William H. Conner

William H. Conner
Clemson University | CU · Baruch Institute of Coastal Ecology and Forest Science

PhD, LSU 1988

About

182
Publications
28,846
Reads
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5,663
Citations
Citations since 2017
24 Research Items
1910 Citations
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20172018201920202021202220230100200300
20172018201920202021202220230100200300
Additional affiliations
February 1990 - present
Clemson University
Position
  • Professor
Description
  • Professor and Assistant Drector
August 1975 - February 1990
Louisiana State University
Position
  • Research Associate
Education
January 1982 - May 1988
Louisiana State University
Field of study
  • Forestry
August 1973 - June 1975
Louisiana State University
Field of study
  • Marine Science
September 1969 - June 1973

Publications

Publications (182)
Article
Full-text available
Rising sea levels and increasing salinity are impacting coastal forests of the Southern U.S. Forest productivity and composition was studied from 2014 to 2020 in paired plots (20 × 25-m) along a porewater salinity gradient (0, 0.8, 2.6, 4.6 PSU). Aboveground net primary productivity was estimated by summing annual litterfall and woody growth. In ad...
Chapter
Full-text available
Nowadays forest fires are so rare in the Mississippi Alluvial Valley and other floodplains of the southeastern USA that these floodplains appear fireproof. Fire was once much more common across the Southeastern Coastal Plain, including in these forested floodplains. Even so, fire was not the fundamental ecological disturbance in floodplain forests...
Article
Full-text available
The interception of precipitation by plant canopies can alter the amount and spatial distribution of water inputs to ecosystems. We asked whether canopy interception could locally augment water inputs to shrubs by their crowns funneling (freshwater) precipitation as stemflow to their bases, in a wetland where relict overstory trees are dying and pe...
Article
Full-text available
Here we review an extensive series of studies of Barataria Basin, an economically and ecologically important coastal basin of the Mississippi Delta. Human activity has greatly altered the hydrology of the basin by decreasing riverine inflows from leveeing of the river and its distributaries, increasing runoff with high nutrient concentrations from...
Article
Salinity intrusion is responsible for changes to freshwater wetland watersheds globally, but little is known about how wetland water budgets might be influenced by small increments in salinity. We studied a forested wetland in South Carolina, USA, and installed sap flow probes on 72 trees/shrubs along a salinity gradient. Species investigated inclu...
Article
Full-text available
Decomposing foliar litter organic matter (LOM) in forested watersheds is an essential terrestrial source of dissolved organic matter (DOM) to aquatic ecosystems. To evaluate the relationship of chemical composition between LOM and DOM, we collected freshly fallen leaves of white oak (Quercus alba) and conducted an 80-week field decomposition experi...
Article
As rising sea levels alter coastal ecosystems, there is a pressing need to examine the effects of saltwater intrusion on coastal communities. Using 16S Illumina profiling, we characterized the communities of baldcypress tree (Taxodium distichum) root endosphere and rhizosphere soil bacteria. Our study utilized established sites along salinity and f...
Article
Plant roots assemble two distinct microbial compartments: the rhizosphere (microbes in soil surrounding roots) and the endosphere (microbes within roots). Our knowledge of fungal community assembly in these compartments is limited, especially in wetlands. We tested the hypothesis that biotic factors would have direct effects on rhizosphere and endo...
Article
Foliar litter is an important terrestrial source of dissolved organic matter (DOM) and disinfection byproducts (DBPs) in the source water supply. Climate changes could alter precipitation patterns and hydroperiods in woody wetlands, resulting in a hydrologic shift along the low elevation gradient and change the productions of DOC and DBP precursors...
Article
Full-text available
There is a growing concern about the adverse effects of saltwater intrusion via tidal rivers, streams, and creeks into tidal freshwater forested wetlands (TFFW) due to sea level rise (SLR) and intense and extended drought events. However, the magnitude and duration of porewater salinity in exceedance of plant salinity stress threshold (2 practical...
Article
Full-text available
Occupancy patterns of herpetofauna in most tidal freshwater swamps are unknown. Tidal freshwater swamps currently face multiple threats, including salinization, which can influence their associated plant and animal communities. The impacts of salinization to herpetofauna communities in tidal freshwater swamps have not been assessed. To improve pred...
Presentation
Because of their ability to sequester carbon, tidal wetlands can serve as greenhouse gas (GHG) sinks. If managed properly, wetlands are a critical resource for climate adaptation and mitigation. The overall goal of this wetland assessment is to improve national capabilities to monitor and report on wetland change and effects on carbon sequestration...
