KIBAUNI HILL FOREST PLANT ASSESSMENT: FLORISTIC ... Forest Plant... · services that people are...

KIBAUNI HILL FOREST PLANT ASSESSMENT: FLORISTIC COMPOSITION,

STRUCTURE AND CONSERVATION STATUS

Final Report

By: Vincent Mainga1, Winfred Musila2, John Kimeu2, Christopher Chesire2 James

Kariuki1

March 2012

1. Green Resources Initiative, 2. National Museums of Kenya

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EXECUTIVE SUMMARY

Kibauni Hill forest is a gazette dryland forest occurring in Yathui, Machakos District, Eastern Kenya.

A botanical survey was conducted to document the floristic composition, structure and

conservation status of Kibauni Forest. Vegetation sampling was done along five transects (T1-T5)

during both dry (08th October -11th October 2011) and wet (14th December - 17th December 2011)

seasons. The transects were spanning from the forest edge to the hilltop and along an altitudinal

gradient. Transects T1, T2, and T3 were set on the leeward side while T4 and T5 were set on the

windward side of the hill. Sampling zones were established along each transect and within each

sampling zone, triplicate plots of 20 by 20 m were sampled. A total of 24 plots were demarcated.

In each plot, the plants - trees, shrubs and herbs were recorded in order to provide an overview of

plant diversity, composition and structure. The canopy cover and height within the three life form

layers i.e. herb, shrub and tree layers were estimated in each plot. Diameter at breast height

(DBH) was measured for all trees with heights exceeding 5 meters so as to assess the trees

population structure. Threats facing Kibauni forest were assessed by quantifying the indicators of

disturbance. Overall, a total number of 155 plant species where recorded during the 2 seasons

belonging to 48 families and 117 genera. The five species were found to be Kenyan endemics and

two of them are rated as rare or vulnerable. Trees were the most dominant life form occupying

over 41% of entire area during the dry season while herbs (39%) were most dominant in the wet

season. A comparison of stem size distribution between trees on the windward and leeward side

showed that the tree population structure on the leeward side is more stable than on the was

inverse j-shaped but the windward side. This could have been caused by high disturbance levels on

the windward side. Kibauni Hill is surrounded by high human population and most are poor forcing

them to depend heavily on the natural resources of Kibauni Hill. A number of threats facing

Kibauni Hills plants were observed. This included cattle grazing, tree poaching, firewood collection,

charcoal burning, debarking of herbal plants and soil erosion. In conclusion, Kibauni Hill forest is a

dry forest with low stature and open canopy. The forest serves as refugium of plant diversity

however, it is highly threatened by anthropogenic interference especially on the windward side of

the forest. The survival of the plant diversity is therefore at risk and following recommendations

are proposed to safeguard it:

1. There is need to create awareness and educate the local communities on the importance

of the forest and the need to conserve the forest.

2. Though the extent and magnitude of identified threats was not measured, there is need to

control the on-going illegal activities through strict policing and surveillance.

3. Alternative means of livelihoods e.g. bee keeping, should be promoted to reduce over

dependence on the forest resources.

4. A participatory management plan for Kibauni Hill forest should be developed and

implemented involving all the stakeholders.

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5. Forest restoration efforts involving the forest adjacent communities should be enhanced

especially on the windward side of the hill which is highly degraded.

6. There is need to boost conservation efforts especially for the four endemic plant species

including two rare or one vulnerable species recorded.

7. The sampled plots should be monitored on a regular basis to inform managers on the

forest status. All the plots sampled were georeferenced (Appendix 1) and can be used as

Permanent Sample Plots (PSPs) for monitoring purposes in order to establish any trends in

species, occurrence, distribution or abundance in time, especially in the face of climate

change and any other (human-driven) disturbances.

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ACKNOWLEDGEMENTS

We would like to thank the Rufford small grants for Nature for their financial support that saw the

facilitation of this work. We are also grateful to the National Museums of Kenya Dr. Winfred

Musila, Mr. John Kimeu and Mr. Christopher Chesire as well as Green Resources staff Mr. Vincent

Mainga and James Kariuki for their tireless contribution towards the success of this project. Mr.

Patrick Mung’ala who hosted the research team during the field survey and we are very grateful

for his hospitality and generosity. All other collaborators and stakeholders and in particular the

District forest officer Mr. James Wafula. To all, God bless.

