Stephen A. Forbes, Antecedent Wetland Ecologist?

Stephen A. Forbes (1844-1930) was an American ento- mologist/zoologist who was born, raised and largely educated in northern Illinois. He spent most of his profes- sional career as the director of the Illinois Natural History Survey and as a faculty member and administrator at the University of 1llinois. Early in his scientific career, he stud- ied fish and bird diets by examining the stomach contents of these animals. In 1887, he published his most famous and influential paper, The lake as a microcosm, which contains one of the earliest formulations of what came to be called the ecosystem. In this paper, Forbes describes a hy- pothetical isolated, small lake as being a microcosm that is in equilibrium. This equilibrium is the result of trophic in- teractions among the organisms in the microcosm that limit the sizes of both predator and prey populations. Forbes believed that natural selection was responsible for limiting the reproductive capacities of predators and prey. Although energy transfer among trophic levels is not the main focus of his paper, Forbes postulated that food (energy) is one of the main factors structuring ecosystems, but he did not explicitly discuss the energetics of his lake microcosm. Forbes\u27 microcosm is based on his studies of the shallow portions of small, glacial lakes in northern Illinois that were dominated by aquatic plants. Today his microcosm would be classified as a palustrine or lacustrine wetland

Succession in Wetlands: A Gleasonian Appraoch

A qualitative model of succession in freshwater wetlands is proposed, based on the life history features of the species involved. Three key life history traits can be used to characterize wetland species: life—span, propagule longevity, and propagule establishment requirements. By combining these three life history traits, 12 basic wetland life history types are recognized. For each life history type, the future state (presence only in the form of propagules in the seed bank, presence as adult plants, or complete absence) of each species type in a wetland can be predicted if environmental conditions change. Most of the information needed to apply this model to a particular wetland can be obtained by an examination of a wetland\u27s seed bank. Several examples of succesion in North American and African wetlands are presented to illustrate the application of the model

Assisting Nature: Ducks, “Ding” and DU

Jay Ding Darling (1876-1962) was a newspaper editorial cartoonist and duck hunter. Because of his pro-conservation cartoons, he had become one America’s most prominent conservationists by the early 1930s. Joseph P. Knapp (1864-1951) was a prominent businessman, philanthropist, conservationist, and duck hunter who, like Darling, had become concerned about the decline of waterfowl populations. Both worked to reverse this duck decline. Darling was appointed chief of the Bureau of Biological Survey in 1934 by President Franklin Roosevelt. During his short tenure as its chief (1934-1935), he focused the Bureau’s mission more on wildlife conservation and he oversaw the expansion of the national wildlife refuge system. In 1930, Knapp founded the More Game Birds in America Foundation. This Foundation through its waterfowl surveys documented that western Canada was the major breeding ground of ducks in North America. This resulted in the Foundation establishing Ducks Unlimited, Inc. in the US and Ducks Unlimited (Canada) in 1937. DU, Inc. would raise money, and DU (Canada) would spend this money in western Canada on wetland conservation and restoration projects. Both men helped to slow down the loss of wetlands by stressing the need for the public and private sectors to conserve and restore them as waterfowl habitat. They also shaped future wetland science by creating opportunities for the employment of wetland scientists

Antecedent Wetland Ecologists - German and Austrian in the Ninetieth Century

Please note that this is the first of a series in WSP. Many of the people, and even institutions, who influenced the development of the wetland science as a field have recently died or closed, and many other pioneering wetland scientists have retired or will soon retire. Given this, we would like to capture the early history of our science by getting the people who created it to write about their reasons for becoming wetland scientists and their contributions to the field. This series of articles will focus on two major topics: (1) the contributions of major scientists working in wetlands to the development of wetland science, and (2) the roles of major wetland institutions and organizations in the development of wetland science. Each article will highlight major advances, organizational and/or intellectual, that have shaped wetland science in the United States and around the world

Evaluating the effectiveness of restored wetlands for reducing nutrient losses from agricultural watersheds

Scientists examined the effectiveness of recent wetland restorations and land use conversions (set-asides) for reducing nutrients in agricultural runoff into the Iowa Great Lakes

The development of zonation in freshwater wetlands: an experimental approach

The development of a new emergent coenocline in an experimental wetland complex located in the Delta Marsh, Manitoba, Canada, was monitored for four years. The previous emergent coenocline, which consisted of bands of Scirpus lacustris, Typha glauca, Scolochloa festucacea and Phragmites austra/is, had been eliminated by flooding the complex for two years to 1 m above normal. Water level in the experimental complex then was drawndown for two years during which recruitment from the seed bank of all four emergents occurred along the elevation gradient. The complex was then reflooded for two years. Because of secondary dispersal of emergent seed by water currents, all four species had seed distributions that were more similar than would be predicted from their position along the previous coenocline. Most species had a maximum seed density at about 247. 5 m AMSL, the elevation at which water levels had been held for the previous 25 years, but one species (Phragmites) also had a second density peak at higher elevations. Differential germination of seeds along the elevation gradient then shifted the distribution of two species (Scirpus and Phragmites) downslope and of one (Scolochloa) upslope and did not affect that of the fourth (Typha). Mortality during the drawdown then shifted the distribution of three species (Scirpus, Typha, and Phragmites) downslope. In two cells in the complex that were reflooded to the normal water level, the distribution of two species (Scolochloa and Phragmites) was shifted upslope; that of the other two was unaffected. After having been reflooded for two years, the position of each species along the new coenocline was a result of a unique combination of factors (dispersal, germination, seedling mortality, adult mortality). Three of the species (Scirpus, Typha and Scolochloa) after two years of reflooding were found at elevations similar to where they had been found in the previous coenocline, but they did not yet form monodominant stands as they had previously. Phragmites was found at much lower elevations than previously, and a Phragmites dominated zone had not redeveloped

