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Registro Completo |
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Biblioteca(s): |
Embrapa Agropecuária Oeste; Embrapa Meio Norte / UEP-Parnaíba. |
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Data corrente: |
21/05/1997 |
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Data da última atualização: |
09/07/2003 |
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Autoria: |
KIJNE, J. W. |
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Título: |
Water and salinity balances for irrigated agriculture in Pakistan. |
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Ano de publicação: |
1996 |
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Fonte/Imprenta: |
Colombo: IIMI, 1996. |
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Páginas: |
17 p. |
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Série: |
(IIMI. Research Report, 6). |
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Idioma: |
Inglês |
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Conteúdo: |
Water and salt balances are calculated for three irrigated areas in Pakistan, which differ in water availability, amounts of water pumped for irrigation from groundwater, and salt content of the irrigation water. One of the sample areas is the Chasma Right Bank Canal (CRBC) command area in the North-West Frontier Province and the other two are in the Punjab, in the command areas of the Gugera Branch Canal and the Fordwah/Eastern Sadiqia Irrigation System. The input data for the water and salt balances were obtained from actual field measurements and observations over a number of years in sample watercourses in the irrigation systems. Some simplifications were made in the input values because of considerable spatial and temporal variations in several of the input parameters. A sensitivity analysis was carried out to identify the most critical input parameters. Results indicate that the net flow to groundwater in the Punjab sites is much less during Kharif (summer or monsoon season) than during rabi (winter). It is concluded from the analysis that current irrigation and agronomic practices are not sustainable. In the CRBC site, considerable groundwater recharge occurs, which in the absence of groundwater pumping leads to rising water tables, waterlogging, and salinity. At present, while the second and third stages of the project are still being developed, farmers in the area of the first stage receive more water than the crops require. The only feasible solution appears to be to limit the irrigation supply to farmers and to reduce the area under rice. In the sample irrigation areas of the Punjab, groundwater is mined, water tables drop, and salt continues to be added to the root zone because of the relatively high proportion of irrigation water derived from pumped groundwater. If the current high crop intensities are maintained, further degradation of land and water resources is inevitable. Additional studies, including regional groundwater flow modeling, are required to predict the rate of expected soil degradation. MenosWater and salt balances are calculated for three irrigated areas in Pakistan, which differ in water availability, amounts of water pumped for irrigation from groundwater, and salt content of the irrigation water. One of the sample areas is the Chasma Right Bank Canal (CRBC) command area in the North-West Frontier Province and the other two are in the Punjab, in the command areas of the Gugera Branch Canal and the Fordwah/Eastern Sadiqia Irrigation System. The input data for the water and salt balances were obtained from actual field measurements and observations over a number of years in sample watercourses in the irrigation systems. Some simplifications were made in the input values because of considerable spatial and temporal variations in several of the input parameters. A sensitivity analysis was carried out to identify the most critical input parameters. Results indicate that the net flow to groundwater in the Punjab sites is much less during Kharif (summer or monsoon season) than during rabi (winter). It is concluded from the analysis that current irrigation and agronomic practices are not sustainable. In the CRBC site, considerable groundwater recharge occurs, which in the absence of groundwater pumping leads to rising water tables, waterlogging, and salinity. At present, while the second and third stages of the project are still being developed, farmers in the area of the first stage receive more water than the crops require. The only feasible solution appears to be ... Mostrar Tudo |
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Palavras-Chave: |
Paquistão. |
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Thesagro: |
Agricultura; Água; Balanço Hídrico; Irrigação; Manejo; Salinidade. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 02592nam a2200217 a 4500
001 1245639
005 2003-07-09
008 1996 bl uuuu u0uu1 u #d
100 1 $aKIJNE, J. W.
245 $aWater and salinity balances for irrigated agriculture in Pakistan.
260 $aColombo: IIMI$c1996
300 $a17 p.
490 $a(IIMI. Research Report, 6).
520 $aWater and salt balances are calculated for three irrigated areas in Pakistan, which differ in water availability, amounts of water pumped for irrigation from groundwater, and salt content of the irrigation water. One of the sample areas is the Chasma Right Bank Canal (CRBC) command area in the North-West Frontier Province and the other two are in the Punjab, in the command areas of the Gugera Branch Canal and the Fordwah/Eastern Sadiqia Irrigation System. The input data for the water and salt balances were obtained from actual field measurements and observations over a number of years in sample watercourses in the irrigation systems. Some simplifications were made in the input values because of considerable spatial and temporal variations in several of the input parameters. A sensitivity analysis was carried out to identify the most critical input parameters. Results indicate that the net flow to groundwater in the Punjab sites is much less during Kharif (summer or monsoon season) than during rabi (winter). It is concluded from the analysis that current irrigation and agronomic practices are not sustainable. In the CRBC site, considerable groundwater recharge occurs, which in the absence of groundwater pumping leads to rising water tables, waterlogging, and salinity. At present, while the second and third stages of the project are still being developed, farmers in the area of the first stage receive more water than the crops require. The only feasible solution appears to be to limit the irrigation supply to farmers and to reduce the area under rice. In the sample irrigation areas of the Punjab, groundwater is mined, water tables drop, and salt continues to be added to the root zone because of the relatively high proportion of irrigation water derived from pumped groundwater. If the current high crop intensities are maintained, further degradation of land and water resources is inevitable. Additional studies, including regional groundwater flow modeling, are required to predict the rate of expected soil degradation.
650 $aAgricultura
650 $aÁgua
650 $aBalanço Hídrico
650 $aIrrigação
650 $aManejo
650 $aSalinidade
653 $aPaquistão
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Registro original: |
Embrapa Agropecuária Oeste (CPAO) |
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