Plant diversity and conservation value of wetlands along a rural–urban gradient
DOI:
https://doi.org/10.38201/btha.abc.v51.i1.4Keywords:
wetlands, rural–urban gradient, plant diversity, conservation value, floristic qualityAbstract
Background: Wetlands are the most threatened ecosystem in South Africa despite the range of ecosystem goods and services they provide. A significant cause of wetland destruction and degradation is a lack of understanding, by planners, policymakers and developers, of their ecological and socio-economic importance.
Objectives: This study assessed the floristic composition and diversity of wetlands in the former Tlokwe Municipal area along a rural–urban gradient.
Methods: Fourteen wetland sites were surveyed along an urbanisation gradient. Vegetation surveys were done in quadrats along transects in each wetland recording the cover-abundance of each species. The data were analysed by using ordinations, similarity percentages, and the adjusted Floristic Quality Assessment Index.
Results: Overall, the proportional species composition of urban and rural wetlands was mainly similar. Trends indicated that the alpha diversity increased with both habitat size and heterogeneity along a rural–urban gradient. In all wetlands, indigenous species were the most abundant, with the highest score in the largest urban wetland. The floristic quality varied widely along the gradient with none of the sites in pristine condition.
Conclusion: The similarity in species composition and floristic quality of the wetlands, as well as the high levels of indigenous species richness, indicated that urban wetlands are worthy of conservation. However, the signs of disturbances and the presence of alien species means that restoration strategies need to be implemented to improve the quality of the wetlands.
Downloads
References
Albert, D. & Minc, L., 2004, ‘Plants as regional indicators of Great Lakes coastal wetland health’, Aquatic Ecosystem Health & Management, 7(2), 233–247. https://doi.org/10.1080/14634980490461588
Baldwin, A., 2011, ‘Plant communities of urban wetlands: patterns and controlling processes’, in J. Niemelä (Ed.) Urban Ecology: Patterns, Processes, and Applications. New York: Oxford University Press, pp. 77–84. DOI:10.1093/acprof:oso/9780199563562.003.0010
Barnard, S., Venter, A., & Van Ginkel, C., 2013, ‘Overview of the influences of mining-related pollution on the water quality of the Mooi River system’s reservoirs, using basic statistical analyses and self organised mapping’, Water SA, 39(5), 655–662. DOI: 10.4314/wsa.v39i5.10
Bateganya, N.L., Nakalanzi, D., Babu, M., & Hein, T., 2015, ‘Buffering municipal wastewater pollution using urban wetlands in sub-Saharan Africa: a case of Masaka municipality, Uganda’, Environmental Technology, 36(17), 2149–2160. https://doi.org/10.1080/09593330.2015.1023363
Bengu, T.S., du Plessis, J., Modley, L.S., & van Dyk, J.C., 2017, ‘Health effects in fish from the polluted Orlando Dam and Klipspruit wetland system, Soweto, South Africa’, African Journal of Aquatic Science, 42(2), 131–141. https://doi.org/10.2989/16085914.2017.1347083
Beyer, H.L., 2007, Hawth’s Analysis Tools Version 3.27, Retrieved from http://www.spatialecology.com/htools/download.php
Calder, J.-L., Cumming, G.S., Maciejewski, K., & Oschadleus, H.D., 2015, ‘Urban land use does not limit weaver bird movements between wetlands in Cape Town, South Africa’, Biological Conservation, 187, 230–239. https://doi.org/10.1016/j.biocon.2015.04.021
Carter, V., Garrett, M.K., & Gammon, P.T., 1988, ‘Wetland Boundary Determination In The Great Dismal Swamp Using Weighted Averages 1’, JAWRA Journal of the American Water Resources Association, 24(2), 297–306. https://doi.org/10.1111/j.1752-1688.1988.tb02987.x
Cilliers, S., Cilliers, J., Lubbe, R., & Siebert, S., 2013, ‘Ecosystem services of urban green spaces in African countries – perspectives and challenges’, Urban Ecosystems, 16(4), 681–702, https://doi.org/10.1007/s11252-012-0254-3
Cilliers, S.S., Schoeman, L.L., & Bredenkamp, G.J., 1998, ‘Wetland plant communities in the Potchefstroom Municipal area, North-West, South Africa’, Bothalia, 28(2), 213–229, https://doi.org/10.4102/abc.v28i2.642
Cimon-Morin, J., & Poulin, M., 2018, ‘Setting conservation priorities in cities: approaches, targets and planning units adapted to wetland biodiversity and ecosystem services’, Landscape Ecology, 33(11), 1975-1995. https://doi.org/10.1007/s10980-018-0707-z
Clarke, K.R., & Gorley, R.N., 2006, ‘PRIMER v6: User Manual/Tutorial’, Plymouth: PRIMER-E Ltd.
