People, Planet, 4(3), 201–213

 Journal

 Assessing Climate Risk To Support Urban Forests In A Changing Climate. People, Planet

 Esperon-Rodriguez, M., Rymer, P. D., Power, S. A., Barton, D. N., Cariñanos, P., Dobbs, C., Eleuterio, A. A., Escobedo, F. J., Hauer, R., Hermy, M., Jahani, A., Onyekwelu, J. C., Östberg, J., Pataki, D., Randrup, T. B., Rasmussen, T., Roman, L. A., Russo, A., Shackleton, C., … Tjoelker, M. G.

 2022

The management of urban forests is a key element of resilience planning in cities across the globe. Urban forests provide ecosystem services as well as other naturebased solutions to 4.2 billion people living in cities. However, to continue to do so effectively, urban forests need to be able to thrive in an increasingly changing climate. Trees in cities are vulnerable to extreme heat and drought events, which are predicted to increase in frequency and severity under climate change. Knowledge of species' vulnerability to climate change, therefore, is crucial to ensure provision of desired ecosystem benefits, improve species selection, maintain tree growth and reduce tree mortality, dieback and stress in urban forests. Yet, systematic assessments of causes of tree dieback and mortality in urban environments are rare. We reviewed the state of knowledge of tree mortality in urban forests globally, finding very few frameworks that enable detection of climate change impacts on urban forests and no long-term studies assessing climate change as a direct driver of urban tree dieback and mortality. The effects of climate change on urban forests remain poorly understood and quantified, constraining the ability of governments to incorporate climate change resilience into urban forestry planning. 

 Urban Ecosystems 25:165–178

 Journal

 Assessing The Conservation Status, Biodiversity Potentials And Economic Contribution Of Urban Tree Ecosystems In Nigerian Cities.

 Agbelade, A.D. And Onyekwelu, J.C., John, A.A. Adedayo, J. And Alabi, T.

 2022

We investigated conservation status, biodiversity potentials and economic contribution of urban tree Ecosystems in Nigerian cities. A total of 32 families were encountered respectively in Makurdi (17), Ilorin (18) and Lokoja (25) urban forests. The diversity index, richness and evenness of the tree species were in the order Ilorin>Lokoja>Makurdi urban forests and decreased as the population of the city increased, suggesting that the urban forests and trees depends on city infrastructure development. About 32% of tree species in the three cities are threatened tree species in Nigeria and based on the IUCN red list. This situation therefore calls for urgent conservation measures. Moreover, results showed a general increasing trend in Normalized Different Vegetation Index (NDVI) value between year 2000 and 2018 for the vegetation cover in each city. 

 International Journal Of The Commons

 Journal

 Drivers Of Biodiversity Conservation In Sacred Groves: A Comparative Study Of Three Sacred Groves In Southwestern Nigeria.

 Adeyanju, S.O., Bulkan, J., Onyekwelu, J.C., St-Laurent, G.P., Kozak, R., Sunderland, T And Stimm, B.

 2022

Nil 

 Forest And Forest Products Journal (Accepted For Publication)

 Journal

 Proximate, Antioxidant Compositions And Oil Yield Of Allanblackia Floribunda Seeds And Characterization Of Its Oil

 Onyekwelu, J.C. And Ayeni, A.A

 2022

Proximate and antioxidant compositions, yield and characterization of Allanblackia floribunda seed oil were investigated using appropriate analytical methods. Oil extraction was done with petroleum ether as a solvent for Soxhlet extraction apparatus. Carbohydrate (33.69%), fat (46.98%) and crude fiber (8.79%) contents of A. floribunda seed were high while crude protein (9.05%) content was moderate. Moisture (4.35%), ash (1.49%) and all anti-nutrient contents of the seed were low, implying that A. floribunda seed has high nutritional compositions and that its consumption would not be detrimental to human health. The seed has high antioxidant compositions with mean phenol, flavonoid, FRAP, ABTS, DPPH and Fe2+ of 9.75mg.g-1, 17.73mg.g-1, 88.4mg.g-1, 85.5 mMol/g, 29.54% and 20.39%, respectively, suggesting that the seed is a potential source of natural antioxidants and can be used as supplement in food and nutritional drinks. Mean oil yield was 46.5%, revealing that it is a high oil-yielding seed. The oil is suitable for human consumption due to its peroxide value (2.20 mEqO2/kg of oil). The FFA of 1.55mg NaOH/g implies good quality oil that would not easily go rancid, with long shelf life. To harness the commercial potentials of A. floribunda seed oil, domestication of the species is recommended. 

 Journal Of Tropical Forest Science (Under Review)

 Journal

 Conservation Potentials, Tree Species Diversity, Distribution And Structure Of Sacred Forests In Southwestern, Nigeria

 Onyekwelu, J.C., Tolorunju, M.S., Agbelade, A.D., Lawal, A., Stimm, B. And Mosandl, R.

