Environmental triage decisions during a drought

The Murray Darling Basin Current is currently in drought. There are low water levels in most dams, and increased uncertainty about future rainfall. As a result management of the ecosystems in the basin that depend on river flows involves some hard decisions about what assets to save and what assets to let go. This paper models this triage problem using a stochastic and dynamic programming approach. This model is used to identify how optimal management is affected by hysteretic and irreversible effects of drought on ecosystem assets and uncertainty about future climate.Triage, irreversibility, climate change, Environmental Economics and Policy,

Putting Theory into Practice: Market Failure and Market Based Instruments (MBIs)

The use of market-based instruments (MBIs) to provide and protect ecosystem services has gained significant attention in Australia. Despite their popularity, MBIs are not appropriate for the provision of all ecosystem services. Rather, MBIs must be carefully designed given the ecosystem service outcomes desired, while meeting the needs of participants. In this paper we detail the importance of a robust theoretical structure to underpin the selection and design of an MBI. In particular, we demonstrate the role of identifying and analysing the nature of the market failures present, and their implications for instrument design. Our conclusions are illustrated using several regional MBI case studies.Market Based Instruments (MBIs), ecosystem services, conservation

An integrative research framework for enabling transformative adaptation

Transformative adaptation will be increasingly important to effectively address the impacts of climate change and other global drivers on social-ecological systems. Enabling transformative adaptation requires new ways to evaluate and adaptively manage trade-offs between maintaining desirable aspects of current social-ecological systems and adapting to major biophysical changes to those systems. We outline such an approach, based on three elements developed by the Transformative Adaptation Research Alliance (TARA): (1) the benefits of adaptation services; that sub-set of ecosystem services that help people adapt to environmental change; (2) The values-rules-knowledge perspective (vrk) for identifying those aspects of societal decision-making contexts that enable or constrain adaptation and (3) the adaptation pathways approach for implementing adaptation, that builds on and integrates adaptation services and the vrk perspective. Together, these elements provide a future-oriented approach to evaluation and use of ecosystem services, a dynamic, grounded understanding of governance and decision-making and a logical, sequential approach that connects decisions over time. The TARA approach represents a means for achieving changes in institutions and governance needed to support transformative adaptationThe research was supported by CSIRO Land and Water. We thank the Embassy of France in Australia and the Australian Academy of Sciences for funding the first Transformative Adaptation Research Alliance workshop in Canberra, October 27-31, 2014. We thank Craig Beatty, Mirjam Kuzee (IUCN) and Alistair Hobday (CSIRO Oceans and Atmosphere) for reviewing the manuscript and providing constructive comments. The funding partners that have supported this research include the International Climate Initiative (IKI) of the German Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB) and the CGIAR Research Program on Forests, Trees and Agroforestry (CRP-FTA) with financial support from the CGIAR Fun

A Bayesian State Space Approach to Estimating Pest Management Models

Models for pest management need to incorporate information from many subject areas, including biology, agronomy and economics. The information sources are unrelated except by the structural assumptions of the bio-economic model that is used. Rigorous model estimation is often at the expense of ignoring much of the available information. This paper illustrates how a Bayesian approach using the Gibbs sampler can allow the incorporation of potentially valuable prior information. This approach provides posterior distributions for the important model relationships, giving an indication of confidence in the model and providing a natural starting point for stochastic decision making

Modeling profit -maximizing land -allocation behavior

Understanding farmers' decisions about agricultural production, the use of inputs and the allocation of land among crops is central to the analysis of agricultural and environmental policy. Duality theory enables the specification and estimation of models representing production and input use responses to price and policy changes that are consistent with rational behavior. However, there are no equivalent results describing the rational allocation of land among crops. Land-allocation behavior is of increasing interest as many environmental impacts of production are related to land use. This study develops theoretical results describing profit-maximizing land-allocation behavior that are used to structure econometric models of decisions about crop production, land allocation, and input use. Specifically, new comparative static results are developed to describe the behavior of profit-maximizing farmers who manage production systems in which multiple crops compete for allocations of a fixed land area and crops are non-joint in production. These results are used to specify an econometric model of producer behavior that permits joint production but nests the non-joint, land-constrained production model. Some potential applications of this model are illustrated by estimating a model of Saskatchewan crop land-allocation behavior and testing for joint production in the presence of a land constraint

Environmental triage decisions during a drought

The Murray Darling Basin Current is currently in drought. There are low water levels in most dams, and increased uncertainty about future rainfall. As a result management of the ecosystems in the basin that depend on river flows involves some hard decisions about what assets to save and what assets to let go. This paper models this triage problem using a stochastic and dynamic programming approach. This model is used to identify how optimal management is affected by hysteretic and irreversible effects of drought on ecosystem assets and uncertainty about future climate

When should biodiversity tenders contract on outcomes?

Making conservation program payments conditional on outcomes offers potential efficiency and innovation improvements over input based contracts. This paper explores the trade-offs involved in choosing the payment criteria for biodiversity tenders. A model where the budget for a conservation tender can be allocated to input, outcome or mixed payments is used to explore the impacts of hidden actions, adverse selection, and landholder risk aversion on the optimal policy design. We discuss the implications of these results for the design of the ‘Nest Egg’ tender. This tender is targeting habitat and breeding of ground-nesting birds in the New South Wales Murray Catchment

AN OPTIMAL CONTROL MODEL FOR INTEGRATED WEED MANAGEMENT UNDER HERBICIDE RESISTANCE

The presence of weeds which have developed resistance to chemical herbicides is a problem of rapidly growing importance in Australian agriculture. We present an optimal control model of herbicide resistance development in ryegrass, the weed for which resistance is most commonly reported. The model is used to select the optimal combination of chemical and non-chemical control measures taking account of the trade off between short term profits and the long term level of herbicide resistance. Results indicate that given the threat of resistance there are benefits from integrating a combination of chemical and non-chemical control measures. The optimal strategy is found to include a declining herbicide dosage as resistance develops, with compensatory increases in the level of non-chemical control