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1.
Four new species in the hermatypic scleractinian coral genus Acropora art described from southeast Africa. Two species, A. natalensis sp. nov. and A. mossambica sp. nov. , occur in both South Africa and Mozambique. Two species, A. sordiensis sp. nov. , and A. branchi sp. nov. , are only known from northern Natal in South Africa. A. branchi sp. nov. and A. mossambica sp. nov. are intertidal species and were collected from permanent tidal pools. A. sordiensis sp. nov. and A. natalensis sp. nov. are strictly subtidal species.  相似文献   
2.
Invasive species pose a major threat to aquatic ecosystems. Their impact can be particularly severe in tropical regions, like those in northern Australia, where >20 invasive fish species are recorded. In temperate regions, environmental DNA (eDNA) technology is gaining momentum as a tool to detect aquatic pests, but the technology's effectiveness has not been fully explored in tropical systems with their unique climatic challenges (i.e. high turbidity, temperatures and ultraviolet light). In this study, we modified conventional eDNA protocols for use in tropical environments using the invasive fish, Mozambique tilapia (Oreochromis mossambicus) as a detection model. We evaluated the effects of high water temperatures and fish density on the detection of tilapia eDNA, using filters with larger pores to facilitate filtration. Large‐pore filters (20 μm) were effective in filtering turbid waters and retaining sufficient eDNA, whilst achieving filtration times of 2–3 min per 2‐L sample. High water temperatures, often experienced in the tropics (23, 29, 35 °C), did not affect eDNA degradation rates, although high temperatures (35 °C) did significantly increase fish eDNA shedding rates. We established a minimum detection limit for tilapia (1 fish/0.4 megalitres/after 4 days) and found that low water flow (3.17 L/s) into ponds with high fish density (>16 fish/0.4 megalitres) did not affect eDNA detection. These results demonstrate that eDNA technology can be effectively used in tropical ecosystems to detect invasive fish species.  相似文献   
3.
Despite the significant improvements achieved over the last ten years, primary education attainment in Mozambique is still low. Potential reasons acting from the demand perspective include ill health, among other factors. In Mozambique, ill health is still largely linked to malaria, which is a leading cause of outpatient contacts, hospital admissions and death, particularly among under-five and school-aged children. Despite this, in Mozambique and more generally, in malaria endemic countries, the identification and measurement of how improved malaria indicators may contribute to better school outcomes remains largely unknown. In particular, there is a low understanding of the extent to which better health translates immediately into school indicators, such as absenteeism and grades. In this study, we exploit the first year of a malaria elimination initiative implemented in Magude district (Southern Mozambique) that started in 2015, as a quasi-experiment to estimate the impact of malaria on selected primary school outcomes. While malaria was not eliminated, its incidence drastically dropped. We use as control a neighbouring district (Manhiça) with similar socio-economic and epidemiological characteristics. By employing a difference-in-differences (DiD) approach, we examine whether the positive health shock translated into improved school outcomes. Using information from school registers, we generated a dataset on school attendance and grades for 9,848 primary-school students from 9 schools (4 in the treated district and 5 in the control district). In our main specification, a repeated cross-section analysis, we find that the elimination initiative led to a 28% decrease in school absenteeism and a 2% increase in students’ grades. Our results are robust across different specifications, including a panel DiD individual fixed effects estimate on a sub-sample of students. These findings provide evidence on the negative impact of malaria on primary education attainment and suggest remarkable economic benefits consequent to its elimination.  相似文献   
4.
Inhaca Island (southern Mozambique) is located in a high-latitude setting along the seaward margins of the estuarine Maputo Bay and is subject to fluctuations in temperature and salinity, and high sedimentation and turbidity levels. Coral reefs are developed sporadically along the margins of intertidal channels, but framework development is severely restricted. Coral growth is bathymetrically limited (never exceeding 6-m depth), and framework accumulation is only present in the upper 1–2 m. Massive Porites sp. produce a basic reef structure, with other coral genera (mainly Acropora sp., Favia sp., Platygyra sp., Pocillopora sp., and Montipora sp.) colonizing available substrata. Sediment samples also indicate restricted carbonate sediment production, with siliciclastics (mainly quartz) a major sediment contributor (often >90%) and carbonate grain assemblages differing from those normally associated with lower-latitude reefs. Although corals, molluscs and coralline algae (including rhodoliths) represent dominant grain constituents, Halimeda is absent and there is a low diversity (four species identified) of benthic foraminifera (mainly Amphistegina sp.). Grain associations are therefore somewhat transitional in character, comprising elements of both tropical (chlorozoan) and temperate (foramol) grain assemblages. These patterns of reef and associated carbonate production emphasize the marginal character of these reef environments, which form one end member in a broad spectrum of marginal reef systems that are now being identified in a range of both high- and low-latitude settings.  相似文献   
5.