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TABLE OF CONTENTS

Executive summary .............................................................................................................................. 2

Acknowledgements .............................................................................................................................. 4

Table of Contents ................................................................................................................................. 5

List of Figures ....................................................................................................................................... 6

List of Tables ......................................................................................................................................... 6

1.0 INTRODUCTION .............................................................................................................................. 7

1.2 Study objectives ......................................................................................................................... 8

2.0 Methodology .................................................................................................................................. 9

2.1 Data Analysis ............................................................................................................................ 10

3.0 Results ..................................................................................................................................... 12

3.1 Floristic composition ................................................................................................................ 12

3.1.1 Species area curve ............................................................................................................. 14

3.2 Botanical Uniqueness ............................................................................................................... 14

3.3 SPECIES RICHNESS and Diversity .............................................................................................. 15

3.4 Forest structure ........................................................................................................................ 15

3.4.1 Canopy cover ..................................................................................................................... 15

3.4.2 Litter layer ......................................................................................................................... 16

3.4.3 Tree population structure ................................................................................................. 17

3.4.4 Height structure ................................................................................................................ 18

3.5 Threats to Kibauni Hill Forest ................................................................................................... 19

4.0 Discussion ..................................................................................................................................... 21

5.0 Conclusions and Recommendations ............................................................................................ 23

References.......................................................................................................................................... 24

Appendices ......................................................................................................................................... 25

Appendix 1: GPS locations of the sampling Plots sampled during dry season sampling within the

five transects in Kibauni Hill Forest ................................................................................................ 25

Appendix 2 Plant Checklist of Kibauni Hill Forest .......................................................................... 26

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LIST OF FIGURES

Figure 1: Map of Kibauni Hill Forest showing the locality of the five transects and the sampling

zones .................................................................................................................................................. 10

Figure 2: Percentage family representation ...................................................................................... 12

Figure 3: Life form spectrum of Kibauni plants during in the dry and wet season ........................... 13

Figure 4: Species-area curve used to assess sample adequacy ......................................................... 14

Figure 5: Mean Percentage cover per transect ................................................................................. 16

Figure 6: Mean percentage litter and soil/bare rock cover ............................................................... 17

Figure 7: Tree Stem size class distribution (> 5 cm DBH) in the five transects .................................. 18

Figure 8: Tree Stem size class distribution (> 5 cm DBH) in the five transects .................................. 18

Figure 9: Mean tree height per transect ............................................................................................ 19

Figure 10: Mean number of tracks recorded per transect ................................................................ 19

Figure 11: Mean number of tree stumps recorded per transect ...................................................... 20

LIST OF TABLES

Table 1: Rare and Endemics plant species of Kibauni Hill Forest ....................................................... 14

Table 2: Species richness, diversity and evenness within the five transects ..................................... 15

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1.0 INTRODUCTION

For decades, Kenyan forests have been subject to high levels of deforestation, fragmentation and

degradation. Increasing population densities and land use pressures such as legal and illegal

logging, extensive cattle grazing, forest fires and cultivation are responsible for much of tropical

deforestation. Traditionally, people have exploited natural resources for socio-economic benefits.

However, unsustainable exploitation of self-regulating ecosystems leads to gradual loss of services

it provides resulting in changes in biodiversity composition, structure and numbers. For instance,

agriculture expansion into forestland triggers natural habitat destruction, faunal and floral species

decline, interference of nesting and breeding grounds of birds and thereby deteriorating the

services that people are depended upon. To prevent further extensive forest degradation and to

restore already damaged forest area, there is a need for conservation, intensive forest

management and monitoring of potential effects of deforestation. To achieve these goals requires

site-specific, fine-scale data and an understanding of the trends, magnitude and rates of

ecosystem change following deforestation.

The decline of forest cover in developing countries and particularly in Africa is alarming, with

approximately 4 million ha of forest being lost annually. Undoubtedly, Kibauni Hill forest adds up

to this statistic. Overexploitation of forest resources by the populous and generally poor

community is the key threat to this ecosystem. Proper management is therefore necessary, so as

to curb the imminent dangers of human destruction and maintain its conservation.

Kibauni Hill Forest is a gazetted dryland forest occurring in Yathui division, Machakos District,

Eastern Kenya. It is a dry land forest with an altitudinal range between 1200m and 1650 m a.s.l. It

is managed by the Machakos County Council though negotiations are underway to revert its

management to the Kenya Forest Service. Kibauni Hill consists of peaks of clustered hills of

volcanic nature next to the greater Mbooni hills spreading in an area of about 2000 ha. Kibauni Hill

Forest, like many other forests is also very important in provision of forest carrier functions

(human settlements, support profitable crop production, floral and faunal habitats), forest

service’s forest products (timber materials, wood fuel, herbal medicine, and genetic resources)

and forest nature functions (form major moisture reservoirs, water catchment areas, regulate

river flow, reduce river sediment load, carbon sequestration or sinks, climatic stability, ground

water recharge, erosion and flood control, nutrient conservation and recycling) among others.

Despite its importance and gazettement status, the hill has over the years experienced massive

degradation as a result of human activities. The hill forest is under great pressure from human

activities such as illegal logging, vegetation degradation, extensive agricultural activities right

inside the forest, human settlement in the hills and high levels of poverty and soil erosion

including extensive gully erosion. Failed or weak Government policies regarding county forests and

the inability to enforce the law and protect the forests, have contributed to the high degradation.

