• Authors:
    • Halsema, G. E. van
  • Source: Wageningen Universiteit. Promotor: Prof. L.F. Vincent, co-promotor(en): Dr. D.H. Murray-Rust. - Wageningen : G.E. van Halsema, 2002. Source: OAI
  • Year: 2002
  • Summary: This thesis contains nine major chapters investigating the attempts undertaken over the past 20 years in the North West Frontier Province (NWFP), Pakistan, to develop and introduce modern irrigation water delivery services in large-scale government run irrigation systems. The second chapter presents a historical analysis of the development of the large scale canal irrigation systems in the Indus basin during British colonial time. The analysis focuses on how the concept of protective irrigation was developed and refined over time by the irrigation authorities. The next chapter discusses the era after independence of Pakistan till the start of the modernization programme in NWFP around 1980. It focuses on the changing scenarios of irrigation management and development in the Indus basin, that has resulted from substantial changes in its institutional and political context. Several case studies are presented in the next chapters: design and implementation of a responsive water supply services in the Mardan-SCARP (Salinity Control and Reclamation Project) project (Chapter 4); the adaption of water management strategies in the newly remodelled Lower SWAT canal (Chapter 5); the application of crop-based irrigation operation for the project in Chasma Right Bank Canal (Chapter 6); and the Swabi-SCARP and Pehur High Level Canal (PHLC) projects that foresee new irrigation developments in the Peshawar Vale, making the use of the water share still available to NWFP after the Indus Water Appointment Act (Chapter 7). The next chapter presents an epilogue to the modernization programme, with the institutional reform programme for the irrigation sector in Pakistan, that was initiated in 1994 and finally got underway in 1999/2000. Finally, some general conclusions are drawn in chapter nine on the function of engineering and designed physical systems in the wider system of irrigation water management.
  • Authors:
    • Power, J. F.
    • Wiese, R.
    • Flowerday, D.
  • Source: Journal of Environmental Quality
  • Volume: 30
  • Issue: 6
  • Year: 2001
  • Summary: The U.S. Department of Agriculture funded the Management Systems Evaluation Area (MSEA) research project in 1990 to evaluate effectiveness of present fanning systems in controlling nitrate N in water resources and to develop improved technologies for farming systems. This paper summarizes published research results of a five-year effort. Most research is focused on evaluating the effectiveness of farming system components (fertilizer, tillage, water control, cropping systems, and soil and weather variability). The research results show that current soil nitrate tests reliably predict fertilizer N needed to control environmental and economic risks for crop production. A corn (Zea mays L.)-soybean [Glycine mar (L.) Merr.] rotation usually controls risk better than continuous corn, but both may result in unacceptable nitrate leaching. Reduced tillage, especially ridge-till, is better than clean tillage in reducing risk. The drainage controls nitrate in ground water, but discharge may increase nitrate in surface waters. Sprinkler irrigation systems provide better water control than furrow irrigation because quantity and spatial variability of applied water is reduced. Present farming systems have two major deficiencies: (i) entire fields are managed uniformly, ignoring inherent soil variability within a field; and (ii) N fertilizer rates and many field practices are selected assuming normal weather for the coming season. Both deficiencies can contribute to nitrate leaching in parts of most fields.
  • Authors:
    • Thompson, K.
    • Kunugi, A.
    • Kawanabe, L. M.
    • Thompson, A.
    • Sparks, R. T.
    • Riggenbach, R. R.
    • Shaffer, M. J.
    • Follett, R. F.
    • Stuebe, A.
    • Duke, H. R.
    • Dillon, M. A.
    • Ristau, R. J.
    • Delgado, J. A.
