Radar mapping, archaeology, and ancient land use in the Maya lowlands

Data from the use of synthetic aperture radar in aerial survey of the southern Maya lowlands suggest the presence of very large areas drained by ancient canals for the purpose of intensive cultivation. Preliminary ground checks in several very limited areas confirm the existence of canals and raised fields. Excavations and ground surveys by several scholars provide valuable comparative information. Taken together, the new data suggest that Late Classic period Maya civilization was firmly grounded in large-scale and intensive cultivation of swampy zones

Bacon\u27s Swamp- Ghost of a Central Indiana Natural Area Past

Bacon’s Swamp was identified in the 1920s as a ca. 12 ha glacial kettle lake bog system at the southernmost limits of these habitats in Indiana. Located just 9.6 km from the center of Indianapolis, the site was all but destroyed in the mid-20th century by urban expansion. Prior to habitat conversion at the site, Bacon’s Swamp was a frequent location for Butler University ecology class field trips and student research projects. Herbarium specimens and published inventory records allow for analysis of the historical vegetation of Bacon’s Swamp using modern techniques. Floristic Quality Assessment applied to these historical records reveals Bacon’s Swamp was a regionally significant natural area, with a native Floristic Quality Index (FQI) value of 60 and a mean native Conservation Coefficient value of 4.2. Little of this unusual, high-quality habitat remains. A 2010 botanical inventory at the site documents decline in habitat with the loss of species that have a fidelity to high-quality habitat, with a corresponding drop in FQI to 20 and the addition of invasive non-native plants. Re-analysis of Bacon’s Swamp historical flora supports the view that it was a significant wetland natural area and floristically unique in Central Indiana

The ecology of Atlantic white cedar wetlands: a community profile

This monograph on the ecology of Atlantic white cedar wetlands is one of a series of U.S. Fish and Wildlife Service profiles of important freshwater wetland ecosystems of the United States. The purpose of the profile is to describe the extent, components, functioning, history, and treatment of these wetlands. It is intended to provide a useful reference to relevant scientific information and a synthesis of the available literature. The world range of Atlantic white cedar (Chamaecyparis thyoides) is limited to a ribbon of freshwater wetlands within 200 km of the Atlantic and Gulf coasts of the United States, extending from mid-Maine to mid-Florida and Mississippi. Often in inaccessible sites and difficult to traverse, cedar wetlands contain distinctive suites of plant species. Highly valued as commercial timber since the early days of European colonization of the continent, the cedar and its habitat are rapidly disappearing. This profile describes the Atlantic white cedar and the bogs and swamps it dominates or codominates throughout its range, discussing interrelationships with other habitats, putative origins and migration patterns, substrate biogeochemistry, associated plant and animal species (with attention to those that are rare, endangered, or threatened regionally or nationally), and impacts of both natural and anthropogenic disturbance. Research needs for each area are outlined. Chapters are devoted to the practices and problems of harvest and management, and to an examination of a large preserve recently acquired by the USFWS, the Alligator River National Wildlife Refuge in North Carolina

The Vegetation of Three Sphagnum-dominated Basin-type Bogs in Northeastern Ohio

Author Institution: Division of Natural Sciences, Cuyahoga Community College and Department of Biological Sciences, Kent State UniversityVegetation and selected ground water characteristics were examined for three closely proximate basin-type bogs in northeastern Ohio. These peatlands exhibit zonation, with a low shrub zone dominated by Chamaedaphne calyculata (Frequency-Presence Index [FPI] 4433) and Decodon verticillatus (FPI 5400) adjacent to and invading the open water. A tall shrub zone, extending aproximately 5 to 10 m to the exterior of the low shrub zone, is dominated by Vaccinium corymbosum (FPI 5533), Gaylussacia baccata (FPI 3133), andNemopanthus mucronatus (FPI 2200). Extending for the next 5 -10 m is a tree zone, dominated by Larix laricina (FPI 800), Betula alieghaniensis (FPI 198), andNyssa sylvatica (FPI 77). Sphagnum recurvum (sensu lato) (FPI 6500) forms a more or less continuous mat throughout the bogs. The vegetation of the three peatlands is similar, with similarity indices (c) ranging from 0.59 to 0.67. Based on pH, conductivity and Ca and Mg ion concentrations, these peatlands are semi-ombrotrophic to weakly minerotrophic. These communities, located near the glacial boundary, represent northern peatlands at the southern edge of glaciation

