Rapid Biodiversity Evaluation of the Arboreal Termites in Kano University of Science and Technology, Wudil, Nigeria

A rapid biodiversity evaluation of diversity of arboreal termites was carried out on the campus of Kano University of Science and Technology (KUST), Wudil, Nigeria. Three different trees namely, Mangifera indica, Azadirachta indica and Khaya senegalensis were selected from three different sites (campus new site, premises of administrative offices and the commercial area) in the campus and examined for termite activity such as mud tubes and nests. These were cut open with forceps to expose the termites. A soft brush was used for the collection of termite samples into a labeled sampling bottle containing 10% formalin solution. Sample collection was done during morning hours for one month at 7-day intervals A total of one hundred and twelve (112) individual termites were collected which belonged to five species namely Coptotermes sp., Microtermes sp., Odontotermes sp., Amitermes sp. and Nutitermes sp. Coptotermes sp. The total relative abundance of these species was 81.3% on trees and 80.4% sites, respectively. The diversity indices from the study showed the same species richness of termites on M. indica and K. senegalensis, while evenness was greater on K. senegalensis. Therefore, it had the greatest diversity of the termite fauna as compared to other trees. However, campus new site and commercial area also had the same species richness; although it was low in the premises of administrative offices. Evenness was greater in campus new site which had the greatest diversity. Coptotermes sp are insects of agricultural and economic importance and feed on dead wood; therefore, they are insect pests of these trees and other building structures erected on the campus.


Introduction
Termites are social insects which live in nests and form colonies. They belong to the phylum Arthropoda, class Insecta and order Isoptera. In tropical and subtropical regions, they are an important component of the ecosystem [1]. It has been speculated that termites have the greatest influence on the ecology of the world of any animal group, next to humans [2]. A normal colony of termites consists of nymphs, workers, soldiers and reproductive individuals and in some colonies, several egg laying queens are present [3]. They are decomposers and feed on dead plant materials, leaf litter, soil and animal dung [3]. To manage food sources and assess new habitats, termites exhibit a decentralized and self-organized system, swarm intelligence and cooperation among colony members [4]. The population of termites depends on environmental conditions such as food availability, soil texture, soil moisture, and soil temperature [5]. Their movement increases soil micropores through an increase in soil porosity, aeration and soil water permeability [6].
BioScientific Review Volume 2 Issue 2, 2020 Land use practices which include agricultural practices, industrialization and habitat fragmentation seriously affect the productivity and abundance of termites which results in the loss of biodiversity [5]. Termite species that construct their nest or mound on dead and growing trees are known as arboreal termites, while those which construct their nest or mound in soil are known as subterranean termites [5]. There are also dry wood and wet wood termites, respectively [2].
Termites possess the ability to cause damage to building materials, tarnish the color of structures, and destroy furniture among others; as such they are regarded as demolishers. Of the 2,600 known species of termites about 660 are found in Africa [7]. About 300 of these species have economic importance [8]. Macrotermes, Allodonterms, Odontotermes, Ancistrotermes, Amitermes, Pseudacanthotermes, Microtermes, Trinervitermes, and Macrotermes are some of the most economically important termite genera found in forests and agricultural areas [9]. In certain ecosystems such as the African savanna, termites may be the single most prominent organism involved in biodegrading the nutrients found within dead plant matter. There is extensive contribution of termites in damaging buildings as wood is the best of all foods that termites consume; termites also feed on other materials such as dry grass, fallen leaves, humusrich soil, and dried animal dung [2]. The diversity and abundance of termite species have been well documented in USA, Canada, Australia, UK, India, Asia, Cameroon and South Africa but not in Nigeria [10]. In the northwestern part of Nigeria in general and in Kano State in particular, there is little or no information available about the biodiversity of termites. Therefore, the current study is aimed at determining the diversity of termite species inhabiting selected trees in KUST, Wudil campus, considering the importance of these trees in the ecosystem.

Study Area / Layout
The study was conducted in the campus of Kano University of Science and Technology (KUST),Wudil, Nigeria which is located approximately between longitude 8° 45'E and 8° 57'E and latitude 11° 37'N and 11° 56'N. Three different sites within the campus were selected and investigated for termite diversity, which included campus new site (longitude 8.860460°E: latitude 11.808110°N), premises of administrative offices (longitude 8.851266°E: latitude 11.803913°N) and the commercial area (longitude 8.853255°E: latitude 11.804021°N). These were labeled as site A, B and C, respectively. At each site, three different trees were selected for termite sample collection. They included M. indica (Mango), A. indica (Neem) and K. senegalensis (Mahogany).

Sample Collection and Identification
Termite samples were collected following the procedure described by Ugbomeh et al. [11] with slight modification. Sampling was done in the morning for one month at 7-day intervals, from 19 th January, 2020 to 29 th February, 2020. A total of eighty-four trees (twenty-eight each of M. indica, A. indica and K. senegalensis) from sites A, B, and C were randomly examined for termite activity represented by either mud tubes or nests which indicate infestation by termites. These were opened with forceps to expose the insects. Using a soft brush, termite samples were collected into labeled Department of Life Sciences Volume 2 Issue 2, 2020 sampling bottles containing 10% formalin solution and trees were marked with paint for the ease of recognition. The insects collected were taken to laboratory for identification.
Termites were examined with hand lens and dissecting microscope. Identification was conducted to genus level with the aid of the guides by Donovan et al. [12] and Kambhampati and Eggleton [13]. Identification was based on morphological features such as body color, shape of head and mandibles, number of segments on abdomen and antenna. The identified species were counted and their relative abundance was calculated.

