首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
A minute new species of Kyllinga, i.e. K. carinalaevis Lye & Mesterházy, from Benin in west tropical Africa is described. It is one of three or four annual species of the genus, and the characters separating it from two other annual species are given. The species is ephemeral and occurs in a vegetation type which belongs to a Nanocyperion association. The species is probably critically endangered as it was found in a single locality out of the numerous sites that have been investigated in Benin in recent years.  相似文献   

3.
We performed a terrestrial small mammal species inventory in the Agoua and Wari‐Maro forest reserves (Benin). Four localities were sampled, and in each locality, three habitats were surveyed: dense forest, open forest or woodland savannah and shrub savannah. This is the first comprehensive inventory for small mammals in central Benin. We captured 794 small mammals representing twenty species (six shrew species, fourteen rodent species). Three new species that need to be described were recorded. We observed a mixture of both true forest species and of species adapted to a wider range of habitats ranging from savannah to forest clearings. Species with either Sudanian or Guinea–Congolian affinities were recorded, as well as a new species endemic to Togo and Benin. This rich biodiversity underlines the urgent need for an effective protection of these forests. The Sudanian species Crocidura cf. foxi was more abundant in Wari‐Maro than in Agoua forest, while the Guineo–Congolian species Praomys misonnei and Hylomyscus sp were only captured in Agoua forest. These results are in agreement with the fact that these two forests belong to two distinct chorological zones.  相似文献   

4.
Of the eight Cantharellus species known from Benin, seven have been encountered under similar macroecological conditions. The present work attempts to generate a more complete distribution of these seven species. Forty-eight occurrences of the target species and four explanatory variables including three bioclimatic variables and a land cover variable were used to build an ensemble model from five modelling approaches under the Biomod2 package of R software. Results showed a distribution restricted to the Bassila and Atacora mountain range phytogeographic districts with excellent statistical performance (TSS = 0.98, AUC = 0.99). This distribution is governed mainly by high soil moisture and high potential evapotranspiration, thus defining only gallery forests as the most suitable habitat for chanterelles in Sudano-guinean and Soudanese ecozones of Benin. Based on IUCN criterion B1 and sub-criteria B1a and B1c(i), these seven species were categorized under the Endangered (EN) threat category according to our results.  相似文献   

5.
Sites in the humid forest of Cameroon and the derived savanna of Benin were selected to evaluate the effect of planting border rows of wild host plants on lepidopterous stem-borer infestations and on maize yield. Grass species were chosen that in surveys and greenhouse trials were highly attractive to ovipositing female moths but with offspring mortality of close to 100%, thus acting as trap plants. In Cameroon, elephant grass Pennisetum purpureum Moench significantly lowered infestations of Busseola fusca (Fuller), Sesamia calamistis Hampson and Eldana saccharina Walker and increased yields of maize though the differences were not significant during all three cropping seasons. In 1998 in Benin, the only grass tested, Pennisetum polystachion L., significantly increased parasitism of mainly S. calamistis eggs by Telenomus spp. and larvae by Cotesia sesamiae Cameron and reduced numbers of the cob-borer Mussidia nigrivenella Ragonot. In 1999, three grass species; P. polystachion, Sorghum arundinaceum (Desv.) Stapf and Panicum maximum Jacq. were tested. Panicum maximum was the most efficient species for suppressing S. calamistis and M. nigrivenella infestations and enhancing egg and larval parasitism. In the Benin trials, with the exception of M. nigrivenella damage to cobs, the grass species tested had no beneficial effect on yield because pest densities were too low and also rodent damage to maize was enhanced with grasses in the vicinity of the crop. By contrast, stand losses due to Fusarium verticillioides Sacc. (Nirenberg), were significantly reduced by border rows of grasses.  相似文献   

