1. Plants and the Littoral Zone Ecology and Diversity

2. Growth Habits and Locations of Plant Types in the Littoral Zone

3. Emergent Macrophytes Rooted in the substrate Leaves fully exposed to air Usually rhizomatous Stems and leaves usually with aerenchyma or lacunae Nutrient uptake from the sediment and inorganic carbon from the air

4. Examples of emergent macrophytes Typha: commonly called cattail, is very characteristic of wetland communities. Typha is a monocot related to grasses.

5. Examples of emergent macrophytes Glyceria: mannagrass, is an aquatic grass with leaves that are very rough to the touch

6. Examples of emergent macrophytes Phragmites: called common reed, is a grass that grows aggressively in aquatic and semi- aquatic environments

7. Examples of emergent macrophytes Zizania: wild rice, is related to the grass, Oryza, true rice

8. Examples of emergent macrophytes Eleocharis: spikerush (more appropriately spikesedge), is a grass-like plant in the sedge family. The genus is similar to a diminuitive Scirpus in that it makes spike- like stems without leaves.

9. Examples of emergent macrophytes Scirpus: commonly called bulrushes, are in the sedge family. They are rhizomatous with hollow stems. Leaves are associated with the inflorescence, which is subapical.

10. Examples of emergent macrophytes Carex: the dominant genus of sedges (>1500 species). These grass-like plants have stems that are triangular in x-section.

11. Examples of emergent macrophytes Juncus: rush, superficially resembles Eleocharis. However, it forms a tuft of spike-like stems that grow from a basal rosette of leaves.

12. Examples of emergent macrophytes Polygonum: smartweed or knotweed, is recognized by having swollen nodes and has many species, but only a few are aquatic. The native species is frequently found associated with the margins of lakes, ponds, reservoirs, and in backwater areas of rivers and creeks. Japanese Knotweed, an invasive from Asia, also is found associated with wet areas, but rarely in the water.

13. Examples of emergent macrophytes Equisetum: horsetail. The common one found in water is E. fluviatile, the river horsetail. These plants are related to ferns.

14. Floating-leaved rooted macrophytes Generally rhizomatous Floating leaves with cuticle on upper surface Petiole usually very long Nutrient uptake from the sediments and inorganic carbon often from both the water and air

15. Floating-leaved macrophytes, rooted Nuphar: spatterdock or cow lily, is rhizomatous with large floating leaves. All stems and roots are in the mud. The plant is common to aquatic systems throughout the northern hemisphere.

16. Floating-leaved macrophytes, rooted Nymphaea: waterlily is very similar to Nuphar but it has a large showy flower, which makes it a favorite of water gardens.

17. Floating-leaved macrophytes, rooted Brasenia: watershield is similar to Nuphar, but smaller. The stems, though technically rhizomatous, emerge from the substrate.

18. Floating-leaved macrophytes, rooted Nelumbo, lotus, resembles Nymphaea. However, some of its leaves are emergent. One species is native to North America.

19. Floating-leaved macrophytes, rooted Potamogeton: pondweed is rooted with elongate stems and floating leaves.

20. Unrooted floating-leaved macrophytes Many have gas-filled floats or tissue Some have leaves that are entirely aerial All have a hanging root system (or modified tissues that operate as roots), thus nutrient uptake entirely from water but inorganic carbon from the air Stems are highly reduced

21. Floating-leaved macrophytes, not rooted Lemna: duck weed, a common floating plant throughout the northern hemisphere.

22. Floating-leaved macrophytes, not rooted Wolffia, water meal, is the world’s smallest flowering plant. Often, it is found together with Lemna.

23. Floating-leaved macrophytes, not rooted Eichhornia, water hyacinth is a large free-floating plant from South America that has become a noxious weed of waterways in the southern US.

24. Floating-leaved macrophytes, not rooted Pistia, water lettuce, was first found in Egypt near the Nile. Now it has been dispersed by humans to nearly all tropical and subtropical waterways. It has become a pest in the US on some waterways.

25. Free-floating unrooted macrophytes Plants are almost entirely submerged, but may float at the surface In general, the leaves are highly-dissected Fragmentation a major form of reproduction and dispersal Roots rare; thus, nutrient uptake entirely from water

26. Free-floating macrophytes, not rooted Utricularia: bladderwort, is an aquatic carnivorous plant. There are more than 250 species and the genus has global distribution. Some species have become pests in some regions.

