Teja Tscharntke – författare

The multitrophic level approach to ecology addresses the complexity of food webs much more realistically than the traditional focus on simple systems and interactions. Only in the last few decades have ecologists become interested in the nature of more complex systems including tritrophic interactions between plants, herbivores and natural enemies. Plants may directly influence the behaviour of their herbivores' natural enemies, ecological interactions between two species are often indirectly mediated by a third species, landscape structure directly affects local tritrophic interactions and below-ground food webs are vital to above-ground organisms. The relative importance of top-down effects (control by predators) and bottom-up effects (control by resources) must also be determined. These interactions are explored in this exciting volume by expert researchers from a variety of ecological fields. This book provides a much-needed synthesis of multitrophic level interactions and serves as a guide for future research for ecologists of all descriptions.

The multitrophic level approach to ecology addresses the complexity of food webs much more realistically than the traditional focus on simple systems and interactions. Only in the last few decades have ecologists become interested in the nature of more complex systems including tritrophic interactions between plants, herbivores and natural enemies. Plants may directly influence the behaviour of their herbivores' natural enemies, ecological interactions between two species are often indirectly mediated by a third species, landscape structure directly affects local tritrophic interactions and below-ground food webs are vital to above-ground organisms. The relative importance of top-down effects (control by predators) and bottom-up effects (control by resources) must also be determined. These interactions are explored in this exciting volume by expert researchers from a variety of ecological fields. This book provides a much-needed synthesis of multitrophic level interactions and serves as a guide for future research for ecologists of all descriptions.

Tropical rainforests disappear at an alarming rate causing unprecedented losses in biodiversity and ecosystem services. The stability of rainforest margins has an ecological and socio-economic dimension, and understanding the multidisciplinary nature of land-use changes in tropical rainforest margins is the key to identifying development objectives such as mitigation of biodiversity loss and poverty reduction. The chapters in this book cover a broad range of topical research areas, from impacts of different forest-use intensities, sustainable management of agroforestry to integrated land-use concepts.

not only for land use systems that depend on the regular supply of rain or irrigation water but also for the future development of natural rainforests as drought stress has been shown to a?ect tree growth and species composition in old-growth forests (Wright 1991, Walsh and Newbery 1999, Engelbrecht et al. 2007). A drought experiment conducted in a cacao agroforestry plantation showed that this plantation was surprisingly resilient to an induced drought of more than a year (Schwendenmann et al. 2009). However, droughts can have a strong impact on household incomes from agriculture, they strongly a?ect the vulnerability to poverty and thus have to be analyzed as important exogenous shocks to households, forcing them to adjust their behaviour and develop strategies to cope with these problems. The stability of rainforest margins is a critical factor in the protection of tropical rainforests (Tscharntke et al. 2007). At present, however, rainf- est margins in many parts of the tropics are far from stable, both in soc- economic and in ecological terms. For example, protected areas may attract, rather than repel, human settlement, which may be due to international donor investment in national conservation programs (Wittemeyer et al. 2008). An alternative hypothesis is that protected areas might be compromised if leakage takes place, that is, if impacts that would take place inside the restricted area are displaced to a nearby, undisturbed area (Ewers and Rodrigues 2008).

Tropical rainforests are disappearing at an alarming rate, causing unprecedented losses in biodiversity and ecosystem services. This book contributes to an improved understanding of the processes that have destabilizing effects on ecological and socio-economic systems of tropical rain forest margins, as well as striving to integrate environmental, technological and socio-economic issues in their solution.