6.
Abstract  The seasonal fluctuation of lepidopteran cereal stemborers on maize and wild host plants (i.e., grasses and a few sedges) was investigated in southern Benin from 1988 to 1998 by time series analysis and repeated-measures analysis of variance (ANOVA). In addition, a walk-in light trap was used to study the flight behavior of adult moths. On both cereals and grasses, the noctuid Sesamia calamistis was the predominant species, followed by the pyralid Eldana saccharina . The noctuid Busseola fusca was rare on both maize and wild host plants. In general, pest populations increased during the course of the year to reach peak densities during the second short rainy season, and then crashed to close to zero during the dry season. On wild host plants, egg masses and other immature stages were collected throughout the year but they were higher on wild grasses than maize during the off-season. Thus wild host plants can be considered as refuge for both borers and natural enemies during the off-season, when maize is not available. However, only four out of the eleven wild host species played a discernable role. S. calamistis egg densities appeared to be influenced by density-dependent factors, suggesting an effect of natural enemies. Temperature and rainfall had a negative effect on egg abundance. Larval parasitism by a Kenyan strain of the braconid Cotesia sesamiae , which was released in southern Benin in the early 1990s, and by the tachinid Sturmiopsis parasitica varied between seasons and years but there were no discernable patterns. For both parasitoids and borer host species, parasitism was positively correlated with trap catches of adult moths. The recovery of C. sesamiae during a 2-year period suggests that the parasitoid has established its population in southern Benin.  相似文献   

7.
The spotted-necked otter (Lutra maculicollis) is believed to be declining across its range and, in Benin, has recently been listed as endangered. In Benin, the spotted-necked otter is largely restricted to the south of the country, where it is threatened by a number of factors, including conflict with fishermen. Understanding the nature and extent of this conflict, and the impact that it has on local fishermen, as well as identifying feasible mitigation strategies, represents a critical challenge for conservation managers.This study documents otter damage experienced by 30 fishermen in the Hlan River, in the Southern Benin wetlands. We performed hierarchical classification analysis using Ward distances to categorize fish species according to the level of otter damage suffered, and used generalized linear models to identify predictors that best explained otter damage. Our results suggest that of the 16 fish species commonly caught by fishermen in the Hlan River, otters favored the most valuable species (but these were also the most abundant in the catch). However, although otter damage was extensive, monthly total income loss attributable to spotted-necked otter damage (including fish loss and damage to equipment) was estimated at only 9% per fishermen (considerably lower than the 30% reported by a preliminary survey of 163 fishermen in the same area). Our model showed that otter damage increased significantly with the number of adult fish captured by fisherman while the cost of otter damage increased with the length of time that the fishing equipment was left unattended. We suggest that otter damage could be reduced if fishing equipment were checked at least twice a day by fishermen, and recommend a maximum interval between checks of 700 min (12 h). Long-term sustainable management of these conflicts will require an integrated approach taking into account socio-economic, political and environmental dimensions.  相似文献   

8.

Background

One of the main obstacles for the mainstreaming of religious traditions as tools for the conservation of nature is the limited applicability of research results in this field. We documented two different restrictions implemented by local people (taboos and sacrifices) related to the use of ritual plants in Benin (West Africa) and Gabon (Central Africa).

Methods

To see whether these restrictions reflected plant scarcity from an etic perspective (official threat status) and an emic viewpoint (perceived scarcity by local people), we conducted 102 interviews with traditional healers and adepts of traditional faiths.

Results

We documented a total of 618 ritual plants, from which 52 species were used in both countries. In Benin, the use of 63 of the 414 ritual plant species was restricted; while in Gabon 23 of the 256 ritual plants were associated with taboos and sacrifices. In Benin, restricted plants were significantly more often officially threatened, perceived as scarce, and actively protected than non-restricted plants. In the more forested and less densely populated Gabon, plants that were perceived as scarce were more often associated to local restrictions than officially threatened species.

Conclusions

These results prove the presence of a form of adaptive management where restrictions are related to resource scarcity and protection of ritual plant species. By providing baseline data on possibly endangered species, we demonstrate how plant use in the context of religious traditions can yield important information for conservation planning.

Electronic supplementary material

The online version of this article (doi:10.1186/1746-4269-11-5) contains supplementary material, which is available to authorized users.  相似文献   

9.
Plankton hauls were made with 55 m Hydrobios nets at one Jamieson and six Benin River stations at monthly intervals for 12 and 24 months during 1981/82 and 1986–1988, respectively. In all, a 100 km stretch of the Benin River and its tributary, the Jamieson, were covered. Fifty species of Rotifera were recorded. About 80% were cosmopolitan. The turbulent nature of the river is reflected in a diversity of Lecanidae found, although the dominant species were Keratella tropica (Apstein) and Keratella cochlearis (Gosse) (Brachionidae). Spatial investigations revealed the euryhaline nature of Brachionus plicatilis (O. F. Muller), and showed most Benin River rotifers to be freshwater inhabitants.  相似文献   