Data Analysis
The data collected were subjected to diversity analysis and abundance models separately for trees and sites. Diversity indices and species richness analysis was conducted with BioDiversity Professional Ecological Statistical software (Version 2). Table 1 shows the relative abundance of termite species present on selected trees in KUST, Wudil campus, Nigeria abundant species of termite on both

Results
The Coptotermes (81.3%) was the most trees with a higher number of individuals recorded. This was followed by Odontotermes (8.4%) and Macrotermes (5.4%), respectively. The species of termites least found on trees were Nasutitermes (1.79%) and Amitermes (3.57%), respectively. Table 2 shows the diversity indices and models of fit for the termite species inhabiting sampled trees in KUST, Wudil campus. The results showed that species richness was the same on two (M. indica and K. senegalensis) of the three trees. The Fisher alpha and Margalef indices were similar for these trees, while the Chao-1 index was greater for K. senegalensis as compared to M. indica. Also K. senegalensis had a greater Simpson index than M. indica. The Shannon index of these trees was equal and the Berger-Paker index of the trees was similar. Evenness was greater in K. senegalensis than M. indica. A. indica had a higher species richness and Fisher alpha indices than the other two trees, while its Margalef index was low. The Chao-1 index of A. indica was below that of K. senegalensis. Shannon and Berger-Paker indices were greater than that of other trees, while the Simpson index was similar to K. senegalensis. The log series and broken stick models poorly fitted into the data.  Table 3 shows the relative abundance of termite species from three different sites irrespective of the trees in KUST, Wudil campus. Coptotermes (80.4%) was the most abundant species at both sites. It was followed by Odontotermes (8.9%) and Amitermes (5.4%), respectively. The least found were Nasutitermes (1.8%) and Macrotermes (3.6%). Coptotermes had the highest relative abundance (92.9%) at site B, while Odontotermes (17.6%), Macrotermes (5.9%) and Nasutitermes (2.9%) were most abundant at site A. Amitermes (11.1%) had the highest relative abundance at site C. The value of p in Chi square goodness of fit test is 0.05. Table 4 shows the diversity indices and models best fit for termite species from different sites at KUST, Wudil campus.
The results showed that the species richness of termites was the same at two (site A and site C) of the three sites. The Fisher alpha and Margalef indices were greater for site A, while Chao-1 index was greater for site C as compared to site A. Simpson, Shannon, and Berger-Parker indices were greater for site A. Evenness was also greater for site A but dominance was less as compared to site C. At site B, species richness was the lowest and Chao-1 index of site B was greater as compared to site A. Although dominance was greater than the other two sites, evenness and all other indices were the lowest. The log series and broken stick models poorly fitted into the data from the respective sites.

Discussion
A total of one hundred and twelve (112) individual termites were collected for the current study. This is similar to the findings of study by Nwosu and Akor [14], who collected 185 individual termites in Naka, Benue, Nigeria. Five species of termites were documented from the study sites which were among the species that attack trees and woods. This discovery corresponds to the findings of Ogedegbe and Eloka [3], who reported that five of the seven species of termites recorded on farmlands in Edo state, Nigeria attack trees and build their nests on them.
Coptotermes sp. were found to be the most abundant termite species, both from the sites and on the trees studied.
On the contrary, Wekhe et al. [5] stated that Amitermes sp. was the most abundant subterranean termite species at River State University campus. However, the abundance of Coptotermes could be due to the fact that they were the insect pest of the studied trees as reported by Bong et al. [15], who found Coptotermes as the insect pest of oil palm plantation in Malaysia. According to Cranshaw and Redak [2], subterranean termites never expose themselves aboveground during forage because they are very sensitive to drying, they may build shelter tubes from soil and bits of debris cemented together with feces and secretions to reach the wood beyond a barrier. All the five species of termites were recorded as nested on the trees studied. In the same vein, Kemabonta and Balogun [16] reported Coptotermes, Amitermes, and Nasutitermes among wood nesting species of termites at University of Lagos. Site A with lower extrapolated species richness according to Chao-1 index and lower dominance had all other indices greater than that of other sites; hence the termite species were more diverse there.
This was followed by site C and the least diverse was site B, despite the fact that the site had more individuals and estimated species richness than other sites.
For both trees and sites, the unsatisfactory fit of the model for log series predicted too many rare species of termites, while broken stick predicted fewer rare species of termites than were recorded.

Conclusion
The abundantly found arboreal termites on KUST, Wudil campus are mud tube Coptotermes sp. They are found on all the trees selected for the study. Therefore, they are considered as insect pest of these trees. Termite species prefer inhabiting K. senegalensis mainly because these species remain undisturbed on this tree as compared to other trees. Moreover, campus new site (site A) has greater termite diversity on trees as the area has some ongoing constructions.