Cowden, C., Kotze, D.C., Ellery, W.N., & Sieben, E.J.J., 2014, ‘Assessment of the long-term response to rehabilitation of two wetlands in KwaZulu-Natal, South Africa’, African Journal of Aquatic Science, 39(3), 237–247, https://doi.org/10.2989/16085914.2014.954518
Dallimer, M., Rouquette, J.R., Skinner, A.M.J., Armsworth, P.R., Maltby, L.M., Warren, P.H., & Gaston, K.J., 2012, ‘Contrasting patterns in species richness of birds, butterflies and plants along riparian corridors in an urban landscape’, Diversity and Distributions, 18(8), 742–753. https://doi.org/10.1111/j.1472-642.2012.00891.x
Ding, Y., Qian, S., Wu, X., Zhao, L., Lin, D., Zhang, J., & Yang, Y., 2019, Homogenization of China’s urban aquatic macrophyte communities: A meta-analytic study’, Ecological Indicators, 106, https://doi.org/10.1016/j.ecolind.2019.105506
Doherty, J.M., & Zedler, J.B., 2014, ‘Dominant graminoids support restoration of productivity but not diversity in urban wetlands’, Ecological Engineering, 65, 101–111. https://doi.org/10.1016/j.ecoleng.2013.07.056
Dolan, R.W., Moore, M.E., & Stephens, J.D., 2011, ‘Documenting effects of urbanization on flora using herbarium records’, Journal of Ecology, 99(4), 1055–1062. https://doi.org/10.1111/j.1365-2745.2011.01820.x
Ehrenfeld, J.G., 2000, ‘Evaluating wetlands within an urban context’, Urban Ecosystems, 4(1), 69–85. https://doi.org/10.1023/A:1009543920370
ESRI, 2010, ArcGIS, version 10.0. Redlands, CA: Environmental Systems Research Institude. Retrieved from http://www.esri.com
Everard, M., 1997, ‘Development of a British wetland strategy’, Aquatic Conservation: Marine and Freshwater Ecosystems, 7(3), 223–238. https://doi.org/10.1002/(SICI)1099-0755(199709)7:3<223::AID-AQC239>3.0.CO;2-O
Govender-Ragubeer, Y., Meeuwis, J., & McKay, T.M., 2014, ‘A series of unfortunate events: how the battle to save an urban wetland was both won and lost’, TD: The Journal for Transdisciplinary Research in Southern Africa, 10(1), 149–168. https://hdl.handle.net/10520/EJC154541
Hettiarachchi, M., Morrison, T.H., & McAlpine, C., 2015, ‘Forty-three years of Ramsar and urban wetlands’, Global Environmental Change, 32, 57–66. https://doi.org/10.1016/j. gloenvcha.2015.02.009
Hoeksema, R.J., 2007, ‘Three stages in the history of land reclamation in the Netherlands’, Irrigation and Drainage, 56(S1), S113–S126. https://doi.org/10.1002/ird.340
JB Marks Local Municipality, 2018, ‘2017–2018 Annual Report’. Retrieved from: http://www.jbmarks.co.za/sites/default/files/2019-06%20documents/2017-2018%20Annual%20Report.pdf
Jia, H., Ma, H., & Wei, M., 2011, ‘Urban wetland planning: A case study in the Beijing central region’, Ecological Complexity, 8(2), 213–221. https://doi.org/10.1016/j.ecocom.2011.03.002
Kallimanis, A.S., Mazaris, A.D., Tzanopoulos, J., Halley, J.M., Pantis, J.D., & Sgardelis, S.P., 2008, ‘How does habitat diversity affect the species–area relationship’, Global Ecology and Biogeography, 17, 532–538. https://doi.org/10.1111/j.1466-8238.2008.00393.x
Koekemoer, L., Janse van Vuuren, S., & Levanets, A., 2021, ‘The influence of land use impacted tributaries on water quality and phytoplankton in the Mooi River, North West Province, South Africa’, Bothalia, 51(1): 23–44 (hardcopy); 1–22 (online) [this issue].
Kruger, D.J.D., Hamer, A.J., & Du Preez, L.H., 2015, ‘Urbanization affects frog communities at multiple scales in a rapidly developing African city’, Urban Ecosystems, 18(4), 1333–1352. https://doi.org/10.1007/s11252-015-0443-y
Lannas, K.S., & Turpie, J.K., 2009, ‘Valuing the provisioning services of wetlands: contrasting a rural wetland in Lesotho with a peri-urban wetland in South Africa’, Ecology and Society, 14(2), 18. http://www.ecologyandsociety.org/vol14/iss2/art18/
Louw, W.J., 1951, ‘An ecological account of the vegetation of the Potchefstroom area’, Memoirs of the Botanical Survey of South Africa, No. 24.
