Mapping first‐order controls on streamflow from drainage basins: the T³ template

Abstract

Recent calls for drainage basin classification have highlighted the advantages of such efforts, including: identification of important controls on water fluxes and pathways; guidance on basin similarities and differences that could facilitate modelling and experimental approaches; and provision of a common language to assist in the discussions of inter-basin similarities and differences at regional, national, and global scales (McDonnell and Woods, 2004). There are several examples of basin classification in terms of hydrograph characteristics, such as the work of Richards (1990) and Poff et al. (1997) in North America and Harris et al. (2000) in the United Kingdom.These classification schemes have often been based on streamflow response, which integrates spatial patterns in hydrological processes that control streamflow measured at the gauging station (Beven, 2000), with the goal of identifying the linkages between streamflow properties and aquatic ecology. These classification efforts may be of considerable assistance in understanding the ecological significance of flow regimes and their management in order to protect or restore fluvial systems (Harris et al., 2000). However, their ability to infer the nature, magnitude, and spatial and temporal distribution of intra-basin hydrologic processes based on streamflow behaviour is limited. Information on the internal hydrologic behaviour of drainage basins is particularly needed to identify inter-basin similarities and differences in terms of their response to natural and anthropogenic disturbance (e.g. climatic change, fire, insect infestation, forest management, urban development).Alternative basin classification systems provide greater insight into the hydrologic controls on streamflow produced from drainage basins. One example is the 'hydrologic landscapes' concept proposed by Winter (2001) and colleagues (Wolock et al., 2004) for the United States. A statistical approach was used to subdivide the country into hydrologic landscape regions (HLRs) based on the combination of natural factors (climate, geology, topography) that are assumed to control the delivery of water to stream channels. Landscapes were delimited according to the balance between annual precipitation and potential evapotranspiration (P-PET), bedrock permeability, percent of sand content in soil cover, and topography. Cluster analysis was used to group over 40 000 basins (each ∼200 km 2 in size) into 20 non-contiguous regions. Wolock et al. (2004) suggest that these HLRs can assist in a variety of environmental management efforts, such as water-quality sampling network design, synthesis of results

Macroinvertebrate community response to inter‐annual and regional river flow regime dynamics

“…The methodological approach employed demonstrates the value of identifying distinct river regime types, which may be grouped into physically-interpretable hydrological regions (e.g. Buttle, 2006;Kingston et al, 2006;Wagener et al, 2007). The results also clearly indicate that significant inter-annual regime variability occurs and that this can be clearly detected at a national and regional scale ( Figure 3 and Table 2).…”

Controls on snowmelt water mean transit times in northern boreal catchments

“…As such, these northern Swedish catchments appear to behave similar (with respect to topographic controls on transit times) to the Scottish Highland catchments . Taken together, it can be seen that these landscape and topographic factors are related (Buttle, 2006;Tetzlaff et al, 2009b). That is, wetlands with responsive soils Soulsby et al, 2006b) and/or near-surface impervious ice layers during snowmelt co-evolve with landscape positions with lower gradients.…”

“…These are the first two Ts of the Buttle's (2006) T 3 template. The third T, topology, deals primarily with stream or channel network configurations that are often assumed negligible (for simplicity) in small-catchment systems or with the connectivity across landscape units.…”

“…topography leads to soil formation which, in turn, influences topography) at long time scales. This has led recently to more holistic approaches to catchment hydrology such as Buttle's T 3 template (Buttle, 2006), which recognizes that all components of a natural system (hydrology, ecology, topography, etc.) develop in concert .…”

Advances in Canadian Forest Hydrology, 2003-2007

“…Thus, on the western Boreal Plain of Alberta (where PPT<PET and there is often little or no annual runoff ), critical hydrologic indicators might be soil water storage and the direction of groundwater flux between hillslopes and wetlands (Devito et al, 2005a), whereas on the eastern Boreal Shield of Quebec (where PPT>PET and there is always annual runoff ) critical indicators might include peak and low streamflows (Guillemette et al, 2005;Sanford et al, 2007). Buttle (2006) presented a template for assessing the interactive effects of the dominant controls on basin streamflow in a given HRU. Three first-order controls on streamflow characteristics were proposed under a specific hydroclimatic condition: typology (ability of different landscape elements to generate runoff ), topography (via hydrologic connectivity between different landscape elements and the ability of runoff to reach the drainage network), and topology (influence of a drainage network on routing runoff contributions to the basin outlet).…”