Fig 1 - uploaded by Caitlin Fong
Content may be subject to copyright.
Source publication
Humans have increased nitrogen inputs to estuaries, necessitating research on the patterns of these resource subsidies. When originating outside an estuary, nitrogen is a resource subsidy. This subsidy can be delivered with a variety of temporal patterns, ranging from presses to pulses. In other communities, press versus pulse subsidies has substan...
Context in source publication
Context 1
... subsidy regime of 5 estuaries in Southern California by quantifying water column nitrate (NO 3 ) and ammonium (NH 4 ) concentrations; these concentrations are reflective of nutrient inputs as well as biological and physical processes. These estuaries spanned roughly 350 km of the coastline and are nitrogen limited ( Fong and Kennison 2010) (Fig. 1). Summaries for each system can be found in Table 1; for more complete descriptions of each estuary as well as citations for all the characteristics, see Kennison ...
Similar publications
In the highly energetic Columbia River estuary, river discharge and tides are known as dominant factors controlling circulation. In this study, the 3D hydrodynamic unstructured-grid model SELFE is used to investigate the influence of the local wind on salinity intrusion. Numerical simulations are carried out for realistic conditions for the year 20...
Description of fishing gear and operations used in the São Francisco River estuary
Floating bridges over navigable fjords with exposed substructures are at risk of accidental ship collisions. Other hazards such as extreme wind and wave loads are also critical for floating bridges. This study investigates the global dynamic responses of a floating bridge subjected to different combinations of ship collision, wind and wave loads. A...
Abstract The present study aims to estimate effective diahaline turbulent salinity fluxes and diffusivities in numerical model simulations of estuarine scenarios. The underlying method is based on a quantification of salinity mixing per salinity class, which is shown to be twice the turbulent salinity transport across the respective isohaline. Usin...
Citations
... For example, salt marsh burrowing crabs more strongly reduce marsh vegetation cover during droughts . Variability in nutrients, for example due to the fluctuations in precipitation events (Caffrey et al. 2007, Aguilera and Melack 2018, Fong et al. 2020, can create variability in plant nutritional quality (Price 1991, Cronin andHay 1996a, b) and plant responses to animals (Stout et al. 1998, Zhu et al. 2016. ...
Abstract Burrowing animals profoundly influence plant communities, and changes in the burrower and plant communities together with changing abiotic parameters can shift the influence of burrowers on plants. However, we lack an ability to predict when, where, and how burrowers will influence vegetation. To begin to understand how naturally, varying environmental conditions influence the impacts of burrowers, we need to examine how burrower impacts on marsh plants differ across sites differing in environmental conditions. We manipulated crab presence for multiple years and measured the responses of the dominant plants, Pacific cordgrass (Spartina foliosa) and perennial pickleweed (Sarcocornia pacifica), at three sites in northern California and two sites in southern California. Southern California (Point Conception, CA, to the U.S.–Mexico border) experiences higher air and water temperatures, lower precipitation, and higher porewater salinity levels. Combining data from these field studies with laboratory studies allowed us to generate predictions about burrowing crab effects in salt marshes. Our models included (1) an estimate of grazing pressure on marsh plants by the dominant burrowing crab (Pachygrapsus crassipes) and (2) several soil biogeochemical measurements. Crab effects varied from strongly positive to strongly negative and depended upon estimated crab grazing pressure and edaphic conditions (salinity, ammonium, and nitrate). Relative to crabs at other sites, crabs enhanced cordgrass at sites with intermediate levels of ammonium and extreme salinities. The dependence of crab effects on edaphic conditions suggests that projected interannual variability in temperature, precipitation, and nutrients could lead to more temporally variable impacts of crabs on cordgrass. Understanding the environmental controls on these interactions will help promote cordgrass productivity and stabilize salt marsh ecosystems.
To improve the effectiveness of envir onmental management of watersheds and improve the environmental management mechanism of cross-administrative watersheds, we develop a neoliberal framework for action using incentives, examine the cooperative strategies of local governments in watershed treatment and people-oriented environmental protection under central government subsidies, and analyze the cost effectiveness of multiple strategies in a dynamic perspective, and we have the following important findings: (1) Compared to vertical ecological compensation, the introduction of horizontal cost-sharing contracts is more effective in enhancing inter-local cooperative environmental governance. (2) When the marginal benefit of the downstream local government is greater than half of the upstream marginal benefit, the upstream local government’s pollution control investment and the effect of pollution control are improved, and the Pareto improvement of the environmental governance benefit of the watershed is realized, i.e., the cost-sharing contract driven by the downstream can achieve a win–win situation for both environmental and government governance benefits. (3) When the marginal benefit of downstream environmental advocacy is between 0.5 and 1.5 times the marginal benefit of upstream government, the cost-sharing contract is more effective in improving downstream benefits. Conversely, when the marginal benefit of downstream is greater than 1.5 times, the marginal benefit of upstream, the more effective the cost-sharing contract is in improving the marginal benefit of downstream. The results of the study provide useful insights for the government to develop reasonable pollution management cooperation mechanisms to improve environmental management performance and thus enhance the sustainable development of the watershed.
Graphical Abstract
