Studies of benthic macroinvertebrates for the Shenandoah National Park long-term ecological monitoring system: statistical analysis of LTEMS aquatic dataset from 1986 to 2000 on water chemistry, habitat, and macroinvertebrates

Moeykens, Michael; Voshell, Reese

Analyzes data on benthic macroinvertebrates assemblages that have been collected in SHEN and investigate relationships bewteeen this data and GIS data on physical features, land use, invasive species, natural catastrophes, and resource management practices. In order to have effective monitoring of Shenandoah National Park (SNP), Virginia, NPS personnel began planning the Long-Term Ecological Monitoring System (LTEMS) in 1984. The resulting multifaceted LTEMS includes an aquatic component that focuses on biomonitoring of benthic macroinvertebrates in SNP streams, but also includes other biological, physical, and chemical measurements (Ravlin et al. 1990). Data collection for the aquatic component of the LTEMS began in 1986. Since 1986, 17 core sites have been sampled at least once per year, and in 1995 SNP personnel began to cycle in other sites along with the original 17, with the goal of eventually sampling every permanent stream within park boundaries. The first 6 years of macroinvertebrate data (1986-1992) were analyzed in a previous report (Smith and Voshell 1994), but very little of the physical and chemical data were available in the LTEMS computer database at the time of those statistical analyses. Thus, there have been no comprehensive analyses of the entire LTEMS database on macroinvertebrates and related biological, physical,and chemical measurements. In addition, a standard protocol for analyzing and interpreting the aquatic component of the LTEMS has not been developed. Since the original development of the LTEMS, SNP personnel have incorporated land use information and various other important data related to the LTEMS into a geographical information system (GIS) database. This project was undertaken in response to these data analysis needs and advancements in available information technology at SNP. The overall goals of this project were to analyze the data on benthic macroinvertebrates assemblages that have been collected in SNP as part of the aquatic component of the LTEMS; investigate any relationships between these data and GIS data on physical features, land use, invasive species, natural catastrophes, and resource management practices; and provide SNP with methods for future data analysis. The specific objectives of this project were to: 1) select a suite of metrics that will be effective for long-term biomonitoring of benthic macroinvertebrates in SNP streams; 2) ascertain the ecological condition of streams in SNP as compared to other similar streams in the Blue Ridge ecoregion; 3) determine if the ecological condition of any streams differs within SNP, and, if so, which ones are different and whether the differences are related to any of the likely causative factors in SNP; and 4) if the ecological condition of SNP streams compares favorably with that of streams outside SNP and if the ecological condition of streams is consistent within SNP, decide if the current benthic macroinvertebrate biomonitoring protocol in SNP would be effective at discerning impaired ecological condition if significant pollution or environmental stress did occur in SNP.