David Yoskowitz

Role and value of nitrogen regulation provided by oysters (Crassostrea virginica) in the Mission-Aransas Estuary, Texas, USA.

Suspension-feeding activities of oysters impart a potentially significant benefit to estuarine ecosystems via reduction of water column nutrients, plankton and seston biomass, and primary productivity which can have a significant impact on human well-being. This study considered nitrogen regulation by eastern oysters Crassostrea virginica in the Mission-Aransas Estuary, Texas, USA, as a function of denitrification, burial, and physical transport from the system via harvest. Oyster reefs were estimated to remove 502.5 kg N km−2 through denitrification of biodeposits and 251.3 kg N km−2 in burial of biodeposits to sediments. Nitrogen is also physically transported out of the estuary via harvest of oysters. Commercial harvest of oysters in the Mission-Aransas Estuary can remove approximately 21,665 kg N per year via physical transport from the system. We developed a transferable method to value the service of nitrogen regulation by oysters, where the potential cost equivalent value of nitrogen regulation is quantified via cost estimates for a constructed biological nutrient removal (BNR) supplement to a wastewater treatment plant. The potential annual engineered cost equivalent of the service of nitrogen regulation and removal provided by reefs in the Mission-Aransas Estuary is

Price Dispersion and Price Discrimination: Empirical Evidence from a Spot Market for Water

293,993 yr−1. Monetizing ecosystem services can help increase awareness at the stakeholder level of the importance of oysters beyond commercial fishery values alone.

The Retail Travels of the U.S. Greenback: A Comparative Study of Currency Substitution Along the U.S.-Canadian and U.S.-Mexican Borders

This note shows the existence of price dispersion and pricediscrimination in a spot market for water.Several behaviors contributing to this dispersion/discrimination arefound for both the seller and buyer in this relatively competitive market,and examples are given of each. Using some previous theoretical work,the common thread linking the differing behaviors is shown to bediffering levels of information and search costs.

A Study of Small Neighborhood Tienditas in Central America

This currency substitution study explores the extent of retail firm-level U.S. dollar acceptance in Canada and Mexico. Employing a stratified random sampling approach of retail business in the border region, results demonstrate that all Mexican firms (N = 300/300) and nearly all Canadian (N = 257/261) firms accept the U.S. dollar in retail transactions. Of greater interest is the difference between firms in the two countries in how acceptance of the U.S. dollar is operationalized. On average, U.S. dollar sales of Canadian border firms comprise just 3.4% of total sales whereas U.S. dollar sales of Mexican firms encompass 23.7% of total sales. Our results also indicate a stark contrast as to the effective exchange rate for U.S. dollar acceptance— Canadian firms typically charge a premium (2.1% on average) while 69.3% of Mexican firms transacted business at a discount (−0.8% on average). Additional analyses further refine the currency substitution distinctions between Canadian and Mexican firms in the sample including a logistical regression which reveals significant differences as to firm-level predictors of U.S. dollar acceptance (whether at a discount or premium).

Integrated ecosystem services assessment: Valuation of changes due to sea level rise in Galveston Bay, Texas, USA

We describe and benchmark tienditas (in-home convenience-like retail stores) and the tiendita business sector using a large sample of 850 tienditas from Nicaragua and El Salvador. Three research questions concerning tiendita business dynamism, informality, and competitive scope shape our article. In general, we find that tienditas may range from subsistence operations to dynamic business enterprises primarily run by female microentrepreneurs; they typically skirt government oversight; and they compete fiercely in a monopolistically competitive business environment.

The Efficacy of Microfinance at the Sectoral Level: Urban Pulperías in Matagalpa, Nicaragua

The goal of the present study was to identify the potential changes in ecosystem service values provided by wetlands in Galveston Bay, Texas, USA, under the Intergovernmental Panel on Climate Change (IPCC) A1B max (0.69u2009m) sea level rise scenario. Built exclusively upon the output produced during the Sea Level Affecting Marshes Model 6 (SLAMM 6) exercise for the Galveston Bay region, this study showed that fresh marsh and salt marsh present a steady decline from 2009 (initial condition) to 2100. Fresh marsh was projected to undergo the biggest changes, with the loss of approximately 21% of its extent between 2009 and 2100 under the A1B max scenario. The percentages of change for salt marsh were less prominent at approximately 12%. This trend was also shown in the values of selected ecosystem services (disturbance regulation, waste regulation, recreation, and aesthetics) provided by these habitats. An ordinary least squares regression was used to calculate the monetary value of the selected ecosystem services provided by salt marsh and fresh marsh in 2009, and in 2050 and 2100 under the A1B max scenario. The value of the selected services showed potential monetary losses in excess of US

Operationalizing Blue Carbon in the Mission-Aransas National Estuarine Research Reserve, Texas

40 million annually in 2100, compared to 2009 for fresh marsh and more than

Spot Market for Water along the Texas Rio Grande: Opportunities for Water Management

11 million for salt marsh. The estimates provided here are only small portions of what can be lost due to the decrease in habitat extent, and they highlight the need for protecting not only built infrastructure but also natural resources from sea level rise. Integr Environ Assess Manag 2017;13:431-443.

Proceedings of the Gulf of Mexico Ecosystem Services Workshop

This chapter sheds light on one of the largest segments of the microfinance industry in Latin America - the in-home convenience store or pulper?a . Specifically, it addresses the impact, viability and efficacy of microfinance on pulper?as , a sector that comprises up to one-third of the microfinance loan market in Central America, in a single research locale. The research site is Matagalpa, Nicaragua, the second largest municipality in the country where the authors undertook a survey of 279 urban pulper?as . Their investigation focuses on how microfinance funding assisted those who accessed it. The chapter reports on the relevant literature, and highlights and provides context for research location. It details the methodology employed, reports research results, and describes the impact of microfinance with reference to qualitative interviews of pulperistas . The chapter also offers a discussion of the findings. Keywords:efficacy; Matagalpa; microfinance; Nicaragua; pulper?as

Gulf of Mexico offshore ecosystem services: stakeholder valuation workshops

Abstract Recently, greater interest in the resilience of coastal habitat ecosystem services in the northern Gulf of Mexico has emerged due in part to an expansion of mangroves into areas previously dominated by salt marshes. To operationalize coastal wetland ecosystem services for decision-making, there is a need to clarify how salt marshes and mangroves function in this region. The goal of this research is to operationalize blue carbon (carbon stored in coastal habitats) within the Mission-Aransas National Estuarine Research Reserve, TX by documenting what we know about blue carbon within the study area, identifying data gaps and future research needs, and using available knowledge to inform management and decision-making within the Reserve. Our research shows that there is a lack of data within the Reserve on mangrove aboveground biomass, belowground biomass and soil carbon and on salt marsh soil carbon. There is also a dearth of information on wetland carbon sequestration and emission rates within the Reserve, making it challenging to inform management and develop a market for blue carbon.