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โครงการหนังสืออิเล็กทรอนิกส์ด้านการเกษตร เฉลิมพระเกียรติพระบาทสมเด็จพระเจ้าอยู่หัว

Abstract

Increasing demand of agriculture with rising population and consequent increased

demand of food and more recently, the proliferation of biomass-based energy promises to
increase stress on water, an already scarce resource. This is of particular concern to

Thailand which has a large agricultural base both for food for local consumption and export
as well as for feed and fuel (bio-fuels). The study has applied the water footprint concept to

evaluate the consumptive water use for 10 major food, feed, fuel crops in Thailand e.g. rice,
cassava, sugarcane, oil palm, soybean and others. In addition, the water stress index (WSI)

of 25 major watersheds of Thailand has also been evaluated to indicate the competitive
pressure on water resources availability in a specific region. The water stress map classified

by WSI criteria set in the study pointed out that the watershed that has the highest WSI is
Mun followed by Chi, Chaopraya, and Thachin, respectively. While, there is a large variation

of WF results of crops grown in different provinces due to several factors.
As the promotion of bioethanol in Thailand raises concerns on the possibility of

increased stress on water, particularly vis-à-vis competition for food, feed and fuel. The study
has applied the WF assessment and the WSI developed for 25 major watersheds of Thailand

to determine the water deprivation impact potentials from bioethanol production in Thailand
as a case study. The results show that the water footprint of bioethanol in Thailand varies

between 1,396-3,105 L water/L ethanol with cassava ethanol having the highest WF followed
by molasses and sugarcane ethanol. Nevertheless, in terms of blue water consumption,

important for water resources management, molasses is the highest at around 699-1,220 L/L
ethanol, followed by sugarcane and cassava at 450-859 and 449-566 L/L ethanol,

respectively. To satisfy the AEDP’s target of bioethanol production in 2021, around 1,625
3
million m of irrigation water/year will be additionally required. The Mun and Chi watersheds
in Northeast Thailand would have a significant increase in irrigation water demand that could
potentially lead to pressures on water stress and competition with other users.

In summary, the WF assessment and the WSI index can provide the useful
information for identification of the potential areas of water stress due to the expansion of

agricultural activities and for determining the measures for improving water resource planning
and management for sustainable food, feed, and fuel crops production in the future. Several

measures are also recommended in the report to enhance the water efficiency and water
resource management for agricultural sector in Thailand and to mitigate the water completion

for food, feed, fuel production in the future.