Assessment of impact of ecological elevation on grass species diversity in Yabello Rangeland, Southern Ethiopia

Elevation has great impact on species’ diversity; it creates ecologically diverse vegetation. Studying species’ richness patterns at different scales is very important both for ecological explanations and effective conservation design. In this study, grass vegetation data were collected using systematic sampling methods. 18 transects and 54 quadrants were laid, with 6 transects and 18 quadrants from each selected study kebele having 1 × 1 m2 for grass. In each quadrant, the level of impact for each threatening factor was evaluated and a total of 26 grass species were recorded. The data were analyzed using SPSS and the average species’ composition was assessed in relation to topographic variables. There was upper elevation observed in both richness and diversity of plant species compared to the others with significant P<0.05. Grazing intensity also has significant impact on both species’ diversity, density and area coverage. This shows that the area heavily grazed had less diversity richness and coverage compared to the less grazed (p<0.001) area. From the data we can summarize that anthropogenic, topographic and climate factors were the leading causes of the overall shift of plant community structure in the study area.   Key words: Elevation, grazing intensity, grass composition, Kebele.

[1]  Jintun Zhang,et al.  Effects of elevation and disturbance gradients on forest diversity in the Wulingshan Nature Reserve, North China , 2016, Environmental Earth Sciences.

[2]  Wendawek Abebe,et al.  Floristic Composition and Vegetation Structure of Woody Species in Lammo Natural Forest in Tembaro Woreda, Kambata-Tambaro Zone, Southern Ethiopia , 2016 .

[3]  Z. Woldu,et al.  The effects of disturbance on the population structure and regeneration potential of five dominant woody species – in Hugumburda‐Gratkhassu National Forest Priority Area, North‐eastern Ethiopia , 2016 .

[4]  Simon Shibru,et al.  Floristic Composition, Vegetation Structure, and Regeneration Status of Woody Plant Species of Oda Forest of Humbo Carbon Project, Wolaita, Ethiopia , 2015 .

[5]  T. Soromessa,et al.  Carbon Stock Analysis Along Altitudinal Gradient in Gedo Forest: Implications for Forest Management and Climate Change Mitigation , 2015 .

[6]  T. Soromessa,et al.  Carbon Stock Variations Along Altitudinal and Slope Gradient in the Forest Belt of Simen Mountains National Park, Ethiopia , 2015 .

[7]  P. Billi,et al.  Increased frequency of flash floods in Dire Dawa, Ethiopia: Change in rainfall intensity or human impact? , 2015, Natural Hazards.

[8]  Bin Zhang,et al.  Functional diversity of Cercidiphyllum japonicum, communities in the Shennongjia Reserve, central China , 2015, Journal of Forestry Research.

[9]  A. Angassa.  EFFECTS OF GRAZING INTENSITY AND BUSH ENCROACHMENT ON HERBACEOUS SPECIES AND RANGELAND CONDITION IN SOUTHERN ETHIOPIA , 2014 .

[10]  Zewde Achiso.  Distribution of the Woody Vegetation along the Altitudinal range from Abay (Blue Nile) Gorge to Choke Mountain, East Gojjam Zone, Amhara National Regional State, Northwest Ethiopia. , 2014 .

[11]  R Core Team,et al.  R: A language and environment for statistical computing. , 2014 .

[12]  Hans Juergen Boehmer,et al.  PLANT DIVERSITY, VEGETATION STRUCTURE AND RELATIONSHIP BETWEEN PLANT COMMUNITIES AND ENVIRONMENTAL VARIABLES IN THE AFROMONTANE FORESTS OF ETHIOPIA , 2015 .

[13]  Jintun Zhang,et al.  Vegetation Patterns and Species Diversity Along Elevational and Disturbance Gradients in the Baihua Mountain Reserve, Beijing, China , 2013 .

[14]  W. Ru.  ECOLOGICAL STUDY OF FORESTS DOMINATED BY ENDANGERED SPECIES, TAXUS CHINENSIS VAR. MAIREI, IN SHANXI OF CHINA , 2012 .

[15]  Adane Girma Gebreselasse.  Plant Communities, Species Diversity, Seedling Bank and Resprouting in Nandi Forests, Kenya , 2012 .

[16]  L. Vijayan,et al.  Distribution pattern of trees along an elevation gradient of Eastern Himalaya, India , 2011 .

