C2 - Diversity and spatial distribution of herbaceous and woody plant assemblages in relation to natural and anthropogenic factors

Abstract
With the general aim of documenting and interpreting the spatial variability of plant diversity and composition in relation to environmental factors (elevation, soil, topography, climate) and land use in the study region, we will
(a) gather tree data across the elevational gradient from 200 m to 2500 m as a basis for forest biodiversity and structure modelling in the scope of focus 1,
(b) inventory tree diversity in the plots of foci 2 and 3, at the Bariri tower site, and around Lake Lindu as essential baseground data for other subprojects,
(c) study the terrestrial herb vegetation in the framework of foci 1 and 2, and
(d) study the taxonomy, distribution and ecology of rattans in the study region.

Summary
The factors determining the spatial variability of plant assemblage diversity and composition in relation to environmental factors (elevation, soils, topography, climate) and land use in the tropics in general, and in the study region in particular, are still poorly understood. Even less is known about the functional role of this diversity. Our research will focus on three plant groups, namely (a) trees as the basic structural components of forests and were the main focus of our research in phases 1 and 2, (b) herbs that are often fairly sparsely distributed in the dark interior of tropical forests, but have recently received considerable attention in efforts to classify tropical forest vegetation and to relate its variation to environmental factors, and that also play a vital role in agricultural systems where they can either be weeds or fulfil important ecological functions, and (c) rattan palms as the most important forest product in the study region (besides timber) that is extracted and exported in large quantities: it is estimated that ca. 40% of the World export of rattan comes from Lore Lindu NP and the surrounding areas. Our research will include four complementary components that build and expand on our research in phases 1 and 2, and is firmly imbedded in foci 1, 2 and 3: (1a) A specialist team will rapidly inventory the trees in the plots of foci 2 and 3, at the Bariri tower site, and around Lake Lindu using the standard field methods employed in phases 1 and 2, as indispensable baseground data for other projects. (1b) Our Indonesian counterpart R. Pitopang will gather tree data with the same method across the elevational gradient from 200 m to 2500 m as a basis for forest biodiversity, structure, and above-ground biomass modelling in the scope of focus 1. (2) The German PhD student will study the terrestrial herb vegetation, partly in the context of foci 1 and 2 in several hundred plots of 5 x 5 m each. Plots will be established at all study sites of foci 2 and 3, at the Bariri tower site and at another site around Toro (in collaboration with B6), and at all sites previously sampled in phases 1 and 2 for their tree diversity (in order to establish a compatible data base of herbs and trees in the entire study region). In each study plot, canopy closure and photosynthetic active radiation (PAR) will be measured and superficial soil samples will be taken and analyzed for pH, C-contents, N-contents, P-contents, and cation exchange capacity. At the study sites of focus 2, five plots of 5 x 5 m each will be established at each site and will be sampled and digitally photographed at the beginning of the experiments and after 6, 12, 18, and 24 months. (3) The Indonesian PhD student in collaboration with a German research assistant will study the taxonomy, distribution and ecology of rattans of the study region using traditional morphological and modern DNA and morphometric methods as a basis for population modelling and monitoring as well as economic asessments. In combination, our research is aimed at the production of about 10 key publications, involving especially interactions will the functional foci of STORMA (foci 2 and 3), the socioeconomic components of STORMA, and of the modelling approaches.