Ethiopia is one of the top 25 biodiversity-rich countries in the world, and hosts two of the world’s 34 biodiversity hotspots, namely the Eastern Afromontane and the Horn of Africa hotspots. It is also among the countries in the Horn of Africa regarded as major Centre of diversity and endemism for several plantspecies. The Ethiopian flora is estimated to about 6000 species of higher plants of which 10% are considered to be endemic according to Institute of Biodiversity Conservation (IBC) of Ethiopia, 2012 and woody plants constitute about 1000 species out of which 300 are trees.Forests form the major constituents of vegetation resources and thus conservation of forest genetic resources (FGRs) is among the priority areas of biodiversity conservation in Ethiopia. Forests undergo changes in various ways. Its areas can be reduced either by deforestation or by natural disasters such as volcanic eruptions. As a result, the expanse or vastness of forest areas is declining across the globe, partly through logging activities and also due to conversion of habitats to croplands (agricultural expansion) accounts for up to 40 percent of Ethiopian forest losses. A woodyplant is a plant that produces wood as its structural tissue. In Ethiopia, biodiversity varies in space and time, and understanding patterns and drivers of Variation in biodiversity distribution has been a central topic in ecology. A diversity index is a mathematical measure of species diversity in a given Community. Based on the species richness (the number of species present) and species abundance (the number of individuals per species). Limited governmental, institutional, and legal capacity; population growth; land degradation; weak management of protected areas; and deforestation, invasion of exotic species, habitat destruction and fragmentation, over utilization, pollution, climate change, trade and transportation are some of threats and causes for loss to biodiversity of Ethiopia. To identify the richness, evenness, endemism, exoticness, enlargement, extinction rate, and to know appropriate management approach, diversity assessment has indispensable role. And ecologists and other related researchers and scientists use different indices to calculate diversity parameters. Among the indices, Shannon and Simpsons indices are commonly used one. Strong work is required to conserve diversity of Ethiopia.
DOI: 10.9734/AJRAF/2019/v3i230034 Editor(s): (1) Dr. Mohan Krishna Balla, Retired Professor,Tribhuvan University, Institute of Forestry, Nepal. (2) Dr. Nebi Bilir, Professor, Forestry Faculty, Isparta University of Applied Sciences, 32260 Isparta, Turkey. Reviewers: (1) Paul Kweku Tandoh, Kwame Nkrumah University of Science and Technology, Ghana. (2) William Ballesteros Possu, Universidad de Nariño, Colombia. (3) Bharat Raj Singh, Dr. APJ Abdul Kalam Technical University, Lucknow, India. Complete Peer review History: http://www.sdiarticle3.com/review-history/48509
In Ethiopia Exclosures has been recognized as promising practice in the restoration of degraded land and regulating the environmental services. Though, study on the role of exclosures on rehabilitating of degraded land is very little, fragmented and doesn’t often integrate the regulating environmental services. To scale up this practices insight to the Ethiopian level, I carry out reviewing different research articles on the role of exclosure to biodiversity of woodyspecies and regulating ecosystem services. The review of this study showed that exclosure significantly enhanced woodyspecies diversity; reducing soil erosion, improve Soil nutrient contents and the ecosystem carbon stock potential over the adjacent communal grazing lands. In addition to this establishing exclosures has a high contribution to the livelihood of local communities. As a result the local communities have a positive attitude towards the establishment of exclosures in the degraded lands. Overall review from this study strongly indicates that establishment of exclosures in the degraded lands of Ethiopia are a win-win situation since it is advantageous over the people, natural and climate of the country. However, by involving the key stakeholders the governmental and nongovernmental organizations (NGOs’) should have to expand this practice to whole degraded lands of the country.
