Article

Potential Impact of Climate Change on Termite Distribution in Africa

Authors:
To read the full-text of this research, you can request a copy directly from the author.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the author.

... Studies have shown that an average annual rainfall and temperature below 100 cm and 27 C, respectively, promote the survival and catastrophic impacts of the pest (Atu 1993;Richard et al. 2006;Belyaeva and Tiunov 2010). Though termites have been reported to be present throughout the year in most tropical countries of Africa (Wood 1995), their agricultural and economic damage tend to be exacerbated during periods of low rainfall (Ahmed et al. 2011). In the study conducted on the potential impact of climate change on termite distribution in Southern Zambia, Ahmed et al. (2011) found that after a drought, the number of pestiferous termite species increased drastically. ...
... Though termites have been reported to be present throughout the year in most tropical countries of Africa (Wood 1995), their agricultural and economic damage tend to be exacerbated during periods of low rainfall (Ahmed et al. 2011). In the study conducted on the potential impact of climate change on termite distribution in Southern Zambia, Ahmed et al. (2011) found that after a drought, the number of pestiferous termite species increased drastically. Similarly, another study, performed in Uganda by Pomeroy (1976), demonstrated that the distribution of termites' mounds was significantly correlated with temperature and that large termite mounds were absent in areas of lower temperature and high rainfall. ...
... For example, in the last two to three decades, drought associated with El Niño episodes has become more intense and widespread in Africa (Harrington and Stork 1995). Many studies have previously established strong nexus among climate change, termites invasion, and damage to agricultural resources (Jones 1990;Kemp 1955;Logan et al. 1990;Nkunika 1998;Bignell and Eggleton 2000;Eggleton et al. 2002;Ahmed and French 2008;Ahmed et al. 2011;Beaudrot et al. 2011;Rouland-Lefèvre 2011;Buczkowski and Bertelsmeier 2017). ...
Chapter
Full-text available
Climate change is a global issue threatening food security, environmental safety, and human health in tropical and developing countries where people depend mainly on agriculture for their livelihood. Nigeria ranks among the top in the global yam production. It has the largest population in Africa and has been able to secure food for its growing population through food crops especially yam. Unfortunately, the recent increase in termites’ colonies due to climate change threatens yam yield. Besides harming man and environment, pesticides are expensive and not easily accessible to control the pests. This prompted a study which aimed at applying a biotrado-cultural approach in controlling the termites, as well as improving soil chemical properties and yam production. The study hypothesized that Chromolaena odorata and Elaeis guineensis sludge improved soil nutrient and yam yield and consequently decreased termites’ outbreak. In a randomized design experiment of five blocks and five replicates, five different treatments including unmanaged (UM), Vernonia amygdalina (VA), Chromolaena odorata (CO), Elaeis guineensis (EG) liquid sludge, and fipronil (FP) were applied in termites-infested agricultural soil. Data were collected and measured on the responses of soil chemical properties, termites, and yam yield to treatments using one-way ANOVA, regression, and multivariate analyses. The result showed that Chromolaena odorata (CO) and EG treatments were the best treatments for controlling termites and increase yam production. Termites were successfully controlled in VA and FP treatments, but the control was not commensurate with yam production. The experiment needs to be extended to other locations in the study region. It also requires an intensive and long-term investigation in order to thoroughly understand (i) the influence of climate change on the termites’ outbreak, (ii) the extent of termite damage to the crops, (iii) the impacts of climate change and variability on yam yields, (iii) the agricultural and economic benefits of the applied treatments, and (iv) the ecological and human health safety of the treatments.
... Studies have shown that an average annual rainfall and temperature below 100 cm and 27 C, respectively, promote the survival and catastrophic impacts of the pest (Atu 1993;Richard et al. 2006;Belyaeva and Tiunov 2010). Though termites have been reported to be present throughout the year in most tropical countries of Africa (Wood 1995), their agricultural and economic damage tend to be exacerbated during periods of low rainfall (Ahmed et al. 2011). In the study conducted on the potential impact of climate change on termite distribution in Southern Zambia, Ahmed et al. (2011) found that after a drought, the number of pestiferous termite species increased drastically. ...
... Though termites have been reported to be present throughout the year in most tropical countries of Africa (Wood 1995), their agricultural and economic damage tend to be exacerbated during periods of low rainfall (Ahmed et al. 2011). In the study conducted on the potential impact of climate change on termite distribution in Southern Zambia, Ahmed et al. (2011) found that after a drought, the number of pestiferous termite species increased drastically. Similarly, another study, performed in Uganda by Pomeroy (1976), demonstrated that the distribution of termites' mounds was significantly correlated with temperature and that large termite mounds were absent in areas of lower temperature and high rainfall. ...
... For example, in the last two to three decades, drought associated with El Niño episodes has become more intense and widespread in Africa (Harrington and Stork 1995). Many studies have previously established strong nexus among climate change, termites invasion, and damage to agricultural resources (Jones 1990;Kemp 1955;Logan et al. 1990;Nkunika 1998;Bignell and Eggleton 2000;Eggleton et al. 2002;Ahmed and French 2008;Ahmed et al. 2011;Beaudrot et al. 2011;Rouland-Lefèvre 2011;Buczkowski and Bertelsmeier 2017). ...
Chapter
Full-text available
Climate change is a global issue threatening food security, environmental safety, and human health in tropical and developing countries where people depend mainly on agriculture for their livelihood. Nigeria ranks among the top in the global yam production. It has the largest population in Africa and has been able to secure food for its growing population through food crops especially yam. Unfortunately, the recent increase in termites’ colonies due to climate change threatens yam yield. Besides harming man and environment, pesticides are expensive and not easily accessible to control the pests. This prompted a study which aimed at applying a biotrado-cultural approach in controlling the termites, as well as improving soil chemical properties and yam production. The study hypothesized that Chromolaena odorata and Elaeis guineensis sludge improved soil nutrient and yam yield and consequently decreased termites’ outbreak. In a randomized design experiment of five blocks and five replicates, five different treatments including unmanaged (UM), Vernonia amygdalina (VA), Chromolaena odorata (CO), Elaeis guineensis (EG) liquid sludge, and fipronil (FP) were applied in termites-infested agricultural soil. Data were collected and measured on the responses of soil chemical properties, termites, and yam yield to treatments using one-way ANOVA, regression, and multivariate analyses. The result showed that Chromolaena odorata (CO) and EG treatments were the best treatments for controlling termites and increase yam production. Termites were successfully controlled in VA and FP treatments, but the control was not commensurate with yam production. The experiment needs to be extended to other locations in the study region. It also requires an intensive and long-term investigation in order to thoroughly understand (i) the influence of climate change on the termites’ outbreak, (ii) the extent of termite damage to the crops, (iii) the impacts of climate change and variability on yam yields, (iii) the agricultural and economic benefits of the applied treatments, and (iv) the ecological and human health safety of the treatments.
... Termites are grouped into seven families and 15 subfamilies [11], 281 genera [12], and over 3500 species identified worldwide [13]. Africa has the richest intercontinental diversity of termites with over 70% of all the identified species [14]. The family Termitidae alone comprises more than 664 African species grouped in four subfamilies: Apicotermitinae with 70 species [15], Termitinae with 272 species [16], Macrotermitinae with 165 African fungus-growing termites [17], and Nasutitermitinae with 56 species [18]. ...
... The family Termitidae alone comprises more than 664 African species grouped in four subfamilies: Apicotermitinae with 70 species [15], Termitinae with 272 species [16], Macrotermitinae with 165 African fungus-growing termites [17], and Nasutitermitinae with 56 species [18]. The total number of species of termites in the four subfamilies may surpass 90% of the world's known termite species [14]. These authors reported species richness and diversity (see below the formulas for their calculation) as a result of the friendly climatic conditions in Africa, and that, dry climate is a factor contributing for low numbers of termite species in some regions of the world. ...
... These authors reported species richness and diversity (see below the formulas for their calculation) as a result of the friendly climatic conditions in Africa, and that, dry climate is a factor contributing for low numbers of termite species in some regions of the world. For example, termite species diversity is lower in Northern Africa compared to Eastern, Western, and Southern regions of the continent [14]. Kemabonta et al. [19] also reported that termites are prominent in both tropical and subtropical ecosystems, but highest diversity is observed in tropical forests where they build very complex communities [16]. ...
... Some authors observed that termites attack bone material, mainly during dry seasons (Thorne & Kimsey, 1983). In addition, the entomological literature highlights the fact that termites have much more intense feeding behaviours on wood during periods of drought (Ahmed et al., 2011;Wightman, 1989Wightman, , 1991). This behaviour is explained by their constant search for moisture. ...
... Our aforementioned observations of termite feeding behaviour and nutritional requirements lend further support to our hypothesis regarding the nature of OH1's burial. In 90% of cases, subterranean termites build their nests near tree stumps and/or piles of decaying wood (Ahmed et al., 2011;Su & Bardunias, 2005), in other words, close to their main food source. However, in the case of OH1, to prove the presence of a plant cover or to estimate the vegetal concentration in the vicinity of a burial based on termite activity, additional experimentation would be needed to determine the level of attraction of termites to plant resources in contrast to fresh bones. ...
