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The downstream plain of the Yellow River is experiencing some of the most severe groundwater depletion in China. Although the Chinese government has issued policies to ensure that the Yellow River can provide enough irrigation waters for this region, groundwater levels continue to decrease. Yucheng City was selected as a case study. A new method wa...
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... changes as annual rainfall changes. Gross water use was estimated based on various values of N under different probabilities of irrigation (Table 2). Table 2. Mean gross irrigation norm with flood irrigation in the study area for winter wheat. ...Context 2
... water use was estimated based on various values of N under different probabilities of irrigation (Table 2). Table 2. Mean gross irrigation norm with flood irrigation in the study area for winter wheat. ...Context 3
... changes as annual rainfall changes. Gross water use was estimated based on various values of N under different probabilities of irrigation ( Table 2). The improved Penman-Monteith equation was used to calculate daily potential evapotranspiration (Equation (2)) [11]: ...Context 4
... a 75% irrigation probability, the river-irrigation norm is 5355 m 3 /ha ( Table 2). The annual amount of water that is used for river irrigation of farmland is 8.2 × 10 8 m 3 ( Table 7). ...Context 5
... annual amount of water that is used for river irrigation of farmland is 8.2 × 10 8 m 3 ( Table 7). The well-irrigation norm is 4755 m 3 /ha, and the annual amount of water used for well irrigation of farmland is 6.7 × 10 7 m 3 (Tables 2 and 8). Under a 75% irrigation probability, blocked canals caused the area of river-irrigated farmland to decrease by 11,764.3 ...Citations
... One reason for the inability to estimate the consumption of groundwater versus river water for irrigation is that farmland has not previously been classified into well-irrigated farmland (i.e., farmland that can be only irrigated with groundwater) and double-irrigated farmland.(i.e., farmland that can be irrigated with both canal water and groundwater). In a previous study, we designed a method to classify farmland into various categories, but the numbers of irrigation events that used canal water and groundwater could not be determined [13]. ...
... Therefore, croplands were classified into two categories: well-irrigated cropland and double-irrigated cropland (i.e., cropland that could be irrigated by both groundwater and canal/river water). The detailed method is described in a previous study [13]. ...
The Yellow River Water Allocation Management Method was put into place in 1998 to decrease the Yellow River water amount used by upstream areas and provide more water to downstream regions. Rainfall and Yellow River’s infiltration are the main groundwater supply in the downstream area of Yellow River. The groundwater table in the downstream area has continued to decrease since 1979, and the extracted groundwater for irrigation is the main reason for this. Whether the increased river water amount could improve the decreased groundwater level is uncertain. Therefore, we used remote sensing images, groundwater level observations, meteorological data, and unit mean irrigation rate to identify the irrigation events for river water and groundwater, estimate the annual river water irrigation amount and groundwater irrigation amount, and analyze the effects of river water allocation on the groundwater table. Our analysis showed that the area of double-irrigated farmland (farmland that could be irrigated by both groundwater and river water) tended to decrease, while well-irrigated farmland area (farmland that could only be irrigated by groundwater) remained unchanged during the study period. The number of annual irrigation events tended to increase, and the usage of river water remained consistent throughout this period. The increased number of well irrigation events caused annual groundwater usage for irrigation to increase. However, the usage of river water for irrigation remained stable. The increased usage of groundwater for irrigation led the groundwater table to continually decrease from 1998 to 2019. This indicates that there are shortcomings to the current water allocation policy, and that further improvements are needed to prevent continued decrease in groundwater levels.
... (i.e., farmland that can be irrigated with both canal water and groundwater). In a previous study, we designed a method to classify farmland into various categories, but the numbers of irrigation events that used canal water and groundwater could not be determined [13]. ...
... Therefore, croplands were classified into two categories: well-irrigated cropland and double-irrigated cropland (i.e., cropland that could be irrigated by both groundwater and canal/river water). The detailed method is described in a previous study [13]. ...
The Yellow River Water Allocation Management Method was put into place in 1998
to decrease the Yellow River water amount used by upstream areas and provide more water to downstream regions. Rainfall and Yellow River’s infiltration are the main groundwater supply in the downstream area of Yellow River. The groundwater table in the downstream area has continued to decrease since 1979, and the extracted groundwater for irrigation is the main reason for this. Whether the increased river water amount could improve the decreased groundwater level is uncertain. Therefore, we used remote sensing images, groundwater level observations, meteorological data, and unit mean irrigation rate to identify the irrigation events for river water and groundwater, estimate the annual river water irrigation amount and groundwater irrigation amount, and analyze the effects of river water allocation on the groundwater table. Our analysis showed that the area of double-irrigated farmland (farmland that could be irrigated by both groundwater and river water) tended to decrease, while well-irrigated farmland area (farmland that could only be irrigated by groundwater) remained unchanged during the study period. The number of annual irrigation events tended to increase, and the usage of river water remained consistent throughout this period. The increased number of well irrigation events caused annual groundwater usage for irrigation to increase.
However, the usage of river water for irrigation remained stable. The increased usage of groundwater for irrigation led the groundwater table to continually decrease from 1998 to 2019. This indicates that there are shortcomings to the current water allocation policy, and that further improvements are needed to prevent continued decrease in groundwater levels.
Keywords: groundwater level decrease; irrigation amount; irrigation events; water management policies
... Because of the incorrect irrigation water usage, farmers face a lack of efficiency or plant decays besides time and economic losses, and targeted planting cannot be achieved [5][6][7]. To prevent these losses, classification of the irrigation waters for intended purpose becomes valuable [8]. Irrigation waters are identified and classified basically according to the salinity and sodium contents [6]. ...
Türkiye, elverişli iklim koşullarına ve tarım için kullanılabilecek su kaynaklarına sahip bir ülkedir. Ülkedeki yüzey sularının çoğu sulama amaçlı kullanılabilir. Elektrik iletkenliği (EC), sulama suyunun tuzluluğunun bir ölçüsüdür, tuzluluk da doğrudan ppm cinsinden ölçülebilir. Yüksek tuzlu su, yüksek ozmotik basınç nedeniyle bitki köklerinin su beslemesini engellemekte, bu da sulama suyunun etkinliğini azaltmaktadır. Kalsiyum ve magnezyum miktarlarına göre sodyum miktarının bir ölçüsü olan Sodyum adsorpsiyon oranı (SAR), sulama suyunun kalitesinin bir göstergesidir. Sulama suyundaki yüksek SAR değerleri, infiltrasyon diye bilinen toprakta geçirimsizlik sorununa ve ürünün su alımında azalma oluşmasına yol açar. Bu çalışmada, Doğu Akdeniz Havzasından seçilen dört yüzey suyu, sulama amacıyla kullanılabilirliklerini değerlendirmek için seçilmiştir. Doğu Akdeniz Havzası, iklim koşulları nedeniyle verimli bir arazi olduğundan, havzanın sulama suyunun kalitesinin izlenmesi büyük önem taşımaktadır. Seçilen yüzey suyu kütleleri 2015 ile 2019 yılları arasında üç aylık aralıklarla analiz edilmiştir. Tuzluluk ve alkalinite sınıfları, iyi sulama suyu kalitesine karşılık gelen ve her tür bitkiyi sulamak için kullanılabilen C2-S1 olarak bulunmuştur.
