37 research outputs found
Water quality and planktonic microbial assemblages of isolated wetlands in an agricultural landscape
Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Wetlands 31 (2011): 885-894, doi:10.1007/s13157-011-0203-6.Wetlands provide ecosystem services including flood protection, water quality
enhancement, food chain support, carbon sequestration, and support regional biodiversity.
Wetlands occur in human-altered landscapes, and the ongoing ability of these wetlands to
provide ecosystem services is lacking. Additionally, the apparent lack of connection of some
wetlands, termed geographically isolated, to permanent waters has resulted in little regulatory
recognition. We examined the influence of intensive agriculture on water quality and planktonic
microbial assemblages of intermittently inundated wetlands. We sampled 10 reference and 10
agriculturally altered wetlands in the Gulf Coastal Plain of Georgia. Water quality measures
included pH, alkalinity, dissolved organic carbon, nutrients (nitrate, ammonium, and phosphate),
and filterable solids (dry mass and ash-free dry mass). We measured abundance and relative size
distribution of the planktonic microbial assemblage (< 45 μm) using flow cytometry. Water
quality in agricultural wetlands was characterized by elevated nutrients, pH, and suspended
solids. Autotrophic microbial cells were largely absent from both wetland types. Heterotrophic microbial abundance was influenced by nutrients and suspended matter concentration.
Agriculture caused changes in microbial assemblages forming the base of wetland food webs.
Yet, these wetlands potentially support important ecological services in a highly altered
landscape.Funding was provided by the Joseph W.
Jones Ecological Research Center.2012-07-2
A Social Identity Approach to Sport Psychology: Principles, Practice, and Prospects.
Drawing on social identity theory and self-categorization theory, we outline an approach to sport psychology that understands groups not simply as features of sporting contexts but rather as elements that can be, and often are, incorporated into a person's sense of self and, through this, become powerful determinants of their sport-related behavior. The underpinnings of this social identity approach are outlined, and four key lessons for sport that are indicative of the analytical and practical power of the approach are presented. These suggest that social identity is the basis for sports group (1) behavior, (2) formation and development, (3) support and stress appraisal, and (4) leadership. Building on recent developments within sport science, we outline an agenda for future research by identifying a range of topics to which the social identity approach could fruitfully contribute