All these threats synergise to leave the integrity of the entire ecosystem at risk. To reverse this

trend requires proper understanding of the ecosystem and involvement of the local communities

in its management and conservation. However, there is lack of comprehensive and up to date

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information on the vegetation status of Kibauni Hill forest. This has posed a challenge to planners,

managers and decision-makers regarding the development of management plans, implementation

of strategic plans as well as fostering a monitoring and evaluation programme for the forest. The

Green Resources Initiative, a local NGO has initiated several restoration projects in the forest

however, lack of botanical information is a hindrance to realizing their goal. It has been a

challenge selecting the priority indigenous tree species for the restoration program. It is against

this background that a comprehensive study aimed at assessing floristic composition, structure,

distribution and conservation status of Kibauni Hill forest plants was undertaken.

1.2 STUDY OBJECTIVES

The broad objective of the study was to conduct a botanical inventory of the forest and build

baseline data on the floristic composition, structure, distribution and establish the conservation

status of the forest species to enhance conservation efforts.

The specific objectives were to:

i. Carry out an inventory of representative plant biodiversity in the Kibauni Hill Forest and

describe the plant distribution, composition and abundance in the different forest habitat

types.

ii. Identify plant species of conservation concern e.g. rare and threatened

iii. Identify existing threats to plant biodiversity in the area;

iv. Assess the conservation status of the forest

v. Develop low cost biodiversity monitoring system and recommend management actions

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2.0 METHODOLOGY

Vegetation sampling was done along five transects during both dry (08th October -11th October

2011) and wet (14th December - 17th December 2011) seasons. The transects were spanning from

the forest edge to the hilltop and along an altitudinal gradient (Figure 1). The transects varied in

topography and slope orientation i.e. windward and leeward. Transects T1, T2, and T3 were set on

the leeward side while T4 and T5 were set on the windward side of the hill. Sampling zones were

established along each transect. All sampling zones were geo-referenced using a hand-held GPS to

enable manipulation in a GIS environment and for future monitoring (Appendix 1). Within each

sampling zone, triplicate plots of 20 by 20 m were sampled. The plots were located > 200 m apart

to ensure sample independence. A total of 24 plots were demarcated; 6 plots in transect 1 (T1), 7

plots in transect 2 (T2), 5 plots in transect 3 (T3) and 3 plots each in transects 4 (T4) and 5 (T5).

In each plot, the plants - trees, shrubs and herbs were recorded in order to provide an overview of

plant diversity, composition and structure. Plant species diversity was enhanced by recording

species which were not found in the established plots. Plant specimens were collected, pressed,

dried and deposited at the East African Herbarium. Plant specimens that could not be identified in

the field were confirmed at the East African Herbarium. Plant nomenclature follows Agnew and

Agnew (1994), Beentje (1994) and Flora of Tropical East Africa. The canopy cover and height

within the three life form layers i.e. herb, shrub and tree layers were estimated in each plot. The

forest canopy was estimated from these layers as follows: herbs, less than 1 meter tall, shrubs

between 1 and 5 meters tall and trees, above 5 meters tall. The canopy cover estimation involved

an imaginary projection of the aerial shadow of each vegetation layer on the ground and

estimation of its percentage area. The total percentage cover of each layer was assumed to be

100%. Diameter at breast height (DBH) was measured for all trees with heights exceeding 5 meters

so as to assess the trees population structure. The DBH was measured using a diameter tape

measure. Threats facing Kibauni forest were assessed by quantifying the indicators of disturbance

such as number of stumps, grazing intensity and evidence, wood harvesting, honey collection,

footpaths and charcoal kilns in each plot.

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Figure 1: Map of Kibauni Hill Forest showing the locality of the five transects and the sampling

zones

2.1 DATA ANALYSIS

The floristic diversity was analyzed using data on species richness (i.e. total number of species

recorded per site) and comparison of floristic similarity between study sites and vegetation types

using Srensen Similarity Coefficient/Index. The index assists to compare different habitats or

sites floristically to determine whether their species composition is related or different. The

principal analysis was carried out using PRIMER analytical software version 5 to evaluate the

following aspects of the structure and floristic composition;

Similarity

o Ordination using non- metric multidimensional scaling (MDS) to show dispersion of

sampling sites and plots based on their species similarity

Plant species richness, diversity and evenness

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Shannon- Wiener (H') diversity index were computed and compared for each site and plot.

The Shannon-Wiener diversity index was calculated from the equation:

H' = pilnpi

Where: pi is the proportion of individuals found in the ith species

ln is the natural logarithm

Evenness (J) is the ratio of observed diversity to maximum diversity and is calculated from

the equation: J = H'/ Hmax = H'/lnS

Species area curve

The species-area curve was used to evaluate the adequacy of the sample size used for this

survey.