The middle Waikato Basin and hills

The middle Waikato (or Hamilton) Basin is a roughly oval-shaped depression more than 80 km north to south and more than 40 km wide. The basin, except in the south, is almost completely surrounded by ranges up to 300 m high, broken by only a few gaps. In the south the basin floor rises gradually and merges with the dissected plateaux of the King Country

Successional dynamics of a 35 year old freshwater mitigation wetland in southeastern New Hampshire

The long-term ecological success of compensatory freshwater wetland projects has come into question based on follow-up monitoring studies over the past few decades. Given that wetland restoration may require many years to decades to converge to desired outcomes, long-term monitoring of successional patterns may increase our ability to fully evaluate success of wetland mitigation projects or guide adaptive management when needed. In Portsmouth, New Hampshire a 4 ha wetland was constructed in an abandoned gravel quarry as off-site compensatory mitigation for impacts to a scrub-shrub swamp associated with property expansion. Building upon prior evaluations from 1992 and 2002, we conducted a floral survey in 2020 to compare results with prior surveys to document vegetation successional trends over time. In addition, we monitored the avian community throughout the growing season as a measure of habitat quality. The plant community mirrored documented successional trends of freshwater wetland restoration projects as native hydrophytes dominated species composition. Plant species composition stabilized as the rate of turnover, the measurement of succession, declined by nearly half after 17 years. Researchers should consider long-term monitoring of specific sites to better understand successional patterns of created wetlands as we documented long time frames required for the development of scrub-shrub swamps, red maple swamps, and sedge meadows. High species richness was attributed to beaver activity, topographic heterogeneity from Carex stricta tussocks, and the seed bank from the application of peat from the original wetland. Habitat heterogeneity of open water, herbaceous cover, and woody vegetation supports a diverse avian community including 11 wetland dependent species. Although the mitigation project has not created the full area of lost scrub-shrub swamp after 35 years, it has developed a structurally complex habitat and diverse avian community that effectively provides the functions and values of the impacted system

The Discovery of Old Fort Congaree

https://scholarcommons.sc.edu/archanth_books/1192/thumbnail.jp

Introduction and Establishment of Cyrtobagous salviniae Calder and Sands (Coleoptera: Curculionidae) for the Control of Salvinia minima Baker (Salviniaceae), and Interspecies Interactions Possibly Limiting Successful Control in Louisiana

Common salvinia, Salvinia minima Baker, is a floating aquatic invasive macrophyte that obstructs waterways and causes problems in wetlands across Louisiana and Texas. The salvinia weevil, Cyrtobagous salviniae Calder and Sands, has been released in over 14 countries around the world for the biological control of Salvinia spp. We successfully monitored the introduction and establishment of C. salviniae on S. minima in southern Louisiana between 2006 and 2010. Cyrtobagous salviniae significantly lowered the biomass of S. minima and increased the number of terminal buds damaged but had no significant impact on pH, dissolved oxygen, conductivity, surface temperature, percent of surface coverage, or percent of the mat that was green. Restricting access to the S. minima mat from the red imported fire ant, Solenopsis invicta Buren, significantly increased the number of C. salviniae, suggesting that S. invicta should be controlled where possible to maximize the success of the biological control program. While collecting arthropods associated with S. minima, we identified 5,773 individuals that represent 176 species within 62 families and seven orders including four currently undescribed species, and seven species of semi]aquatic Curculionidae (five of which have been used in biological control programs). We collected higher numbers of taxa than previous studies, but most of the species are previously known as hydro] or hygrophilous, indicating the differences may have been due to collection methods. Collecting locations were clustered into five groups based on secondary aquatic vegetation and evaluated by cluster for community composition and similarity. We found no support for the spatial heterogeneity hypothesis, as our most diverse community is one of the least spatially complex, suggesting other factors are affecting community composition. Findings included successful establishment of C. salviniae, recommendation to control S. invicta around C. salviniae release sites, improved methods for collecting insects associated with floating aquatic vegetation, and contributions to the knowledge of the biodiversity of Louisianafs backwater swamps. In addition to providing new information on interactions between C. salviniae and S. minima, these studies will be useful in designing,evaluating, and monitoring releases of other biological control agents on floating aquatic macrophytes