CAS/GRS 417/617

Lakes and Rivers

Semester II

Instructor: Stjepko Golubic, e-mail: golubic@bu.edu;  Tel. 3-2436,

Prerequisites:  CAS BI 107, 108 or 118, and PY 105, 106, and CH 101, 102.

Lakes and riveers have been the subject of ecological research for more that a century, contributing significantly to insights and understanding of basic ecological principles.  The study of lakes and rivers requires interdisciplinary approach in order to understand the mutual affect and regulatory mechanisms between the biota and their environment.  These interdependencies exist in the entire biosphere, but are best illustrated in aquatic ecosystems.  The course offers the students an opportunity to broaden their education to evaluate geographic, geological, physical and chemical as well as biological properties of lakes and rivers and to familiarize themselves with the diversity of organisms in aquatic environments.  Preservation of natural waters and wetlands is essential for the prosperity of human population and the understanding of ecological interactions is essential for successful protection and management of water resources.  The course treats aquatic systems as a part of a wider landscape and its history, introduces basic principles of Limnophysics, Limnochemistry and Limnobiology, and discusses the impact of various processes in natural waters on global cycling of elements.  Students engage in independent research and give presentations in style and format of professional meetings.

Textbook:  Dodson, S.I. 2005. Introduction to Limnology, McGraw-Hill Publishing Co. Recommended: Wetzel, R.G. 2001.  Limnology, Lake and River Ecosystems, 3^rd edition.  Academic Press (Elsevier Science, USA) 1006 pp.

Part I – Aquatic environment

  1  Introduction.  What is Limnology? – Human impact on freshwater ecosstems – Scientific approaches – Limnological  perspective: The need for an interdisciplinary approach. – ch. 1 (wch. 1)

  2  Water as substance, medium and environment.  Molecular properties – Isotopes – Specific heat – Density – Surface tension. – Water as a solvent – ch. 2

  3  Lotic and lentic systems  – The water flow.  – Lotic ecosystems – Groundwater and surface flow.  – Evaporation and precipitation – Runoff and groundwater. – ch. 3, 4

  4  Light penetration in water – Solar spectrum – Light absorption and transmission  – Color and turbidity of natural waters. – Thermal radiation. – ch. 5

  5  Heat distribution in water. – Thermal stratification and stability. – Stratification and lake classification. – Meromixis. – (ch. 6) –

  6  Water movement –  Turbulent and laminar flow. – Current velocity. – Effect of water flow on sediments. – External and internal waves and seiches – ch. 7.

Hydrological cycle and water economy – Erosion and sedimentation

  7  Structure & productivity.  The drainage basin concept. – Streams and rivers. – Detritus. – The river continuum concept. – The lake ecosystem concept. – Population growth and interrelationships. –  Primary and secondary productivity. – ch. 8

  8  Salinity of inland waters.   Ionic strength and composition.  – Sources of salinity. – Distribution of major cations: Ca, Mg, Na, K.  – Major anions: chloride, sulfate. – Salinity and osmoregulation.  Biota along the salinity gradient. – ch. 10

  9  Oxygen.  Atmosphere-Hydrosphere gas exchange – Oxygen solubility – Oxygen production by photosynthesis – Oxygen method in productivity assessments -  Oxygen consumption and loss – Vertical distribution of Oxygen and lake typology – Oxygen isotopes – Redox potential and mineral solubility. – ch. 9

10 Carbon.  Inorganic carbon cycle. – Alkalinity and acidity . – Inorganic carbon and pH in rivers and lakes. – CO₂ as carbon source in biosynthesis. – Heterotrophic CO₂ release and hypolimnetic accumulation. – ch. 11

11  Nitrogen.  Sources and transformation of Nitrogen.  – Denitrification and anamox. – Dinitrogen fixation – Nitrification – Dissolved and particulate N. – Distribution of N. – C:N ratios. – N-budgets. – ch. 12

12  Phosphorus.  Distribution of P in natural waters. – P in sediments. – Biological management of P budget. – P as required nutrient. – Humans and P-cycle. – Nutrient loading – and biota response. – ch. 13

13  Sulfur.  Sources of S. – Distrtibution of S in natural waters.  – Microbial Sulfur cycling. – ch. 14

14  Fe, Si and trace elements.  Redox potential and mineral solubility.  – Fe and Mn complexing. – Distr tibution of Fe and Mn in lakes. –  Microbial cycling of Fe and Mn.

