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Zonation and characteristics of the vegetation of Mt. Kenya
... The lower montane forests on Mount Kenya begin at elevations of 1200 m where agricultural settlements border protected areas, and extend up the mountain to elevations of 2500 m. The lower montane forests are similar in structure and general appearance to tropical rainforests in the Congo Basin [38]. Above the lower montane forests is the bamboo zone (Arundinaria alpina) at elevations of 2200-3200 m. ...
... The Paramo (also referred to as alpine zone) begins at approximately 4000 m and is characterized by dwarf vegetation. Further up from the Paramo is the Nival zone which is a cold desert belt consisting of mostly moraine, gravel, and stones [38]. Mount Kenya was inscribed as a UNESCO World Heritage Site in 1997 [39]. ...
... Elevation ranges for each vegetation zone on Mount Kenya, from[38] ...
Mount Kenya is one of Kenya’s ‘water towers’, the headwaters for the country’s major rivers including the Tana River and Ewaso Nyiro River, which provide water and hydroelectric power to the semiarid region. Fires affect water downstream, but are difficult to monitor given limited resources of local land management agencies. Satellite-based remote sensing has the potential to provide long term coverage of large remote areas on Mount Kenya, especially using the free Landsat data archive and moderate resolution imaging spectroradiometer (MODIS) fire products. In this study, we mapped burn scars on Mount Kenya using 30 m Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and Landsat 8 Operational Land Imager (OLI) derived dNBR (change in normalized burn ratio) and MODIS active fire detection and burned area data for fires occurring from 2004 to 2015. We also analyzed topographic position (elevation, slope, aspect) of these fires using an ASTER global digital elevation model (GDEM v2) satellite-derived 30 m digital elevation model (DEM). Results indicate that dNBR images calculated from data acquired about one year apart were able to identify large fires on Mount Kenya that match locations (and timing) of MODIS active fire points and burned areas from the same time period, but we were unable to detect smaller and/or older fires.
... It constitutes an important reservoir for plant diversity, including a substantial number of endemic and endangered species. As the publishing of the first checklist of about 140 plant species by Hooker and Oliver in 1885, numerous studies have studied plant and vegetation diversity in Mount Kenya (e.g., Bussmann, 1994;Fries & Fries, 1948;Niemelä & Pellikka, 2004;Young & Peacock, 1985). However, plant taxonomic Niemelä & Pellikka, 2004). ...
... As the publishing of the first checklist of about 140 plant species by Hooker and Oliver in 1885, numerous studies have studied plant and vegetation diversity in Mount Kenya (e.g., Bussmann, 1994;Fries & Fries, 1948;Niemelä & Pellikka, 2004;Young & Peacock, 1985). However, plant taxonomic Niemelä & Pellikka, 2004). (c) The vegetation zones of Mount Kenya from northwest to southeast in lateral view (adapted from Coe, 1967 andVECEA Team, 2012) and phylogenetic diversity of Mount Kenya have not been thoroughly analyzed, and we lack critical knowledge on the evolutionary dimension of the biodiversity in this region. ...
... We also aim to compare the diversity patterns between woody and herbaceous plants in order to a get better insight into the factors contributing to observed patterns in diversity. Table 1) (Coe, 1967;Niemelä & Pellikka, 2004;VECEA team, 2012). ...
Mount Kenya is of ecological importance in tropical east Africa due to the dramatic gradient in vegetation types that can be observed from low to high elevation zones. However, species richness and phylogenetic diversity of this mountain have not been well studied. Here, we surveyed distribution patterns for a total of 1,335 seed plants of this mountain and calculated species richness and phylogenetic diversity across seven vegetation zones. We also measured phylogenetic structure using the net relatedness index (NRI) and the nearest species index (NTI). Our results show that lower montane wet forest has the highest level of species richness, density, and phylogenetic diversity of woody plants, while lower montane dry forest has the highest level of species richness, density, and phylogenetic diversity in herbaceous plants. In total plants, NRI and NTI of four forest zones were smaller than three alpine zones. In woody plants, lower montane wet forest and upper montane forest have overdispersed phylogenetic structures. In herbaceous plants, NRI of Afro‐alpine zone and nival zone are smaller than those of bamboo zone, upper montane forest, and heath zone. We suggest that compared to open dry forest, humid forest has fewer herbaceous plants because of the closed canopy of woody plants. Woody plants may have climate‐dominated niches, whereas herbaceous plants may have edaphic and microhabitat‐dominated niches. We also proposed lower and upper montane forests with high species richness or overdispersed phylogenetic structures as the priority areas in conservation of Mount Kenya and other high mountains in the Eastern Afro‐montane biodiversity hotspot regions.
... Mount Kenya (5,199 m a.s.l.) is the highest mountain in Kenya and the second-highest in Africa, after Mount Kilimanjaro in Tanzania (Speck, 1982). There are several vegetation bands from its base to the summit, changing from forest zones, bamboo thickets, and heath zone to afro-alpine vegetation and nival zone (Coe, 1967;Niemelä and Pellikka, 2004;Zhou et al., 2018). ...