... However, in the case of OH1, to prove the presence of a plant cover or to estimate the vegetal concentration in the vicinity of a burial based on termite activity, additional experimentation would be needed to determine the level of attraction of termites to plant resources in contrast to fresh bones. Finally, previous researchers have argued that osteophageous behaviour in termites may reflect seasonal and nutritional needs during dry periods (Ahmed et al., 2011;Prestes et al., 2014;Queiroz et al., 2016;Thorne & Kimsey, 1983;Wightman, 1989Wightman, , 1991Wood & Johnson, 1978). Therefore, the extensive destruction of the OH1 skeleton also could be due to an extreme aridity period that would have intensified termites' osteophagic activities. ...
Article
Full-text available
This paper presents a case study of the Late Pleistocene skeletal remains of Olduvai Hominid 1, which were unearthed in Tanzania. Excavated in 1913, this fossil shows severe damage due to subterranean termites (Insecta: Isoptera). By combining methods to quantify and locate traces on the skeleton with the study of the different taphonomic processes that altered the deposit, we demonstrate a non-arbitrary pattern of termite alteration of the skeletal remains. These results shed new light on the possibility to reconstruct the original position of a skeleton in a deposit and the potential to infer the space of decomposition and past funerary practices.
... Some authors observed that termites attack bone material, mainly during dry seasons (Thorne & Kimsey, 1983). In addition, the entomological literature highlights the fact that termites have much more intense feeding behaviours on wood during periods of drought (Ahmed et al., 2011;Wightman, 1989Wightman, , 1991. This behaviour is explained by their constant search for moisture. ...
... Our aforementioned observations of termite feeding behaviour and nutritional requirements lend further support to our hypothesis regarding the nature of OH1's burial. In 90% of cases, subterranean termites build their nests near tree stumps and/or piles of decaying wood (Ahmed et al., 2011;Su & Bardunias, 2005), in other words, close to their main food source. However, in the case of OH1, to prove the presence of a plant cover or to estimate the vegetal concentration in the vicinity of a burial based on termite activity, additional experimentation would be needed to determine the level of attraction of termites to plant resources in contrast to fresh bones. ...
... Finally, previous researchers have argued that osteophageous behaviour in termites may reflect seasonal and nutritional needs during dry periods (Ahmed et al., 2011;Prestes et al., 2014;Queiroz et al., 2016;Thorne & Kimsey, 1983;Wightman, 1989Wightman, , 1991Wood & Johnson, 1978). Therefore, the extensive destruction of the OH1 skeleton also could be due to an extreme aridity period that would have intensified termites' osteophagic activities. ...
Article
Full-text available
This paper presents a case study of the Late Pleistocene skeletal remains of Olduvai Hominid 1 (OH1), which were unearthed in Tanzania. Excavated in 1913, this fossil shows severe damage due to subterranean termites (Insecta: Isoptera). By combining methods to quantify and locate traces on the skeleton with the study of the different taphonomic processes that altered the deposit, we demonstrate a non-arbitrary pattern of termite alteration of the skeletal remains. These results shed new light on the possibility to reconstruct the original position of a skeleton in a deposit and the potential to infer the space of decomposition and past funerary practices.
... The current issue and full text archive of this journal is available on Emerald Insight at: www.emeraldinsight.com/1756-8692.htm Climate change in Malaysian real estate 87 infrastructure and many other sectors of Malaysia in number of ways (Yusuf and Francisco, 2009;Shaffril et al., 2011;Begum et al., 2011;Vaghefi et al., 2011;Ahmed et al., 2011;Shahid et al., 2015;Shahid and Minhans, 2016). There is a growing concern in the recent years about climate change risks to real estate in the developed and developing countries (Parkinson, 2009;WRI, 2010;Toller et al., 2011;Butsic et al., 2011). ...
... Rouault et al. (2006) investigated the impacts of high temperatures on forest insects and noted that wood-borers were positively influenced by the high temperatures. Populations of many types of mites and insects responsible for destroying timber and wood products would benefit from climatic warming (Peterson, 2010;Ahmed et al., 2011). Ahmed et al. (2011) reported that the potential for increases in economically devastating termite outbreaks in response to climate change is high. ...
... Populations of many types of mites and insects responsible for destroying timber and wood products would benefit from climatic warming (Peterson, 2010;Ahmed et al., 2011). Ahmed et al. (2011) reported that the potential for increases in economically devastating termite outbreaks in response to climate change is high. It is likely 93 Climate change in Malaysian real estate that changes in termite populations will keep pace with gradual warming (Peterson, 2010). ...
Article
Full-text available
Purpose There is a growing concern in recent years regarding climate change risks to real estate in the developed and developing countries. It is anticipated that the property sector could be affected by variable climate and related extremes as well as by the strategies adopted to combat greenhouse gas (GHG) emissions. This paper aims to analyse the current knowledge regarding future climate changes to understand their possible impacts on the real estate sector of Malaysia with an aim to help stakeholders to adopt necessary responses to reduce negative impacts. Design/methodology/approach Available literature is reviewed and data related to climatic influences on buildings and structures are analysed to understand the climate change impacts on real estate in Malaysia. Findings The study reveals that temperature in the Peninsular Malaysia will increase by 1.1 to 3.6°C, rainfall will be more variable and river discharge in some river basins will increase up to 43 per cent during the northeast monsoon season by the end of this century. These changes in turn will pose risks of property damage and increase property lifecycle costs. Furthermore, property prices and the overall growth of the property sector may be affected by the government policy of GHG emission reduction by up to 45 per cent by the year 2030. This study concludes that the property sector of Malaysia will be most affected by the implementation of GHG emission reduction policy in the short term and due to the physical risk posed by variable climate and related extremes in the long term. Originality/value The study in general will assist in guiding the operational responses of various authorities, especially in terms of those interventions aimed at climate change risk reduction in the property sector of Malaysia.
... However, depending on the termite species (Ahmed et al., 2011) many other environmental and biological factors can influence termite mounds distribution, such as soil composition, inter and intra-species competition, and most importantly proximity to old termite mounds (Dangerfield, 1990). ...
... Finally, soil-feeding termites like most insects, are sensitive to habitat disturbance which can reduce vegetation biodiversity (Ahmed et al., 2011;Gillison et al., 2003). Since insects are nutritionally important for endangered great apes (IUCN, 2016) and the tropical forest ecosystem, it is of crucial importance to preserve high insect biodiversity. ...
Article
Abstract Objectives Insectivory likely contributed to survival of early humans in diverse conditions and influenced human cognitive evolution through the need to develop harvesting tools. In living primates, insectivory is a widespread behavior and frequently seasonal, although previous studies do not always agree on reasons behind this. Since western gorillas (Gorilla gorilla) diet is largely affected by seasonal variation in fruit availability, we aimed to test three non-mutually exclusive hypotheses (habitat use, frugivory and rainfall) to explain seasonality in termite feeding across age/sex classes in three habituated groups (Nindividuals = 27) in Central Africa. Materials and Methods We used 4 years of ranging, scan and continuous focal sampling records of gorillas (Nranging days = 883, Nscans = 12,384; Nhours = 891) in addition to 116 transects recording vegetation and termite mound distribution. Results Depending on the age/sex classes, we found support for all three hypotheses. Time spent in termite-rich vegetation positively impacted termite consumption in all age/sex classes, but subadults. Lengthier travels increased termite feeding in females but decreased it in subadults. Frugivory decreased termite consumption in adults. Daily rainfall had a positive effect on termite feeding and foraging in silverbacks and juveniles, but a negative effect in subadults. For females, rainfall had a positive effect on termite feeding, but a negative effect for termite foraging. Discussion In great apes, seasonal insectivory seems to be multifactorial and primarily opportunistic with important differences among age/sex classes. While insectivory has potentials to be traditional, it likely played a crucial role during primate evolution (including ours), allowing diet flexibility in changing environments.
... Although termites are abundant worldwide, Africa seems to be the richest in the number of termite species both known and identified with about 38% of recognized termites (United Nations Environment Programme [UNEP], 2000). The species richness is as a result of the friendly climatic conditions in Africa such that the family Termitidae has 664 African species (Ahmed et al., 2011). There are four known subfamilies under this family listed as follows: Apicotermitinae (70 species) (Kanwal, Acharya, Ramesh, & Reddy, 2011), Termitinae (272) African species (Eggleton, 2000), Macrotermitinae (165 species) (Eggleton, 1999), and Nasutitermitinae (56 species) (Mahaney et al., 1999). ...
... There are four known subfamilies under this family listed as follows: Apicotermitinae (70 species) (Kanwal, Acharya, Ramesh, & Reddy, 2011), Termitinae (272) African species (Eggleton, 2000), Macrotermitinae (165 species) (Eggleton, 1999), and Nasutitermitinae (56 species) (Mahaney et al., 1999). The total number of species in the above subfamilies may surpass 90% of the world's known termite species (Ahmed et al., 2011). ...