This study has shown that the consequence of human disturbance on woodyplant diversity was both positive and negative depending on the type and intensities of the disturbances. Disturbance had resulted in increased species richness and population density of trees, shrubs and overall woodyspecies in the MD sites compared to the LD sites. The converse was true for the HD site where intensities crop cultivation and settlement encroachments are practiced. However, the increased diversity in the moderately disturbed site was due to additions of shrub species, which are known to have affinities to disturbed habitats. Since the central goal of conservation is to maintain maximum diversity of native species (Hobbs and Huenneke 1992), the high diversity reported in the moderately disturbed site in the present study should, therefore, be interpreted carefully. This is because such non-native species could displace the original species through succession; perhaps, leading to ecosystem alterations. Therefore, the current ranger-based resource protection activities practiced in the LD should be strengthened, and should be extended to the MD and HD sites in order to mitigate the prevailing disturbances in the areas reported here. Alternatively, designating the forests as community-based conservation areas might be useful to ensure a regulated and sustainable natural resource use in the areas. Finally, future studies focusing on the impacts of disturbances on the regeneration and population structure of woodyspecies in the present area would be of paramount to increase our understanding of the subject matter.
Indiscriminate charcoal productions, timber harvesting, demand for farmlands and overgrazing have aggravatedland degradation process in the tropical regions. At each point of this cycle, species are lost and biodiversity is obtainable only in the National Parks, Game reserves, Forest reserves, Wildlife sanctuaries. Forests and its resources are important assets that the tropical regions can sustainably manage for its renewable potentials, environmental benefits and socio- economic importance to mankind. Thus, this paper aim at reviewing past research works to provide profound solutions for conservation and restoration of forests and its products in the mid of financial shortcoming among the developing nations in the tropical regions. Based on this review, endangered plantspecies such as Prosopis africana, Parkia biglobosa, Khaya senegalensis, Gleditsia assamica, Gymnocladus assamicus, Aquilaria malaccensis and others can be restored; and genetic heredity (with qualitative characteristics) can be sustain for generational use if only we will all ignore the voice that “demands high financial resources for the management of endangered species before it can be conserved and restored”. Even without the provision of financial resources for conservation and restoration of endangered species, with high interest and euphoria among the youths, the young populace can conserved and restored the tropical forests and its biodiversity in the regions. This can be achieved by frequent inclusion of youths in decisions making and the use
Sowing native seed can be an effective method of restoring native vegetation if rates of seed germination and seedling survival are high. In New Zealand, this method has been tested in lowland forest remnants (Overdyck et al. 2013), wetlands (Burge 2015), regenerating mānuka (Leptospermum scoparium) shrublands (Davis et al. 2013), and at sites invaded by woody weeds (Burrows et al. 2015; McAlpine et al. 2016). In all cases, sowing seed increased seedling numbers, indicating that native plant recruitment may be limited by seed and/or safe site availability (Duncan et al. 2009) in a wide range of ecosystem types in New Zealand. In the current study, seed addition generally resulted in higher numbers of seedlings, although recruitment was variable among species, and most species also recruited naturally from the seed rain or seed bank. Recruitment success did not appear to be related to seed size. Standish et al. (2001) also found seed size to be a poor predictor of native plantspecies abundance where tradescantia was present. Other factors, such as differences in shade tolerance (Standish 2002; Grubb et al. 2013), may be playing a role. For example, the lesser shade tolerance of K. excelsa could be a reason for its low seedling survival in the current study, particularly at the three sites where mean canopy openness was below 10%, the suggested threshold at which a species that benefits from canopy openness might be disadvantaged compared with a shade-tolerant species (Lusk et al. 2013, 2015).
The type, composition, distribution, and density of seedlings and saplings indicate the future regeneration status of the forest. The various studies showed that open canopy might be in favor of seed germination and seedling establishment through increased solar radiation on the forest floor (Khan et al., 1987; Kadavul et al., 1999). The present study result of seedling and sapling to the parent plant ratio showed that the distribution of mature individuals is greater than seedlings and sapling indicate that the regeneration status of the forest is at the low state. Compared to matured individuals, there were less sapling populations implying the perishing off of most seedlings before reaching sapling stage due to factors such as closed canopy, human intervention, browsers, grazers, Climatic and nature of the seeds. One of the criteria to establish conservation priority classes among species in Weiramba Forest is the description of the regeneration status. Regeneration is a critical phase of forest management because it maintains the desired species composition and stocking after disturbances (Duchok et al., 2005). The Current study results showed that Myrsine Africana, Euclea divinorum, and Dodonaea anguistifolia species have high regeneration status.
