This is the first question to ask in any planning project. Not until we can describe in a convincing story line where our stream habitat is there is no hope for moving on to the next phase of Where do we want to go ? or How will we get there?
This semester our discussions thus far have addressed the fourth planning question "Did We Make It?" and you now have an interesting global or national perspective on the success of stream restoration.
This week our discussion will focus on smaller-scale case studies where you can really critique the "leitbild" and the study design, data collection methods and or assumptions.
I just finished reading an interesting story about restoring apache trout in Arizona -- in this case the invasive trouts are the number one limiting factor and instream barriers are being managed to prevent their encroaching. Sometimes the habitat is adequate but other constraints must be overcome.
I am very optimistic about the progress of stream rehabilitation and it comes from little stories that I hear about that indicate that we are better off than we were decades ago. In Ohio for instance they recently recognized that what people have been calling ditches during their lifetimes are really part of the flowing waters of the state and need to be monitoring and protected just as the 'rivers' are. Take a look at the article entitled: Ditch? Stream? Name matters
I will introduce the concept and methods of Habitat Assessment (aka habitat evaluation or biophysical condition assessment). There are many variations on the theme which range from the Rapid to the Gradual to the Glacial time frames. You can review the Rapid methods that Virgina volunteers currently use. Click here! Scan some paper on riffle stability index by kapesser and the see if you can use the Habitat Assessment Form on your 'favorite' creek.
Click on COMMENT below and post your rhetorical precis here.
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As our first speaker's topic of adding limestone to acid-impaired streams sparked some interesting discussion, I decided to find a case about that:
McClurg , S. E., J. T. Petty, P. M. Mazik, and J. L. Clayton. 2007. Stream ecosystem response to limestone treatment in acid impacted watersheds of the Allegheny Plateau. Ecological Applications. 17: 1087-1104.
The authors begin by describing that streams in the Allegheny Plateau, WV, USA have been impacted by episodic acidification, and that the ensuing high levels of inorganic Al and low pH have restructured the biota. They briefly mention the evolution of limestone application to acidified streams, and posit that biological evaluations of pH buffering strategies have been lacking. They studied 8 streams with circumneutral pH, 8 acidic streams that have been historically treated with limestone, and 4 acidic streams that have not been treated (N=20). All streams had relatively good in-stream habitat (based on EPA RHVA protocols). They took seasonal water quality measurements (pH and pH-related ions). They sampled biofilm the spring and summer, and invertebrates and fishes in spring. They found that, despite wide seasonal variability, limestone-treated streams had higher pH and lower toxic ion concentrations (such as free Al). They found that stream status (impaired, not impaired) had no effect on biofilm biomass. They found that stream status had a significant effect on all benthic macroinvertebrate metrics effect community metrics (taxa richness, density, taxa-tolerant biomass, etc…), and that the community metrics of acidic streams were often indistinguishable between acidic and circumneutral streams. Stream status significantly affected 5 of 7 fish community metrics, despite high variability. Fish community metrics were highly correlated with basin area, but small treated streams were more similar to large circumneutral streams. They also found that the amount of time after application (in the perspective of ca. 35 years) had no effect on biota, suggesting somewhat instantaneous recovery (ca. 2 years). They deem the non-recovery of invertebrates and recovery of fishes and “incomplete recovery”, and describe its ubiquitousness in acidic stream restoration. They conclude that, in terms of brook trout biomass and YOY density, limestone treatments of acidic streams can be considered successful. As many of our readings conclude, they also place emphasis on the need for biological monitoring to assess the effectiveness of restoration projects.
In the article “Long-term effect of instream habitat-improvement structures of channel morphology along the Blackledge and Salmon Rivers, Connecticut, USA”, Thompson examines the effectiveness of 40 in-stream structures constructed in two American rivers during the 1930’s and 1950’s. He measured each structure’s effectiveness according to current understand of what constitutes adequate aquatic habitat and points out that although some structures successfully increased aquatic habitat, most of the habitat created is marginal at best. The creation of marginal habitat and destruction of habitat caused by the failures of some structures lead the author to question the worth of attempting to modify channel morphology through these methods; considering many modern restoration guidelines have not changed since these structures were designed. The purpose of this article is to urge stream managers to consider stream “restoration” impacts beyond the typical 20 y period to prevent future managers from having to restore channels destroyed by previous restoration efforts.
