• Authors:
    • Zhang, P.
    • Yan, J. P.
    • Xu, H. L.
    • Zhao, X. F.
  • Source: Acta Pedologica Sinica
  • Volume: 48
  • Issue: 6
  • Year: 2011
  • Summary: After comparative analysis of the distribution characteristics of soil water and salt in farmlands (3 cotton fields and 1 orchard) and their shelterbelts in drip irrigation prevailing Kalamiji Oasis in the lower reaches of Tarim River, Northwest China through comparative tests and field monitoring, effects of the current drip irrigation pattern on farmlands within forest networks and their shelterbelts and main factors affecting salt-water dynamics in the soil within the forest network were studied and analyzed with the following conclusions obtained. (1) In Kalamiji oasis, the groundwater table in the fields lowers at a rate of 0.5 m a -1 as a result of popularization of drip irrigation and varies seasonally; it is relatively shallow in non-irrigation season and relatively deep in irrigation season; and over 1 m deeper in the latter than in the former. (2) As the impact of drip irrigation on soil never goes deeper than 80 cm, the irrigation supplies little water, almost nil, to groundwater, while the roots of farmland shelterbelt have to go deep into the soil to absorb water, thus leading to significantly lower soil water content in the shelterbelt than in farmland ( p
  • Authors:
    • Brown, M. G.
    • Merwin, I. A.
    • Atucha, A.
  • Source: HortScience
  • Volume: 46
  • Issue: 8
  • Year: 2011
  • Summary: Groundcover management systems (GMSs) are essential for fruit production, but very few long-term studies have evaluated orchard GMS sustainability. We evaluated four GMSs-pre-emergence soil-active herbicides (PreHerb), post-emergence herbicide (PostHerb), a turfgrass cover crop (Sod), and hardwood bark mulch (Mulch)-in an apple (Malus domestica Borkh.) orchard over 16 years of continuous observation. There were no consistent long-term trends in fruit yields among GMSs, although during the first 5 years, yields were lower in trees on Sod. Tree growth was greater in PostHerb and Mulch than in Sod during the first 5 years, and during the next decade, trees in Mulch plots were consistently larger than in other GMSs. Total soil nitrogen (N) and carbon (C) content, C-to-N ratios, and essential plant nutrients were much greater in the Mulch soil after 16 years of treatments. Long-term responses of trees to groundcover vegetation indicated that apple trees respond adaptively to compensate for weed and grass competition. Year-round elimination of surface vegetation with residual soil active herbicides may be unnecessary or even detrimental for orchard productivity and soil fertility in established orchards. Post-emergence herbicides that reduce weed competition primarily during the summer months may offer an optimal combination of weed suppression and soil conservation.
  • Authors:
    • Mohammed, S. M.
    • Fayed, T. A.
    • Esmail, A. F.
    • Abdou, N. A.
  • Source: The Bulletin of Faculty of Agriculture
  • Volume: 61
  • Issue: 1
  • Year: 2010
  • Summary: This investigation was carried out during the 2006 and 2007 growing seasons on a 3 year old Le-Conte pear trees ( Pyrus communis L. * Pyrus pyrifolia N.) grafted on Pyrus betulaefolia rootstock and planted at 5*5 meters apart (169 trees/faddan) in sandy soil under drip irrigation system, at El-Kassasien Horticultural Research Station, Ismailia Governorate. One source of organic fertilizers (compost) plus natural rocks (rock phosphate+feldspare), with or without biofertilizers (phosphorein and biogein) plus humic acid plus compost tea, were compared with chemical fertilization. Application of compost with biofertilizers plus humic add plus compost tea gave a better effect on all vegetative characteristics (growth rate of trunk diameter, shoot diameter, shoot length, number of leaves per shoot and leaf area) and chemical leaf constituents (leaf pigments, macro and micro elements, total carbohydrates, C/N ratio, protein contents) and yield compared to other organic treatments. Also vegetative growth, nutritional status and yield were significantly increased from the first till the second season indicating the accumulation effect of organic manure plus biofertilizers plus humic acid plus compost tea. Chemical fertilizer gave the highest vegetative and yield characteristics and leaf chemical contents compared to all organic rates with or without biofertilizers, humic acid and compost tea in the two seasons of study.
