Wetland Vegetation Response to Groundwater Pumping and Hydrologic Recovery

AbstractAn investigation of wetland vegetation response to groundwater alteration was conducted at the J.B. Starkey Wilderness Park, a large municipal wellfield in the area of west Florida, USA. Decades of historic groundwater withdrawal had created a gradient of impacted wetlands on the wellfield, after which time the groundwater pumping rates were reduced. Nineteen cypress dome wetlands were grouped, based on their hydrologic histories, as either most-altered (least inundation), marginally-altered (intermediate inundation), or least-altered (near-normal inundation). Annual species–level monitoring data were used to evaluate understory plant community response to the hydrologic recovery that resulted from reduced groundwater pumping. Species richness, cover, prevalence index (PI), and species importance percentages were assessed during pre- (2005–2007) and post- (2012–2014) hydrologic recovery periods. The vegetation in marginally- and most-altered wetlands responded to hydrologic recovery with increased species richness and lower PI values (i.e., greater hydrophytic character). However, species importance percentages indicated greater variation in the recovery of most-altered wetlands, where species composition often remained different from least-altered wetlands. Although reductions in groundwater pumping caused sufficient passive hydrologic recovery to elicit a vegetation response, further reductions and/or more time may be needed before the vegetation of some altered wetlands can become comparable to that of least-impacted wetlands.

Download Full-text

Seeking optimal groundwater pumping strategies at Pinggu District in Beijing, China

Journal of Hydroinformatics ◽

10.2166/hydro.2012.006 ◽

2012 ◽

Vol 15 (2) ◽

pp. 607-619 ◽

Cited By ~ 2

Author(s):

A. L. Yang ◽

G. H. Huang ◽

X. S. Qin ◽

L. Li ◽

W. Li

Keyword(s):

Groundwater Management ◽

Fuzzy Optimization ◽

Cost Effective ◽

Optimization Method ◽

Chance Constrained Programming ◽

Groundwater Pumping ◽

Simulation And Optimization ◽

Study Results ◽

Pumping Rates ◽

Beijing China

A simulation-based fuzzy optimization method (SFOM) was proposed for regional groundwater pumping management in considering uncertainties. SFOM enhanced the traditional groundwater management models by incorporating a response matrix model (RMM) into a fuzzy chance-constrained programming (FCCP) framework. RMM was used to approximate the input–output relationship between pumping actions and subsurface hydrologic responses. Due to its explicit expression, RMM could be easily embedded into an optimization model to help seek cost-effective pumping solutions. A groundwater management case in Pinggu District of Beijing, China, was used to demonstrate the method's applicability. The study results showed that the obtained system cost and pumping rates would vary significantly under different confidence levels of constraints satisfaction. The decision-makers could identify the best groundwater pumping strategy through analyzing the tradeoff between the risk of violating the related water resources conservation target and the economic benefit. Compared with traditional approaches, SFOM was particularly advantageous in linking simulation and optimization models together, and tackling uncertainties using fuzzy chance constraints.

Download Full-text

Do predaceous stoneflies and siltation affect the structure of stream insect communities colonizing enclosures?

Canadian Journal of Zoology ◽

10.1139/z85-226 ◽

1985 ◽

Vol 63 (7) ◽

pp. 1519-1530 ◽

Cited By ~ 62

Author(s):

Barbara L. Peckarsky

Keyword(s):