Article
Full-text available
Abstract Background Termites (Order Isoptera) are eusocial insects that are of great benefit and economic importance to humans. Despite its benefits and economic attributes to humans, it accounts for serious damage on buildings in Nigeria especially in the rural areas. The aim of this study was to collect preliminary data on termite infestation of the buildings in Ase, a local community in the Niger Delta region of Nigeria. Data was collected by direct observation of termites on the buildings, and a structured questionnaire was presented to respondents in houses with visual signs of infestation. Samples of termites were collected from parts of the houses with mud tubes or nests. Results A total of 106 houses were inspected with 35.85% infested with termites. The termites found were two species of Amitermes, one of Microcerotermes, three of Nasutitermes, two of Neotermes, and one of Odontotermes. Most infested homes (71%) were graded as moderate, severely damaged, and collapsed revealing a major problem. Percentage infestation of wood services revealed door frames 62.5% and wall (mud tubes) 87.75%, floor 18.85%, logs outside the house 56.25%, windows and roof 43.75%, ceiling 18.75%, and bathroom, furniture, and kitchen 6.25%. Respondents were 30–90 years old and did not attribute mud tubes to termite infestation. Seventy-two percent of the buildings were less than 60 years, and preventive measures used by respondents were Solignum and used engine oil. Most of the buildings were severely infested, and a
... The diverse and numerous microorganisms in the soil perform key functions within the environment by participating in the cycling and flux of various nutrients, thereby influencing structure formation and sustenance of soil properties (Holt and Lepage, 2000;Harry et al., 2001). Termites, a group of social insects consisting of over 2 600 species worldwide (Ahmed et al., 2011), are part of soil organisms that influence soil properties (Holt and Lepage, 2000;Harry et al., 2001;Manuwa, 2009;Muwawa et al., 2014). They are known as "soil engineers" as they have a great influence on the soil characteristics (Holt and Lepage, 2000), hence controlling diversity and activity of other soil organisms (Jones et al., 1997;Lavelle et al., 1997). ...
... The Macrotermitinae comprises of the economically important termite species (Ahmed et al., 2011) that have been comprehensively studied (Mathew et al., 2012;Makonde et al., 2013;Otani et al., 2014Otani et al., , 2015Muwawa et al., 2016). Previous studies have focused on the mutualistic symbiosis between Termitomyces sp. ...
Article
The fungus-cultivating termites (Macrotermitinae) form part of diverse termite fauna in Africa, but information on their fungal symbionts is inadequate and poorly understood. In this study, the fungal communities and structure between termite gut, mound and surrounding soil were determined using the 454 pyrosequencing-based analysis of the internal transcribed spacer (ITS) gene sequences. Genomic DNA was extracted and purified from the guts of three termites (Odontotermes sp., Macrotermes michaelseni and Microtermes sp.), mound and surrounding soil samples for high-throughput sequencing. A total of 15,256 sequences were obtained and individual samples contained between 4 and 133 operational taxonomic units (OTUs). Termite gut had the least fungal diversity, dominated by members of the Basidiomycota (> 98%). More than 98% of the gut sequences were of the genus Termitomyces, while < 2% were related to the genera Chaetomium, Fusarium, Eupenicillium, Cladosporium, Curreya and Phaeosphaeria with between 95 and 98% pair-wise sequence identities. Members of Ascomycota (> 94%) were the most abundant in the mound and soil, but significantly differed (P value of 0.04; R value = 0.909) between the mound and soil environments. The results confirm that the genus Termitomyces exist in a tight association with their hosts and that Termitomyces species are scarcely present in the mound and soil. In addition, by altering soil properties; the fungus-cultivating termites modify the fungal community composition and structure in the mound and surrounding soil environments.
... The role of termites as eco engineers is well documented in literature [33] but in SWRA increased termite attack is a phenomenon recently observed but not understood. Ahmed et al. [34] cite farmers in Uganda and Zambia as having more termite problems now than in the past. Damage by termites is greater during dry periods or droughts than periods of regular rainfall. ...
... The increases in termite damage could also be associated with climate change induced drought. In recent decades, drought linked to El Niño episodes has become more intense and widespread in southern Africa [34]. Environmental stresses such as extremes in temperature or moisture, site problems such as soil compaction, extremes in soil pH, poor soil texture for plant requirements, mechanical injuries to trunk or roots, insect infestations and diseases such as defoliating leaf diseases, root rots and wilt diseases. ...
Article
Full-text available
An investigation of the status of woodlands at Sengwa Wildlife Research Area (SWRA) revealed factors influencing decline and die-back of woody plants at a time of low elephant densities. The vegetation condition of the study area in the elephant range area of the semi-arid area of northwest Zimbabwe was randomly assessed in 50 × 20 m permanently marked degraded and undegraded plots in a study area approximately 80 km2. Diversity of woody plants increased towards downstream. Percentage elephant damage was slight on undegraded plots and termite damage was three times greater on undegraded plots than degraded plots. Density of woody plants was high following a period of coppice regeneration. The results suggest regeneration of woody plants following a long period of elephant culls between 1960 and 1992 that altered forest structures. It is conceivable that other environmental agents may play the role of elephant damage in the presence of elephant densities < 1 individuals/ km2. Significant differences (p<0.05) in elephant densities (no/km2) were recorded in SWRA between 1958 and 1996, 1958 and 1993 suggesting that increasing elephant densities were negatively impacting on woody cover (%). Woody cover increased from 60% in 1993 to 70% in 1996 inside SWRA. SWRA vegetation may be on regeneration path if no adverse impacts are recorded from other environmental agents including termite activity, fungal attack (Fusarium oxysporum), Lantana camara L. invasions and drought. Epidemic die-back is not yet a common feature in the protected area. The results refute the postulation that elephant alone prevent woodland regeneration and recruitment into larger size classes by feeding on small trees. The findings suggest need to consider end to end cycle of each disturbance factor in order to accurately predict scale of vegetation change in savanna ecosystems.
... Most farmers responded that they are using indigenous knowledge, such as mound opening and smoking, to control the effects of termites in this study area. This result is consistent with the findings of Djirata [15,35] in western Ethiopia. According to Sileshi et al. [36], sustainable termite management that does not result in ecological damage or loss of ecosystem services ensures long-term risk management. ...
Article
Full-text available
This study aimed to assess mound abundance, the livelihood impacts of termites, and determinant factors in the Meta Robi District, Ethiopia. A descriptive research design was used for primary data collection from the three selected kebeles. Termite nests were counted from each Goxi (the sub-kebele and the smallest unit in Ethiopia) using a transect line. In addition, 190 household heads were selected randomly from each kebele, and a questionnaire survey was used to collect primary data from the respondents. Termite nests were abundant in Warabo (7.25.71 per 1000 m²), but scarce in Warke Walensu Kebele (2.25.50 per 1000 m²). Teff (49.5%) and wheat (32.6%) were the most severely affected crops by termites. The mean annual hectare of land and quintals of teff and wheat damaged per household was higher in Warabo Kebele (p < 0.05). The annual economic loss from termites in crops was higher in Warabo (4722.23 ± 869.67 ETB and 4396.43 ± 852.65 ETB from teff and wheat per household, respectively). Agroecology, deforestation, overgrazing, and crop types were the factors that determined termite abundance and its impact on farmers' livelihoods. Mound opening and smoking are the management methods currently used, but no government support exists. Therefore, integrated and effective termite pest management is critical for long-term food security in the study area.
... The complexity and difficulty of understanding the relationship between termites and climate and land-cover changes are pronounced in the existing body of literature [48,81]. The recent literature on savanna ecosystems emphasized that if climate or landcover changes adversely affect termitaria, savanna ecosystems can become more homogeneous and vulnerable to ecosystem resilience of the ecosystem collapses with gradual effects on all ecosystem components [82,83]. ...
Article
Full-text available
Termites (Isoptera) are among the most globally dominant macroinvertebrates in terrestrial environments and are an ecologically important group of soil biota in tropical and subtropical ecosystems. These insects function as essential ecosystem engineers that facilitate nutrient cycling, especially in the regulation of the physical and chemical properties of soil and the decomposition of organic matter that maintains heterogeneity in tropical and subtropical ecosystems. Termites, like all living organisms, require certain environmental parameters to support the distribution, abundance , and activities of the species. South Africa's Kruger National Park (KNP)-one of the most important protected areas in the world and a popular safari tourist destination-is an extraordinary savanna ecosystem in which termite mounds, or termitaria, are widely distributed. A range of biotic and abiotic factors found in the natural environment of KNP provide highly suitable ecological conditions for termite habitat range, and thus the development of termitaria. Previous research has shown that the most important factors affecting habitat suitability for termites and the geographic distribution of termitaria include climate factors, land cover, and other environmental characteristics such as soil composition and plant-litter biomass. However, the specific environmental mechanisms that regulate termite occurrence and the spatial distribution of termitaria in KNP are not fully understood, especially in the context of climate and land-cover changes. The present study examines the relationship between the spatial distribution of termitaria and selected climate and environmental factors in the Kruger Lowveld region, which contains one of the largest numbers of ter-mitaria in KNP. Using high-resolution satellite imagery, 8200 training points of termitaria occurrence were collected throughout the study area to train classifiers and produce land-cover-classification maps for the Kruger Lowveld region of interest. We then applied a hybrid approach through the integration of remote sensing (RS) and a GIS-based analytical hierarchy process (AHP) and frequency ratio (FR) methods to model the relationship between the spatial distribution of termitaria and selected environmental variables and to produce suitability maps. To our knowledge, this study is the first of its kind to examine the influence of combined sets of environmental attributes on the spatial distribution of termitaria in the Lowveld region of KNP. The results indicate that moderately and highly suitable conditions for termite range tolerance and termitaria development are correlated with undulating plains with clay soils, greater distance to drainage streams, high solar radiation , and low depth of groundwater. The findings of this study shed light on the need for future research that investigates the impact of climate and land-cover changes on termite habitat range and spatial distribution and that can inform park managers and policymakers about Kruger National Park and other protected areas with similar environmental conditions. Citation: Ozsahin, E.; Ozdes, M.; Smith, A.C.; Yang, D. Remote Sensing and GIS-Based Suitability
... Cellulose is the most abundant biomaterial (Carbohydrate) on earth produced by plants. It is a linear polymer of glucose units, which are linked together by β-1,4 glycosidic bonds [1]. Cellulose is considered as the most important source of raw material for the enzymes that work synergistically to depolymerize the 1,4-glycosidic bonds [3]. ...