Manuel, P.M., 2003, ‘Cultural perceptions of small urban wetlands: cases from the Halifax Regional Municipality, Nova Scotia, Canada’, Wetlands, 23(4), 921–940. https://doi.org/10.1672/0277-5212(2003)023[0921:CPOSUW]2.0.CO;2
McGarigal, K., & Marks, B.J., 1995, ‘FRAGSTATS: spatial pattern analysis program for quantifying landscape structure. Gen. Tech. Rep. PNW-GTR-351’, Pacific Northwest Research Station, Portland: U.S. Department of Agriculture, Forest Service.
McInnes, R.J., & Everard, M., 2017, ‘Rapid Assessment of Wetland Ecosystem Services (RAWES): An example from Colombo, Sri Lanka’, Ecosystem Services, 25, 89–105. https://doi.org/10.1016/j.ecoser.2017.03.024
Miller, S.J., & Wardrop, D.H., 2006, ‘Adapting the floristic quality assessment index to indicate anthropogenic disturbance in central Pennsylvania wetlands’, Ecological Indicators, 6(2), 313–326. https://doi.org/10.1016/j.ecolind.2005.03.012
Mucina, L., Hoare, D.B., Lötter, M.C., du Preez, P.J., Rutherford, M.C., Scott-Shaw, C.R., Bredenkamp, G.J., Powrie, L.W., Scott, L., Camp, K.G.T., Cilliers, S.S., Bezuidenhout, H., Mostert, T.H., Siebert, S.J., Winter, P.J.D., Burrows, J.E., Dobson, L., Ward, R.A., Stalmans, M., Oliver, E.G.H., Siebert, F., Schmidt, E., Kobisi, K., & Kose, L., 2006, ‘Grassland Biome’ in L. Mucina & M.C. Rutherford (Eds.) The Vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. Pretoria: South African National Biodiversity Institute, pp. 349–436.
Panuccio, M., Foschi, F., Audinet, J.-P., Calò, C.M., & Bologna, M.A., 2017, ‘Urban wetlands: wastelands or hotspots for conservation? Two case studies from Rome, Italy’, Avocetta, 41, 13–18 https://doi.org/10.30456/AVO.2018103
Parker, K.A., Springall, B.T., Garshong, R.A., Malachi, A.N., Dorn, L.E., Costa-Terryll, A., Mathis, R.A., Lewis, A.N., MacCheyne, C.L., Davis, T.T., Rice, A.D., Varh, N.Y., Li, H., Schug, M.D., & Kalcounis-Rueppell, M.C., 2018, ‘Rapid Increases in Bat Activity and Diversity after Wetland Construction in an Urban Ecosystem’, Wetlands, 39(4), 717–727. https://doi.org/10.1007/s13157-018-1115-5
Pedersen, E., Weisner, S.E.B., & Johansson, M., 2019, ‘Wetland areas’ direct contributions to residents’ well-being entitle them to high cultural ecosystem values’, Science of the Total Environment, 646, 1315–1326. https://doi.org/10.1016/j.scitotenv.2018.07.236
Perron, M.A.C., & Pick, F.R., 2020, ‘Stormwater ponds as habitat for Odonata in urban areas: the importance of obligate wetland plant species’, Biodiversity and Conservation, 29(3), 913–931. https://doi.org/10.1007/s10531-019-01917-2
Pretorius, C., Du Toit, M., & Cilliers, S., 2013, ‘Effect of land-cover change on the vegetation types and ecosystem services of the Tlokwe Municipal Area, North West Province’, South African Journal of Botany(86), 165–166. https://doi.org/10.1016/j.sajb.2013.02.103
Purseglove, J.J., 1989, ‘Taming the Flood: a history and natural history of rivers and wetlands’, Oxford: Oxford University Press.
Ramírez, F., & Santana, J.C., 2019, ‘Key lessons learned by teaching ecotourism to undergraduate students in Bogotá’s urban wetlands’, Applied Environmental Education & Communication, 18(3), 234–251. https://doi.org/10.1080/1533015X.2018.1454359
Ramsar Convention Secretariat, 2013, ‘The Ramsar Convention Manual: a guide to the Convention on Wetlands (Ramsar, Iran, 1971)’, (6th ed.), retrieved from https://www.ramsar.org/sites/default/files/documents/library/manual6-2013-e.pdf
Retief, E., & Herman, P.P.J., 1997, Plants of the northern provinces of South Africa: keys and diagnostic characters, Strelitzia 6, National Biodiversity Institute, Pretoria.
