Northern Prairie Wildlife Research Center
Riparian ecosystem creation/restoration techniques are the topic of the largest percentage of the records (46%, STUDY.TYPE, Table 1), followed by case studies, overviews, comparative studies of several cases or a comparison with a control or undisturbed riparian ecosystem, and articles discussing riparian ecosystem creation/restoration programs or plans.
Providing fish and wildlife habitat was the objective of 36% of the records, followed by improving hydrologic flow, erosion control, and water quality (OBJECTIVE, Table 1). Experimental studies compose 16% of the records. A "GENERAL" code was given to about half the records, indicating that the objective of riparian creation or restoration was not stated or was a general effort to mitigate for an impact, such as highway or reservoir construction. Twelve percent of the records were coded "INCIDENTAL" and included information such as natural riparian succession.
Principal techniques discussed in the records are planting, landforming, and seeding (ACTION, Table 1); bank stabilizing, altering hydrologic flow, treating soil, fertilizing, and mowing or clearing were used less often. Stocking (fish or beaver), burning vegetation, and using herbicides or pesticides were mentioned in less than 10% of the records. Seventeen percent of the records discuss spoil materials, and 15% deal with contaminated water or soil (including mining, agricultural, and wastewater).
Wetland vegetation classes (WET.TYPE, Table 1) discussed in the records included palustrine forested (PO-FO), scrub-shrub (PO-SS), emergent (PO-EM), and aquatic beds (PO-AB), and riverine nonpersistent emergent (R-EM2) and aquatic beds (R-AB). Over 150 plant genera were included in the records, with Salix, Populus, Quercus, and Acer most frequently mentioned (47%, 34%, 24%, and 18%, respectively).
About 48% of the records did not state the riverine subsystem involved in the study or overview. Of the records that did specify riverine subsystem, lower perennial (R2) was the most discussed, followed by upper perennial (R3), intermittent (R4), and tidal (R1) (Table 1). Unconsolidated bottoms (UB), shores (US), or streambeds (SB) were discussed in 22% of the records.
Half of the 92 records stated a length of time for the investigation of a riparian site or system, and these varied from 1 to 13 years. About half of the records stating length of investigation presented data from 1 to 2 years of study; less than 10% had data from 8 or more years of study.
Fifty-three percent of the records provided quantitative results of responses to riparian ecosystem creation/restoration efforts. Often, qualitative responses consisted of only a list of species using the area or a general statement that erosion was reduced, hydrologic flow increased, water quality improved, and so forth.
Vegetation was the primary response investigated and discussed in the records (RESPONSE, Table 1). Animal response consisted of fish (22% of the records), nongame birds (16%), waterfowl (14%), shorebirds--including wading birds and seabirds (12%), aquatic invertebrates (14%), mammals (14%), reptiles (7%), and amphibians (4%). Hydrology was discussed in more articles than either water quality or soil properties.
Some discussion of economics was included in about 22% of the records (RESPONSE, Table 1). Records were coded "ECON" if they presented costs involved in creation or restoration planning, techniques, or construction, or discussed cost: benefit ratios. Only 23% of the articles on riparian ecosystems in the WCR Data Base attempted to discuss or evaluate the success of riparian ecosystem creation/restoration efforts (RESPONSE, Table 1).