Thompson, D. M., 2002. “Long-term effect of instream habitat-improvement structures on channel morphology along the Blackledge and Salmon Rivers, Connecticut, USA.” Environmental Management. 29: 250-265
Champoux, O., P. M. Biron, A. G. Roy. 2003. The long-term effectiveness of fish habitat restoration practices: Lawrence Creek, Wisconsin. Annals of the Association of American Geographers 93(1): 42-54.
In “The long-term effectiveness of fish habitat restoration practices: Lawerence Creek, Wisconsin,” Champoux et al. revisit a central Wisconsin stream restoration project where bank-cover deflectors were installed in 1963 to decrease stream width and create pools to benefit native brook trout. They resurveyed the creek in 1999 and compared geomorphology and physical habitat to surveys conducted prior to restoration and just after restoration. They found that the restoration project had long lasting positive consequences for instream habitat; however, success was tempered by underlying glacier geology. This case study demonstrates the importance of long-term monitoring and how factors working at larger scales can influence the success of local habitat restoration.
Kappesser, G. B. 2002. A riffle stability index to evaluate sediment loading to streams. Journal of the American Water Resources Association 38(4): 1069-1081.
In “A riffle stability index to evaluate sediment loading to streams,” Kappesser introduces and defines the Riffle Stability Index (RSI) as a point estimate of sediment transport in a stream (or more specifically an estimate of deviation from dynamic equilibrium). To obtain an RSI, dominant particle size on an exposed bar proximate to a riffle is compared to a particle -size distribution curve developed from that riffle; the RSI is the percent of particle sizes in the riffle smaller than the dominant bar substrate size. Kappessar explores the variation inherent to the RSI, how the RSI varies between disturbed and less disturbed or reference streams, and also how the RSI compares to other techniques to measure sediment transport. Kappessar demonstrates that the RSI is an adequate point estimate for sediment transport processes that take place over larger spatial and temporal scales.
Binns (2004) examined pre-treatment and post-treatment data from 30 state agency executed habitat improvement projects to understand the amount of success these types of projects have on wild salmonid populations in Wyoming. He monitored trout abundance and biomass to gage success and found that most habitat improvement projects, with a few notable exceptions, were effective at increasing trout production. Moreover, he found that the instreram structures were durable, with most lasting the duration of the study. Binns also monitored the cost of each project, reporting that the average project costs around 39 thousand dollars and that projects on larger streams cost considerably more than projects on smaller streams. Binns purpose is to synthesize data on the success and failure of current habitat improvement projects to help guide further such projects in the future. He concludes his paper with seven guidelines for habitat improvement, including continued maintenance of structures and building structures that do not impede water during flood conditions.
Binns, N.A. 2003. Effectiveness of habitat manipulation for wild salmonids in Wyoming streams. North American Journal of Fisheries Management 24:911-921.
Kappesser (2002) introduces the Riffle Stability Index (RSI) as a standardized way of quantitatively measuring channel type response to increased sediment loads. He uses field data, including Rosgen’s classification of stream channel, pebble counts to determine particle size distribution, and measurements of freshly moved particles, from Idaho and Virginia to establish the RSI. The RSI appeared to be a sensitive indicator of land use and stream management practices as well as natural processes in the Idaho and Virginia datasets. The purpose of this paper is to provide researchers and managers alike with a tool for measuring the effects of sediment input on streambeds. The RSI provides a common language and a useful way of quantifying sedimentation.
Kappesser, G.B. 2002. A riffle stability index to evaluate sediment loading to streams. Journal of the American Water Resources Association 38:1069-1081.
Leah D. Carlson and Michael S. Quinn, “Evaluating the Effectiveness of Instream Habitat Structures for Overwintering Stream Salmonids: A Test of Underwater Video” (2005) insists that human-fabricated instream structures are designed with summer conditions in mind and pay little attention to the structures’ function under winter conditions. This article states that more information needs to be gathered about the effectiveness of these instream structures in winter periods, but that typical fish sampling techniques that cannot be implemented in the winter, especially with regards to ice-covered sections of a stream. Carlson and Quinn present the sampling and observation technique of using under-water video to monitor where the fish are and how many are in certain areas in order to tell whether these artificial instream structures are adequate in providing for the needs of salmonids during the winter months. This article is intended to be used by anyone who may be curious about the functionality of instream structures, as well as people who are attempting to discover new forms of fish sampling and monitoring.
