Morphological and anatomical studies on Tacca leontopetaloides (L.) Kuntze (Taccaceae) in Nigeria

Tacca leontopetaloides is the only species in the genus Tacca naturally distributed in the Guinea savannah and dry rainforest regions in Nigeria. The study was conducted to contribute to scientific knowledge on the macro-morphological and anatomical features of the plant collected from 4 locations (Akoko, Eruwa, Bazza and Ile-Ife) across the Nigeria and to determine the effect of environmental factors on its anatomy. Leaf epidermal peel of the 4 samples, leaf and stem Transverse Sections (T.S) and stem Tangential Longitudinal Section (T.L.S) and Radial Longitudinal Section (R.L.S) as well as stem fibres were prepared and studied. A wide range of similarities and differences were noted in the anatomical features of the 4 samples studied. The similarities include, but not limited to stomata being anomocytic, epidermis hypostomatic, cuticle single-layered and striated, vascular bundles conjointed collateral, epidermis undulating, stem rays uniserrate and procumbent, stem fibres non-septate and non-storeyed. Wide range of variations are noted in stomata density and measurements, epidermal cell density, guard cell measurements, cuticle thickness, vascular bundle arrangement, shapes of parenchyma and sclerenchyma cells and many other anatomical features. The variations observed among the samples studies were attributed to the prevailing environmental factors in each collection site.Morphological and anatomical studies on Tacca leontopetaloides (L.) Kuntze (Taccaceae) in Nigeri

Multi-empirical investigations on the population genetic structure, ecological niche, and regeneration of Ivesia webberi with conservation implications

Ecosystems often contain a few cosmopolitan species and a large number of rare species. Despite their relative low abundance and biomass, rare species support the multifunctionality and resilience of ecosystems. Therefore, empirical studies on rare and range-restricted species can increase our understanding of eco-evolutionary underpinnings of species and ecosystem persistence, and generate sufficient knowledge to design effective conservation programs. These research studies can also benefit conservation programs for rare and range-restricted species, which are often prioritized. This research focuses on Ivesia webberi, a federally threatened perennial forb and the vegetative communities that harbor the species. Specifically, empirical studies investigated the following: (1) species-environment relationship of I. webberi using iterative and multi-year ecological niche modeling with complementary model-guided sampling, to describe and predict suitable habitats; (2) the relationship between soil seed bank and aboveground vegetation in plant communities where I. webberi is found, to understand the regeneration niche of I. webberi and assess ecological resilience of the vegetative communities; (3) genetic diversity, structure, and functional connectivity among I. webberi populations in order to characterize genetic resources and therefore evolutionary potential; (4) the relationships between genome size variation and bioclimatic variables within I. webberi and among Ivesia taxa; and (5) seed viability of I. webberi, including spatiotemporal variability and storage behavior.Findings from the 5-year iterative niche modeling study resulted in the discovery of seven novel populations, an expansion of the known species distribution range, and identification of important environmental drivers of the ecological niche of I. webberi. Native species richness was higher in aboveground vegetation in the sampled sites where I. webberi occurs while the soil seed bank is dominated by invasive annual grasses. This resulted in low floristic similarity between the aboveground vegetation and the soil seed bank, and highlights the importance of seeding with native plants and control of invasive plant species to maintain the ecological legacies of these sites in the Great Basin Desert. Genetic diversity is relatively low across I. webberi populations and exhibited significant spatial genetic structure; functional connectivity was influenced by synergistic effects of geographic distance and landscape features. However, I. webberi exhibits a significant temporal, not geographical, variation in seed viability, and seed viability potentially reduces with storage time suggesting a recalcitrant behavior. Seed viability can be reliably estimated and monitored using non-destructive x-ray imagery and multispectral imaging techniques. An 8-fold variation in genome size of 31 Ivesia taxa was observed, ranging from 0.73 pg/2C in I. baileyi var. beneolens to 5.91 pg/2C in I. lycopodioides ssp. megalopetala. This genome size variation significantly correlated with actual evapotranspiration and seed size. Inference from genome size suggest that all sampled Ivesia are diploid with 28 chromosomes. Similar significant correlations between intraspecific genome size variation in I. webberi and evapotranspiration and seed size were observed; genome size was larger in I. webberi populations closer to the species’ range center and smaller towards the margin. Relatively small genome sizes and their correlations with functional trait and energy availability indicate that genome size has adaptive significance for these desert-adapted species. Overall, the findings of these studies have advanced scientific knowledge on the eco-evolutionary processes in a range-restricted plant species in the Great Basin Desert, and provide useful information to design effective conservation programs

