147:. Lake Naivasha is an important source of water in a semi-arid environment, and supports export-oriented horticulture and floriculture businesses as well as tourism. Malewa River water quality has deteriorated because of more human activities in the upper catchment. Long-term effects of this on the percentage of rainfall getting into Lake Naivasha are not clear. Possibly in low-rainfall years the percentage will drop because of water abstraction, while in high-rainfall years the percentage will go up because of cultivated soils having a lower water-holding capacity and the introduction of more 100% runoff surfaces like tarmac roads and iron sheets, etc.
187:
farmers since the 1960s. They have ploughed much of the land to grow maize, wheat, cabbage and potatoes. The wetlands have mostly been drained. Where drainage has not been deliberate, the trees planted for poles and firewood have absorbed the water. The trend is towards more intensive cultivation of
196:
The river is threatened by deforestation and siltation, increasing diversion of water for irrigation, and pollution by fertilizers and pesticides. In August 1997 sediment-laden plumes of Malewa river water extended about 500 metres (1,600 ft) into Lake
Naivasha. Access to natural resources and
170:
The
Aberdare range receives about 1,200 millimetres (47 in) of rain annually and has large areas of dense forest. The highlands drained by the Malewa are volcanic and contribute sodium and calcium to the water through chemical weathering of the rocks. Sulphate in the water comes from the
171:
atmosphere. The floor of the Rift Valley gets just 600 millimetres (24 in) each year and is mainly covered by scrub, with some bare soil. Rainfall peaks between April and June and again in
October and November. Erosion is highest in these months.
350:
155:
The Malewa River catchment of 1,730 square kilometres (670 sq mi) provides about 90% of the water flowing into Lake
Naivasha, with most of the remainder coming from the
183:. At one time the plateau was almost completely covered in tussocky grassland with very few trees. The stream valleys had many tussocky bogs. The plateau has been settled by
524:
397:
159:. The headwaters of the main channel of the Malewa originate at an elevation of 3,700 metres (12,100 ft) in the Nyandarua (Aberdare) mountains. Its tributary the
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is common and poverty is widespread. Improvements to resource management practices could cause major improvements in reducing pollution and erosion.
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467:"Hydrological analysis of Malewa watershed as a basis for implementing payment for environmental services (PES)"
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760:
167:, Simba, Nyairoko and Ol Kalou. The rivers in the Malewa basin are relatively shallow but are all perennial.
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898:
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is fed by several small rivers running from the slopes of the
Aberdares. Other tributaries are the
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451:"Lake Naivasha - Malewa River Basin Integrated Water Resource Management (IWRM) Programme"
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379:. International Institute for Aerospace Survey and Earth Sciences, Netherlands
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411:
Biological invaders in inland waters: profiles, distribution and threats
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847:
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466:
376:
862:
857:
842:
572:
377:"Erosion assessment for large basins using remote sensing and GIS"
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469:. Jomo Kenyatta University of Agriculture and Technology, Kenya
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The Malewa River is fed by streams that run through the
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351:"Kinangop Plateau Nature Reserve Management Plan"
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484:East African ecosystems and their conservation
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84:1,730 square kilometres (670 sq mi)
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396:: CS1 maint: multiple names: authors list (
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197:markets is not equitable in the region.
882:Paleontological and archeological sites
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131:rises in the western slopes of the
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349:Darwin Initiative (2006-07-05).
139:and flows south and west into
43: • coordinates
1:
797:Mount Kipipiri Forest Reserve
787:Lake Bogoria National Reserve
777:Kerio Valley National Reserve
27:Physical characteristics
817:Mount Longonot National Park
465:Ogweno, Luke Philip (2009).
336:"KE004: Kinangop grasslands"
807:Lake Naivasha National Park
487:. Oxford University Press.
375:Hamududu, Byman, H (1998).
188:food crops and cash crops.
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802:Kigio Wildlife Conservancy
782:Lake Baringo National Park
812:Hell's Gate National Park
792:Lake Nakuru National Park
429:Harper, David M. (2003).
534:Great Rift Valley, Kenya
334:Birdlife International.
115: • right
822:Mount Suswa Conservancy
103: • left
306:Lake Naivasha - Malewa
294:Darwin Initiative 2006
282:Birdlife International
65:0.724778°S 36.353288°E
761:Southern Ewaso Ng'iro
607:Hills and escarpments
481:Young, T. P. (1996).
827:Shompole Conservancy
432:Lake Naivasha, Kenya
70:-0.724778; 36.353288
624:Nguruman Escarpment
406:Gherardi, Francesca
89:Basin features
61: /
770:Conservation areas
629:Losiolo Escarpment
937:
936:
614:Elgeyo Escarpment
421:978-1-4020-6028-1
145:Great Rift Valley
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199:Water conflict
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133:Aberdare Range
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363:on 2012-04-25
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217:Gherardi 2007
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141:Lake Naivasha
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471:. Retrieved
455:. Retrieved
453:. WWF Global
435:. Springer.
431:
414:. Springer.
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381:. Retrieved
365:. Retrieved
358:the original
339:. Retrieved
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157:Gilgil River
154:
129:Malewa River
128:
126:
22:Malewa River
894:Aiyangiyang
639:Ngong Hills
598:Mount Suswa
318:Ogweno 2009
246:Harper 2003
234:Harper 2003
94:Tributaries
68: /
909:Koobi Fora
685:Elmenteita
473:2012-01-02
457:2011-01-02
383:2012-01-02
367:2011-12-28
341:2011-12-28
258:Young 1996
205:References
81:Basin size
56:36°21′12″E
731:Ol Arabel
541:Volcanoes
151:Catchment
53:0°43′29″S
944:Category
919:Lothagam
899:Amboseli
868:Naivasha
736:Perkerra
690:Naivasha
593:Longonot
578:Menengai
553:Namarunu
408:(2007).
392:cite web
175:Land use
914:Laetoli
853:Marigat
848:Kinyang
756:Turasha
741:Waseges
675:Bogoria
670:Baringo
660:Turkana
588:Olkaria
327:Sources
165:Turasha
161:Wanjohi
143:in the
120:Wanjohi
108:Turasha
873:Magadi
863:Gilgil
858:Nakuru
843:Kapedo
751:Malewa
746:Gilgil
716:Suguta
709:Rivers
700:Natron
695:Magadi
680:Nakuru
665:Logipi
583:Eburru
573:Korosi
563:Silali
491:
439:
418:
192:Issues
185:Kikuyu
97:
37:
904:Karsa
721:Kerio
653:Lakes
361:(PDF)
354:(PDF)
137:Kenya
33:Mouth
16:River
726:Molo
568:Paka
489:ISBN
437:ISBN
416:ISBN
398:link
127:The
135:in
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394:}}
390:{{
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272:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.