... However, fewer shrubs are present at higher elevations and forbs at these regions generally have smaller leaves (Venn et al., 2014) because leaf size is very important for the leaf energy and water balance with smaller leaves reducing boundary layer resistance (Cornelissen et al., 2003;Yang et al., 2013). Tussock grasses (Festuca sp.), sedges (Carex sp.), and other herbs just a few centimeters tall, have developed many mechanisms and structures to adapt to the harsh climate of the alpine zones such as dense hairiness, compact growth, very small leaves, and a thick cuticle (Niemelä and Pellikka, 2004). Therefore, the difference between some functional traits (e.g., maximum leaf size) of these plants will increase along the elevational gradient in the alpine zones, possibly leading to the change of the functional structure of the communities of these areas into random or even overdispersal at high elevations. ...
Compared with species richness, few studies have investigated the patterns and the relationship of phylogenetic and functional structure along elevational gradients. Here, we used general additive models to determine the trends of taxonomic diversity (species richness, SR), phylogenetic and functional diversity (PD and FD), phylogenetic structure (NRI), and functional structure (NFRI) of seed plants along the elevational gradient in Mount Kenya, which is a tropical mountain of Africa. We measured growth form, fruit type, maximum height, and maximum leaf size of each species, calculated the phylogenetic signal of each trait, and tested the Pearson correlation coefficients between NRI and NFRI of each trait. Our results showed that SR, PD, and FD decreased gradually along the elevational gradient. NRI exhibited a fluctuating pattern along the elevational gradient, while NFRI of the four functional traits showed noticeably different patterns. We concluded that the relationship between phylogenetic and functional structure in different functional traits could be congruent or mismatch along the elevational gradient. Compared with relatively conservative categorical traits (e.g., growth form and fruit type), continuous traits (e.g., height and leaf size) have a random or convergent evolutionary pattern; therefore, they could be more easily affected by the environment and possibly have higher phenotypic plasticity.
... Mount Kenya (5,199 m a.s.l.) is the highest mountain in Kenya and the second-highest in Africa, after Mount Kilimanjaro in Tanzania (Speck, 1982). There are several vegetation bands from its base to the summit, changing from forest zones, bamboo thickets, and heath zone to afro-alpine vegetation and nival zone (Coe, 1967;Niemelä and Pellikka, 2004;Zhou et al., 2018). ...
... However, fewer shrubs are present at higher elevations and forbs at these regions generally have smaller leaves (Venn et al., 2014) because leaf size is very important for the leaf energy and water balance with smaller leaves reducing boundary layer resistance ( Cornelissen et al., 2003;Yang et al., 2013). Tussock grasses (Festuca sp.), sedges (Carex sp.), and other herbs just a few centimeters tall, have developed many mechanisms and structures to adapt to the harsh climate of the alpine zones such as dense hairiness, compact growth, very small leaves, and a thick cuticle ( Niemelä and Pellikka, 2004). Therefore, the difference between some functional traits (e.g., maximum leaf size) of these plants will increase along the elevational gradient in the alpine zones, possibly leading to the change of the functional structure of the communities of these areas into random or even overdispersal at high elevations. ...
Compared to species richness, few studies have investigated the patterns and relationship of phylogenetic and functional structures along elevational gradients. Here, we used the general additive models to determine the trends of taxonomic diversity (species richness, SR), phylogenetic and functional diversity (PD and FD), phylogenetic structure net relatedness index (NRI), and functional structure net functional relatedness index (NFRI) of seed plants along the elevational gradient in Mount Kenya, a tropical mountain in Africa. We measured growth form, fruit type, maximum height, and maximum leaf size of each species, calculated the phylogenetic signal of each trait, and tested the Pearson correlation coefficients between NRI and NFRI of each trait. Our results showed that SR, PD, and FD decreased gradually along the elevational gradient. NRI exhibited a fluctuating pattern along the elevational gradient, while NFRI of the four functional traits showed noticeably different patterns. We concluded that the relationship between the phylogenetic and functional structures in different functional traits could be congruent or mismatched along the elevational gradient. Compared with relatively conservative categorical traits (e.g., growth form and fruit type), continuous traits (e.g., height and leaf size) have a random or convergent evolutionary pattern. Therefore, they could be more easily affected by the environment and possibly have higher phenotypic plasticity.
... El nuevo espacio de la puna se va a ver enriquecido con especies derivadas de las de altitudes medias, cuya radiación originó una buena cantidad de endemismos, como en el género Lupinus (Hughes & Eastwood 2006, Graham 2009). Según Cuatrecasas (1986Cuatrecasas ( , 2013 es en el Plioceno cuando se habrían diferenciado las Protoespeletiinae (Libanothamnus Ernst, Carramboa Cuatrec.) que luego lograrían la caulirósula, al igual que sucede con el género Puya (Puya raimondii) (Hornung-Leoni & Sosa 2008) y otras especies (Lobelia, Dendrosenecio) de las montañas africanas (Niemelä & Pellikka 2004). ...
... Schwarzer et al. (2010) sugieren una estrecha relación entre los efectos del vulcanismo moderno y las comunidades vegetales ante las cenizas y otros productos procedentes de la explosión del volcán Huaynaputina hace 400 años y que, en general, el vulcanismo terciario y cuaternario en el sur del Perú originó la formación de profundos valles interandinos que aislaron a las montañas con glaciares. Otros autores también sugieren tanto en Argentina (Ahumada 2002) como en el Monte Kenya (Niemelä & Pellikka 2004) que la vegetación de las altas montañas está influida tanto por los fenómenos periglaciares o criogénicos como por el vulcanismo, puesto que a las situaciones de hielodeshielo se une la presencia de cenizas volcánicas. ...
