A process-based classification system for headwater streams
The AA. develop a classification system for small headwater streams predicated upon an understanding of the dominant pysical processes acting in the channel and its basin, and the conditions under which these processes operate. The variables used
to build the classification are hillslope gradient, valley width as compared to channel width, channel gradient, channel depth and sediment size. This classification system provides the foundation for building an approach for identifying basins and sreams
an interdisciplinary approach based on a large variety of analytical methods, including from geomorphology, sedimentology, hydrology, hydrochemistry, dendrochronology, geodesy, statistics and geographic information systems. The role played by headwater areas in relief
The purpose of this paper is to describe the complexity of headwater areas in terms of relief and rates of morphological change, as well as the role headwater areas play in the development of mountain areas. The complexity of headwater areas demands
development is relevant from the perspective of mountain-range morphometry, as well as in terms of the frequency and intensity of morphological processes. The relief of headwater areas affects natural processes further downstream, this being the direct result
of conditions for the transport of mineral matter in the headwater area. - (BJ)
Differing responses to extreme rainfall events in headwater areas recorded by wood anatomy in roots (Gorce Mountains, Poland)
Années 1944-2001 ; Bassin-versant ; Carpates ; Dendrogéomorphologie ; Dendrologie ; Mouvement de masse ; Phénomène extrême ; Pologne ; Précipitation ; Système racinaire
Carpathian Mountains ; Dendrogeomorphology ; Dendrology ; Extreme event ; Mass movement ; Poland ; Precipitation ; Root system ; Watershed
roots. The results showed that the headwater areas experienced a variety of geomorphic processes. The timing of processes was assessed for the years 1944 to 2001. The main difference between the roots can be observed between the upper and lower parts
of the headwater area. In the upper part of the headwater area, anatomical changes within the roots were observed when heavy rainfall events occurred, i.e. in 1958, 1970, 1971, 1972, and 1985. Roots in the lower part of the headwater area had become exposed during
continuous rainfalls in 1997 and 2001. This research provides a fundamental review of dendrogeomorphological methodology applied to the identification of extreme geomorphic events acting within headwater areas.
Fluvial carbon flux from headwater peatland streams : significance of particulate carbon flux
(DOC) and particulate form (POC) are decreasing from the headwaters to the main catchment outlet. In contrast to less eroded systems fluvial organic carbon flux is dominated by POC. POC:DOC ratios decrease from values of 4 in the headwaters to close
to unity at the catchment outlet. These results demonstrate the importance of eroding headwater sites as sources of POC to the fluvial system. Comparison with a range of catchment characteristics reveals that drainage density is the best predictor
This paper presents the first detailed assessment of dissolved and organic carbon losses from a severely eroded headwater peatland (River Ashop in the English Peak District, South Pennines, UK). Total annual fluvial organic carbon losses in dissoved
of POC:DOC but there is scatter in the relation in the headwaters.
Character of headwaters adjustment to base level drop, investigated by digital modeling
Special issue : Geomorphic systems
The AA. investigate river profile response to continuous base level drops using a computer model. In the analysis of results, they pay particular attention to indicators of headwaters erosional response to this type of base level change.
The complex nonlinear systems with fractal as well as chaotic dynamics of annual runoff processes in the three headwaters of the Tarim River
. The main findings are : 1) the annual runoff processes of the 3 headwaters of the Tarim River are complex nonlinear systems with fractal as well as chaotic dynamics; 2) the correlation dimensions of attractor derived from the time series of the annual
This paper attempted to identify fractal and chaotic characteristics of the annual runoff processes in headwaters of the Tarim River. Methods of fractal analyses were used to explore several aspects of the temporal changes from 1957 to 2002
runoff for the Hotan, Yarkand and Aksu rivers imply that all 3 rivers are chaotic dynamical systems that are sensitive to initial conditions, and the dynamic modeling of their annual runoff processes requires at least 4 independent variables; 3) the time
Integrated toposequence analysis at the confluence zone of the River Ebonyi headwater catchment (south eastern Nigeria)
Integrated Toposequence Analysis (ITA) as presented in this paper provides a methodology that combines conventional bio-physical and participatory research techniques in the study of land use systems and land resource evaluation along toposequences
Using LIDAR data to map gullies and headwater streams under forest canopy : South Carolina, USA
Capacité des données topographiques ALS pour identifier, cartographier et mesurer la morphologie de deux systèmes de ravins sous une canopée forestière épaisse dans la région du Piedmont de Caroline du sud, E.U.