  • Authors:
    • Hoffmann, A. A.
    • Penfold, C. M.
    • Sharley, D. J.
    • Thomson, L. J.
    • Danne, A.
  • Source: Environmental Entomology
  • Volume: 39
  • Issue: 3
  • Year: 2010
  • Summary: Indigenous cover crops have the potential to promote an increase in natural enemies providing fortuitous control of pest species and other ecosystem services. We test this idea in a vineyard in south eastern Australia, where reduced water availability because of drought coupled with increased temperatures has generated interest in sustainable alternatives to the exotic perennial cover crops commonly planted. Three endemic perennial cover crops, comprising the grasses Austrodanthonia richardsonii and Chloris truncata and a mix of two saltbushes ( Atriplex semibaccata and Atriplex suberecta) were established as cover crops and compared with introduced oats ( Avena sativa). Abundance of a range of predators and parasitoids was higher in vines with native cover crops compared with the oat control. In addition, predation levels of sentinel eggs of a common vineyard pest, light brown apple moth ( Epiphyas postvittana), were increased in the native cover crops. However, the native cover crops also increased the abundance of some potential pest species. Native plants therefore have potential to increase abundance of beneficial invertebrates that assist in pest control, but need to be used carefully to ensure that they do not increase local pest problems.
  • Authors:
    • Garcia, P. A.
    • Benitez, E.
    • Ramos, M. E.
    • Robles, A. B.
  • Source: Applied Soil Ecology
  • Volume: 44
  • Issue: 1
  • Year: 2010
  • Summary: Frequent tillage has been widely used in rainfed orchards in SE Spain in order to impede weed establishment and to increase water reposition in the soil profile. However, this practice may lead to soil degradation by decreasing structural stability, organic carbon content and microbial activity. This work examines the effect of different cover crop managements and frequent tillage on soil physical, chemical and biological properties in almond orchards in SE Spain. Two cover crops (oat - Avena sativa L. and oat-vetch - Vicia sativa L.) with two fertilization managements (mineral and organic) and three harvesting regimes (grazing in mid May, hay in early June, and grain-straw in mid July) were compared to a frequently tilled orchard system (three or four tillages per year). Most parameters were sensitive to soil management. Wet aggregate stability, total organic carbon, total nitrogen, carbon:nitrogen ratio, phosphatase, and beta-glucosidase activities increased with cover crops, whereas the soil-water content declined, especially for the grain-straw treatment. The kind of fertilizer affected the available P content, which was higher for mineral fertilizer, and influenced the beta-glucosidase activity, which augmented for the organic fertilizer. Livestock dejections depressed phosphatase activity, and increased WSC and available P. This study suggests that cover crops in semiarid environments improve soil quality compared to frequently tilled management, by increasing the organic matter content, improving the chemical and physical fertility of the soil, and enhancing the soil biological activity. Only higher water extraction by the plants could affect the orchard development and/or productivity; however, early cover crop removal would minimize possible yield losses.
  • Authors:
    • Muller, C.
    • Amor, T.
  • Source: Agricultural Journal
  • Volume: 5
  • Issue: 2
  • Year: 2010
  • Summary: In this study, we estimate agricultural technology for Tunisian peasants, accounting for the crop choice of perasants and distinguishing inputs for individual crops such as: vegetable farming cereal and fruit-trees. The study employed the use of cross-section data from distinguishable irrigated crops survey conducted on a sample of 218 farmers frome 11 regions in Tunisia. The data were collected with the aid of structured questionnaire and were later analysed. The Cobb Douglass production frontier model is employed in order to analyse data collected. Among the irrigated crop farmers, the significant variables were: farmuar manuar fertiliser quantity, labor, mecanic traction and among of irrigated water applied. The estimated sigma square (sigma 2) and gamma (gamma) are widely significants for all irrigated crops and revealed that >85% of the variation in the Tunisian irrigated output among farmers in the study area are due to the differences in their efficiencies. Howerver, we find that predicted technical efficiency widely varies across farms and crops from an average of 54.7% for vegetable farming up to 80.6% for fruit-trees. The study also revealed the existing on inefficiency effects among the farmers as: education, farmer's age, irrigation techniques, lack of education, property of land.