The Vegetation of Restored and Natural Prairie Wetlands

Thousands of wetland restorations have been done in the glaciated mid‐continent of the United States. Wetlands in this region revegetate by natural recolonization after hydrology is restored. The floristic composition of the vegetation and seed banks of 10 restored wetlands in northern Iowa were compared to those of 10 adjacent natural wetlands to test the hypothesis that communities rapidly develop through natural recolonization. Restoration programs in the prairie pothole region assume that the efficient‐community hypothesis is true: all plant species that can become established and survive under the environmental conditions found at a site will eventually be found growing there and/or will be found in its seed bank. Three years after restoration, natural wetlands had a mean of 46 species compared to 27 species for restored wetlands. Some guilds of species have significantly fewer (e.g., sedge meadow) or more (e.g., submersed aquatics) species in restored than natural wetlands. The distribution and abundance of most species at different elevations were significantly different in natural and restored wetlands. The seed banks of restored wetlands contained fewer species and fewer seeds than those of natural wetlands. There were, however, some similarities between the vegetation of restored and natural wetlands. Emergent species richness in restored wetlands was generally similar to that in natural wetlands, although there were fewer shallow emergent species in restored wetlands. The seed banks of restored wetlands, however, were not similar to those of natural wetlands in composition, mean species richness, or mean total seed density. Submersed aquatic, wet prairie, and sedge meadow species were not present in the seed banks of restored wetlands. These patterns of recolonization seem related to dispersal ability, indicating the efficient‐community hypothesis cannot be completely accepted as a basis for restorations in the prairie pothole region

Establishment of an experimental wetland research complex

The environmental impact of agrichemical contamination of surface and ground water is a special concern in the Midwest. Better chemical management alone will not sufficiently reduce negative impacts on the environment. Another strategy—restoring wetlands in agricultural watersheds to serve as sinks for these chemicals—holds additional promise for reducing this contamination

Vegetation, Peat Elevation and Peat Depth on Two Tree Islands in Water Conservation Area 3-A

Vegetation (species composition and cover abundance) and peat and bedrock elevations were sampled along multiple transects across the head, near tail and far tail of two tree islands (designated the North Island and South Island) in Water Conservation Area 3-A. The heads of both islands are underlain by topographic highs in the bedrock. The peat layer was thinnest on the heads and much thicker on the near tail and far tail. The thinner peat layer on the heads of tree islands suggests that there is a mechanism that limits the maximum elevation of a tree island. Altogether 84 and 51 species were found on North Island and South Island, respectively. The results of an agglomerative hierarchical cluster analysis indicated that there were 9 and 7 plant assemblages on North Island and South Island, respectively. Although sometimes dominated by different species, the 7 assemblages on South Island had ecologically equivalent counterparts on North Island. Three plant assemblages (dry forest, wet forest, forest-fem) dominated by trees and shrubs (Chrysolalanus icaco (coco plum), Myrica cerifera (wax myrtle), Salix caroliniana (Carolina willow), and Schinus terebinthiflolius (Brazilianpepper)) were found primarily on the heads of the islands, which had the highest peat and bedrock elevations, and sometimes on the adjacent near tail. Sawgrass (Cladiumjamaicense) dominated plant assemblages (sparse sawgrass, dense sawgrass, decadent sawgrass, sawgrass-cattail) and wet prairie (Eleocharis cellulosa Torr. and Panicum hemitomon Schult.) were found at lower peat elevations and slough assemblages (Bacopa caroliniana, Eleocharis cellulosa, Nymphaea odorata, Utricularia purpurea) were found at the lowest peat elevations. There generally was no clear-cut relationship between bedrock or peat elevations and the distribution of the various sawgrass and wet prairie assemblages

Vegetation Change and Seed Banks in Marshes: Ecological and Management Implications

Natural waterfowl habitat management (Weller 1981) involves the use of natural forces (e.g., water levels, muskrat activity) to develop a mosaic of native plant communities, i.e., a habitat complex. Such a complex is designed to provide the nutritional and structural requirements for not only waterfowl, but also for a large variety of migratory bird and nongame species (Fredrickson and Taylor 1982). Natural management is less costly, more permanent, more esthetically pleasing, and provides more resources for wildlife than do standard agronomic practices (Fredrickson and Taylor 1982). Because natural marsh management is primarily the application of ecological principles, the successful development of a habitat complex requires a conceptual grasp of vegetation dynamics and a detailed understanding of the biological and physical factors that produce vegetation changes in wetlands