• Authors:
    • Hosseini, S. M. B.
    • Jahansooz, M. R.
    • Heidari, H.
    • Chaichi, M. R.
  • Source: Annals of Biological Research
  • Volume: 3
  • Issue: 6
  • Year: 2012
  • Summary: The aim of the study was to determine the effect of alternate irrigation method and deficit irrigation on radiation use efficiency and forage quality of foxtail millet ( Setaria italica) under a double cropping system after barley ( Hordeum vulgar). Conventional furrow irrigation (M1) and alternate furrow irrigation (M2) methods and different deficit irrigation levels including 100, 85, 70 and 55% of crop water requirement (V1, V2, V3 and V4) were tested in a field experiment on the west of Tehran, Iran for 2 years (2008 and 2009). Results showed that alternate furrow irrigation with 85% of crop water requirement (M2V2) had the highest Absorption Ratio of Photosynthetically Active Radiation (PARAR) and Cumulative Absorption of Photosynthetically Active Radiation (PARCA) in 2008 (P
  • Authors:
    • Ma, Y. G.
    • Chen, X.
    • Li, Y. P.
    • Huang, Y.
  • Source: Agricultural Water Management
  • Volume: 107
  • Year: 2012
  • Summary: An integrated optimization method is developed for supporting agriculture water management and planning in Tarim River Basin, Northwest China. The developed method couples two-stage stochastic programming (TSP) with inexact quadratic program (IQP). The hydrological model is provided for forecasting the available irrigation water. The simulation system is then embedded into an optimization framework, where the objective is to maximize the system benefit for water resources management. The developed method can not only deal with nonlinearities in the cost/benefit objective and uncertainties expressed as probabilities and intervals, but also support the analysis of policy scenarios that are associated with economic penalties when the promised water-allocation targets are violated. A case study is conducted for Kaidu-kongque watershed in Tarim River Basin. The results obtained can help generate desired policies for water resources management with maximized economic benefit and minimized system-failure risk. (C) 2012 Elsevier B.V. All rights reserved.
  • Authors:
    • Finlay, L. A.
    • Weaver, T. B.
    • Hulugalle, N. R.
    • Lonergan, P.
  • Source: Soil Research
  • Volume: 50
  • Issue: 4
  • Year: 2012
  • Summary: Comparative studies of soil quality and energy use in two- and three-crop rotations in irrigated cotton ( Gossypium hirsutum L.) based cropping systems under varying stubble management practices in Australian Vertosols are sparse. Our primary objective was to quantify selected soil quality indices (salinity, sodicity, exchangeable cations, nitrate-N, pH), crop yields, and greenhouse gas emissions in four irrigated cotton-based cropping systems sown on permanent beds in a Vertosol with subsoil sodicity near Narrabri in north-western New South Wales. A secondary objective was to evaluate the efficacy of sowing vetch in rotation with cotton over a long period on the incidence of black root-rot in cotton seedlings. Results: presented in this report pertain to the period June 2005-May 2011. The experimental treatments were: cotton-cotton; cotton-vetch ( Vicia benghalensis L.); cotton-wheat ( Triticum aestivum L.), where wheat stubble was incorporated; and cotton-wheat-vetch, where wheat stubble was retained as in-situ mulch. Vetch was terminated during or just before flowering by a combination of mowing and contact herbicides, and the residues were retained as in-situ mulch. Soil pH, electrical conductivity (EC 1:5), Cl -, NO 3--N, exchangeable cations, exchangeable sodium percentage (ESP), electrochemical stability index (=EC 1:5/ESP), and EC 1:5/ESC (exchangeable sodium concentration) were evaluated in samples taken from the 0-1.2 m depth before sowing cotton during late September or early October of each year. Incidence of black root-rot was assessed 6 weeks after sowing cotton. Compared with sowing cotton every year, including wheat in cotton-based cropping systems improved cotton yield and reduced soil quality decline, emissions of carbon dioxide equivalents (CO 2-e) per unit area, and CO 2-e emissions per unit of cotton yield. Including vetch in the rotation was of negligible benefit in terms of yield and CO2-e emissions per unit of yield. The rate of soil quality decline was unaffected by including vetch in a cotton-wheat rotation but was accelerated when included in a cotton-cotton sequence. Among all cropping systems, soil quality was best with cotton-wheat and cotton-wheat-vetch but poorest with cotton-vetch. Although CO2-e emissions associated with growing 1ha of cotton could be reduced by 9% by growing vetch because of substituting fixed atmospheric N for N fertiliser derived from fossil fuels, this advantage was partly negated by the emissions from farming operations associated with growing a vetch crop. Relative to a two-crop rotation (one cotton-one rotation crop), negligible benefits in terms of yield, soil quality, greenhouse gas emissions, and black root-rot control accrued from a three-crop rotation (one cotton-two rotation crops). Incidence of black root-rot increased as the number of cotton crops sown increased. In addition to the cropping systems, soil quality indices and yield were significantly influenced by irrigation water quality and climate.
