Bale Mountains National Park is one of the protected areas in Ethiopia that holds the largest area of Afroalpine habitat in Africa and the second largest stand of moist tropical forest. Nevertheless, human settlements, overgrazing, and recurrent fire are the main problems in the park. This study aimed to determine the effects of human-induced landscape change in floristic composition and structure in the park. The vegetation data were collected systematically from 96 sample plots laid along 24 line transects in the edge and interior habitats of the six land cover types. Vegetation composition and landscape structural analysis were made using
Landscapes all over the world are alarmingly changed and fragmented due to anthropogenic factors such as urbanization, agricultural expansion, forest fire, and climate change [
Tropical montane ecosystem is one of the hot spot ecosystems on Earth that comprises more than 200,000 species of flowering plants [
The mountainous landscape and the mosaic of natural vegetation in the Bale Mountains have considerable economic, recreational, esthetic, and scientific importance [
BMNP is located within the geographic bounds of 6°53′08″N latitude and 39°44′03″E longitude and 400 km southeast of Addis Ababa, Ethiopia (Figure
Location map of the study area.
From 13 to 20 November 2018, a reconnaissance survey was conducted to get insights into the vegetation physiognomy and establish sampling sites in the study area. Following, the actual fieldwork was performed in the dry season between November 2019 and January 2020. A total of 96 sample plots (20 × 20 m) were systematically laid along 24 line transects in eight directions along three altitudinal gradients at 100 m elevational differences as it maximizes the distance between plots and minimizes spatial correlation among the observations [
Plant species in the nested plots were identified at the field with the help of local peoples (for vernacular names) and by referring different volumes of Flora of Ethiopia and Eritrea books [
The most commonly used diversity indices of species richness (
The Margalef diversity index (
The woody species density, frequency, dominance, and their relative values in the interior and edge habitats were computed to obtain the important value index and describe the woody species structure following Ellenberg and Mueller-Dombois [
Landsat images of the years 1985, 1995, 2005, and 2017 were processed using ArcGIS version 10.3 to produce time-series datasets of land use/land cover. Then, eight landscape indices were analyzed using the processed land use/land cover data following McGarigal et al. [
The analysis of landscape structure in this study revealed that the habitats in the BMNP are progressively transformed. The area has shown an increase in PN by 40.2% and a decrease in AREA_MN by 28.7% from 1985 to 2017. According to Oertli et al. [
The isolation of patches within the landscape of the study area was increased from 105.22 m to 111.94 m overtime (Table
Landscape structural characteristic of the BMNP from 1985 to 2017.
Year | NP | AREA_MN (ha) | SHAPE_AM | TCA (km2) | ED (m/m2) | ENN_MN (m) | IJI (%) |
---|---|---|---|---|---|---|---|
1985 | 25864 | 8.42 | 24.97 | 1568.91 | 60.53 | 107.27 | 77.69 |
1995 | 30582 | 7.12 | 24.12 | 1489.10 | 69.18 | 105.22 | 79.29 |
2005 | 29329 | 7.42 | 29.36 | 1471.02 | 66.44 | 111.94 | 70.78 |
2017 | 36267 | 6.00 | 29.67 | 1402.59 | 74.02 | 109.21 | 75.46 |
% | 40.22 | −28.68 | 18.83 | −10.60 | 22.28 | 1.81 | −2.87 |
Note. The negative sign of percentage implies a decreasing trend, and the positive sign implies an increasing trend.
A total of 205 plant species belonging to 71 families and 153 genera were recorded (Table
List of plant species identified in the BMNP.
