Impact of soil drought on sap flow and water status of evergreen trees in a tropical monsoon forest in northern Thailand [An article from: Forest Ecology and Management]

This digital document is a journal article from Forest Ecology and Management, published by Elsevier in 2007. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
Hill evergreen forest is the dominant vegetation type in northern Thailand. In this region, there is higher atmospheric evaporative demand and lower soil moisture during the 5- to 7-month dry season than in the rainy season under influences from Asian monsoons. In an earlier study we revealed that canopy-scale transpiration is actively maintained even during the latter part of the dry season in hill evergreen forest. However, the impact of soil drought on tree water use was not investigated. To clarify the ecohydrological processes at this site, we used individual tree-scale measurements during a 2-year period to base our examination of whether limited water use in individual trees is caused by soil drought in the latter part of the dry season. Sap flow and water potential measurements were conducted in four evergreen trees, two large emergent trees 29.8 and 25.4m high, and two smaller understory trees 4.8 and 1.4m high. The amount of rainfall preceding the late dry season of 2004 was significantly less than that preceding the late dry season of 2003. Although a distinct decrease in sap-flow velocities in individual trees due to soil water stress was not found in the late dry season of 2003, it did become comparatively apparent in the late dry season of 2004; ranging from 10 to 40% for a given atmospheric evaporative demand. Furthermore, the reductions in sap-flow velocities and predawn stem-water potential were most significant in the smallest tree. The recovery of sap-flow velocities and water potential in the smallest tree after irrigation confirmed that the reductions in sap-flow velocity and predawn stem-water potential in the smallest tree were caused by soil drought. These results suggest that shallower roots could be reason for the significant decrease in water use in the smallest trees. The deeper roots of larger trees could be the reason for the reduced impact of soil drought on water use in larger trees, and canopy-scale transpiration might be maintained by larger trees, even in an unusually severe drought. These possibilities provide a new insight for management of evergreen forests under Asian monsoon influences.

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The 2011 Import and Export Market for Vegetable Saps and Extracts in Thailand

On the demand side, exporters and strategic planners focusing on vegetable saps and extracts in Thailand face a number of questions. Which countries are supplying vegetable saps and extracts to Thailand? How important is Thailand compared to others in terms of the entire global and regional market? How much do the imports of vegetable saps and extracts vary from one country of origin to another in Thailand? On the supply side, Thailand also exports vegetable saps and extracts. Which countries receive the most exports from Thailand? How are these exports concentrated across buyers? What is the value of these exports and which countries are the largest buyers?

This report was created for strategic planners, international marketing executives and import/export managers who are concerned with the market for vegetable saps and extracts in Thailand. With the globalization of this market, managers can no longer be contented with a local view. Nor can managers be contented with out-of-date statistics which appear several years after the fact. I have developed a methodology, based on macroeconomic and trade models, to estimate the market for vegetable saps and extracts for those countries serving Thailand via exports, or supplying from Thailand via imports. It does so for the current year based on a variety of key historical indicators and econometric models.

In what follows, Chapter 2 begins by summarizing where Thailand fits into the world market for imported and exported vegetable saps and extracts. The total level of imports and exports on a worldwide basis, and those for Thailand in particular, is estimated using a model which aggregates across over 150 key country markets and projects these to the current year. From there, each country represents a percent of the world market. This market is served from a number of competitive countries of origin. Based on both demand- and supply-side dynamics, market shares by country of

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The 2009 Import and Export Market for Vegetable Saps and Extracts in Thailand

On the demand side, exporters and strategic planners focusing on vegetable saps and extracts in Thailand face a number of questions. Which countries are supplying vegetable saps and extracts to Thailand? How important is Thailand compared to others in terms of the entire global and regional market? How much do the imports of vegetable saps and extracts vary from one country of origin to another in Thailand? On the supply side, Thailand also exports vegetable saps and extracts. Which countries receive the most exports from Thailand? How are these exports concentrated across buyers? What is the value of these exports and which countries are the largest buyers?

This report was created for strategic planners, international marketing executives and import/export managers who are concerned with the market for vegetable saps and extracts in Thailand. With the globalization of this market, managers can no longer be contented with a local view. Nor can managers be contented with out-of-date statistics which appear several years after the fact. I have developed a methodology, based on macroeconomic and trade models, to estimate the market for vegetable saps and extracts for those countries serving Thailand via exports, or supplying from Thailand via imports. It does so for the current year based on a variety of key historical indicators and econometric models.

In what follows, Chapter 2 begins by summarizing where Thailand fits into the world market for imported and exported vegetable saps and extracts. The total level of imports and exports on a worldwide basis, and those for Thailand in particular, is estimated using a model which aggregates across over 150 key country markets and projects these to the current year. From there, each country represents a percent of the world market. This market is served from a number of competitive countries of origin. Based on both demand- and supply-side dynamics, market shares by country of

Read More