Article
Full-text available
Cellulase is a class of hydrolase enzymes with commercial and industrial value, it is commonly produced by microorganisms such as fungi, protozoans, bacteria and even insect that survives on cellulose. In this study, we evaluated the effect of immobilization on the kinetic parameters of partially purified cellulase from Macrotermes bellicosus. The cellulase was extracted from matured M. bellicosus and subjected the supernatant of the crude extract that has cellulase activity to gel filtration and ion-exchange chromatography. The enzyme was partially purified 2.0 fold with an overall yield of 40.4% on DEAE-cellulose column and a final specific activity of 51.0U/mg. The partially purified cellulase was immobilized by entrapment on calcium alginate beads. The free and immobilized enzyme showed an optimum temperature of 50 o C and 60 o C and optimum pH of 6.0 and 8.0 respectively. Initial velocity studies for the determination of kinetic constants with cellulose as a substrate revealed a K m value of 7.9 mg/ml and 3.4mg/ml with a V max value of 1.59 unit/mg and 1.15 unit/mg for the free and immobilized enzyme respectively. Both the free and immobilized cellulase activity was enhanced by Ca 2+ , and Mn 2+ but slightly decreased by Na +. While Mg 2+ and Zn 2+ were found to be strong inhibitors of both the free and immobilized enzyme. This research shows that cellulase from M. bellicosus could be immobilized and utilized for degradation of cellulose-containing materials because of their high catalytic activity, thermostability and acid-base stability, which reflect the potential industrial significance of the enzyme.
... Cellulose is the most abundant biomaterial (Carbohydrate) on earth produced by plants. It is a linear polymer of glucose units, which are linked together by β-1,4 glycosidic bonds [1]. Cellulose is considered as the most important source of raw material for the enzymes that work synergistically to depolymerize the 1,4-glycosidic bonds [3]. ...
Article
Full-text available
Cellulase is a class of hydrolase enzymes with commercial and industrial value, it is commonly produced by the microorganism such as fungi, protozoans, bacteria and even insect that survives on cellulose. In this study, we evaluated the effect of immobilization on the kinetic parameters of partially purified cellulase from Macrotermes bellicosus. The cellulase was extracted from matured M. bellicosus and subjected the supernatant of the crude extract that has cellulase activity to gel filtration and ion-exchange chromatography. The enzyme was partially purified 2.0 fold with an overall yield of 40.4% on DEAE-cellulose column and a final specific activity of 51.0U/mg. The partially purified cellulase was immobilized by entrapment on calcium alginate beads. The free and immobilized enzyme showed an optimum temperature of 50 o C and 60 o C and optimum pH of 6.0 and 8.0 respectively. Initial velocity studies for the determination of kinetic constants with cellulose as a substrate revealed a K m value of 7.9 mg/ml and 3.4mg/ml with a V max value of 1.59 unit/mg and 1.15 unit/mg for the free and immobilized enzyme respectively. Both the free and immobilized cellulase activity was enhanced by Ca 2+ , and Mn 2+ but slightly decreased by Na +. While Mg 2+ and Zn 2+ were found to be strong inhibitors of both the free and immobilized enzyme. This research shows that cellulase from M. bellicosus could be immobilized and utilized for degradation of cellulose-containing materials because of their high catalytic activity, thermostability and acid-base stability, which reflect the potential industrial significance of the enzyme.
Article
Full-text available
As part of the REgional Carbon Cycle Assessment and Processes Phase 2 (RECCAP2) project, we developed a comprehensive African Greenhouse gases (GHG) budget covering 2000 to 2019 (RECCAP1 and RECCAP2 time periods), and assessed uncertainties and trends over time. We compared bottom‐up process‐based models, data‐driven remotely sensed products, and national GHG inventories with top‐down atmospheric inversions, accounting also for lateral fluxes. We incorporated emission estimates derived from novel methodologies for termites, herbivores, and fire, which are particularly important in Africa. We further constrained global woody biomass change products with high‐quality regional observations. During the RECCAP2 period, Africa's carbon sink capacity is decreasing, with net ecosystem exchange switching from a small sink of −0.61 ± 0.58 PgC yr⁻¹ in RECCAP1 to a small source in RECCAP2 at 0.16 (−0.52/1.36) PgC yr⁻¹. Net CO2 emissions estimated from bottom‐up approaches were 1.6 (−0.9/5.8) PgCO2 yr⁻¹, net CH4 were 77 (56.4/93.9) TgCH4 yr⁻¹ and net N2O were 2.9 (1.4/4.9) TgN2O yr⁻¹. Top‐down atmospheric inversions showed similar trends. Land Use Change emissions increased, representing one of the largest contributions at 1.7 (0.8/2.7) PgCO2eq yr⁻¹ to the African GHG budget and almost similar to emissions from fossil fuels at 1.74 (1.53/1.96) PgCO2eq yr⁻¹, which also increased from RECCAP1. Additionally, wildfire emissions decreased, while fuelwood burning increased. For most component fluxes, uncertainty is large, highlighting the need for increased efforts to address Africa‐specific data gaps. However, for RECCAP2, we improved our overall understanding of many of the important components of the African GHG budget that will assist to inform climate policy and action.
Article
Full-text available
Termites are highly abundant and vital insects that directly and indirectly influence local soils. The present study investigated the morphological and molecular phylogenetics of termite species collected from study fields in southern Haryana, India, from 2020 to 2021. Samples were subjected to integrated systematic analyses, taking into account the mandible features of soldiers for morphological systematics and 16S rRNA gene-based phylogeny for molecular systematics. Based on the external phenotype and relations to reference sequences in NCBI GenBank, 21 species were identified; these included five species each from Odontotermes and Microcerotermes, four species from Coptotermes, two species each from Microtermes and Eremotermes, and one species each from Amitermes, Angulitermes, and Neotermes. 16S rRNA gene sequences were utilized to construct phylogenetic trees to explore the relatedness among identified species. The results of the different molecular phylogenetic approaches including maximum parsimony, maximum likelihood, and neighbor-joining revealed nearly identical topological relations between the species and grouping of individuals in relation to their genera. The maximum parsimony tree based on mandible features has been found to be effective in clustering multiple species of a given genus in a clade in at least three termite genera.
Article
African termites are classified into five distinct families, Termitidae, Rhinotermitidae, Hodotermitidae, Termopsidae and Kalotermitidae. Termites are undoubtedly one of the key ecosystem engineers. Because they harbour more nutritive plants, herbivory by large herbivores is biased towards mounds. Their engineering role is visible through construction of conspicuous termite mounds, which often harbour some unique species compared with the expansive ecosystem in which they occur. To understand the cascading effects of termite mounds on ecosystem functioning, we present a review on how termites create ecosystem heterogeneity, and how this heterogeneity in terms of soil physical and chemical characteristics, particularly nutrients, further influences vegetation production, diversity and palatability to large herbivores. Here we review literature mainly focusing on: (i) Phylogeny (evolutionary history) of African termites, (ii) mound construction, (iii) mound spatial distribution, (iv) termite foraging (v) termite nutrient cycling, (vi) termite influence on hydrology, (vii) termite mound influence on plant species diversity and (viii) termite mound influence on large herbivores. Our review showed that African termites are diverse, with the potential to influence ecosystems heterogeneity through soil nutrients enrichment, which in turn influences forage abundance (thicket clumps), diversity and quality. High forage quality occurring on termite mounds influences herbivory patterns in the savanna ecosystem. Herbivory is reported to be higher on termite mounds compared to the expansive savanna landscape. The most common plant family occurring on termite mounds is Capparaceae. We suggest that future studies focus more on: (1) the influence of termite mounds on plant functional traits, (2) the importance of termite mounds in dryland savanna cropping/rangeland systems, and (3) on ways to support establishment of mound building termite species.
Book
Full-text available
Nematology being an established discipline covers a wide range of area ranging from basic aspect to the advanced and applied aspects involving recent advances in molecular techniques. This book discusses the following topics: the role of nematodes in our life (in agriculture, ecosystem functioning, experimental biology, ecological studies, pest management programs, or biocontrol), identification of GRSPs in nematode genomes, novel way for the diagnosis of pathogenic nematodes involving various recent molecular techniques, other methodologies for successful control of termites, evolution of plant-parasitic nematodes, viability of adult filarial nematode parasites, the impact of plant-parasitic nematodes on crops, and harnessing useful rhizosphere microorganisms for nematode control. The book also encompasses on classical study, molecular study, bioinformatics in nematology, biodiversity analysis, and culturing of nematodes in laboratory condition.
