Economic Potential of Biomass Based Fuels for Greenhouse Gas Emission Mitigation

Use of biofuels diminishes fossil fuelcombustion thereby also reducing net greenhousegas emissions. However, subsidies are neededto make agricultural biofuel productioneconomically feasible. To explore the economicpotential of biofuels in a greenhouse gasmitigation market, we incorporate data onproduction and biofuel processing for thedesignated energy crops switchgrass, hybridpoplar, and willow in an U.S. AgriculturalSector Model along with data on traditionalcrop-livestock production and processing, andafforestation of cropland. Net emissioncoefficients on all included agriculturalpractices are estimated through crop growthsimulation models or taken from the literature. Potential emission mitigation policies ormarkets are simulated via hypothetical carbonprices. At each carbon price level, theAgricultural Sector Model computes the newmarket equilibrium, revealing agriculturalcommodity prices, regionally specificproduction, input use, and welfare levels,environmental impacts, and adoption ofalternative management practices such asbiofuel production. Results indicate no rolefor biofuels below carbon prices of $40 perton of carbon equivalent. At these incentivelevels, emission reductions via reduced soiltillage and afforestation are more costefficient. For carbon prices above $70,biofuels dominate all other agriculturalmitigation strategies.     

湖南八大公山国家级自然保护区国家重点保护和珍稀濒危植物区系分析

从属和种的水平上分析了八大公山国家级自然保护区国家重点保护和珍稀濒危植物的区系成分特点。结果表明,该保护区共有国家重点保护和珍稀濒危植物31科44属53种。其中有国务院1999年8月4日批准公布的I级重点保护植物4科4属6种,II级重点保护植物18科23属29种;有《中国珍稀濒危保护植物名录》(1987)和《中国植物红皮书》所列的濒危植物2科2属2种,稀有植物14科15属16种,渐危植物15科19属20种。其区系具有由亚热带植物区系向温带植物区系过渡,但热带性质比较明显的特点,而且中国特有成份是该区系中非常重要的组成部分。     

Using quantitative influence diagrams to map natural resource managers’ mental models of invasive species management

Despite the significant effect that invasive species have on natural values, the number and extent of invasions continue to rise globally. At least three dominant reasons explain why policy development and implementation can fail: differences in managers’ mental models of invasive species management; cross-agency responsibility; and poor planning and management (i.e., planning–implementation gap). We used a case study of cross-agency management of gamba grass (Andropogon gayanus) in Australia to explore the differences in organizational staffs’ mental models of management. The gamba grass invasion in northern Australia is continuing to expand and associated effects are increasing; coordinated action across agencies is needed to manage the expansion. Our aim was to examine how staff would represent their mental models as a diagram that we could compare between individuals and groups. We used cognitive mapping techniques to elicit models of 15 individuals from across 5 organizations, represented as an influence diagram, which shows the interrelationships that define a system. We compiled the individual influence diagrams to create a team model of management that captures the common connections across participants’ diagrams. The team model revealed that education, science, legislation, enforcement and property management plans were perceived to be the most important management tools to control or eradicate gamba grass. The Weed Management Branch was perceived to have the most central role in gamba grass management, while other organizations were perceived to have specific roles according to their core business. Significant positive correlations (i.e., shared perceptions) were observed across half of the participants, indicating that the some participants have shared models that could be used as a starting point for discussing the team model, clarifying roles and responsibilities, and potentially building consensus around a shared model. Dominant opportunities for improvement identified by participants were better use of management tools, namely education and enforcement, better coordination and collaboration between agencies and increased resourcing. Our research demonstrates the value and validity of using influence diagrams to explore managers’ mental models and to create a team model that could serve as a starting point for improved cross-agency natural resource management.     

Carbon and energy prices under uncertainty: A theoretical analysis of fuel switching with heterogenous power plants

European power producers have a major influence on the EU ETS, given that both their CO₂ emissions and their EUA (European Union Allowance) allocations account for more than half of the total volumes of the scheme. Fuel switching is often considered as the main short-term abatement measure under the EU ETS. It consists in substituting combined cycle gas turbines (CCGTs) for hard-coal plants in power generation. Thereby coal plants run for shorter periods, and CO₂ emissions are reduced. This paper provides the first theoretical analysis of fuel switching, in a context where power plants involved are not equally efficient. We begin with a preliminary work using illustrative examples and sensitivity analyses, which enables us to observe how differences in the efficiency of power plants impact the cost of fuel switching, and how this is related to the level of switching effort. Based on this, we build a theoretical model taking into account the effect of differences in the efficiency of power plants involved in fuel switching. We also investigate the effect of the timing of fuel switching abatements, within the temporally defined environment of our dynamic model. Results demonstrate that the gas price and uncontrolled CO₂ emissions act together on the carbon price. We show that the influence of the gas price on the carbon price depends on the level of uncontrolled CO₂ emissions, due to heterogeneity of power plants that are used in the fuel switching process. Furthermore, we show that the time of occurrence of uncontrolled emissions matters so that shocks have a stronger impact when they occur in a period that is closed to the end of the phase.     

