scholarly journals Salt Marsh Claviceps purpurea in Native and Invaded Spartina Marshes in Northern California

Plant Disease ◽  
2007 ◽  
Vol 91 (4) ◽  
pp. 380-386 ◽  
Author(s):  
A. J. Fisher ◽  
J. M. DiTomaso ◽  
T. R. Gordon ◽  
B. J. Aegerter ◽  
D. R. Ayres

The fungal pathogen Claviceps purpurea (subgroup G3) has a worldwide distribution on salt marsh Spartina spp. In Northern California (United States), native Spartina foliosa sustains high rates of infection by G3 C. purpurea in marshes north of the San Francisco Estuary. Invasive populations of S. alterniflora and S. alterniflora × foliosa hybrids are virtually disease free in the same estuary, although S. alterniflora is host to G3 C. purpurea in its native range (Atlantic Coast of the United States). Greenhouse inoculation experiments showed no differences in susceptibility among S. foliosa, S. alterniflora, and Spartina hybrids. Under field conditions, S. foliosa sustained a higher incidence of disease in coastal marshes than in marshes within the bay. This geographic effect may be attributable to environmental differences between the coast and the bay proper, with the former being more conducive to infection by C. purpurea. Seed set of S. foliosa spikelets was 40 to 70% lower on infected than on uninfected inflorescences, but seed germination was not affected. The C. purpurea epidemic on S. foliosa on the coast north of the San Francisco Estuary further reduces the meager competitive ability of this declining native plant species.

2018 ◽  
Vol 9 (1) ◽  
pp. 246-254 ◽  
Author(s):  
Joseph E. Kirsch ◽  
Richard F. Feeney ◽  
Alisha Goodbla ◽  
Christopher Hart ◽  
Zachary J. Jackson ◽  
...  

Abstract Exotic species have been implicated as a major threat to native freshwater fish communities in the Unites States. The San Francisco Estuary watershed has been recognized as one of the most invaded systems where exotics often dominate the fish community. On October 6, 2014, members of the U.S. Fish and Wildlife Service detected a previously unknown exotic fish in a disconnected pool immediately upstream from the Chowchilla Bifurcation Structure in the San Joaquin River, a major tributary of the San Francisco Estuary. A member of the U.S. Fish and Wildlife Service initially identified the fish as an Oriental Weatherfish Misgurnus anguillicaudatus using external morphological characteristics. We conducted additional fish sampling near the Chowchilla Bifurcation Structure in November 2014 and collected a total of six additional specimens in disconnected pool habitats. Unexpectedly, genetic and meristic techniques revealed that these specimens were Large-Scale Loach Paramisgurnus dabryanus. To our knowledge this is the first confirmed occurrence of Large-Scale Loach in the United States and the suspected pathway of introduction is release from aquaria. Very little is known about the population in the San Joaquin River. We recommend further evaluation of the ecology, distribution, and abundance of Large-Scale Loach to better understand their potential impact on the fish communities of the San Joaquin River and the likelihood of establishment throughout the United States.


Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 362
Author(s):  
Margaret A. Christie ◽  
Christopher E. Bernhardt ◽  
Andrew C. Parnell ◽  
Timothy A. Shaw ◽  
Nicole S. Khan ◽  
...  

Building robust age–depth models to understand climatic and geologic histories from coastal sedimentary archives often requires composite chronologies consisting of multi-proxy age markers. Pollen chronohorizons derived from a known change in vegetation are important for age–depth models, especially those with other sparse or imprecise age markers. However, the accuracy of pollen chronohorizons compared to other age markers and the impact of pollen chronohorizons on the precision of age–depth models, particularly in salt marsh environments, is poorly understood. Here, we combine new and published pollen data from eight coastal wetlands (salt marshes and mangroves) along the Atlantic Coast of the United States (U.S.) from Florida to Connecticut to define the age and uncertainty of 17 pollen chronohorizons. We found that 13 out of 17 pollen chronohorizons were consistent when compared to other age markers (radiocarbon, radionuclide 137Cs and pollution markers). Inconsistencies were likely related to the hyperlocality of pollen chronohorizons, mixing of salt marsh sediment, reworking of pollen from nearby tidal flats, misidentification of pollen signals, and inaccuracies in or misinterpretation of other age markers. Additionally, in a total of 24 models, including one or more pollen chronohorizons, increased precision (up to 41 years) or no change was found in 18 models.


2020 ◽  
Vol 20 (2) ◽  
pp. 45-54
Author(s):  
Samuel H. Yamashita

In the 1970s, Japanese cooks began to appear in the kitchens of nouvelle cuisine chefs in France for further training, with scores more arriving in the next decades. Paul Bocuse, Alain Chapel, Joël Robuchon, and other leading French chefs started visiting Japan to teach, cook, and sample Japanese cuisine, and ten of them eventually opened restaurants there. In the 1980s and 1990s, these chefs' frequent visits to Japan and the steady flow of Japanese stagiaires to French restaurants in Europe and the United States encouraged a series of changes that I am calling the “Japanese turn,” which found chefs at fine-dining establishments in Los Angeles, New York City, and later the San Francisco Bay Area using an ever-widening array of Japanese ingredients, employing Japanese culinary techniques, and adding Japanese dishes to their menus. By the second decade of the twenty-first century, the wide acceptance of not only Japanese ingredients and techniques but also concepts like umami (savory tastiness) and shun (seasonality) suggest that Japanese cuisine is now well known to many American chefs.


2021 ◽  
pp. 1-24
Author(s):  
Chad F. Hammer ◽  
John S. Gunn

Abstract Non-native invasive plant species are a major cause of ecosystem degradation and impairment of ecosystem service benefits in the United States. Forested riparian areas provide many ecosystem service benefits and are vital to maintaining water quality of streams and rivers. These systems are also vulnerable to natural disturbances and invasion by non-native plants. We assessed whether planting native trees on disturbed riparian sites may increase biotic resistance to invasive plant establishment in central Vermont in the northeastern United States. The density (stems/m2) of invasive stems was higher in non-planted sites (x̄=4.1 stems/m2) compared to planted sites (x̄=1.3 stems/m2). More than 90% of the invasive plants were Japanese knotweed (Fallopia japonica). There were no significant differences in total stem density of native vegetation between planted and non-planted sites. Other measured response variables such as native tree regeneration, species diversity, soil properties and soil function showed no significant differences or trends in the paired riparian study sites. The results of this case study indicate that tree planting in disturbed riparian forest areas may assist conservation efforts by minimizing the risk of invasive plant colonization.


2020 ◽  
pp. 089692052098012
Author(s):  
Els de Graauw ◽  
Shannon Gleeson

National labor unions in the United States have formally supported undocumented immigrants since 2000. However, drawing on 69 interviews conducted between 2012 and 2016 with union and immigrant rights leaders, this article offers a locally grounded account of how union solidarity with undocumented immigrants has varied notably across the country. We explore how unions in San Francisco and Houston have engaged with Obama-era immigration initiatives that provided historic relief to some undocumented immigrants. We find that San Francisco’s progressive political context and dense infrastructure of immigrant organizations have enabled the city’s historically powerful unions to build deep institutional solidarity with immigrant communities during the Deferred Action for Childhood Arrivals (DACA [2012]) and Deferred Action for Parents of Americans (DAPA [2014]) programs. Meanwhile, Houston’s politically divided context and much sparser infrastructure of immigrant organizations made it necessary for the city’s historically weaker unions to build solidarity with immigrant communities through more disparate channels.


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