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S.L. King

Publications and source records attributed to S.L. King.

12 recordsLinked to original sources
USGS2010

Effectiveness of capture techniques for rails in emergent marsh and agricultural wetlands

A reliable and effective technique for capturing rails would improve researchers' ability to study these secretive marsh birds. The time effectiveness and capture success of four methods for capturing rails in emergent marsh and agricultural wetlands in southern Louisiana and Texas were evaluated during winter and breeding seasons. Methods were hand and net capture from an airboat at night, an all-terrain vehicle (ATV) at night, an ATV during daylight rice harvest and passive capture using drop-door traps with drift fencing. Five hundred and twenty rails were captured (and 21 recaptures): 192 King Rails (Rallus elegans), 74 Clapper Rails (R. longirostris), 110 Virginia Rails (R. limicola), 125 Sora (Porzana Carolina) and 40 Yellow Rails (Coturnicops noveboracensis). Methods used at night were effective at capturing rails: capture from airboats yielded 2.13 rails per hour each airboat was operated and capture from ATVs yielded 1.80 rails per hour each ATV was operated. During daylight, captures from ATVs during rice harvest (0.25 rails per hour each ATV was operated) and passive drop-door traps with drift fencing (0.0054 rails per trap hour) were both inefficient.

Waterbirds↗
USGS2009

Use of morphometric measurements to differentiate between species and sex of king and clapper rails

King Rails (Rallus elegans) and Clapper Rails (Rallus longirostris) are large, secretive waterbirds whose ranges overlap in brackish marshes along the Atlantic and Gulf Coasts. King and Clapper Rails are difficult to separate by physical appearance and there is currently no reliable method to distinguish between the two species. Here, the relative effectiveness of using discriminant analysis of morphometric measurements to identify and sex King and Clapper Rails was examined. Mean measurements of wing, tarsus, and weight were different between male King and Clapper Rails and between female King and Clapper Rails. However, for all measurements except culmen, male Clapper Rails and female King Rails were not different. Discriminate analysis of morphometric measurements revealed that wing, tarsus, and culmen measurements differentiated between King and Clapper Rails, but cross-validation results for male Clapper Rails were only 73%. Male King Rails were larger than female King Rails for all morphometric measurements and male Clapper Rails were larger than female Clapper Rails for all morphometric measurements except for the tail. Wing and tarsus measurements differentiated between male and female King Rails and wing, tarsus, and culmen measurements differentiated between male and female Clapper Rails.

Waterbirds↗
USGS2008

Spatial dynamics of overbank sedimentation in floodplain systems

Floodplains provide valuable social and ecological functions, and understanding the rates and patterns of overbank sedimentation is critical for river basin management and rehabilitation. Channelization of alluvial systems throughout the world has altered hydrological and sedimentation processes within floodplain ecosystems. In the loess belt region of the Lower Mississippi Alluvial Valley of the United States, channelization, the geology of the region, and past land-use practices have resulted in the formation of dozens of valley plugs in stream channels and the formation of shoals at the confluence of stream systems. Valley plugs completely block stream channels with sediment and debris and can result in greater deposition rates on floodplain surfaces. Presently, however, information is lacking on the rates and variability of overbank sedimentation associated with valley plugs and shoals. We quantified deposition rates and textures in floodplains along channelized streams that contained valley plugs and shoals, in addition to floodplains occurring along an unchannelized stream, to improve our understanding of overbank sedimentation associated with channelized streams. Feldspar clay marker horizons and marker poles were used to measure floodplain deposition from 2002 to 2005 and data were analyzed with geospatial statistics to determine the spatial dynamics of sedimentation within the floodplains. Mean sediment deposition rates ranged from 0.09 to 0.67??cm/y at unchannelized sites, 0.16 to 2.27??cm/y at shoal sites, and 3.44 to 6.20??cm/y at valley plug sites. Valley plug sites had greater rates of deposition, and the deposited sediments contained more coarse sand material than either shoal or unchannelized sites. A total of 59 of 183 valley plug study plots had mean deposition rates > 5??cm/y. The geospatial analyses showed that the spatial dynamics of sedimentation can be influenced by the formation of valley plugs and shoals on channelized streams; however, responses can vary. Restoration efforts in the region need to have basinwide collaboration with landowners and address catchment-scale processes, including the geomorphic instability of the region, to be successful. ?? 2008 Elsevier B.V. All rights reserved.