Scientific name | Family | Local name (Or.) | Habit | Coll. no. |
---|---|---|---|---|
Fabaceae | Wanga | S | AM168 | |
Celastraceae | Karxafa | S | AM172 | |
Amaranthaceae | Roppe, Qorsa Waranssa | H | AM094 | |
Poaceae | Mergeseri | H | AM009 | |
Lamiaceae | — | H | AM078 | |
Mimosaceae | Karchofe | T | AM174 | |
Rosaceae | Hindriff | H | AM043 | |
Rosaceae | Hindriff | H | AM159 | |
Rosaceae | — | H | AM055 | |
Rosaceae | Hindriff, Indriif | H | AM017 | |
Rosaceae | — | H | AM052 | |
Apiaceae | — | H | AM060 | |
Sapindaceae | Abara | T | AM131 | |
Sapindaceae | Sarara | T | AM178 | |
Physciaceae | Lichen | H | AM054 | |
Annonaceae | Gishta | T | AM161 | |
Asteraceae | — | H | AM012 | |
Papaveraceae | Qore Haree | H | AM018 | |
Asteraceae | Tepenea, Tepeno | H | AM007 | |
Asparagaceae | Seriti | S | AM199 | |
Aspleniaceae | Qumbuta | H | AM155 | |
Fabaceae | Hara | E | AM037 | |
Asteraceae | Hade gola | H | AM040 | |
Apocynaceae | Homba | H(clim) | AM122 | |
Orchidaceae | Shumbura gala | H | AM066 | |
Poaceae | Alanmuressa | H | AM106 | |
Fabaceae | Cheekata | S | AM167 | |
Asteraceae | Qore Haree | H | AM107 | |
Asteraceae | Qore Haree | H | AM033 | |
Apocynaceae | Hagamssa(Or), Agam(Amh) | S | AM181 | |
Apocynaceae | Harangma | S | AM200 | |
Rutaceae | Kasmira | T | AM163 | |
Celastraceae | Jimaa | S | AM143 | |
Ulmaceae | Meteqamma | T | AM116 | |
Apiaceae | Balee, Qudu | H | AM064 | |
Caryophyllaceae | Duqusha chuffa | H | AM087 | |
Rutaceae | Lomii | S | AM186 | |
Rutaceae | Burtukana | S | AM187 | |
Ranunculaceae | Fitii | Li | AM114 | |
Rubiaceae | Buuna | S | AM121 | |
Combretaceae | Dhandhaasa | T | AM190 | |
Commelinaceae | Gura Jarsa | H | AM020 | |
Boraginaceae | Wodessa | T | AM160 | |
Scrophulariaceae | — | H | AM102 | |
Asteraceae | Marga Hoffi | H | AM025 | |
Asteraceae | — | H | AM071 | |
Fabaceae | Shashamane | S | AM201 | |
Euphorbiaceae | Makkannisa | T | AM119 | |
Convolvulaceae | Segeniti | H(clim) | AM098 | |
Scrophulariaceae | — | H | AM080 | |
Boraginaceae | Qarccabbaa | H | AM081 | |
Boraginaceae | Qarccabbaa | H | AM026 | |
Boraginaceae | — | H | AM058 | |
Cyperaceae | Alando | H | AM023 | |
Asteraceae | — | H | AM056 | |
Asteraceae | — | H | AM105 | |
Ebenaceae | Lookoo | T | AM153 | |
Ebenaceae | Kolati | T | AM176 | |
Solanaceae | Meraro | S | AM084 | |
Dracaenaceae | Ruukeessa | T | AM194 | |
Asteraceae | Qore Haree | S | AM099 | |
Asteraceae | Tuqa, Qoree | H | AM036 | |
Boraginaceae | Ulaagaa | T | AM135 | |
Celasteraceae | Xilloo | T | AM137 | |
Mimosoideae | Kontir | S | AM075 | |
Ericaceae | Satoo | S/T | AM073 | |
Ericaceae | — | S | AM065 | |
Fabaceae | Waleensu | T | AM175 | |
