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Mary Ann Madej

Publications and source records attributed to Mary Ann Madej.

At least 37 records · Page 2Linked to original sources
USGS2006

Optimization strategies for sediment reduction practices on roads in steep, forested terrain

Many forested steeplands in the western United States display a legacy of disturbances due to timber harvest, mining or wildfires, for example. Such disturbances have caused accelerated hillslope erosion, leading to increased sedimentation in fish-bearing streams. Several restoration techniques have been implemented to address these problems in mountain catchments, many of which involve the removal of abandoned roads and re-establishing drainage networks across road prisms. With limited restoration funds to be applied across large catchments, land managers are faced with deciding which areas and problems should be treated first, and by which technique, in order to design the most effective and cost-effective sediment reduction strategy. Currently most restoration is conducted on a site-specific scale according to uniform treatment policies. To create catchment-scale policies for restoration, we developed two optimization models - dynamic programming and genetic algorithms - to determine the most cost-effective treatment level for roads and stream crossings in a pilot study basin with approximately 700 road segments and crossings. These models considered the trade-offs between the cost and effectiveness of different restoration strategies to minimize the predicted erosion from all forest roads within a catchment, while meeting a specified budget constraint. The optimal sediment reduction strategies developed by these models performed much better than two strategies of uniform erosion control which are commonly applied to road erosion problems by land managers, with sediment savings increased by an additional 48 to 80 per cent. These optimization models can be used to formulate the most cost-effective restoration policy for sediment reduction on a catchment scale. Thus, cost savings can be applied to further restoration work within the catchment. Nevertheless, the models are based on erosion rates measured on past restoration sites, and need to be up-dated as additional monitoring studies evaluate long-term basin response to erosion control treatments. Copyright ?? 2006 John Wiley & Sons, Ltd.

Earth Surface Processes and Landforms↗
USGS2006

Assessing possible thermal rearing restrictions for juvenile coho salmon (Oncorhynchus kisutch) through thermal infrared imaging and in-stream monitoring, Redwood Creek, California

We quantified patterns in stream temperature in a northern coastal California river using thermal infrared (TIR) imaging and in-stream monitoring and related temperature patterns to the historical and present distributions of juvenile coho salmon (Oncorhynchus kisutch). In Redwood Creek, California, water temperature increased from the headwaters to about 60 km downstream, then gradually decreased over the next 40 km as the river approaches the Pacific Ocean. Despite the lack of fish migration barriers, juvenile coho are currently only observed in the downstream-most 20 km, whereas historically they were found in 90 km of river channel. Maximum daily temperatures and duration of elevated stream temperatures were not significantly different in the headwater and downstream reaches but were significantly higher in the 50 km long intervening reach, where maximum weekly maximum temperatures ranged from 23 to 27??C. An increase in stream temperatures in the middle basin during the last three decades as a result of channel aggradation, widening, and the removal of large riparian conifers may play an important role in restricting juvenile coho to one-fifth of their historical range. ?? 2006 NRC.

Canadian Journal of Fisheries and Aquatic Sciences↗
USGS2005

The role of organic matter in sediment budgets in forested terrain

The production and transport of suspended particulate matter usually are major components of a sediment budget, but the organic and inorganic fractions of this material are not commonly differentiated. In four forested streams in the northwestern United States, the organic content of suspended sediment samples ranged from 10 to 80 weight percent for individual flood events. For a given stream, as a percentage of suspended sediment, organic content was highest during base flows and the early rising and late falling limbs of hydrographs, but on an annual cumulative basis, most organic flux occurred during a few days of high flow. By weight, the inorganic component of suspended sediment dominated the annual sediment flux in three of the catchments, but organics represented more than half the suspended sediment load in an old growth redwood stream. Although commonly minor by weight, organic suspended sediment can have important effects on aquatic biological communities, turbidity measurements, and eutrophication in estuaries.

Conference Paper↗
USGS2004

Benefits and impacts of road removal

Road removal is being used to mitigate the physical and ecological impacts of roads and to restore both public and private lands. Although many federal and state agencies and private landowners have created protocols for road removal and priorities for restoration, research has not kept pace with the rate of removal. Some research has been conducted on hydrologic and geomorphic restoration following road removal, but no studies have directly addressed restoring wildlife habitat. Road removal creates a short-term disturbance which may temporarily increase sediment loss. However, long-term monitoring and initial research have shown that road removal reduces chronic erosion and the risk of landslides. We review the hydrologic, geomorphic, and ecological benefits and impacts of three methods of road removal, identify knowledge gaps, and propose questions for future research, which is urgently needed to quantify how effectively road removal restores terrestrial, riparian, and aquatic habitat and other ecosystem processes.