The Andean Cordillera is the second highest mountain range in the world after the Himalayas and therefore, one of the places where the cryogenic manifestations are more prominent. Tropical Andean glaciers usually present an ice-cap form, and various geomorphological forms rock glaciers, block streams, morainic deposits, cryoplanation surfaces (sometimes mixed with volcanic pumices) with polygon soils, and solifluction terraces can be distinguished in the surroundings. The study was carried out in the main glacial zones of Peru: Cordillera Blanca, Cordillera Central, Department of Puno (Allincapac and Yuracjasa), Department of Arequipa (Coropuna, Huarancante, Ampato and Imata plains), and Department of Tacna near the Tutupaca volcano. Above 4000 m (oro- and cryorotropical bioclimatic belts) we documented 152 plots using the Braun-Blanquet method, adding 287 releves from other authors from Peru, and also from Venezuela to southern Argentina and Chile. To interpret the variability, geographical distribution and vertical continuum of the associations, the concepts of basal community (BC), derived community (DC), altitudinal form and geographic race were used. Field and bibliographic tables were synthesized, and arranged using two dendrograms as a result of applying the Sorensen index to compare glacial vegetation between Peru and other regions of South America. Rock glaciers support a rupicolous vegetation dominated by Valeriana nivalis, and Saxifraga magellanica on the more humid rocks. Block streams contain specific plant communities with Xenophyllum species (X. ciliolatum, X. dactylophyllum, X. decorum, X. digitatum and X. poposum), but Chaetanthera is also very important in these biotopes across the Andes. Cryoplanation surfaces, with more stable and deep soils, present a greater diversity of plants, such as Anthochloa lepidula, Dielsiochloa floribunda, Lachemilla frigida, Mniodes coarctata, Nototriche obcuneata, N. pedicularifolia or N. turritella. On solifluction terraces and flood surfaces, communities with Festuca rigescens and Trkhophorum rigidum can be distinguished respectively. Deep clayey soils, support small pasturages of Deyeuxia minima and Aciachne pulvinata sometimes grazed, while the cushion vegetation caused by snowbreak streams is represented by Deyeuxia ovata and Werneria aretioides. From a syntaxonomical point of view, 32 Peruvian plant communities were recognized. Rock communities are the Senecio bolivarianus community mono-specific plant community on humid rocks distributed form Huancayo to Cusco, the Asplenio triphylli-Melpomenetum moniliformis ass. nova a rupiculous association installed on granitic rocks of the Cordillera Blanca, the Senecio algens community associated with the basal part of the rocks of the humid puna, and the Senecioni culcitioidis-Valerianetum nivalis a characteristic rock community usually present on andesites and basalts from Lima to Cordillera El Barroso (Tacna) [this association includes the subassociation saxifragetosum magellanicae, found on semi-permanent humid rocks, the geographic race with Draba cryptantha (Cordillera Central), the geographic race with Draba brackenridgei (near Cotahuasi Canyon, Arequipa), the geographic race with Draba cuzcoensis (near Colca Canyon, Arequipa), and the thermic ahitudinal form with Woodsia montevidensis (Callalli, Arequipa)]. The Xenophyllo-Englerocharion peruvianae alliance is represented by the following communities: Xenophyllo ciliolati-Plettkeetum cryptanthae a humid puna association present on block streams and morainic deposits with superficial stones from the Cordillera Blanca to Allincapac (Puno) [this association includes an altitudinal form with Anticona glareophila, from the limits of the vegetation of the Cordillera Central, a variant of semi-fixed blocks with Xenophyllum digitatum, a variant of mobile blocks with Xenophyllum ciliolatum, a derived community (DC) with Chaetanthera cochlearzfolia from Central Peru, found on clayey places that will evolve to the polygon soils colonized by the Stangeo rhizanthae-Weberbaueretum rosulantis association, and a DC with Valeriana globularis and Anthochloa lepidula on the same environments from southern Peru], and the Foci gymnanthaCerastium peruvianum community, documented on volcanic conglomerates from Callalli (Arequipa). Nototricho obcuneatae-Xenophylletum poposi installed on semi-fixed blocks of the altiplano of Peru and Bolivia in drysubhumid climate (its variability presents the sub-associations valerianetosum nivalis as a rupiculous aspect, and mniodetosum coarctatae on lightly sloping polygon soils), Nototricho-Mniodetum coarctatae ass. nova cryorotropical vegetation on flat polygon soils enriched with the volcanic pumices of the altiplano, and the Belloo piptolepis-Dissanthelietum calycini that indicates wetter soils without volcanic pumices in the altiplano belong to the Nototrichion obcuneatae alliance. The Deyeuxion minimae alliance indicates deeper and more humid soils, where we can differentiate five associations: Nototricho pinnatae-Lachemilletum frigidae present on the rock cornices and polygon soils coming from intrusive geologic materials of the Cordillera Blanca, Pycnophyllo mollis-Festucetum rigescentis very typical on solifluction terraces of the humid puna of Peruand Bolivia, Deyeuxio minimae-Trichophoretum rigidae on flooded surfaces of the humid Peruvian Andes, Azorello