Department of Botany

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Abundance and Diversity of Seagrass and Macrofauna in the Intertidal Areas with and Without Seaweed Farming Activities in the East Coast of Zanzibar
(Tanzania Journal of Science, 2009-07) Lyimo, Thomas J.; Mvungi, Esther F.; Mgaya, Yunus D.
The diversity and abundance of seagrass and associated macrofauna were studied in transects with and without seaweed farms at Chwaka Bay and Jambiani, in the East Coast of Zanzibar. Eight seagrass species, namely Cymodocea rotundata, Cymodocea serrulata, Thalassia hemprichii,Thalassodendron ciliatum, Syringodium isoetifolium, Halodule uninervis, Halophila ovalis and Enhalus acoroides were recorded in the transects. The mean total biomass of seagrass at Chwaka Bay ranged from 142.4 ± 70.71 to 1652 ± 772.7 g dw/m2 and 212.9 ± 146.2 to 1829 ± 1692 gdw/m2 in station with and without seaweed farms, respectively. At Jambiani, the mean total biomass ranged from 880.4 ± 336.8 to 3467 ± 549.9 and 203.4 ± 102.4 to 3810 ± 2770 g dw/m2 in station with and without seaweed farms, respectively. The overall total biomass of seagrasswas significantly lower (KW = 108.7, p < 0.0001) in station with seaweed farms than in stations without seaweed farms. A total of 93 macrofauna species representing 60 families were encountered and the mean density ranged from 910 to 6990 individuals/m2 at Chwaka Bay andJambiani in stations with and without seaweed farms respectively. The most common macrofauna species were Codakia punctata, Meropesta nicobarica, Echinometra mathaei, Pinna muricata and Clibanarius emystemus. It was shown that the macrofauna abundance and diversity was higher in stations without seaweed farms than in the stations with seaweed farms, which could be due to activities associated with seaweed farming which contributed to the loss of diversity and biomass of flora and macrofauna of the seagrass meadows.
Allanblackia, A New Tree Crop in Africa for The Global Food Industry: Market Development, Smallholder Cultivation And Biodiversity Management
(Taylor & Francis, 2009-12) Jamnadass, Ramni; Dawson, Ian K.; Anegbeh, Paul; Asaah, Ebenezar K.; Atangana, Alain; Cordeiro, Norbert J.; Hendrickx, Harrie; Henneh, Samuel; Kadu, Caroline A. C.; Kattah, Cyril; Misbah, Maha; Muchugi, Alice; Munjuga, Moses; Mwaura, Lucy; Ndangalasi, Henry J.; Njau, Chrispine S.; Nyame, Samuel K.; Ofori, Daniel A.; Peprah, Theresa; Joanne, Russel; Rutatina, Fidelis; Sawe, Corodius; Lars, Schmidt; Tchoundjeu, Zac; Simons, Tony
The seeds of Allanblackia trees produce edible oil with significant global market potential. Consequently, a private-public partnership involving Unilever and known as 'Novella Africa' is engaged in the development of Allanblackia as a new crop in a number of African countries. The purpose of this partnership is to build a profitable and sustainable initiative for harvest, marketing and cultivation. Rural communities are directly involved and a participatory approach to domestication is being followed to maximise fanners' livelihood benefits. This is the first time a multinational company has partnered in such an approach, and the initiative represents an example for the domestication of other new tree crops. Investing in good communication between partners is considered to be essential to success by ensuring trust and a common understanding of priorities. Progress to date has involved the establishment of market supply chains for oil, based firstly on wild harvest, and the initiation of cultivation by smallholders. Further work will involve the development of rural resource centres to deliver improved germplasm to growers. At the same time, these centres will provide other services such as market information, credit and access to buyers. Through this strategy it is foreseen that there will be progress towards the development of a market value chain which removes producers' constraints to profitable involvement. Furthermore, the diversification of farmers' cropping systems should have positive impacts for biodiversity and provide resilience in the face of climate change. Currently, the most important activity under the initiative is the promotion of Allanblackia planting, so that production constraints do not hamper market development.