[17]  V. Pechanec,et al.  Floristic diversity patterns in the White Carpathians biosphere reserve, Czech Republic , 2011, Biologia.

[18]  H. Birks,et al.  Recent vegetation changes at the high‐latitude tree line ecotone are controlled by geomorphological disturbance, productivity and diversity , 2010 .

[19]  T. Bekele,et al.  Vegetation composition in Hugumbirda-Gratkhassu national forest priority area, South Tigray. , 2010 .

[20]  D. Byarugaba,et al.  Impact of land use on the ecology of uncultivated plant species in the Rwenzori mountain range, mid western Uganda. , 2009 .

[21]  E. Schlecht,et al.  Vegetation patterns and diversity along an altitudinal and a grazing gradient in the Jabal al Akhdar mountain range of northern Oman , 2009 .

[22]  K. Takeuchi,et al.  Comparison of vegetation changes along grazing gradients with different numbers of livestock , 2009 .

[23]  E. Aynekulu,et al.  Regeneration Response of Juniperus procera and Olea europaea subsp cuspidata to Exclosure in a Dry Afromontane Forest in Northern Ethiopia , 2009 .

[24]  C. M. Sharma,et al.  Species richness and diversity along an altitudinal gradient in moist temperate forest of Garhwal Himalaya. , 2009 .

[25]  S. Demissew,et al.  Dryland woody vegetation along an altitudinal gradient on the eastern escarpment of Welo, Ethiopia , 2008 .

[26]  Ashwani Kumar Thukral,et al.  Plant species diversity along an altitudinal gradient of Bhabha Valley in western Himalaya , 2008 .

[27]  Jintun Zhang,et al.  Relationships between vegetation and climate on the Loess Plateau in China , 2006, Folia Geobotanica.

[28]  Jintun Zhang,et al.  Diversity and Composition of Plant Functional Groups in Mountain Forests of the Lishan Nature Reserve, North China , 2007 .

[29]  A. Marshall,et al.  Changes in tropical forest vegetation along an altitudinal gradient in the Udzungwa Mountains National Park, Tanzania , 2006 .

[30]  J. Isselstein,et al.  Rangeland condition and trend in the semi-arid Borana lowlands, southern Oromia, Ethiopia , 2006 .

[31]  H. H. Bruun,et al.  Effects of altitude and topography on species richness of vascular plants, bryophytes and lichens in alpine communities , 2006 .

[32]  M. Fetene,et al.  Diversity of Afroalpine Vegetation and Ecology of Treeline Species in the Bale Mountains, Ethiopia, and the Influence of Fire , 2006 .

[33]  A. Mengistu.  RANGE MANAGEMENT FOR EASTERN AFRICA CONCEPTS AND PRACTICES , 2006 .

[34]  A. Solow,et al.  Measuring biological diversity , 2006, Environmental and Ecological Statistics.

[35]  C. Carpenter.  The environmental control of plant species density on a Himalayan elevation gradient , 2005 .

[36]  F. Sterck,et al.  Ethiopian Church Forests: Opportunities and Challenges for Restoration. , 2004 .

[37]  F. Maestre.  On the importance of patch attributes, environmental factors and past human impacts as determinants of perennial plant species richness and diversity in Mediterranean semiarid steppes , 2004 .

[38]  G. Austrheim,et al.  Plant diversity patterns in semi-natural grasslands along an elevational gradient in southern Norway , 2002, Plant Ecology.

[39]  T. Soromessa,et al.  Ecological study of the vegetation in Gamo Gofa Zone, Southern Ethiopia , 2004 .

[40]  J. Grytnes,et al.  Distribution of vascular plant species richness and endemic richness along the Himalayan elevation gradient in Nepal , 2002 .

[41]  O. Eriksson,et al.  Plant species diversity and grazing in the Scandinavian mountains - patterns and processes at different spatial scales , 2001 .

[42]  N. Stenseth,et al.  Relationships between biomass and plant species richness in arid-zone grazing lands , 2001 .

[43]  R. Alexander,et al.  Vegetation Mapping: From Patch to Planet , 2000 .

[44]  J. Karr.  Biological diversity: The coexistence of species on changing landscapes: by Michael A. Huston Cambridge University Press, 1994. £60.00/$100.00 hbk, £24.95/$34.95 pbk (xix + 681 pages) ISBN 0 521 36093 5 , 1995 .

[45]  D. H. Knight,et al.  Aims and Methods of Vegetation Ecology , 1974 .