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1.
Front Big Data ; 4: 662186, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34027401

RESUMO

Most people in the world live in urban areas, and their high population densities, heavy reliance on external sources of food, energy, and water, and disproportionately large waste production result in severe and cumulative negative environmental effects. Integrated study of urban areas requires a system-of-systems analytical framework that includes modeling with social and biophysical data. We describe preliminary work toward an integrated urban food-energy-water systems (FEWS) analysis using co-simulation for assessment of current and future conditions, with an emphasis on local (urban and urban-adjacent) food production. We create a framework to enable simultaneous analyses of climate dynamics, changes in land cover, built forms, energy use, and environmental outcomes associated with a set of drivers of system change related to policy, crop management, technology, social interaction, and market forces affecting food production. The ultimate goal of our research program is to enhance understanding of the urban FEWS nexus so as to improve system function and management, increase resilience, and enhance sustainability. Our approach involves data-driven co-simulation to enable coupling of disparate food, energy and water simulation models across a range of spatial and temporal scales. When complete, these models will quantify energy use and water quality outcomes for current systems, and determine if undesirable environmental effects are decreased and local food supply is increased with different configurations of socioeconomic and biophysical factors in urban and urban-adjacent areas. The effort emphasizes use of open-source simulation models and expert knowledge to guide modeling for individual and combined systems in the urban FEWS nexus.

2.
Coast Manage ; 49(5): 510-531, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-36204115

RESUMO

Ocean and coastal acidification (OCA) present a unique set of sustainability challenges at the human-ecological interface. Extensive biogeochemical monitoring that can assess local acidification conditions, distinguish multiple drivers of changing carbonate chemistry, and ultimately inform local and regional response strategies is necessary for successful adaptation to OCA. However, the sampling frequency and cost-prohibitive scientific equipment needed to monitor OCA are barriers to implementing the widespread monitoring of dynamic coastal conditions. Here, we demonstrate through a case study that existing community-based water monitoring initiatives can help address these challenges and contribute to OCA science. We document how iterative, sequential outreach, workshop-based training, and coordinated monitoring activities through the Northeast Coastal Acidification Network (a) assessed the capacity of northeastern United States community science programs and (b) engaged community science programs productively with OCA monitoring efforts. Our results (along with the companion manuscript) indicate that community science programs are capable of collecting robust scientific information pertinent to OCA and are positioned to monitor in locations that would critically expand the coverage of current OCA research. Furthermore, engaging community stakeholders in OCA science and outreach enabled a platform for dialogue about OCA among other interrelated environmental concerns and fostered a series of co-benefits relating to public participation in resource and risk management. Activities in support of community science monitoring have an impact not only by increasing local understanding of OCA but also by promoting public education and community participation in potential adaptation measures.

3.
Front Mar Sci ; 19: 1-679913, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35693025

RESUMO

Beginning in 2015, the United States Environmental Protection Agency's (EPA's) National Estuary Program (NEP) started a collaboration with partners in seven estuaries along the East Coast (Barnegat Bay; Casco Bay), West Coast (Santa Monica Bay; San Francisco Bay; Tillamook Bay), and the Gulf of Mexico (GOM) Coast (Tampa Bay; Mission-Aransas Estuary) of the United States to expand the use of autonomous monitoring of partial pressure of carbon dioxide (pCO2) and pH. Analysis of high-frequency (hourly to sub-hourly) coastal acidification data including pCO2, pH, temperature, salinity, and dissolved oxygen (DO) indicate that the sensors effectively captured key parameter measurements under challenging environmental conditions, allowing for an initial characterization of daily to seasonal trends in carbonate chemistry across a range of estuarine settings. Multi-year monitoring showed that across all water bodies temperature and pCO2 covaried, suggesting that pCO2 variability was governed, in part, by seasonal temperature changes with average pCO2 being lower in cooler, winter months and higher in warmer, summer months. Furthermore, the timing of seasonal shifts towards increasing (or decreasing) pCO2 varied by location and appears to be related to regional climate conditions. Specifically, pCO2 increases began earlier in the year in warmer water, lower latitude water bodies in the GOM (Tampa Bay; Mission-Aransas Estuary) as compared with cooler water, higher latitude water bodies in the northeast (Barnegat Bay; Casco Bay), and upwelling-influenced West Coast water bodies (Tillamook Bay; Santa Monica Bay; San Francisco Bay). Results suggest that both thermal and non-thermal influences are important drivers of pCO2 in Tampa Bay oxygen, National Estuary Program and Mission-Aransas Estuary. Conversely, non-thermal processes, most notably the biogeochemical structure of coastal upwelling, appear to be largely responsible for the observed pCO2 values in West Coast water bodies. The co-occurrence of high salinity, high pCO2, low DO, and low temperature water in Santa Monica Bay and San Francisco Bay characterize the coastal upwelling paradigm that is also evident in Tillamook Bay when upwelling dominates freshwater runoff and local processes. These data demonstrate that high-quality carbonate chemistry observations can be recorded from estuarine environments using autonomous sensors originally designed for open-ocean settings.

