Preliminary Survey on The Termite Mounds, Their Interior Geometrics and The Termite Prevention from Infrastructural Construction at New Site of Ndola International Airport in Zambia

An ecological study was conducted on termites located at the new site of Ndola International Airport in Zambia. The aim of this study was: (a) to assess the distribution pattern of different sizes of termite mounds located at the site, (b) to investigate the interior geometrics of termite mounds, (c) to determine the colony sizes of termites per each mound found at the site and (d) to provide technical expertise on the different termite preventive methods used on new buildings. Methods: Using an aero-drone fitted with a camera, aerial surveys were conducted to capture and evaluate the spread of differently sized mounds at the site. Mathematical models were used to calculate the volume and number of nests contained in each mound. The colony sizes were captured and recorded per each mound. Analysis: Multivariate statistical analyses were performed using SPSS, to compute a two way ANOVA table for comparison of p-values involving the colony sizes and the volumes of nests for small and big mounds. The ratios affecting these volumes were also calculated. Results: The total of 1,880 termite mounds was captured spreading at an average of 14 mounds/ 1km. Results further showed that 65% of total mounds were actively housing termites while 32% were virtually deserted. The 3% balance of mounds were occupied by rodents, ants and snakes, respectively. Progression on the volume of nests in bigger and smaller mounds, significantly tallied with the size of mound at p < 0.0121 and p < 0.0346, respectively. Similarly, the colony size of termites in small and larger mounds was also significant at p < 0.002 and p < 0.001, respectively. The nest volume ratios of small, medium and larger mounds were also markedly increasing with the size of mound at 1:8.7-small, 1:32.8 medium and 1:1, 098.6-large, respectively. Conclusion: Not every existing termite mound is occupied by termites; the size of nest was directly related to the size of mound; the size of colony concurrently increased with that of the volume of nest. This study unravels some intriguing and conflicting suggestions that smaller mounds can still have larger colonies underground and vice versa. Furthermore, this study is the first in Zambia to combine the concepts of termite habitat geometrics and infrastructural protection. DOI : 10.14302/issn.2637-6075.jpae-17-1868 Freely Available Online www.openaccesspub.org JPAE CC-license DOI : 10.14302/issn.2637-6075.jpae-17-1868 Vol-1 Issue 1 Pg. no.– 44 Introduction In the Agricultural industry, termites are regarded essential insects in fixing the soil ecosystems by improving the soil pH, organic carbon content, water content and porosity [1,2,3]. However, termites are also known in causing detrimental effects in agriculture by destroying a number of food crops like maize cassava etc. [4,5,6,7]. Furthermore, termite activities can still be a menace in the urban set up where they are associated with destroying a variety of components from unprotected buildings [8,9,10,11]. These damages caused by termites on buildings are of great economic importance for home owners because the integrity of infested buildings get compromised, resulting into their loss in value [12,13,14,15]. To date, it is estimated that billions of dollars are spent annually on the control of termites worldwide [16,17,18]. In Australia and China, termite infestations are widespread, with an estimation of 20% of Australian homes and up to 90% of Chinese homes, south of the Yangtze River being affected by termite damage [19,20,21]. Termite infestation is also a major problem to urban buildings in many tropical countries including Malaysia [22]. In particular, the termite damage to buildings in tropical countries is of serious concern, with losses sometimes approximated to 100% [23]. However, there is paucity of data documented on the termite damage to buildings in the sub-Saharan countries [14]. Of late, the available anecdotal data in Zambia, attest to a wide spread of termite infestations recorded on buildings including: houses, offices, libraries, gymnasium, warehouses, Bank, Universities and some Airports. Despite the alarming incidences on termite damage to infrastructure in Zambia, there is very little knowledge on the preventive measures to both the general communities and the building constructors. In most cases, no one seems bothered, even when severe termite damages are observed on important buildings in the country. Until recently, chemical control methods, including organochlorines (OC) and organophosphates (OP) have been world-widely used on termite attacks during the past 30-35 years, with the OP subsequently replacing the OC [24,25]. Essentially, organochloride pesticides i.e. dieldrin, dichlorodiphenyltrichlothane (DDT), aldrin, endrin, lindane, heptachlor, etc. were used as pesticides in Australia and many countries for a number of decades but were later deregistered when they were observed to be persistent organic pollutants (POPs) [26,27]. In 2001, the USA manufactured organophosphates (OP) pesticides i.e. parathion, malathion, diazinon, fethion, diclorvos, etc. were also banned by the Environmental Protection Agency (EPA) due to similar reasons of POPs [26,14]. In recent years, the enhanced manufacturing of pyrethroid pesticides i.e. thiodicarb, fipronil, thiamethoxam, tebufenozide, methomyl, lambda, etc. which are more specific in action and friendly to human and environment [28]. Among the over 700 banned or deregistered OC and OP pesticides, few are still being used in sub-Saharan Africa, Asia and USA, on special order and closely monitored in use by regulatory bodies [29]. Ratios for water to chemical concentration of these pesticides vary and are always provided by the company manufacturing the chemical brand. To achieve better results, instructions on chemical to water ratios should be followed accordingly. While most of chemicals can be used in contact treatment, others may also be used in fumigation methods [28]. However, the physical control method might not always be used as conventional Corresponding Author: Alfred M. Sichilima, Department of Biological Sciences, School of Mathematics and Natural Sciences, Copperbelt University, P.O. Box 21692, Kitwe, Zambia. Email: alfred.sichilima@cbu.ac.zm