Ebenaceae | Miheesa | T | AM164 | |
Euphorbiaceae | Guri Xixiqo | H | AM010 | |
Euphorbiaceae | Gurii | S | AM090 | |
Brachytheciaceae | Hasufe (O), Mosses (E) | E | AM044 | |
Asteraceae | — | S | AM051 | |
Rutaceae | Siisaa | T | AM150 | |
Apiaceae | Gnida | H | AM014 | |
Poaceae | — | H | AM062 | |
Moraceae | Qiltu | T | AM169 | |
Sapindaceae | Caanaa | T | AM156 | |
Salicaceae | Hokoku | S | AM180 | |
Rubiaceae | Maxxane | H | AM016 | |
Geraniaceae | Bucha | H | AM068 | |
Geraniaceae | Balee Tiqo | H | AM097 | |
Rhamnaceae | Wayebossaa | H(clim) | AM128 | |
Proteaceae | Grevillea | T | AM170 | |
Asteraceae | Raffu | H | AM101 | |
Orchidaceae | Kerkashaw | H | AM112 | |
Rosaceae | Hexxoo | T | AM082 | |
Asteraceae | — | H | AM113 | |
Scrophulariaceae | — | H | AM104 | |
Scrophulariaceae | — | H | AM032 | |
Asteraceae | — | S | AM042 | |
Asteraceae | — | H | AM011 | |
Asteraceae | — | S | AM063 | |
Asteraceae | — | H | AM024 | |
Asteraceae | — | H | AM006 | |
Asteraceae | Ufea/Hoffii | H | AM039 | |
Asteraceae | Agadena | H | AM095 | |
Asteraceae | Badubera | H | AM048 | |
Asteraceae | Badubera | S | AM001 | |
Malvaceae | Hincinni | H | AM146 | |
Celasteraceae | Gaguro | H(clim) | AM145 | |
Celasteraceae | Gaalee Gaguro | H(clim) | AM152 | |
Celasteraceae | Xara'a | H(clim) | AM147 | |
Apiaceae | — | H | AM072 | |
Hypericaceae | H | AM035 | ||
Hypericaceae | Geremba | T/S | AM002 | |
Hypericaceae | — | H | AM031 | |
Asteraceae | Haxxawii | S | AM197 | |
Oleaceae | Dikii | H(clim) | AM123 | |
Cupressaceae | Hindessa | T | AM083 | |
Crassulaceae | — | S | AM103 | |
Asphodelaceae | Lela | H | AM008 | |
Asphodelaceae | Lela Xixiqo | H | AM027 | |
Asphodelaceae | Lela Xixiqo | H | AM013 | |
Apocynaceae | Homba | H(clim) | AM151 | |
Anacardiaceae | Andarku | S | AM185 | |
Lamiaceae | Bokolu | S | AM202 | |
Meliaceae | Saakarro | T | AM148 | |
Mimosoideae | Lucinaa | S | AM189 | |
Lobeliaceae | Taruurra(O), Jibra(Am) | S | AM041 | |
Euphorbiaceae | Argoo | T | AM140 | |
Malvaceae | Lita | S | AM029 | |
Anacardiaceae | Mango | T | AM162 | |
Phyllanthaceae | Bulala | T | AM141 | |
Celastraceae | Kombolcha | T | AM173 | |
Celastraceae | Kombolcha, Duqusha (Or.) | S | AM091 | |
Celastraceae | Kombolcha | S | AM100 | |
Meliaceae | Kinin zaf | T | AM191 | |
Sapotaceae | Qolati | T | AM120 | |
Iridaceae | Loga | S | AM115 | |
Myrsinaceae | Qachamo | S | AM203 | |
Myrsinaceae | Tuullaa | T | AM074 | |
Lamiaceae | — | S | AM003 | |
Lauraceae | Gigicha | T | AM118 | |
Rubiaceae | Omachessaa | H | AM028 | |
Oleaceae | Gagama | T | AM132 | |
Oleaceae | Ejerssaa | T | AM157 | |
Oleaceae | Onomaa | T | AM134 | |
Santalaceae | Waatoo | S | AM183 | |
