Contributions of Ecosystem Services to Human Well-Being in Puerto Rico.

Ecosystem services, including availability of greenspace, clean air, and clean water, can have benefits to human well-being, but their relative importance compared to economic or social services is often overlooked. In Puerto Rico, for example, improving community well-being, including economic and cultural opportunities, human health, and safety, are often overarching goals of environmental management decisions, but the degree to which improvements in ecological condition and provision of ecosystem services could impact local communities is complicated by wide variation in social and economic conditions. This study quantifies and maps neighborhood-scale indicators of human well-being and ecosystem services for Puerto Rico to better understand the degree to which ecosystem services provisioning, alongside co-occurring social and economic services, explains variability in a number of indicators of human well-being. In Puerto Rico, variability in indicators of human well-being were predominately explained by economic services related to accumulating income and personal savings, and social services, including availability of family services, healthcare services, and access to communication technology. Despite the large explanatory power of economic and social services, however, the analysis detected that substantial portions of well-being, in particular education and human health, could be explained by variability in ecosystem services over space and time, especially availability of greenspace. Linking ecosystem services to multivariate elements of human well-being can serve to complement more traditional community planning or environmental management efforts by helping identify potential unintended consequences or overlooked benefits of decisions.

Who Benefits from National Estuaries? Applying the FEGS Classification System to Identify Ecosystem Services and their Beneficiaries.

In spite of their perceived value, the widespread implementation of ecosystem services assessments has been limited because of perceptions of being too technical, too expensive, or requiring special expertise. For example, federal estuary management programs have widely used ecosystem services concepts to frame management issues and communicate with stakeholders. Yet, indicators assessed, monitored, and reported in estuarine management still have traditionally focused on ecological conditions, with weak connections, if any, to social or economic outcomes. Approaches are needed which expand the range of ecosystem services that can be considered, link ecosystem services explicitly to different stakeholder groups, facilitate effective communication with economists and other social scientists, and expand the array of available valuation techniques. We applied the concept of final ecosystem goods and services to review the broad suite of ecosystem services and their beneficiaries relevant to the management of two federal programs for estuary management, the National Estuary Program (NEP) and the National Estuarine Research Reserve System (NERRS). The Final Ecosystem Goods and Services Classification System provided a structured framework for connecting ecosystem services to their beneficiaries and the environments providing them. Document analysis of management plans assessed the degree to which these programs consider ecosystem services, their beneficiaries, and habitats within the estuarine watershed. The hierarchical list of final ecosystem goods and services generated from document analysis serves as a tool for defining management goals, identifying stakeholders, developing meaningful indicators, and conducting valuation studies in estuarine management planning efforts. Though developed here for estuarine management, the keyword hierarchy and final ecosystem goods and services approach have broad applicability and transferability to other environmental management scenarios.

Linking Water Quality to Aedes aegypti and Zika in Flood-Prone Neighborhoods.

The ability of ecosystems to regulate water quality and flood events has been linked to health outcomes, including mosquito-borne illnesses. In the San Juan Bay Estuary watershed of Puerto Rico, habitat alterations and land-use development have disrupted watershed hydrology, exacerbating wastewater discharges and subjecting some neighborhoods to frequent flooding events. In 2016, the mosquito-borne illness Zika became a new cause for concern. We hypothesized that nutrient-enriched flood water could provide pulses of supplemental nutrients to local mosquito populations. We conducted a field study in six neighborhoods adjacent to the estuary to assess whether environmental variability of nutrient inputs could be linked to breeding habitat containers, Aedes aegypti larvae and adults, and the acquisition of Zika virus by adult mosquitoes. The most frequently flooded neighborhood had consistently higher levels of nitrogen in estuary water, leaf detritus, containers, and adult mosquitoes compared to other neighborhoods. Adult body nitrogen was significantly related to both nitrogen content of containers and leaf detritus from the local trapping area. Disseminated Zika concentration in adult Ae. aegypti tended to decrease as body carbon and nitrogen increased. Our study provides preliminary evidence that environmental variability in nutrient inputs can influence viral acquisition by mosquito vectors. This suggests that management actions to reduce flooding and improve water quality should go hand-in-hand with more traditional vector control methods, such as aerial spraying, to help control spread of vector-borne diseases.