Frontiers in Ecology and the Environment↗
USGS2001

Erosion and sediment delivery following removal of forest roads

Erosion control treatments were applied to abandoned logging roads in California, with the goal of reducing road-related sediment input to streams and restoring natural hydrologic patterns on the landscape. Treatment of stream crossings involved excavating culverts and associated road fill and reshaping streambanks. A variety of techniques were applied to road benches, which included decompacting the road surface, placing unstable road fill in more stable locations, and re-establishing natural surface drainage patterns. Following treatment and a 12-year recurrence-interval storm, some road reaches and excavated stream crossings showed evidence of mass movement failures, gullying, bank erosion and channel incision. Post-treatment erosion from excavated stream crossings was related to two variables: a surrogate for stream power (drainage area × channel gradient) and the volume of fill excavated from the channel. Post-treatment erosion on road reaches was related to four explanatory variables: method of treatment, hillslope position (upper, mid-slope or lower), date of treatment, and an interaction term (hillslope position × method of treatment). Sediment delivery from treated roads in upper, middle and lower hillslope positions was 10, 135 and 550 m 3 of sediment per kilometre of treated roads, respectively. In contrast, inventories of almost 500 km of forest roads in adjacent catchments indicate that untreated roads produced 1500 to 4700 m 3 of sediment per kilometre of road length. Erosion from 300 km of treated roads contributed less than 2 per cent of the total sediment load of Redwood Creek during the period 1978 to 1998. Although road removal treatments do not completely eliminate erosion associated with forest roads, they do substantially reduce sediment yields from abandoned logging roads.

Earth Surface Processes and Landforms↗
USGS2001

Development of channel organization and roughness following sediment pulses in single‐thread, gravel bed rivers

Large, episodic inputs of coarse sediment (sediment pulses) in forested, mountain streams may result in changes in the size and arrangement of bed forms and in channel roughness. A conceptual model of channel organization delineates trajectories of response to sediment pulses for many types of gravel bed channels. Channels exhibited self‐organizing behavior to various degrees based on channel gradient, presence of large in‐channel wood or other forcing elements, the size of the sediment pulse, and the number of bed‐mobilizing flows since disturbance. Typical channel changes following a sediment pulse were initial decreases in water depth, in variability of bed elevations, and in the regularity of bed form spacing. Trajectories of change subsequently showed increased average water depth, more variable and complex bed topography, and increased uniformity of bed form spacing. Bed form spacing in streams with abundant forcing elements developed at a shorter spatial scale (two to five channel widths) than in streams without such forcing mechanisms (five to 10 channel widths). Channel roughness increased as bed forms developed.

Water Resources Research↗
USGS2000

Variability of bed mobility in natural, gravel‐bed channels and adjustments to sediment load at local and reach scales

Local variations in boundary shear stress acting on bed‐surface particles control patterns of bed load transport and channel evolution during varying stream discharges. At the reach scale a channel adjusts to imposed water and sediment supply through mutual interactions among channel form, local grain size, and local flow dynamics that govern bed mobility. In order to explore these adjustments, we used a numerical flow model to examine relations between model‐predicted local boundary shear stress (т j ( and measured surface particle size ( D 50 ) at bank‐full discharge in six gravel‐bed, alternate‐bar channels with widely differing annual sediment yields. Values of т j and D 50 were poorly correlated such that small areas conveyed large proportions of the total bed load, especially in sediment‐poor channels with low mobility. Sediment‐rich channels had greater areas of full mobility; sediment‐poor channels had greater areas of partial mobility; and both types had significant areas that were essentially immobile. Two reach‐mean mobility parameters (Shields stress and Q *) correlated reasonably well with sediment supply. Values which can be practicably obtained from carefully measured mean hydraulic variables and particle size would provide first‐order assessments of bed mobility that would broadly distinguish the channels in this study according to their sediment yield and bed mobility.

