• Authors:
    • Bates, R. T.
    • Gallagher, R. S.
    • Curran, W. S.
    • Harper, J. K.
  • Source: Agronomy Journal
  • Volume: 104
  • Issue: 2
  • Year: 2012
  • Summary: Conservation tillage for corn (Zea mays L.) production has greatly reduced the soil erosion potential in these systems, but relies heavily on herbicides to manage weeds. Overreliance on herbicides can lead to the development of herbicide-resistant weed communities and increase the risk of ground and surface water contamination by residual herbicides. This study evaluates the integration of various mechanical soil/weed management implements and herbicide programs for surface residue cover, weed control, corn productivity, and economic net returns. A pre-plant vertical coulter/rotary harrow tended to control small annual weeds as well as a standard burn down herbicide program, but reduced surface residue cover by 15% compared to the no-till check treatments. The high residue rotary hoe had little effect on surface residue cover, but provided inconsistent early-season weed control. The high residue inter-row cultivator resulted in 23% residue cover compared to 50% in the no-till treatments, but reduced weed biomass by 53% without any supplemental residual herbicides and 88% with a banded residual herbicide compared to the weedy check treatment. Crop productivity and net return data suggest that integrating the vertical coulter/rotary harrow, high residue cultivator, and banded residual herbicide program could reduce herbicide ai rates by 70% and still achieve similar corn yields and economic returns as the herbicide intensive systems. Such integrated mechanical-chemical systems will increase the crop management complexity for farmers, which may hinder adoption. Soil erosion potential of the integrated systems requires further in-depth evaluation.
  • Authors:
    • Oztekin, M. E.
  • Source: Journal of Food, Agriculture and Environment
  • Volume: 10
  • Issue: 2 part 3
  • Year: 2012
  • Summary: Land use is an important global issue in terms of preserving the soils, agricultural crop production and farmers' economy as well as the other usage purposes. There are many useful approaches and tools for efficient determination of the land use types. In this study, distribution of different field crops and citrus orchards were monitored and determined for land use types (LUTs) using the low cost ASTER satellite images and GIS in Akarsu Irrigation District of Lower Seyhan Plain (9495 ha) in southern Turkey. Prior to parceling in the field, study area maps of 1:5000 scale were digitized by using ArcGIS software. The enhanced satellite images were overlaid onto the digitized parcel map for ground observations. The images were printed and checked for all crops of the fields. Commonly grown different field crops and orchards were mapped during the field work. A database for this research was established after an intensive field work. The crop types and their coordinates were determined and recorded during the field works. Five LUTs were identified in the study area, and corn and citrus were the most planted LUTs. Furthermore, suitability of soil series for LUTs was investigated; Canakci and Mursel soil series in the study area were found to be highly suitable for all LUTs. It was concluded that cost effective ASTER images could be potentially used for the determination of different crops and orchards which have different reflection values. However, the images must be obtained during the appropriate time period.
  • Authors:
    • Qi, X. F.
  • Source: Research of Agricultural Modernization
  • Volume: 33
  • Issue: 2
  • Year: 2012
  • Summary: Based on the statistical data of crop yields, cropland areas and agricultural inputs in the period from 2001 to 2010, the amounts of carbon absorption and emission of the farmland ecosystems in Dezhou were calculated, and the spatial-temporal variations and impact factors of carbon absorption and emission were analyzed. Carbon absorption of farmland ecosystem in Dezhou showed a trend from 2001-2010 and the carbon absorption of wheat, corn as the main food crops was significantly higher than other crops. The carbon emission showed the change of the increases after first reduces in Dezhou from 2001 to 2010. As the different the direction of agricultural development and the development characteristics in different counties there were different carbon emission; the carbon emission of chemical fertilizer was a larger proportion and a decreasing trend in the five ways of carbon emissions; carbon absorption was far greater than the amount of carbon emissions in Dezhou from 2001 to 2010 and there were a strong carbon sink of the farmland ecosystem. The correlation analysis results showed that carbon absorption was significantly positive correlated with the yields of wheat, corn and cotton. Significant positive correlations were observed between carbon emission and agrochemical inputs, power and fuels consumption, and cultivation and irrigation management.
  • Authors:
    • Hussein, M. S.
    • Elsebai, M. N.
    • Rihan, M. K.