  • Source: Communications in Soil Science and Plant Analysis
  • Volume: 32
  • Issue: 7-8
  • Year: 2001
  • Summary: Cropping systems grown over sandy coarse soils are susceptible to nutrient leaching due to local thunderstorms and irrigation. Additionally, erosion can contribute to removal of nutrients, soil organic matter, and fine particles. Balancing nutrients for these systems while protecting water and soil quality requires best management practices (BMPs). Crop rotations with deeper rooted small grains and winter cover crops reduced potential losses of fine particles, soil organic matter, nitrogen, and other nutrients due to wind erosion and protected soil and water quality. The cropping system N status can be monitored by assessing chlorophyll, sap NO3--N concentrations and N indexes of the canopy. The Nitrogen Leaching Economic Analysis Package (NLEAP) model simulated residual soil NO3--N and soil water and showed that there is potential to use precision farming to improve NUE. Simulations of the system showed that BMPs increased NUE and that NO3--N can potentially be removed from the shallow underground water table protecting water quality. These results show that with the application of models, and tools to monitor the N status of the aboveground canopy, such as chlorophyl readings, sap NO3--N concentrations, N indices, and other new technologies such as precision farming and remote sensing, nutrient use efficiency in the new millennium will be significantly increased, environmental quality will be conserved, and product quality will be improved at the farm level for the benefit of producers, processors and consumers.
  • Authors:
    • Follett, R. F.
  • Source: Soil & Tillage Research
  • Volume: 61
  • Issue: 1-2
  • Year: 2001
  • Summary: One of the most important terrestrial pools for carbon (C) storage and exchange with atmospheric CO2 is soil organic carbon (SOC). Following the advent of large-scale cultivation, this long-term balance was disrupted and increased amounts of SOC were exposed to oxidation and loss as atmospheric CO2. The result was a dramatic decrease in SOC. If amounts of C entering the soil exceed that lost to the atmosphere by oxidation, SOC increases. Such an increase can result from practices that include improved: (1) tillage management and cropping systems, (2) management to increase amount of land cover, and (3) efficient use of production inputs, e.g. nutrients and water. Among the most important contributors is conservation tillage (i.e., no-till, ridge-till, and mulch-tillage) whereby higher levels of residue cover are maintained than for conventional-tillage. Gains in amount of land area under conservation tillage between 1989 and 1998 are encouraging because of their contributions to soil and water conservation and for their potential to sequester SOC. Other important contributors are crop residue and biomass management and fallow reduction. Collectively, tillage management and cropping systems in the US are estimated to have the potential to sequester 30-105 million metric tons of carbon (MMTC) yr-1. Two important examples of management strategies whereby land cover is increased include crop rotations with winter cover crops and the conservation reserve program (CRP). Such practices enhance SOC sequestration by increasing the amount and time during which the land is covered by growing plants. Crop rotations, winter cover crops, and the CRP combined have the potential to sequester 14-29 MMTC yr-1. Biomass production is increased by efficient use of production inputs. Optimum fertility levels and water availability in soils can directly affect quantity of crop residues produced for return to the soil and for SOC sequestration. Nutrient inputs and supplemental irrigation are estimated to have the potential to sequester 11-30 MMTC yr-1. In the future, it is important to acquire an improved understanding of SOC sequestration processes, the ability to make quantitative estimates of rates of SOC sequestration, and technology to enhance these rates in an energy- and input-efficient manner. Adoption of improved tillage practices and cropping systems, increased land cover, and efficient use of nutrient and water inputs are examples where such information is necessary.
  • Authors:
    • Morse, R. D.
    • Miyao, E. M.
    • Temple, S. R.
    • Lanini, W. T.
    • Mitchell, J. P.
    • Herrero, E. V.
    • Campiglia, E.
