/hm 2 and 12.4 kg/(hm 2.mm), respectively, under conventional tillage (CT), and about 5 751 kg/hm 2 and 13.6 kg/(hm 2.mm), respectively, under reduced tillage (RT). The average yield and WUE under RT increased by about 9.9% and 9.7%, respectively, compared to CT. Under no-tillage (NT), the average yield and WUE, at the fertilizer rate of 179 kg/hm 2, were highest, about 5 336 kg/hm 2 and 13.2 kg/(hm 2.mm), respectively, which were about 6.1% and 9.7% higher than those under CT. The NT increased soil water contents, resulting in higher yields in dry years, compared to CT. Among three tillage practices, the average yield and WUE were ranked as RT >NT >CT.
  • Authors:
    • Dalal, R. C.
    • Allen, D. E.
    • Wang, W. J.
    • Reeves, S.
    • Gibson, I.
  • Source: Soil & Tillage Research
  • Volume: 112
  • Issue: 2
  • Year: 2011
  • Summary: Conservation agricultural practices such as no-till (NT) and crop residue retention (CRR), and nutrient application, increases soil organic C (SOC) and are considered effective measures of C sequestration in soil. However, long-term effects of individual components of conservation agriculture and their interactions on SOC are rarely evaluated; as a result, conflicting findings of these practices on SOC are reported in the literature. We measured SOC and soil total N in a balanced factorial experiment, conducted on a Vertisol, consisting of tillage practices (conventional mechanical tillage, CT; and no-tillage, NT), crop residue management (crop residue burned, CRB; and crop residue retained, CRR) and N fertiliser application (no N, 30 kg N ha -1 year -1; and 90 kg N ha -1 year -1). The site, in a semiarid subtropical region, was cropped with wheat ( Triticum aestivum L.) except for 3 years of barley ( Hordeum vulgare L.), for 40 years using conservation practices. In general, tillage effects on SOC and soil total N were small. Crop residue and N fertiliser interactively increased SOC and total N stocks at 0-0.1 m depth and cumulative stocks at 0-0.2 m and 0-0.3 m depths; that is, CRR increased SOC and soil total N only when N fertiliser was applied, and fertilisation increased SOC and soil total N only under CRR treatment. Depletion of delta 13C values in CRR treatments and delta 15N values in N treatments strongly indicated the contribution of crop residue (and root biomass) and N fertiliser to soil organic matter in this Vertisol. From this study and previous findings from this site, it appears, however, the effects of crop residue retention and N fertiliser occurred in early years, and did not continually increase SOC and total soil N with increasing period of conservation practices.
  • Authors:
    • de Campos, B. -H. C.
    • Carneiro Amado, T. J.
    • Bayer, C.
    • da Silveira Nicoloso, R.
    • Fiorin, J. E.
  • Source: Revista Brasileira de Ciência do Solo
  • Volume: 35
  • Issue: 3
  • Year: 2011
  • Summary: Soil organic matter (SOM) plays a crucial role in soil quality and can act as an atmospheric C-CO2 sink under conservationist management systems. This study aimed to evaluate the long-term effects (19 years) of tillage (CT-conventional tillage and NT-no tillage) and crop rotations (R0-monoculture system, R1-winter crop rotation, and R2- intensive crop rotation) on total, particulate and mineral-associated organic carbon (C) stocks of an originally degraded Red Oxisol in Cruz Alta, RS, Southern Brazil. The climate is humid subtropical Cfa 2a (Koppen classification), the mean annual precipitation 1,774 mm and mean annual temperature 19.2 degrees C. The plots were divided into four segments, of which each was sampled in the layers 0-0.05, 0.05-0.10, 0.10-0.20, and 0.20-0.30 m. Sampling was performed manually by opening small trenches. The SOM pools were determined by physical fractionation. Soil C stocks had a linear relationship with annual crop C inputs, regardless of the tillage systems. Thus, soil disturbance had a minor effect on SOM turnover. In the 0-0.30 m layer, soil C sequestration ranged from 0 to 0.51 Mg ha(-1) yr(-1), using the CT R0 treatment as base-line; crop rotation systems had more influence on soil stock C than tillage systems. The mean C sequestration rate of the cropping systems was 0.13 Mg ha(-1) y(-1) higher in NT than CT. This result was associated to the higher C input by crops due to the improvement in soil quality under long-term no-tillage. The particulate C fraction was a sensitive indicator of soil management quality, while mineral-associated organic C was the main pool of atmospheric C fixed in this clayey Oxisol. The C retention in this stable SOM fraction accounts for 81 and 89% of total C sequestration in the treatments NT R1 and NT R2, respectively, in relation to the same cropping systems under CT. The highest C management index was observed in NT R2, confirming the capacity of this soil management practice to improve the soil C stock qualitatively in relation to CT R0. The results highlighted the diversification of crop rotation with cover crops as a crucial strategy for atmospheric C-CO2 sequestration and SOM quality improvement in highly weathered subtropical Oxisols.
  • Authors:
    • Rosolem, C. A.
    • de Fatima Esteves, J. A.