. Tills in the headwaters region of the ancient Mississippi drainage system in Minnesota and Wisconsin occur in the appropriate stratigraphic position and have colors and mineralogic compositions that suggest they could be the parent till of the Roxana.
Agriculture ; Aptitude culturale ; Conservation des sols ; Erosion des sols ; Exploitation agricole ; Géographie de l'Afrique ; Législation ; Milieu humide ; Système de culture ; Utilisation du sol ; Zimbabwe
The conservation status of dambos, a particular type of wetland associated with the headwaters of rivers draining the central plateau area, is examined in terms of past and present utilisation and erosion problems. The past-1950 phase was one
Impact of polder system on flooding in the Rolava River basin
This paper deals with evaluating the impact of dry reservoirs on flood events. The system of dry reservoirs could create an effective part of integrated flood protection. The system of four uncontrolled dry reservoirs was theoretically implemented
to the headwater part of the Rolava River basin in the Ore Mountains. The main aim was to evaluate the potential impact of the dry reservoirs on peak discharge decrease during two known rainfall events in September 2007 and in August 2006. - (EN)
Recent trends in rivers with near-natural flow regime : The case of the river headwaters in Spain
The aim of this research was to study the streamflow evolution of a representative sample of the Spanish near-natural-regime fluvial system over the last 4 decades of the 20th century. A representative sample of 74 rivers was selected
of source samples to test the method, then applied the technique to a field sample from a depositional basin. The site selected for sampling encompassed 3 large, contiguous catchments in the USA (headwater-Mississippi, Minnesota, and St. Croix), that deliver
sediment to an isolated depositional basin, Lake Pepin. The beds of each river system are composed of sediments derived from glacial deposits of different ages and geographic origins, so the method should effectively distinguish the different sources.
(a dissected volcano), the reforestation of headwater reaches within a short interval of initial clearance, and the location of urban impacts that are concentrated in the lower part of the river system.
Comparison of two stream gauging systems for measuring runoff and sediment yield for a semi-arid watershed
) sediment fractions exported, but consistently underestimated the coarse (> 0.5 mm) sediment fractions. This study outlines the benefits and limitations of the pump sampler based system for monitoring sediment concentration and yield in high-energy headwater
An arid watershed at the Walnut Gulch Experimental Watershed (WGEW) near Tombstone, AZ, was instrumented with both systems and hydrologic and sediment data were collected and compared during a 2 year period. Total sediment yield for the entire
Interaction between the controls on fluvial system development: tectonics, climate, base level and river capture – Rio Alias, Southeast Spain
-level change or river capture to varying degrees. The connectivity of the system from the headwaters to the coast decreased through time as incision progressed, resulting in changes in local coupling characteristics.
This paper examined the impact of a hillslope failure on a headwater channel system in the UK uplands, Wet Swine Gill in the northern Lake District. The primary aim was to account for sediment transfer in the failure event and post-event sediment
the limits of this approach and the accuracy of the sediment budget models that are developed. The AA. aim also to assess the relationship between contemporary meteorological (climate) conditions and sediment system response.
In the Kotaki River Valley, Japan, sediment-related disasters occur over extensive areas from headwater to downstream cities and in a variety of forms. On the Kotaki River, the potentially large quantity of sediment discharge during floods
was reduced by installing 3 sets of slit barriers to prevent landslides while allowing the passage of fish. This dam system was modelled after extant slit barriers of this nature. Previous investigations of temporal changes in sediment-regulating function
from headwaters, hillslopes and tributary streams. Additionally, soil development and radiocarbon ages, together with local and regional paleoclimate reconstructions, were used to infer the range of processes acting in this system. The AA. discuss
sediment production and sediment delivery processes within alpine geomorphic systems. Moose Lake contains a partially varved record indicating variable rates of accumulation during the last millennium that, in general, coincide with previously documented
LIA glacial advances in the region and locally. Dendrochronological assessment of forefield surfaces in the headwaters of the catchment (Reef Icefield), increases in varve thickness within 8 Moose Lake sediment cores and elevated carbonate