Seriously. You're claiming that rising CO2 *might* cause extinctions *someday* and that to avoid it, we have to quit emitting CO2. Earth to futurecurrents! The replacement for fossil fuels are biofuels. And biofuels require land to grow them on. Of course this is a modification of the environment.
Before the ethanol industry grew large, the environmentalists were all about mandating ethanol in the gasoline supply. It was only after they saw the consequences (thousands of square miles of factory farms) that they got on the bandwagon against ethanol. As more biofuels are brought under cultivation, the same thing will happen again.
Here are some links. You should note that these are from people who believe the alarmist paradigm on global warming:
Is energy cropping in Europe compatible with biodiversity?
Pedroli, Elbersen, Frederiksen, Grandin,Heikkila, Krogh, Izakovicova, Johansen, Meiresonne and Spijker
Biomass and Bioenergy, Volume 55, August 2013, pp 73-86
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We conclude that increased demand for biomass for bioenergy purposes may lead to a continued conversion of valuable habitats into productive lands and to intensification, which both have negative effects on biodiversity.
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http://www.sciencedirect.com/science/article/pii/S0961953412003947
The impacts of biofuel production on biodiversity: A review of the current literature
United Nations Environment Programme World Conservation Monitoring Centre (UNEP-WCMD) is the biodiversity assessment and policy implementation arm of the United Nations Environment Programme (UNEP), the world's foremost intergovernmental environmental organization.
Campbell and Doswald (2009)
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The biodiversity impact of biofuels will depend on the biofuel crop and the previous land use. Biofuels can be beneficial to biodiversity when appropriate crops are grown in suitable areas. Furthermore, if they contribute to climate change mitigation, they have the potential to be indirectly beneficial to biodiversity as a whole. However, biofuels have already been shown to negatively impact biodiversity when direct conversion of natural ecosystems or indirect land conversion of non-degraded land occurs. The expansion of biofuel production in the tropics has resulted in the loss of tropical forest and wetlands, and in temperate regions biofuel production has encroached into set-aside lands. Biofuel feedstock plantations (particularly oil palm and maize plantations), have been shown to support far lower levels if biodiversity than natural ecosystems, and can cause soil erosion and the pollution of watercourses. How a feedstock plantation is managed influences the level of biodiversity impacts. Well managed plantations can in some instances prove beneficial to biodiversity especially if these are on degraded or marginal lands.
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https://www.cbd.int/agriculture/2011-121/UNEP-WCMC3-sep11-en.pdf
Biofuels and Biodiversity
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Biofuels have the potential to affect all of the major drivers of biodiversity loss identified in Global Biodiversity Outlook 3 (SCBD 2010): habitat loss and degradation; climate change; excessive nutrient load and other forms of pollution; over-exploitation and unsustainable use; and invasive alien species. Furthermore, although biofuels are partly intended to mitigate climate change by reducing greenhouse gas (GHG) emissions, many biofuels used today emit as much, or more, GHGs as fossil fuels or offer very limited savings, when taking into account their entire lifecycle, and when indirect land-use change is taken into consideration (e.g., Fargione et al. 2008; Searchinger et al . 2008).
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Secretariat of the Convention on Biological Diversity, CBD Technical Series No. 65 (2012)
https://www.cbd.int/doc/publications/cbd-ts-65-en.pdf
Biofuels and biodiversity
Wiens, Fargionne and Hill
Ecological Applications, Ecology Society of America, Volume 21, Issue 4, 1085-1095 (June 2011)
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Current biofuel production occurs largely on croplands that have long been in agricultural production. The additional land area required for future biofuels production can be met in part by reclaiming reserve or abandoned croplands and by extending cropping into lands formerly deemed marginal for agriculture. In the United States, many such marginal lands have been enrolled in the Conservation Reserve Program (CRP), providing important habitat for grassland species. The demand for corn ethanol has changed agricultural commodity economics dramatically, already contributing to loss of CRP lands as contracts expire and lands are returned to agricultural production.
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http://www.esajournals.org/doi/abs/10.1890/09-0673.1
http://www.esajournals.org/doi/abs/10.1890/09-0673.1
Also of interest:
Greenhouse Gas Emissions From Indirect Land Use Change
Michael O'Hare, Goldman School of Public Policy, University of California, Berkeley
CARB LCFS Working Group 3, (2008)
http://www.arb.ca.gov/fuels/lcfs/011708uCBLuCB&W.pdf
