the GlobalChangeBiology blog

The distribution and abundance of species that cause economic loss (i.e., pests) in crops, forests or livestock depends on many biotic and abiotic factors that are thought difficult to separate and quantify on geographical and temporal scales. However, the weather-driven biology and dynamics of such species and of relevant interacting species in their food chain or web can be captured via mechanistic physiologically based demographic models (PBDMs) that can be implemented in the context of a geographic information system (GIS) to project their potential geographic distribution and relative abundance given observed or climate change scenarios of weather. PBDMs may include bottom-up effects of the host on pest dynamics and, if appropriate, the top-down action of natural enemies. When driven by weather, PBDMs predict the phenology, age structure and abundance dynamics at one or many locations enabling projecting the distribution of the interacting species across wide geographic areas. PBD

Agroecology: a viable agricultural path for a planet in crisis. It is now clear that humanity needs an alternative agricultural development paradigm, one that encourages more ecologically, biodiverse, resilient, sustainable and socially just forms of agriculture. The basis for this new systems are the myriad of ecologically based agricultural styles developed by over a billion smallholders, family farmers and indigenous people on hundreds of millions of small farms which currently produce most of the global agricultural output for domestic consumption largely without agrochemicals. Agroecology is this paradigm: a dialogue between traditional agricultural knowledge and modern agricultural science that uses ecological concepts and principles for designing and managing sustainable agroecosystems in which external inputs are replaced by natural processes such as natural soil fertility and biological control. This book explains why agroecology is the most robust food provisioning pathway fo