diapensioidis-Deyeuxietum minimae on humid, deep and clayey cryogenic soils, sometimes with very little superficial stones [this association includes an altitudinal form with Deyeuxia rigida, an ahitudinal form with Pycnophyllum molle, a variant on incipient solifluction terraces with Dissanthelium macusaniense, and another variant on deep and humid soils with Werneria nubigena], and Gnaphalio badii-Aciachnetum pulvinatae grazed vegetation in the orotropical belt. Finally, Deyeuxio ovatae-Wernerietum aretioidis ass. nova is a cushion association belonging to the Plantagini-Distichietea class occurring between 4800 and 5000 m a.s.l. To study the relationships between plant communities and some selected climatic parameters (T, M, m, It, P, Pm and Hm see abbreviations of the Table 6), we have made a biplot from a Principal Component Analyses for each plant community group (rock communities, Xenophyllo-Englerocharion, Nototrichion obcuneatae, and Deyeuxion minimae and other syntaxa. Plant communities placed at high altitude or in dry puna (Oruro-Arequiperia biogeographic province) are linked with the smaller values of the lowest mean temperature of the coldest month (m), while those placed in the humid puna (Ancashino-Paceria biogeographic province) are linked with the highest values of the highest mean temperature of the coldest month (M). Finally, the syntaxa Empetro rubrum-Balecetea gummiferae, Hamadryo kingii-Oreopolion glacialis, Leucherio hahnii-Nassauvietum juniperinae and Empetro rubrum-Oreopoletum glacialis, described earlier from Southern Patagonia, are typified.
... East Africa has several prominent mountains ranges and massives, whereas there are very few major mountains farther west than Cameroon. this is confirmed by the altitude distributions of the records of this genus: only the southern species D. capensis has been recorded at altitudes <500 m, whereas the genus has been recorded as high as 4450 m (D. atrimas), which is close to the upper limit of substantial vegetation, bordering on the nival zone of Mount kenya (Niemelä & Pellikka, 2004). As would be expected for a mainly tropical continent, the records show few obvious trends with respect to phenology (table 2), this is a strong contrast to the situation in Europe (e.g., Skartveit 1996a) where Dilophus species have very distinctive flight periods. ...
We revise the Afrotropical species of the genus Dilophus Meigen, redescribing each species. Previous Afrotropical records
of the Palaearctic species Dilophus antipedalis Wiedemann and Dilophus femoratus Meigen are found to be erroneous,
both these represent undescribed species, the former is distributed in the mountains along the southern Rift Valley
and described as Dilophus riftensis sp.n., specimens recorded as the latter from Madagascar is described as Dilophus
malagasicus sp.n.. Furthermore, one montane or alpine species apparently endemic to Ethiopia is described, Dilophus
baleensis sp.n.. Philia splendens Hardy, 1951 is found to be a junior synonym of Dilophus bicolor Wiedemann, 1821. We
summarise what is known about the distribution and phenology of these species in the Afrotropical ecozone
... It belongs to the Eastern Afromontane biodiversity hotspot, which is one of the two diversity hotpots in east Africa (Mittermeier et al. 2011). This mountain harbours about 1500 vascular plants and a variety of vegetation zones along the altitudinal gradient (Rehder et al. 1988;Niemelä and Pellikka 2004;Zhou et al. 2022a), which is an ideal natural experimental area for the study of plant diversity variations along altitudinal gradients (Zhou et al. 2019a,b). Here, we analyze two datasets of plant distribution of this mountain from field surveys and empirical integrated method. ...
Field surveys and empirical integrated methods are commonly used in the ecological research to understand the altitudinal pattern of plant diversity of mountains. However, few studies have compared the differences between the two methods on the same scale. Here, we addressed and compared the altitudinal patterns of species richness (SR), phylogenetic diversity (PD), the standardized effect size of phylogenetic diversity (PDses) and mean phylogenetic distance (MPDses) of about 580 angiosperms growing on Mount Kenya from two independent datasets: one is based on our several times field surveys in this mountain and another one is based on empirical data integrated from literatures. We found that the altitudinal diversity patterns of field surveys dataset were consistent with the empirical integrated dataset. Both SR and PD showed hump-shaped patterns along the altitude, and both PDses and MPDses showed monotonically decreasing patterns along the altitude. The ratio of diversity between field surveys dataset and empirical integrated dataset were gradually increase along the altitude. Our research provides new insight for understanding the altitudinal diversity patterns of plants of a tropical mountain.
... There are six major vegetation zones that have been classified according to altitude and floristic composition. They are montane forest 1600-2400 m; bamboo thickets 2400-2850 m; Hagenia-Hypericum woodland 2850-3000 m; Erica bushland/shrubland 3000-3300 m; alpine zone 3300-4350 m and nival zone 4350-5199 m [23]. The FS has heterogeneous vegetation that is characterized by indigenous and exotic tree species, bamboo, shrubs and grasslands ( Figure 1). ...