Structure

Tree species population structure

The population structure of the tree species was summarized using histograms of diameter

size classes.

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3.0 RESULTS

3.1 FLORISTIC COMPOSITION

Overall, a total number of 155 plant species where recorded during the 2 seasons belonging to 48

families and 117 genera (Appendix 1). A higher number of plants species were recorded during the

wet season compared to the dry season (79 species). The most dominant families in the dry

season were: Leguminosae, Euphorbiaceae, Labiatae, Burseraceae, and Anacardiaceae while in the

wet season were; Leguminosae,Euphorbiaceae, Compositae and Graminae (Figure 2).

Figure 2: Percentage family representation

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Life form

Trees were the most dominant life form occupying over 41% of entire area during the dry season

while herbs (39%) were most dominant in the wet season (Figure 3). During the dry season, the

ground cover was bare with most of the herbs having been scorched by the sun. Open ground

cover and shrub layer amid the scantily leaved trees characterized the dry season. The wet season

had a thick undergrowth and closed shrub and tree layers (Plate 1). There was no significant

change in distribution of shrub and climbers within the two seasons.

Figure 3: Life form spectrum of Kibauni plants during in the dry and wet season

Plate 1: Shrub layer and tree canopy during the wet season

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3.1.1 Species area curve

A plot of the species -area curve showed that over 50% of all the species were recorded in the first

6 plots with more plots yielding relatively small increases in the number of species (Figure 4). The

species area curve did not reach an asymptote indicating that the 24 plots did not adequately

sample all the species of Kibauni Hill forest and more species could be recorded with additional

sampling.

Figure 4: Species-area curve used to assess sample adequacy

3.2 BOTANICAL UNIQUENESS

Five species were found to be of conservation concern based on the IUCN Red Plant list (IUCN,

1997). The five species were found to be Kenyan endemics and two of them are rated as rare or

vulnerable (Table 1).

Table 1: Rare and Endemics plant species of Kibauni Hill Forest

Family Species L/F Conservation Status

(IUCN 1997 red list) Endemism Source

Euphorbiaceae Bridelia taitensis Vatke & Pax T Endemic National EA, FTEA, 1987; KTSL

Euphorbiaceae Synadenium compactum N.E.Br. T Rare, Endemic National EA; IUCN 1997, UFT (VOL 1 NO 3) 1988;FTEA 1988, KTSL

Leguminosae Acacia elatior Brenan T Endemic National FTEA, 1959; KTSL

Leguminosae Millettia leucantha Vatke T Endemic, Rare /Vulnerable

National FTEA, 1971

Vitaceae Cissus quadrangularis L. C Endemic National EA; FTEA, 1993

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3.3 SPECIES RICHNESS AND DIVERSITY

There was a significant increase in species richness and diversity during the wet season, in each

transect. In the dry seasons, species richness and diversity was highest in Transect 2 (T2) while

Transect 1 (T1) was the most diverse in the wet season. The least diverse transect in both seasons

was Transect 5 (T5) (Table 3).

Table 2: Species richness, diversity and evenness within the five transects

Species richness, diversity & evenness in the dry season

T1 T2 T3 T4 T5

Number of individuals (N) 106 173 98 48 53

Species richness (S) 44 52 34 22 20

Species Diversity (H'(loge)

)

3.54 3.60 3.10 2.83 2.49

Species Evenness (J') 0.94 0.91 0.88 0.91 0.83

Species richness, diversity & evenness in the wet season

T1 T2 T3 T4 T5

Number of individuals (N) 228 285 141 104 104

Species richness (S) 96 98 65 57 54

Species Diversity (H'(loge)

)

4.36 4.27 3.8 3.87 3.64

Species Evenness (J') 0.95 0.93 0.91 0.96 0.91

3.4 FOREST STRUCTURE

3.4.1 Canopy cover

A general look at the canopy structure across all transects in both seasons showed a low

representation of tree layer. The shrub layer was the dominant strata in all the transects except in

transect 4 (T4) where the herb layer was the most dominant (Figure 5). Transects 4 and 5 were

more open with the least percentage cover of tree and shrub layer. Transect 2 had a relative high

tree cover compared to the other transects. There was a marked increase of herbs in all transects

during the wet season and more notably in Transect 1 and Transect 3. Generally, Kibauni Hill

forest has scattered trees and a dense shrub layer.

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DRY SEASON

WET SEASON

Figure 5: Mean Percentage cover per transect

3.4.2 Litter layer

In the dry season, the ground cover of most of the transects was bare soil and rock with very little

litter cover (Figure 6). However, in the wet season, most of the bare area was covered by herbs.

High percentages of litter cover was recorded in transects 2 (T2) and 3 (T3) in both seasons. There

was a remarkable decrease in the amount of litter in the wet season in all transects.

