Introduction to SAV and Seagrass of Our Coastal Waters

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1 Introduction to SAV and Seagrass of Our Coastal Waters Hyun Jung (J.) Cho Department of Biology Jackson State University 1400 Lynch St. Jackson, Mississippi 39217

2 Submerged Aquatic Plants (SAV) Flowering vascular plants that grow (completely) beneath the surface of water and usually rooted in the sediment.

3 SAV: How do they live in water? Surrounded by Water: water loss not a problem unless it is saltwater Absence of or thin cuticle Stomata open most of time Terrestrial plant s cuticle

4 SAV: How do they live in water? Plant structures supported by water Less rigid structures because they are supported by water pressure Air sacs for flotation Flat leaves on water surface for flotation Smaller, feathery roots: no need to support the plant, but some can have extensive rhizomes 09/kf_ne_sav.aspx

5 SAV: How do they live in water? Dissolved nutrients & gases and light are limiting factors Specialized roots uptake oxygen. Increased number of stomata on either side of leaves cwrp.org

6 SAV: How do they live in water? nutrients and gas uptake from water columns as well as substrates Under normal conditions, the vascular plants can outcompete algae. With eutrophication, overgrowth of vegetation can cause noxious problems. cwrp.org

7 Then, what is a SEAGRASS? SAV which grows in marine, fully-saline environments A group of flowering plants which grow fully submerged and rooted in estuarine and marine environments Not a true grass, but all monocotyledons

8 From Moncreiff

9 Importance of SAV / Seagrass Valuable resource and indicator of aquatic habitat quality Provide nursery habitats and food sources Reduce wave energy Stabilize sediments Reduce turbidity Global Conservation Issue Worldwide decline of coastal SAV

10 Potential Seagrass Habitat in Mississippi Sound Year Responsible Party (pub. Year) Hectares 1969 Eleuterius, L.N. (1973) 5, Moncreiff et al. (1998) Moncreiff 1,149

11 Earlier Documentation of Mississippi Seagrass Year Responsible Party Species recorded 1956 Humm Thalassia, Syringodium, Halodule, Halophila, Ruppia Eleuterius Thalassia, Syringodium, Halodule, Halophila, Ruppia 1999 Moncreiff Mainly Halodule and Ruppia

12 Thalassia testudinum (Turtlegrass)

13 Syringodium filiforme (Manateegrass)

14 Halophila engelmannii (Stargrass)

15 Halodule wrightii (Shoalgrass)

16 Ruppia maritima (Wigeongrass)

17 Why did we lose seagrass beds? Overall decline in water quality and habitat quality Increased turbidity Extended periods of depressed salinity Effects of Mississippi River water diversion Physical disturbances Hurricanes, developments, coastal erosions Physical loss of habitat

18 Linear Model of Potential SAV Habitat in Lake Pontchartrain when the shoreline slope in radians and I Z is 10% of I 0. is Z max - Z min Z min = (MHW-MLW) / 2 = 0.3 m X (Shoreface Distance of Potential SAV habitat) Z max = Z col = ln (I o /I z ) / K d = 2.3 / K d X = ( * K d ) / (sin * K d ) (Cho and Poirrier 2005 Restoration Ecology ) Figure 1. A diagram indicating the negative feedbacks of SAV loss of in a wave-stressed shore Increased water fluctuation Increased turbidity Waves Shoreline erosion SAV loss Alteration of bottom profiles Increase wave energy (Cho and May 2006 National Wetland Newsletter )

19 Water Quality Physical Environment Seagrass Biology and Ecology Seed Bank

20 Long-term Assessment of Seagrass Habitat Grand Bay National Estuarine Research Reserve

21 Transect Survey Site Transec t Start Stop Halodul e

22 HurricaneKatrina Percent Transect Portion Covered by Seagrass (patch density adjusted) Oct 2005 Oct 2006 Oct 2007 Oct 2008 Oct 2009 Ruppia maritima Halodule wrightii

23 Wigeongrass (Ruppia maritima) a coastal seagrass euryhaline species grown in all salinity zones a pioneer species grows well in bare habitats grows rapidly matures quickly highly dependent on sexual reproduction produces abundant seeds

24 Germination

25 Growing slowly in cold water

26 : Immature flowers enclosed in a sheath

27 : Inflorescence exposed above water surface

28 : Released pollen floating on water surface

29 : Stamens lost, left pistils

30 : Floating pollen contacting with pistil at water surface

31 : Seeds (fruits) on stalks

32 Essential Fisheries Habitat Restoration using Ruppia? Habitat Restoration returning a degraded habitat to a healthy, selfsustaining condition that resembles its pre-disturbed state Seagrass beds can be restored by encouraging natural recolonization proactive methods transplanting of plants from healthy donor beds seedlings reared under laboratory conditions

33 Rationale Mississippi and Coastal Objectives SAV Most SAV habitat models are based on long-term water quality monitoring data. Resource managers have limited ability to do extensive/consistent water quality monitoring, hence, usage of those models is limited. To develop coastal SAV community/habitat model that does not require long-term data collection. A Habitat Suitability Index (HSI) for SAV will be developed via a decision-tree algorithm approach that utilizes landscape properties.

34 Estuaries

35 Salt Marshes

36 Ruppia maritima (Wigeongrass)

37 Halodule wrightii (Shoalgrass)

38 Tidal Oligohaline Marshes

39 Freshwater Marshes

40 Vallisneria americana (American Wildcelery)

41 Najas guadalupensis (a), Potamogeton pusillus (b), and Zannichellia palustris (c) a b c

42 Nuphar lutea (a), Nelumbo lutea (b), and Nymphaea odorata (c and d) a c c b c d

43 Myriophyllum spicatum (a), Myriophyllum pinnatum (b), Myriophyllum aquaticum (c), and Proserpinaca pectinata (d) a d b c

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48 Freshwater Swamps

49 Callitriche heterophylla (Water starwort) d b c

50 Eleocharis robbinsii. Eleocharis baldwinii. Schoenoplectus subterminalis a b c

51 Lemna minor (a), Spirodela polyrhiza (b), and Wolffiella floridana (c) a c c b

52 Figure 10. logos of partners