Water Resources Research↗
USGS1999

Temporal and spatial variability in thalweg profiles of a gravel-bed river

This study used successive longitudinal thalweg profiles in gravel-bed rivers to monitor changes in bed topography following floods and associated large sediment inputs. Variations in channel bed elevations, distributions of residual water depths, percentage of channel length occupied by riffles, and a spatial autocorrelation coefficient (Moran's I ) were used to quantify changes in morphological diversity and spatial structure in Redwood Creek basin, northwestern California. Bed topography in Redwood Creek and its major tributaries consists primarily of a series of pools and riffles. The size, frequency and spatial distribution of the pools and riffles have changed significantly during the past 20 years. Following large floods and high sediment input in Redwood Creek and its tributaries in 1975, variation in channel bed elevations was low and the percentage of the channel length occupied by riffles was high. Over the next 20 years, variation in bed elevations increased while the length of channel occupied by riffles decreased. An index [(standard deviation of residual water depth/bankfull depth) × 100] was developed to compare variations in bed elevation over a range of stream sizes, with a higher index being indicative of greater morphological diversity. Spatial autocorrelation in the bed elevation data was apparent at both fine and coarse scales in many of the thalweg profiles and the observed spatial pattern of bed elevations was found to be related to the dominant channel material and the time since disturbance. River reaches in which forced pools dominated, and in which large woody debris and bed particles could not be easily mobilized, exhibited a random distribution of bed elevations. In contrast, in reaches where alternate bars dominated, and both wood and gravel were readily transported, regularly spaced bed topography developed at a spacing that increased with time since disturbance. This pattern of regularly spaced bed features was reversed following a 12-year flood when bed elevations became more randomly arranged.

Earth Surface Processes and Landforms↗
USGS1996

Channel response to sediment wave propagation and movement, Redwood Creek, California, USA

Redwood Creek, north coastal California, USA, has experienced dramatic changes in channel configuration since the 1950s. A series of large floods (in 1955, 1964, 1972 and 1975) combined with the advent of widespread commercial timber harvest and road building resulted in extensive erosion in the basin and contributed high sediment loads to Redwood Creek. Since 1975, no peak flows have exceeded a 5 year recurrence interval. Twenty years of cross-sectional survey data document the downstream movement of a ‘sediment wave’ in the lower 26 km of this gravel-bedded river at a rate of 800 to 1600 m a −1 during this period of moderately low flows. Higher transit rates are associated with reaches of higher unit stream power. The wave was initially deposited at a site with an abrupt decrease in channel gradient and increase in channel width. The amplitude of the wave has attenuated more than 1 m as it moved downstream, and the duration of the wave increased from eight years upstream to more than 20 years downstream. Channel aggradation and subsequent degradation have been accommodated across the entire channel bed. Channel width has not decreased significantly after initial channel widening from large (>25 year recurrence interval) floods. Three sets of longitudinal surveys of the streambed showed the highest increase in pool depths and frequency in a degrading reach, but even the aggrading reach exhibited some pool development through time. The aggraded channel bed switched from functioning as a sediment sink to a significant sediment source as the channel adjusted to high sediment loads. From 1980 to 1990, sediment eroded from temporary channel storage represented about 25 per cent of the total sediment load and 95 per cent of the bedload exported from the basin.

California↗
USGS1994

Analysis of bank erosion on the Merced River, Yosemite Valley, Yosemite National Park, California, USA

Channel changes from 1919 to 1989 were documented in two study reaches of the Merced River in Yosemite National Park through a review of historical photographs and documents and a comparison of survey data. Bank erosion was prevalent and channel width increased an average of 27% in the upstream reach, where human use was concentrated. Here, trampling of the banks and riparian vegetation was common, and banks eroded on straight stretches as frequently as on meander bends. Six bridges in the upper reach constrict the channel by an average of 38% of the original width, causing severe erosion. In the downstream control reach, where human use was minimal, channel widths both decreased and increased, with a mean increase of only 4% since 1919. Bank erosion in the control reach occurred primarily on meander bends. The control reach also had denser stands of riparian vegetation and a higher frequency of large woody debris in channels. There is only one bridge in the lower reach, located at the downstream end. Since 1919, bank erosion in the impacted upstream reach contributed a significant amount of sediment (74,800 tonnes, equivalent to 2.0 t/km 2 /yr) to the river. An analysis of 75 years of precipitation and hydrologic records showed no trends responsible for bank erosion in the upper reach. Sediment input to the upper reach has not changed significantly during the study period. Floodplain soils are sandy, with low cohesion and are easily detached by lateral erosion. The degree of channel widening was positively correlated with the percentage of bare ground on the streambanks and low bank stability ratings. Low bank stability ratings were, in turn, strongly associated with high human use areas. Channel widening and bank erosion in the upper reach were due primarily to destruction of riparian vegetation by human trampling and the effect of bridge constrictions on high flow, and secondarily to poorly installed channel revetments. Several specific recommendations for river restoration were provided to park management.

California↗