Late Pleistocene and Holocene Afromontane vegetation and headwater wetland dynamics within the Eastern Mau Forest, Kenya

Abstract

The Mau Forest Complex is Kenya's largest fragment of Afromontane forest, providing critical ecosystem services, and has been subject to intense land use changes since colonial times. It forms the upper catchment of rivers that drain into major drainage networks, thus supporting the livelihoods of millions of Kenyans and providing important wildlife areas. We present the results of a sedimentological and palynological analysis of a Late Pleistocene-Holocene sediment record of Afromontane forest change from Nyabuiyabui wetland in the Eastern Mau Forest, a highland region that has received limited geological characterization and palaeoecological study. Sedimentology, pollen, charcoal, X-ray fluorescence and radiocarbon data record environmental and ecosystem change over the last~16 000 cal a BP. The pollen record suggests Afromontane forests characterized the end of the Late Pleistocene to the Holocene with dominant taxa changing from Apodytes, Celtis, Dracaena, Hagenia and Podocarpus to Cordia, Croton, Ficus, Juniperus and Olea. The Late Holocene is characterized by a more open Afromontane forest with increased grass and herbaceous cover. Continuous Poaceae, Cyperaceae and Juncaceae vegetation currently cover the wetland and the water level has been decreasing over the recent past. Intensive agroforestry since the 1920s has reduced Afromontane forest cover as introduced taxa have increased (Pinus, Cupressus and Eucalyptus).

Influence of Gap Size on Regeneration, Structure and Species Diversity of Woody Vegetation in a Secondary Montane Forest Reserve, Kenya

“…Giving the synopsis of Table 1, a total of 41 gaps were encountered of which 7 were large gap sizes, 11 were medium gap sizes while small gap sizes dominated with 23. Additionally, Ndoinet recorded the highest number of gaps (17) with the common being small gap sizes (14).…”

“…It has an elevation of 2100 to 3300 m above sea level and receives annual rainfall amount of 2000-3000 mm [15]. The reserve is made up of three blocks; Itare, Maramara and Ndoinet [17] (Fig. 1).…”

Charcoal Whirlwinds and Post-Fire Observations in Serengeti National Park Savannahs

“…Commonly used samplers include the Modified Wilson and Cook (MWAC) and the Big Spring Number Eight (BSNE) (Mendez et al 2016) among others (Courtney-Mustaphi et al 2014a, Courtney-Mustaphi et al 2014b, Brahney et al 2020, which could be used to examine detrital organic particulates from post-fire landscapes and experimentally in the laboratory or the field. Characterization of aeolian transported inorganic and organic detritus could be done to investigate the relative contribution of aeolian transported dust and charcoal found in the study of deposits in lakes (Nelson et al 2012, Courtney Mustaphi and Pisaric 2014, Courtney Mustaphi and Pisaric 2018, Courtney Mustaphi et al 2021a, wetlands (Gillson 2006, Ekblom and Gillson 2010, Leys et al 2017, Githumbi et al, 2021a, and other accumulations (Shipton et al 2018, Li et al 2020, Williamson and Menounos 2021.…”

“…The long term spatial and temporal dynamics of charcoal from source-to-sink contributes to the empirical variable background rate of accumulation in geological records, such as lacustrine (Nelson et al 2012, Colombaroli et al 2014, palustrine (Githumbi et al 2018b(Githumbi et al , 2021a(Githumbi et al and 2021b, or marine sediments, as well as to snow and glacial ice on Mt. Kilimanjaro (Thompson et al 2002, Gabrielli et al 2014.…”

“…Charcoal entrainment, transport and deposition in the atmosphere and by surface water have yet to be characterised for any of the fire-prone ecosystems of tropical eastern Africa. The contribution of charcoal derived from fires in lowland areas to depositional environments in highland areas, including Kilimanjaro and Eastern Arc Mountains, was identified as an uncertainty that was not disentangled from local catchment fires (Schüler et al 2012, Finch et al 2017, Courtney Mustaphi et al 2021a, Courtney Mustaphi et al 2021b, Githumbi et al 2021a. The taphonomic effects of various aeolian and water flow mechanisms could produce preferentially sorted charcoal morphotype assemblages (Scott et al 2000), which have yet to be fully explored.…”