Ancistrotanzanine A, the First 5,3‘-Coupled Naphthylisoquinoline Alkaloid, and Two Further, 5,8‘-Linked Related Compounds from the Newly Described Species Ancistrocladus tanzaniensis # ,1
(2003-09) Bringmann, Gerhard; Dreyer, Michael; Faber, Johan H.; Dalsgaard, Petur W.; Staerk, Dan; Jaroszewski, Jerzy W.; Ndangalasi, Henry J.; Mbago, Frank M.; Brun, Reto; Reichert, Matthias; Maksimenka, Katja; Christensen, Søren B.
The first phytochemical investigation of the recently discovered East African liana Ancistrocladus tanzaniensis is described, resulting in the isolation and structural elucidation of two new naphthylisoquinoline alkaloids, ancistrotanzanines A (5) and B (6), and the known compound ancistrotectoriline A (7). Ancistrotazanine A (5) represents a hitherto unprecedented 5,3'-coupling type between the naphthalene and isoquinoline portions, while 6 and 7 are 5,8'-coupled. The structures of the compounds were determined by spectroscopic, chemical, and chiroptical methods. Compounds 5 and 6 showed good activities against the pathogens of leishmaniasis and Chagas' disease, Leishmania donovani and Trypanosoma cruzi, while 5-7 displayed moderately potent antiplasmodial activities against Plasmodium falciparum parasites.
Ancistrotanzanine A, the First 5,3‘-Coupled Naphthylisoquinoline Alkaloid, and Two Further, 5,8‘-Linked Related Compounds from the Newly Described Species Ancistrocladus tanzaniensis # ,1
(2003-10) Bringmann, Gerhard; Dreyer, Michael; Faber, Johan H.; Dalsgaard, Petur W.; Staerk, Dan; Jaroszewski, Jerzy W.; Ndangalasi, Henry J.; Mbago, Frank M.; Brun, Reto; Reichert, Matthias; Maksimenka, Katja; Christensen, Søren B.
The first phytochemical investigation of the recently discovered East African liana Ancistrocladus tanzaniensis is described, resulting in the isolation and structural elucidation of two new naphthylisoquinoline alkaloids, ancistrotanzanines A (5) and B (6), and the known compound ancistrotectoriline A (7). Ancistrotazanine A (5) represents a hitherto unprecedented 5,3'-coupling type between the naphthalene and isoquinoline portions, while 6 and 7 are 5,8'-coupled. The structures of the compounds were determined by spectroscopic, chemical, and chiroptical methods. Compounds 5 and 6 showed good activities against the pathogens of leishmaniasis and Chagas' disease, Leishmania donovani and Trypanosoma cruzi, while 5-7 displayed moderately potent antiplasmodial activities against Plasmodium falciparum parasites.
Ancistrotanzanine C and Related 5,1‘- And 7,3‘-Coupled Naphthylisoquinoline Alkaloids From Ancistrocladus T Anzaniensis 1
(2004-05) Bringmann, Gerhard; Dreyer, Michael; Faber, Johan H.; Dalsgaard, Petur W.; Staerk, Dan; Jaroszewski, Jerzy W.; Ndangalasi, Henry J.; Mbago, Frank M.; Brun, Reto; Christensen, Søren B.
Three new naphthylisoquinoline alkaloids, the 7,3'-coupled ancistrotanzanine C (6), the 5,1'-coupled O-methylancistrocladinine (7), and the likewise 5,1'-coupled O,N-dimethylancistrocladine (8, previously known only as a partial-synthetic compound), have been isolated from the highland liana Ancistrocladus tanzaniensis, along with the two known 7,3'-coupled naphthylisoquinoline alkaloids ancistrocladidine (4) and ancistrotectorine (5). All of the compounds are S-configured at C-3 and bear an oxygen at C-6, and thus belong to the so-called Ancistrocladaceae type, similar to 1-3 previously isolated from this newly discovered plant species. The structural elucidation was achieved by chemical, spectroscopic, and chiroptical methods. The biological activities of the alkaloids against the pathogens causing malaria tropica, leishmaniasis, Chagas' disease, and African sleeping sickness were evaluated.
Aspects Of The Floral and Fruit Biology of Allanblackia Stuhlmannii (CLUSIACEAE), An Endemic Tanzanian Tree
(2009-07) Mathew, Mathayo M.; Munjuga, Moses; Ndangalasi, Henry J.; Cordeiro, Norbert J.
