@article {Holdo2009DiseaseMediated,
	title = {A Disease-Mediated Trophic Cascade in the Serengeti and its Implications for Ecosystem C},
	journal = {PLoS Biol},
	volume = {7},
	number = {9},
	year = {2009},
	month = {September},
	pages = {e1000210+},
	publisher = {Public Library of Science},
	abstract = {Tree cover is a fundamental structural characteristic and driver of ecosystem processes in terrestrial ecosystems, and trees are a major global carbon (C) sink. Fire and herbivores have been hypothesized to play dominant roles in regulating trees in African savannas, but the evidence for this is conflicting. Moving up a trophic scale, the factors that regulate fire occurrence and herbivores, such as disease and predation, are poorly understood for any given ecosystem. We used a Bayesian state-space model to show that the wildebeest population irruption that followed disease (rinderpest) eradication in the Serengeti ecosystem of East Africa led to a widespread reduction in the extent of fire and an ongoing recovery of the tree population. This supports the hypothesis that disease has played a key role in the regulation of this ecosystem. We then link our state-space model with theoretical and empirical results quantifying the effects of grazing and fire on soil carbon to predict that this cascade may have led to important shifts in the size of pools of C stored in soil and biomass. Our results suggest that the dynamics of herbivores and fire are tightly coupled at landscape scales, that fire exerts clear top-down effects on tree density, and that disease outbreaks in dominant herbivores can lead to complex trophic cascades in savanna ecosystems. We propose that the long-term status of the Serengeti and other intensely grazed savannas as sources or sinks for C may be fundamentally linked to the control of disease outbreaks and poaching.},
	keywords = {climate-change, co2, fire, grazing, vegetation},
	doi = {10.1371/journal.pbio.1000210},
	url = {http://dx.doi.org/10.1371/journal.pbio.1000210},
	author = {Holdo, Ricardo M. and Sinclair, Anthony R. E. and Dobson, Andrew P. and Metzger, Kristine L. and Bolker, Benjamin M. and Ritchie, Mark E. and Holt, Robert D.}
}
@article {LeQuere2009Trends,
	title = {Trends in the sources and sinks of carbon dioxide},
	journal = {Nature Geosci},
	volume = {2},
	number = {12},
	year = {2009},
	month = {November},
	pages = {831{\textendash}836},
	publisher = {Nature Publishing Group},
	abstract = {Efforts to control climate change require the stabilization of atmospheric CO2 concentrations. This can only be achieved through a drastic reduction of global CO2 emissions. Yet fossil fuel emissions increased by 29\% between 2000 and 2008, in conjunction with increased contributions from emerging economies, from the production and international trade of goods and services, and from the use of coal as a fuel source. In contrast, emissions from land-use changes were nearly constant. Between 1959 and 2008, 43\% of each year{\textquoteright}s CO2 emissions remained in the atmosphere on average; the rest was absorbed by carbon sinks on land and in the oceans. In the past 50 years, the fraction of CO2 emissions that remains in the atmosphere each year has likely increased, from about 40\% to 45\%, and models suggest that this trend was caused by a decrease in the uptake of CO2 by the carbon sinks in response to climate change and variability. Changes in the CO2 sinks are highly uncertain, but they could have a significant influence on future atmospheric CO2 levels. It is therefore crucial to reduce the uncertainties.},
	keywords = {climate, climate-change, co2},
	issn = {1752-0894},
	doi = {10.1038/ngeo689},
	url = {http://dx.doi.org/10.1038/ngeo689},
	author = {Le Quere, Corinne and Raupach, Michael R. and Canadell, Josep G. and Marland, Gregg}
}
@article {Rothman2001Global,
	title = {Global biodiversity and the ancient carbon cycle},
	journal = {Proceedings of the National Academy of Sciences of the United States of America},
	volume = {98},
	number = {8},
	year = {2001},
	month = {April},
	pages = {4305{\textendash}4310},