27. Free-floating macrophytes, not rooted Ceratophyllum, hornwort or coontail, is global in distribution and usually found in hard water ponds and lakes.

28. Submerged rooted aquatic plants In general, the leaves are highly dissected Nutrient uptake both from water and sediment

29. Submerged rooted macrophytes Myriophyllum, water milfoil, is native to Eurasia and has become a pest in many relatively still bodies of water.

30. Submerged rooted macrophytes Elodea: waterweed is submerged and native to North America. It can root in sluggish streams. They can be very abundant in nutrient-rich lakes and ponds. Used globally as an aquarium plant.

31. Submerged rooted macrophytes Vallisneria: water celery or tape grass, is a rooted plant with broad leaves that is frequently found in local creeks.

32. Submerged rooted macrophytes Isoetes, quillwort is a fern ally with corm-like bases to the leaves. An indicator of acid- sensitive water. Sometimes they are emergent.

33. Submerged rooted macrophytes Chara, muskgrass or skunkweed, is a non-vascular plant. Many of the species have a fetid odor. This genus usually is found in hard water ponds and lakes.

34. Submerged rooted macrophytes Nitella, stoneworts or brittleworts, are related to Chara but may occur in soft water ponds and lakes. They do not deposit calcium carbonate in their cell walls as many Chara species do, and therefore, are soft to the touch.

35. Zonation in Ozera Nero From the shore to the lake center – Salix – Phragmites – Typha – Scirpus – Equisetum – Potamogeton – Nuphar – Lemna (in all emergent plants) – Ceratophyllum

36. Sam Rayburn Reservoir Marginal macrophytes make tight concentric bands of: – Nitella – Potamogeton – Elodea

37. Main Stem of the Susquehanna River Beds of macrophytes in backwater areas and in the clear water of the West Branch – Vallisneria – Polygonum – Glyceria

38. Impacts of macrophyte dominance High primary production Decreased turbulence More efficient (than algae) nutrient uptake and sequestration?? Increased water clarity High organic load

39. Heterophylly Many aquatic plant species show differences in leaf shape when in or out of the water.

40. Reproduction, dispersal, and dormancy Asexual: e.g. Potamogeton – Winter buds – Agamospermy Vegetative: e.g. Myriophyllum Sexual: – Insect pollination e.g. Nuphar – Wind pollination e.g. Typha – Water pollination e.g. Potamogeton and Elodea

41. Movement of gases Diffusion-dependent throughflow convections. e.g. Fig 18-2

42. Movement of gases Nonthroughflow Venturi-induced throughflow Methane to atmosphere very high for emergent and floating-leaved rooted plants. Oxygen transport in submerged macrophytes Lacunae in roots and rhizomes may promote an oxidizing area around the roots which protects from H 2 S

43. Carbon uptake CO 2 diffusion much slower in water than air No cuticle in submerged leaves Chloroplasts in epidermis Many can decarboxylate bicarbonate Often high release of CO 2 from sediments in areas with macrophytes Can recirculate CO 2 within plant via lacunae

44. CAM Metabolism Found in certain aquatic plants and certain desert plants. Allows for CO 2 uptake at night when inorganic carbon highest in water.

45. CAM photosynthesis Keeley, J.E. 1985. The role of CAM in the carbon economy of the submerged-aquatic Isoetes howellii. Verh. Internat. Verein. Limnol. 22: 2909-2911.

48. Phosphate and nitrate enrichment relative to biomass

54. Plants and Water Velocity

55. Relationship between pH and alkalinity

56. RIVERSRESERVIORSLAKES Littoral zone/wetland Land-water interface well developed Land-water interface poorly developed Land-water interface well developed Macrophyte community structure With emergent, floating, and submerged macrophytes Wetland macrophytes in riverine portion, limited submerged plants, floating plants dominant Well-developed emergent, floating, and submerged macrophytes Nutrient acquisition Mainly through roots Most from sediments Light acquisition Limited by canopy in low order streams and by turbidity and algae in high order streams Limited to shallow areas due to turbidity Mostly unrestricted except for submerged macrophytes Macrophyte biomass and production High in floodplain; low in low order streams, highest in mid-order streams and low in high order streams Low to moderate, mainly in riverine wetlands; floating- leaved macrophytes can be very productive High to very high, mainly with emergent macrophytes