Various economically important tropical tree species are not well known biologically. We studied the floral and fruit biology of Allariblackia stuhlmannii (Clusiaceae), a dioecious tree species endemic to the Eastern Arc Mountains of Tanzania and Kenya that has become the subject of recent interest by the food industry because of the edible oil that can be extracted from the seeds. We characterised qualitative and quantitative similarities and differences between male and female flowers, the flowering and fruiting phenology, and examined the relationship between fruit crop production and tree size, seeds per fruit, and seed number as a function of fruit mass. There was no significant difference in sugar concentration of nectar between male and female flowers, but male flowers contained significantly more nectar than female flowers. Male trees had larger flowering displays with a tendency for the population to mast profusely between January and March, which coincided with the peak fruiting period. The fruiting period was pronounced from January to March, which appeared to be preceded by a smaller peak in October. Fruit crop was strongly related to tree size, with mean seed number per fruit being 38. Seed quantity per fruit showed a trend to increase with fruit mass, but this relationship was not significant. General physical resemblance of female flowers to male flowers, the latter of which offer multiple floral cues to attract pollinators, suggests a pollination-by-deceit strategy. Our results provide important insights on the natural history of this tree species and carry implications for its future use.
Assessment on Diversity, Distribution and Management of Cassytha Species in Cashew Growing Areas in Tanzania
(2012) Buriyo, Amelia S.; Moshi, Heriel N.
Back to Africa: Monitoring Post-Hydropower Restoration to Facilitate Reintroduction Of An Extinct-In-The-Wild Amphibian
(2014-08) Vandvik, Vigdis; Måren, Inger E.; Ndangalasi, Henry J.; Lovett, Jon C.
Monitoring of the ecological efficiency of different restoration and mitigation measures is important to inform decision-making but can be challenging, especially in remote and low-resource settings. Species composition of the vegetation is sensitive to environmental variation, and can thus be used in restoration assessment, but this requires statistical approaches that can accommodate multivariate responses. We use principal response curves (PRC) to assess the efficiency of post-hydropower mitigation measures installed to secure the reintroduction of an extinct-in-the-wild amphibian back into its only native habitat. The endemic ovoviviparous Kihansi spray toad Nectophrynoides asperginis is only known from a wetland in the Lower Kihansi River Gorge in the Eastern Arc Mountains in Tanzania. River flow was diverted from the gorge for hydropower production in 1999, causing the spray wetland to desiccate, consequently threatening the toad and other plant and animal species dependent on the spray-zone habitat. To mitigate the toad population collapse, a sprinkler system was installed over a limited section of the original sprayzone wetlands to mimic the waterfall spray and toads were taken to the USA for ex situ breeding. The decline, extinction, ex situ breeding, and planned reintroduction of the species has driven substantial research on Kihansi spray toad biology. In contrast, the efficiency of the mitigation measures in restoring the spray-zone wetland habitat required for its successful reintroduction has not been formally evaluated. Here, we analyze re-sampled vegetation data from the spray-zone wetland over a period of eight years by means of principal response curves to investigate if the post-hydropower mitigation measures have successfully restored the pre-hydropower ecosystem. The results show that the spray-zone vegetation is recovering. The wetland flora and especially species important to the Kihansi spray toad have increased and the restored ecosystem has stabilized, favoring the reintroduction of the Kihansi spray toad to its native habitat. However, the wetland ecosystem is not restored entirely and continued mitigation measures are needed. Continued monitoring is essential to support evidence-based restoration, and we conclude that assessment based on vegetation monitoring coupled with principal response curve analyses provides a cost-effective and efficient monitoring tool for such proje
Back To Africa: Post Hydropower-Project Mitigation Effects on Wetland Vegetation in Relation To The Conservation of an Endemic Amphibian
(Wiley, 2012-07) Maren, Inger E.; Vandvik, Vigdis; Ndangalasi, Henry J.; Taplin, James; Mbago, Frank; Lovett, Jon C.