Introduction
In the Agricultural industry, termites are regarded essential insects in fixing the soil ecosystems by improving the soil pH, organic carbon content, water content and porosity [1,2,3]. However, termites are also known in causing detrimental effects in agriculture by destroying a number of food crops like maize cassava etc. [4,5,6,7]. Furthermore, termite activities can still be a menace in the urban set up where they are associated with destroying a variety of components from unprotected buildings [8,9,10,11]. These damages caused by termites on buildings are of great economic importance for home owners because the integrity of infested buildings get compromised, resulting into their loss in value [12,13,14,15]. To date, it is estimated that billions of dollars are spent annually on the control of termites worldwide [16,17,18].
In Australia and China, termite infestations are widespread, with an estimation of 20% of Australian homes and up to 90% of Chinese homes, south of the Yangtze River being affected by termite damage [19,20,21]. Termite infestation is also a major problem to urban buildings in many tropical countries including Malaysia [22]. In particular, the termite damage to buildings in tropical countries is of serious concern, with losses sometimes approximated to 100% [23].
However, there is paucity of data documented on the termite damage to buildings in the sub-Saharan countries [14]. Of late, the available anecdotal data in replacing the OC [24,25]. Essentially, organochloride pesticides i.e. dieldrin, dichlorodiphenyltrichlothane (DDT), aldrin, endrin, lindane, heptachlor, etc. were used as pesticides in Australia and many countries for a number of decades but were later deregistered when they were observed to be persistent organic pollutants (POPs) [26,27]. In 2001, the USA manufactured organophosphates (OP) pesticides i.e. parathion, malathion, diazinon, fethion, diclorvos, etc. were also banned by the Environmental Protection Agency (EPA) due to similar reasons of POPs [26,14]. In recent years, the enhanced manufacturing of pyrethroid pesticides i.e. thiodicarb, fipronil, thiamethoxam, tebufenozide, methomyl, lambda, etc. which are more specific in action and friendly to human and environment [28].
Among the over 700 banned or deregistered OC and OP pesticides, few are still being used in sub-Saharan Africa, Asia and USA, on special order and closely monitored in use by regulatory bodies [29]. Ratios for water to chemical concentration of these pesticides vary and are always provided by the company manufacturing the chemical brand. To achieve better results, instructions on chemical to water ratios should be followed accordingly. While most of chemicals can be used in contact treatment, others may also be used in fumigation methods [28]. However, the physical control method might not always be used as conventional  [28].
In some cases, these agents are released into the soil or injected into the above ground termite galleries [14,30].
With the new and safer methods of termite control being introduced, more research is needed in order to compare and determine advantages and limitations [18]. were conducted, using an aero-drone fitted with a camera, and operated with a high-tech remote control system from the ground surface (Fig. 2). Aerial surveys were constantly conducted along the 30m width, at the lower altitudes ranging from 45-55m above the ground, in order to clearly capture different mounds ( Fig. 2 & 3).
To enable better assessment of geometrics, mounds were also classified into small, medium and larger ( Fig. 4). The average number of mounds per 1 km 2 were calculated.   Characteristically, fipronil is much more toxic to insects than to humans and animals. The liquid form was better used in tankers to spray a wider area while the dust was more of spot application. The dosage in terms of ratio of concentrations between chemical: water were followed according to instructions provided by the company that produced chemicals.

