Alterations in climate due to increasing atmospheric concentrations of carbon dioxide and other trace gases must be viewed with concern, if not alarm, because of the risk of adverse impacts on the availability and quality of water resources. Hydrologic changes may lead to alterations in pressure on food resources in many regions of the world. This paper explores the mechanisms by which food security - defined here as the ability of a region to produce or otherwise provide food without threatening the well-being of either the population or the existing political systems - could be affected by climate-induced changes in water resources. Shifts in the timing, magnitude, or location of major hydrologic phenomena, such as runoff, soil moisture, or monsoons, are discussed, together with the important vulnerabilities of agricultural productivity to changes in water availability. Some of the concomitant political and socioeconomic implications are also presented, with suggestions for ways to enhance the reliability of food resources dependent on uncertain water supplies.

The relation between dehydration mechanism and water activity of filefish muscle was investigated. Filefish muscle in the form of thin plate (5x10x0.4cm) was dried in a forced air dryer at 47.5 deg Centigrade. The moisture content and the water activity at which the second falling rate period started were not constant, because the drying rate of the first falling rate period was strongly dependent on the air humidity. The second falling rate period was again divided into two drying rate periods, the former and latter periods. The diffusion coefficient of water was 2.89x10 to the negative ten power m2/sec at 47.5 deg Centigrade. At this stage, the case-hardening continued until the water activity reduced to 0.7. The latter period of the second falling rate period started at the water activity of 0.45. The number of molecular layers was 4, and the diffusion coefficient of water during this stage was 4.38x10 to the 11th power m2/sec at 47.5 deg Centigrade

Environmental deterioration in ponds and costal waters has been a common evidence after each intensive shrimp culture due to the accumulation of organic wastes and occurrence of eutrophication processes. Mangrove is a wetland that potentially supports the natural food web in the estuary and coastal areas. The planting of mangroves in recycling shrimp farms would serve the purpose of developing sustainable shrimp farms by utilizing the enriched organic matters and nutrients thus enhancing the natural food web in the shrimp farms. However, mangrove trees in pond dikes tend to grow small and the roots may not be able to support the tree during pond erosion resulting in the mortality of the mangrove trees. Brackishwater weeds, which cover the soil in the pond dikes, could serve the function of the young mangrove trees.

At first glance, it appears that the region is well endowed with water resources. While accounting for only about 16 percent of the world's land surface, it receives 22 percent of its precipitation and produces 28 percent of its renewable water resources. However, the region is home to 53 percent of the world's population and its IRWR [internal renewable water resources] are only about half of the world's average. By and large, most countries in Asia (except for Singapore, Maldives and Republic of Korea) are still not considered water-stressed. However, even in countries with high level of per capita water availability, large segments of the population are beset with water scarcity as a result of the large variations in the spatial and temporal distributions of rainfall and stream flow. About 84 percent of the total water withdrawal of the region is for agriculture. Irrigation accounts for the bulk of water use in agriculture due to the large irrigation base and the fact that approximately half of the irrigated area is devoted to flooded rice production. Although still relatively small in most Asian countries, the industrial, municipal and environmental demands for water continue to increase at a rate twice that of population growth. The proportion of water available for agriculture is projected to decline to 62 percent worldwide and 73 percent in developing countries by 2020. Hence, the opportunities for expanding the irrigation base are limited. If food security is to be maintained, ways of increasing water productivity must be found. A host of interrelated issues must be addressed in the short-and-medium terms if a water crisis in the region is to be averted. Among others, these include: changing demand patterns, impact of climate change and watershed modifications on dependable water supply, low water productivity in agriculture,in adequate investments in water supply systems to meet future demands, a shift toward decentralized and privatized water service and market mechanisms, the need to reduce non-revenue water, sustaining and expanding the irrigation base, recycling wastewater for agriculture, access to water of the rural and urban poor, groundwater mining, the need to strengthen international collaboration for managing shared water resources, protection of freshwater ecosystems, and fostering a favorable environment for a comprehensive water resources policy and program frameworks. The specific issues in irrigation that are more pressing were discussed. Suggestions on how to address these issues were presented. Two very significant changes in irrigation development policy and strategy in many developing countries of Asia were discussed. First is the shift from large, gravity irrigation systems towards small privatized farmer-controlled irrigation systems such as shallow tubewells, low-lift pumps, farm reservoirs and diversion dams. Second is the dramatic shift from the virtual monopoly of the central role of national government towards greater participation of other players such as WUAs [water users association], NGOs [non governmental organizations], and local government units. The public sector activities are now focused on improving the management of water at the main system level and adopting new policies aimed at creating incentives for WUAs or cooperatives to take over the O and M [operation and management] of the rest of the irrigation facilities.

One dimensional unsteady heat conduction was studied on soybean curd as a water-protein-fat food system. This heterogeneous soybean curd could be treated as homogeneous material for the unsteady heat conduction by "effective" thermal diffusivity. Measurements were made with an apparatus designed and constructed by the author and also made with ice to establish the reliability, the reproducibility and the accuracy of the apparatus. The effective thermal diffusivity of soybean curd was substantially dependent on the fraction of protein and fat as well as water