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LENTIC GEOMORPHOLOGY
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LENTIC ASSESSMENT FORM GEOMORPHOLOGY
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16: Accumulation of chemicals affecting plant productivity and composition is not apparent
Yes Item 16. Accumulation of chemicals affecting plant productivity/composition is not apparent. YES it is not apparent – The riparian-wetland vegetation shows no signs of being stressed by an accumulation of chemicals.
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No Item 16. Are the accumulation of chemicals affecting plant productivity and composition not apparent? NO – This accumulation is affecting plant productivity and/or composition. If there is accumulation of chemicals, the ID team must then determine if the accumulation is affecting productivity/composition of riparian-wetland plants. If this accumulation of chemicals is not affecting plant productivity or composition, the answer to item 16 would still be “yes.” There are situations where the accumulation of chemicals is obviously harmful to vegetation, even to the point of being toxic (in some situations, potentially a health hazard to people). An excellent example would be the established Superfund site near Butte, Montana. The heavy metal content in the water of this area has essentially created such harsh conditions in the riparian-wetland area that no vegetation except a few scattered plants can survive. Flocculated metal salts contained in the water may be deposited on the soil surface. The answer in this situation would be “no.” “N/A” would apply for those riparian-wetland areas that do not require vegetation to function properly. 16: Accumulation of chemicals affecting plant productivity and composition is not apparent
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1/18/2019 17. Saturation of soils (i.e. ponding, flooding frequency, and duration) is sufficient to compose and maintain hydric soils. An example of assessing potential of a riparian area onsite might be an examination of the surface soil. This soil is examined for soil features characteristic of anaerobic soil conditions caused by soil saturation. This field examination is often necessary to evaluate question number 1 of the checklist. Given the evidence provided in the picture this question would be answered with a “Yes”.
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18: Underlying geologic structure/soil material/permafrost is capable of restricting water percolation Wetlands often have an underlying clay or rock material that causes sites to persist. Purpose: The intent is to determine whether the underlying material is being maintained. Item 18: Underlying geologic structure/soil material/permafrost is capable of restricting water percolation Purpose The intent of item 18 is to identify whether this underlying material is being maintained. Lentic or standing water riparian-wetland areas often have an underlying material that causes a site to persist. This underlying material restricts water percolation, producing permanent or seasonal ponding, saturation, or inundation. This material may be a geologic structure such as bedrock, a soil type like clay, or permafrost. This underlying material has to be maintained for an area to function properly. The best way to describe the importance of maintaining this underlying material is to compare a riparian-wetland area to a bathtub with a plug. As long as the plug stays in place, the tub can retain water, but as soon as the plug is pulled, it can no longer retain water. When this happens, an area can no longer maintain existing hydrology and associated vegetation because it is being drained and will eventually be lost.
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1/18/2019 18: Underlying geologic structure/soil material/permafrost is capable of restricting water percolation Physically maintaining the water where it can sustain the habitats is most important. If the water is lost through a hole in the floor, such as breaking through a consolidated clay layer, a hole in the wall, such as a hole in the dam, or an incision or gully. The whole system is no longer functional. Vegetation, land form, and the water needed to sustain them creates proper functioning systems or not.
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19: Riparian-wetland is in balance with water and sediment being supplied by the watershed (i.e., no excessive erosion or deposition) Rye Patch Reservoir filling with sediment Purpose The intent of item 19 is to identify that water and sediment are being supplied at a natural rate and can function properly. No
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Yes If a wetland shows no evidence of excessive deposition
If a lentic riparian-wetland area shows no evidence of excessive deposition and is not filling any faster than its normal rate as a result of excess sediment from the watershed, the answer to item 19 would be “yes.” If a wetland shows no evidence of excessive deposition and is not filling any faster than its normal rate, as a result of excess water or sediment from the watershed, the answer would be “yes.”
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20: Islands and shoreline characteristics (i. e
20: Islands and shoreline characteristics (i.e., rocks, coarse and/or large woody material) are adequate to dissipate wind and wave event energies Purpose: To determine the shoreline stability of only those systems that do not require live vegetation. Yes Loss of shorelines affect wetlands by lowering water quality, reducing the capacity to hold water, and altering the plant community. Item 20: Islands and shoreline characteristics (i.e., rocks, coarse and/or large woody material) are adequate to dissipate wind and wave event energies Purpose The intent of item 20 is to address those systems that do not require vegetation. Riparian-wetland areas with islands and shorelines have to be able to dissipate energy during wind action and wave action events to function properly. These islands and shorelines need characteristics that create forces resistant to wind action and wave action. While most lentic riparian-wetland areas require riparian-wetland vegetation along islands and shorelines to do this, some do not. The presence of rocks and/or woody material can dissipate energies associated with wind action and wave action, thereby providing the elements necessary for a system to function properly. Loss of shorelines affects lentic areas by: 1) Lowering water quality 2) Reducing the capacity to hold water 3) Altering the plant community.
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Summary determination
Apparent Monitored ___ Upward ___ Downward ___ Static
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