Vegetation is complex in nature and its structure and composition differs from place to place because of varying 2006; Raturi, 2012). High mountain ranges are considered as hotspots of phytodiversity due to their climatic complexity, location within frequency and amount of natural disturbances. The number of species in mountain area depends on these The Himalayas encompass diverse and characteristic vegetation distributed over a wide range of Dhaulkhandi et al., 2008). It ranges from tropical dry deciduous forests in the foothills to alpine meadows above timberline (Singh and Both structure and diversity of vegetation have strong functional role in controlling ecosystem process like biomass production, cycling of water and nutrient (Gower et 1992). Phytosociological analysis and population structure of forests in Himalayan subtropical regions have been studied . (2006); Kharkwal t and Chandhok (2009); Todoria et al. (2010); (2010); Gairola et Significant work in the field has also been done in the
OALibJ | DOI:10.4236/oalib.1102576 5 April 2016 | Volume 3 | e2576 of diversity indices of woodyspecies at Tula forest were relatively higher than Kaja Araba forest. Site characte- ristic heterogeneity could be the reason for observed differences in woodyspecies diversity. Agro-ecological factors such as altitude, temperature and soil quality could be a source of variation in plant diversity . Be- sides, low human disturbance at Tula forest as it is less accessible site than Keja Araba could be another factor that generates difference in woodyspecies diversity. Such results are consistent with study of Zegeye et al.  in northwestern Ethiopia, who reported negative effect of site accessibility on woodyspecies diversity. Forest disturbance influences species through alteration and fragmentation of forests, which is a serious concern in the management tropical forests . The evenness value (0.86) for Tula forest showed that there is more or less ba- lanced distribution of individuals of different species than Keja Araba forest. On the other hand, the low even- ness for Keja Araba forest with comparing to that of Tula indicated that there is unbalanced representation of in- dividuals of different species because of high human disturbance as well as site and species characteristics. The reason for low evenness can be attributed to excessive disturbance, variable conditions for regeneration and over-exploitation of some species . The diversity and evenness indices imply the need to conserve the fo- rests at Keja Araba site from human disturbance.
The concept of extinction debt (sensu [ 5 ]) implies that extinction of species can take place with a considerable delay after the event of habitat loss or any other deterministic change has occurred. Several factors may influence the occurrence and extent of extinction debts as well as the time elapsed until reaching a new equilibrium within a community (i.e., relaxation time [ 6 ]). The magnitude and spatial scale of habitat loss will determine the degree of connectivity of remaining habitat at the landscape level, affecting the persistence and viability of certain spe- cies [ 6 , 7 ]. Extinction debts are more likely to be paid off more slowly in moderately frag- mented landscapes with high connectivity or large patches of remaining habitat nearby and more quickly in highly fragmented landscapes, with smaller remaining forest fragments and low habitat cover in their surroundings [ 6 , 8 ]. On the other hand, within remaining forest frag- ments, some species will be more susceptible to undergo delayed extinction. For example, long-lived species are particularly likely to face delayed extinctions [ 6 , 9 ]. In the case of plants, woodyspecies such as trees and shrubs are long-lived and thus persist longer in chronically small and isolated forest fragments and also have several reproductive opportunities through- out time to yield and recruit successful progeny (e.g. [ 10 , 11 ]). In contrast, non-woodyspecies such as grasses, herbs, and herbaceous vines have higher turnover rates as their lifespan is, in general, much shorter than woodyspecies [ 12 ]. As a result, short-lived non-woodyplant spe- cies are likely to pay off faster the extinction debt than long-lived woodyspecies [ 6 , 10 , 11 ].
Elaeagnaceae E. parvifolia Royle Wall. ex Shrub Kankoli Anti cancer and cardiac stimulant, Fruit is juicy, sweet and pleasant, used as a raw jam and preservative. The flowers are stimulant, cardiac and astringent. The seeds are used in curing cough and pulmonary infections. The wood is used as fuel. Euphorbiaceae M. philipinensis Muell (Lam) Tree Kamlila The fruits are crushed and used orally to treat bloody diarrhoea. The leaves are used as “Koochan” to wash utensils. The leaves are used as fodder and branches for fuel. Fabaceae B. monosperma Lam. Tree Chichra
Root is useful in night blindness, helminthiasis, piles,ulcer and tumours. Flowers are useful in diarrhoea, astringent, diuretic, depurative, tonic, leprosy, skin diseases,gout, thirst, burning sensation. It is used for timber, medicine and dye. Leaves are used as fodder. This plant is important source of charchol. Due to leathery nature of leaves they are not usally taken by the cattles.
