Effects of Wetland Biodiversity

Executive Summary

Wetlands around the world are losing plant biodiversity.
Loss of plant biodiversity can impair the functioning of wetlands.
Wetlands with greater plant diversity may remove more pollutants, with greater year-to-year consistancy.

Conceptual Background

Major concern about ecosystem functioning is how can we establish a community with adequate stability and diversity and what could be the roles for each diverse community member. In order to establish diverse and functional ecosystem, we need to consider factors that could be directly or indirectly influence diversity and their functions. Biodiversity is directly associated with production, If there is no biodiversity (eg. no plants), there is no ecosystem functioning (eg. no production). There are three major aspects to be considered for maintaining stable or sustainable ecosystem in ecosystem functioning.

1. Ecosystem properties
It basically includes both sizes of compartments such as pools of materials (carbon or organic matter) and rate of process (fluxes of materials and energy among compartments). In other word, it represents to summary of the various pools and fluxes and also to ecosystem goods and services as well (Hooper et al., 2005). Ecosystem properties exists variation based on types of ecosystems and their levels or rates of variability, so it does not inherently refer to "good" or "bad".

2. Ecosystem goods
It includes goods that are directly marketable such as foods, construction materials, medicines, wild types breeders for domestic plants and animals, gene products for biotechnology, tourism, etc.

3. Ecosystem services
It includes those properties that are either directly or indirectly benefit human endeavors such as maintaining hydrological cycles, regulating climates, cleaning air and water, maintaining atmospheric composition, pollination, soil genesis and storing and cycling of nutrients. Previous studies demonstrate that loss of biodiversity, in addition to loss of genetic resources, loss of productivity, loss of ecosystem buffering against ecological perturbation, and loss of aesthetic and commercially valuable resources, may alter or impair the services that ecosystem provide (Naeem et al., 1999a). However, different ecosystem processes respond differently to loss of biodiversity providing some support for several hypotheses that were proposed currently in terms of ecosystem functioning. Specifically, the loss of plant biodiversity leads to the reduction in the ability of ecosystem to fix carbon dioxide produced naturally or by anthropogenic activities. Two influential studies by Tilman and collegues under biodiversity-functioning on plant diversity and plant production increase the visibility of biodiversity and ecosystem functioning research.

Various hypotheses proposed in terms of ecosystem consequences due to loss of biodiversity are categorized into three major classes based on shape of trajectory (Schlapfer and Schmid, 1999);

a) Species are primarily redundant: Hypothetical trajectories having predominantly insensitive or flat to variation in biodiversity imply that loss of species is compensated for by other species or the addition of such species adds nothing new to the system.

b) Species are primarily singular: Hypothetical trajectories with slopes predominantly positive or negative imply that species contribute to ecosystem functioning, resulting in loss or addition causes detectable changes in functioning. Keystone species are unique examples of singular species.

c) Species impacts are context-dependent and therefore, idiosyncratic or unpredictable: Hypothetical trajectories that exhibits a variety of different slopes over different portions of their trajectory where impact of loss or addition of a species depends on conditions, for examples, community composition, site fertility, disturbance regime, under which the local extinction or addition occurs.

Three Demonstration Wetlands

Possible Species Lists
From JFNew, Inc. (http://www.jfnew.com/)

Wetland Type 1 High Diversity Wetland (No Cattail)
Permanent Grasses/Sedges Carex comosa Bristly Sedge Carex cristatella Crested Oval Sedge Carex lurida Bottlebrush Sedge Carex frankii Bristly Cattail Sedge Carex vulpinoidea Brown Fox Sedge Eleocharis palustris Great Spike Rush Elymus virginicus Virginia Wild Rye Glyceria striata Fowl Manna Grass Leersia oryzoides Rice Cut Grass Scirpus atrovirens Green Bulrush Scirpus cypernus Wool Grass Scirpus pungens Chairmaker's rush Scirpus validus Great Bulrush Sparganium eurycarpum Great Bur Reed	Forbs Acorus calamus Sweet Flag Alisma spp. Water Plantain (Various Mix) Asclepias incarnata Swamp Milkweed Aster puniceus Swamp Aster Bidens spp. Bidens (Various Mix) Decodon verticillatus Swamp Loosestrife Eupatorium perfoliatum Common Boneset Helenium autumnale Sneezeweed Hibiscus spp. Rosemallow (Various Mix) Iris virginica Blue Flag Iris Lobelia siphilitica Blue Lobelia Ludwigia alternifolia Seedbox Mimulus ringens Monkey Flower Peltandara virginica Arrow Arum Rudbeckia laciniata Wild Golden Glow Sagittaria latifolia Broad-Leaf Arrowhead Senna hebecarpa Wild Senna Thalictrum dasycarpum Purple Meadow Rue Verbena hastata Blue Vervain Verbesina alternifolia Wingstem Vernonia spp. Ironweed (Various Mix)
Wetland Type 2 High Diveristy Wetland (With Cattail) In addition to all species in the high diversity wetland, we include Typha latifolia, broadleaved cattail.	Wetland Type 3 Cattail Monoculture Monoculture of Typha latifolia, broadleaved cattail.