In “Restoring stream ecosystems: lessons from a Midwestern state” by Moerke and Lamberti 2004, the authors address 10 stream restorations at the reach scale to assess conditions based on habitat, water quality, and questionnaires in restored and unrestored reaches. The streams chosen for this assessment were chosen from a set of pre-determined metrics. Stream restorations varied greatly in cost, with private clients having a higher cost on average than public works. Moerke and Lamberti broke the clientele into 3 categories, encompassing government, private, and nongovernmental organizations as the sources of the restorations. The study found that 30% of the restorations were permit driven, while 40% were concerned with aesthetics and 50% were environmentally centered. Goals of the restorations were unclear at times, with ecological improvement as a motivating factor. Riparian zones predominated ecological restoration efforts, with much less emphasis put on stream biota. Historical, ecological, and engineering factors were incorporated into only 50% of the projects surveyed. Amount of techniques used to restore streams varied greatly, but the restorations shared common factors, such as greater than 70% improved terrestrial and aquatic habitat, channel morphology, and bank conditions. Monitoring occurred in 30% of the sites pre-restoration, 50% post-restoration, and 30% pre and post restoration. The main point of this article is to show efficiencies and deficiencies in Indiana in-stream and riparian habitat restoration and management, which is useful to project leaders and managers in the Midwest and on a broader scale.
Moerke, A.H., and G.A. Lamberti. 2004. Restoring stream ecosystems: lessons from a Midwestern state. Restoration Ecology 12(3): 327-334.
Kappesser, in his article “A riffle stability index to evaluate sediment loading to streams” argues that the relative amount of sediment entering a stream segment relative to the amount leaving a stream reach can be quantified into a riffle stability index (RSI) and can then be used as an index of stream reach condition and habitat quality for in-stream biota. The author used sediment particle sizes from riffle in streams in Idaho and Virginia with varying levels of watershed impacts to calculate RSI, and then compared these values between the two watersheds as well as to other metrics including pool depth, relative bed stability and relative fish abundances in Idaho streams. The author sees RSI as an easy measure of stream condition, though he admits that large (20%) differences in calculated sediment diameter sizes do not affect the RSI, and that differences in sediment types with varying erosional qualities affect the appropriateness of the RSI method across watersheds. The main purpose of this article is to examine the effectiveness of RSI to other metrics as a method of evaluating sediment loading to stream.
Kappesser, G.B. 2002. A riffle stability index to evaluate sediment loading to streams. Journal of the American Water Resources Association 38(4):1069-1081.
In their research paper, ‘Ecological Success in Stream Restoration: Case Studies from the Midwestern United States’, Alexander and Allan (2006) assert that despite rapid growth in river restoration, few projects receive the necessary evaluation and reporting to determining their success or failure and to learn from experience. They do this after interviewing thirty-nine project contacts from a database of 1,345 restoration projects Ohio, combining responses with project information, and then making comparisons to the criteria set out by Palmer et al. (2005). The writers appear very confident due to the efficient sampling design they employed. Alexander and Allan (2006) are seeking to stress the need to improve several aspects of stream restoration, especially monitoring and the evaluation of project success.
Alexander G. G. and J. David Allan, 2006. Ecological Success in Stream Restoration: Case Studies from the Midwestern United States. Environ Manage (2007) 40:245–255
DOI 10.1007/s00267-006-0064-6
In their paper “River rehabilitation and fish populations: assessing the benefit of instream structures,” Pretty et al. discuss the effectiveness of small instream structures in lowland rivers in England, and they suggest that the structures do not adequately improve streams to observe changes in abundances or richness in rehabilitated reaches and that side channel or backwater habitat improvements may be more effective rehabilitation schemes for this type of stream. The authors sampled thirteen streams that had instream structures installed between 1992-1997 to estimate fish abundance and richness, as well as flow and depth heterogeneity and compared these sites with control reaches within the same streams but outside the reach affected by the structures. The authors believe they can assess the success of these structures from a single year of sampling despite logistical problems (lack of access, large variation in qualitative and quantitative fish data across sites) and they believe the structures do not consistently rehabilitate lowland streams with other water quality and geomorphic disturbances. The authors’ primary goal was to assess if techniques used for higher gradient rivers should be applied in rehabilitation projects whose goals are improvement of fish diversity and abundances in lowland rivers and streams.
Pretty, J.L., S.S.C. Harrison, D.J. Shepherd, and C. Smith. 2003. River rehabilitation and fish populations: assessing the benefit of instream structures. Journal of Applied Ecology 40:251-265.
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