Climate change, vegetation dynamics, human activities and forest management influence the occurrence of fires. This study investigated the spatio-temporal variability of the Vegetation Condition Index (VCI) and its influence on fire occurrence in three different land use types in Mount Kenya Forest Reserve and National Park (MKFRNP): National Park (NP), Forest Stations (FS) and Farmlands (FL). The study used MODIS satellite data to obtain the Normalized Difference Vegetation Index (NDVI), the VCI, the number of fires and the burnt area. The specific objectives of this research were (i) to examine the spatio-temporal variability of VCI, fire occurrence and burnt area in MKFRNP from 2003 to 2018 and (ii) to explore the relationship between VCI, fire occurrence and burnt area in different areas of the MKFRNP (NP, FS and FL). The findings show that even though fires occur throughout the year in MKFRNP, most of the fires occur during dry seasons. The relationship between spatio-temporal fire occurrence and VCI distribution is different for each land use type. In the FL, the probability of fire ignition and the number of fires per month was more or less the same irrespective of the VCI because of the traditional use of fire as a land management tool. However, the probability of fire ignition and the number of fires per month is high in the NP and FS when the VCI is below 50% (drought), especially in the dry seasons, when and where the impact of meteorological conditions and climate have much more impact than human activities. In addition to the efforts already made by communities, KFS and KWS in the fire fighting and monitoring system, satellite data can be useful to acquire accurate and timely information on the VCI and the likely spatio-temporal occurrence of fires in order to be prepared in the most fire-prone periods and improve fire management, the planning of resources and fire suppression activities in MKFRNP.
... African specimens collected by the author, C. Decock, originate from the Mount Elgon range, Kenya, the Kahuzi Biega mountain range, eastern Democratic Republic of Congo, and several spots of dense rain forest of the Guineo-Congolian phytogeographic region in Gabon. The nomenclature of the successive vegetation zones at Mt Elgon follows Niemelä and Pellikka (2014) and Kindt et al. (2011). ...
Poria eichelbaumii, a long-forgotten name, is transferred to Haploporus based on studies of the type specimen, comparison with new collections, and evidences from both morphology and phylogeny. The species is redescribed and illustrated. Haploporus grandisporus is described as new, on the basis of concordant morphological and phylogenetic species concepts. These two species form two very closely related clades within the Haploporus lineage in [28S-ITS]-based phylogenetic inferences. Haploporus eichelbaumii and H. grandisporus are distinguished by the size of their basidiospores (11.5-14.5 × 5.0-6.0 μm, average = 12.7 × 5.8 μm, vs 14-17.5 × 6.0-7.3 μm, average 15.4 × 6.6 μm), the size of their pores (2.5-3.5 / mm, vs 1.5-2.5 / mm), and, likely, divergent autecologies. Although both species occur in montane ecosystems of the eastern African rift, the data so far available suggest they occupy different habitats. Haploporus eichelbaumii has wider distribution, spanning over both branches of the eastern rift, at elevation~1500-2500 masl, in various vegetation types, mostly on small-sized dead branches or twigs, and dead bamboo culms. It is known so far from Kenya, Tanzania, and Malawi to the East, and western Burundi, western Uganda, and Eastern Congo (DRC) in the Albertine mountain ranges. Haploporus grandisporus is known, hitherto, only from the Eastern slopes of Mount Elgon in Kenya, at the timberline, 2900-3200 masl, mostly on dead heather branches (Erica arborea, Ericaceae) in heather thickets. Haploporus nanosporus is currently the third known Haploporus species from tropical Africa, known from the western edge of the Guineo-Congolian rain forest in Gabon and Cameroon. This species is also redescribed and illustrated.
... Therefore, correlating heavy metal concentration with environmental factors such as wind, temperature, or precipitation data proved difficult. However, we note that the eastern slope (Chogoria) receives more precipitation than the western slope (Naro Moru) (Niemelä and Pellikka 2004). The lower montane forest separated agricultural farms with other forest vegetation types. ...
Mountains are the preferred sites for studying long-range atmospheric transportation and deposition of heavy metals, due to their isolation and steep temperature decrease that favors cold trapping and condensation of particulate forms of heavy metals. Any enrichment of heavy metals in mountains is presumed to primarily occur through atmospheric deposition. In this particular study, we assessed the status of 27 subsurface soils collected along two elevation gradients of Mt. Kenya using enrichment factors (EFs) as the ecological risk assessments. The collected soils were analyzed for total organic carbon, zinc (Zn), iron (Fe), manganese (Mn), and copper (Cu). The mean concentration of Mn, Fe, Zn, and Cu was 0.376 mg/kg, 47.6 mg/kg, 12.3 mg/kg, and 4.88 mg/kg in Chogoria and 0.560 mg/kg, 113 mg/kg, 12.7 mg/kg, and 2.70 mg/kg in Naro Moru respectively. These concentrations were below the US-EPA maximum permissible levels for soils, implying that the levels recorded had low toxicity. Meanwhile, the mean enrichment factors for Mn, Cu, and Zn were 0.447, 131, and 78.8 in Chogoria and 0.463, 38.9, and 53.0 in Naro Moru respectively. This implied that Zn and Cu in Chogoria sites were extremely enriched, while in Naro Moru, enrichment levels ranged from significant to extreme. However, Mn was found to have minimal enrichment in all the sites. Lower montane forest and bamboo zone recorded relatively high enrichment due to distance from source of pollution. Ericaceous zone also had high mean enrichment due to influence of wind which favors higher deposition at mid-elevations.