Developing countries are home to much of the world’s biodiversity due to their location in areas of high species richness and their native vegetation has not yet been totally transformed by human activity. Enabling economic and social development to proceed whilst retaining the high environmental values is central to the principle of sustainability, but activities under these three pillars of sustainability are often in conflict. Provision of energy from environmentally sound technologies is critical for economic development in Africa and hydropower offers a reliable way of doing this. The Lower Kihansi Hydropower Project in Tanzania is a model example of the application of technology to minimise environmental impact. However, although the footprint of the project is relatively small, it is located in a biodiversity hotspot where almost any development will have negative impacts on its many restricted range species. Globally, hydropower projects have been associated with negative biological impacts of flooding of the reservoir impounded by the dam. Less attention has been paid to the immediate downstream effects of dams, such as the loss of waterfall spray zones. We analysed the effects of the mitigation efforts by the installment of a sprinkler system to prevent extinction of the Kihansi Spray Toad Nectophrynoides asperginis, which is only known from this short section of the Kihansi River. We analysed re-sampled vegetation plots in the spray wetland habitat over a period of eight years to test if the post-hydropower project mitigation has aided the vegetation composition in approaching similarity to that of the pre-hydropower project conditions, testing two hypotheses dealing with habitat responses to the mitigation measures; (i) Does the instalment of the sprinkler system alter plant species composition in the former waterfall spray zone in relation to the controls? (ii) Do the mitigation measures succeed in restoring the wetland habitat and hence facilitate the re-introduction of the Kihansi Spray Toad? The results clearly show that the post-hydropower mitigations are successful as the vegetation cover and species composition with time approach that of the pre-hydropower project conditions. Overall, the proportion of weedy species decreased and wetland species increased with time since mitigation. However, results suggest that the wetland has not entirely reverted back to pre-project conditions and continued mitigation measures are needed. In conclusion, this positive trend in the wetland habitat development due to the mitigation measures may facilitate the reintroduction of the in situ extinct Kihansi Spray Toad in the near future.
Comparing Flow Regime, Channel Hydraulics and Biological Communities to Infer Flow-Ecology Relationships in the Mara River of Kenya and Tanzania
(2014) McClain, Michael E.; Subalusky, Amanda L.; Anderson, E.; Dessu, Shimelis B.; Melesse, Assefa M.; Ndomba, Preksedis M.; Mtamba, Joseph O. D.; Tamatamah, Rashid A.; Mligo, Cosmas
Equatorial rivers of East Africa exhibit unusually complex seasonal and inter-annual flow regimes, and aquatic and adjacent terrestrial organisms have adapted to cope with this flow variability. This study examined the annual flow regime over the past 40 years for three gauging stations on the Mara River in Kenya and Tanzania, which is of international importance because it is the only perennial river traversing the MaraSerengeti ecoregion. Select environmental flow components were quantified and converted to ecologically relevant hydraulic variables. Vegetation, macroinvertebrates, and fish were collected and identified at target study sites during low and high flows. The results were compared with available knowledge of the life histories and flow sensitivities of the riverine communities to infer flow–ecology relationships. Management implications are discussed, including the need to preserve a dynamic environmental flow regime to protect ecosystems in the region. The results for the Mara may serve as a useful model for river basins of the wider equatorial East Africa region.