5.
Limnol Oceanogr ; 65(10): 2337-2351, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34121771

RESUMO

Ocean uptake of carbon dioxide (CO2) is causing changes in carbonate chemistry that affect calcification in marine organisms. In coastal areas, this CO2-enriched seawater mixes with waters affected by seasonal degradation of organic material loaded externally from watersheds or produced as a response to nutrient enrichment. As a result, coastal bivalves often experience strong seasonal changes in carbonate chemistry. In some cases, these changes may resemble those experienced by aquacultured bivalves during translocation activities. We mimicked these changes by exposing juvenile hard clams (500 µm, Mercenaria mercenaria) to pCO2 in laboratory upwellers at levels resembling those already reported for northeastern US estuaries (mean upweller pCO2 = 773, 1274, and 1838 µatm) and then transplanting to three grow-out sites along an expected nutrient gradient in Narragansett Bay, RI (154 bags of 100 clams). Prior to the field grow-out, clams exposed to elevated pCO2 exhibited larger shells but lower dry weight per unit volume (dw/V). However, percent increase in dw/V was highest for this group during the 27-day field grow-out, suggesting that individuals with low dw/V after the laboratory treatment accelerated accumulation of dw/V when they were transferred to the bay. Treatments also appeared to affect shell mineral structure and condition of digestive diverticula. Although treatment effects diminished during the field grow-out, clams that were pre-exposed for several weeks to high pCO2 would likely have been temporarily vulnerable to predation or other factors that interact with shell integrity. This would be expected to reduce population recovery from short-term exposures to high pCO2.

6.
Fish Oceanogr ; 28(5): 532-566, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31598058

RESUMO

The timing of recurring biological and seasonal environmental events is changing on a global scale relative to temperature and other climate drivers. This study considers the Gulf of Maine ecosystem, a region of high social and ecological importance in the Northwest Atlantic Ocean and synthesizes current knowledge of (a) key seasonal processes, patterns, and events; (b) direct evidence for shifts in timing; (c) implications of phenological responses for linked ecological-human systems; and (d) potential phenology-focused adaptation strategies and actions. Twenty studies demonstrated shifts in timing of regional marine organisms and seasonal environmental events. The most common response was earlier timing, observed in spring onset, spring and winter hydrology, zooplankton abundance, occurrence of several larval fishes, and diadromous fish migrations. Later timing was documented for fall onset, reproduction and fledging in Atlantic puffins, spring and fall phytoplankton blooms, and occurrence of additional larval fishes. Changes in event duration generally increased and were detected in zooplankton peak abundance, early life history periods of macro-invertebrates, and lobster fishery landings. Reduced duration was observed in winter-spring ice-affected stream flows. Two studies projected phenological changes, both finding diapause duration would decrease in zooplankton under future climate scenarios. Phenological responses were species-specific and varied depending on the environmental driver, spatial, and temporal scales evaluated. Overall, a wide range of baseline phenology and relevant modeling studies exist, yet surprisingly few document long-term shifts. Results reveal a need for increased emphasis on phenological shifts in the Gulf of Maine and identify opportunities for future research and consideration of phenological changes in adaptation efforts.