  • Source: Arab Universities Journal of Agricultural Sciences
  • Volume: 20
  • Issue: 1
  • Year: 2012
  • Summary: Egypt depends on the Nile River as a major source of water, it provides about 76.3% of its water requirements, other water sources provides about 23.7% of total water requirements. Agriculture sector is the main consumer of water in Egypt as it consumed about 85.9% of the total actual consumption of water in 2009. The main problem of the present paper is the decrease in the efficiency of water use in Egyptian agriculture. The objective of paper is to assess the efficiency of water use in agriculture in the old and new land Egypt through the use of partial efficiency measures. Results showed that in average of the cost of irrigation per feddan during the period (1998-2009), that was for winter crops in the old lands as follows: 85.3, 105.8, 119.3, 127.3 pounds/feddan for faba bean, sugar beet, alfalfa sustained, wheat at a cost of irrigation per feddan of which respectively. For summer crops in old land cost was about 114.7, 129.5, 139.8, 156.2, 217.8, 606.1 pounds/feddan at a cost of, sesame, soybean, peanut, corn, rice, sugar cane, respectively. For the winter crops in the new lands irrigation cost per feddan was about L.E 99.3, 169.0 for garlic and onion respectively. Summer crops in the new lands irrigation costs for watermelon, cucumber, potatoes, eggplant, peppers, and tomatoes were as follows: L.E 92.4, 133, 138.7, 139.8, 157.7, 194.3 pounds/feddan respectively. The results of the statistical analysis of partial-efficiency measures showed that, according to the criterion of net revenue from the water unit - winter crops on the old land as follows: alfalfa, wheat, faba bean, and sugar beet. As for the summer crops of old land the results showed of the statistical estimate of the partial-efficiency measures that peanuts, corn, sesame, sugar cane, rice, soybeans respectively. In the new lands the results of statistical analysis for the partial-efficiency measures, according to the standard net return of the water unit for winter crops were garlic followed by the first crop of onions. As for the summer crops, the results of statistical analysis of partial-efficiency measures, according to the standard net return of the water unit came summer crops in the new lands, were as follows: potatoes, tomatoes, watermelon, cucumber, eggplant, pepper. The results in general indicated the necessaries of reconsidering the present structure of cropping pattern to increase the efficiency of irrigation water use.
  • Authors:
    • Pereira, L. S.
    • Alves, I.
    • Fernando, R. M.
    • Rodrigues, G. C.
    • Paredes, P.
    • Rosa, R. D.
    • Allen, R. G.
  • Source: Agricultural Water Management
  • Volume: 103
  • Year: 2012
  • Summary: This paper is the second of a two-part series, with the first part describing the SIMDualKc model, an irrigation scheduling simulation tool that employs the dual crop coefficient approach for calculating daily crop ET and then performs a water balance for a cropped soil. The model was applied, calibrated and validated for rainfed and basin irrigated maize (Coruche. Portugal), rainfed and surface irrigated wheat (Aleppo, Syria), and furrow irrigated cotton (Fergana, Central Asia). Results show good agreement between available soil water content observed in the field and that predicted by the model. Results indicate that the calibrated model does not tend to over- or underestimate available soil water over the course of a season, and that the model, prior to calibration, and using standard values for many parameters, also performed relatively well. After calibration, the average growing season maximum estimation errors were 10 mm for maize, 8 mm for winter wheat and 9 mm for cotton, i.e., respectively 3.6, 2.9 and 5.0% of total available water. Results indicate that the separation between evaporation and transpiration and the water balance calculation procedures are accurate enough for use in operational water management. The indicators used for assessing model performance show the model to accurately simulate the water balance of several crops subjected to a variety of irrigation management practices and various climate conditions. In addition, the model was applied to alternative irrigation management scenarios and related results are discussed aiming at assessing the model's ability to support the development of alternative active water management strategies.
  • Authors:
    • Li, Y.
    • Liu, G.
    • Yang, L.
    • Ma, L.
    • Xia, L.
  • Source: Transactions of the Chinese Society of Agricultural Engineering
  • Volume: 28
  • Issue: 14
  • Year: 2012
  • Summary: Protective management of arable slope land plays an important role in protection of land resource and aquatic environment in Three Gorges region, China. Base on the regional natural conditions and the utilization of the arable slope land, four tillage modes with H1 (rotation of wheat and maize, wheat intercropped with horse bean, less tillage and ridge cultivation), H2 (rotation of wheat and maize, with Vetiveria ziz anioides contour hedges intercropped at slop length interval of 5 m), H3 (rotation of wheat and maize, with alfalfa contour hedges intercropped at slop length interval of 5 m), H4 (rotation of wheat and maize, conventional management) were conducted from Oct. 2009 to Oct. 2011. The differences of apparent recovery efficiency and Agronomic efficiency of applied nitrogen and phosphorus between treatments were discussed, as well as nitrogen and phosphorus losses through slope land surface runoff were analyzed. The results showed that compared with H4, H1 increased phosphorus use efficiency by 0.06 kg/kg. No significant difference of biological and economic production, apparent recovery efficiency and agronomic efficiency of applied nitrogen and phosphorus was observed among H2, H3 and H4, which showed intercropping with Vetiveria ziz anioides or alfalfa contour hedges wouldn't lead to the reduction of production. Furthermore significant effects on reducing soil erosion and sediment phosphorus loss were observed for H1, H2 and H3. Compared with H4, and sediment losses for H1, H2 and H3 decreased by 48.46%, 52.26% and 58.59% respectively, and sediment phosphorus losses decreased by 30.58%, 47.70% and 44.58% respectively.