Few terrestrial ecosystems lack ants. Given their vast num- bers and diverse roles as predators, prey, scavengers and mutualists, they are tightly woven into the fabric of eco- logical communities (Ho¨lldobler and Wilson, 1990 ). Their activities influence the structure and function of communi- ties and can have ecosystem-level effects (Ho¨lldobler and Wilson, 1990 ; Wagner and Jones, 2006 ; Sanders and van Veen, 2011 ). Aphaenogaster is one of the most abundant ant genera in eastern US deciduous woodlands (Mitchell et al., 2002 ; Giladi, 2004 ; Ellison et al., 2007 ; Warren et al., 2010 ), and A. rudis is considered a keystone mutualist based on its role as a dominant seed disperser (Ness et al., 2009 ). This role means that its activities influence both the abundance and distribution of many understory plantspecies (Zelikova et al., 2008 ; Ness et al., 2009 ; Warren et al., 2010 ). Less is known about Aphaenogaster’s interactions with other woodland species, and its potential roles in forest ecosystem function.
Received: 21 November 2011 – Revised: 22 March 2012 – Accepted: 2 April 2012 – Published: 20 April 2012 Abstract. The time between introduction of an alien species and escape from cultivation shows considerable variation among species. One hypothesis to explain this variation of the time lag invokes the evolution of genotypes adapted to the conditions of the new environment. Here, we analyse the variation in time lags among 53 alien woodyplantspecies in Germany. Accounting for the e ff ects of time since introduction, growth form (trees versus shrubs), biogeography and taxonomic isolation (presence or absence of a native congener in the adventive area) we found that the time lag decreases with increasing polyploidization. By contrast, the haploid chromosome number was not significantly related to the time lag. These results provide evidence for the hypothesis that recent genome duplication events are important for a fast escape from cultivation of an alien woodyplantspecies. We suggest that a large number of duplicated chromosomes increase the partitioning of the genome and hence the average rate of recombination between loci facilitating the formation of adaptive genotypes.
Sustainable and close-to-nature forest management (small-scale cutting, rejuvenation in small gaps etc.), in- cluding conservation management of studied riparian and
flooded forests, should give priority to enable the rejuve- nation of key tree species which is now disabled due to presence of IAS. According to the fact that IAS are main- ly light demanding species some sylvicultural measures should be considered. Restricting the influx of light with keeping tree crown densities thick, mostly with low log- ging intensity (especially in the FHT 91F0), site prepara- tion for planting and artificial rejuvenation with adequate regional tree reproductive material, planted mainly with tall, few years old seedlings, are just some of the measures. Our study showed that the type and intensity of forestry measurement utilized in floodplain forests play an impor- tant role in intrusion of IAS. Privately owned forests, ir- respective of the FHT, which turned out as the forests with less dense canopy cover and consequently with higher light intensity are in our case more prone to the intrusion of IAS.
In Kenyan drylands the major reported invader is Mesquite. This is one of the most widespread dryland invasive species in north and east Africa, having already invaded 500 000 and 700 000 hectares in Kenya and Ethiopia, respectively. Under ideal conditions, it has the ability to double its range every 5 years (IUCN, 2010). Although initially introduced to stabilise the drylands by revegetating barren land, Mesquite went on to outcompete and replace the native plants and trees. It has been blamed for many disaster-effects such as replacing the foliage (grasses, herbs and shrubs) eaten by local livestock, injuring livestock with its poisonous thorns and causing goat teeth to rot and fall out because the small seeds get stuck between the teeth (Table 1). Thousands of goats have been rendered toothless and died from starvation following teeth loss. In addition the roots of Mesquite make the soil loose and unable to sustain water; thus enhancing drought and soil erosion. Furthermore, because of its aggressive growth the plant forms thickets that are an ideal breeding ground for mosquitoes that transmit malaria. Another serious invasive plant is the prickly pear cactus or Opuntia ficus indica. This plant, which has been blamed for destroying grazing land in the Kenyan and Tanzanian drylands, is originally from Mexico. It was introduced as a hedge plant but has become a serious and difficult to control pest, because it spreads rapidly degrading the dry lands. Other prolific woody invasive plantspecies include the Lantana and the Acacia polycantha (White thorn) tree. All these invasive plants and trees have had serious socio-economic impacts and ultimately increased poverty in the local communities.