Conservation of Plant Biodiversity of Namatimbili Forest in the Southern Coastal Forests of Tanzania
(2015) Mligo, Cosmas
The aim of this study was to determine the ecological characteristic of Namatimbili Forest in terms of plant species composition, stem size class structure, stand biomass, diversity, and distribution and identify endemic and threatened plant species that are found within the forest. Data were sampled by using transect method that were established in various habitats within the forest. A total of 312 plant species were found in 62 families, where Fabaceae (51 species) was the highly represented of all families. Of all plant species recorded, 26 are cited under IUCN red list and 36 are endemic species of East African Coastal Forests.The woodlands were more diverse with a Shannon’s index of 2.72 ± 0.21 followed by the riverine forest (1.64 ± 0.19), coral rags (2.28 ± 0.32) and closed canopy evergreen forest (2.32± 0.17) and this pattern was also applied to the species evenness and the difference among vegetation types was significant. The DCA ordination revealed a major variation at DCA-Axis1 where samples from riverine forest separated quite clearly and positioned on the right side of the ordination space. The coral rag habitat extended widely overlapping with other habitats because of high similarity in plant species composition. The woodland habitats separated from the evergreen forest habitat at DCA Axis 3 because of plant species composition differences between them, such that closed canopy trees and the understorey species characterized the evergreen habitats. The riverine forest had a density of 136 stems/ha with the DBH sizes between 41 and 292.99 cm and the stand biomass ranged from 0.1 to 876.06 m3/ha. However, high density of trees with DBH sizes beyond 90 cm was observed in the riverine forest, regardless of all the vegetation typeshaving individual stems beyond this size class. The coral rag vegetation had 42 stems/ha, with diameter at breast height (DBH) sizes ranging from 41 to 95.5 cm and stand biomass in a range from 0.1 to 59 m3/ha. The woodlands had 28 stems/ha with the DBH sizes between 41 and 77.38 cm with denser stems at the size class of 10-14 cm DBH and stand biomass in a range from 0.06 to 127.4 m3/ha. There were 31 stems/ha in the evergreen forest with the DBH sizes from 41.40 to 108.28 cm and stand biomass between 0.06 and 64.42 m3/ha. A significant difference exists in stand biomass, basal area, but no difference in crown cover among vegetation types. It can be concluded that, the heterogeneous habitat characteristics in Namatimbili Forest favour the performance of diverse plant species and determine their natural distribution patterns. Large proportion of plant species found in the forest is endemic to the East African Coastal Forests and some of these have been cited under various IUCN threat categories. However, exploitation of timber trees, fire, and clearance for cultivation negatively affected the plant species diversity, distribution and vegetation community structure in this forest. Based on the ecological importance of Namatimbili Forest, the forest need to be considered for gazetting for protection from habitat degradation caused by anthropogenic activities and it should be included in the natural resource management plans of the southern coastal forests of Tanzania.
Correspondence in Forest Species Composition Between The Vegetation Map Of Africa And Higher Resolution Maps For Seven African Countries
(2013-12) Kindt, Roeland; Lillesø, Jens-P. B.; Breugel, Paulo V.; Dudley, C.; Gachathi, Francis; Demissew, Sebsebe; Kalema, James
Correspondence in Forest Species Composition Between The Vegetation Map of Africa And Higher Resolution Maps For Seven African Countries
(Wiley, 2013-12) Kindt, Roeland; Lillesø, J. P. B.; van Breugel, Paulo; Bingham, M.; Demissew, Sebsebe; Dudley, C.; Gachathi, Francis; Kalema, James; Mbago, Frank M.
Correspondence in Forest Species Composition Between The Vegetation Map Of Africa And Higher Resolution Maps For Seven African Countries. Applied Vegetation Science. Article First Published Online:
(Wiley, 2012-12) Kindt, Roeland; Lillesø, Jens-Peter B.; Breugel, Paulo V.; Bingham, M.; Demissew, Sebsebe; Dudley, C.; Friis, I.; Gachathi, Francis; Kalema, James; Mbago, Frank; Moshi, Heriel N.; Mulumba, John W.; Namaganda, Mary; Ndangalasi, Henry J.; Ruffo, Christopher K.; Minani, Védaste; Jamnadass, Ramni H.; Graudal, Lars
Question How well does the forest classification system of the 1:5,000,000 vegetation map of Africa developed by Frank White correspond with classification systems and more extensive information on species assemblages of higher resolution maps developed for Ethiopia, Kenya, Malawi, Rwanda, Tanzania, Uganda and Zambia? Methods We reviewed various national and sub-national vegetation maps for their potential in increasing the resolution of the African map. Associated documentation was consulted to compile species assemblages, and to identify indicator species, for national forest vegetation types. Indicator species were identified for each regional forest type by selecting those species that, among all the species listed for the same phytochorion (regional centre of endemism), were listed only for that forest type. For each of the national forest types, we counted the number of indicator species of the anticipated regional type. Floristic relationships (expressed by four different ecological distance measures) among national forest types were investigated based on distance-based redundancy analysis, permutational multivariate analysis of variance (PERMANOVA) using distance matrices and hierarchical clustering.
