Search

Climate change may affect mental health. We conducted an umbrella review of meta-analyses examining the association between mental health and climate events related to climate change, pollution and green spaces. We searched major bibliographic databases and included meta-analyses with at least five primary studies. Results were summarized narratively. We included 24 meta-analyses on mental health and climate events (n = 13), pollution (n = 11), and green spaces (n = 2) (two meta-analyses provided data on two categories). The quality was suboptimal. According to AMSTAR-2, the overall confidence in the results was high for none of the studies, for three it was moderate, and for the other studies the confidence was low to critically low. The meta-analyses on climate events suggested an increased prevalence of symptoms of post-traumatic stress, depression, and anxiety associated with the exposure to various types of climate events, although the effect sizes differed considerably across study and not all were significant. The meta-analyses on pollution suggested that there may be a small but significant association between PM2.5, PM10, NO2, SO2, CO and mental health, especially depression and suicide, as well as autism spectrum disorders after exposure during pregnancy, but the resulting effect sizes varied considerably. Serious methodological flaws make it difficult to draw credible conclusions. We found reasonable evidence for an association between climate events and mental health and some evidence for an association between pollution and mental disorders. More high-quality research is needed to verify these associations. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a meta-analysis of the economic valuation literature on ecosystem services provided by wetlands in agricultural landscapes. We focus on the value of three regulating services, namely flood control, water supply and nutrient recycling. We construct a database containing 66 value estimates, mainly for wetlands in the US and Europe but also a substantial number in developing countries. Values are standardised to USD per hectare per year. The mean (median) values are found to be 6923 (427)USD/ha/yr for flood control; 3389 (57)USD/ha/yr for water supply; and 5788 (243)USD/ha/yr for nutrient recycling. The values of these services are highly variable across individual wetland sites due to, amongst other factors, differences in wetland type, size, the scarcity or abundance of other wetlands in the surrounding landscape, and the socio-economic characteristics of the beneficiaries of these services. We include explanatory variables in the meta-analysis to account for these influences on estimated wetland values. GIS is used to quantify potentially important spatial variables. The meta-regression is used to produce a value function for wetland regulating services, which can be used to transfer values to other wetland sites while controlling for site and context specific characteristics. An illustrative value transfer exercise is conducted to estimate global values for wetland regulating services in agricultural landscapes. [Copyright &y& Elsevier]

Abstract: This paper examines the value of ecosystem services provided by mangroves. It presents a meta-analysis of the economic valuation literature and applies the estimated value function to assess the value of mangroves in Southeast Asia. We construct a database containing 130 value estimates, largely for mangroves in Southeast Asia. Values are standardised to US$ per hectare per year in 2007 prices. The mean and median values are found to be 4185 and 239 US$/ha/year respectively. The values of mangrove ecosystem services are highly variable across study sites due to, amongst other factors, the bio-physical characteristics of the site and the socio-economic characteristics of the beneficiaries of ecosystem services. We include explanatory variables in the meta-analysis to account for these influences on estimated mangrove values. A geographic information system (GIS) is used to quantify potentially important spatial variables, including the abundance of mangroves, the population of beneficiaries, and the density of roads in the vicinity of each study site. The meta-analytic value function is used to estimate the change in value of mangrove ecosystem services in Southeast Asia under a baseline scenario of mangrove loss for the period 2000–2050. The estimated foregone annual benefits in 2050 are US$ 2.2 billion, with a prediction interval of US$ 1.6–2.8 billion. [Copyright &y& Elsevier]

Abstract: This paper gives an overview of the value of ecosystem services of 10 main biomes expressed in monetary units. In total, over 320 publications were screened covering over 300 case study locations. Approximately 1350 value estimates were coded and stored in a searchable Ecosystem Service Value Database (ESVD). A selection of 665 value estimates was used for the analysis. Acknowledging the uncertainties and contextual nature of any valuation, the analysis shows that the total value of ecosystem services is considerable and ranges between 490 int$/year for the total bundle of ecosystem services that can potentially be provided by an ‘average’ hectare of open oceans to almost 350,000 int$/year for the potential services of an ‘average’ hectare of coral reefs. More importantly, our results show that most of this value is outside the market and best considered as non-tradable public benefits. The continued over-exploitation of ecosystems thus comes at the expense of the livelihood of the poor and future generations. Given that many of the positive externalities of ecosystems are lost or strongly reduced after land use conversion better accounting for the public goods and services provided by ecosystems is crucial to improve decision making and institutions for biodiversity conservation and sustainable ecosystem management. [Copyright &y& Elsevier]

Urban open space provides a number of valuable services to urban populations, including recreational opportunities, aesthetic enjoyment, environmental functions, and may also be associated with existence values. In separate meta-analyses of the contingent valuation (CV) and hedonic pricing (HP) literature we examine which physical, socio-economic, and study characteristics determine the value of open space. The dependent variable in the CV meta-regression is defined as the value of open space per hectare per year in 2003 US$, and in the HP model as the percentage change in house price for a 10 m decrease in distance to open space. Using a multi-level modelling approach we find in both the CV and HP analyses that there is a positive and significant relationship between the value of urban open space and population density, indicating that scarcity and crowdedness matter, and that the value of open space does not vary significantly with income. Further, urban parks are more highly valued than other types of urban open space (forests, agricultural and undeveloped land) and methodological differences in study design have a large influence on estimated values from both CV and HP. We also find important regional differences in preferences for urban open space, which suggests that the potential for transferring estimated values between regions is likely to be limited. [Copyright &y& Elsevier]

The values of goods and services provided by wetland ecosystems are examined through a meta-analysis of an expanded database of wetland value estimates and with a focus on human-made wetlands. This study extends and improves upon previous meta-analyses of the wetland valuation literature in terms of the number of observations, geographical coverage, wetland class and integrity, and the measurement of the effects of scarcity and anthropogenic pressure. We find that water quality improvement, nonconsumptive recreation, and provision of natural habitat and biodiversity are highly valued services. Substitution effects are observed through the negative correlation between values and abundance of other wetlands. Wetland values are found to increase with anthropogenic pressure. An extended metaregression model with cross effects shows that the valuation of specific services varies with the type of wetland producing them. Human-made wetlands are highly valued for biodiversity enhancement, water quality improvement, and flood control. [ABSTRACT FROM AUTHOR]

Abstract: Coral reefs are highly productive ecosystems that provide a variety of valuable goods and services, including recreational opportunities. The open-access nature and public good characteristics of coral reefs often result in them being undervalued in decision making related to their use and conservation. In response to this, there now exists a substantial economic valuation literature on coral reefs. For the purposes of conducting a meta-analysis of this literature, we collected 166 coral reef valuation studies, 52 of which provided sufficient information for a statistical meta-analysis, yielding 100 separate value observations in total. Focusing on recreational values, we use US$ per visit as the dependent variable in our meta-analysis. The meta-regression results reveal a number of important factors in explaining variation in coral reef recreational values, notably the area of dive sites and the number of visitors. Different valuation methods are shown to produce widely different values, with the contingent valuation method producing significantly lower value estimates. Using a multi-level modelling approach we also control for authorship effects, which proves to be highly significant in explaining variation in value estimates. We assess the prospects for using this analysis for out-of-sample value transfer, and find average transfer errors of 186%. We conclude that there is a need for further high-quality valuation research on coral reefs. [Copyright &y& Elsevier]