  • Source: California Agriculture
  • Volume: 55
  • Issue: 1
  • Year: 2001
  • Summary: The efficacy of no-till systems in conserving soil moisture and improving water infiltration under furrow irrigation was evaluated during 1997 and 1998 in California, USA. Two grass/legume mixtures, i.e. triticale/lana woolypod vetch (* Triticosecale/ Vicia dasycarpa [ V. villosa]) and rye/lana woolypod vetch ( Secale cereale/ V. dasycarpa), were used as cover cop mulches in no-till treatments, and compared with a winter fallow treatment with pre-plant herbicide (fallow +h) and a fallow control treatment with no herbicide (fallow -h). Tomato cv. Halley 3155 plants were transplanted in April 1997 and 1998, sprinkle irrigated during the first 6 weeks after transplanting, and furrow irrigated thereafter until 3 weeks before harvest. During 1997, soil water content between 0 and 78 inches did not differ among treatments, while soil water content during the 1997/98 winter was higher under the fallow +h than the cover crop treatments until cover crop termination. Soil water content of cover crop treatments in shallower soil layers (18 and 42 inches) was significantly lower than fallow treatments at the end of the winter. During the 1998 tomato crop season, soil water content between 0 and 90 inches was greater under the triticale and rye mulches than the fallow +h, beginning the 3rd week after furrow irrigations were started. Soil moisture in the shallower layers was also affected by cover crop mulches. In the 42-inch depth increment, there was significantly higher water content under the cover crops than under the fallow +h from about 1 month after the first furrow irrigation until 2 weeks before the last irrigation. Changes in soil water content during furrow irrigation under the fallow +h treatment appeared to be more pronounced than under the triticale or rye surface mulches. Soil compaction in the fallow +h treatment was higher than under the cover crop mulches for most of the 0.6-inch intervals, especially below 1 foot, but differences were significantly higher only for the 3, 3.6, 4.2, 17, 18, and 24-inch depth, but lower from the surface to 2.4 inches. Soil carbon was significantly higher (by 14 and 18%) under triticale and rye, respectively, compared with the fallow +h treatment. The number of earthworms was also higher in no-till (2.1 earthworms per square foot) than in the fallow treatments (0.6 earthworms). Tomato canopy growth did not reach 100% cover in either 1997 or 1998, while tomato plant growth, assessed by measuring the photosynthetically active radiation intercepted by the canopy, did not differ in the triticale, rye, and fallow +h system in either 1997 or 1998. Results showed that the no-till mulch system enhanced water infiltration and soil water conservation.
  • Authors:
    • Choudhary, A.
    • Akramkhanov, A.
    • Pulatov, A.
  • Source: Conservation agriculture, a worldwide challenge. First World Congress on conservation agriculture, Madrid, Spain, 1-5 October, 2001. Volume 2
  • Year: 2001
  • Summary: This paper describes the status of agriculture and environmental issues in Uzbekistan and other Central Asian states. The paper also outlines the recent research and development project being conducted in Uzbekistan to promote conservation agriculture technologies for wheat and cotton production. No-tillage and bed planting technologies were trialled for the first time in Uzbekistan to grow winter wheat at the Tashkent Institute of Irrigation and Agricultural Mechanisation Engineers Research Farm. These were compared to conventionally grown wheat. Wheat yield obtained was 3.44, 3.96 and 3.57 t/ha in no-till, bed planting and conventional fields respectively. These results suggest a high potential for irrigated wheat crop production with the use of such technologies in Uzbekistan.
  • Authors:
    • Ahmed, A. S.
    • Abd El-Aal, R. S.
    • Soltan, S. A.
    • Ismail, M. A.
  • Source: Annals of Agricultural Science, Moshtohor
  • Volume: 39
  • Issue: 4
  • Year: 2001
  • Summary: To investigate the capability of plants to utilize the different soil nutrients and hence their crop productivity and water use efficiency (WUE), a field experiment was undertaken in Ismalia, Egypt, during 1999 summer season. Maize, as an indicator plant, was grown under both surface drip irrigation (SDI) and subsurface drip irrigation (SSDI). Under both irrigation systems, 3 regimes of irrigation water were applied, i.e. 60, 80 and 100% of water consumptive use of maize in the area. Soil samples were taken every other day one time just before irrigation and another at ~7 h after irrigation to follow up the movement and distribution of soluble salts and moisture in the soil profile. The soluble salt accumulation phenomenon was followed up through the uppermost 10 cm of soil surface while the soil moisture was estimated every 10 cm of soil downward till a 60 cm soil depth. Soil salinity tended to increased in the soil surface with decreasing the irrigation regime under both irrigation systems. The soil moisture content retained was higher under SSDI than under SDI. Soil available N, P and K tended to increased as the irrigation regime decreased, while available Fe, Mn and Zn in the soil decreased with decreasing the irrigation regime. The SDI significantly increased the maize grain contents of N and P compared to SSDI. Grain and straw yields increased significantly under SSDI compared with SDI. The highest grain or straw yield was recorded with the highest rate of irrigation regime. The total contents (uptake) of N, P and K as well as Fe, Mn and Zn in maize grain increased significantly under SSDI compared with SDI. The medium level of irrigation regime (80%) recorded higher values of both maize grain and straw yields under SSDI than under SDI. The WUE was significantly higher under SSDI compared to SDI. It decreased with decreasing irrigation regime.