Chapter
Full-text available
Tidally influenced coastal forested wetlands can be divided into two broad categories, mangroves and freshwater forested wetlands. These forested wetlands perform valuable ecosystem services, and both are endangered by threats of sea level rise and land use. Understanding the mechanisms that control the distribution of tidal forests has been greatl...
Article
Riverine forests support high rates of plant productivity, yet total wood carbon (C) stocks in these systems remain understudied. We measured C concentrations and dry mass of live and dead detrital wood to understand their importance relative to total ecosystem C storage across an elevation gradient on the floodplain of the Congaree River. Our stud...
Chapter
Bottomland hardwood ecosystems (BLH) occupy the floodplains of low-gradient streams and rivers in the Atlantic and Gulf Coastal Plain Provinces of the southeastern United States (figure 2-1; King et al. 2012). Although they make up a relatively small portion of the landscape compared to their upland counterparts, healthy BLH forests, particularly o...
Article
Carbon (C) standing stocks, C mass balance, and soil C burial in tidal freshwater forested wetlands (TFFW) and TFFW transitioning to low-salinity marshes along the upper estuary are not typically included in "blue carbon" accounting, but may represent a significant C sink. Results from two salinity transects along the tidal Waccamaw and Savannah ri...
Chapter
An assimilation wetland is a natural (non-constructed) wetland into which secondarily-treated, disinfected, non-toxic municipal effluent is discharged. In the Mississippi River Delta, the wetland is typically either a freshwater forested wetland (e.g., baldcypress-water tupelo) or a freshwater emergent wetland. These wetlands have been hydrology al...
Article
Forested wetlands dominated by baldcypress (Taxodium distichum) and water tupelo (Nyssa aquatica) are commonly found in coastal regions of the southeastern United States. Global climate change and in particular sea level rise will alter the frequency and magnitude of wet/dry periods and salinity levels in these ecosystems. Soil microcosm experiment...
Article
Full-text available
Coastal wetlands significantly contribute to global carbon storage potential. Sea-level rise and other climate change-induced disturbances threaten coastal wetland sustainability and carbon storage capacity. It is critical that we understand the mechanisms controlling wetland carbon loss so that we can predict and manage these resources in anticipa...
Raw Data
Coastal wetlands significantly contribute to global carbon storage potential. Sea-level rise and other climate change-induced disturbances threaten coastal wetland sustainability and carbon storage capacity. It is critical that we understand the mechanisms controlling wetland carbon loss so that we can predict and manage these resources in anticipa...
Article
Tidal freshwater forested wetlands (TFFW) of the southeastern United States are experiencing increased saltwater intrusion mainly due to sea-level rise. Inter-annual and intra-annual variability in forest productivity along a salinity gradient was studied on established sites. Aboveground net primary productivity (ANPP) of trees was monitored from...
Article
Full-text available
The objectives of this study were to identify processes that contribute to resilience of coastal wetlands subject to rising sea levels and to determine whether the relative contribution of these processes varies across different wetland community types. We assessed the resilience of wetlands to sea-level rise along a transitional gradient from tida...
Article
Full-text available
Downed woody debris is an important component of the forest floor, responsible for long-term storage of nutrients in many ecosystems. In large floodplain forests of the southeastern United States, wood loads are relatively low, suggesting these landscapes may promote rapid decomposition and nutrient turnover rates. The goals of this study were to i...
Article
Tidal freshwater wetlands are one of the most vulnerable ecosystems to climate change and rising sea levels. However salinification within these systems is poorly understood, therefore, productivity (litterfall, woody biomass, and fine roots) were investigated on three forested tidal wetlands [(1) freshwater, (2) moderately saline, and (3) heavily...
Article
Microbial fuel cell (MFC) technology has shown great potential for harvesting energy from waste organic materials. Here, we explored the potential of MFC-based electricity generation from forest detritus, a large untapped biomass pool. Electricity generation from in situ MFCs and relevant environmental parameters (i.e., carbon sources and concentra...
Article
Full-text available
Forests comprise approximately 37% of the terrestrial land surface and influence global water cycling. However, very little attention has been directed toward understanding environmental impacts on stand water use (S) or in identifying rates of S from specific forested wetlands. Here we use sapflow techniques to address two separate, but linked obj...
Conference Paper
Full-text available
Coastal forested wetland swamps are sentinel sites for salinity intrusions associated with large tidally-influenced or storm-driven incursions of estuarine waters that may also indicate rising sea levels associated with climate change. A coastal freshwater forested wetland in coastal South Carolina has experienced dieback of freshwater forested wet...