  • Authors:
    • Liu, H.
    • Liu, S.
    • Jiang, H.
  • Source: Chinese Journal Geophysics
  • Volume: 55
  • Issue: 2
  • Year: 2012
  • Summary: This study uses turbulence, net radiation and soil data from International Energy Balance Experiment (EBEX-2000) to study the characteristics of sensible and latent heat flux under thermal internal boundary layer which is induced by heterogeneous irrigation. Energy balance closure on irrigated days was compared with that on non-irrigated days. Schotanus correction and Webb correction were applied when calculating turbulence heat fluxes and their influences were also analyzed. During this research, eddy covariance method is used. Results indicate that turbulence heat fluxes in the surface layer are affected by thermal internal boundary layer resulted from heterogeneous irrigation, this interaction leads to a decrease of sensible heat flux and a oscillation of latent heat flux. This phenomenon is more significant at 8.7 m than that at 2.7 m. The existence of thermal internal boundary layer induced by heterogeneous irrigation result in a decreased energy balance ratio of 0.65; while with no internal thermal boundary layer, the energy balance ratio is close to 0.70. Schotanus correction results in a significant diminution of sensible heat flux in this experiment. The daily average of Schotanus correction reach up to -8 W/m(2), almost 4% of the net radiation. The daily average of Webb correction to latent heat flux is about 2 W/m(2), having slight influence on energy balance closure.
  • Authors:
    • Naidu, M. V. S.
    • Kailaimannan, R.
    • Venkaiah, K.
  • Source: Madras Agricultural Journal
  • Volume: 99
  • Issue: 4/6
  • Year: 2012
  • Summary: Some important physico-chemical parameters of irrigation water of guava orchards in Prakasam district were evaluated for the criteria of the irrigation water quality. Thirty water samples were collected from three different mandals of the Prakasam district. The present study revealed that pH was neutral to moderately alkaline, Electrical Conductivity (EC) was high, Sodium Adsorption Ratio (SAR) was low to medium and Residual Sodium Carbonate (RSC) was good to marginal. So, initiative must be taken to reduce salt accumulation in the soil through drainage and adopting the highly salt tolerant crops like cotton, mustard and tamarind for the better utilization of the land.
  • Authors:
    • Diker, K.
    • Sezen, S.
    • Tekin, S.
    • Unlu, M.
    • Onder, S.
    • Kanber, R.
  • Source: Turkish Journal of Agriculture and Forestry
  • Volume: 36
  • Issue: 1
  • Year: 2012
  • Summary: In this study, the water saving and conservation potential of various furrow irrigation management techniques for irrigated cotton were compared. Conventional every-furrow irrigation with open-end furrows (EFO) and blocked-end furrows (EFB), and alternate every-other-furrow management with open-end furrows (AFO) and blocked-end furrows (AFB), were considered. Considerable seasonal water savings were obtained with AFO and AFB flows, on average from 717 mm to 906 mm, respectively, when compared to EFO. Alternate furrows showed the ability to reduce tailwater runoff considerably. When compared with EFO, water use was reduced by 9063 m(3) ha(-1) (60%) using AFB and 7167 m(3) ha(-1) (48%) using AFO, with decreases in yield of 765 kg ha(-1) (27%) and 492 kg ha(-1) (17%), respectively. Similarly, average water use efficiencies were 0.36 kg m(-3) for AFB and 0.31 kg m(-3) for AFO, compared to 0.20 kg m(-3) for EFO. Results showed the possibility of applying alternate-flow furrow management techniques for water conservation in cotton irrigation. Additionally, the alternate furrow method could also be considered as a deficit irrigation approach in the Harran Plain.