  • Authors:
    • Christoffoleti, P. J.
    • Shiratsuchi, L. S.
  • Source: The BCPC Conference: Weeds, 2001, Volume 1 and Volume 2. Proceedings of an international conference held at the Brighton Hilton Metropole Hotel, Brighton, UK, 12-15 November 2001
  • Year: 2001
  • Summary: Weed control represents a high percentage of the production costs in no-till systems in Brazil, and chemical control using herbicides is by far the most important method used. However, the weeds are not uniformly or randomly distributed but have a patchy distribution such that the broadcast application of herbicides can spray post-emergence herbicides in areas where there are no weeds. Therefore, this work had the objective of demonstrating the potential of saving of herbicides in the no-till production system of the Brazilian agriculture, based on weed seed bank and weed seedling maps. The density of several weeds was mapped using a backpack DGPS and laptop computer. Experiments were conducted in Sao Paulo [date not given] in a 17.7-ha field of no-till maize under centre pivot irrigation. Seed bank data was determined from soil cores collected from a depth of 0.05 m in the centre of a 20*20 m grid and emergence assessments in a greenhouse. On the same grid size, weed seedlings were counted in 0.25 m 2 quadrats. Resultant maps showed a high weed density in the seed bank over just 4.67 ha, which was only 26% of the field area. The seedling maps demonstrated that grasses and broadleaf weeds had different distributions with broadleaf weeds occupying 12.6% of the field and grasses 87.4%. The targeting of herbicide to weed patches using pre- and postemergent herbicides has the potential to reduce herbicide use compared to broadcast application giving both environmental and economic advantages.
  • Authors:
    • Faour, K.
  • Source: Farm Budget Handbook, Southern NSW - Irrigated Winter Crops 2001
  • Year: 2001
  • Summary: This handbook presents gross margin budgets for irrigated winter crops and pasture establishment to assist landholders in the Murrumbidgee and Murray valleys (southern New South Wales, Australia) plan for the 2001 winter cropping season.
  • Authors:
    • Follett, R. F.
  • Source: Soil & Tillage Research
  • Volume: 61
  • Issue: 1/2
  • Year: 2001
  • Summary: One of the most important terrestrial pools for carbon (C) storage and exchange with atmospheric CO 2 is soil organic carbon (SOC). Following the advent of large-scale cultivation, this long-term balance was disrupted and increased amounts of SOC were exposed to oxidation and loss as atmospheric CO 2. The result was a dramatic decrease in SOC. If amounts of C entering the soil exceed that lost to the atmosphere by oxidation, SOC increases. Such an increase can result from practices that include improved: (1) tillage management and cropping systems, (2) management to increase amount of land cover, and (3) efficient use of production inputs, e.g. nutrients and water. Among the most important contributors is conservation tillage (i.e., no-till, ridge-till, and mulch-tillage) whereby higher levels of residue cover are maintained than for conventional-tillage. Gains in amount of land area under conservation tillage between 1989 and 1998 are encouraging because of their contributions to soil and water conservation and for their potential to sequester SOC. Other important contributors are crop residue and biomass management and fallow reduction. Collectively, tillage management and cropping systems in the US are estimated to have the potential to sequester 30-105 million metric tonnes of carbon (MMTC) year -1. Two important examples of management strategies whereby land cover is increased include crop rotations with winter cover crops and the conservation reserve programme (CRP). Such practices enhance SOC sequestration by increasing the amount and time during which the land is covered by growing plants. Crop rotations, winter cover crops, and the CRP combined have the potential to sequester 14-29 MMTC year -1. Biomass production is increased by efficient use of production inputs. Optimum fertility levels and water availability in soils can directly affect quantity of crop residues produced for return to the soil and for SOC sequestration. Nutrient inputs and supplemental irrigation are estimated to have the potential to sequester 11-30 MMTC year -1. In the future, it is important to acquire an improved understanding of SOC sequestration processes, the ability to make quantitative estimates of rates of SOC sequestration, and technology to enhance these rates in an energy- and input-efficient manner. Adoption of improved tillage practices and cropping systems, increased land cover, and efficient use of nutrient and water inputs are examples where such information is necessary.