Chile has more than half of the temperate forests in the southern hemisphere. These have been included among the most threatened eco-regions in the world, because of the high degree of endemism and pres- ence of monotypic genera. In this study, we develop empirical models to investigate present and future spatial patterns of woodyspecies richness in temperate forests in south-central Chile. Our aims are both to increase understanding of species richness patterns in such forests and to develop recommendations for forest conservation strategies. Our data were obtained at multiple spatial scales, including ﬁeld sam- pling, climate, elevation and topography data, and land-cover and spectrally derived variables from satel- lite sensor imagery. Climatic and land-cover variables most effectively accounted for tree species richness variability, while only weak relationships were found between explanatory variables and shrub species richness. The best models were used to obtain prediction maps of tree species richness for 2050, using data from the Hadley Centre’s HadCM3 model. Current protected areas are located far from the areas of highest tree conservation value and our models suggest this trend will continue. We therefore suggest that current conservation strategies are insufﬁcient, a trend likely to be repeated across many other areas. We propose the current network of protected areas should be increased, prioritizing sites of both current and future importance to increase the effectiveness of the national protected areas system. In this way, target sites for conservation can also be chosen to bring other beneﬁts, such as improved water supply to populated areas.
With regard to fractional woody cover mapping, there have been many efforts at regional and global scales (DeFries et al., 2000; Hansen et al., 2002, 2011; Brandt et al., 2016). MODIS and Landsat vegetation continuous fields (MODIS VCF and Landsat VCF) of tree cover have been available globally and benefited related research and application communities (DiMiceli et al., 2011; Sexton et al., 2013). However, the reliability of these products may be contested when derivation of training data draws from discrete land cover classification system (e.g., woodland, grassland) (DeFries et al., 2000). Moreover -- and problematic in areas with shorter woody plants -- their training data only account for woody plants above 5m height (Hansen et al., 2002; Sexton et al., 2013), further weakening their efficiency in savanna areas where many short woody plants exist. These limitations have also been reported in other similar studies (DeFries et al., 2000; Hansen et al., 2011) and noted as potentially limiting practicability for savanna ecosystems where short woody vegetation is the most typical morphology.
by Akoto et al. , who described that vegetation in the vicinity of railway servicing workshops in Kumasi city of Ghana was severely affected. The root, stem, leaf and seedling dry weights of A. nilotica seedlings grown in soil of Karachi Cantonment Station were significantly reduced as compared to University Campus, Drighroad Junction, Malir Station and Landhi Junction. The same results were coated by Iqbal and Shafiq , who described that the reduction in leaf number, plant height, circumference, root, shoot and total plant dry weights of Prosopis juliflora and Blepharis sindica were suppressed due to low contents of calcium carbonate, high electrical conductivity and high contents of sodium and potassium salts.
To collect the vegetation data two pre-structured; woodyplantspecies inventory and regeneration status assessment forms were used. However, in the beginning, the physiognomy and type of the vegetation were described before going for collecting the vegetation data. Thereafter, for each woodyplantspecies appeared in the sample plots and for trees and shrubs having the DBH 2.5 cm, DSH/ DBH was measured using the graduated Caliper while the data of total height was taken on ocular estimation. For shrubs possessing several stems rising from below DBH, each branch was measured for DSH/ DBH and height as individual stem and number of stems were also counted duly. Moreover, together with this, the growth habit and number of stems of each species existing in the plots were described and recorded. The types of the woodyplantspecies were recorded using local names. On the other hand, the data of the saplings and seedlings of woodyplantspecies were collected from the sub-quadrates as described above. Simultaneously, plant specimens were collected and pressed in the field using the plant presser. These specimens were dried, identified, mounted