Ulrich Schuler

Beyond the Horizons: Challenges and Prospects for Soil Science and Soil Care in Southeast Asia

The information available in relation to soils in Southeast Asia’s (SEA) mountainous regions is still limited, and so our research tried to rectify this situation in two key ways. The first approach was to gather soil information in order to help develop a soil database for parts of mountainous SEA. This approach also included two further issues important to soil knowledge in SEA, as reported in this study: Savanna regions with underlying limestone are unique to SEA, resulting in specific soil landscapes with soils of various degrees of weathering. Non-sustainable agriculture affects soil fertility in the uplands of SEA, in particular the frequent problem of soil erosion at hill slopes adversely affects both soil physical and chemical properties. The second approach was to develop and progress methods so as to improve soil research and soil analysis. These approaches included (1) gamma ray spectrometry to retrieve airborne and ground-based data on natural radioactive isotopes of potassium, thorium and uranium in soils, as proxies for rock and soil formation, (2) an inter-comparison of state of the art soil mapping approaches in an development oriented context, and (3) the evaluation of ethnic soil knowledge systems, those considered useful in the identification of local soil distribution patterns, though not suitable for transfer to a larger scale.

Variability of Soil Resources in Northern Thailand

There is still much of great value to discover about soil variability in the highlands of northern Thailand. Part of this chapter tries to review the state of knowledge of the highland soils and part presents results which have been produced within subproject B1 of SFB 564. This project follows a long-term strategy in which the variability of soil and water balance is researched beginning at a field scale and ending at a regional level. The same approach is also followed here.