Rethinking urban park irrigation under climate change.

Climate change is forcing cities to reassess their water management practices, particularly for water-intensive applications like park irrigation. If water scarcity requires governments to deviate from current park management norms and allocate less water towards parks, it is essential that park managers design spaces that maintain community wellbeing. We apply the hedonic pricing method and use detailed park management information to assess the value of parks in a region where local climatic conditions require extensive irrigation to keep turf green, and where climate change is further constraining water supplies. Here we show that the impacts of irrigation on the value of parks differ depending on the dwelling types of the nearby housing populations that they serve. In most cases, the convention that parks have to be irrigated to deliver ecosystem services to the public is supported. However, we find that non-irrigated park areas are also valued positively by nearby apartment dwellers. Accelerating rates of urbanization and shifts towards high-density living may support the development of more diverse park options that are less water-intensive. Increased visibility of these alternative park forms, which could include more areas of native vegetation that do not require irrigation, may subsequently influence public expectations for landscape design.

Tackling communication and analytical problems in environmental planning: Expert assessment of key definitions and their relationships.

Inadequate definition of key terms and their relationships generates significant communication and analytical problems in environmental planning. In this work, we evaluate an ontological framework for environmental planning designed to combat these problems. After outlining the framework and issues addressed, we describe its evaluation by a group of experts representing a range of expertise and institutions. Experts rated their level of agreement with 12 propositions concerning the definitions and models underpinning the framework. These propositions, in turn, were used to assess three assumptions regarding the expected effectiveness of the framework and its contribution to addressing the abovementioned planning problems. In addition to point-based best estimates of their agreement with propositions, expert ratings were also captured on a continuous interval-valued scale. The use of intervals addresses the challenge of measuring and modelling uncertainty associated with complex assessments such as those provided by experts. Combined with written anonymous expert comments, these data provide multiple perspectives on the level of support for the approach. We conclude that the framework can complement existing planning approaches and strengthen key definitions and related models, thus helping avoid communication and analytical problems in environmental planning. Finally, experts highlighted areas that require further development, and we provide recommendations for improving the framework.

Wellbeing, values, and planning in environmental management.

Concepts of 'human values' and 'wellbeing' are central in environmental planning, especially during the group deliberations that underpin expert and participatory processes. However, there are long-standing, unresolved controversies concerning both concepts with many debates being highly theoretical. Therefore, we suggest it is more productive to develop definitions and models that are task-specific (mid-level theory). To this end, we use purpose-built value sets and models to explain the relationships among values and wellbeing, and to demarcate values, desires, and personality. The derived concepts are designed for group deliberations and could readily be combined with existing decision support tools, such as structured decision making. Outputs from the work also inform current debates within the environmental domain including, for example, those surrounding the intrinsic value of nature, and ideas concerning plural values versus a single overarching value (monism). We also define 'wellbeing' as an evaluative statement that supports assessments of trade-offs and co-benefits.

Environmental cost of using poor decision metrics to prioritize environmental projects.

Conservation decision makers commonly use project-scoring metrics that are inconsistent with theory on optimal ranking of projects. As a result, there may often be a loss of environmental benefits. We estimated the magnitudes of these losses for various metrics that deviate from theory in ways that are common in practice. These metrics included cases where relevant variables were omitted from the benefits metric, project costs were omitted, and benefits were calculated using a faulty functional form. We estimated distributions of parameters from 129 environmental projects from Australia, New Zealand, and Italy for which detailed analyses had been completed previously. The cost of using poor prioritization metrics (in terms of lost environmental values) was often high--up to 80% in the scenarios we examined. The cost in percentage terms was greater when the budget was smaller. The most costly errors were omitting information about environmental values (up to 31% loss of environmental values), omitting project costs (up to 35% loss), omitting the effectiveness of management actions (up to 9% loss), and using a weighted-additive decision metric for variables that should be multiplied (up to 23% loss). The latter 3 are errors that occur commonly in real-world decision metrics, in combination often reducing potential benefits from conservation investments by 30-50%. Uncertainty about parameter values also reduced the benefits from investments in conservation projects but often not by as much as faulty prioritization metrics.