Article
Full-text available
Termites constitute part of diverse and economically important termite fauna in Africa, but information on gut microbiota and their associated soil microbiome is still inadequate. In this study, we assessed and compared the bacterial diversity and community structure between termites’ gut, their mounds and surrounding soil using the 454 pyrosequencing-based analysis of 16S rRNA gene sequences. A wood-feeder termite (Microcerotermes sp.), three fungus-cultivating termites (Macrotermes michaelseni, Odontotermes sp. and Microtermes sp.), their associated mounds and corresponding savannah soil samples were analyzed. The pH of the gut homogenates and soil physico-chemical properties were determined. The results indicated significant difference in bacterial community composition and structure between the gut and corresponding soil samples. Soil samples (Chao1 index ranged from 1359 to 2619) had higher species richness than gut samples (Chao1 index ranged from 461 to 1527). The bacterial composition and community structure in the gut of Macrotermes michaelseni and Odontotermes sp. were almost identical but different from that of Microtermes and Microcerotermes species, which had unique community structures. The most predominant bacterial phyla in the gut were Bacteroidetes (40–58 %), Spirochaetes (10–70 %), Firmicutes (17–27 %) and Fibrobacteres (13 %) while in the soil samples were Acidobacteria (28–45 %), Actinobacteria (20–40 %) and Proteobacteria (18–24 %). Some termite gut-specific bacterial lineages belonging to the genera Dysgonomonas, Parabacteroides, Paludibacter, Tannerella, Alistipes, BCf9-17 termite group and Termite Treponema cluster were observed. The results not only demonstrated a high level of bacterial diversity in the gut and surrounding soil environments, but also presence of distinct bacterial communities that are yet to be cultivated. Therefore, combined efforts using both culture and culture-independent methods are suggested to comprehensively characterize the bacterial species and their specific roles in these environments. Electronic supplementary material The online version of this article (doi:10.1186/s40064-015-1262-6) contains supplementary material, which is available to authorized users.
Article
Full-text available
The interaction between termites and their gut symbionts has continued to attract the curiosity of researchers over time. The aim of this study was to characterize and compare the bacterial diversity and community structure in the guts of three termites (Odontotermes somaliensis, Odontotermes sp. and Microtermes sp.) using 16S rRNA gene sequencing of clone libraries. Clone libraries were screened by restriction fragment length polymorphism and representative clones from O. somaliensis (100 out of 330 clones), Odontotermes sp. (100 out of 359 clones) and Microtermes sp. (96 out 336 clones) were sequenced. Phylogenetic analysis indicated seven bacterial phyla were represented: Bacteroidetes, Spirochaetes, Firmicutes, Proteobacteria, Synergistetes, Planctomycetes and Actinobacteria. Sequences representing the phylum Bacteroidetes (>60 %) were the most abundant group in Odontotermes while those of Spirochaetes (29 %) and Firmicutes (23 %) were the abundant groups in Microtermes. The gut bacterial community structure within the two Odontotermes species investigated here was almost identical at the phylum level, but the Microtermes sp. had a unique bacterial community structure. Bacterial diversity was higher in Odontotermes than in Microtermes. The affiliation and clustering of the sequences, often with those from other termites' guts, indicate a majority of the gut bacteria are autochthonous having mutualistic relationships with their hosts. The findings underscore the presence of termite-specific bacterial lineages, the majority of which are still uncultured.
Chapter
Full-text available
Of the more than 2,300 termite species in the world, 183 species are known to damage buildings and 83 species cause significant damage. Subterranean termites, including mound building and arboreal species, account for 147 (80%) of the economically important species. The genus Coptotermes contains the largest number of pest species (28), whereas the genus Cryptotermes, especially Cr. brevis, is the most widely introduced. The world-wide economic impact figure of termites is uncertain, but the control cost for termite pests in the United States was estimated at $1.5 billion annually in 1994. Because of differences in their life histories, control measures differ between subterranean and drywood species. Insecticide barriers are used for exclusion of soil-borne subterranean termites, whereas slow-acting baits are used for population control of subterranean termite colonies in and near structures. Whole-structure treatments (fumigation and heat), compartmental treatments (heat or cold), and local treatments (wood surface treatments or insecticide injection) are the primary tools for drywood termite control.
Article
Full-text available
Despite their well-known role as pests, termites also provide essential ecosystem services. In this paper, we undertook a comprehensive review of studies on human-termite interactions and farmers' indigenous knowledge across Sub-Saharan Africa in an effort to build coherent principles for termite management. The review revealed that local communities have comprehensive indigenous knowledge of termite ecology and taxonomy, and apply various indigenous control practices. Many communities also have elaborate knowledge of the nutritional and medicinal value of termites and mushrooms associated with termite nests. Children and women also widely consume termite mound soil for nutritional or other benefits encouraged by indigenous belief systems. In addition, subsistence farmers use termites as indicators of soil fertility, and use termite mound soil in low-risk farming strategies for crop production. In the past, chemical control of termites has been initiated without empirical data on the termite species, their damage threshold, and the social, ecological, or economic risks and trade-offs of the control. This review has provided new insights into the intimate nature of human-termite interactions in Africa and the risks of chemical control of termites to human welfare and the environment. We recommend that management of termites in future should be built on farmers' indigenous knowledge and adequate understanding of the ecology of the local termite species.
Article
Full-text available
Article
Full-text available
Subterranean termites ('termites') are a major pest of human structures throughout tropical and sub-tropical regions, causing billions of dollars in damage to timber-in-service worldwide. Most control systems, in the past, relied almost solely on the use of extensively applied organochlorines as the major termiticides. These chemicals were banned for use as termiticides through out most of Australia in 1995. The banning of organochlorin es stimulated a fresh look and wholly biorational approach to termite control. The focus of research is now directed to finding more "environmentally friendly" termite control methods. In order to develop new possibilities for more acceptable termite control, it is necessary to have a clear understanding of their biology, including reproduction, division of labour, foraging, intra-specific and inter-specific interactions, hindgut microbial community and environmental influences. Improved understanding may lead to more efficient and more effective control strategies. The purpose of this review is to review the current research on Australian termites highlighting ongoing research related to development of alternative control methods and to identify areas in need of further study and funding
Article
Full-text available
In Zambia, termites have been recognized as pests of agricultural crops, plantation trees, structural timber, manufactured wooden goods as well as paper. This makes their control imperative. In line with the concept of pest management, appropriate control measures of termites must take into account their taxonomy, biology and ecology, as well the assessment of crop damage and yield losses. This paper discusses some of the problems inherent in developing such a scheme in Zambia and provides alternative solutions.RésuméEn Zambie les termites sont reconnus pour leur effet sur les récoltes. Les arbres, le bois de construction, des produits en bois ainsi que le papeir. Ceci rend la tâche de les contrôler impérative. Dans l'optique du concept du contrôle des termites devraient tenir compte de leurs taxonomie, biologie et ecologie, et déterminer aussi l'emplur de la destruction en perte de récolte. Ce compte rendu met en cause quelques uns des problémes inhérents en développement d'une tel programme en Zambie et propose d'autres solutions.
Article
Full-text available
Non-chemical control of termites in agriculture and forestry is attracting renewed interest following increasing restrictions on the use of persistent organochlorine (cyclodiene) insecticides. Non-chemical control involves methods which attempt, without using commercial pesticides, to (i) prevent termite access to the plants, (ii) reduce termite numbers in the vicinity of the plants or (iii) reduce susceptibility/increase resistance of the plants themselves. There have been few adequate trials of any of these methods. Numerous cultural procedures have been suggested, including measures to enhance plant vigour, to manipulate termite numbers and behaviour, and others whose mode of action is unclear. Many are simply part of good agricultural/silvicultural practice and to be recommended. Biological control by predators or pathogens is unlikely to be successful due to the termites' social structure and behavioural responses to infected individuals and to loss of individuals to predators. The use of ‘natural’ insecticides from locally available plant products may be effective in some cases but, as they are not subject to the same rigorous safety and environmental evaluation as commercial pesticides, their use cannot be sanctioned unconditionally. Other locally available products, e.g. wood ash, have not been adequately evaluated. Removal of reproductives from the nest and construction of physical barriers may have limited applications, but resistant species and varieties, combined with appropriate cultural methods and, perhaps, minimal use of modern pesticides in an integrated approach, offer the greatest potential for a long term solution. The lack of critical scientific evaluation of non-chemical control makes it a field wide open for research.
Article
Full-text available
Termites, particularly the mound building, fungus growing Macrotermitinae, reach densities of up to 400 termites m−2 in soils of dry tropical Africa. The influence of Macrotermi tinae in increasing certain soil nutrients in mounds compared to adjacent soils has been documented, but the links between litter harvesting by termites, soil fertility, and global C cycling have not been explored. This study reviews the evidence from soil science, ecology and atmos pheric chemistry and generates hypotheses to explain the role of termites in dry tropical eco systems. It is suggested that termite activity exhaustively partitions litterfall among adjacent com peting colonies, where it is so thoroughly decomposed that little or no organic C is incorporated into the soils. Associated N, P, and cations build up in the mounds, but C apparently is emitted as CO2 and CH4 from the mounds. While not adequate to calculate nutrient fluxes through termites, the data available support the argument that termites contribute significantly to atmospheric fluxes of CO2 and CH4. Moreover, they suggest a coupling of regional soil forming processes and the global C budget.
Article
Full-text available
The extent to which environmental heterogeneity can account for tree species coexistence in diverse ecosystems, such as tropical rainforests, is hotly debated, although the importance of spatial variability in contributing to species co-existence is well recognized. Termites contribute to the micro-topographical and nutrient spatial heterogeneity of tropical forests. We therefore investigated whether epigeal termite mounds could contribute to the coexistence of plant species within a 50 ha plot at Pasoh Forest Reserve, Malaysia. Overall, stem density was significantly higher on mounds than in their immediate surroundings, but tree species diversity was significantly lower. Canonical correspondence analysis showed that location on or off mounds significantly influenced species distribution when stems were characterized by basal area. Like studies of termite mounds in other ecosystems, our results suggest that epigeal termite mounds provide a specific microhabitat for the enhanced growth and survival of certain species in these species-rich tropical forests. However, the extent to which epigeal termite mounds facilitate species coexistence warrants further investigation.