15  Summary and discussion

EXAM – (Professional vocabulary, Bibliographic reviews)

Part II -  Aquatic communities

16  Phytoplankton and Primary producers.  Size classification of plankton. – Phytoplankton communities, nutritional requirements and lake classification. – Growth characteristics of plankton. – Pathogens and mortality of phytoplankton. – Grazing pressure. – Diversity of phytoplankton. – ch. 15

17  Cyanobacteria and oxygenic phototrophy.  The origins of phototrophy. –Anoxygenic phototrophs. – Antiquity of cyanobacteria. – Diversity of cyanobacteria. – ch. 15+

18  Cyanobacteria in pristine and disturbed ecosystems.  – Cyanobacteria in aquatic systems: Toxic cyanobacteria. – Plankton blooms of cyanobacteria, causes and consequences.  – Cyanobacteria in benthos, littoral, lotic systems. – ch. 15+

19  The origins of eukaryotic Phototrophy.   Lateral transfer of genetic information and endosymbiosis.  Phylogenetic relationships among aquatic phototrophs. – ch. 15+

20  Chrysophyta, Diatoms, Xanthophyta & Dinoflagellates.  Distribution and significance. – Plankton vs. benthos. – ch. 15+

21  Chlorophyta and aquatic plants.  Phylogenetic background and diversity. – Distribution.  – The role of macrophytes in aquatic systems. – ch. 18, 19, 20.

22  Macrophytes and periphyton.  Distribution: Land-water interfaces.  Periphyton and epipelon – Production rates. – ch. 19, 20

23  Zooplankton diversity. General characteristics of and diversity of protista, rotifera, cladocera & copepoda. – Vertical and horizontal distribution. – Time distribution. – Population dynamics. – Zooplankton and food chain. – ch.16

24  Benthic animals-1.  Protista, Porifera, Cnidaria, Turbellaria, Gastrotricha, Nematoda and Nematomorpha, Bryozoa, Oligochaeta, Hirudinea. – ch. 22

25  Benthic animals-2.  Tardigrada, Acarina, Ostracoda, Malacostraca, Mollusca, Insecta. – ch. 22

26  Fish communities.  Feeding relationships among fish. – Predation and biomanipulation. – Fish production. – ch. 16-18, 22-7

27  Bacterioplankton.  Organic carbon cycle and bacterioplankton. – DOC vs. POC. – Distribution. – Bacterivory. – ch. 17

28  Sediments and microflora.  Inorganic and organic sediment composition. – Distribution of bacteria. – Sediment-Water interface as bacterial habitat. – Functional (metabolic) guilds.  – Interactions. – ch. 21+ 

29  Summary and discussion  

      EXAM (Presentations)

Part III – Aquatic ecosystems and global context

30  Terrestrial inputs and outputs.  Distribution of dead organic matter. – The role of detritus in aquatic ecosystems. – Net ecosystem production. – ch. 23

31  Net ecosystem production and biotic stability.  Autochthonous and allochthonous organic carbon. – Distribution of C_org Decomposition of Organic matter. – microbial loop.  – ch. 23

32  Human inpacts.  Regulation of water ways. – Cross-contamination. – UV and the ozone layer. – CO₂-release. – Global warming. – Acidification. – Eutrophication. – Water pollution. – ch. 23+

33  Synergies and the organic carbon cycle.  _. – Synergies among DOC, Sunlight, increase CO₂ release, global warming, and acidification. – ch. 23-8

34  Paleolimnology: Sedimentary record. – Dating. – Inorganic geochemistry. – Organic geochemistry. – ch. 24+

35  Paleolimnology: Paleontological record.  Pollen and spore analysis. – Algal remains – Fossil plant material. – Animal remains – Chironomids – Cladocerans – Ostracods – Mollusks. – ch. 24

36  Ontogeny of inland water ecosystems.  Successional development of aquatic ecosystems. – Eutrophication.  – Oligotrophic conditions in calcareous waters. – Food change shortening. – Distrophy and bog ecosystems – Silting, paludification, terrestrialization. – ch. 25

37  Water quality and future.  Biodiversity. – Use and misuse of inland waters – Water supply and protection – River regulation. – Dams and Water reservoires – Climate change.  – Introduction of extraneous speciesl – Water pollution:  sources, consequences and assessment. – ch. 26+

38  Water treatment – Waste water treatments. – Lake management and restauration. – ch. 26+

39  Summary and discussion

     EXAM  (projects and presentations)