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โครงการหนังสืออิเล็กทรอนิกส์ด้านการเกษตร เฉลิมพระเกียรติพระบาทสมเด็จพระเจ้าอยู่หัว

Water deprivation impact potentials
3
Related (m eq./L ethanol)
watersheds Provinces Cassava Sugarcane Molasses

ethanol ethanol ethanol

Chi Kalasin, Khon Kaen, Chaiyaphum, 267-320 2,051
Nongbualumphu
Chao Phraya Nakhonsawan, Lopburi, 266 2,389

Ayutthaya

Thachin Nakhonpathom, Suphanburi 814
Bang Pakong Chachoengsao 8 1,218
East Coast Gulf Chonburi, Rayong 5-8 1,337

Khong Mukdahan, Udon Thani 6 1,147

Mae Klong Kanchanaburi, Ratchaburi 7-18 1,711
Pasak Phetchabun, Saraburi 1,885
Ping Kamphaengphet 8 1,806

Prachinburi Prachinburi, Sa Kaeo 6-7 2,051

Sakae Krang Uthai Thani 18 2,389
Salawin Tak 6 814

Nevertheless, it must be noted that the consumptive water use for bioethanol feedstocks

shown in Tables 8.2 and 8.3 are the theoretical water consumption which will result in the
overestimation for the cultivations that are subject to deficit irrigation (Pfister et al., 2009). This is

especially for the cassava and sugarcane in Thailand which are predominantly rainfed crops.

However, to estimate the irrigation water consumed by field crops like sugarcane and cassava in
reality is difficult as it depends on not only whether the plantation areas are located in the irrigation
areas, but also depends on how much the irrigation water available in each year depending on the

climatic variables. Anyway, for the rough estimation of irrigation water actually used by sugarcane

and cassava, the study refers to the water resources management plan for agricultural plantation in
irrigated areas during dry season of year 2011/2012 (RID, 2012b), the report shows that there are
around 0.22 M.ha of total field crops planted areas that will be able to receive the irrigation water

from RID and around 0.16 M.ha is the sugarcane planted areas. This irrigated sugarcane

plantation areas will account for only 13% of the total sugarcane planted areas in Thailand which is
about 1.24 M.ha. Based on the average yields of sugarcane which is around 72 ton/ha, the actual
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blue water footprint of sugarcane in Thailand would be only 5 m /ton sugarcane which is quite
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different from the theoretical blue water value of 41 m /ton sugarcane shown in Figure 8.4. This
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