Santalaceae | Karo | S | AM198 | |
Poaceae | — | H | AM061 | |
Phytolaccaceae | Handode | H(clim) | AM205 | |
Fabaceae | Lilluu | T | AM165 | |
Plantaginaceae | Qinxaa, Baallee | H | AM045 | |
Podocarpaceae | Birbirssaa | T | AM130 | |
Poaceae | Daaffa | H | AM144 | |
Polygalaceae | Grisa/Garasita | H | AM005 | |
Araliaceae | Kooribaa | T | AM139 | |
Dryopteridaceae | Qumbuta, Gammanyee | H | AM069 | |
Sapotaceae | Guduba | T | AM138 | |
Asteraceae | — | H | AM070 | |
Myrtaceae | Zeytuna | S | AM177 | |
Rubiaceae | Ulaagaa | S | AM154 | |
Rubiaceae | Galle | T | AM149 | |
Pteridaceae | Qumbuta | H | AM126 | |
Ranunculaceae | Sherif | H | AM077 | |
Myrsinaceae | Tulla | T | AM196 | |
Anacardiaceae | Dabaqaa | S | AM171 | |
Euphorbiaceae | Koboo, Gulo | S | AM179 | |
Rosaceae | Gora | S | AM093 | |
Rosaceae | Hato | S | AM004 | |
Rosaceae | Gora | S | AM086 | |
Polygonaceae | Shabee Haga | H | AM050 | |
Polygonaceae | Shabee | H | AM021 | |
Poaceae | Marga Hori, Qecha | H | AM110 | |
Lamiaceae | Okotu | S | AM015 | |
Lamiaceae | Okotu | H | AM030 | |
Apiaceae | Galee Simbira, Sidissa | H | AM079 | |
Lamiaceae | Toshimbata | H | AM049 | |
Dipsacaceae | Anamuro | H | AM067 | |
Araliaceae | Gatamee | T | AM136 | |
Araliaceae | Ansha | T | AM204 | |
Anacardiaceae | Qondabarbere | T | AM166 | |
Asteraceae | Agadena | H | AM046 | |
Asteraceae | Agadena | H | AM089 | |
Asteraceae | — | H | AM057 | |
Poaceae | Sookora | H | AM127 | |
Solanaceae | Mujule Worabessa | S | AM111 | |
Solanaceae | — | S | AM085 | |
Solanaceae | Hidii | S | AM076 | |
Bignoniaceae | Horoqa | T | AM182 | |
Poaceae | Marga Hilensa (Or) | H | AM088 | |
Poaceae | Chita | H | AM124 | |
Caryophyllaceae | Duqushu, Dinbiba | H | AM108 | |
Loganiaceae | Muluqaa | T | AM133 | |
Gentianaceae | — | H | AM053 | |
Myrtaceae | Badeesa | T | AM117 | |
Rutaceae | Hadheessa | T | AM184 | |
Lamiaceae | Tossigne | H | AM047 | |
Ulmaceae | Tala’aa | T | AM188 | |
Fabaceae | — | H | AM059 | |
Fabaceae | Sidissa (Maget) | H | AM092 | |
Fabaceae | Sidissa | H | AM019 | |
Fabaceae | — | H | AM034 | |
Fabaceae | Sidisa (O), Alfalfa(E) | H | AM038 | |
Malvaceae | Gurbii | H(clim) | AM125 | |
Asteraceae | Qinxxa | H | AM022 | |
Urticaceae | Dobi(Or), Sama(Amh) | S | AM158 | |
Urticaceae | Dobii | H | AM109 | |
Rutaceae | Arabe | T | AM129 | |
Asteraceae | Ebicha | S | AM192 | |
Asteraceae | Rejii | S | AM193 | |
Canellaceae | Bifi, kanafa | T | AM142 | |
Cucurbitaceae | Harola | H(clim) | AM096 | |
Rhamnaceae | Kankura | S | AM195 |
H, herb; S, shrub; T, tree; Li, liana; H (clim), herbaceous climber; E, epiphyte; PH, parasitic herb; Or., Oromifa; Coll. no., collection number.