Impacts of land-cover change on the water flow regulation ecosystem service: Invasive alien plants,fire and their policy implications

Land and water resource issues typically fall under separate governance systems. For example, agricultural policy regulates land-cover change while water departments regulate water quality. However, land-use changes can directly affect water resources. Water flow regulation is a key service which is affected by changes in land-cover but its dynamics are poorly understood by most policy makers and land management organisations. We simulated and quantified the effects of plant invasions on land-cover, hydrological soil characteristics and catchment responsiveness on flow regulation using a hydrological model. The case study was located in the indigenous fynbos shrublands in South Africa. Fynbos requires fire to regenerate, has moderate biomass, occurs mostly in areas with a potential to erode and is prone to invasion by woody plant species, particularly trees. Invasions can affect flow regulation by changing community structure and function and increasing fuel loads. The greater fuel load increases fire intensity and severity which, in turn, changes the hydrological responses of catchments. Few studies have assessed the effects of invasion on hydrological responses but studies on plantations have recorded significant increases in soil water repellence following fire, resulting in increased overland flow similar to impacts of fires in invaded areas. Simulation of clear-felling of pines and different degrees of water repellency increased both the responsiveness of the catchment to rainfall and extreme rainfall events. The simulated fire effects were consistent with other studies of hydrological responses to fire. Our study indicates that invasions of pines and acacias in the study area could substantially increase the risk of flood damage even from moderate rainfall events, and highlights the importance of maintaining flow regulation capacity. New policy approaches are required which take account of the linkages and interactions between land-use choices, water resources and ecosystem services, and address them when considering governance arrangements.     

Devising an electronically supported heritage conservation method for the Valley of Flowers in the Indian Himalayas

The Valley of Flowers is a national park in the Himalayan state of Uttarakhand in India that was classified as a world natural heritage site in 1988. Around 1982, its maximum carrying capacity was fixed at 60 persons per day, which has been called excessive by experts and observers, given the extremely fragile and immensely valuable nature of the Valley's heritage. This, in monetary terms, can be put at millions of dollars, and is considerably more viewed in terms of knowledge of breeding medicinal plants in cold climates that are being affected by climate change, which its microclimate and ecology present. Given the state's poor resources and the fact that tourism is one of the most important industries for development and conservation, this research assesses the heritage value of the Valley and develops a programme for conservation, including a computerised program for permits, whose value can easily be raised from the current paltry Rs 150 per person. Accompanied by fallow periods and marketing through the Internet to aim for educated tourists, the program ensures that the maximum carrying capacity of the Valley is never exceeded, thus spreading out the number of tourists over its 3.5-month season, while allowing flexibility in booking for chance groups and small families that can pay more.     

An integrated decision-support approach in prioritizing risks of non-indigenous species in the face of high uncertainty

When evaluating the risks of future invasions, we often have sparse information on the likelihood that a species will arrive, establish and spread in a new environment, and on the potential impacts should this occur. Conventional risk assessment, therefore, is limited in providing guidance in managing the risk of non-indigenous species (NIS). However, risk management decisions must be made facing these uncertainties to avoid high and irreversible impacts.We develop an integrated ecological economic modeling and deliberative multi-criteria evaluation (DMCE) approach to support group decision-making in risk prioritization, using an example of ten NIS that could potentially impact Australian plant industries. This innovative approach seeks to combine the advantages of dynamic modeling with the benefits of DMCE in assessing and communicating uncertainty. The model unveils the complexity of the socio-ecological system of biological invasion, with a scenario analysis designed to interactively communicate scientific uncertainty to decision-makers. The DMCE provides a structured approach to identifying stakeholders' key concerns in addressing economic, social, and environmental dimensions of NIS risk explicitly. Functioning as a platform for risk communication, the DMCE also offers an opportunity for diverse views to enter the decision-making process and for the negotiation of consensus consensuses.     

Optimal detection strategies for an established invasive pest

We model optimal detection of sub-populations of invasive species that establish ahead of an advancing front. For many invaders, eradication of the main population is an untenable goal, yet it may be possible to treat and eradicate emerging sub-populations once these sub-populations are detected. We embed a dynamically optimal post-detection management plan of sub-populations into a model of optimal detection effort determination and find that optimal detection effort depends, in part, on the distance from the main front: locations closer to the front with shorter management horizons enjoy lower reductions in overall cost from intervention. The uninfested landscape is divided into two zones, characterized by different dynamically optimal management plans: a suppression zone and an eradication zone. In the suppression zone, optimal detection effort increases with distance from the front. At the distance where the suppression zone yields to the eradication zone, optimal detection effort plateaus at its maximum level.     

The Asian clam Corbicula fluminea in the European freshwater-dependent industry: A latent threat or a friendly enemy?

While the biofouler Corbicula fluminea (Müller, 1774) is known to cause great economic losses in North America, studies reporting the problem in Europe are much scarcer. This paper explores the industrial effects of the species in Portugal, the gateway by which the bivalve entered Europe around 30 years ago. National waterworks, major power stations, cement plants, pulp and paper mills and irrigation systems were surveyed. The industrial impacts of the pest were shown to remain relatively mild; irrigation systems are those that seem to be facing more significant economic losses due to infestation. Possible reasons for the apparent discrepancy between this result and the species dispersal in natural ecosystems are discussed, and recommendations on adequate responses to the latent threat are provided. This study may assist the implementation of integrated pest management policies in countries at risk of invasion or recently invaded, and contribute to an understanding of the species’ progression in industrial environments.     

Foot‐and‐mouth disease and the Mexican cattle industry

The objective of this article is to analyze the domestic and international effects of a hypothetical foot‐and‐mouth disease (FMD) outbreak in the Mexican cattle industry. A discrete time dynamic optimization model of the Mexican cattle sector is specified, and linked to domestic and international markets. Economic consequences of FMD outbreaks are simulated over time and under different scenarios. Specific findings and general policy recommendations are provided. The study reports a range of outbreaks from localized to large scale and suggests that changes in economic surplus due to FMD range from a positive net gain of $0.89 to $1.6 billion to a net loss of about $67 billion, depending on the specific mitigation strategy and outbreak scenario.