Predicting coral bleaching in response to environmental stressors using 8 years of global-scale data.

Coral reefs have experienced extensive mortality over the past few decades as a result of temperature-induced mass bleaching events. There is an increasing realization that other environmental factors, including water mixing, solar radiation, water depth, and water clarity, interact with temperature to either exacerbate bleaching or protect coral from mass bleaching. The relative contribution of these factors to variability in mass bleaching at a global scale has not been quantified, but can provide insights when making large-scale predictions of mass bleaching events. Using data from 708 bleaching surveys across the globe, a framework was developed to predict the probability of moderate or severe bleaching as a function of key environmental variables derived from global-scale remote-sensing data. The ability of models to explain spatial and temporal variability in mass bleaching events was quantified. Results indicated approximately 20% improved accuracy of predictions of bleaching when solar radiation and water mixing, in addition to elevated temperature, were incorporated into models, but predictive accuracy was variable among regions. Results provide insights into the effects of environmental parameters on bleaching at a global scale.

Richness-productivity relationships between trophic levels in a detritus-based system: significance of abundance and trophic linkage.

Most theoretical and empirical studies of productivity-species richness relationships fail to consider linkages among trophic levels. We quantified productivity-richness relationships in detritus-based, water-filled tree-hole communities for two trophic levels: invertebrate consumers and the protozoans on which they feed. By analogy to theory for biomass partitioning among trophic levels, we predicted that consumer control would result in richness of protozoans in the lower trophic level being unaffected by increases in productivity, whereas richness of invertebrate consumers would increase with productivity. Our data were consistent with this prediction: consumer richness increased linearly, but protozoan richness was unrelated to changes in productivity. The productivity-richness relationships for all taxa combined were not necessarily consistent with relationships within each trophic level. We used path analysis to investigate the mechanisms that may produce the observed responses of trophic levels to changes in productivity. We tested the importance of the direct effect of productivity on richness and the indirect effect of productivity mediated by effects on total abundance. For protozoans, only direct effects of productivity on richness were important, but both direct and indirect effects of productivity on richness were important for invertebrates. Protozoan richness was strongly affected by top-down impacts of abundance of invertebrates. These results are consistent with theory on biomass partitioning among trophic levels and suggest a strong link between richness and abundance within and between trophic levels. Understanding how trophic level interactions determine productivity-richness relationships will likely be necessary in order for us to achieve a comprehensive understanding of the determinants of diversity.

The combined effects of pathogens and predators on insect outbreaks.

The economic damage caused by episodic outbreaks of forest-defoliating insects has spurred much research, yet why such outbreaks occur remains unclear. Theoretical biologists argue that outbreaks are driven by specialist pathogens or parasitoids, because host-pathogen and host-parasitoid models show large-amplitude, long-period cycles resembling time series of outbreaks. Field biologists counter that outbreaks occur when generalist predators fail, because predation in low-density defoliator populations is usually high enough to prevent outbreaks. Neither explanation is sufficient, however, because the time between outbreaks in the data is far more variable than in host-pathogen and host-parasitoid models, and far shorter than in generalist-predator models. Here we show that insect outbreaks can be explained by a model that includes both a generalist predator and a specialist pathogen. In this host-pathogen-predator model, stochasticity causes defoliator densities to fluctuate erratically between an equilibrium maintained by the predator, and cycles driven by the pathogen. Outbreaks in this model occur at long but irregular intervals, matching the data. Our results suggest that explanations of insect outbreaks must go beyond classical models to consider interactions among multiple species.