Woody species density with DBH°>°2 cm was 1567 individuals ha−1. This was relatively higher compared to other similar vegetation areas such as the Wof-Washa forest [
A total of 136 species belonging to 111 genera and 59 families were identified in the edge habitats of the sampled patches, whereas 117 species that belonging to 84 genera and 40 families were recorded in the interior habitats. From the identified life forms, 19 species were trees, 22 species were shrubs, 86 species were herbs, and 7 species were lianas in the edge habitats, whereas 28 species were trees, 21 species were shrubs, 57 species were herbs, and 11 species were lianas in the interior habitats. The overall means (±SE) species richness (35 ± 4.2), Shannon diversity index (2.93 ± 0.17), and Margalef index (5.68 ± 0.69) of the edge habitat were significantly higher compared to the interior habitat at
Mean (±SE) values of species richness and diversity indices.
Diversity indices | Edge habitat | Interior habitat |
---|---|---|
Species richness ( | 35 ± 4.2a | 29 ± 3.6b |
Simpson index ( | 0.10 ± 0.02 | 0.11 ± 0.03 |
Shannon–Wiener index ( | 2.93 ± 0.17a | 2.43 ± 0.11b |
Pielou’s evenness index ( | 0.79 ± 0.05 | 0.83 ± 0.04 |
Whittaker | 1.83 ± 0.26 | 1.34 ± 0.31 |
Margalef index ( | 5.68 ± 0.69a | 3.72 ± 0.92b |
Berger–Parker index ( | 0.19 ± 0.03 | 0.24 ± 0.04 |
Note. Values with different letters indicate significant differences between habitats (
The mean woody species density in the interior habitat (85 ± 22.17 stems ha−1) was significantly higher compared to the edge habitat (70 ± 16.53 stems ha−1) at
Box plot showing woody species density (a) and basal area (b) in the habitats.
Woody species structure in the edge habitats of the BMNP.
Species | Abundance | Basal area (m2 ha−1) | Density (stem ha−1) | Relative density | Relative frequency | Relative dominance | IVI |
---|---|---|---|---|---|---|---|
12 | 1.94 | 9 | 1.79 | 6.35 | 5.18 | 13.32 | |
10 | 4.15 | 8 | 1.49 | 4.76 | 14.81 | 21.06 | |
22 | 2.34 | 17 | 3.28 | 6.35 | 6.27 | 15.90 | |
3 | 0.95 | 2 | 0.45 | 1.59 | 5.08 | 7.12 | |
12 | 7.31 | 9 | 1.79 | 4.76 | 15.64 | 22.19 | |
32 | 6.84 | 25 | 4.78 | 7.94 | 14.62 | 27.34 | |
174 | 1.93 | 136 | 25.97 | 11.11 | 2.95 | 40.03 | |
90 | 6.63 | 70 | 13.43 | 12.70 | 8.87 | 35.00 | |
4 | 0.48 | 3 | 0.60 | 3.17 | 2.59 | 6.36 | |
6 | 0.44 | 5 | 0.90 | 3.17 | 2.34 | 6.41 | |
54 | 0.00 | 42 | 8.06 | 4.76 | 0.00 | 12.82 | |
170 | 0.28 | 133 | 25.37 | 7.94 | 0.61 | 33.92 | |
4 | 1.08 | 3 | 0.60 | 4.76 | 5.78 | 11.14 | |
6 | 0.17 | 5 | 0.90 | 1.59 | 1.79 | 4.27 | |
40 | 0.68 | 31 | 5.97 | 12.70 | 1.21 | 19.88 | |
3 | 0.19 | 2 | 0.45 | 1.59 | 2.01 | 4.05 | |
28 | 6.70 | 22 | 4.18 | 4.76 | 10.24 | 19.18 | |
Total | 670 | 42.13 | 523 | 100 | 100 | 100 | 300 |
IVI: importance value index.