... Taller life-forms like trees and shrubs are confined to the lower elevations, and similar patterns of lianas and ferns are coupled to that of trees (Carpenter, 2005;Kluge et al., 2017), leading to a significant decrease in the proportion of woody plants along the elevation gradient, and this reflects physiological adaptations to high elevation and alpine environments (Kluge et al., 2017;Körner, 2003). Analogous to most mountains of the world (Steinbauer et al., 2016), such as Andes (Kessler, 2000), Himalayas (Kluge et al., 2017;Vetaas & Grytnes, 2002), and Hengduan Mountains (Zhang, Zhang, Boufford, & Sun, 2009), endemic species are confined to high elevations in the tropical African mountains (Hedberg, 1969;Morton, 1972 (Coe, 1967;Niemelä & Pellikka, 2004;Zhou et al., 2018). ...
The research about species richness pattern and elevational Rapoport's rule (ERR) have been carried out mostly in the temperate regions in the recent years and scarcely in the tropical mountains; meanwhile, it is unclear whether the ERR is consistent among different life‐forms and phytogeographic affinities. Here, we compiled a database of plant species of Mount Kenya, a tropical mountain of East Africa, and divided these species into twelve groups depending on the life‐form and phytogeographic affinity of each species. We inspected the species richness pattern of each group along the elevation gradient and also tested ERR of each group using Stevens' method. Our results showed that species richness of the total species showed a positively skewed (hump‐shaped) pattern along the elevation gradient and different life‐forms and phytogeographic affinities showed similar hump‐shaped patterns as the total species. The average elevation range size of the total species and herbaceous species showed increasing patterns along the elevation gradient, while lycophytes and ferns, and woody species showed an obvious downward trend after peaking in the high elevation regions. We concluded that the widely distributed herbaceous species which also have broad elevation range sizes are more applicable to ERR, while the narrowly distributed woody species with small elevation range sizes occurring in the higher elevations could reverse ERR. Therefore, we concluded that the ERR is not consistent among different organisms in the same region.
... However, it is costly and seems not suitable for practical application in poor conditions of local mountainous areas North Vietnam as in the present study site. Elevation above sea level is a prerequisite condition [12], which we cannot modify like temperature and humidity. Therefore, three conditions including air temperature, annual precipitation, and elevation above sea level were recognized as prerequisite conditions for planting C. impressinervis in Vietnam. ...
Camellia impressinervis is known as a golden camellia, naturally distributing in China and Vietnam. Leaves and flowers of golden camellias contain active ingredients such as polysaccharides, polyphenols, saponins, and flavonoids. It was found to be able to inhibit the transplanted cancer, lower blood lipid, lower cholesterol, and prevent atherosclerosis. Market price of dry flowers of golden camellias in Vietnam is high, up to 700 US$/kg. This work was to identify suitable planting areas for C. impressinervis in Vietnam. Natural conditions, where C. impressinervis naturally distributes, were used for mapping, including elevation above sea level, annual precipitation, and annual air temperature. Each condition was classified to four levels as “very suitable”, “suitable”, “less suitable”, and “not suitable” for planting. Three corresponding digital maps were used for mapping. The results indicated that 72,781 ha accounting for 32.3% total land area of the study site was classified as “very suitable” for planting C. impressinervis. The “suitable” areas accounted for 34.2% and the not suitable areas accounted for 33.5% total land area. There was no area belonging to “less suitable”. It is recommended that C. impressinervis should be planted in “very suitable” areas and may be extended some to “suitable” areas. However, it should be widely planted only after carefully studying on cultivar selection, seedling production, and planting and tending techniques with consultation by local authorities.
... Studies range from repeated surveys of air photographs [34] or permanent vegetation plots [24-26, 28] to sediment-based studies that examine change since the Pleistocene [35][36][37][38][39][40][41]. To date, there is one published pollen record (Hobley Valley mire [42]) from the alpine zone (~4000-5000 m asl [43]) located in an unglaciated valley on the windward mountainside; however this site has few geochronological age determinations. High-elevation lake sediment studies of Mount Kenya have focused on glacier histories [8,[44][45], sediment isotopes [46][47][48] and carbon cycling [40]. ...
