angora creek cram assessment

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Angora Creek CRAM Assessment

Kevin MorganDr. StevensField MethodsNovember 6, 2014

Table of ContentsAngora Creek Report..............3Riverine Wetlands Scoring...7Areal Map..8Buffer Map9Pictures10References...........11Angora Creek: Basic Information Sheet...12Hope Valley and Grass Lake Assignment25

Introduction:In June of 2007 a horrific wildfire ripped through a pristine area of Lake Tahoe near Angora Lake, Fallen Leaf Lake, Echo Lake and South Lake Tahoe. The fire started along North Upper Truckee Road, which at the time was a densely populated area of homes. The fire scorched over 3,000 acres and burnt down more than 200 homes, 60 commercial structures, and damaged several other buildings in its path. Today all that remains of the fire is a massive open area full of charred Pine trees, and shrubbery. Since the fire was in the heart of the Lake Tahoe water shed the concern of ash and debris getting into the hydrologic systems was a great concern for many. One of the main hydrologic systems that were involved in the Angora Fire was Angora Creek. The creek wound its way through the base of Angora Meadows, but was not directly in contact of the fire. This specific location is known as a riparian wetland. Upon first arrival, the creek looked shallow and very narrow. There were a few beaver dams that allowed for the assumption that this location is slightly in engineered equilibrium. Due to this assumption it can be said that this specific system has healed from this major disturbance. Along with the observations of beaver work, new growth has well been on its way to helping this system heal. The majority of living vegetation that remains after the fire is primarily Jeffery Pine and Bitterbrush. These two plant types were not the only remaining types within the area. There were also several different types of grasses that can be found along the creek. Tufted Hair grass was the most abundant grass type. Outside of the burn area, there were several other types of vegetation such as; Tufted Hair grass, Purple Aster, Alder trees, Salix Lamoni, and Carix Utricularia. With such varying plant diversity, the means for a reliable water source is important.Angora Creek is a long narrow creek that winds its way at the base of Angora meadows and finds its way to the North Upper Truckee River. There are only two possible sources of water that feed into this stream. One being annual rainfall, and the most important source of water for Angora Creek is the Sierra Nevada snowpack. Having a strong source of water is extremely necessary for an area like this to allow for the site to heal itself and for new plant growth. Due to how well new plant growth was occurring, at first glance, the notion can be made that the water quality of Angora Creek very is sufficient. After doing several water tests, the thought of sufficient water quality within the creek, can be supported because of the findings of new plants, and several microorganisms. Five tests were conducted on the water. The five were; pH, dissolved oxygen, electric conductivity, nitrate, and phosphate. The readings for each test are as follow: pH had a reading of 6.4, which is slightly acidic; dissolved oxygen was 3.7 mg/L with a saturation of 33%; electric conductivity read 52.4; nitrate was 25 ppm; and phosphate was less than 20 ppm. With these tests conducted, the conclusion was made that Angora Creek is aligotrphic meaning that it has low nutrient levels and a high quality of water. By having low nutrient levels in the water, the same can be said about the soils of the region.There are three main soils series that can be found in this area, the Tahoe Series, the Marla Series and the Watah Series. All three of these soils are low in nutrients and they all drain very poorly. The Tahoe Series is a deep soil primarily made up of mixed material, mostly andesitic lahar and granodiorite. Marla Series also is a deep soil that is formed in alluvium from primarily weathered granite rock. The Watah soils are also nutrient poor, deep soils that are formed from organic material. The reason these soils pop up could possible be due to the amount of carbon that found its way to the ground after the fire. By being such a disturbed area of land, with the combination of decent soils and good quality of water Angora Creek is a surviving system. Although it is a surviving system, it is still in an area that can over time be exposed to several other types of disturbances.Disturbances can vary from fire (as occurred) to human disturbances such as mountain biking, ATV riding, camping and several other activities that can harm the environment. Angora creek has no visual impacts of disturbances. The only noted disturbance was with in the AA was a small electrical box that was beneath the electrical pole. There were other possible disturbances near the AA like North Upper Truckee Road, the several dozen homes that ran along the road, as well as the small foot/mountain biking path that ran above the AA. None of these disturbances directly impacted Angora Creek. Methods:California Rapid Assessment Method or CRAM is used by field scientists to assess a representative wetland area by using several environmental and habitual aspects. These aspects involve vegetation, topography and hydrology. For the Angora Creek site, Riverine Wetlands CRAM was used, which involves four attributes. Those attributes are; Buffer and Landscape Quality, Hydrology, Physical Structure, and lastly Biotic Structure. Once each attribute is assessed, an alphabetical score (A-D) is given and each alphabetical score has a corresponding numerical value where an A equals 12, B equals 9, C equals 6, and D equals 3. Results:Results for CRAM consist of four scores for each attribute. The scores are made up of the four different alphabetical and numerical scores. Each attribute has a series of tests that field scientist conduct in order to obtain a score. The results for Angora Creek attribute 1 (Buffer and Landscape context) had a score of 93.29. Attribute 2 (Hydrology) had a score of 100, attribute 3 (Physical Structure) had a score of 75 and lastly attribute 4 (Biotic Structure) had a score of 69.43. Once each attributes score is computed, the overall AA score is then conducted, by taking the average of the four attribute scores. The overall AA score for Angora Creek came out to be an 84.43. (Refer to page 7)Discussion:Previously, the same CRAM assessment was done on Angora Creek. The results that the instructor copy came up with were a little lower than what the latest CRAM results showed. The overall AA score of the instructor copy was 82.0, which was only 4 points off of the newest score that was an 86.0. The fact that these two scores are so close is surprising because each CRAM assessment was ran during different season. The lack of rainfall, and the continuous build up of sediment can be the primary reason as to why these two scores are so close. Conclusion:Assessing Angora Creek was an excellent way to really determine how well this location has recovered from this major disturbance. Not only was it a great tool to conclude that Angora Creek has heeled itself from this fire, but it was helpful for me to obtain a better understanding of how to go about conducting a CRAM. The Tahoe Region is a place dear to my heart not only because I am an avid outdoors person, but also it is an area that I have many memories of my childhood. To see such a beautiful landscape destroyed by a fire and then recover so wonderfully is a great way to open my eyes to how important a strong understanding of natures work is.