10.
《Cytokine》2014,65(2):217-221
The chronic inflammatory state in sickle cell anemia (SCA) is associated with several factors such as the following: endothelial damage; increased production of reactive oxygen species; hemolysis; increased expression of adhesion molecules by leukocytes, erythrocytes, and platelets; and increased production of proinflammatory cytokines. Genetic characteristics affecting the clinical severity of SCA include variations in the hemoglobin F (HbF) level, coexistence of alpha-thalassemia, and the haplotype associated with the HbS gene. The different haplotypes of SCA are Bantu, Benin, Senegal, Cameroon, and Arab-Indian. These haplotypes are associated with ethnic groups and also based on the geographical origin. Studies have shown that the Bantu haplotype is associated with higher incidence of clinical complications than the other haplotypes and is therefore considered to have the worst prognosis. This study aimed to evaluate the profile of the proinflammatory cytokines interleukin-6, tumor necrosis factor-α, and interleukin-17 in patients with SCA and also to assess the haplotypes associated with beta globin cluster S (HBB*S). We analyzed a total of 62 patients who had SCA and had been treated with hydroxyurea; they had received a dose ranging between 15 and 25 (20.0 ± 0.6) mg/kg/day for 6–60 (18 ± 3.4) months; their data were compared with those for 30 normal individuals. The presence of HbS was detected and the haplotypes of the beta S gene cluster were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Our study demonstrated that SCA patients have increased inflammatory profile when compared to the healthy individuals. Further, analysis of the association between the haplotypes and inflammatory profile showed that the levels of IL-6 and TNF-α were greater in subjects with the Bantu/Bantu haplotype than in subjects with the Benin/Benin haplotype. The Bantu/Benin haplotype individuals had lower levels of cytokines than those with the Bantu/Bantu haplotype and greater levels than those of subjects with the Benin/Benin haplotype. For IL-17, a slight trend toward decreased levels was observed in the subjects with the Benin/Benin haplotype, when compared to those with the Bantu/Bantu and Bantu/Benin haplotypes; however, this difference was not statistically significant. Our results show that genetic polymorphisms in sickle cell anemia are associated with the inflammatory profile.  相似文献   

11.
Estimating the Local Value of Non-Timber Forest Products to Pendjari Biosphere Reserve Dwellers in Benin. This paper uses an indices method based on participant ranking of species to quantify use–values of Non-Timber Forest Products (NTFPs) and the socio-economic factors that influence these values for people living around the Pendjari Biosphere Reserve in Benin. There were 76 species identified that had a high index value to people. The 10 most valued species were Parkia biglobosa, Adansonia digitata, Vitellaria paradoxa, Tamarindus indica, Lannea microcarpa, Vitex doniana, Hibiscus asper, Melochia corchorifolia, Khaya senegalensis, and Diospyros mespiliformis. Species values were influenced by the vegetative form of the species as well as by the gender of a participant and his/her affiliation to the ethnic group. The study also illustrates that women had a preference for NTFP species with high commercial and nutritional values, while men preferred plants that provide construction material and medicine. Moreover, the ethnic group that historically had more contact and interaction with the vegetation valued NTFPs more than any other group. The difference in value attributed to species by people was also driven by the vertical transmission of ethnobotanical knowledge in the study area. For long-term biodiversity conservation, it will be useful to involve the needs of all of the local communities in the design of a management plan and focus attention on the most important species.  相似文献   

12.
Abstract: Extensive collections of Teretrius nigrescens in Mexico, Honduras, and Benin, were electrophoretically analysed to elucidate the prey spectrum of the predator. Both polyacrylamide gel electrophoresis and cellulose acetate electrophoresis were used. Beetles were sampled with pheromone traps, using the synthetic aggregation pheromone of Prostephanus truncatus , and directly from farmers' maize stores. The proportion of electrophoretically detected prey protein from adult T. nigrescens in pheromone traps was low: of the 1108 specimens analysed, only in 34 cases, prey protein could be clearly identified. More frequently, prey protein was detected in adult T. nigrescens sampled in maize stores in Mexico, Honduras, and Benin, with 87 samples showing distinct prey bands of the total 1214 predators analysed. Of the 241 T. nigrescens larvae sampled in maize stores in Benin, 136 showed distinct bands of prey protein. In all samples, P. truncatus was the most frequently detected prey species. The second most often identified prey species was Sitophilus zeamais . The results are discussed with regard to various methods for prey spectrum analysis and specifically the biology of T. nigrescens .  相似文献   

