• 作者： --
• 中文摘要： This study investigated the quantitative relationships between benthic macroinvertebrates and
  stream environmental variables using generalized additive models. The benthic data used in the
  study were collected by the Virginia Department of Environmental Quality from 1994 through 2001.
  The benthic macroinvertebrate assemblages were represented by five benthic metrics namely taxonomic
  richness, proportion of the two most dominant taxa, proportion of sensitive taxa, proportion
  of tolerant taxon, and proportion of shredders. Twenty environmental variables, of which eight
  were physicochemical and twelve were habitat related, represented stream environmental conditions.
  The study findings suggest a sharp decline in taxonomic richness at total suspended solids concentration
  of 9 mg/L to 17 mg/L. At flow rates above 85 cfs, taxonomic richness decreases with increasing
  flow rate. As the dissolved oxygen concentration increases, the proportion of sensitive taxa
  also increases, while the proportion of tolerant taxon and the two most dominant taxa decreases.
  None of the physicochemical variables showed a significant effect on the proportion of shredders.
  Also, the variations of pH within the pH range observed in the case study streams (pH 6 to pH 10)
  had no significant effects on the responses of the benthic metrics. For the habitat variables, taxonomic
  richness and sensitive taxa positively correlated with channel flow status and substrate, respectively.
  Tolerant taxon negatively correlated with substrate.
• 英文摘要： 本研究對水底大型無脊椎動物（Macroinvertebrates 或MI）與河流環境因子間量化性之關係作一探討。因MI 常用為河川生態狀況之重要指標，故此種量化性之關係，可用來做改善環境因子（如流量及水質參數）之根據。本研究所用之數據為維吉尼亞州環境品質局於1994 年至2001 年所收集之資料，MI 族群之分類指標為物種之數量及多樣性、數量最多之二個物種、最敏感物種之比例，以及最抗污染物種之比例。考慮之溪流環境因子共有20 個，其中8 個為物理及化學方面之因子，其他12 個則與棲息地有關。研究結果顯示在溪流中懸浮固體（TSS）濃度從9 mg/l 升高到17 mg/l 時，MI 物種之數量及多樣性有顯著的減少，流量到85 CFS 以上時亦有相同之情形。在溶氧量增加時，最敏感物種之比例亦隨之增加，而最抗污物種及數量最多之二個物種之比例則相對減少。另外，所用之數據之pH 值在6 至9 之間，對MI 似無任何影響。在棲地因子方面，MI 族群數量及多樣性，以及最敏感物種之比例，都與流量及河床介質有正面之相關關係，而最抗污物種比例則與河床介質呈負面之相關關係。
• 中文關鍵字： Stream Environmental; Benthos; macroinvertebrate
• 英文關鍵字： Stream Environmental; Benthos; macroinvertebrate