Riverine Wetlands ScoreAttribute 1: Buffer & Landscape Context

AlphaNumeric

Stream Corridor ContinuityA12

Buffer Submetric: Percent of AA with BufferA12

Buffer Submetric: Average Buffer WidthA12

Buffer Submetric: Buffer ConditionB9

Raw Attribute Score22.59

Final Attribute Score93.29%

Attribute 2: Hydrology

AlphaNumeric

Water SourceA12

Channel StabilityA12

Hydrologic ConnectivityA12

Raw Attribute Score36

Final Attribute Score100%

Attribute 3: Physical Structure

AlphaNumeric

Structural Patch RichnessA12

Topographic ComplexityC6

Raw Attribute Score18

Final Attribute Score75%

Attribute 4: Biotic Structure

AlphaNumeric

Plant Community Submetric: Number of Plant LayersA12

Plant Community Submetric: Co Dominant SpeciesC6

Plant Community Submetric: Percent InvasiveA12

Plant Community Composition Metric10

Horizontal InterspersionB9

Vertical Biotic StructureC6

Raw Attribute Score25

Final Attribute Score69.44%

OVERALL AA SCORE84.43%

Areal Map

Buffer Map

Pictures

ReferencesDwire A, K., Kauffman J. B. Fire and riparian ecosystems in landscapes of the western USA.Forest Ecology and Management. 2003. 178: 61 74Tahoe Riverine CRAM Training Session Field Site #5 Thursday Morning. INSTRUCTORCOPY