  • Authors:
    • Liu, S.
    • Jiang, S.
    • Hu, W.
    • Wan, S.
    • Wang, R.
    • Kang, Y.
  • Source: Agricultural Water Management
  • Volume: 109
  • Year: 2012
  • Summary: Due to the mismanagement of water and fertilizer application, cotton cultivation in Xinjiang Northwest China is faced with the problems of soil deterioration and groundwater table ascension. This study was conducted to evaluate the effects of different levels of water applied through drip irrigation on cotton yield and water use in an arid region of Northwest China. The experiment included five water treatments in which the soil matric potential (SMP) at a depth of 20 cm was controlled higher than -10 kPa (S1), -20 kPa (S2), -30 kPa (S3), -40 kPa (S4), and -50 kPa (S5) after cotton was established. The results revealed that the highest cotton evapotranspiration (ETc) was achieved under S1 (-10 kPa) treatment and the ETc, deep percolation and the ratio of deep percolation with irrigation water all increased with increasing SMP threshold. After three years experiment, no salt accumulation in surface soil layer was found under our irrigation schedule. The highest seed cotton yield was obtained when the SMP threshold was controlled above -30 kPa in 2008, and -20 kPa in 2009 and 2010. Moreover, the highest yield obtained after 3 years was 42% higher than the average yield achieved by local farmers in the area. Additionally, the water use value (WUE and IWUE) tended to increase as the SMP threshold decreased in 2009 and 2010. Considering the cotton yield and the impact of irrigation on the underground water table, an SMP higher than -20 kPa at 20 cm can be used as an indicator for cotton drip irrigation scheduling and agronomic practices in this area to help alleviate the dangerous increase in the water table while increasing the cotton seed yield. (C) 2012 Elsevier B.V. All rights reserved.
  • Authors:
    • Rathore, P.
    • Singh, H.
    • Singh, K.
    • Gumber, R. K.
  • Source: Journal of Cotton Research and Development
  • Volume: 26
  • Issue: 1
  • Year: 2012
  • Summary: A field experiment was conducted at PAU, Regional Research Station, Faridkot during kharif 2009 and 2010 to evaluate the performance of two arboreum varieties (FDK 124 and LD 694 as check) under two plant geometries (67.5*45 and 67.5*60 cm) and three nutrient levels (i.e. 56.25, 22.5 kg NP/ha; 75, 30 kg NP/ha and 93.75, 37.5 kg NP/ha). New variety FDK 124 yielded 24.5 per cent significantly higher seed cotton yield (2814 kg/ha) as compared to LD 694 (2260 kg/ha) due to significantly more number of bolls. Pooled data further indicated that significantly higher seed cotton yield was recorded under closer geometry of 67.5*45 cm (2613 kg/ha) than wider plant geometry of 67.5*60 cm (2460 kg/ha). Though, yield attributing parameters such as bolls/plant were statistically improved in wider as compared to closer spacing but it could not compensate yield due to significantly higher plant population in the later case. Among nutrient levels, similar seed cotton yield was recorded with application of 93.75, 37.5 kg NP/ha (2688 kg/ha) and 75, 30 Kg NP/ha (2587 kg/ha) but both were significantly better than that of 56.25, 22.5 kg NP/ha (2335 kg/ha). So, 75, 30 kg NP/ha and plant geometry of 67.5*45 cm seemed to be ideal for new variety FDK 124 for realizing higher productivity under the specific agro climatic conditions of Faridkot.
  • Authors:
    • Vanham, D.