	abstract = {10.1073/pnas.071047798 Paleontological data for the diversity of marine animals and land plants are shown to correlate significantly with a concurrent measure of stable carbon isotope fractionation for approximately the last 400 million years. The correlations can be deduced from the assumption that increasing plant diversity led to increasing chemical weathering of rocks and therefore an increasing flux of carbon from the atmosphere to rocks, and nutrients from the continents to the oceans. The CO concentration dependence of photosynthetic carbon isotope fractionation then indicates that the diversification of land plants led to decreasing CO levels, while the diversification of marine animals derived from increasing nutrient availability. Under the explicit assumption that global biodiversity grows with global biomass, the conservation of carbon shows that the long-term fluctuations of CO levels were dominated by complementary changes in the biological and fluid reservoirs of carbon, while the much larger geological reservoir remained relatively constant in size. As a consequence, the paleontological record of biodiversity provides an indirect estimate of the fluctuations of ancient CO levels.},
	keywords = {biodiversity, carbon, co2, cycles, history, paleontology},
	doi = {10.1073/pnas.071047798},
	url = {http://dx.doi.org/10.1073/pnas.071047798},
	author = {Rothman, Daniel H.}
}
@article {Stickler2009Potential,
	title = {The potential ecological costs and cobenefits of REDD: a critical review and case study from the Amazon region},
	journal = {Global Change Biology},
	volume = {15},
	number = {12},
	year = {2009},
	month = {December},
	pages = {2803{\textendash}2824},
	address = {The Woods Hole Research Center, 149 Woods Hole Road, Falmouth, MA 02540, USA; Instituto de Pesquisa Ambiental da Amaznia, SHIN CA-5, Lote J2, Bloco J2, Brasilia-DF, CEP: 71503-505, Brazil; School of Natural Resources and Environment, Department of Geograp},
	abstract = {The United Nations climate treaty may soon include a mechanism for compensating tropical nations that succeed in reducing carbon emissions from deforestation and forest degradation, source of nearly one fifth of global carbon emissions. We review the potential for this mechanism [reducing emissions from deforestation and degradation (REDD)] to provoke ecological damages and promote ecological cobenefits. Nations could potentially participate in REDD by slowing clear-cutting of mature tropical forest, slowing or decreasing the impact of selective logging, promoting forest regeneration and restoration, and expanding tree plantations. REDD could also foster efforts to reduce the incidence of forest fire. Potential ecological costs include the accelerated loss (through displaced agricultural expansion) of low-biomass, high-conservation-value ecosystems, and substitution of low-biomass vegetation by monoculture tree plantations. These costs could be avoided through measures that protect low-biomass native ecosystems. Substantial ecological cobenefits should be conferred under most circumstances, and include the maintenance or restoration of (1) watershed functions, (2) local and regional climate regimes, (3) soils and biogeochemical processes, (4) water quality and aquatic habitat, and (5) terrestrial habitat. Some tools already being developed to monitor, report and verify (MRV) carbon emissions performance can also be used to measure other elements of ecosystem function, making development of MRV systems for ecological cobenefits a concrete possibility. Analysis of possible REDD program interventions in a large-scale Amazon landscape indicates that even modest flows of forest carbon funding can provide substantial cobenefits for aquatic ecosystems, but that the functional integrity of the landscape{\textquoteright}s myriad small watersheds would be best protected under a more even spatial distribution of forests. Because of its focus on an ecosystem service with global benefits, REDD could access a large pool of global stakeholders willing to pay to maintain carbon in forests, thereby providing a potential cascade of ecosystem services to local stakeholders who would otherwise be unable to afford them.},
	keywords = {amazon, biodiversity, co2, conservation, neotropics, redd, tropics},
	issn = {13541013},
	doi = {10.1111/j.1365-2486.2009.02109.x},
	url = {http://dx.doi.org/10.1111/j.1365-2486.2009.02109.x},
	author = {Stickler, Claudia M. and Nepstad, Daniel C. and Coe, Michael T. and McGRATH, David G. and Rodrigues, Hermann O. and Walker, Wayne S. and Soares-Filho, Britaldo S. and Davidson, Eric A.}
}