Article
Full-text available
New approaches are needed to accelerate understanding of climate impacts on crop yields, particularly in tropical regions. Past studies have relied mainly on crop-simulation models or statistical analyses based on reported harvest data, each with considerable uncertainties and limited applicability to tropical systems. However, a wealth of historical crop-trial data exists in the tropics that has been previously untapped for climate research. Using a data set of more than 20,000 historical maize trials in Africa, combined with daily weather data, we show a nonlinear relationship between warming and yields. Each degree day spent above 30°C reduced the final yield by 1% under optimal rain-fed conditions, and by 1.7% under drought conditions. These results are consistent with studies of temperate maize germplasm in other regions, and indicate the key role of moisture in maize's ability to cope with heat. Roughly 65% of present maize-growing areas in Africa would experience yield losses for 1°C of warming under optimal rain-fed management, with 100% of areas harmed by warming under drought conditions. The results indicate that data generated by international networks of crop experimenters represent a potential boon to research aimed at quantifying climate impacts and prioritizing adaptation responses, especially in regions such as Africa that are typically thought to be data-poor.
Article
Full-text available
Dampwood termites of the genus Zootermopsis (Isoptera: Termopsidae) are an abundant group of basal termites found in temperate forests of western North America. Three species are currently recognized in the genus and one of these species is subdivided into two subspecies. Although morphological and genetic characters are useful in differentiating among the three species and the two subspecies, respectively, only hydrocarbon analysis can enable differentiation both among the three species and the two subspecies. Due to the limitations of hydrocarbon analysis, such as the need for fresh specimens, alternative methods that could rapidly and accurately identify Zootermopsis would be useful. Using a partial least squares analysis of near-infrared spectra, each of the Zootermopsis species and subspecies were identified with greater than 95% and 80% accuracy, respectively. Neural network analysis of the near-infrared spectra successfully enabled the identification of the species and subspecies with greater than 99% accuracy. The inexpensive, reproducible, and rapid nature of near-infrared spectroscopy makes it a viable alternative to morphological, hydrocarbon, or genetic analysis for identifying Zootermopsis.
Article
Full-text available
This study investigates likely changes in mean and extreme precipitation over southern Africa in response to changes in radiative forcing using an ensemble of global climate models prepared for the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4). Extreme seasonal precipitation is defined in terms of 10-yr return levels obtained by inverting a generalized Pareto distribution fitted to excesses above a predefined high threshold. Both present (control) and future climate precipitation extremes are estimated. The future-to-control climate ratio of 10-yr return levels is then used as an indicator for the likely changes in extreme seasonal precipitation. A Bayesian approach to multimodel ensembling is adopted. The relative weights assigned to each of the model simulations is determined from bias, convergence, and correlation. Using this method, the probable limits of the changes in mean and extreme precipitation are estimated from their posterior distribution. Over the western parts of southern Africa, an increase in the severity of dry extremes parallels a statistically significant decrease in mean precipitation during austral summer months. A notable delay in the onset of the rainy season is found in almost the entire region. An early cessation is found in many parts. This implies a statistically significant shortening of the rainy season. A substantial reduction in moisture influx from the southwestern Indian Ocean during austral spring is projected. This and the preaustral spring moisture deficits are possible mechanisms delaying the rainfall onset in southern Africa. A possible offshore (northeasterly) shift of the tropical–temperate cloud band is consistent with more severe droughts in the southwest of southern Africa and enhanced precipitation farther north in Zambia, Malawi, and northern Mozambique. This study shows that changes in the mean vary on relatively small spatial scales in southern Africa and differ between seasons. Changes in extremes often, but not always, parallel changes in the mean precipitation.
Article
Full-text available
Data are presented for termite assemblages across an anthropogenic disturbance gradient in the humid forest zone of West and Central Africa. Sampling was by standardised 100 mx2 m transects in: primary forest, several ages of regenerating forest, agroforestry plots, short fallows, mixed food crop fields, and mechanically cleared plots. Most sites were in southern Cameroon––two additional transects were conducted in primary forest in Congo (Brazzaville). Species richness was negatively correlated with the disturbance gradient, although transects in areas with a complete or near-complete canopy were broadly similar in species richness. The strongest negative correlation was found for termite species feeding furthest down the humification gradient (group IV soil feeders) probably because these species are energetically constrained from living in non-forest habitats. In contrast species feeding and nesting in dead wood (group I wood feeders) termites, which live in the most protected micro-habitats, were significantly positively correlated with the disturbance gradient. Species composition was also strongly correlated with disturbance level in multivariate redundancy analyses. Pest species were an insignificant element of the assemblage, in part because of the distance of the sites from savanna source pools. Overall, it appears that termite-mediated wood and litter decomposition may be relatively unaffected by light to moderate disturbance intensity, but that soil-conditioning by termites might be greatly reduced in agricultural land cleared from tropical forest.
Article
Full-text available
A synthesis is presented of sampling work conducted under a UK government-funded Darwin Initiative grant undertaken predominantly within the Danum Valley Conservation Area (DVCA), Sabah, East Malaysia. The project concerned the assemblage structure, gas physiology and landscape gas fluxes of termites in pristine and two ages of secondary, dipterocarp forest. The DVCA termite fauna is typical of the Sunda region, dominated by Termes-group soil-feeders and Nasutitermitinae. Selective logging appears to have relatively little effect on termite assemblages, although soil-feeding termites may be moderately affected by this level of disturbance. Species composition changes, but to a small extent when considered against the background level of compositional differences within the Sunda region. Physiologically the assemblage is very like others that have been studied, although there are some species that do not fit on the expected body size-metabolic rate curve. As elsewhere, soil-feeders and soil-wood interface-feeders tend to produce more methane. As with the termite assemblage characteristics, gross gas and energy fluxes do not differ significantly between logged and unlogged sites. Although gross methane fluxes are high, all the soils at DVCA were methane sinks, suggesting that methane oxidation by methanotrophic bacteria was a more important process than methane production by gut archaea. This implies that methane production by termites in South-East Asia is not contributing significantly to the observed increase in levels of methane production worldwide. Biomass density, species richness, clade complement and energy flow were much lower at DVCA than at a directly comparable site in southern Cameroon. This is probably due to the different biogeographical histories of the areas.
Article
Full-text available
Fluorescence spectrophotometry can reliably detect levels of the pteridine 6-biopterin in the heads of individual Drosophila serrata Malloch 1927. Pteridine content in both laboratory and field captured flies is typically a level of magnitude higher than the minimally detectable level (mean(lab)=0.54 units, mean(field)=0.44 units, minimum detectable level=0.01 units) and can be used to predict individual age in laboratory populations with high certainty (r2=57%). Laboratory studies of individuals of known age (from 1 to 48 days old) indicate that while pteridine level increases linearly with age, they also increase in a linear manner with rearing temperature and ambient light levels, but are independent of sex. As expected, the longevity of laboratory-reared males (at least 48 days) is higher than the range of predicted ages of wild-caught males based on individual pteridine levels (40 days). However, the predictive equation based on pteridine level alone suggested that a number of wild-caught males were less than 0 days old, and the 95% confidence limits for these predictions based on the inverse regression are broad. The age of the oldest wild-caught male is predicted to fall within the range of 2 to 50 days. The significant effects of temperature and light intensity determined in the laboratory study (effect sizes omega2=14.3 and 20.4%, respectively) suggests that the calibration of the age prediction equation for field populations would be significantly improved when combined with fine-scaled studies of habitat temperature and light conditions. The ability to determine relative age in individual wild-caught D. serrata presents great opportunities for a variety of evolutionary studies on the dynamics of natural populations.
Article
The causes and impacts of famine and desertification in Umm Ruwaba district, Kordofan Region, Sudan, are examined. This eastern extension of the Sahel is a semi-arid area inhabited largely by sedentary cultivators. The drought of 1983-1984 led to severe famine in the district, largely because the local inhabitants had conformed to the government policy of commercializing a substantial fraction of their crop production (a component of which was to encourage regional specialization), that has led to a partial abandonment of their traditional land-use and food-storage practices. Desertification in the district has been attributed largely to a shortening of the soil-renewing fallow period, carried out in an attempt to make up for declining crop yields per unit area; and also to overexploitation of the protective tree cover, largely for the making of charcoal, as a source of needed cash income. -Author
Article
Rapid estimates of termite mounds exceeding 1 m in height were made by roadside counts covering most of Uganda. The error in the counts was estimated at about 3% and the counts reflected the abundance of mounds in the local areas. The density of mounds in most parts of Uganda is 1-4 ha1^{-1}, only a small proportion of the country having more. The total quantities of soil incorporated in the mounds were comparatively small, equivalent to a layer less than 1 mm thick over most of the country. Mounds were absent from higher ground, the upper limits corresponding to a mean minimum temperature of 9^\circ C for Macrotermes subhyalinus and 12^\circ C for M. bellicosus. There were several areas where M. subhyalinus occurred alone, but few were occupied exclusively by M. bellicosus. In most places both were present but it was usual for one to be dominant. The shape of mounds varies considerably, partly in response to climate. For example, `turrets' on M. bellicosus mounds are more common where the mean maximum temperature exceeds 28^\circ C and the ratio precipitation:evaporation is 0·6 or less. Mound shape in Uganda was not correlated with the sandiness of the soil.