    • Laghari, A. N.
    • Rauch, W.
  • Source: Hydrology and Earth System Sciences
  • Volume: 16
  • Issue: 4
  • Year: 2012
  • Summary: The Indus basin is one of the regions in the world that is faced with major challenges for its water sector, due to population growth, rapid urbanisation and industrialisation, environmental degradation, unregulated utilization of the resources, inefficient water use and poverty, all aggravated by climate change. The Indus Basin is shared by 4 countries - Pakistan, India, Afghanistan and China. With a current population of 237 million people which is projected to increase to 319 million in 2025 and 383 million in 2050, already today water resources are abstracted almost entirely (more than 95% for irrigation). Climate change will result in increased water availability in the short term. However in the long term water availability will decrease. Some current aspects in the basin need to be re-evaluated. During the past decades water abstractions - and especially groundwater extractions - have augmented continuously to support a rice-wheat system where rice is grown during the kharif (wet, summer) season (as well as sugar cane, cotton, maize and other crops) and wheat during the rabi (dry, winter) season. However, the sustainability of this system in its current form is questionable. Additional water for domestic and industrial purposes is required for the future and should be made available by a reduction in irrigation requirements. This paper gives a comprehensive listing and description of available options for current and future sustainable water resources management (WRM) within the basin. Sustainable WRM practices include both water supply management and water demand management options. Water supply management options include: (1) reservoir management as the basin is characterised by a strong seasonal behaviour in water availability (monsoon and meltwater) and water demands; (2) water quality conservation and investment in wastewater infrastructure; (3) the use of alternative water resources like the recycling of wastewater and desalination; (4) land use planning and soil conservation as well as flood management, with a focus on the reduction of erosion and resulting sedimentation as well as the restoration of ecosystem services like wetlands and natural floodplains. Water demand management options include: (1) the management of conjunctive use of surface and groundwater; as well as (2) the rehabilitation and modernization of existing infrastructure. Other demand management options are: (3) the increase of water productivity for agriculture; (4) crop planning and diversification including the critical assessment of agricultural export, especially (basmati) rice; (5) economic instruments and (6) changing food demand patterns and limiting post-harvest losses.
  • Authors:
    • Laurie, R. N.
    • Jaarsveld, P. J. van
    • Faber, M.
    • Laurie, S. M.
    • Plooy, C. P. du
    • Modisane, P. C.
  • Source: Scientia Horticulturae
  • Volume: 142
  • Year: 2012
  • Summary: beta-Carotene rich orange-fleshed sweet potatoes are increasingly used in community-based interventions aimed at addressing vitamin A deficiency, but are often cultivated in marginal soils and with sub-optimal agricultural inputs. The aim of the study was to determine (i) beta-carotene content, beta-carotene yield and water productivity at increments of water application, and, (ii) beta-carotene content and beta-carotene yield at increments of chemical fertilizer application for orange-fleshed sweet potato in separate field trials. beta-Carotene content at the low irrigation treatment was between 15 and 34% higher than at optimal irrigation treatment. Increased water application brought about a two-fold increase in beta-carotene yield per unit area. The best combination of beta-carotene yield and water productivity (g beta-carotene ha -1 mm -1 water applied) was achieved at the intermediate (60%) irrigation treatment. Calculations showed that 1 ha of orange-fleshed sweet potato produced at the intermediate water application at yield level of 24.6-28.4 t ha -1, can potentially provide 452-730 households (of six persons) with an adequate amount of vitamin A over a period of 180 days. beta-Carotene content was 14% higher for both intermediate (50%) and high (100%) fertilizer treatments, compared to the 0% fertilizer treatment. beta-Carotene yield increased two-fold at the intermediate and four-fold at the high fertilization treatment. This paper provides novel information on the effect of irrigation on beta-carotene yield, as well as beta-carotene water productivity in orange-fleshed sweet potato. Follow-up research on a range of varieties is suggested toward obtaining recommendations for broad application in vitamin A crop-based interventions to optimize the beta-carotene yield in orange-fleshed sweet potato.