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DRY SEASON

WET SEASON

Figure 6: Mean percentage litter and soil/bare rock cover

3.4.3 Tree population structure

The stem size class distribution of trees with DBH more than 5 cm in the five transects is shown in

Figure 7. Majority of trees were in the lower DBH classes of below 20 cm. In transect T2 and T3,

the distribution was inverse j-shaped with a high proportion of individuals in the lowest class, a

gradual decline in the next classes. The stem distribution in T1, T4 and T5 did not depict a distinct

J-shape with individuals missing in some stem classes. A comparison of stem size distribution

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between trees on the windward and leeward side showed that the distribution on the leeward

side was inverse j-shaped but the windward side did not have a distinct j-shape (Figure 8).

Figure 7: Tree Stem size class distribution (> 5 cm DBH) in the five transects

Figure 8: Tree Stem size class distribution (> 5 cm DBH) in the five transects

3.4.4 Height structure

Overall, the average height of Kibauni hill forest trees is 8.4 m. Transect 1 (T1) had the tallest trees

with a mean height of about 9m while Transect 2 (T2) had the shortest trees (Figure 9).

Transect T1,T2,T3- Leeward

Transect T4 & T5- Windward

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Figure 9: Mean tree height per transect

3.5 THREATS TO KIBAUNI HILL FOREST

A number of threats facing Kibauni Hills plants were observed. This included cattle grazing, tree

poaching, firewood collection, charcoal burning, debarking of herbal plants and soil erosion. There

were more tracks and tree stumps on Transect T4 and T5 which occur on the windward side of the

hill (Figure 10 & 11). During the dry season, grazing intensity was high in all the transects as

evidenced by presence of cattle, bitten off plants, excrements and animal tracks. Other signs of

disturbance included charcoal kilns which were only noted in Transect 2. However, there was a

significant reduction in grazing intensity and wood harvesting during the wet season. A lot of

vegetation clearing was observed to pave way for settlement and agricultural activities. Removal

of vegetation has led to loosening of the soil which is washed away during the rainy season leading

to soil erosion and gully formation.

Figure 10: Mean number of tracks recorded per transect

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Figure 11: Mean number of tree stumps recorded per transect

Some threats facing Kibauni Hill Forest

Cattle grazing

Firewood collection

Debarking of trees

Charcoal burning

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4.0 DISCUSSION

A total of 155 plant species including five endemic plants species, one rare and one vulnerable

were recorded along five transects within the two sampling seasons. The presence of species of

special concern i.e. rare, endemic and vulnerable increases the need to conserve Kibauni Hill

Forest. The species area curve did not reach asymptote indicating that the 24 plots did not capture

most of the Kibauni Hill plants. As expected more herbs were recorded during the wet season

which contributed to a higher number of plant species during the wet season (155) compared to

the dry season (79 species). This indicates the importance of sampling in different seasons.

The Central transect (T2) which ascends to the highest point of the forest was the most diverse in

the dry season while transect 1 (T1), was most diverse in the wet season. The high diversity of T1

during the rainy season can be attributed to its more open canopy compared to T2, which allowed

growth of herbs. Transect 5 (T5) on the windward side had the least species richness and diversity

in both seasons. Surprisingly, the transects on the leeward side of the hill were more diverse than

on one on the leeward side. This is due to heavy human disturbance on the windward side of the

hill as evidenced by the human disturbance indicators. Most of the trees on the windward side

have been poached by the adjacent local communities.

Kibauni Hill forest is a low stature forest as depicted by the mean tree height. The dominance of

herb and shrub layer in Kibauni Hill indicates that the forest is open and could be as a result of

Tree poaching Tree poaching

Gullies due to soil erosion Gullies due to soil erosion

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disturbance. The tree layer makes up only 30% of the forest resulting to proliferation of the

herbaceous and shrub species. In the dry season, the lowest occurrence of shrubs (an average of

10%) was recorded in transect 4 while the highest (an average of 70%) was recorded in transect 1.

Transects 4 and 5 which occurred in the highly degraded windward side had lower representation

by shrub and tree layers compared to the other transects. This scenario of open upper canopy in

these transects explain the higher composition by herbs. It is also an indication of interference by

human activities. The highest cover by tree layer was recorded in transect 2 which cuts through

the centre of the forest and has the highest altitude. The high tree dominance can be attributed to

its location whose inaccessibility deters poachers. In addition, past restoration attempts where

tree cover was boosted with introduction of Croton megalocarpus and Eucalyptus saligna trees

contribute to the high tree cover.

Tree regeneration patterns are normally identified by structural analyses (age, size) of populations

(Taylor & Zinsheng, 1988). The recognition of pattern may enhance our understanding of the

relationship between forest structure, composition, diversity and disturbance regimes. The tree

stem size distribution in transects T2 and T3 depicted an inverse-J shape indicating that sufficient

regeneration is taking place and the tree populations are viable and stable. However in transects

T1, T4 and T5 the distribution did not depict a distinct inverse J-shape indicating a less unstable

population structure. The low proportion of individuals in all the DBH classes indicates that these

sites suffered severe disturbance in the past either through logging where most of the mature tree

species where removed. The high proportion of individuals in transect 2 (T2) for the lower classes

is an indication that the severe disturbances have ceased and that this forest site is in a state of

recovery. The tree stem size distribution in windward side of the hill depicted an unstable

population structure due to the high human disturbance levels compared to the leeward side.