New York ◽

Species Richness ◽

Prey Species ◽

Species Abundance ◽

Benthic Invertebrate ◽

Taxonomic Composition ◽

Community Response ◽

Insect Communities ◽

Composite Effect ◽

Benthic Invertebrate Community

Experiments in Colorado and New York streams assessed the effects of predaceous stoneflies on benthic invertebrate community establishment in enclosures providing uncolonized habitat. Aspects of prey community structure measured were density, species richness, relative species abundance, and body size. Unexpected inorganic sediment deposition allowed evaluation of direct effects on Colorado stream benthos and indirect effects on predation. Predaceous perlids and perlodids consistently reduced the density and, therefore, rate of prey community establishment in enclosures. Although New York perlids disproportionately reduced densities of some prey species, Colorado stoneflies caused nonsignificant declines in individual prey species densities, the composite effect of which was a significant whole-community response. Predators did not affect prey species richness nor change the taxonomic composition (species additions or deletions) of communities colonizing enclosures. However, the relative abundance of prey taxa differed significantly between cages with and without predators. Most species showed no size differences between individuals colonizing enclosures with predators and those colonizing control enclosures, with a few interesting exceptions. The deposition of silt eliminated the predator effects on prey density, as well as directly causing significant reductions in many Colorado benthic populations. This result demonstrates that abiotic disturbances can periodically override the effects of predation on stream insect communities colonizing enclosures.

Download Full-text

Wetland vegetation response to record-high Lake Ontario water levels

Journal of Great Lakes Research ◽

10.1016/j.jglr.2020.10.013 ◽

2020 ◽

Author(s):

Ian M. Smith ◽

Giuseppe E. Fiorino ◽

Greg P. Grabas ◽

Douglas A. Wilcox

Keyword(s):

Lake Ontario ◽

Wetland Vegetation ◽

Water Levels ◽

Vegetation Response

Download Full-text

Wildland fire effects on understory plant communities in two fire-prone forests

Canadian Journal of Forest Research ◽

10.1139/x07-118 ◽

2008 ◽

Vol 38 (1) ◽

pp. 133-142 ◽

Cited By ~ 29

Author(s):

Daniel C. Laughlin ◽

Peter Z. Fulé

Keyword(s):

Species Richness ◽

Ponderosa Pine ◽

Wildland Fire ◽

Plant Cover ◽

Plant Species Richness ◽

Fire Effects ◽

Surface Fire ◽

Total Species Richness ◽

Understory Plant ◽

Understory Plant Communities

Our understanding of wildland fire effects on understory plant communities is limited because of a lack of repeated measurements before and after lightning-ignited fires. We examined vegetation responses to a surface fire in a ponderosa pine forest and a mixed-severity fire in a spruce–fir–aspen forest using before–after, control–impact (BACI) study designs. We hypothesized that the surface fire would stimulate plant species richness and minimally alter community composition, but that the mixed-severity fire would decrease richness and significantly alter composition. In ponderosa pine forests, total species richness and plant cover increased slightly because of annual and biennial forb and grass establishment in soils where duff layers were reduced by the surface fire. In spruce–fir–aspen forests, total species richness and plant cover were similar in burned and unburned forests after 2 years, although annual and biennial forbs and graminoids increased significantly in the burned area. Plant community composition was altered by both fires. Wildfires may indirectly influence the understory plant community through the mediating effects of overstory basal area and litter depth. Fire effects on plant species richness and cover were weaker than effects due to environmental factors. Managers should anticipate increases in both native and non-native ruderal species following landscape-scale fires.

Download Full-text

Palustrine forested wetland vegetation communities change across an elevation gradient, Washington State, USA

PeerJ ◽

10.7717/peerj.8903 ◽

2020 ◽

Vol 8 ◽

pp. e8903

Author(s):

Nate Hough-Snee

Keyword(s):