 2022

Though sacred groves were not originally established for biodiversity conservation purposes, they have contributed largely to biodiversity conservation. We investigated the distribution of sacred groves in South-western Nigeria and examined their biodiversity conservation potentials. Four sacred groves (Osun-Osogbo, Igbo-Olodumare, Idanre hills and Ogun-Onire) were selected for this study. Data were collected from 32 temporary sample plots of 20 m x 40 m. Nineteen sacred groves were identified across south-western Nigeria. A total of 37 families were enumerated within the four groves, with 32, 26, 22 and 22 families occurring in Ogun-Onire, Idanre Hills, Osun-Osogbo and Igbo-Olodumare, respectively. A pooled total of 141 tree species (range: 41 to 85 per grove) were encountered in the four sacred groves, with Ogun-Onire having a significantly higher number of species than the other groves. Tree density ranged from 1427 ha-1 to 4825 ha-1. Shannon-Wiener diversity index (range: 2.63 to 3.55) was significantly different in the four groves, with Igbo-Olodumare and Ogun-Onire having the lowest and highest values, respectively. When compared to the biodiversity indices of some tropical rainforests, our results indicated that sacred groves have high potentials for biodiversity conservation and thus could serve as reservoir of biodiversity. 

 Southern Forests: A Journal Of Forest Science (Under Review)

 Journal

 Role Of Sacred Groves In Southwestern Nigeria In Biodiversity Conservation, Biomass Production And Carbon Stock Accumulation

 Onyekwelu, J.C., Agbelade, A.D., Stimm, B. And Mosandl, R.

 2022

We collected data from four sacred groves (Osun-Osogbo, Igbo-Olodumare, Idanre Hills and Ogun-Onire) in southwestern Nigeria to investigate their role in biodiversity conservation, biomass and carbon stock accumulations. 

 Academia Letters, Article 635

 Journal

 Can The Fear Of The Gods Sustain Biodiversity Conservation In Sacred Groves?

 Onyekwelu, J.C.

 2021

Globally, indigenous people have rich traditions of nature conservation through socio-religious and socio-cultural use, respect and protection for natural resources, aided by belief that god(s) live in the forest. The people have relied on their gods and local knowledge to protect their forests. Traditional conservation systems (e.g. sacred groves) have contributed to biodiversity conservation. Today, they are noted to habour rich biodiversity and refuge for endangered and endemic species. In sacred grove species protection is mostly through rules, taboos or dedicating the forest to god(s). Thus, the fear and respect of god(s), fear of negative consequences for violation of rules/taboos, etc, serve as motivations for conserving sacred groves. The extent to which the fear of god(s) can sustain biodiversity conservation remains uncertain. The changing belief systems in most communities suggest that the fear of gods may be insufficient in securing the important biodiversity conservation function of sacred groves in future. This calls for alternative strategy(ies) to compliment the socio-religious systems of sacred grove. 

 Https://doi.org/10.1016/j.conbuildmat.2021.123123

 Journal

 Mechanical Properties Of Gmelina Arborea For Engineering Design.

 Iwuoha, S.E., Seim, W. And Onyekwelu, J.C.

 2021

Gmelina arborea is a fast-growing hardwood species whose material properties according to available data have never been properly studied. This work presents an extensive study on the process of acquiring, preparing, testing and all analyses involved in determining the mechanical properties of Gmelina arborea for the design of load bearing structures. Samples obtained from 25-year-old Gmelina trees harvested from a plantation in South Western Nigeria, were transported to the laboratory of the Department of Timber Structures and Building Rehabilitation, University of Kassel where they were seasoned, prepared, and tested in accordance with European and German standards, afterwards, detailed statistical analyses were carried out on the experimental data. While the distribution functions in the Joint committee for Structural Safety model code were validated for some material properties, they could not be validated for others. The material properties of the hardwood species were found to compare well with those of European softwood species and shows good potentials for use as a construction material. 

 Tropical Ecology (2021)

 Journal

 Understory Species Diversity, Regeneration And Recruitment Potential Of Sacred Groves In South West Nigeria.

 Onyekwelu, J.C., Lawal, A., Mosandl, R.,Stimm, B. And Agbelade, A.D.

 2021

Nil 

 Forstliche Forschungsberichte 219, Munich, Germany, Pp 132 - 148

 Others

 Significance Of Traditional Forest Management System To Biodiversity Conservation And Ecosystem Services Provision: Case Study Of Osun-Osogbo Sacred Grove, Nigeria.

 Onyekwelu, J.C.

 2021

This study investigated and compared the biodiversity status of sacred grove, primary and degraded forests. Osun-Osogbo sacred grove, two primary and two degraded forests were involved. Osun-Osogbo sacred grove had the highest species richness, Shannon-Wiener diversity index, regeneration richness and high species evenness. The better diversity indices of Osun-Osogbo grove compared to those of primary and degraded forests are indications of its importance in biodiversity conservation. The preservation of the sacred grove was secured through belief and fear of deity, preservation of culture, place of worship, etc. Some ecosystem services provided by sacred grove include: healing, protection and peace, tourism, employment provision, spiritual worship, revenue generation, etc.