The plant diversity in Kibauni Hill forest is at risk from a myriad of threats which include cattle

grazing, illegal poaching of certain high value tree species, human encroachment, charcoal

burning, firewood collection and soil erosion. Removal of vegetation over the years has led to soil

erosion which has consequently led to formation of deep gullies. Most of the high value trees have

been logged opening up the tree canopy and leading to proliferation of shrubs and herbs. It is clear

that habitat modification and deforestation have had some effect of species composition and

forest structure. There is likelihood of local extirpation of some species especially the high valued

tree species. For instance, Kibauni forest is named after Dombeya kirkii which used to be dominant

in the forest. However, to date only a few individuals of this species can be spotted.

Clearing of vegetation has reduced the capacity of the forest to store water and withstand

overflows during the rainy season. This has adversely affected water quality and quantity in rivers

and streams that flow from the forest and drain to the Athi River. Some rivers which used to be

permanent have become seasonal rivers.

Kibauni Hill is surrounded by high human population and most are poor forcing them to depend

heavily on the natural resources of Kibauni Hill. Some people have migrated to the hilltops in

search of more productive agricultural land especially on the windward side of the forest. The

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forest has hence become fragmented over time. Unclear forest boundary has contributed to

encroachment by the forest adjacent communities.

5.0 CONCLUSIONS AND RECOMMENDATIONS

In conclusion, Kibauni Hill forest is a dry forest with low stature and open canopy. The forest

serves as refugium of plant diversity however, it is highly threatened by anthropogenic

interference especially on the windward side of the forest. The survival of the plant diversity is

therefore at risk and the following recommendations are proposed to safeguard it:

8. There is need to create awareness and educate the local communities on the importance

of the forest and the need to conserve the forest.

9. Though the extent and magnitude of identified threats was not measured, there is need to

control the on-going illegal activities through strict policing and surveillance.

10. Alternative means of livelihoods e.g. bee keeping, should be promoted to reduce over

dependence on the forest resources.

11. A participatory management plan for Kibauni Hill forest should be developed and

implemented involving all the stakeholders.

12. Forest restoration efforts involving the forest adjacent communities should be enhanced

especially on the windward side of the hill which is highly degraded.

13. There is need to boost conservation efforts especially for the four endemic plant species

including two rare or one vulnerable species recorded.

14. The sampled plots should be monitored on a regular basis to inform managers on the

forest status. All the plots sampled were georeferenced (Appendix 1) and can be used as

Permanent Sample Plots (PSPs) for monitoring purposes in order to establish any trends in

species, occurrence, distribution or abundance in time, especially in the face of climate

change and any other (human-driven) disturbances.

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REFERENCES

Agnew A.D.Q. & Agnew S. (2nd Ed.) 1994. Upland Kenya Wild Flowers: A flora of the ferns and

herbaceous flowering plants of upland Kenya. East African Natural History Society, Nairobi.

Beentje H.J., 1994. Kenya, Trees, Shrubs and Lianas. National Museums of Kenya.Nairobi.

IUCN, (2007). Redlist of Threatened Species. www.iucnredlist.org. Downloaded

Taylor A. H. & Zinsheng Q., 1988. Regeneration patterns in old-growth Abies-Betula forests in the