Geometric Calculations, Colony Size Assessment and Sample Collection
The mounds were carefully opened up so as not to disturb the set-up and arrangement of nests and tunnels leading to the nest. Parameters of width and height of mound were recorded. The number of tunnels were counted so that their width and depth in cm up to the nest was recorded. The width and height of nest were also recorded. These dimensions were eventually used to calculate the volume of each nest and mound at the site (Fig. 9). The colony size was also assessed for each nest. Samples of termites were collected from each nest for further identification (Fig. 10). The manually calculated volumes and colony sizes were also initially verified using the HC-01 visual termite detector.

Termite Treatment and their Ecological Tenacity in Securing Passage
The existence of both the mound building and the mound-less subterranean termites has enabled civil engineers to come up with new and more sophisticated methods for both identifying nests and in preventing termites from entry into buildings. In most cases, engineers have partnered with entomologists so as to jointly address the termite situation at the construction site, especially for bigger projects like constructing the International Airport. According to Peterson [36], the best time to prevent termite problems on the property is at the construction stage. While the nests for most mound building termites are located within mounds or few meters below the mound, the nests of subterranean termites can occur anywhere below the tree or where the stump of the tree is located [15] or below any flat surface area of land. Nests of these termites might also be located somewhere below the concretes of some houses.
For the effective termite prevention from the house being constructed, pretreatment is vital in following four areas: (i) Treatment of the entire soil  and larger mounds was significant at p < 0.002 and p < 0.001, respectively (Fig. 14). The nest volume ratios of small, medium and large mounds were also markedly increasing with the size of mound at 1:8.7-small, 1:32.8 medium and 1:1,098.6-large, respectively (Fig. 15). On the other hand, results on the trials conducted on the efficacy of fipronil (5% SC) showed that the chemical was 100% efficient in killing termites, within 10-15 days from the first treatment date ( Table 2).

Discussion
It was evident from this study that only 65% of 1,889 mounds were actively housing termites while 32% of these mounds were seemingly deserted. Furthermore, out of 56 mounds that contained various occupants other than termites, 29 mounds contained ants while 21 mounds were occupied by rodents while 6 mounds housed snakes which were either in singles or several of them, suggesting that snakes and rodents can live and reproduce in termite mounds (Fig. 12). It was unclear however, whether these intruders that were found in termite mounds, occupied them when termites had already deserted them or they entered mounds on a hunting mission, to capture termites for food and after they overpowered the occupants, they fed on them to the extinction of the entire colony and eventually decided to take over their habitat nest and tunnels after a fierce conquest battle.
It was unclear however, whether the 32% of mounds that were detected without termites had been indeed deserted or rather some of them had nests deeply located beyond the detection capability of the instrument we used. According to Lee et al., [37], and   where it was reported that some termite mounds were found occupied by ants, rodents and snakes.