Article
Full-text available
Alterations to Louisiana’s coastal landscape during the last 200 years have resulted in major changes to the natural hydrologic regime. Hurricane and tornado winds further impact coastal forests by exacerbating conditions that affect community structure, growth, and regeneration. Twenty-three years of study of forested wetlands in the Lake Verret w...
Data
Full-text available
Louisiana’s coastal wetland forests are of tremendous economic, ecological, cultural, and recreational value to residents of Louisiana, the people of the United States, and the world. Although some two million acres of forested wetland occur throughout Louisiana, over half are in the coastal parishes. Large-scale and localized alterations of proces...
Article
QuestionsWhat are the general tree communities found in tidal freshwater swamps along four large coastal rivers in the southeastern United States (US)? How do these communities compare to other tidal freshwater swamps in the US and South America?LocationsTidal floodplains of major rivers along the Atlantic and Gulf coasts of the southeastern US: Sa...
Article
Little is known of the ability of baldcypress (Taxodium distichum (L.) L.C. Rich.) in a suppressed sub-canopy position to respond to increases in light. We measured 3 years of diameter growth response of long-suppressed baldcypress saplings to canopy gap creation in a hydrologically altered, water tupelo-dominated backswamp of the lower Roanoke Riv...
Article
Full-text available
In the late nineteenth century and twentieth century, there was considerable interest and activity to develop the United States for agricultural, mining, and many other purposes to improve the quality of human life standards and prosperity. Most of the work to support this development was focused along disciplinary lines with little attention focus...
Article
Full-text available
Seasonally flooded, freshwater cypress-tupelo wetlands, dominated by baldcypress (Taxodium distictum), water tupelo (Nyssa aquatica), and swamp tupelo (Nyssa sylvatica var. biflora) are commonly found in coastal regions of the southeastern United States. These wetlands are threatened due to climate change, sea level rise, and coastal urban developm...
Article
Full-text available
Hummock and hollow microtopography is pervasive in tidal freshwater swamps. Many tree species grow atop hummocks significantly more than in hollows, leading to the hypothesis that hummocks provide preferred locations for maximizing physiological proficiency of inhabiting trees that experience repeated flooding. We used thermal dissipation probes to...
Article
Full-text available
Many tidally influenced freshwater forested wetlands (tidal swamps) along the south Atlantic coast of the USA are currently undergoing dieback and decline. Salinity often drives conversion of tidal swamps to marsh, especially under conditions of regional drought. During this change, alterations in nitrogen (N) uptake from dominant vegetation or tim...
Conference Paper
Background: Arthropod-borne zoonotic diseases vary geographically and occur in significant clusters. Spatio-temporal modeling of these diseases is often conducted at the county level which can mask smaller isolated high risk areas. Administrative medical claims data aggregated to the ZIP code level could improve disease surveillance activities whil...
Chapter
Full-text available
Freshwater forested wetlands commonly occur in the lower Coastal Plain of the southeastern US with baldcypress (Taxodium distichum [L.] L.C. Rich.) and water tupelo (Nyssa aquatica L.) often being the dominant trees. Extensive anthropogenic activities combined with eustatic sea-level rise and land subsidence have caused widespread hydrological chan...
Article
Full-text available
Zoonotic diseases can be transmitted via an arthropod vector, and disease risk maps are often created based on underlying associative factors within the surrounding landscape of known occurrences. A limitation however is the ability to map disease risk at a meaningful geographic scale, and traditional regression modeling approaches may not always b...
Article
Considered separately, notifiable disease registries and medical claims data have certain advantages (e.g., consistent case definitions and electronic records, respectively) and limitations (e.g., incomplete reporting and coding errors, respectively) within disease outbreak research. Combined however, these data could provide a more complete source...
Conference Paper
Background/Question/Methods Tidal freshwater forested wetlands occupy the interface of terrestrial and marine systems, providing vital services including storm abetment and carbon storage. Due to their discrete placement, they are some of the most vulnerable wetlands to climatic impacts such as sea level rise; however research on these systems is...
Article
Full-text available
Objective To determine what, if any, opportunity exists in using administrative medical claims data for supplemental reporting to the state infectious disease registry system. Materials and methods Cases of five tick-borne (Lyme disease (LD), babesiosis, ehrlichiosis, Rocky Mountain spotted fever (RMSF), tularemia) and two mosquito-borne diseases (...