Wolong Natural Reserve, Sichuan, China. J. Ecology 76: 1204-1218

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APPENDICES

APPENDIX 1: GPS LOCATIONS OF THE SAMPLING PLOTS SAMPLED DURING DRY SEASON

SAMPLING WITHIN THE FIVE TRANSECTS IN KIBAUNI HILL FOREST

Transect Sampling Plot Co-ordinates

1 1 S1 32.795 E37 37.950

1 2 S1 32.754 E37 37.995

1 3 S1 32.700 E37 38.062

1 4 S1 32.675 E37 38.126

1 5 S1 32.661 E37 38.205

1 6 S1 32.624 E37 38.261

2 7 S1 33.038 E37 38.163

2 8 S1 33.006 E37 38.214

2 9 S1 32.970 E37 38.272

2 10 S1 32.932 E37 38.323

2 11 S1 32.916 E37 38.381

2 12 S1 32.875 E37 38.439

3 13 S1 32.909 E37 38.633

3 14 S1 33.007 E37 38.670

3 15 S1 33.063 E37 38.630

3 16 S1 33.102 E37 38.589

3 17 S1 33.159 E37 38.523

3 18 S1 33.220 E37 38.446

4 19 S1 32.538 E37 38.622

4 20 S1 32.617 E37 38.599

4 21 S1 32.711 E37 38.591

5 22 S1 32.813 E37 38.682

5 23 S1 32.726 E37 38.801

5 24 S1 32.585 E37 38.821

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APPENDIX 2 PLANT CHECKLIST OF KIBAUNI HILL FOREST

Family Species Life form

Acanthaceae Crabbea velutina S.Moore H

Acanthaceae Justicia calyculata Deflers H

Acanthaceae Justicia flava Vahl H

Acanthaceae Justicia sp H

Actiniopteridaceae Actiniopteris dimorpha Pic.Serm. H

Aloaceae Aloe secundiflora Engl. H

Amaranthaceae Achyranthes aspera L. H

Amaranthaceae Amaranthus graecizans L. H

Amaranthaceae Celosia anthelminthica Asch. H

Amaryllidaceae Crinum macowanii Baker H

Anacardiaceae Lannea schweinfurthii (Engl.) Engl. T

Anacardiaceae Rhus natalensis Krauss T

Anacardiaceae Rhus vulgaris Meikle T

Anacardiaceae Sclerocarya birrea (A.Rich.) Hochst. T

Annonaceae Uvaria scheffleri Diels S

Anthericaceae Chlorophytum sp H

Apocynaceae Adenium obesum (Forssk.) Roem. & Schult. S

Asclepiadaceae Secamone parvifolia (Oliv.) Bullock C

Asparagaceae Asparagus africanus Lam. S

Asparagaceae Asparagus flagellaris (Kunth) Baker H

Asparagaceae Asparagus racemosus Willd. H

Asparagaceae Asparagus setaceus (Kunth) Jessop H

Boraginaceae Cordia monoica Roxb. T

Burseraceae Commiphora baluensis Engl. T

Burseraceae Commiphora campestris Engl. T

Burseraceae Commiphora habessinica (O.Berg) Engl. T

Burseraceae Commiphora mildbraedii Engl. T

Capparaceae Capparis tomentosa Lam. S

Capparaceae Cleome monophylla L. H

Capparaceae Maerua kirkii (Oliv.) F.White T

Capparaceae Maerua triphylla A.Rich. S

Celastraceae Maytenus heterophylla (Eckl. & Zeyh.) N.Robson T

Combretaceae Combretum aculeatum Vent. S

Combretaceae Terminalia brownii Fresen. T

Commelinaceae Commelina africana L. H

Commelinaceae Commelina benghalensis Wall. H

Compositae Acanthospermum hispidum DC. H

Compositae Aspilia mossambicensis (Oliv.) Wild H

Compositae Bidens biternata (Lour.) Merr. & Sherff H

Compositae Bidens pilosa L. H

Compositae Bidens ternata (Chiov.) Sherff H

Compositae Bothriocline fusca (S.Moore) M.G.Gilbert S

Compositae Emilia discifolia (Oliv.) C.Jeffrey H

Compositae Galinsoga parviflora Cav. H

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Compositae Gutenbergia boranensis (S.Moore) M.G.Gilbert H