Roberts, D., 1993, ‘The vegetation ecology of municipal Durban, Natal: floristic classification’, Bothalia, 23(2), 271–326. https://doi.org/10.4102/abc.v23i2.813
Ruto, W., Kinyamario, J., Ng’etich, N., Akunda, E., & Mworia, J., 2012, ‘Plant species diversity and composition of two wetlands in the Nairobi National Park, Kenya’, Journal of Wetlands Ecology, 6, 7–15. https://doi.org/10.3126/jowe.v6i0.5909
Semlitsch, R.D., & Bodie, J.R., 1998, ‘Are small, isolated wetlands expendable?’, Conservation Biology, 12(5), 1129–1133. https://doi.org/10.1046/j.1523-1739.1998.98166.x
Sieben, E.J.J., Collins, N.B., Corry, F.T.J., Kotze, D.C., Job, N., Muasya, A.M., Venter, C.E., Mtshali, H., Zondo, S.A., Janks, M., & Pretorius, L., 2016, ‘The vegetation of grass lawn wetlands of floodplains and pans in semi-arid regions of South Africa: Description, classification and explanatory environmental factors’, South African Journal of Botany, 104, 215–224. https://doi.org/10.1016/j.sajb.2015.11.003
Sieben, E.J.J., Collins, N.B., Kotze, D.C., Mofutsanyana, S.S., & Janks, M., 2017, ‘Temperate grassy wetlands of South Africa: Description, classification and explanatory environmental factors’, South African Journal of Botany, 113, 68–76. https://doi.org/10.1016/j.sajb.2017.07.009
Sieben, E.J.J., Mtshali, H., & Janks, M., 2014, ‘National Wetland Vegetation Database: Classification and analysis of wetland vegetation types for conservation planning and monitoring. WRC Report No. 1980/1/14’: W. R. Commission.
Skowno, A.L., Poole, C.J., Raimondo, D.C., Sink, K.J., Van Deventer, H., Van Niekerk, L., Harris, L.R., Smith-Adao, L.B., Tolley, K.A., Zengeya, T.A., Foden, W.B., Midgley, G.F., & Driver, A., 2019, ‘National Biodiversity Assessment 2018: The status of South Africa’s ecosystems and biodiversity. Synthesis Report’, South African National Biodiversity Institute & Department of Environment, Forestry and Fisheries, http://hdl.handle.net/20.500.12143/6362
Soomers, H., Karssenberg, D., Soons, M.B., Verweij, P.A., Verhoeven, J.T.A., & Wassen, M.J., 2013, ‘Wind and water dispersal of wetland plants across fragmented landscapes’, Ecosystems, 16(3), 434–451. https://doi.org/10.1007/s10021-012-9619-y
South Africa, 1998, ‘National Water Act 36 of 1998’, Pretoria: Government Printer
Tiner, R.W. ,1999, ‘Wetland Indicators: a guide to wetland identification, delineation, classification and mapping’, USA: Washington D.C.: Lewis Publishers.
Tiner, R.W., 2006, ‘Lists of potential hydrophytes for the united states: a regional review and their use in wetland identification’, Wetlands, 26(2), 624–634. https://doi.org/10.1672/0277-5212(2006)26[624:LOPHFT]2.0.CO;2
Van der Walt, L., Cilliers, S.S., Du Toit, M.J., & Kellner, K., 2014, ‘Conservation of fragmented grasslands as part of the urban green infrastructure: how important are species diversity, functional diversity and landscape functionality?’, Urban Ecosystems, 18, 87–113. https://doi.org/10.1007/s11252-014-0393-9
Van Deventer, H., van Niekerk, L., Adams, J., Dinala, M.K., Gangat, R., Lamberth, S.J., Lötter, M., Mbona, N., Mackay, F., Nel, J.L., Ramjukadh, C.-L., Skowno, A., & Weerts, S.P., 2020, ‘National Wetland Map 5: An improved spatial extent and representation of inland aquatic and estuarine ecosystems in South Africa’, Water SA, 46(1), 66–79, https://doi.org/10.17159/wsa/2020.v46.i1.7887
Van Ginkel, C., Glen, R., Gordon-Gray, K., Cilliers, C., Muasya, M., & Van Deventer, P., 2011, ‘Easy identification of some South African wetland plants (grasses, restios, sedges, rushes, bulrushes, eriocaulons and yellow-eyed grasses)’, Water Research Commission, Gezina,(WRC Report No. TT 479/10).
Wondie, A., 2018, ‘Ecological conditions and ecosystem services of wetlands in the Lake Tana Area, Ethiopia’, Ecohydrology & Hydrobiology, 18(2), 231–244, https://doi.org/10.1016/j.ecohyd.2018.02.002
Working for Wetlands, 2019, Introduction and background [online], available at: www.environment.gov.za/projectsprogrammes/workingfowetlands (Accessed: 1 October 2019)
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2021 Creative Commons Attribution 4.0 International license (CC BY 4.0)
This work is licensed under a Creative Commons Attribution 4.0 International License.