Further Background

Effects of Species Richness and Composition

The Effects of species richness and composition Diversity’s effect on ecosystem properties

Diversity might have no effect: changing relative abundance or species richness might not change process rates or pool sizes

Increases in ecosystem functioning with increasing diversity could arise from two primary mechanisms:

i) First, only one or a few species might have a large effect on any given ecosystem property. Increasing species richness increases the likelihood that those key species would be present.

ii) Second, species or functional richness could increase ecosystem properties through positive interactions among species.

A saturating response of ecosystem properties to increasing species richness is the most commonly hypothesized pattern

Complementarity and selection or sampling effects are not necessarily mutually exclusive.—There can be a continuum of diversity effects, ranging from the probability of sampling one dominant species to the probability of selecting several complementary species

Ecologists disagree over whether sampling effects are relevant to natural ecosystems· Adding multiple trophic levels is expected to lead to more complex responses in ecosystem properties than in single-trophic-level models

Experiments and observations Experiments and observation.—Much of the experimental work on the effects of plant diversity on ecosystem properties has focused on primary productivity and ecosystem nutrient retention, although a growing number of studies have considered decomposition and nutrient dynamics as well.o Differences in species composition exert a strong effect on productivity and other ecosystem propertieso Patterns of response to experimental manipulations of species richness vary for different processes, different ecosystems, and even different compartments within ecosystemso Both sampling effects and positive species interactions have been observed in experiments, and multiple mechanisms can operate simultaneously or sequentially.o The strength of positive interactions varies with both the functional characteristics of the species involved and the environmental context.o Higher species richness within sites tends to decrease invasion by exotic species, though cross-site comparisons often show positive correlations between richness and invasibility.o Varying diversity and composition of heterotrophs can lead to more idiosyncratic behavior than varying diversity of primary producers alone.
Variability in ecosystem properties Theory and hypotheses.—Ecologists hypothesize that ecosystem properties should be more stable in response to environmental fluctuations as diversity increases.o A diversity of species with different sensitivities to a suite of environmental conditions should lead to greater stability of ecosystem properties.o The numbers of species or genotypes necessary to maintain ecosystem properties increases with increasing spatial and temporal scaleso The underlying assumptions of the mathematical models need further investigation and more experimental confirmation
Experiments and observations o Experiments and observations.—While theory about effects of species and functional diversity on stability of ecosystem properties is relatively well developed, testing the predictions of this theory is more difficult. Such studies require long-term investigations of communities where differences in species diversity are not confounded by variation in other ecosystem properties, such as soil fertility or disturbance regime.o In diverse communities, redundancy of functional effect types and compensation among species can buffer process rates in response to changing conditions and species losses.o Mechanisms other than compensation can affect stability in response to changing species richness or composition.o Several experiments that manipulate diversity in the field and in microcosms generally support theoretical predictions that increasing species richness increases stability of ecosystem properties, although most experiments are confounded by other variableso Explicit demonstration of compensation among species requires careful experimental control and cannot be taken for granted as the mechanism underlying stability responses

Planting a New Wetland in Southwest Ohio

Hydrology and Geology

Plantings

Possible Plants Sites:

http://www.jfnew.com/files/seed-mixes/2008-emergent-seedmix.pdf
http://plants.usda.gov/java/characteristics?txtparm=&category=sciname&familycategory=all&duration=all&growthhabit=all&nativestatus=nPFA&wetland=
wetland&stateSelect=US39&sort=sciname&submit.x=47&submit.y=6
For Cuyahoga County (Delong, Jog, & Wilder, 2005)

Invasive species competition

Native plants must compete with non-native plants, such as Phalaris arundinacea L. (reed canary grass) (Adams & Galatowitsch, 2006)

Control of:

Spring burning, spring glyphosphate herbicide (Adams & Galatowitsch, 2006)

Lowering light availability with a cover crop (Perry & Galatowitsch, 2004)

Nitrogen availability (Perry, Galatowitsch, & Rosen, 2004)

Carex hystericina (native) out competes Phalaris arundinacea for nitrogen content in soil

Carbon enrichment of soil lowers inorganic nitrogen in soil

Suggests lowering nitrogen in soils through carbon enrichment, vegetation harvests, and reduced nitrogen inputs

Traits

Denitrification (Smialek, Bouchard, Lippmann, Quigley, Granata, Martin, & Brown, 2006)

Certain plants can be planted in constructed wetlands to favor denitrification, while buffering methane emission”

Juncus effusus limited methane emission

Long-term removal of nitrate

Salix nigra enhances release of methane

Methane cycle (Smialek, Bouchard, Lippmann, Quigley, Granata, Martin, & Brown, 2006)

Methane in sediment

Emmissions of methane from sediment and through plants

IBI (plant-based index of biological integrity), called VIBI

Assess ecological integrity of stream fish and macroinvertebrates most common taxa used as indicator species (Mack, 2007)

Applied to wetlands using vascular plants by State of Ohio in 1996, (Mack, 2007)