Article
Full-text available
Tidal freshwater wetlands are sensitive to sea level rise and increased salinity, although little information is known about the impact of salinification on nutrient biogeochemistry in tidal freshwater forested wetlands. We quantified soil nitrogen (N) and phosphorus (P) mineralization using seasonal in situ incubations of modified resin cores alon...
Conference Paper
Zoonotic diseases can be transmitted via an arthropod vector and disease risk maps are often based on underlying associative factors within the surrounding landscape of known occurrences. A major limitation is the ability to track disease incidence at a meaningful geographic scale and traditional linear modeling approaches may not always be appropr...
Conference Paper
Notifiable diseases require regular and timely reporting of diagnosed cases to aid in prevention and control. However, manual reporting can be burdensome, incomplete and delayed. Managed care organizations (MCO) could play a major role in supporting surveillance efforts and spatio-temporal tracking of infectious zoonotic diseases. The objective is...
Article
Full-text available
Aims In recent years, there has been an increased interest in examining changes in forest systems in response to drought, flooding, hurricanes and climate change. In the southern United States, forested wetlands are of special interest because of the extent of these forests. Coastal plain forested wetlands are among the most vulnerable to these cli...
Article
Full-text available
Relative to effects of flooding, little is known about the influence of hydrology-nutrient interactions on aboveground net primary production (NPP) in forested wetlands. We found that nutrient circulation and NPP were closely related along a complex physical, chemical, and hydrologic gradient in a bottomland hardwood forest with four distinct commu...
Article
Full-text available
Digital vegetation is the computerized representation, with either virtual images or animations, of vegetation types and conditions based on current measurements or ecological models. Digital vegetation can be useful in evaluating past, present, or future land use; changes in vegetation linked to climate change; or restoration eff orts. Digital veg...
Technical Report
Full-text available
This report is the outcome of a science panel review sponsored by Collier Resources Company (CRC) and administered by the Everglades Foundation to provide a science-based assessment of impacts from oil and gas (O&G) activities in Big Cypress National Preserve (BCNP). A team of experts, independently selected by the Everglades Foundation, Inc. (EFI)...
Article
Stand density indices (SDIs) are surrogate measures of site occupancy useful for developing quantitative management tools for forest types that have not been extensively studied. For example, there has been little research of growth-density relationships for baldcypress (Taxodium distichum [L.] L.C. Rich.). We used published data, forest inventory...
Article
Tidal freshwater forests in coastal regions of the southeastern United States are undergoing dieback and retreat from increasing tidal inundation and saltwater intrusion attributed to climate variability and sea-level rise. In many areas, tidal saltwater forests (mangroves) contrastingly are expanding landward in subtropical coastal reaches succeed...
Article
Full-text available
Tidal freshwater swamps, occuping the upper reaches of tidal influence, begin active conversion to oligohaline marsh at salinity levels as low as 2 g/I. The most imminent climate-induced threat to existing tree communities in tidal swamps is increased salinization resulting from sea level rise, a condition exacerbated by drought. Baldcypress is the...
Article
Full-text available
Tidal freshwater forested wetlands occupy a relatively narrow range, occurring where wind and lunar tides interact with coastal river systems, causing freshwater flooding onto the floodplain. A prominent component of this wetland type is hummock and hollow microtopography. Tidal freshwater forested wetlands along the Savannah River were differentia...
Conference Paper
Background/Question/Methods Over the next century rising sea level will move the land/sea interface inland, exposing coastal ecosystems to increasing tidal influence including increased flooding frequency and salinity. We want to understand how these environmental changes will modify coastal forest structure, productivity and carbon cycling. Many...
Article
Full-text available
This report documents changes in forest structure and growth potential of dominant trees in salt-impacted tidal and non-tidal baldcypress wetlands of the southeastern United States. We inventoried basal area and tree height, and monitored incremental growth (in basal area) of codominant baldcypress (Taxodium distichum) trees monthly, for over four...
Article
Full-text available
Little is known about the effectiveness of mangroves in suppressing water level heights during landfall of tropical storms and hurricanes. Recent hurricane strikes along the Gulf Coast of the United States have impacted wetland integrity in some areas and hastened the need to understand how and to what degree coastal forested wetlands confer protec...
Conference Paper
Full-text available
Non-native wild pig (Sus scrofa) disturbance was evaluated over three years (2000-2003) in fixed 1,000 m 2 plots at Congaree National Park in South Carolina. Hog disturbance (mainly rooting) averaged across all years was more abundant in cypress-tupelo swamp (19% total ground disturbance) compared to bottomland hardwoods (9%). In small linear cypre...