Management of protected areas in Sahel savannah ecoregion of Nigeria under the threat of desertification

This study was conducted to assess the challenges facing 8 selected protected areas in the Sahel Savannah ecoregion and proffer solutions to these challenges in order to ensure conservation and sustainability of Nigeria’s biodiversity. Primary data were collected from randomly-selected 120 staffs using questionnaire administration from 8 Forest Reserves within Borno and Yobe states of Nigeria. A high level of encroachment of all the studied protected areas was observed, which ranged from deforestation, overgrazing, poaching to converting protected areas into farmlands. Other notable challenges include poor staffing, inadequate equipment and funding. The respondents further reported that majority of the defaulters were farmers and local people in the area, involved in such practices for their survival in the wake of harsher climate and desert encroachment in the region. This paper calls for a revision of the Government Policy on Forestry in Nigeria to allow the people own and plant forests, implementation of community based forest resources management, provision of environment and user-friendly solar powered cooking stoves and sustainable farming systems such as crop rotation, intercropping, sustainable irrigation, organic farming and agroforestry. In addition, sources of income for the locals need to be diversified, such as honey bee production

Ecological studies on Aerangis biloba (Lindl.) Schltr. (Orchidaceae) in NACGRAB field gene bank, southwestern Nigeria

Aerangis biloba (Lindl.) Schltr. belongs to the family Orchidaceae, which is listed as threatened under the Appendix II of the CITES. This study was conducted to estimate the population and distribution of Aerangis biloba in the field by National Centre for Genetic Resources and Biotechnology (NACGRAB), Ibadan, southwestern Nigeria. Twenty five sample plots of 50m by 50m each along line transects were randomly chosen and studies were carried out on them. The results were correlated with the factors that affect the distribution and survival of A. biloba. A total of 129 specimens of A. biloba were observed within the study area, giving a population density of 5.16 orchids per m2. This indicates that the species is abundant in the sampled area, as a result of good population of the selected phorophytes. The analysis of the data indicated a high correlation between and among the plots (P=0.0003). A. biloba was observed only on nine trees among over 160 trees present in the sampling area, suggesting that these nine trees could act as phorophyte for A. biloba of which, Irvingia gabonensis and Irvingia wombulu harbored the highest number of orchids. The paper gives a synopsis of the economic and ecological significance of orchids. It also recommends controlled harvesting, reduced deforestation and establishment of orchid gardens as some of the effective ways of enhancing orchid conservation in Nigeria

Management of invasive plant species in Nigeria through economic exploitation: lessons from other countries

Invasive alien species, once they made entry into a region or country, often become difficult to eradicate and it appears that they have cometo stay. Worse still, their adverse effects on the native biodiversity are enormous and they are considered ecologically harmful. Agriculturaland economic losses to invasive species are comparatively high. Mechanical control is expensive and difficult in some terrains; chemicalcontrol is also expensive, requires constant application and has its environmental implications, while biological control is mirred with mixedfailures and successes. This paper reviewed that economic exploitation of some notorious invasive species in other countries – such asSudan, Ethiopia, India, Senegal, Mali and the Gambia – and how this had helped reduce the spread of these invasives and at the same time,became source of income to the poor people. It is believed that adopting this concept in Nigeria will create incentives for harvesting invasivespecies with more commitment, while it is an indirect way of controlling them. Furthermore, harvesting could be labour intensive, thuscreating jobs for people, while it provides additional means of income for rural people, which is a key adaptation strategy for climate change