scholarly journals Physical influences on recruitment to California Current invertebrate populations on multiple scales

2001 ◽  
Vol 58 (5) ◽  
pp. 1081-1091 ◽  
Author(s):  
L Botsford
2020 ◽  
Vol 634 ◽  
pp. 159-173 ◽  
Author(s):  
MC Sabal ◽  
EL Hazen ◽  
SJ Bograd ◽  
RB MacFarlane ◽  
ID Schroeder ◽  
...  

2020 ◽  
Vol 43 (2) ◽  
pp. 9-16
Author(s):  
David N. Pellow

This article offers insights into conceptual, pedagogical, and programmatic crossings and conflicts between the fields of Environmental Studies and Ethnic Studies. It highlights both the important intersections between the two fields and their potential value, while also addressing the challenges posed in the development of programmatic collaborations. Utilizing case studies drawn from the author’s own experiences, the article’s focus is on harnessing the strengths and limitations of both fields to promote transformative knowledge and action at multiple scales.


2019 ◽  
Author(s):  
Michael Stukel ◽  
Thomas Kelly

Thorium-234 (234Th) is a powerful tracer of particle dynamics and the biological pump in the surface ocean; however, variability in carbon:thorium ratios of sinking particles adds substantial uncertainty to estimates of organic carbon export. We coupled a mechanistic thorium sorption and desorption model to a one-dimensional particle sinking model that uses realistic particle settling velocity spectra. The model generates estimates of 238U-234Th disequilibrium, particulate organic carbon concentration, and the C:234Th ratio of sinking particles, which are then compared to in situ measurements from quasi-Lagrangian studies conducted on six cruises in the California Current Ecosystem. Broad patterns observed in in situ measurements, including decreasing C:234Th ratios with depth and a strong correlation between sinking C:234Th and the ratio of vertically-integrated particulate organic carbon (POC) to vertically-integrated total water column 234Th, were accurately recovered by models assuming either a power law distribution of sinking speeds or a double log normal distribution of sinking speeds. Simulations suggested that the observed decrease in C:234Th with depth may be driven by preferential remineralization of carbon by particle-attached microbes. However, an alternate model structure featuring complete consumption and/or disaggregation of particles by mesozooplankton (e.g. no preferential remineralization of carbon) was also able to simulate decreasing C:234Th with depth (although the decrease was weaker), driven by 234Th adsorption onto slowly sinking particles. Model results also suggest that during bloom decays C:234Th ratios of sinking particles should be higher than expected (based on contemporaneous water column POC), because high settling velocities minimize carbon remineralization during sinking.


2012 ◽  
Vol 7 (1) ◽  
pp. 27-46 ◽  
Author(s):  
Luisa Veronis

Issues of immigrant political incorporation and transnational politics have drawn increased interest among migration scholars. This paper contributes to debates in this field by examining the role of networks, partnerships and collaborations of immigrant community organizations as mechanisms for immigrant political participation both locally and transnationally. These issues are addressed through an ethnographic study of the Hispanic Development Council, an umbrella advocacy organization representing settlement agencies serving Latin American immigrants in Toronto, Canada. Analysis of HDC’s three sets of networks (at the community, city and transnational levels) from a geographic and relational approach demonstrates the potentials and limits of nonprofit sector partnerships as mechanisms and concrete spaces for immigrant mobilization, empowerment, and social action in a context of neoliberal governance. It is argued that a combination of partnerships with a range of both state and non-state actors and at multiple scales can be significant in enabling nonprofit organizations to advance the interests of immigrant, minority and disadvantaged communities.


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