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ABSTRACT/Structural marsh management, using levees and water-control structures, is used in the coastal zone for many objectives, for example, to reduce marsh loss, to enhance waterfowl habitat, to revegetate open-water areas, and to reduce saltwater intrusion. The literature was evaluated to categorize structural marsh management and to determine some of its effects on fishes and crustaceans. Structural marsh management had positive effects on standing stock of most resident organisms and negative effects on marine-transient organisms. Emigration was negatively affected for both resident and marine-transient organisms. Techniques such as opening structures at critical migration times, designing structures that offer the greatest management flexibility, and using structures to create a flow-through system could reduce these impacts. More effort should be put into monitoring managed areas to determine if the objectives are being met and to evaluate the effects on fishes and crustaceans. Although frequent manipulation could reduce these impacts, the costs and problems incurred may outweigh the anticipated benefits.Structural marsh management, using levees and water-control structures, has been used to control water levels in the coastal zone for many years. The objectives of water control in coastal marshes are quite varied and include reducing extreme water level fluctuations, preventing saltwater intrusion, manipulating water levels, reducing coastal erosion, minimizing turbidity, stabilizing salinity, revegetating shallow mudflat areas, enhancing growth of desirable vegetation, enhancing waterfowl habitat, decreasing saltmarsh mosquitoes, and improving human access. Many of these objectives are closely related; for example, reducing water-level and salinity fluctuations may enhance waterfowl habitat by increasing submerged vegetation.Much controversy exists over the use of marsh management among federal, state, and local agencies, as well as the various user groups. Considerable effort has been expended in recent years to understand the effects of marsh management on coastal fishes and crustaceans, as well as other aspects of the ecosystem.We will review the literature and (1) describe and categorize various structural marsh management techniques, (2) examine the literature for effects on

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The effectiveness of a marsh management plan, involving a seasonal drawdown of brackish and freshwater marshes, on fishery communities and salinity were examined. The plan goals of reducing salinities and increasing circulation were not achieved during the drawdown, but salinities were buffered, and circulation improved during the nondrawdown phase. Significantly more grass shrimp (Palaemonetes sp.), least killifish ( Heterandria forrnosa), western mosquitofish ( Gambusia affinis), and golden topminnow ( Fundulus chrysotus) were collected in the managed area. More marine-transient organisms, primarily gulf menhaden (Brevoortia patronus), blue crab (Callinectes sapidus), and striped mullet (Mugil cephalus) were collected in the unmanaged area. Salinities were significantly higher in the managed area during the drawdown but not during the nondrawdown period. Water levels in the managed area were less variable.

Research on the association between pubescence and psychosocial development is expanding, but comparative development of theoretical frameworks lags behind. To expand a dialogue on the use of dialectic theory for understanding adolescent development, this article presents an overview of the basic tenets of a dialectical perspective regarding development. One conceptualization of the dialectic process and a general portrait of the dialectics of physical development and appearance are offered to demonstrate how this theoretical perspective could be used to provide structure to current knowledge regarding research on pubescence. Specific attention is given to the meaning and utility of the contrast between congruence and discordance, tranquility and tension, and constructive and destructive reconciliation. Methodological challenges are briefly discussed