High-elevation ecosystems, such as those on Mount Kenya are undergoing significant changes, with accelerated glacial ice losses over the twentieth century creating new space for alpine plants to establish. These ecosystems respond rapidly to climatic variability and within decades of glacial retreat, Afroalpine pioneering taxa stabilize barren land and facilitate soil development, promoting complex patches of alpine vegetation. Periglacial lake sediment records can be used to examine centennial and millennial scale variations in alpine and montane vegetation compositions. Here we present a 5300-year composite pollen record from an alpine tarn (4370 m asl) in the Hausberg Valley of Mount Kenya. Overall, the record shows little apparent variation in the pollen assemblage through time with abundant montane forest taxa derived and transported from mid elevations, notably high abundances of aerophilous Podocarpus pollen. Afroalpine taxa included Alchemilla, Helichrysum and Dendrosenecio-type, reflecting local vegetation cover. Pollen from the ericaceous zone was present throughout the record and Poaceae percentages were high, similar to other high elevation pollen records from eastern Africa. The Oblong Tarn record pollen assemblage composition and abundances of Podocarpus and Poaceae since the late Holocene (~4000 cal yr BP-present) are similar to pollen records from mid-to-high elevation sites of nearby high mountains such as Mount Elgon and Kilimanjaro. These results suggest a significant amount of uphill pollen transport with only minor apparent variation in local taxa. Slight decreasing trends in alpine and ericaceous taxonomic groups show a long-term response to global late Holocene cooling and a step decrease in rate of change estimated from the pollen assemblages at 3100 cal yr BP in response to regional hydroclimatic variability. Changes in the principal component axis scores of the pollen assemblage were coherent with an independent mid-elevation temperature reconstruction, which supported the strong influence of uphill pollen transport from montane forest vegetation and association between temperatures and montane vegetation dynamics. Pollen accumulation rates showed some variability related to minerogenic sediment input to the lake. The Oblong Tarn pollen record provides an indication of long term vegetation change atop Mount Kenya showing some decreases in local alpine and ericaceous taxa from 5300–3100 cal yr BP and minor centennial-scale variability of montane taxa from mid elevation forests. The record highlights potentials, challenges and opportunities for the use of proglacial lacustrine sediment to examine vegetation change on prominent mountain massifs.
... In the nival zone, corresponding to land cover class I and to a lesser extent to classes G and J, soil is mostly glacial moraine and vegetation is sparse (Niemelä and Pellikka 2004). These large extents of bare soil can be caused by solifluction, or frost heaving, and are common above elevations of 4100-4200 m a.s.l. in East African mountains (Hedberg 1964). ...
We used remotely-sensed multi-spectral imagery to develop a map of Afroalpine vegetation in the Bale Mountains in southern Ethiopia. This is the largest and most intact area of Afroalpine vegetation over 3000 m a.s.l., and harbours many endemic flora and fauna, including several Bale endemics and the largest population of the rarest canid in the world, the Ethiopian wolf Canis simensis.
We isolated 23 spectrally separable land cover classes using unsupervised classification. Quantitative vegetation surveys provide descriptions of each class. All classes for which sufficient ground-truthing data existed (n = 17) were statistically distinct in terms of substrate, species composition, height and/or vegetation cover. The majority of classes identified discrete vegetation communities, while some represented the interface of different land cover types which occurred in the same pixel.
The map provides a comprehensive baseline from which to monitor the effects of anthropogenic activities and global warming on the extent and degradation of alpine vegetation in the Bale Mountains, and is a valuable tool for planning natural resource use management within the Bale Mountains National Park. It also provides the context for research into the habitat preferences and ecology of the endemic wildlife which the park was established to protect.
... 3) shows that the upper tree limit on Mount Kenya is 4,000 m a.s.l. (NIEMELÄ a. PELLIKKA 2004) and in Ecuador it is 4,200 m a.s.l. (BENDIX a. RAFIQPOOR 2001;LAUER et al. 2003). ...
Background Numerous studies have been conducted on species richness patterns along elevation gradients in temperate, tropical and sub-tropical mountains. However, few studies have been done to evaluate the combined effect of area and environmental heterogeneity (abiotic and biotic) on species richness. Numerous ecological studies have also failed to quantify environmental heterogeneity which we have done in this research. In this research, we studied the impact of area on environmental heterogeneity on species richness by considering the climate factors, annual mean temperature (AMT), annual mean precipitation (AMP), annual total solar radiation (ATSR), and Soil factors, soil organic carbon (SOC), Soil total nitrogen (STN), Soil extractable phosphorous (SEP), and Soil extractable potassium (SEK).Results Our analysis showed that species richness had a skewed hump-shaped pattern, with the highest species richness being at mid-elevation. The results also showed that climate factors had a strong positive correlation with species richness in relation to area as compared to soil factors. We also found that soil factors could be used to explain the species richness when combined rather than being interpreted individually. This study has showed that area could have profound effect on environmental heterogeneity therefore shaping species richness pattern along the elevation gradient in Mount Kenya.Conclusion The hump shaped species richness pattern can be due to the Ecophysiological constraints for example, low temperatures as elevation increases. The high species richness at the mid-elevation is because this zone has a large land area and also acts as transition zone between the extremes of the upper elevation range and lower elevation and species from either side can coexist since the environmental conditions are on the lower and higher limits for the existence of these plant species.
Historical analysis of wildfire frequency, intensity, size, season, and type helps to determine the fire regime and the impacts of human activity in a region. Information about the temporal and spatial distribution of forest fires can help guide the formulation of integrated fire management policies. Mt Kenya Forest provides ecosystem services that sustain the livelihoods of local communities. However, forest fires have negatively affected sustainability of these services. This study describes recent fire patterns in the Mt Kenya forest. Field observations recorded by the Kenya Forest Service from 1980 to 2015 are analyzed. In addition, trends in fire occurrence over time and in relation to vegetation type are described. Key findings evidence a fire-prone period in February and March and a decrease of total burned area during the study period. Bush and grassland were the most fire-prone vegetation, and the fire regime varied in each forest station. Further, field observations were compared with satellite data. Some discrepancies between the field and satellite fire data were observed, especially for larger fires. These findings confirm the importance of monitoring efforts by the Kenya Forest Service to inform wildfire management. Recommendations are made on ways to improve fire monitoring and fire suppression efforts.
