Energy and water balance response of a vegetated wetland to herbicide treatment of invasive Phragmites australis

JOURNAL OF HYDROLOGY

卷:539

Article

Mykleby, Phillip M.^1,6  Lenters, John D.²  Cutrell, Gregory J.²  Herrman, Kyle S.³  Istanbulluoglu, Erkan⁴  Scott, Durelle T.⁵  Twine, Tracy E.⁶  Kucharik, Christopher J.^7,8  Awada, Tala¹  Soylu, Mehmet E.⁹  Dong, Bo¹⁰ 

[1] Univ Nebraska, Sch Nat Resources, Lincoln, NE USA

[2] LimnoTech, Ann Arbor, MI USA

[3] Univ Wisconsin, Coll Nat Resources, Stevens Point, WI 54481 USA

[4] Univ Washington, Civil & Environm Engn, Seattle, WA 98195 USA

[5] Virginia Tech, Dept Biol Syst Engn, Blacksburg, VA USA

[6] Univ Minnesota, Dept Soil Water & Climate, 439 Borlaug Hall,1991 Upper Buford Circle, St Paul, MN 55108 USA

[7] Univ Wisconsin, Dept Agron, Madison, WI USA

[8] Univ Wisconsin, Nelson Inst Ctr Sustainabil & Global Environm, Madison, WI USA

[9] Meliksah Univ, Dept Civil Engn, Kayseri, Turkey

[10] SUNY Albany, Dept Atmospher & Environm Sci, Albany, NY 12222 USA

关键词: Energy balance;    Evapotranspiration;    Water balance;    Phragmites australis;    Wetland;    Agro-IBIS;   

DOI  :  10.1016/j.jhydrol.2016.05.015

来源: Elsevier

【 摘 要 】

The energy and water balance of a Phragmites australis dominated wetland in south central Nebraska was analyzed to assess consumptive water use and the potential for water savings as a result of vegetation eradication via herbicide treatment. Energy balance measurements were made at the field site for two growing seasons (treated and untreated), including observations of net radiation, heat storage, and sensible heat flux, which was measured using a large-aperture scintillometer. Latent heat flux was calculated as a residual of the energy balance, and comparisons were made between the two growing seasons and with model simulations to examine the relative impacts of vegetation removal and climate variability. Observed ET rates dropped by roughly 32% between the two growing seasons, from a mean of 4.4 +/- 0.7 mm day(-1) in 2009 (with live vegetation) to 3.0 +/- 0.8 mm day(-1) in 2010 (with dead P. australis). These results are corroborated by the Agro-IBIS model simulations, and the reduction in ET implies a total water savings of 245 mm over the course of the growing season. The significant decreases in ET were accompanied by a more-than-doubling of sensible heat flux, as well as a 60% increase in heat storage due to decreased LAI. Removal of P. australis was also found to cause measurable changes in the local micrometeorology at the wetland. Consistent with the observed increase in sensible heat flux during 2010, warmer, drier, windier conditions were observed in the dead, P. australis section of the wetland, compared to an undisturbed section of live, native vegetation. Modeling results suggest that the elimination of transpiration in 2010 was partially offset by an increase in surface evaporation, thereby reducing the subsequent water savings by roughly 60%. Thus, the impact of vegetation removal depends on the local climate, depth to groundwater, and management decisions related to regrowth of vegetation. (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

Free