Geomorphology↗
USGS2006

Towards sustainable management of Louisiana's coastal wetland forests: Problems, constraints, and a new beginning

Over 345,000 ha of forested swamps occur throughout the Mississippi River Deltaic Plain. Natural and anthropogenic changes in hydrology and geomorphology at local and landscape levels have reduced the productivity in many of these coastal wetland forests areas and have caused the complete loss of forest cover in some places. A summary and interpretation of the available science, suggestions for policy change, and a multidisciplinary (multi-responsibility) approach were needed to address these issues [in the context of private land]. In response, the Louisiana Governor's office formed a Coastal Wetland Forest Conservation and Use Science Working Group (SWG) and an associated Advisory Panel to provide the Governor with information and suggestions of strategies for environmental and economic utilization, conservation, and protection of Louisiana's coastal wetland forest ecosystem in the long-term. The process of engaging scientists, resource managers, and other stakeholders in this effort is described, and the recommendations of the SWG are presented relative to forestry practices and the potential for sustainable management of coastal wetland forests.

Louisiana↗
USGS2003

Vegetation, soil, and flooding relationships in a blackwater floodplain forest

Hydroperiod is considered the primary determinant of plant species distribution in temperate floodplain forests, but most studies have focused on alluvial (sediment-laden) river systems. Few studies have evaluated plant community relationships in blackwater river systems of the South Atlantic Coastal Plain of North America. In this study, we characterized the soils, hydroperiod, and vegetation communities and evaluated relationships between the physical and chemical environment and plant community structure on the floodplain of the Coosawhatchie River, a blackwater river in South Carolina, USA. The soils were similar to previous descriptions of blackwater floodplain soils but had greater soil N and P availability, substantially greater clay content, and lower soil silt content than was previously reported for other blackwater river floodplains. Results of a cluster analysis showed there were five forest communities on the site, and both short-term (4 years) and long-term (50 years) flooding records documented a flooding gradient: water tupelo community > swamp tupelo > laurel oak = overcup oak > mixed oak. The long-term hydrologic record showed that the floodplain has flooded less frequently from 1994 to present than in previous decades. Detrended correspondence analysis of environmental and relative basal area values showed that 27% of the variation in overstory community structure could be explained by the first two axes; however, fitting the species distributions to the DCA axes using Gaussian regression explained 67% of the variation. Axes were correlated with elevation (flooding intensity) and soil characteristics related to rooting volume and cation nutrient availability. Our study suggests that flooding is the major factor affecting community structure, but soil characteristics also may be factors in community structure in blackwater systems. ?? 2003, The Society of Wetland Scientists.

Wetlands↗
USGS2002

Evaluation of reforestation in the Lower Mississippi River Alluvial Valley

Only about 2.8 million ha of an estimated original 10 million ha of bottomland hardwood forests still exist in the Lower Mississippi River Alluvial Valley (LMAV) of the United States. The U.S. Fish and Wildlife Service, the U.S. Forest Service, and state agencies initiated reforestation efforts in the late 1980s to improve wildlife habitat. We surveyed restorationists responsible for reforestation in the LMAV to determine the magnitude of past and future efforts and to identify major limiting factors. Over the past 10 years, 77,698 ha have been reforested by the agencies represented in our survey and an additional 89,009 ha are targeted in the next 5 years. Oaks are the most commonly planted species and bare-root seedlings are the most commonly used planting stock. Problems with seedling availability may increase the diversity of plantings in the future. Reforestation in the LMAV is based upon principles of landscape ecology; however, local problems such as herbivory, drought, and flooding often limit success. Broad-scale hydrologic restoration is needed to fully restore the structural and functional attributes of these systems, but because of drastic and widespread hydrologic alterations and socioeconomic constraints, this goal is generally not realistic. Local hydrologic restoration and creation of specific habitat features needed by some wildlife and fish species warrant attention. More extensive analyses of plantings are needed to evaluate functional success. The Wetland Reserve Program is a positive development, but policies that provide additional financial incentives to landowners for reforestation efforts should be seriously considered.