  • Authors:
    • Garcia-Ruiz, J. M.
  • Source: Catena
  • Volume: 81
  • Issue: 1
  • Year: 2010
  • Summary: Soil erosion is a key factor in Mediterranean environments, and is not only closely related to geoecological factors (lithology, topography, and climatology) but also to land-use and plant cover changes. The long history of human activity in Spain explains the development of erosion landscapes and sedimentary structures (recent alluvial plains, alluvial fans, deltas and flat valleys infilled of sediment). For example, the expansion of cereal agriculture and transhumant livestock between the 16th and 19th centuries resulted in episodes of extensive soil erosion. During the 20th century farmland abandonment prevailed in mountain areas, resulting in a reduction of soil erosion due to vegetation recolonization whereas sheet-wash erosion, piping and gullying affected abandoned fields in semi-arid environments. The EU Agrarian Policy and the strengthening of national and international markets encouraged the expansion of almond and olive orchards into marginal lands, including steep, stony hill slopes. Vineyards also expanded to steep slopes, sometimes on new unstable bench terraces, thus leading to increased soil erosion particularly during intense rainstorms. The expansion of irrigated areas, partially on salty and poorly structured soils, resulted in piping development and salinization of effluents and the fluvial network. The trend towards larger fields and farms in both dry farming and irrigated systems has resulted in a relaxation of soil conservation practices.
  • Authors:
    • Risede,J. M.
    • Bouamer,S.
    • Petetin,C.
    • Lakhia,S.
    • Dorel,M.
  • Source: Fruits
  • Volume: 65
  • Issue: 2
  • Year: 2010
  • Summary: Introduction. In the French West Indies, farmers generally consider that periodical soil tillage is necessary to increase soil porosity and maintain high yield. However, in the non-tilled perennial banana plantations of the highlands, the soil exhibits better physical and biological properties than in the conventional banana plantations. To determine if tillage before banana planting is necessary for proper banana crop functioning and to assess the effect of tillage on soil quality, banana planting after conventional tillage was compared with no-till banana planting on crop residue mulch on an experimental plot. Materials and methods. Soil quality was assessed through indicators such as porosity, organic status, microbial biomass and structure of nematode communities. Crop functioning was assessed through plant growth, root distribution, and soil water and nitrogen availability. Results. We found that tillage reduced soil microbial biomass and the number of nematode functional guilds. Tillage had only a short-term effect on soil porosity and did not allow deeper extension of the root system. Although soil organic nitrogen mineralization was higher with conventional tillage, banana nitrogen nutrition was not better, probably because the high nitrogen fertilization offset the variations in availability of nitrogen from organic origin. We found that banana growth was better with no-till treatment. This could be explained by less drying out of soil due to the crop residue mulch left on the soil surface with no-till treatment. Conclusion. Relative to conventional tillage, no-till banana planting improved soil quality and crop performance.
  • Authors:
    • ERS
  • Volume: 2010
  • Year: 2010
  • Authors:
    • Gamzatov, I.
    • Muslimov, M.
  • Source: Kormoproizvodstvo
  • Issue: 12
  • Year: 2010
  • Summary: Continuous green fodder conveyor production system allows quality fodder supply during the grazing season. Field trials were conducted in Dagestan, the North Caucasus, Russia, with Red Steppe cattle. Data are tabulated on sowing dates and period of use of fodder crops, i.e. natural pastures, winter rape, winter rye + winter vetch, pea-oat + vetch-oat, regrowth of perennial grasses after hay cutting, Sudan grass, maize and maize + Sudan grass, sorghum, regrowth of Sudan grass and sorghum, maize sown after winter cereals grown for green fodder, maize and sorghum grown for silage for additional feed rations, winter rye after pea + oat, squash, pumpkin, fodder watermelon and fodder beet, and regrowth of natural pastures and meadows. The importance of natural pastures and drought resistant plants, such as sorghum crops, for production of high yield of fodder in dry conditions of Dagestan is considered.