Water Quality in the Amboseli Ecosystem
Extract from Croze, H., Sayialel, S. and Sitonic, D. (2006). What’s on in the ecosystem: Amboseli as a Biosphere Reserve. A Compendium of Conservation and Management Activities in the Amboseli Ecosystem. . 28 pp + annexes. Nairobi: ATE/AERPUNESCO, p.9:
"..., a string of groundwater-fed swamps are on the one hand the life-blood of the ecosystem and on the other the centre of gravity of the major commercial enterprises: tourism in the Amboseli National Park (Sinet, Enkong’u Narok and Lonkinya swamps), the Kimana Wildlife Concession (Kimana swamp) and on Kuku Group Ranch (Lenkati and Esoitpus swamps); and irrigated agriculture around the edges of Namelok and Kimana swamps.
ILRI commissioned a water quality survey in five important sources of water and grazing: Namelok, Kimana and Lenkati swamp, plus two of the very few important perennial rivers in the ecosystem: the Nol Turesh and the Rombo.
In the case of the swamps, samples were taken at the source of the swamp strings, inside the swamps where high-intensity irrigated agriculture is currently underway and near the downstream outlet of the swamp drainage.
The conclusions make disturbing reading. Even though people use the waters for domestic purposes all along the reaches of the swamps and rivers studied, “…most of the chemical parameters, … [the total suspended solids]… and concentration of iron, nitrates and phosphates are beyond the World Health Organization and Kenya Bureau of Standards safe limits. This in combination with pesticides application renders the water unsafe for human consumption and raises concerns on human, livestock and wildlife health issues.” (Githaiga and Muchiru 2003, page 25; Githaiga et al 2004)
Githaiga, J. M. and Muchiru, A. N. (2003). Survey of Water Quality Changes with Land Use Type in the Loitokitok Area, Kajiado District, Kenya. 32. Nairobi: ILRI/UNEP/GEF/University of Nairobi.
Githaiga, John M., Robin Reid, Andrew N. Muchiru and Sandra van Dijk (2004) Survey of Water Quality Changes with Land Use Type in the Loitokitok Area, Kajiado District , Kenya. LUCID Working Paper 35. Nairobi: ILRI (UNEP/GEF, MSU, Univ. Nairobi)
posted by Harvey Croze @ 14:40
1 comments
1 Comments:
[Mike Lane, in an email to HC of 21-02-2004, had this to say of the Githaiga and Muchiru report...]
The Githaiga/Muchiru paper is fine so far as it goes - but it doesn't go far enough; is it a draft report, or final issue? Limited discussion of dissolved oxygen (DO), though they claim to have collected DO values - they only mention DO in the Namalok Swamp context. They might have considered describing iron concentrations on a redox diagram. A shame that the opportunity to analyse a fuller suite of parameters was not seized; they (quite rightly) recommend that pesticide contamination be assessed - why did they not include this as part of their programme (given that pesticides and metabolites can be analysed at UoN e.g. Dr Dan Olago's lab at the Department of Geology)?
Being who I am I would have recommended
1) a far more thorough literature survey (e.g. the fluorescein tracer study undertaken as part of the Nol Turesh investigations would have given them a good deal of information on hydraulic connectivity between water source); see also comments re. their S 1.1 below.
2) isotope analyses (2H and 18O); CFC analysis; noble gas analyses (determination of the elevation of recharge of groundwater, which would have answered
S. 1.1 para 3: they state that "water resources in the area are in one way or another associated with Mt. Kilimanjaro" citing Touber et al's 1983 Soil Survey Report (citation incomplete, lead author's name spelled incorrectly). This is no longer an accepted truth in respect of the Chyulu Hills, which are strictly local in origin (i.e. the marginal springs: cf Wright EP & Gunston H, 1988: The Chyulu Hills Water Resources Study, Kenya: 1984-87. British Geological Survey WD/88/5C, February 1988, Wallingford, UK, 3 Vols. To be honest, the understanding that Chyulu Hills water resources are "stand alone" goes back to a colonial paper: Temperley BN, 1960: Geology and groundwater conditions in the Kibwezi-Chyulu area. Overseas Geol. Miner. Resour. 8(1): 37-52.). This misunderstanding has been perpetuated by inadequate research and possibly by the impact that "Kilimanjaro" bottled water has had on public perceptions (it is - or at least, was - bottled at Mariakani, using Mzima Springs water). I find myself shaking my head in exasperation - the authors have not seen the internal inconsistency between the statement re. Kilimanjaro's importance in water resources and the statement (quite correct) that the Chyulus exhibit 100% infiltration.
Aaaaargh! I wish they had presented geographical coordinates and data sets in their report - it deserves thorough treatment.
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