Compositae Helichrysum glumaceum DC. S

Compositae Hirpicium diffusum (O.Hoffm.) Roessler H

Compositae Tagetes minuta L. H

Compositae Vernonia anthelmintica (L.) Willd. H

Convolvulaceae Evolvulus alsinoides (L.) L. H

Convolvulaceae Ipomoea kituensis Vatke S

Convolvulaceae Ipomoea plebeia R.Br. C

Convolvulaceae Turbina stenosiphon (Hallier f.) A.Meeuse C

Crassulaceae Kalanchoe densiflora Rolfe H

Cyperaceae Kyllinga sp H

Ebenaceae Euclea divinorum Hiern T

Euphorbiaceae Acalypha fruticosa Forssk. S

Euphorbiaceae Bridelia micrantha (Hochst.) Baill. S

Euphorbiaceae Bridelia taitensis Vatke & Pax T

Euphorbiaceae Croton dichogamus Pax S

Euphorbiaceae Croton megalocarpus Hutch. T

Euphorbiaceae Drypetes gerrardii Hutch. T

Euphorbiaceae Euphorbia bussei Pax var. kibwezensis (N.E.Br.)S.Carter T

Euphorbiaceae Euphorbia candelabrum Kotschy T

Euphorbiaceae Euphorbia hirta L. T

Euphorbiaceae Flueggea virosa (Willd.) Voigt S

Euphorbiaceae Phyllanthus fischeri Pax S

Euphorbiaceae Phyllanthus odontadenius Müll.Arg. H

Euphorbiaceae Ricinus communis L. S

Euphorbiaceae Synadenium compactum N.E.Br. T

Euphorbiaceae Tragia brevipes Pax H

Gramineae Aristida adoensis Hochst. H

Gramineae Bothriochloa insculpta (A.Rich.) A.Camus H

Gramineae Brachiaria sp H

Gramineae Cynodon sp H

Gramineae Digitaria sp H

Gramineae Digitaria velutina (Forssk.) P.Beauv. H

Gramineae Enteropogon monostachyos (Vahl) K.Schum. H

Gramineae Harpachne schimperi A.Rich. H

Gramineae Panicum maximum Jacq. H

Gramineae Rhynchelytrum repens (Willd.) C.E.Hubb. H

Gramineae Setaria pumila (Poir.) Roem. & Schult. H

Gramineae Sporobolus sp H

Gramineae Tragus sp H

Labiatae Hoslundia opposita Vahl S

Labiatae Leucas glabrata (Vahl) R.Br. H

Labiatae Leucas grandis Vatke S

Labiatae Ocimum americanum L. S

Labiatae Ocimum gratissimum Forssk. H

Labiatae Plectranthus sp H

Labiatae Tinnea aethiopica Kotschy ex Hook.f. S

Leguminosae Acacia brevispica Harms T

Leguminosae Acacia elatior Brenan T

Leguminosae Acacia mellifera (Vahl) Benth. T

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Leguminosae Acacia nilotica (L.) Willd. ex Delile T

Leguminosae Acacia seyal Delile T

Leguminosae Acacia tortilis (Forssk.) Hayne T

Leguminosae Albizia anthelmintica Brongn. T

Leguminosae Crotalaria goodiiformis Vatke S

Leguminosae Dolichos sericeus E.Mey. C

Leguminosae Entada leptostachya Harms S

Leguminosae Erythrina abyssinica DC. T

Leguminosae Indigofera arrecta A.Rich. H

Leguminosae Indigofera lupatana Bak.f. S

Leguminosae Indigofera volkensii Taub. H

Leguminosae Lonchocarpus bussei Harms T

Leguminosae Millettia leucantha Vatke T

Leguminosae Senna singueana (Delile) Lock T

Leguminosae Stylosanthes fruticosa (Retz.) Alston S

Leguminosae Tephrosia sp H

Malpighiaceae Caucanthus auriculatus (Radlk.) Nied. C

Malvaceae Hibiscus fuscus Garcke S

Malvaceae Hibiscus micranthus L.f. S

Malvaceae Hibiscus sp S

Malvaceae Pavonia patens (Andr.) Chiov. S

Malvaceae Pavonia zeylanica Cav. H

Malvaceae Sida acuta H

Meliaceae Turraea mombassana C.DC. S

Menispermaceae Cissampelos pareira L. C

Myrsinaceae Maesa lanceolata Forssk. S

Ochnaceae Ochna inermis (Forssk.) Schweinf. T

Ochnaceae Ochna ovata O.Hoffm. T

Oleaceae Jasminum fluminense Vell. C

Opiliaceae Opilia amentaceae S

Oxalidaceae Biophytum abyssinicum A.Rich. H

Polygalaceae Polygala sphenoptera Fresen. H

Polygonaceae Oxygonum sinuatum (Meisn.) Dammer H

Rhamnaceae Scutia myrtina (Burm.f.) Kurz S

Rubiaceae Hymenodictyon parvifolium Oliv. S

Rubiaceae Otomeria oculata S.Moore H

Rubiaceae Pavetta gardeniifolia A.Rich. S

Rubiaceae Pentas parvifolia Hiern S

Rubiaceae Psychotria kirkii Hiern S

Rubiaceae Rytigynia sp T

Rubiaceae Vangueria madagascariensis J.F.Gmel. T

Rutaceae Clausena anisata (Willd.) Benth. S

Rutaceae Vepris glomerata (F.Hoffm.) Engl. S

Sapindaceae Allophylus rubifolius (Hochst.) Engl. T

Sapotaceae Manilkara discolor (Sond.) J.H.Hemsl. T

Solanaceae Solanum hastifolium Hochst. ex Dun. C

Solanaceae Solanum incanum L. S

Solanaceae Solanum terminale Forssk. C

Sterculiaceae Dombeya kirkii Mast. T

Sterculiaceae Hermannia uhligii Engl. S

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Sterculiaceae Melhania velutina Forssk. H

Thymelaeaceae Gnidia latifolia (Oliv.) Gilg S

Tiliaceae Grewia bicolor Juss. T

Tiliaceae Grewia similis K.Schum. S

Tiliaceae Triumfetta annua L. H

Urticaceae Obetia radula (Baker) B.D.Jacks. T

Verbenaceae Vitex strickeri Vatke & Hildebrandt C

Vitaceae Cissus quadrangularis L. C

Vitaceae Cissus rotundifolia (Forssk.) Vahl C

Vitaceae Cyphostemma adenocarpum (Gilg & Brandt) Desc. C

Vitaceae Cyphostemma maranguense (Gilg) Desc. C

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