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,

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

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.Research and Development/Tech Change/Emerging Technologies,

Putting theory into practice: market failure and market based instrument design

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

Trees as brokers in social networks: Cascades of rights and benefits from a Cultural Keystone Species

Indigenous trees play key roles in West African landscapes, such as the ne´re´ tree (Parkia biglobosa (Jacq.) R.Br. ex G.Don). We applied social–ecological network analysis to understand the social–ecological interactions around ne´re´. We documented the benefits ne´re´ provides and the multiple social interactions it creates amongst a large range of actors. The flows of rights over the trees and benefits from them formed two hierarchical networks, or cascades, with different actors at the top. The two forms of power revealed by the two cascades of rights and benefits suggest possible powers and counter-powers across gender, ethnicity, and age. We documented how the tree catalyses social interactions across diverse groups to sustain vital social connections, and co-constitute places, culture, and relationships. We argue that a paradigm shift is urgently needed to leverage the remarkable untapped potential of indigenous trees and Cultural Keystone Species in current global restoration and climate change agendas

Linking social and biophysical systems to inform long-term, strategic management of coral reefs

Coral reefs are one of the ecosystems most sensitive to climate change. The recent loss and degradation of coral reef ecosystems is expected to continue even if global warming is limited to 1.5 degrees C above pre-industrial levels. There is therefore an urgent need to develop new technologies and management approaches to coral reef conservation. Emerging technologies, however, bring new challenges for decision making as they are associated with novel risks and impacts on the reef system. We argue that accounting for multiple biophysical thresholds and identifying key decisions in the planning process are crucial to avoid perverse outcomes in coral reef conservation. We identify opportunities to apply an Adaptation Pathways (AP) framework combined with a 'values, rules and knowledge' approach to facilitate long-term and large-scale coral reef conservation by explicitly considering uncertainty with climate change impacts in the decision-making process. The AP process can be used to reconcile the diverse values of stakeholders, scientific and cultural knowledge about the system, and the policy and regulatory context within which management must occur, in order to achieve robust long-term management

Informing climate adaptation pathways in multi-use woodland landscapes using the values-rules-knowledge framework

An emerging planning framework for climate adaptation focuses on interactions among societal values, institutional rules and scientific and experiential knowledge about biophysical impacts of climate change and adaptation options. These interactions shape the decision context that can enable or constrain effective adaptation. To illustrate the operationalisation of this ‘values-rules-knowledge’ (VRK) framework we developed biophysical adaptation pathways for agricultural landscapes of south-eastern Australia, which are expected to become warmer and drier under climate change. We used the VRK framework to identify potential constraints to implementing the pathways. Drawing on expert knowledge, published literature, biodiversity modelling and stakeholder workshops we identified potential adaptation pathways for (1) the production matrix, (2) high conservation value remnant eucalypt woodlands, and (3) woodland trees. Adaptation options included shifts from mixed cropping-grazing to rangeland grazing or biomass enterprises; promoting re-assembly of native ecological communities; and maintaining ecosystem services and habitat that trees provide. Across all pathways, applying the VRK framework elucidated fifteen key implementation constraints, including limits to farm viability, decreasing effectiveness of environmental legislation and conflicting values about exotic plants. Most of the constraints involved interactions among VRK; 13 involved rules, eight involved values, and seven involved knowledge. Value constraints appeared most difficult to address, whereas those based on rules or knowledge were more tangible. The lower number of knowledge constraints may reflect the scale of our analysis (which focused on decision points in pre-defined pathways); new knowledge and participatory approaches would likely yield a richer set of scenarios. We conclude that the VRK framework helps connect the biophysical knowledge-based view of adaptation with a perspective on the need for changes in social systems, enabling targeting of constraints to adaptation. Our focus on pathways and decision points in different sectors of the multi-use landscape highlighted the importance of group and higher level planning and policy for balancing the collective outcomes of multiple decisions by many land managers.This research was funded by CSIRO Land and Water and contributes to the CSIRO Enabling Adaptation Pathways Project (EAP) and the Transformative Adaptation Research Alliance (TARA), an international network of researchers and practitioners dedicated to the development and implementation of novel approaches to transformative adaptation to global change