Cross Compatibility of Cultivars of Gossypium Hirsutum L. and Feral Gossypium Barbadense L. in the Southern Highlands of Tanzania
(2012-12) Shilla, O.; Hauser, T. P.; Tibazarwa, Flora I.
Cotton is the second most important cash crop contributing about 15% to the annual foreign earning in Tanzania and is purely from Gossypium hirsutum L. cultivars. Gossypium barbadense L., a textile source in other parts of the world occurs as a feral perennial of ornamental and medicinal value in home gardens. G. barbadense L. is a natural host of the red bollworm, a destructive pest to cotton. The Southern Highlands (SH) of Tanzania have been quarantined from cotton production to control spread of the red bollworm to other growing areas. Transgenic cotton expressing the delta-endotoxin genes from Bacillus thuringiensis (Bt) offers an alternative control to the pest and reduced dependence on insecticide. Gene flow between wild or valued feral relatives and transgenic crops is a biosafety concern should transgene escape result in resistance development and contamination of germplasm. Potential gene flow between feral G. barbadense (including accessions Gb1 and Gb2) from the SH and G. hirsutum cultivars was assessed using controlled hybridization. The crosses produced fertile F1 but intraspecific seeds from G. barbadense did not germinate. G. barbadense is more likely to receive than donate genes implying development of pest resistance if introgressed filial generations express the Bt product.
Determinants of Woody Cover in African Savannas
(2005) Sankaran, Mahesh; Hanan, Niall P.; Scholes, Robert J.; Ratnam, Jayashree; Augustine, David J.; Cade, Brian S.; Gignoux, Jacques; Higgins, Steven I.; Le Roux, Xavier; Ludwig, Fulco; Ardo, Jonas; Banyikwa, Feetham F.; Bronn, Andries; Bucini, Gabriela; Caylor, Kelly K.; Coughenour, Michael B.; Diouf, Alioune; Ekaya, Wellington; Feral, Christie J.; February, Edmund C.; Frost, Peter G. H.; Hiernaux, Pierre; Hrabar, Halszka; Metzger, Kristine L.; Prins, Herbert H. T.; Ringrose, Susan; Sea, William; Tews, Jörg; Worden, Jeff; Zambatis, Nick
Savannas are globally important ecosystems of great significance to human economies. In these biomes, which are characterized by the co-dominance of trees and grasses, woody cover is a chief determinant of ecosystem properties1, 2, 3. The availability of resources (water, nutrients) and disturbance regimes (fire, herbivory) are thought to be important in regulating woody cover1, 2, 4, 5, but perceptions differ on which of these are the primary drivers of savanna structure. Here we show, using data from 854 sites across Africa, that maximum woody cover in savannas receiving a mean annual precipitation (MAP) of less than ~650 mm is constrained by, and increases linearly with, MAP. These arid and semi-arid savannas may be considered ‘stable’ systems in which water constrains woody cover and permits grasses to coexist, while fire, herbivory and soil properties interact to reduce woody cover below the MAP-controlled upper bound. Above a MAP of ~650 mm, savannas are ‘unstable’ systems in which MAP is sufficient for woody canopy closure, and disturbances (fire, herbivory) are required for the coexistence of trees and grass. These results provide insights into the nature of African savannas and suggest that future changes in precipitation6 may considerably affect their distribution and dynamics.
Determination of the Soil Organic Carbon, Nitrogen, Available Phosphorus and the Combined Aboveground Plant Materials in the Semi‐Arid Mbulu District, Tanzania
(2009) Mligo, Cosmas
Soil of the semi-arid Mbulu District is part of the tropical soils, covered with sparse trees, shrubs or grasses in which domestic grazing animals have prevented the wide spread of vegetation cover. The study aimed at determining soil organic carbon (OC), total nitrogen (N), available phosphorus (P) and the combined aboveground plant materials. Six study sites were established in which soil samples were collected at the depths of 0–5, 6–10 and 11–20 cm. Soil samples were analysed for OC, N and P as well as the levels of N and P in the combined aboveground materials of Panicum coloratum and Hyparrhenia filipendula. The percentage concentrations of OC, N and P were high in the top soil than in the deeper soil horizons. However, analysis of variance showed significant differences of OC in some sites whereas no difference for N and P between soil depth classes. OC was highly related with N and P along soil depth classes. It was concluded that the availability of N and P was because of the decomposition of organic matter in the soil. Soil N and P were highly related with the same in the combined aboveground plant materials. It was concluded that the increased concentration of N and P in the soil resulted into availability of the same in P. coloratum and H. filipendula. There was a very high variation in N and P among sites with different levels of intensity of grazing. It was concluded that grazing animals contributes to the redistribution of soil elements in the rangelands because they graze upon plant parts but the excreta are dropped away from the grazed spot.