Plant Species ◽

Plant Communities ◽

Indicator Species ◽

Elevation Gradient ◽

Forested Wetlands ◽

Wetland Vegetation ◽

Forested Wetland ◽

Wetland Plant ◽

Wetland Plant Communities ◽

Understory Plant

Background Forested wetlands support distinct vegetation and hydrology relative to upland forests and shrub-dominated or open water wetlands. Although forested wetland plant communities comprise unique habitats, these ecosystems’ community structure is not well documented in the U.S. Pacific Northwest. Here I surveyed forested wetland vegetation to identify changes in community composition and structure across an elevation gradient that corresponds to flooding stress, asking: (1) How do forested wetland plant communities change across an elevation gradient that corresponds to flood frequency and duration? (2) At what relative elevations do different plant species occur within a wetland? Methods I measured overstory tree basal area and structure and understory vascular plant composition in three zones: wetland buffers (WB) adjacent to the wetland, an upper wetland (UW) extent, and a lower wetland (LW) extent, surveying individual trees’ root collar elevation relative to the wetland ordinary high-water mark (OHWM). I estimated understory plant species abundance in sub-plots and surveyed these plots’ height above the OHWM. I used non-metric multidimensional scaling ordination to identify patterns in vegetation communities relative to wetland elevation, and tested for compositional differences between the WB, UW and LW zones using PERMANOVA. I calculated overstory and understory indicator species for each wetland zone using indicator species analysis. Results Forest overstory composition changed across the elevation gradient, with broad-leaved trees occupying a distinct hydrologic niche in low-lying areas close to the OHWM. Conifer species occurred higher above the OHWM on drier microsites. Pseudotsuga menziesii (mean elevation = 0.881 m) and Tsuga heterophylla (mean elevation = 1.737 m) were overstory indicator species of the WB, while Fraxinus latifolia (mean elevation = 0.005 m) was an overstory indicator for the upper and lower wetland. Understory vegetation differed between zones and lower zones’ indicator species were generally hydrophytic species with adaptations that allow them to tolerate flooding stress at lower elevations. Average elevations above the OHWM are reported for 19 overstory trees and 61 understory plant species. By quantifying forested wetland plant species’ affinities for different habitats across an inundation gradient, this study illustrates how rarely flooded, forested WB vegetation differs from frequently flooded, LW vegetation. Because common management applications, like restoring forested wetlands and managing wetland responses to forest harvest, are both predicated upon understanding how vegetation relates to hydrology, these data on where different species might establish and persist along an inundation gradient may be useful in planning for anticipated forested wetland responses to restoration and disturbance.

Download Full-text

Hybridization among foundation tree species influences the structure of associated understory plant communities

Botany ◽

10.1139/b11-006 ◽

2011 ◽

Vol 89 (3) ◽

pp. 165-174 ◽

Cited By ~ 16

Author(s):

L. J. Lamit ◽

T. Wojtowicz ◽

Z. Kovacs ◽

S. C. Wooley ◽

M. Zinkgraf ◽

...

Keyword(s):

Species Richness ◽

Plant Communities ◽

Structural Equation ◽

Evolutionary Ecology ◽

Experimental System ◽

Common Garden ◽

Equation Modeling ◽

Understory Plant ◽

Tree Genetics ◽

Understory Plant Communities

Understanding how genetic identity influences community structure is a major focus in evolutionary ecology, yet few studies examine interactions among organisms in the same trophic level within this context. In a common garden containing trees from a hybrid system (Populus fremontii S. Wats. × Populus angustifolia James), we tested the hypothesis that the structure of establishing understory plant communities is influenced by genetic differences among trees and explored foliar condensed tannins (CTs) and photosynthetically active radiation (PAR) as mechanisms. Several findings support our hypothesis: (i) Understory biomass and cover increase along the genetic gradient from P. angustifolia to P. fremontii. (ii) Along the same hybridization gradient, species richness decreases and species composition shifts. (iii) Populus foliar CT concentrations and PAR decrease from P. angustifolia to P. fremontii. (iv) Understory species richness increases with foliar CTs; however, biomass, cover, and composition show no relationship with CTs, and no understory variables correlate with PAR. (v) Structural equation modeling suggests that foliar CTs are a primary mechanism linking overstory tree genetics with understory richness. Using an experimental system dominated by naturally colonizing exotic species, this study demonstrates that a genetic gradient created by tree hybridization can influence understory plants.

Download Full-text