Global issues
Bioeconomic sustainability of cellulosic biofuel production
The use of marginal land (ML) for lignocellulosic biofuel production is examined for system stability, resilience, and eco-social sustainability. A North American prairie grass system and its industrialization for maximum biomass production using biotechnology and agro-technical inputs is the focus of the analysis. Demographic models of ML biomass production and ethanol farmer/producers are used to examine the stability properties of the ML system. A bio-economic model that maximizes the utility of consumption having the dynamics of MLs and the farmer/producers as dynamic constraints is used to examine the effects of increased conversion efficiency, input costs, risk, and levels of base resources and inputs on the competitive and societal solutions for biomass production. We posit ML abandonment after biofuel production ceases could lead to permanent land degradation below initial levels that prohibit the establishment of the original flora and fauna.Gutierrez A.P., Ponti L., 2009. Bio-economic sustainability of cellulosic biofuel production on marginal lands. Bulletin of Science Technology and Society, 29: 213-225.http://dx.doi.org/10.1177/0270467609333729
European perspective on biofuels
In light of the recently developed European Union (EU) Biofuels Strategy, we reviewed the literature to examine: (1) the coherency of biofuel production with the EU non-industrial vision of agriculture, and (2) given its insufficient landbase, the implications of a proposed bio-energy pact to grow biofuel crops in the developing world to meet EU biofuel demands. The EU acknowledged that the use of food crops for biofuel production was based on wrong assumptions concerning climate change mitigation, and its support has now shifted to second generation nonfood crops. The bio-energy pact entails: (1) biofuel crops production in developing countries, especially Africa that in the absence of environmental and social regulations may lead to ethical trade-offs in land use (food vs. fuel); and (2) the use of transgenic technology that conflicts with the EU’s own vision of sustainable agriculture.Ponti L., Gutierrez A.P., 2009. Overview on biofuels from a European perspective. Bulletin of Science Technology and Society, 29: 493–504.http://dx.doi.org/10.1177/0270467609349048
Potential distribution of light brown apple moth
The highly polyphagous light brown apple moth (LBAM) (Epiphyas postvittana (Walk.): Tortricidae) is indigenous to Australia and was first found in California in 2006. It is currently found in 15 coastal counties in California, but nowhere has it reached outbreak status. The USDA projects the geographic range of LBAM will include much of Arizona and California and the southern half of the U.S., which together with economic estimates of potential crop losses have been used as the rationale for an eradication program in California. We report a temperature-driven demographic model to predict the likely distribution and relative abundance of LBAM using the detailed biology reported by W. Danthanarayana and colleagues, and climate data from 151 locations in California and Arizona for the period 1995 to 2006. The predictions of our model suggest that the near coastal regions of California are most favorable for LBAM, the northern Central Valley of California being less favorable, and the desert regions of Arizona and California being unfavorable.Gutierrez A.P., Mills N.J., Ponti L., 2010. Limits to the potential distribution of light brown apple moth in Arizona-California based on climate suitability and host plant availability. Biological Invasions, DOI 10.1007/s10530-010-9725-8.
http://dx.doi.org/10.1007/s10530-010-9725-8
Invasive potential of medfly in California and Italy
Since being detected in California in 1975, the polyphagous tropical Mediterranean fruit fly (Ceratitis capitata Weid. (medfly)) has been the subject of a large-scale eradication campaign in the absence of sound knowledge of its invasive potential. We use a weather-driv en physiologically-based demographic system model (CASAS) embedded in a GIS based on GRASS to examine medfly’s potential distribution across Arizona-Calif ornia (AZ-CA), and Italy where its establishment is documented. AZ is unfavorable for medfly because of high summer temperatures, while much of CA, including many frost-free areas, is too cold during winter. Only the south near coastal region of CA is predicted to be potentially favorable for medfly, but in the absence of consistent measurable populations, we cannot say if medfly is established there. Medfly has been established in Italy for decades, and our model predicts a wide distribution in the southern and western regions of the country. Gutierrez A.P., Ponti L., 2011. Assessing the invasive potential of the Mediterranean fruit fly in California and Italy. Biological Invasions, DOI 10.1007/s10530-011-9937-6.
http://dx.doi.org/10.1007/s10530-011-9937-6
Analysis of the glassy-winged sharpshooter system
The capacity to predict the geographic distribution and relative abundance of invasive species is pivotal to developing policy for eradication or control and management. An example is the glassy-winged sharpshooter Homalodisca vitripennis (Germar) (GWSS) in California which vectors the bacterial pathogen Xylella fastidiosa (Wells) that causes Pierce’s disease in grape and scorch-like diseases in other plants. A weather driven demographic model of grape, GWSS, its two parasitoids (Gonatocerus ashmeadi Girault and G. triguttatus Girault) and the pathogen was developed to show how the geographic distribution and abundance of GWSS as affected by weather and natural enemies in California can be easily assessed. The distribution of X. fastidiosa is limited to the warm inland areas of southern California. Biological control of GWSS further decreases the pathogen’s relative range. Two climate warming scenarios show that increasing temperatures will increase GWSS severity in the agriculturally rich central valley of California. The utility of holistic analyses for formulating control policy and tactics for invasive species is discussed.
Gutierrez A.P., Ponti L., Hoddle M., Almeida R.P.P., Irvin N.A., 2011. Geographic distribution and relative abundance of the invasive glassy-winged sharpshooter: effects of temperature and egg parasitoids. Environmental Entomology 40: 755-769.