River & Watershed Management

River & Watershed Management - Lecture 20- River and...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
Lecture 20- River and Watershed Management Freshwate r Ecosyste ms EVPP/BIO Source lecture material: River Ecology and Management: Lessons from the Pacific Coastal Ecoregion. 1998. Naiman, R. J. and R. E. Bilby (eds). Springer-
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Environmental change During the past two centuries, human activities have become the principal driver of change on earth Human-caused change may be positive, neutral or negative Resource and environmental managers want to detect and treat changes that have negative consequences; they also want to avoid wasting resources
Background image of page 2
Environmental Health of Rivers Changes anywhere on the landscape are likely to influence rivers Examples are: - Harvesting forests - Constructing flood control measures - Mining for minerals - Constructing industrial parks, shopping centers, homes and roads - Converting land for agriculture
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Biological Integrity of Rivers Biological integrity is the capacity to support and maintain a balanced, integrated, and adaptive biological system having the full range of elements and processes expected in a region’s natural habitat
Background image of page 4
Human impact When humans modify landscapes or stream channels, changes in biological integrity are likely Human actions can jeopardize the biological integrity by altering one or more principle factors: - physical habitat - seasonal flow of water (hydroperiod) - the food base of the system
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Disturbances Systems possessing biological integrity can withstand, or recover rapidly from, most natural disturbances Biological integrity declines if the natural disturbance regime is altered by perturbation that lies outside the biota’s adaptive experience Especially when disturbances become incessant
Background image of page 6
Disturbances
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Biological monitoring Biological monitoring is the most practical and cost-effective approach to determine if human actions are degrading biological integrity Four major measurement approaches commonly used to detect the effects of human actions: - Indicator taxa or guilds - Species richness, diversity and evenness - Multivariate statistics - Multimetric indices such as IBI’s
Background image of page 8
Sampling design Compared with physical or chemical parameters, biological parameters have a high natural variability (‘noise’) Statistics are very important when interpreting biological data Just comparing an impacted area with a control area (or one area before and after impact) is not enough A BACI-design (and improvements on this
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 10
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 01/23/2012 for the course BIOL/EVPP 350 taught by Professor Kimdemutsert during the Fall '11 term at George Mason.

Page1 / 38

River & Watershed Management - Lecture 20- River and...

This preview shows document pages 1 - 10. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online