The objective of this project is to make significant strides in bridging the gap between scientific knowledge and current management needs by integrating existing biogeochemical model frameworks, field measurements, and experimental work toward the goals of (1) delineating atmospheric and eutrophication drivers of Chesapeake Bay acidification and improve our understanding of estuarine carbonate chemistry, (2) developing a spatially explicit framework to identify shellfish restoration areas most and least prone to acidification impacts, and (3) better understanding feedbacks associated with future environmental conditions and shellfish restoration goals estuary-wide and within a model tributary. This effort includes (1) a field campaign to make the first comprehensive study of the spatial and temporal variability in the carbonate system in Chesapeake Bay, (2) experiments to quantify both carbonate and nutrient exchange between intact oyster reefs and the surrounding water while measuring response of these fluxes to reef structure and acidification, and (3) an advancement in numerical modeling tools to simultaneously simulate the dynamics of eutrophication, hypoxia, carbonate chemistry, and oyster reef growth and interaction with the water-column under present and future conditions.
The California Current System (CCS) is one of the most biologically productive regions of the world ocean, but seasonal upwelling of low oxygen and low-pH waters makes it particularly vulnerable to even small additional reductions in O2 and/or pH, which have both been observed in recent decades. Three prominent coastal phenomena have been implicated in precisely these changes: 1) large scale acidification and deoxygenation of the ocean associated with climate warming, 2) natural climate variability, and 3) anthropogenic pollution of coastal waters, especially from nutrient discharge and deposition. The relative importance of these drivers has not been systematically evaluated, and yet is critical information in any cost-effective strategy to manage coastal resources at local scales. Disentangling the magnitude and interaction of these different ecosystem stresses requites an integrated systems modeling approach that is carefully validated against available datasets.
The goals of this project are three-fold: 1) develop an ocean hypoxia and acidifcation (OHA) model of the CCS (Baja California to British Columbia), comprising the circulation, biogeochemical cycles, and lower-trophic ecosystem of the CCS, with regional downscaling in the Southern California Bight, Central Coast, and the Oregon Coast; 2) use the model to understand the relative contributions of natural climate variability, anthropogenically induced climate change, and anthropogenic inputs on the status and trends of OHA in the CCS; and 3) transmit these findings to coastal zone mangers and help them explore the implications for marine resource management and pollution control.
This project uses data from experimental studies on the biological effects of ocean acidification (OA), largely funded by NOAA's Ocean Acidification Program (OAP), to construct realistic population‐process models of marine finfish populations. The models are of an individual‐ based model (IBM) category that use detailed biological responses of individuals to OA. This tool synthesizes OA data in two different ways. First, it accumulates and connects data through mechanistic relationships between the environment and fish life‐history. Second, it allows exploration of the population‐level consequences of CO2 effects (the source of OA) which explicitly include population effects carried over from the highly sensitive early life‐stages (ELS). This information is fundamental to understanding the community and ecosystem effects of OA on living marine resources.
Project efforts are directed at two different, complimentary levels. At the more detailed, specific level, winter flounder – an economically important, well‐studied fish of Mid‐Atlantic to New England waters – will be used as a model subject. Prior studies on winter flounder, augmented by OAP‐funded experimental work at NOAA/NEFSC, will provide estimates of CO2 effects on key life‐history and ecological parameters (e.g., fertilization, larval growth, development, and survival). An IBM previously developed by the PIs will be updated and expanded to include OA effects on these parameters. The winter flounder OA‐IBM will be exercised by evaluating the responses of the ELSs of this species under multiple scenarios: high average levels of CO2 representing future oceans in shelf habitats; high and variable CO2 depicting future inshore, estuarine habitats; and covariances of CO2 with other environmental stressors (e.g., warmer waters, hypoxia). At a general level and applicable to other species, the project will develop a web‐based tool that allows users to add details from other marine finfish of the NE USA and OA‐affected processes as relevant OA data on those species become available.
The aim of this project was to forecast effects of ocean acidification on the commercially important Alaska crab stocks including the Bristol Bay red king crab (BBRKC) fishery, which is part of a modern fisheries management program, the Bering Sea and Aleutian Islands (BSAI) crab rationalization program. To investigate the biological and economic impacts of OA, a linked bioeconomic model was developed that a) integrates predictions regarding trends over time in ocean pH, b) separates life-history stages for growth and mortality of juveniles and adults, and c) includes fishery impacts by analyzing catch and effort in both biological and economic terms. By coupling a pre-recruitment component with post-recruitment dynamics, the BBRKC bioeconomic model incorporates effects of OA on vulnerable juvenile crabs in combination with effects of fishing on the BBRKC population as a whole. Many types of projections under management strategies can be made using linked bioeconomic models.