13.
This paper examines the contribution of human migrations to the propagation and maintenance of Caesalpina bonduc by means of an analysis of its population genetics and distribution patterns. One hundred and forty seven sites were surveyed in the three climatic zones of Benin and all individuals of the species were recorded. A set of individuals was randomly selected and sampled from seven populations and morphological variation and genetic diversity were assessed. The study confirmed the presence of the species in all climatic zones but its abundance varied greatly. Morphological variability between populations and zones was low in comparison with the high amount of variation within populations. AFLP and cpDNA fingerprinting revealed an extremely low genetic diversity within populations and a low genetic differentiation, suggesting parental links between populations. The results support the hypothesis of human involvement in Caesalpinia dispersal and persistence in Benin. However, the low genetic diversity may imply high risks for future extinction. We recommend that gene flow among the remaining populations be supported in order to conserve the species.  相似文献   

14.
Adjakpa, J.B. 2000. The breeding biology of Abdim's Stork Ciconia abdimii in the far north of Benin. Ostrich 71 (1 & 2): 61–63.

Little is known about the biology of Abdim's Stork Ciconia abdimii, in Benin. I studied the nesting of this intra- African migrant in the wet season of 1996. Breeding pairs arrived at the end of March 1996. Seven nest sites were found, involving 92 pairs; the largest colony was of 51 pairs. The storks used five different large tree species for nesting. Egg-laying began in early April and lasted until 2 July. Most clutches were of 3–4 eggs. Incubation lasted 28–29 days. A total of 196 young storks fledged (all of which were ringed), representing a success rate of 76.5% per egg laid and 86.0% per egg hatched. The last storks left the colonies on 9 September 1996, 164 days after the first ones arrived on 30 March. The species is threatened in Benin by human persecution and by widespread pesticide use: it urgently requires official protected status.  相似文献   

15.
Ackee (Blighia sapida) is a native multipurpose species important for the livelihoods of the rural populations in Benin. Trees are found in natural forests or are managed by farmers in different traditional agroforestry systems. Genetic variation at amplified fragment length polymorphism (AFLP) markers, four nuclear microsatellites (nSSRs) and one chloroplast microsatellite (cpSSR) were investigated in 279 individuals from six wild and eight cultivated populations from Benin. The AFLP data revealed moderate levels of diversity of ackee in Benin (mean diversity values are proportion of polymorphic loci = 52.8% and Nei??s gene diversity = 0.157, for 375 AFLP fragments). The mean diversity values based on nSSR-markers are expected heterozygosity = 0.286, allelic richness = 2.77. Genetic variation of wild and cultivated populations did not differ markedly. AMOVA revealed that only 7.3 and 5.2% of the variation was partitioned among populations for nSSR- and AFLP-markers, respectively. A Mantel test based on these both marker-types revealed significant correlations between population pairwise geographic distance and genetic differentiation. Differentiation among cultivated populations was higher than among wild populations. The only polymorphic chloroplast microsatellite marker (ccmp7) showed three haplotypes. Cultivated populations from northeastern Benin were fixed on one haplotype which was not observed elsewhere indicating a different origin of these populations possibly from neighboring Nigeria. Farmer-led domestication had an impact on the spatial distribution of genetic variation but did not result in significant losses of diversity within populations. Measures to conserve genetic resources of ackee in each of the three main bioclimatic zones in Benin are proposed.  相似文献   

16.
Diversity, Geographical, and Consumption Patterns of Traditional Vegetables in Sociolinguistic Communities in Benin: Implications for Domestication and Utilization. Traditional vegetables in many African rural areas are an important part of the daily diet and economy but have been poorly documented until recently. We undertook a survey in Benin on the diversity and patterns of use of traditional vegetables by 18 sociolinguistic groups in the three major phytogeographical regions. Major groups include the Yoruba–Nagot, Fon, Bariba, Adja, Cotafon, and Ditammari. Focus groups and field visits were conducted in 49 villages. Species richness at the country level and in phytogeographical regions was estimated using species accumulation curves. Our results indicated that 245 species belonging to 62 families are used as vegetable resources all over the country. The most frequently used families include Amaranthaceae, Asteraceae, Cucurbitaceae, and Leguminoseae. About 80% of collected vegetables are wild resources; only 19% were clearly under cultivation. Herbs were the most widely consumed life form. The Guinean and the Sudanian regions exhibit similar species richness while in the Sudano–Guinean region vegetable richness is higher. The use of a species as a vegetable depends not only on socio–cultural attributes but also on geographical occurrence. Based on this inventory, we identified needs for further research and activities for both the conservation and promotion of traditional vegetables.  相似文献   