Developing the Environmental Long-Term Observatories Network of Southern Africa (ELTOSA)
(2003-04) Henschela, Joh; Pauw, Johan; Banyikwa, Feetham F.; Brito, Rui; Chabwela, Harry; Palmer, Tony; Ringroseg, Sue; Santos, Luisa; Sitoed, Almeida; Jaarsveld, Albert V.
Background In May 2001, we, scientists from six countries in southern Africa, formed the Environmental Long-Term Observatories Network of Southern Africa (ELTOSA). Further development was made at the ELTOSA conference on Inhaca Island, Mozambique, during July 2002. ELTOSA connects country Environmental Observatories Networks (EON), the African adaptation of LTER (long-term ecological research). The International Long-Term Ecological Research Network (ILTER) has accepted ELTOSA as a regional member, and currently three ELTOSA country members have individual ILTER membership (Namibia in 1999, Zambia in 2001, South Africa in 2002) and others are working towards membership. This position paper describes the development of a vision for EON in southern Africa. We outline the importance of developing EON and list the opportunities this offers for the natural and social sciences. Finally, we focus on some challenges that accompany the development of EON in the region, with suggestions on how to meet them.
Developing the Environmental Long-Term Observatories Network of Southern Africa (ELTOSA)
(2003) Henschel, Joh; Pauw, Johan; Banyikwa, Feetham F.; Brito, Rui; Chabwela, Harry; Palmer, Tony; Ringrose, Sue; Santos, Luisa; Sitoe, Almeida; van Jaarsveld, Albert
In May 2001, we, scientists from six countries in southern Africa, formed the Environmental Long-Term Observatories Network of Southern Africa (ELTOSA). Further development was made at the ELTOSA conference on Inhaca Island, Mozambique, during July 2002. ELTOSA connects country Environmental Observatories Networks (EON), the African adaptation of LTER (long-term ecological research). The International Long-Term Ecological Research Network (ILTER) has accepted ELTOSA as a regional member, and currently three ELTOSA country members have individual ILTER membership (Namibia in 1999, Zambia in 2001, South Africa in 2002) and others are working towards membership. This position paper describes the development of a vision for EON in southern Africa. We outline the importance of developing EON and list the opportunities this offers for the natural and social sciences. Finally, we focus on some challenges that accompany the development of EON in the region, with suggestions on how to meet them.
Diet Of The Silvery-Cheeked Hornbill Bycanistes Brevis During the Breeding Season in The East Usambara Mountains, Tanzania
(Taylor & Francis, 2016-01) Cordeiro, Norbert J.; Campbell, Joshua T; Ndangalasi, Henry J.
The breeding season diet and nesting characteristics of the Silvery-cheeked Hornbill Bycanistes brevis are poorly known. To further understand these aspects of the breeding biology of this hornbill species, 14 nests were studied in and around Amani Nature Reserve located in the East Usambara Mountains, Tanzania. Nesting tree species were identified and the diet composition of nesting hornbills was evaluated between July and November 2001. The ejecta from each nest were collected, inventoried, identified (as completely as possible) and enumerated. Food items were categorised as plant, vertebrate or invertebrate. Plants, represented largely by fruits, were the dominant food type (n = 861), followed by invertebrates (n = 306; mainly millipedes and beetles), and vertebrates (n = 15; mainly smaller birds and chameleons). A comparison of results from the current study to other nesting observations made approximately seven decades earlier in the same area suggest that (1) the invasive tree species Maesopsis eminii, which was the most common food type consumed (n = 4 539 seeds), has become a favoured new food source in the breeding season, and (2) the breeding season appears to have shifted to an earlier period, potentially due to the fruiting phenology and abundance of Maesopsis eminii.

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