CO2 Impacts Tropical Forest Resistance to Climate Change

by Leta Ames

It is well known that fire can play a crucial role in the reproduction and development of plant populations. The availability of water and CO2 also impact plant growth, especially of larger species. It is believed that the interactions of climate, fire, and CO2 greatly influence the shift between savanna and tropical forest ecosystems and their permanence thereafter. Previous research has relied on data collected from intact tropical forests, but although useful, these data only provide a snapshot of the impact of CO2, fire, and climate on these ecosystems. To gain a better understanding of what factors influence tropical ecosystems Shanahan et al. (2016) used the concentrations of carbon and hydrogen stable isotopes from sedimentary leaf wax n-alkanes (δ13Cwax and δDwax) and the frequency of charcoal layers from sediment obtained from Lake Bosumtwi in Ghana to construct a history of changes in vegetation and hydrology, as well as to estimate the annual fire frequency. Continue reading

Ecological Networks are more Sensitive to Plant than to Animal Extinction under Climate Change

by Leta Ames

There is a growing need for climate change models that can accurately represent not only the effects on individual species, but also the interactions and compounding effects within ecosystems. These interactions between species form different “mutualistic networks”. Schleuning et al. (2016) modeled the impact of individual species’ responses to climate change in plant-animal mutualistic networks. Specifically, climatic tolerance of 295 plant species, in eight pollinator networks and five seed-disperser networks in unique areas of central Europe were used to understand the relationship between sensitivity to climate change, climatic niche breadth, and biotic specializations. Continue reading