There was some confusion about the discussion for next week. Valerie and Yaw signed up for papers that had been crossed off the list. Please pick one of the other six papers to read instead. If you are unable to find the papers you signed up for please email me (bostby@vt.edu) and I will send you the pdf. Here is list:
Kaushal, S. S. et al (2008)--Jeremy
Christian, A. D., B. G. Crump, and D. J. Berg. 2008. Nutrient release and ecological stoichiometry of freshwater mussels (Mollusca: Unionidae) in 2 small regionally distinct streams. Journal of the North American Benthological Society 27(2): 440-450.--Jane
Merz, J. E. and P. B. Moyle. 2006. Salmon, wildlife, and wine: marine-derived nutrients in human-dominated ecosystems of central California. Ecological Applications 16(3): 999-1009.--Matt
Wipfli, M. S., J. S. Richardson, and R. J. Naiman. 2007. Ecological linkages between headwatersand downstream ecosystems: transport of organic matter, invertebrates, and wood down headwater channels. Journal of the American Water Resources Association 43(1): 72-85.--Ryan
James, L. A. H., Xeonpoulos, J. F. Wilson, and P. C. Frost. 2007. Land use controls nutrient excretion by stream invertebrates along a gradient of agriculture. Journal of the North American Benthological Society 26(3): 523-531.--Lee
C. C. Vaughn, S. J. Nichols, and D. E. Spooner. 2008. Community and foodweb ecology of freshwater mussels. Journal of the North American Benthological Society 27(2): 409-423.--Brandon
Subscribe to:
Post Comments (Atom)
4 comments:
these papers are all posted on Blackboard
James et al. (2007), in their journal paper ‘Land use controls nutrient excretion by stream invertebrates along a gradient of agriculture’, assert that agricultural land use in the watersheds of streams affects mass-specific excretion rates of N and P by mayflies. They support this assertion by measuring mayfly excretion rates and molar ratios of dissolved organic C (DOC), NH4, and soluble reactive P (SRP) in six streams flowing through watersheds with contrasting agricultural land use. The authors accept the fact that they do not know whether ambient environmental factors, such as temperature, or other metabolic predictors such as body mass or larval instar can explain the variable release ratios observed in their study. The main purpose of James et al is to add to the dearth of knowledge on the relationships between nutrient ratios in food and consumer release ratios in streams flowing through heterogeneous landscapes.
James L. A. H., M. A. Xenopoulos, H. F. Wilson and P. C. Frost(2007). Land use Controls Nutrient Excretion by Stream Invertebrates along a Gradient of Agriculture, J. N. Am. Benthol. Soc., 26(3):523–531.
In their journal paper ‘Where Have All the Fish Gone: The reasons why fish catches in Swiss Rivers are Declining’, Burkhardt-Holm et al (2005) propose a multi-factor cause to the vanishing stocks of fish in Swiss streams and rivers. They support this assertion by employing two approaches: development of a Bayesian probability network to summarize the qualitative and quantitative information to study the manifold interrelations among the various factors; and the weight-of-evidence analysis approach, which aims at evaluating the available evidence as objectively as possible. Before the authors propose remediation strategies, they advice that any proposed measure must clearly be adapted to local conditions, because of space limitations. Burkhardt-Holm et al (2005) aim to demonstrate the extent to which anthropogenic factors impact on stream and river fish stocks.
Burkhardt-Holm P., H. Güttinger, U. Ochsenbein, A. Peter, K. Scheurer, H. Segner, E. Staub, M. J.-F. Suter (2005). Where Have All the Fish Gone: The reasons why fish catches in Swiss Rivers are Declining, Environmental Science & Technology 441–447.
Wipfli, Mark S., “Ecological Linkages Between Headwaters and Downstream Ecosystems: Transport of Organic Matter, Invertebrates, and Wood Down Headwaters Channels.” (2007) asserts that headwater streams make up a large proportion of the total watershed area as well as supply vital necessities to downstream organisms, but the quality of these materials as it affects biological activity downstream is not well known. Wipfli explains the numerous processes that take place to ensure that the down water reaches of a watershed will be supplied with the proper essentials required to thrive, but he doesn’t present any data explanation or challenge the hypothesis to back up his points, which are already widely accepted. In order to better explain the necessity of headwaters to larger order rivers, the author suggests three main reasons for why the headwater streams could be important to the ecological integrity of downstream reaches: 1. headwater habitats encompass over 80% of stream networks and watershed land areas 2. they are closely tied spatially to larger streams entering at numerous contact points 3. the water draining from headwater streams provide a continuous resource for essential nutrients, food, and wood, which support life in the larger order rivers. This article could be of most use to managers and authorities that have control of waterways and watersheds and may otherwise not fully understand the importance of headwater streams with regards to larger order rivers.
Post a Comment