The effect of water level management on the soils and vegetation of two coastal Louisiana marshes

被引:5
作者
Flynn K.M.
Mendelssohn I.A. [1 ]
Wilsey B.J. [2 ]
机构
[1] Wetland Biogeochemistry Institute, Ctr. Coast., Ener. Environ. Rsrc., Louisiana State University, Baton Rouge
[2] Grass. Soil and Water Res. Lab., Temple, TX 76502
关键词
Burning; Eh; Hydrologic alterations; Levees and water control structures; Plant CO[!sub]2[!/sub] exchange rates; Spartina patents; Structural marsh management; Sulfide;
D O I
10.1023/A:1008486500173
中图分类号
学科分类号
摘要
Wetland degradation and loss is the result of a combination of natural causes and anthropogenic activities and is a serious problem in coastal Louisiana, where approximately 80% of the total US coastal wetland loss since the 1930's has occurred. One method currently used to address this wetland loss problem is structural marsh management, which is the use of levees and water control structures to control hydroperiod. The effects of structural marsh management on two managed marshes in Southern Louisiana (Unit 4 of the Rockefeller Wildlife Refuge and the Fina LaTerre Mitigation Bank) were evaluated by comparing the soils and the dominant emergent marsh vegetation (Spartina patens) of the two managed marshes with those of two nearby unmanaged marshes. Soil redox potential, water depth, interstitial water sulfide concentration, salinity, NH4-N and elemental concentrations of Na, K, Ca, Mg, P, Fe and Zn were measured four times during 1989 which was a drawdown year. Net and total CO2 exchange rate, primary productivity, leaf area, stem density, and live, dead and total aboveground biomass were also measured. The managed marsh at Rockefeller had lower water levels, significantly less reduced surface and 15 cm deep soils and significantly lower interstitial sulfide concentrations and salinity levels. Na, K, Mg and Ca concentrations reflected the same pattern as salinity. Live aboveground biomass, primary productivity and leaf area were 3-4 times greater in the managed marsh. This indicates that marsh management improved soil conditions and provided an environment favorable to more vigorous plant growth. The management scheme at Fina LaTerre was also successful at maintaining lower water levels than in the adjacent unmanaged area. However, surface soils were more reduced and interstitial salinity higher, on average, in the managed marsh indicating generally poorer water circulation. Primary productivity was 50% less and stem density, leaf area, net CO2 and total CO2 exchange rates were significantly lower in the managed marsh, compared to the nearby reference marsh. Conditions in the managed marsh indicate that the management scheme was not successful at improving soil conditions when compared to those in the adjacent unmanaged marsh. This study indicates that structural marsh management is not the universal answer to problems faced by Louisiana's coastal wetlands, but may be of value in specific situations.
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页码:193 / 218
页数:25
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共 70 条
[51]  
Ponnamperuma F.N., The chemistry of submerged soils, Adv. Agron., 24, pp. 29-96, (1972)
[52]  
Redman F.H., Patrick W.H. Jr., Effect of submergence on several biological and chemical soil properties, LSU-Agri. Exp. Station Bull. No. 592, (1965)
[53]  
Rogers D.R., Rogers B.D., Herke W.H., Effects of a marsh management plan on fishery communities in coastal Louisiana, Wetlands, 12, pp. 53-62, (1992)
[54]  
Roman C.T., Niering W.A., Warren R.S., Salt marsh vegetation change in response to tidal restriction, Environ. Managmt., 8, pp. 141-150, (1984)
[55]  
Sage R.F., Pearcy R.W., The nitrogen use efficiency of C<sub>3</sub> and C<sub>4</sub> plants. II. Leaf nitrogen effects on the gas exchange characteristics of Chenopodium album and Amaranthus retroflexus, Plant Physiol., 84, pp. 959-963, (1987)
[56]  
SAS User's Guide: Statistics, (1985)
[57]  
Shew D.M., Linthurst R.A., Seneca E.D., Comparison of production computation methods in a southeastern North Carolina Spartina alterniflora salt marsh, Estuaries, 4, pp. 97-109, (1981)
[58]  
Simmering R.B., Craft B., Woodard J., Clark D., An evaluation of the Tenneco LaTerre mitigation bank management plan, Proceedings of a Symposium on Marsh Management in Coastal Louisiana: Effects and Issues, pp. 319-329, (1989)
[59]  
Steever E.Z., Warren R.S., Niering W.A., Tidal energy subsidy and standing crop production of Spartina alterniflora, Estuar., Coastal Mar. Sci., 4, pp. 473-478, (1976)
[60]  
Sweeney K.P., Cahoon D.R., Swan M., Wicker K., Day J.W. Jr., Evaluation of marsh management effectiveness: Analysis of habitat change, A Study of Marsh Management Practice in Coastal Louisiana, Volume III, Ecological Evaluation, 3, pp. 281-355, (1990)