  • Source: Revista Brasileira de Ciencia do Solo
  • Volume: 35
  • Issue: 3
  • Year: 2011
  • Summary: Water soluble phosphates are the most often used phosphorus sources in fertilizers for ease of P release to the soil. However, in tropical soils, much of this P is adsorbed to soil particles and becomes unavailable to plants. Conversely, reactive phosphates may be slow initial releasers of the nutrient, but be released continually to the developing crops, reducing soil P fixation. The aim of this study was to investigate the application of two P sources to triticale and assess the residual effect of fertilization on pearl millet in no tillage. Soil fertility, dry matter and grain yields, phosphorus content and amount in plants and straw were determined. The experiment was conducted in an Oxisol. Three treatments were applied in April of the first year: (1) without application of P 2O 5, (2) application of 80 kg ha -1 P 2O 5 as triple superphosphate and (3) application of 80 kg ha -1 P 2 O 5 of reactive phosphate (Arad). Triticale (* Triticosecale Wittmack) was planted and grown until grain harvest. In September, after harvest of triticale, pearl millet ( Pennisetum glaucum (L.) R. Brown) was planted to increase the amount of straw on the soil surface. At flowering in November, pearl millet was desiccated. Soluble phosphate, which was applied to the soil surface, increased soil P contents down to the 5-10 cm soil layer, and triticale benefited from P fertilization with higher yields. Despite the increase in available phosphorus in the soil provided by soluble phosphate, P application to triticale did not increase dry matter production, P content and amount in the shoots of the pearl millet grown in sequence.
  • Authors:
    • Devine, S.
    • Markewitz, D.
    • Hendrix, P.
    • Coleman, D.
  • Source: Forest Science
  • Volume: 57
  • Issue: 1
  • Year: 2011
  • Summary: Forest succession (FS) and no-till (NT) agriculture are generally assumed to have a beneficial effect on surficial soil organic C (SOC) stocks compared with conventional tillage (CT) management; however, land use effects to depths >30 cm remain uncertain. In this research we compared SOC contents and composition to 2 m under CT, NT, and FS at the 30-year Horseshoe Bend agroecosystem experiment in Athens, Georgia, USA. Soils from 0 to 2 m were fractionated into particulate organic C (POC) (53-2000 m) and fine C (<53 m) fractions, and bulk soil delta 13C signatures were determined. Soils from 0 to 28 cm were dry- and wet-sieved to estimate aggregate stability. Soil solutions were also collected at 0, 15, and 100 cm for dissolved organic C (DOC) analysis. Full-profile (0-2 m) SOC storage is 52 Mg ha -1 in CT, 60 Mg ha -1 in NT, and 62 Mg ha -1 in FS. Significant differences are limited to 0-5 cm and are linked to enhanced aggregate stability under NT and FS. Increases in subsoil POC under FS and changes in soil delta 13C and C/N ratio indicate that substantial subsoil C cycling has occurred. DOC fluxes at 0 cm were significantly greater under NT (200 kg ha -1 year -1) and FS (210 kg ha -1 year -1) than under CT (80 kg ha -1 year -1). DOC fluxes at 15 cm are estimated to be 20 kg ha -1 year -1 under CT and NT and 40 kg ha -1 year -1 under FS. At 100 cm, DOC fluxes are 2 kg ha -1 year -1, regardless of land use. An increase in FS POC of 2 Mg ha -1 from 15 to 100 cm outweighs cumulative differences in DOC input to this layer, implicating deep forest rooting and bioturbation as active mechanisms in subsoil C change. Whereas differences in SOC content were concentrated near the surface, dynamic changes in C cycling extend well below the plow layer.
  • Authors:
    • Dicu, D.
    • Ţărau, D.
    • Borza, I.
  • Source: Research Journal of Agricultural Science
  • Volume: 43
  • Issue: 3
  • Year: 2011
  • Summary: This study presents some aspects regarding the physical-geographical characterization necessary for the experimental field localization. Briefly introduced are the geology and lithology of surface materials, climate conditions, land drainage etc., as defining elements for edaphic resources' main characteristics. To determine the physical, chemical and biological properties of Cambic Chernozems from Aradul Nou (Romania), more samples were collected in both natural settlement and in disturbed settlement. Soil conditions also determined the defining characteristics for the ecosystems productivity, granulated structure and humus content. Maize, soyabean and wheat were used as test plants. The results obtained in the soil and climate conditions mentioned, although not allow for a clear formulation of recommendations in the culture systems tested, but the background information gathered is extremely valuable for scientific substantiation of appropriate technologies in the future for climatic conditions specific of the area in which investigations were undertaken as well as similar areas, conservative tillage systems representing alternatives to conventional tillage systems by the effects of conservation of soil properties and yields In terms of crop suitability to no-till system, soil texture has some restrictions due to clay-clay and secondary compaction, without excluding the possibility of adopting no-till practices. Yields obtained by applying the conservative systems, can achieve differentiated results that show, at least close if not superior to classical ones. Choosing the system should be made, as appropriate, depending on plant, soil and climate specific conditions. The research supports the ability to promote no-till technology in production established itself selective implementation, where conditions are suitable ecopedological this system of agriculture, under effective management.