Article
Recent estimates for global warming predict increases in global mean surface air temperatures (relative to 1990) of between 1 and 3.5 °C, by 2100. The impact of such changes on agricultural systems in mid- to high-latitude regions are predicted to be less severe than in low-latitude regions, and possibly even beneficial, although the influence of pests and diseases is rarely taken into account. Most studies have concluded that insect pests will generally become more abundant as temperatures increase, through a number of inter-related processes, including range extensions and phenological changes, as well as increased rates of population development, growth, migration and over-wintering. A gradual, continuing rise in atmospheric CO2 will affect pest species directly (i.e. the CO2 fertilization effect) and indirectly (via interactions with other environmental variables). However, individual species responses to elevated CO2 vary: consumption rates of insect herbivores generally increase, but this does not necessarily compensate fully for reduced leaf nitrogen. The consequent effects on performance are strongly mediated via the host species. Some recent experiments under elevated CO2 have suggested that aphids may become more serious pests, although other studies have discerned no significant effects on sap-feeding homopterans. However, few, if any of these experiments have fully considered the effects on pest population dynamics. Climate change is also considered from the perspective of changes in the distribution and abundance of species and communities. Marked changes in the distribution of well-documented species - including Odonata, Orthoptera and Lepidoptera - in north-western Europe, in response to unusually hot summers, provide useful indications of the potential effects of climate change. Migrant pests are expected to respond more quickly to climate change than plants, and may be able to colonize newly available crops/habitats. Range expansions, and the removal of edge effects, could result in the increased abundance of species presently near the northern limits of their ranges in the UK. However, barriers to range expansions, or shifts, may include biotic (competition, predation, parasitism and disease), as well as abiotic, factors. Climatic phenomena, ecosystem processes and human activities are interactive and interdependent, making long-term predictions extremely tenuous. Nevertheless, it appears prudent to prepare for the possibility of increases in the diversity and abundance of pest species in the UK, in the context of climate change.
Article
My aim in writing this book was to help reduce the huge gap between what is understood about global warming by the relevant scientific community and what is known by the public. The story describes my recent journey in trying to inform governments of the urgency of actions to stabilize climate, discovery of the universality of greenwash by governments that have no intention of bucking fossil fuel special interests, and realization of the implications for my children and grandchildren. In the year following the publication of this book the gap mentioned above has increased. Objective assessment of the science and lack of appropriate governmental response has clear implications for communication by the scientific community and actions by concerned public citizens, as will be discussed.
Article
Thirty-nine available family-group names are identified within the insect order Isoptera (termites). For all names the correct author, date, type genus, and combining stem are provided for the first time. This nomenclatural compilation is done to stabilize the usage of family- group names in the Isoptera in advance of a world catalog. Several problems of priority are identified and discussed. The little understood subfamily Foraminitermitinae is diagnosed; while generally believed by many authors to be a new, unnamed subfamily, it was in fact established by Holmgren nearly a century ago. The subfamilies Syntermitinae and Sphaerotermitinae are newly proposed for the mandibulate genera of nasute termites and for Sphaerotermes, respectively. The classification of Isoptera is briefly outlined.
Article
As agroforestry technologies are developed and promoted, there is a need to integrate indigenous knowledge about pest identification and management techniques into the scaling-up process in order to improve farmers' pest management practices. This paper documents farmers' knowledge, perceptions and management practices against termites in agroforestry in Tororo District, Uganda. The applicability and implications of such information in the development and promotion of sustainable termite management in agroforestry are discussed. Research findings • Farmers have a deep understanding of the diversity, abundance and distribution of termites in their villages. Simple features such as mound building character, mound morphology, timing of alate flights, and size, colour and/or odour of workers, soldiers and alates are effective indigenous termite identifying characteristics. • Termite damage is the most limiting constraint in tree cultivation in Tororo District, but some termite species are important food sources. Other highly rated problems in tree growing include lack of planting materials, drought and attacks by moles and defoliating caterpillars.  Macrotermes bellicosus and M. subhyalinus are considered the most abundant termite species in Tororo District, attacking the widest range of trees and crops, and causing the most damage. However, the farmers know some tree species and crops which are not attacked by any termite species.  Farmers have attempted several termite control methods, including application of plant extracts, cow and human urine, heat and/or smoke, dead animals, chemical pesticides and the physical removal of the queen or destruction of the mound. However most of them lack knowledge of these methods of control or the skills to apply them properly, and they consider this to be their most important constraint in managing the termite problem. Policy implications  Termite damage in agroforestry is an important issue demanding concerted efforts and resources to develop new management approaches that build on, rather than destroy or ignore, farmers' indigenous knowledge and practices.  Indigenous pest identification and control practices in agroforestry need to be documented, verified, standardised, adapted and promoted to farmers with other integrated pest management (IPM) measures with the aim of reducing the application of chemical pesticides.  Mechanisms are needed to train farmers and encourage farmer-to-farmer transfer of appropriate pest management information. The farmers' field school approach and community advisory concept could be excellent ways for agencies promoting agroforestry to generate and spread IPM information.
Article
Termites are a large and diverse group, comprising roughly 281 genera and over 2600 described species. At present, seven families and 14 subfamilies are recognized. A large majority (ca. 85%) of known genera are included in one family, Termitidae. The present classification, as used since 1972, has been moderately stable but suffers from a lack of good defining synapomorphies for several groups and a rearrangement of taxa is desirable. At the evolutionary level, phylogenetic hypotheses proposed for Isoptera have one or more of these failings: a lack of cladistic analysis, too few characters, or poor taxon sampling. Surprisingly, the first cladistic phylogenetic hypothesis was published only in 1996, but three further studies have been overtaken subsequently. Mastotermitidae are generally accepted as the basal family, but in contrast there is little consensus on relationships among the sub-basal families and among subfamilies within the Termitidae. Recent advances in molecular techniques, cladistic analyses and increased cooperation among scientists employing disparate character sets presage a resolution of these problems. Appendices list described genera and estimate species numbers. There is an annotated key to families and subfamilies.
Book
This book, from a 1993 symposium, focuses on current, anthropogenic changes in insect populations using five major sections: introduction; changes in climate; changes in gas/pollutant levels; changes in land use; and a section of shorter papers. The effects of climate change on insects are assessed using techniques ranging from fossil evidence to simulation models to remote sensing. The section on changes in gas levels addresses a series of individually studies of insect responses to atmospheric gases and other pollutants. The section focusing on the effects of environmental change on insects is well documented.
Article
The distribution of termites in north-eastern Tanganyika is discussed in relation to eight zones delimited by contours and vegetation types. Some termites show very definite limits to their distribution; Hodotermes mossambicus (Hagen) and Amitermes lonnbergianus (Sjöstedt) are examples. The significance of this is discussed. There is a greater variety of T ermitinae near the coast, while the subterranean termites are the more abundant in dry bushland. Some species are able to extend their distribution where gallery forest is found along the larger rivers. Two types of mountain forest are included in the region and extremely few termites are to be found within these. The distribution of termites observed on descending from the mountains to the plains is discussed and illustrated by a diagram. In addition, two methods of indicating the relative abundance of termites in the soil is described.
Article
The appearance of the digestive tube in situ is shown to be valuable in the identification of worker termites, particularly those of detritus and soil feeding species. Genera, and sometimes species, can be identified by this character. These preliminary findings will be of assistance to termite ecologists interested in population studies, where problems of the identification of mixed samples containing workers from cores or other soil samples are a serious problem.
Article
Recent estimates for global warming predict increases in global mean surface air temperatures (relative to 1990) of between 1 and 3.5 °C, by 2100. The impact of such changes on agricultural systems in mid- to high-latitude regions are predicted to be less severe than in low-latitude regions, and possibly even beneficial, although the influence of pests and diseases is rarely taken into account. Most studies have concluded that insect pests will generally become more abundant as temperatures increase, through a number of inter-related processes, including range extensions and phenological changes, as well as increased rates of population development, growth, migration and over-wintering. A gradual, continuing rise in atmospheric CO2 will affect pest species directly (i.e. the CO2 fertilization effect) and indirectly (via interactions with other environmental variables). However, individual species responses to elevated CO2 vary: consumption rates of insect herbivores generally increase, but this does not necessarily compensate fully for reduced leaf nitrogen. The consequent effects on performance are strongly mediated via the host species. Some recent experiments under elevated CO2 have suggested that aphids may become more serious pests, although other studies have discerned no significant effects on sap-feeding homopterans. However, few, if any of these experiments have fully considered the effects on pest population dynamics. Climate change is also considered from the perspective of changes in the distribution and abundance of species and communities. Marked changes in the distribution of well-documented species – including Odonata, Orthoptera and Lepidoptera – in north-western Europe, in response to unusually hot summers, provide useful indications of the potential effects of climate change. Migrant pests are expected to respond more quickly to climate change than plants, and may be able to colonize newly available crops/habitats. Range expansions, and the removal of edge effects, could result in the increased abundance of species presently near the northern limits of their ranges in the UK. However, barriers to range expansions, or shifts, may include biotic (competition, predation, parasitism and disease), as well as abiotic, factors. Climatic phenomena, ecosystem processes and human activities are interactive and interdependent, making long-term predictions extremely tenuous. Nevertheless, it appears prudent to prepare for the possibility of increases in the diversity and abundance of pest species in the UK, in the context of climate change.