Woody species structure in the interior habitats of the BMNP.
Species | Abundance | Basal area (m2 ha−1) | Density (stem ha−1) | Relative density | Relative frequency | Relative dominance | IVI |
---|---|---|---|---|---|---|---|
6 | 0.71 | 5 | 0.79 | 2.86 | 1.76 | 5.41 | |
16 | 0.25 | 13 | 2.12 | 3.81 | 0.46 | 6.39 | |
142 | 8.64 | 111 | 18.81 | 6.67 | 9.15 | 34.62 | |
4 | 0.08 | 3 | 0.53 | 1.90 | 0.58 | 3.01 | |
74 | 0.83 | 58 | 9.80 | 4.76 | 2.06 | 16.62 | |
3 | 0.02 | 2 | 0.45 | 1.59 | 0.17 | 2.20 | |
18 | 0.42 | 14 | 2.38 | 4.76 | 0.62 | 7.77 | |
3 | 0.02 | 2 | 0.40 | 0.95 | 0.18 | 1.53 | |
40 | 10.43 | 31 | 5.30 | 7.62 | 9.67 | 22.58 | |
8 | 0.05 | 6 | 1.06 | 6.67 | 0.18 | 7.90 | |
128 | 31.54 | 100 | 16.95 | 7.62 | 29.24 | 53.81 | |
4 | 0.01 | 3 | 0.53 | 0.95 | 0.11 | 1.59 | |
6 | 0.03 | 5 | 0.79 | 1.90 | 0.12 | 2.82 | |
4 | 0.03 | 3 | 0.53 | 1.90 | 0.13 | 2.56 | |
49 | 0.06 | 38 | 6.49 | 2.86 | 0.16 | 9.50 | |
3 | 0.04 | 2 | 0.40 | 0.95 | 0.27 | 1.62 | |
32 | 0.10 | 25 | 4.24 | 1.90 | 0.37 | 6.51 | |
32 | 1.13 | 25 | 4.24 | 6.67 | 1.20 | 12.10 | |
8 | 0.72 | 6 | 1.06 | 1.90 | 1.77 | 4.73 | |
6 | 0.17 | 5 | 0.79 | 2.86 | 1.24 | 4.89 | |
78 | 6.66 | 61 | 10.33 | 7.62 | 6.18 | 24.13 | |
3 | 0.24 | 2 | 0.40 | 0.95 | 1.79 | 3.14 | |
8 | 2.61 | 6 | 1.06 | 3.81 | 4.83 | 9.70 | |
4 | 0.08 | 3 | 0.53 | 1.90 | 0.31 | 2.74 | |
3 | 0.20 | 2 | 0.40 | 0.95 | 1.49 | 2.84 | |
28 | 0.28 | 22 | 3.71 | 3.81 | 0.52 | 8.04 | |
35 | 9.55 | 27 | 4.64 | 6.67 | 23.60 | 34.90 | |
4 | 0.25 | 3 | 0.53 | 1.90 | 0.94 | 3.37 | |
6 | 0.25 | 5 | 0.79 | 1.90 | 0.94 | 3.64 | |
Total | 755 | 75.41 | 590 | 100 | 100 | 100 | 300 |
IVI: importance value index.
IVI of woody species in the edge and interior habitats.