7.
Environ Manage ; 52(3): 736-47, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23793578

RESUMO

The impacts of strategically located contour prairie strips on sediment and nutrient runoff export from watersheds maintained under an annual row crop production system have been studied at a long-term research site in central Iowa. Data from 2007 to 2011 indicate that the contour prairie strips utilized within row crop-dominated landscapes have greater than proportionate and positive effects on the functioning of biophysical systems. Crop producers and land management agencies require comprehensive information about the Best Management Practices with regard to performance efficacy, operational/management parameters, and the full range of financial parameters. Here, a farm-level financial model assesses the establishment, management, and opportunity costs of contour prairie strips within cropped fields. Annualized, depending on variable opportunity costs the 15-year present value cost of utilizing contour prairie strips ranges from $590 to $865 ha(-1) year(-1) ($240-$350 ac(-1) year(-1)). Expressed in the context of "treatment area" (e.g., in this study 1 ha of prairie treats 10 ha of crops), the costs of contour prairie strips can also be viewed as $59 to about $87 per treated hectare ($24-$35 ac(-1)). If prairie strips were under a 15-year CRP contract, total per acre cost to farmers would be reduced by over 85 %. Based on sediment, phosphorus, and nitrogen export data from the related field studies and across low, medium, and high land rent scenarios, a megagram (Mg) of soil retained within the watershed costs between $7.79 and $11.46 mg(-1), phosphorus retained costs between $6.97 and $10.25 kg(-1), and nitrogen retained costs between $1.59 and $2.34 kg(-1). Based on overall project results, contour prairie strips may well become one of the key conservation practices used to sustain US Corn Belt agriculture in the decades to come.


Assuntos
Agricultura/economia , Conservação dos Recursos Naturais , Modelos Econômicos , Análise Custo-Benefício , Ecossistema , Sedimentos Geológicos , Iowa , Nitrogênio/análise , Fósforo/análise
8.
J Hand Surg Am ; 32(7): 976-83, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17826549

RESUMO

PURPOSE: To report our results after testing the combination of two technologies--angular-stable locking screw implants and Norian SRS cement--in corrective osteotomies of the distal radius in the elderly. This technique eliminates donor site bone-graft morbidity and expands the indications of corrective osteotomies to older patients with osteoporotic bone. METHODS: Our retrospective series include 6 patients (5 women and 1 man) with an average age of 60 years. Three patients had corrections through a dorsal approach, 1 through a volar approach, and 2 through a combined approach. Two corrections included an intraarticular osteotomy. We used 2.4-mm volar T plates in patients approached volarly and 2.4-mm L and T plates for those approached dorsally; the osseous defect was filled with bone cement (Norian SRS). Range of motion and grip strength were measured at 16 months average follow-up. Standard wrist radiographs were taken to evaluate alignment and determine improvement. At final follow-up, patients completed the Modified Mayo Wrist score, the Modified Gartland and Werley score, and the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire. RESULTS: There were no perioperative complications. All corrective osteotomies healed. One patient required a Darrach procedure at 6 months. The average wrist and forearm motion was 77% of the opposite side and grip strength 88% of the opposite side. The average total correction in the sagittal plane was 22 degrees with all patients returning to neutral or better alignment. The average ulnar variance improvement was 2 mm. Average postoperative DASH was 28 points; average Modified Mayo Wrist score was 68; and the Modified Gartland and Werley score averaged 9 points. CONCLUSIONS: We believe that corrective osteotomy of the distal radius in the elderly using angular stable implants and Norian calcium phosphate cement is a safe and predictable surgical technique, even in patients with underlying osteoporosis. It eliminates donor site morbidity, and patient-rated outcome measures demonstrated acceptable daily living function return.


Assuntos
Cimentos Ósseos/uso terapêutico , Placas Ósseas , Fosfatos de Cálcio/uso terapêutico , Fraturas Mal-Unidas/cirurgia , Osteotomia/métodos , Rádio (Anatomia)/cirurgia , Idoso , Avaliação da Deficiência , Feminino , Seguimentos , Força da Mão , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas do Rádio/cirurgia , Amplitude de Movimento Articular , Estudos Retrospectivos , Resultado do Tratamento
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