Download presentation
Presentation is loading. Please wait.
Published byMeghan Wilkins Modified over 9 years ago
1
Hay meadows: Biofuels for Biodiversity?
2
Maize (corn) as a biofuel Do the energetics balance?
3
Switchgrass has advantages over maize Locally adapted High genetic variation High water use efficiency High nitrogen use efficiency Perennial Low erosion
4
However, introducing a new monoculture may be a mistake. Problems with monocultures: Disease Unstable production Costly (energetics as well as money) No nitrogen-fixing legumes Nature abhors a monoculture Plowing means enhanced soil respiration, hence this is not a good solution for global warming
5
Switchgrass as the ‘next crop’ A California biotech company Ceres is genetically modifying switchgrass with genes from Arabidopsis to maximize yield. “You could turn Oklahoma into an OPEC member by converting all its farmland to switch grass”, said Richard W. Hamilton, the Ceres chief executive. –NY Times, 8 September 2006 Productivity is measured in yield – not the most energetically relevant measure. Wild switchgrass is everywhere in much of North America. Keeping transgenes from crossing with native switchgrass will prove impossible.
6
Hay meadows in Oklahoma
8
Abandonment of grasslands Vast acreages of hay meadows in the southern Great Plains are being abandoned, resulting in degraded systems of low value.
9
Eastern red cedar (Juniperus virginiana) is the main species invading unmanaged grasslands Cedar pollen causes severe allergy problems
10
Cedars represent an extreme fire danger problem
11
Cedars also: Alter hydrology Reduce diversity Increase erosion Reduce grassland bird populations (including threatened species) (however, cedars have uses – and there are genuine old-growth cedar stands in Oklahoma)
12
Biodiversity and biomass removal in grasslands
13
Many grasslands developed under a regime of biomass removal
15
Laeletu wooded meadow, Estonia Mowing is a frequently used management tool to enhance biodiversity worldwide In many cases, the cuttings are considered waste. Why not use them?
16
Mowing experiment, western Payne County Established 1996
17
Year of Sampling Mean species richness 19971998199920042005 5 10 15 20 25 30 35 Mowing frequency Control Single Double Triple
18
Will hay meadows, with complex species mixtures, work as biofuels? Probably, using gasification techniques.
19
Biofuels may make control of exotic species such as Johnsongrass or sericea cost-effective.
20
Multi-use systems are possible: biofuels are potentially compatible with livestock, honey, wildlife (game and nongame), conservation, windfarms
21
Numerous areas are subject to Nitrogen pollution Why not take advantage of this, and harvest the enhanced productivity?
22
Yield / acre: probably lower than other proposed biofuels such as switchgrass Yield / cost, Yield / water, yield / Nitrogen: probably higher than other proposed biofuels Benefits / cost: definitely much higher than other proposed biofuels Productivity of haymeadows
23
Other Environmental and Social Concerns with biofuels: Competes with food production Clearing of Amazon or other pristine areas Encouraging invasive species Transportation of fuels These are minimal issues with native hay meadows
24
Basic and theoretical ecology can benefit from interest in grasslands as biofuels. Note that geology, hydrology, physics and chemistry have all experienced major advances because of energy.
25
Conclusions: an equation A need to decrease dependence of fossil fuels for environmental and geopolitical stability + abandoned grasslands leading to environmental, health, and public safety problems + serious concerns about biofuel crops = Let us use our grasslands as a source of biofuels, for a sustainable economy and environment
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.