Effects of biodiversity enrichment in oil palm monocultures on pollinator diversity

Introduction

The proposed Master thesis will be conducted within subproject B09 (Tscharntke/Grass) "Aboveground patterns of biodiversity and associatedecosystem processes across tropical rainforest transformations" within CRC 990. I will study effects of biodiversity enrichment in oil palm monoculture on insect biodiversity, plant-pollinator interactions and pathogens. The overall aim of this study is to discern the potentials of different degrees of diversification and plot size on selected ecosystem functions.

Location
The study is located in the 56 B11 oil palm enrichment experiment.

Methodology
Generally, the enrichment plots will be described in their development (height and size of the trees, plants) first. Biodiversity data are collected using trap methods (sweep-netting, pan traps) on all plots of the B11 enrichment experiment. I will test different trap methods for measuring the insect biodiversity established four years after enrichment begun. Therefore I will do sweep netting and pan trapping within all 56 enrichment plots. The trap methods will be repeated several times during the study course. The collected insects will be identified afterwards. In addition, direct observation of plant-pollinator interactions will be done (focusing on flowering weeds within the enrichment plots). Finally, depending on the height and the possibility to reach the leaves of the adjacent oil palms, I will investigate the pathogen and herbivore pressure, and how this is modified by enrichment diversity.

Expected Results
I will establish baseline biodiversity data for the enrichment plots of the CRC 990. The effects of different degrees of diversification and the influence of plot size on the diversity and ecosystem services of beneficial insects will be identified.