Emergent-, forest-, and shrub-dominant wetlands

Vegetation IBIs-emergent (VIBI-E), significantly correlated with the disturbance gradient (Mack, 2007)

Mycorrhizal and fungi (Bohrer, Friese, Amon, 2004)

Arbuscular mycorrhizal fungi (AMF) associations

Seasonal dynamics of arbuscular mycorrhizae in response to plant phenology

“Prevalent in spring during new root and vegetative growth”

Soil

Soil removal for hydrology and reduction of non-native plants (Hausman, Fraser, Kershner, & de Szalaye, 2007)

Altered biotic and abiotic environment, proximity to water table primary controlling factor of plant communities (Hausman, Fraser, Kershner, & de Szalaye, 2007)

Wetland plants adapted to high P-CO2 pressure in their roots are best adapted for soils with high P-CO2 levels in the soil (Greenway, Armstrong, & Colmer, 2006).

Heavy metals removal (a constructed wetlands?) (Lung & Light, 1996)

Phytoplankton biomass and productivity

Macrophyte biomass

Total phosphorus

Dissolved, particulate copper in water and sediments

Suspended solids

Phosphorus (D’Angelo, 2005)

Late successional bottomland forest wetlands have 3x greater capacity to remove/retain inorganic phosphorus

“Mostly due to higher amounts of amorphous aluminum oxides, organically-bound aluminum, and organic carbon in these soils”

Denitrification (Hernandez & Mitsch, 2007)

Significantly correlated with soil temperature and growing season nitrate concentrations

Important factors: flood frequency, nitrate availability, and soil temperature

"Experimental Design" -- Selection of species with regard to composition and diversity

Assessing Performance of Ecosystem Processes

Bibliography

Adams, C.R., and S.M. Galatowitsch. 2006. Increasing the effectiveness of reed canary grass (Phalaris arundinacea L.) control in wet meadow restorations. Restoration Ecology 14(3): 441-451.

D’Angelo, E.M. 2005. Phosphorous sorption capacity and exchange from mitigated and late successional bottomland forest wetlands. Wetlands 25(2): 297-305.

Delong, M.K., S.K. Jog, J.R. Johansen, and G.J. Wilder. 2005. Floristic survey of a highly disturbed wetland within Shaker Median Park, Beachwood (Cuyahoga County), Ohio. Ohio Journal of Science 105(5): 102-115.

Greenway, H., W. Armstrong, and T.D. Colmer. 2006. Conditions leading to high CO2 (> 5 kPa) in waterlogged-flooded soils and possible effects on root growth and metabolism. Annals of Botany 98(1): 9-32.

Hausman, C.E., L. H. Fraser, M.W. Kershner, and F.A. de Szalaye. 2007. Plant community establishment in a restored wetland: effects of soil removal. Applied Vegetation Science 10(3): 383-U81.

Hernandez, M.E., and W.J. Mitsch. 2007. Denitrification in created riverine wetlands: influence of hydrology and season. Ecological Engineering 30(1): 78-88.

Hooper, D. U.; Chapin, F. S.; Ewel, J. J.; Hector, A.; Inchausti, P.; Lavorel, S.; Lawton, J. H.; Lodge, D. M.; Loreau, M.; Naeem, S.; Schmid, B.; Setala, H.; Symstad, A. J.; Vandermeer, J.; and Wardle, D. A. 2005. Effects of biodiversity on ecosystem functioning: A consensus of current knowledge. Ecological Monographs 75: 3-35.

Lung, W.S., and R.N. Light. 1996. Modelling copper removal in wetland ecosystems. Ecological Modelling 93(1-3): 89-100.

Mack, J.J. 2007. Developing a wetland IBI with statewide application after multiple testing iterations. Ecological Indicators 7(4): 864-881.

Naeem, S.; Thompson, L.J.; Lawler, S.P.; Lawton, J.H.; Woodfin, R.M. 1994a. Declining biodiversity can alter the performance of ecosystems. Nature 368, 734–737.

Perry, L.G., and S.M. Galatowitsch. 2004. The influence of light availability on competition between Phalaris arundinacea and a native wetland sedge. Plant Ecology 170(1): 73-81.

Perry, L.G., S.M. Galatowitsch, and C.J. Rosen. 2004. Competitive control of invasive vegetation: a native wetland sedge suppresses Phalaris arundinacea in carbon-enriched soil. Journal of Applied Ecology 41(1): 151-162.

Schlapfer, F. and Schmid, B. 1999. Ecosystem effects of biodiversity: a classification of hypotheses and exploration of empirical results. Ecological Applications 9: 893-912.

Smialek, J., V. Bouchard, B. Lippmann, M. Quigley, T. Granata, J. Martin, and L. Brown. 2006. Effect of a woody (Salix negra)and an herbaceous (Juncus effusus) macrophyte species on methane dynamics and denitrification. Wetlands 26(2): 509-517.

Zedler, J. B. 2003. Wetlands at your service: reducing impacts of agriculture at the watershed scale. Frontiers in Ecology and the Environment 1:65-72. etc.