EXAM (Total 80 marks)
The Exam is due on Friday, December 4th, 2015 at 11:00 am. This Exam is based on the following reference.
Cummins, K. W. and M. A. Wilzbach. 2009. River and Streams: Ecosystem Dynamics and Integrating Paradigms. Pages 351-362 in S. E. Jorgensen, editor. Ecosystem Ecology. Elsevier.
Part I Word Bank (7 marks)
in stream plant growth Majority heterotrophs
autotrophic Larger rivers omnivorous
detritus Smaller steams carnivorous.
heterotrophic plant growth in the water very few
1. Stream and river ecosystem in which the majority of the energy transfer is from _______________ to consumers are termed__________________________.
2. __________________in forested catchments are usually dominated by litter energy sources. 3. Wider, stream segments are dominated by___________________________.
4. ___________________________are dominated by OM delivered from the upstream tributary network.
5. Feeding studies of benthic invertebrates have shown that, based on food ingested, most taxa are ___________________
6. ___________________ of the stream/river consumers utilize macrophytes, filamentous algae and rooted vascular plants?
Pat II Structure Questions (73 marks)
1. Two energy sources for rivers and streams are sunlight and plant litter from stream side (riparian vegetation. Both of these are inversely related. Discuss this statement. (5 points) 2. Explain the energy models in figure 1 and figure 2, pages 352 and 353 respectively. (5 marks) 3. Explain the nutrient spiraling on recycling on fig 4 (a) and ((d) page 355. What is the difference
between nutrient recycling between a lotic and a lentic ecosystem? (5 marks) 4. Explain briefly why you cannot analyze simple trophic categorization of stream macroinvertebrate
using trophic level analysis. (5 marks)
5. Since trophic level analysis was not an appropriate technique for classification of stream
macroinvertebrate. Therefore, another approach of classification technique was developed. Discuss
this alternate classification technique? (15 marks)
6. As the relative availability of the basic food resources changes, there is an related change in the corresponding ratios of the functional feeding groups (shedders, filtering and gathering collectors, scrapers and predators) of freshwater invertebrates adapted to specific resource categories
(CPOM,FPOM, Periphyton, Prey). Elaborate on this statement (5 marks). 7. State an advantage of the functional feeding group procedure. (3 marks) 8. State the three complex interactions in the transport and storage of Organic material.(3 marks) 9. Several conceptual models have been developed to explain specific components of lotic system
structure and function. List the nine of them and briefly explain their role in the stream/ river