The accurate and consistent identification of fossil pollen is essential to allow robust inferences to be drawn with regard to past vegetation and climate change. Identifications are best achieved through the direct inspection of reference material. Most substantial reference collections are located at research institutions in Europe or North America, which restricts access for researchers trying to advance palynology in less developed countries. Due to the development of digital imaging and fast internet access it is now possible to produce high quality images from pollen and spore reference collections and make them globally available. In this pollen and spore atlas we contribute to this growing body of work by presenting images of 240 pollen types (in 202 genera and ∼79 families) and 30 spore types (in 25 genera and ∼17 families) from a wide range of different vegetation types originating from the Kilimanjaro area and tropical East Africa. We provide an overview on the range of pollen and spore types commonly found in Last Glacial and Holocene sedimentary archives in studies from the Kilimanjaro area and tropical East Africa. Besides a pollen key, detailed information is given on pollination, habitus and habitat which all support the interpretation and environmental reconstructions from pollen records. The atlas will serve as useful guide for palynological investigations, aiming at detailed and comprehensive reconstruction of past vegetation, environmental and climate change in tropical East Africa.
Pollen and charcoal data generated from a 1469cm core, radiocarbon dated to 26,43014C yr BP, recovered from Rumuiku Swamp on the southeast of Mount Kenya, are used to document changes in the distribution and composition of montane vegetation and fire regimes over the Late Quaternary. Throughout the transition from the Last Glacial Maximum (LGM), high resolution (sub-centennial scale) analysis documents a highly dynamic ecosystem and fire regime. The pollen record shows that under a cool, but rather moist LGM climate, Ericaceae and Stoebe species shifted down-slope more than 1000m relative to the present day. Rather than simple altitudinal lowering of current vegetation zonation, these taxa formed a vegetation assemblage that mixed high altitude components with relatively lowland taxa; in particular Juniperus that is presently found at altitudes lower than the study site, but on the drier side of Mount Kenya. There is noticeable addition and co-dominance of Hagenia to the ecosystem from 20,50014C yr BP, until around 14,00014C yr BP when a mix of Ericaceous Belt and upper montane forest taxa, such as Artemisia, Polycias, Schefflera and Stoebe, dominated the initial development of montane forest. Reduced levels of Hagenia, Juniperus, Olea and Podocarpus are recorded about the time of the Younger Dryas with highly variable presence of more mesic taxa such as Polyscias and Schefflera. This development of montane forest over the Late Pleistocene to Holocene transition reflects a significant reorganization of the ecosystem composition that was heavily influenced by a variable fire regime. Shifts in vegetation composition reflect the onset of a warmer moist climate from the beginning of Holocene, as mixed montane forest became more established. The latter part of the Holocene registers human impact and forest clearance with increased anthropogenic impact marked by a transition to open vegetation and increased fire frequency.
Kenyan forests are biologically rich and harbour high concentrations of endemic species. Forests contain lowland rainforest in western Kenya, and montane forest in the central and western highlands and on higher hills and mountains. Forest classification done by describing dominant species and environmental features of different forest types summarises these forests in six main blocks: the volcanic mountains, the western plateau, the northern mountains, the coastal forests, the southern hills and the riverine forests. Since Kenyan forests are influenced by the farming and herding practices of the local inhabitants, many Kenyan forests are cultural rather than natural entities. However, they still support a forest cover of solely or mainly indigenous species. This is also why most forests are highly fragmented and under pressure - lowland forests are the first forests to be cleared for agriculture and present population pressure is making the forests more and more fragmented and degraded.
Species composition, physiognomy, and plant diversity of the less known cloud forests in Yunnan were studied based on data
collected from 35 sample plots at seven sites. In floristic composition, the cloud forests are mainly comprised of Fagaceae,
Ericaceae, Vacciniaceae, Aceraceae, Magnoliaceae, Theaceae, Aquifoliaceae, Illiciaceae, Lauraceae, and Rosaceae. Physiognomically,
the forests are dominated by tree and shrub species. Lianas are rare in the forests. The plants with microphyllous or nanophyllous
leaves comprise 44.32–63.46% of the total species, and plants with an entire leaf margin account for more than 50% of the
tree and shrub species. There are few tree and shrub species with a drip tip leaf apex and papery leaves. Evergreen species
make up more than 75% of the total tree and shrub species. In a 2,500m2 sampling area, the number of vascular species ranged between 57 and 110; Simpson’s diversity index ranged from 0.7719 to
0.9544, Shannon–Winner’s diversity index from 1.8251 to 3.2905, and Pielou’s evenness index from 0.5836 to 0.8982 for trees.
The cloud forests in Yunnan are physiognomically similar to the tropical cloud forests in America and Southeast Asia. They
very much resemble the mountain dwarf mossy forest in Hainan Island, southeastern China, and the Mountain ericaceous forests
in the Malay Peninsula. The cloud forests in Yunnan are considered to be developed, as are the tropical upper montane cloud
forests in Asia.
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