17.
Few regional or continent-wide assessments of bird use for traditional medicine have been attempted anywhere in the world. Africa has the highest known diversity of bird species used for this purpose. This study assesses the vulnerability of 354 bird species used for traditional medicine in 25 African countries, from 205 genera, 70 families, and 25 orders. The orders most represented were Passeriformes (107 species), Falconiformes (45 species), and Coraciiformes (24 species), and the families Accipitridae (37 species), Ardeidae (15 species), and Bucerotidae (12 species). The Barn owl (Tyto alba) was the most widely sold species (seven countries). The similarity of avifaunal orders traded is high (analogous to “morphospecies”, and using Sørensen''s index), which suggests opportunities for a common understanding of cultural factors driving demand. The highest similarity was between bird orders sold in markets of Benin vs. Burkina Faso (90%), but even bird orders sold in two geographically separated countries (Benin vs. South Africa and Nigeria vs. South Africa) were 87% and 81% similar, respectively. Rabinowitz''s “7 forms of rarity” model, used to group species according to commonness or rarity, indicated that 24% of traded bird species are very common, locally abundant in several habitats, and occur over a large geographical area, but 10% are rare, occur in low numbers in specific habitats, and over a small geographical area. The order with the highest proportion of rare species was the Musophagiformes. An analysis of species mass (as a proxy for size) indicated that large and/or conspicuous species tend to be targeted by harvesters for the traditional medicine trade. Furthermore, based on cluster analyses for species groups of similar risk, vultures, hornbills, and other large avifauna, such as bustards, are most threatened by selective harvesting and should be prioritised for conservation action.  相似文献   

18.
Bowalization is a particular form of land degradation and leads to lateral expansion of ferricrete horizons. The process occurs only in tropical regions. In this study, the most adapted and resistant species towards climate change were identified on bowé. The 15 most common bowé species of the subhumid and semi‐arid climate zones of Benin were submitted together with significant environmental variables (elevation, current bioclimatic variables, soil types) to three ecological niche modelling programmes (Maxent, Domain and GARP). For future prediction (2050), IPCC4/CIAT and IPCC5/CMIP5 climate data were applied. Asparagus africanus, Andropogon pseudapricus and Combretum nigricans were identified as the most resistant species for ecological restoration of bowé in the semi‐arid climate zone and Asparagus africanus, Detarium microcarpum and Lannea microcarpa in the subhumid climate zone. The ‘Pull’ strategies were identified as appropriate for ecological restoration of bowé in Benin.  相似文献   

19.

Background

We undertook ethnobotanical and ecological studies on fodder plants grazed by cattle across Benin national area. The study aims to ascertain the top priority fodder plants in order to catalogue the indigenous knowledge regarding their use.

Methods

Data were collected through semi-structured interviews and covered 690 breeders and 40 days of pasture walk. These were analysed using similarity index of Jaccard (IS), relative frequency citation (RFC) and fodder value during pasture walk (FVPW).

Results

We documented a total of 257 fodder plant species, of which 116 recorded during ethnobotanical investigations and 195 during pasture walk. These species belong to 181 genera and 54 families. Both methods shared 52 species. Leaves (58%) and leafy stem (28%) were the most grazed parts of plant. The most common species used as fodder included Andropogon gayanus, Panicum maximum, Pterocarpus erinaceus and Flueggea virosa. The top species with a highest FVPW were Panicum maximum and Pterocarpus erinaceus. A total of 16 species were considered as top fodder plants in Benin.

Conclusions

The wide diversity of plants reported indicates that there is a number of promising fodder species in the flora of Benin. The insight gained in this study relating to bovine feeds could guide in the selection and introduction of feed innovations that could improve livestock production.
  相似文献   

20.
Non-timber forest products contribute significantly to rural livelihoods in the West African savannas. This study investigates differences in use preferences for native woody species in six categories of plant use and their economic returns among five ethnic groups in Northern Benin. Ethnobotanical survey data from 230 households revealed that both ethnic affiliation and location significantly impact species’ valuation. Of a total of 90 species, 61 % were used for medicinal applications, 41 % as firewood, 39 % for construction, and 32 % as human foods. While certain plant species were used by all rural dwellers, others were used exclusively by particular ethnic groups. Vitellaria paradoxa, Parkia biglobosa and Adansonia digitata are key economic species for all groups. Conservation measures should consider multi-purpose trees fulfilling subsistence and cash needs while taking into consideration cultural differences in use preferences.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号