Article
Objectives: To (1) assess the strength of evidence for the role of termites in vegetation heterogeneity in African savannas, and (2) identify the mechanisms by which termites induce such heterogeneity. Location: African savannas. Methods: We conducted a review of the literature, a meta-analysis and qualitative systems analysis to identify mechanisms to explain the observed patterns. Results: The review provided evidence for termite-induced heterogeneity in floristic composition and vegetation patterning in savannas across Africa. Termites induced vegetation heterogeneity directly or indirectly through their nest-building and foraging activities, associated nutrient cycling and their interaction with mammalian herbivores and fire. The literature reviewed indicated that termite mounds essentially act as islands of fertility, which are responsible for ecosystem-level spatial heterogeneity in savannas. This was supported by the meta-analysis, which demonstrated that mounds of Ancistrotermes, Macrotermes, Odontotermes (family Macrotermitinae), Cubitermes (family Termitinae) and Trinervitermes (Nasutitermitinae) are significantly enriched in clay (75%), carbon (16%), total nitrogen (42%), calcium (232%), potassium (306%) and magnesium (154%) compared to the surrounding savanna soil. Conclusions: Termite activity is one of the major factors that induce vegetation patterning in African savannas. The implications of this are discussed and research questions for future studies and modelling efforts are indicated.
Article
Two study‐sites near Kampala were mapped and all of the termite mounds within them were measured. Changes were recorded in the three succeeding years. A method was developed for estimating mound volumes from height and diameter. Macrotermes bellicosus mounds reached a volume of about 2.4 m ³ in 3 years after which they grew more slowly to a maximum from 4 to 6 m ³ . Growth in volume during the first 3 years was approximately linear and its rate did not vary seasonally, probably because growth is related to temperature which was nearly constant throughout the year. M.bellicosus mounds had an average length of life of about 10 years, although colonies survived on average only 4 years. The corresponding figures for Pseudacanthotermes spp. were 5 and 2 1/2 years. Some mounds were recolonized after the death of the original colony. Fresh earth was brought up at a minimum rate of about 10 m ³ ha ‐1 yr ‐1 but more was lost by erosion and destruction and the populations of mounds were decreasing. The number of ventilation shafts in M.bellicosus mounds increased with the volume of the mound. Many mounds, both dead and alive, supported vegetation. Local opinion is that Pseudacanthotermes are harmless but M.bellicosus is regarded as a pest and attempts are made to destroy its mounds.
Article
To develop an inventory of the present knowledge about soil-borne pests (insects, fungi, nematodes and bacteria) in Uganda, we review in this paper, aspects of their diversity, abundance, distribution in agro-ecosystems control approaches as well as their role in sustainable land management. Knowledge gaps about the soil pests and short falls in human resource capacity are identified as possible factors affecting the development of appropriate management packages for the soil pests. Priority research areas and capacity building needs are suggested.
Article
Abstract  The main aim of this paper is to present humanity and termites as design partners in the creation of a new dimension of ecosystem understanding. The paper by Turner and Soar, “Beyond biomimicry: What termites can tell us about realizing the living building” (2008) opens up a new era in how we think of human habitations, not only on earth, but perhaps on other planets, and using the termite model as the corner stone of innovative engineering. We know that termites are masters of constructing ‘buildings’ that meet all nutrition, energy, waste disposal needs, shelter, and food sources for many other animals and insects. We need to emulate the symbiotic abilities of termites to survive over time, for we all live on this symbiotic planet, and symbiosis is natural and common.
Article
The Macrotermitinae are a large and successful subfamily of fungus-growing termites, characterised by their symbiotic association with white-rot fungi of the genus Termitomyces. The taxonomy of the subfamily, and in particular of the largest genus Odontotermes, is problematic. We used sequences of the mitochondrial 16S gene from termites occurring in East Africa and Malawi to explore the phyletic relationships within the genus Odontotermes and to place the genus in the broader context of other fungus-growing termites. We also interpret this phylogeny in relation to classical morphological taxonomy in the form of absolute and relative dry weights of the sterile castes, and in relation to innate behaviour as shown by nest architecture and fungus comb structure. This work lays the foundations of a complete taxonomic revision of the Macrotermitinae. The phylogeny supports one clear subdivision, here called the “tanganicus” group, within the genus Odontotermes. It also supports the significance of field observations on the structure of fungus combs, as the whole “tanganicus” group builds fungus combs of the sponge type (or modified forms thereof) which are hardly known elsewhere. Other phyletic relationships are less clear, the residual sequences being referred to as the “latericius” group. We recognise three probable miniature species within the “tanganicus” group and another possible one in the residual “latericius group”.
Article
Part One of the Report summarises the outcomes of an industry workshop organised to better scope the subterranean termite problem, identify knowledge gaps, including R&D gaps, and identify strategies, including cost-effective coordination mechanisms for addressing the issue. Part Two is a brief review of the current state of knowledge on subterranean termites of economic importance to the wood products industry in Australia.
Article
Determining malaria vector species and age is crucial to measure malaria risk. Although different in ecology and susceptibility to control, the African malaria vectors Anopheles gambiae sensu stricto and An. arabiensis are morphologically similar and can be differentiated only by molecular techniques. Furthermore, few reliable methods exist to estimate the age of these vectors, which is a key predictor of malaria transmission intensity. We evaluated the use of near-infrared spectroscopy (NIRS) to determine vector species and age. This non-destructive technique predicted the species of field-collected mosquitoes with approximately 80% accuracy and predicted the species of laboratory-reared insects with almost 100% accuracy. The relative age of young or old females was predicted with approximately 80% accuracy, and young and old insects were predicted with > or = 90% accuracy. For applications where rapid assessment of the age structure and species composition of wild vector populations is needed, NIRS offers a valuable alternative to traditional methods.
Article
With confirmation of anthropogenically induced climate change, the spotlight is on biologists to predict and detect effects on populations. The complexity of interactions within and between the biotic and abiotic components involved makes this a tough challenge, and most studies have consequently considered effects of only single climate variables on single species. However, some have gone further, and recently published long-term datasets now offer opportunities that complement new experimental approaches that span trophic levels. With these datasets, predicting relative shifts in temporal and spatial associations could be among the most tractable problems.
Article
The families Termitidae and Rhinotermitidae are the most evolved and diverse groups of the social insects, termites (Order Isoptera), showing elaborated morphology and complex behavior. Molecular phylogeny of termites with the emphasis on these families was examined by Bayesian and maximum-likelihood analyses based on DNA sequence of mitochondrial cytochrome oxidase II (COII) gene of 31 genera sampled in Asia (mainly Thailand and Japan) along with those reported previously. Termitidae was monophyletic and originated from within polyphyletic Rhinotermitidae. Among the four subfamilies of Termitidae, Macrotermitinae was monophyletic suggesting a single common origin of fungus-growing habit characteristic for this subfamily, and was placed in the basal position in the family. A group consisting of other subfamilies Termitinae and Nasutitermitinae, though some important groups were still untouched, was the most apical but neither Termitinae nor Nasutitermitinae formed a monophyletic lineage. It was implied that, as defense systems of the soldier castes, the appearance of snapping mandibles has occurred at a single event, but the development of nasus for chemical secretion has probably not. Our tree provides some evidence concerning contradictions in the previously proposed phylogeny of termites.
Article
Six Australian species of Coptotermes are traditionally recognized, but recent cuticular hydrocarbon studies suggest that some of these may represent more than one species. An understanding of the phylogenetic diversity of Australian Coptotermes, particularly the pest species, is likely to be important for the improvement of termite management strategies. A study of phylogenetic relationships among species of this genus was performed, based on the mitochondrial cytochrome oxidase (COII) gene, comparing the data with recent data from Asian species. Representatives of the species C. lacteus (Froggatt), C. frenchi Hill and C. michaelseni Silvestri were each found to form closely related monophyletic groups, however representatives of C. acinaciformis (Froggatt) were not. For C. acinaciformis, representatives from northern mound-building populations were found to form a distinct group to southern, tree-nesting forms. Among southern C. acinaciformis, two Western Australian representatives were found to be divergent from other populations. The results suggest that C. acinaciformis probably represents a complex of species rather than one, as has been suggested previously. One unidentified Coptotermes sp. taxon from Melbourne was found to be divergent from other taxa. Notably, some Australian species were more closely related to Asian species than other Australian species.
Biomimicry of termite engineering for water and soil conservation. SOCIAL SCIENCES CONFERENCE
  • B M Ahmed
  • A Elmahdi
  • J R J French
  • R Edis
Ahmed, B.M., Elmahdi, A., French, J.R.J., Edis, R. (2006). Biomimicry of termite engineering for water and soil conservation. SOCIAL SCIENCES CONFERENCE 2007. The International Conference on Interdisciplinary Social Sciences. University of Granada, Granada, Spain, 10-13 July, 2007.
Problems in identification and control of termites
  • R K Bagine
Bagine, R. K. (1992). Problems in identification and control of termites In: Proceedings of the 1st Regional Workshop on Termite Research and Control, Wetlands, Nairobi, Kenya.
On some particulars in the natural history and habits of termites
  • G Bates
Bates, G. (1854). On some particulars in the natural history and habits of termites. In. Proc. Linn. Soc. London., Vol. 2. Pp. 333.