Species | Relative density (%) | Relative frequency (%) | Relative dominance (%) | IVI | ||||
---|---|---|---|---|---|---|---|---|
Edge | Interior | Edge | Interior | Edge | Interior | Edge | Interior | |
11.72 | 20.13 | 8.79 | 11.94 | 11.98 | 25.03 | 32.49 | 37.10 | |
2.86 | 22.33 | 4.40 | 10.45 | 8.47 | 7.83 | 15.73 | 40.61 | |
5.21 | 5.03 | 5.49 | 11.94 | 19.76 | 8.28 | 30.47 | 25.25 | |
3.65 | 5.35 | 7.69 | 4.48 | 13.84 | 20.21 | 25.18 | 30.03 | |
5.21 | 12.26 | 6.59 | 11.94 | 1.64 | 5.29 | 13.44 | 29.49 | |
22.14 | 5.03 | 5.49 | 2.99 | 0.82 | 0.31 | 28.45 | 8.33 | |
1.56 | 11.64 | 3.30 | 7.46 | 4.01 | 9.29 | 8.87 | 28.38 | |
22.66 | — | 7.69 | — | 3.99 | — | 34.34 | — | |
1.57 | — | 4.48 | — | 8.79 | — | 14.84 | — | |
4.17 | — | 7.69 | — | 2.33 | — | 14.19 | — |
The computed regression analysis among the landscape indices and species composition and structural parameters in this study revealed that only PN and AREA_MN significantly affected both the species composition and structural properties of the study area. Accordingly, PN was strong and negatively affected the overall species richness (
Pearson's correlation coefficient between the landscape indices and floristic composition and structural parameters.
1 | |||||||||||
0.95 | 1 | ||||||||||
BA | 0.96 | 0.94 | 1 | ||||||||
Density | 0.99 | 0.90 | 0.93 | 1 | |||||||
PN | −0.90 | −0.96 | −0.96 | −0.84 | 1 | ||||||
AREA_MN | 0.95 | 0.87 | 0.82 | 0.72 | −0.71 | 1 | |||||
SHAPE_AM | −0.42 | −0.64 | −0.53 | −0.28 | 0.48 | −0.01 | 1 | ||||
COA | −0.56 | −0.37 | 0.34 | 0.66 | −0.87 | 0.41 | −0.79 | 1 | |||
ED | 0.65 | 0.78 | −0.77 | −0.54 | 0.54 | −0.91 | 0.25 | −0.16 | 1 | ||
ENN_MN | −0.37 | −0.56 | −0.59 | −0.28 | 0.77 | −0.26 | 0.73 | −0.81 | 0.04 | 1 | |
IJI | −0.42 | −0.28 | −0.32 | −0.37 | 0.58 | −0.59 | 0.37 | −0.61 | 0.37 | 0.1732 | 1 |
BA | Density | PN | AREA_MN | SHAPE_AM | COA | ED | ENN_MN | IJI |
Note. The star indicates significant level between values (
Besides, modifying the spatial pattern of the landscape habitat size reduction and increase in isolation cause an alteration in the dispersal rate, affecting survival and mortality of individuals [
Among the landscape indices computed, only PN and AREA_MN significantly affected some of the floristic structural properties assessed. Thus, the PN was strong and negatively affected the woody species density (
This study recognized that the Bale Mountains National Park has a diverse biodiversity and is an ecologically significant area. It contains a variety of life forms with good ecological integration. It also harbors a number of endemic floras and faunas. However, currently, anthropogenic disturbances strongly impaired the plant species composition and structure as well as the overall ecological integrity of the landscape. The progressive settlement and agricultural land expansion at the expense of natural forest and grassland coupled with human-induced recurrent fire and livestock grazing in park became a potential threat to the landscape structure. This was due to the escalated human and livestock population and their corresponding demands and necessities increment in the park. Both the floristic composition and structure were affected by the expansion of edge habitat and shrinkage of interior habitat. Species richness and diversity were higher in the edge habitat, whereas density, frequency, and basal area were higher in the interior habitat. Therefore, maintenance of the habitats heterogeneity in the park is essential for long-term population persistence. Moreover, human activities in the park should be banned and settlements in the park should be relocated to other areas to avoid their potential impacts on the floras and faunas. Finally, studies on microenvironmental factors such as light availability, air and soil temperature, humidity, and soil nutrients along the edge and interior gradient should be conducted to determine their effect on species richness, composition, and structure.
The data used to support the findings of this study are included within this paper.
The authors declare that there are no conflicts of interest.
The authors would like to express their special thanks to the Ethiopian Wildlife Authority for giving permission to conduct this study on-site.