Restoration Ecology↗
USGS2002

Effects of canopy gaps and flooding on homopterans in a bottomland hardwood forest

Canopy disturbance is a major factor affecting forest structure and composition and, as a result of habitat alterations, can influence insect communities. We initiated a field study to quantify the effects of canopy disturbance on aerial insect abundance and distribution within a bottomland hardwood forest along the Cache River, Arkansas, USA. We used passive flight-intercept traps to sample insects in canopy gap and forest interior habitats from May to July in 1996, 1997, and 1998. The hydrologic conditions of our study site varied among years: 1996 was relatively dry, 1997 incurred a long-duration flood, and 1998 was moderately wet. Of the 34,000+ Homopterans collected, many groups were distributed in a non-uniform manner among years and between habitats. Total Homopterans, two families of Homopterans, and six morphospecies were more abundant in canopy gaps than interior forest. Many Homopteran taxa were least abundant in 1997 following almost six months of flooding. Alternatively, relatively large Homopteran abundances were associated with the dry conditions of 1996 and the moderately wet conditions of 1998. Differences in Homopteran abundance among years and habitats may be related to differences in vegetation density. Canopy gaps supported more vegetation cover than the interior forest in all but the first sampling interval. In addition, similar to Homopteran abundance, vegetation density was lower in 1997 than in 1998. These results demonstrate that natural disturbance and flooding contribute to Homopteran abundance and distribution patterns in bottomland hardwood forests of the south central United States.

Arkansas↗
USGS2000

Vegetation and soils

haracterization of bottomland hardwood vegetation in relatively undisturbed forests can provide critical information for developing effective wetland creation and restoration techniques and for assessing the impacts of management and development. Classification is a useful technique in characterizing vegetation because it summarizes complex data sets, assists in hypothesis generation about factors influencing community variation, and helps refine models of community structure. Hierarchical classification of communities is particularly useful for showing relationships among samples (Gauche 1982).

Book chapter↗
USGS2000

Vegetation dynamics

A disturbance can be defined as 'any relatively discrete event in time that disrupts ecosystem, community, or population structure and changes resources, substrate availability, or the physical environment' (Pickett and White 1985). Vegetation dynamics are a function of the temporal and spatial patterns of the disturbance regime. Natural disturbance regimes support the highest biological diversity; therefore, forest management practices that most closely mimic natural disturbances are expected to sustain the highest biological diversity within a given area (Denslow 1980). In southern forested wetlands, flooding is the dominant disturbance factor, thus plant species are usually distributed along a gowing-season flood gradient (Franz and Bassas 1977).

Book chapter↗
USGS1998

Long-term effects of a lock and dam and greentree reservoir management on a bottomland hardwood forest

We investigated the long-term effects of a lock and dam and greentree reservoir management on a riparian bottomland hardwood forest in southern Arkansas, USA, by monitoring stress, mortality, and regeneration of bottomland hardwood trees in 53 permanent sampling plots from 1987-1995. The lock and dam and greentree reservoir management have altered the timing, depth, and duration of flooding within the wetland forest. Evaluation of daily river stage data indicates that November overbank flooding (i.e. 0.3 m above normal pool) of 1 week duration occurred only 10 times from 1950 to 1995 and four of these occurrences were the result of artificial flooding of the greentree reservoir. Results of the vegetation study indicate that the five most common dominant and co-dominant species were overcup oak, water hickory, Nuttall oak, willow oak, and sweetgum. Mortality of willow oak exceeded that of all other species except Nuttall oak. Nuttall oak, willow oak, and water hickory had much higher percentages of dead trees concentrated within the dominant and co-dominant crown classes. Probit analysis indicated that differences in stress and mortality were due to a combination of flooding and stand competition. Overcup oak appears to exhibit very little stress regardless of crown class and elevation and, with few exceptions, had a significantly greater probability of occurring within lower stress classes than any other species. Only 22 new stems were recruited into the 5 cm diameter-at-breast height size class between 1990-1995 and of these, three were Nuttall oak, three were water hickory, and one was sweetgum. No recruitment into the 5 cm diameter-at-breast height size class occurred for overcup oak or willow oak. The results of the study suggest that the forest is progressing to a more water-tolerant community dominated by overcup oak. A conservative flooding strategy would minimize tree stress and maintain quality wildlife habitat within the forested wetland.The long-term effects of a lock and dam and greentree reservoir management on a riparian bottomland hardwood forest in southern Arkansas, USA, were investigated by monitoring stress, mortality, and regeneration of bottomland hardwood trees in 53 permanent sampling plots from 1987-1995. Results of the study suggest that the forest is progressing to a more water-tolerant community dominated by overcup oak.

Forest Ecology and Management↗