  • Authors:
    • Bergheaud, V.
    • Benoit, P.
    • Alletto, L.
    • Coquet, Y.
  • Source: Pest Management Science
  • Volume: 68
  • Issue: 4
  • Year: 2012
  • Summary: BACKGROUND: Sorption largely controls pesticide fate in soils because it influences its availability for biodegradation or transport in the soil water. In this study, variability of sorption and desorption of isoxaflutole (IFT) and its active metabolite diketonitrile (DKN) was investigated under conventional and conservation tillage. RESULTS: According to soil samples, IFT KD values ranged from 1.4 to 3.2 L kg -1 and DKN KD values ranged from 0.02 to 0.17 L kg -1. Positive correlations were found between organic carbon content and IFT and DKN sorption. IFT and DKN sorption was higher under conservation than under conventional tillage owing to higher organic carbon content. Under conservation tillage, measurements on maize and oat residues collected from the soil surface showed a greater sorption of IFT on plant residues than on soil samples, with the highest sorbed quantities measured on maize residues ( KD ~45 L kg -1). Desorption of IFT was hysteretic, and, after five consecutive desorptions, between 72 and 89% of the sorbed IFT was desorbed from soil samples. For maize residues, desorption was weak (
  • Authors:
    • Albuquerque, J.
    • Picolla, C.
    • Mafra, A.
    • Andrade, A.
    • Bertol, I.
  • Source: Ciencia Rural
  • Volume: 42
  • Issue: 5
  • Year: 2012
  • Summary: Suitable soil management is one of the bases for sustainability in agricultural systems. The study aimed to evaluate chemical properties of a Humic Dystrudept for 12 years under two tillage systems, with crops rotation and succession. The experiment was carried out in Lages, SC, under conventional tillage (CT) and no-till (NT), with rotation (r) and succession (s) cropping systems, using crop sequences of beans-fallow-maize-fallow-soybean in CTr; maize-fallow in CTs; beans-oats-maize-fodder radish-soybean-vetch in NTr; and maize-vetch in NTs. The experimental design was completely randomized with four replicates. The soil samples were collected in the layers 0-2.5, 2.5-5, 5-10 and 10-20 cm. The variables assessed were total organic carbon (TOC), calcium, magnesium, exchangeable aluminum, phosphorus, potassium, total nitrogen (TN) and water pH. The no-tillage system increased TOC and nutrient levels in comparison with conventional tillage, especially in the surface soil layer. Maize and vetch crop succession had higher TOC and TN contents in the surface soil layer compared to crop rotation under no-tillage.
  • Authors:
    • Matos, M.
    • Machineski, O.
    • Balota, E.
  • Source: REVISTA BRASILEIRA DE ENGENHARIA AGRICOLA E AMBIENTAL
  • Volume: 16
  • Issue: 5
  • Year: 2012
  • Summary: The objective of this work was to evaluate the changes in microbial biomass C, N and P due to the application of pig slurry under different soil tillage systems. The experiment was established in a clayey Oxisol, Eutrophic Red Latossol in Palotina, PR. Different quantities of pig slurry (0, 30, 60 and 120 m 3 ha -1 year -1) were applied to the soil prior to the summer and winter crop season under conventional tillage (CT) and no tillage (NT), in three replicates. The area was cultivated with soybean ( Glycine max L.) or maize ( Zea mays L.) in the summer and wheat ( Triticum sativum Lam.) or oat ( Avena sativa L.) in the winter. The soil samples were collected in March and October of 1998 and 1999 at depths of 0-5, 5-10 and 10-20 cm. The soil tillage and pig slurry application influenced the microbial biomass C, N and P. The microbial biomass and the microbial activity presented high sensibility to detect changes in the soil due to tillage and the application of pig slurry. The soil microbial biomass and C mic/C org relation increased as the quantity of applied pig slurry increased. The metabolic quotient under CT increased with depth while under NT it decreased. The soil microbial biomass was enriched in N and P under NT and as the quantity of applied pig slurry increased.
  • Authors:
    • Canbolat, O.
  • Source: KAFKAS UNIVERSITESI VETERINER FAKULTESI DERGISI
  • Volume: 18
  • Issue: 4
  • Year: 2012
  • Summary: The aim of this study was to compare the chemical composition, in vitro gas production, metabolizable energy (ME) organic matter digestibility (OMD), relative feed values (RFV) of the cereal forages from maize, sorghum, wheat, barley, oats, rye and triticale. Gas production were determined at 0, 3, 6, 12, 24, 48, 72 and 96 h and their kinetics were described using the equation y=a+b(1-e -ct). There were significant differences among cereal hay in terms of chemical composition (P