Content
Topic Introduction
In this topic we will look at a case study of an extreme tropical environment. In the tropics, the coastal zone between the high-water mark and low-water mark is often occupied by a specialized group of plants called mangroves. As a result, these areas are referred to as mangrove forests. The plants must be able to survive extreme conditions. They persist in a saline environment that would kill most plants. The substrate is loose and permanently water-logged. On top of that, the forests are flooded at high tide, so for much of the time, the roots and lower parts of the trunks are underwater. To survive these extreme conditions, mangrove plants have developed a number of remarkable adaptations, and we will examine these in this topic.
By the end of this topic, you should be able to:
- Assess how mangrove species survive in a tidal, salt-water environment.
- Compare the adaptations of mangrove plants with forest plants typical of dry land.
- Contrast the various adaptation strategies of mangroves.
Topic Readings
Required Readings
- Ghazoul, J. and Sheil, D. 2010. Tropical Rain Forest Ecology, Diversity, and Conservation. Oxford, Oxford University press, 516 pp. Section 9.3.
Optional Readings
- De Alvarenga, A.M.S.B., Botosso, P.C., Soffiatti, P. 2017. Stem growth and phenology of three subtropical mangrove tree species. Brazilian Journal of Botany 40 (4), 907-914. DOI: 10.1007/s40415-017-0397-9.
- Duke, N., 2006. Australia’s Mangroves. The authoritative guide to Australia’s mangrove plants. University of Queensland, Brisbane. 200 pp.
- Feller, I.C., Friess, D.A., Krauss, K.W., Lewis, R.R., III. 2017. The state of the world's mangroves in the 21st century under climate change. Hydrobiologia 803 (1), 1-12. DOI: 10.1007/s10750-017-3331-z.
- Feller, I.C., Friess, D.A., Krauss, K.W., Lewis, R.R., III. 2017. The state of the world's mangroves in the 21st century under climate change. Hydrobiologia 803 (1), 1-12. DOI: 10.1007/s10750-017-3331-z.
- Feller, I.C., Lovelock, C.E., Berger, U., McKee, K.L., Joye, S.B., Ball, M.C. 2010. Biocomplexity in mangrove ecosystems. Annual Reviews in Marine Science 2, 395-417.
- Giri, C., Long, J., Abbas, S., Murali, R.M., Qamer, F.M., Pengra, B. and Thau, D. 2015. Distribution and dynamics of mangrove forests of South Asia. Journal of Environmental Management 148, 101-111. DOI: 10.1016/j.jenvman.2014.01.020
- Giri, C., Ochieng, E., Tieszen, L.L. et al. 2011. Status and distribution of mangrove forests of the world using earth observation satellite data. Global Ecology and Biogeography 20 (1), 154-159.
- Kricher, J. 2011. Tropical Ecology. Princeton, New Jersey, USA: Princeton University Press. pp. 463-468.
- Leong, R.C., Friess, D.A., Crase, B., Lee, W.K., Webb, E.L. 2018. High-resolution pattern of mangrove species distribution is controlled by surface elevation. Estuarine Coastal and Shelf Science 202, 185-192. DOI: 10.1016/j.ecss.2017.12.015.
- Leong, R.C., Friess, D.A., Crase, B., Lee, W.K., Webb, E.L. 2018. High-resolution pattern of mangrove species distribution is controlled by surface elevation. Estuarine Coastal and Shelf Science 202, 185-192. DOI: 10.1016/j.ecss.2017.12.015.
- Kodikara, K,A,S., Jayatissa, L.P., Huxham, M., Dahdouh-Guebas, F., Koedam, N. 2018. The effects of salinity on growth and survival of mangrove seedlings changes with age. Acta Botanica Brasilica 32 (1), 37-46. DOI: 10.1590/0102-33062017abb0100.
- Naidoo, G. 2016. The mangroves of South Africa: An ecophysiological review. South African Journal of Botany 107, 101-113. DOI: 10.1016/j.sajb.2016.04.014.
- Pastor-Guzman, J., Dash, J., Atkinson, P.M. 2018. Remote sensing of mangrove forest phenology and its environmental drivers. Remote Sensing of Environment 205, 71-84. DOI: 10.1016/j.rse.2017.11.009.
- Reef, R., Feller, I.C., Lovelock, C.E. 2010. Nutrition of mangroves. Tree Physiology 30 (9), 1148-1160.
- Reis, C.R.G., Nardoto, G.B., Oliveira, R.S. 2017. Global overview on nitrogen dynamics in mangroves and consequences of increasing nitrogen availability for these systems. Plant and Soil 410 (1-2), 1-19. DOI: 10.1007/s11104-016-3123-7.
- Wang, W., Yan, Z., You, S. et al. 2011. Mangroves: obligate or facultative halophytes? A review. Trees – Structure and Function 25, 953-963.
Self-check Quiz
After viewing topic presentations, take this self-check quiz to check your own progress. This quiz is designed to see how well you remember some of the more important issues presented in the module. There are five questions, and each has a potential of 4 answers, only one of which is correct. When you are ready, click the link Self-check Quiz 2.3 to start taking the quiz.
Pre-readings and Discussion (For certification)
After reading Section 7.1.8 of Ghazoul, J. and Sheil, D. (2010) Tropical rain Forest Ecology, Diversity, and Conservation, choose to post one thought provoking question related to mangroves, and remember to answer/respond to at least one other student’s question on the discussion board Online Discussion Module 2 .
Graded Assignment (For certification)
- There is no graded assignment associated with this topic.
Topic Summary
We have looked at an extreme environment, namely mangroves. Mangroves grow in salt- and brackish water, and experience daily tidal cycles. They are largely (but not exclusively) related to the tropics. Only a few plants have managed to adapt to these conditions, and some of these are widespread. Others are much more restricted in their distributions.
Topic Self-review (For self learning)
To review what you have learned in the topic, you are encouraged to use the following reflection questions as a study guide to do a self-review for the topic:
- What are mangroves?
- Where are mangroves found?
- Why are there so few species of mangroves in comparison to most tropical rainforests?
- How to mangroves survive being flooded with saltwater every day?
- What reproductive strategies have mangroves evolved to cope with their environment?
|
|