Aim A previous study of the allodapine bee genus Braunsapis suggested an African origin, with dispersal events into Madagascar and Asia, and from Asia into Australia. We re‐examine the phylogeny of this genus, using an expanded set of taxa from Madagascar and Malawi and additional sequence data, in order to determine the number of dispersals and the timeframe over which they occurred. Location Africa, Madagascar, Malawi, Asia and Australia. Methods One nuclear (EF‐1α F2) and two mitochondrial (CO1 and Cyt b) gene regions were sequenced for 36 allodapine bee species (including members of the genera Braunsapis, Nasutapis, Allodape, Allodapula, and Macrogalea) and one ceratinine species (Ceratina japonica). We used Bayesian analyses to examine phylogenetic structure and a penalized likelihood approach to estimate approximate ages for key divergences in our phylogeny. Results Our analyses indicate a tropical African origin for Braunsapis in the early Miocene followed by very early dispersal into Asia and then a subsequent dispersal, following Asian diversification, into Australia during the late Miocene. There have also been two dispersals of Braunsapis from Africa to Madagascar and this result, when combined with phylogenetic and biogeographical data for other allodapines, suggests that these bees have the ability to cross moderately large ocean expanses. These dispersals may have been aided by the West Wind Drift, but rafting across the Mozambique Channel is also possible, and could be aided by the existence of developmental stages that require minimal or no feeding and by tolerance to sea water and spume. Accumulating evidence suggests that many biogeographical patterns in the southern hemisphere may be better explained by dispersal than by Gondwanan vicariance hypotheses. Our results add to this growing body of data and raise the possibility that some puzzling trans‐Indian Ocean distributions may also be explained by historical dispersal events across oceanic barriers that now seem insuperable.  相似文献   
6.
We present an approach for providing quantitative insight into the production‐ecological sustainability of biofuel feedstock production systems. The approach is based on a simple crop‐soil model and was used for assessing feedstock from current and improved production systems of cassava for bioethanol. Assessments were performed for a study area in Mozambique, a country considered promising for biomass production. Our focus is on the potential role of smallholders in the production of feedstock for biofuels. We take cassava as the crop for this purpose and compare it with feedstock production on plantations using sugarcane, sweet sorghum and cassava as benchmarks. Production‐ecological sustainability was defined by seven indicators related to resource‐use efficiency, soil quality, net energy production and greenhouse gas (GHG) emissions. Results indicate that of the assessed systems, sugarcane performed better than cassava, although it requires substantial water for irrigation. Targeted use of nutrient inputs improved sustainability of smallholder cassava. Cassava production systems on more fertile soils were more sustainable than those on less fertile soils; the latter required more external inputs for achieving the same output, affecting most indicators negatively and reducing the feasibility for smallholders. Cassava and sweet sorghum performed similarly. Cassava production requires much more labour per hectare than production of sugarcane or sweet sorghum. Production of bioethanol feedstock on cultivated lands was more sustainable and had potential for carbon sequestration, avoiding GHG emissions from clearing natural vegetation if new land is opened.  相似文献   
7.
Sponges assemblages were sampled in four coastal study regions (Malindi, Kenya; Quirimba Archipelago, northern Mozambique; Inhaca Island, Southern Mozambique and Anakao, Madagascar) in the west Indian Ocean. Sponge species were counted in multiple 0.5 m2 quadrats at depths of between 0 and 20 m at a number of sites within localities within each region. Despite the relatively small areas sampled, sponge samples comprised a total of 130 species and 70 genera of the classes Demospongiae and Calcarea. Sponges are clearly a major taxon in these regions in terms of numbers of species, percentage cover or biomass, although their ecology in the west Indian Ocean is virtually unknown. Nearly half of the genera, e.g. Iotrochota, found were species with a so‐called Tethyan distribution. Most of the other genera were cosmopolitan, e.g. Clathria, but some were cold water (Coelosphaera), Indo‐Australian (Ianthella) or circum‐African (Crambe). Many of the species encountered in the present study occurred in at least two study regions, many in more and could occupy large areas of substratum. Some of these, e.g. Xestospongia exigua, are commonly found throughout the Indo‐west Pacific region where they also occupy much space. The endemicity of the shallow water sponge faunas in East Africa (20–25%) seem to be high within the Indo‐Pacific realm but are lower than northern Papua New Guinea. The tropical regions (Kenya and Northern Mozambique) were more speciose than subtropical regions (southern Mozambique and Madagascar) but not significantly more diverse (Shannon H′). Although latitude was not a major influence on sponge community patterns, hard substratum assemblages did form a cline from the tropics to Southern Mozambique, linked by Madagascar. Substratum nature (habitat) was most important in influencing the suite and number of species present. Sponge assemblages of soft substrata were much more dissimilar, both within and between habitats, than those on hard substrata. There was a predictable variability in species richness between hard substratum habitats: coral reefs being speciose and caves being less so. Our findings showed that both patterns and influences on species richness may be decoupled from those influencing diversity. In our data species richness, but not diversity, showed striking regional and bathymetric trends. In addition, sponge species richness mainly split at coral reef vs. non‐reef habitats, whilst diversity divided principally into assemblages on hard and soft substrata. We consider this dichotomy of findings between species richness and diversity values to be important, as these are two principal measures used for the interpretation of biodiversity.  相似文献   
8.
The recent expansion of Pentecostalism and independent churches in Africa has generated growing interest among social scientists. This attention parallels a renewed interest among Africanists on witchcraft and occult activities, also believed by many to be increasing. Some suggest the two trends may be related, but it remains unclear how and why. Drawing on a study of Pentecostalism and health in the city of Chimoio, Mozambique, in 2002–03 that focused on attitudes toward recent social change, we argue that structural adjustment economic reforms have deepened economic inequality and exacerbated household stresses that affect men and women differently. Women increasingly seek spiritual help for reproductive health problems from Pentecostal churches, whereas men disproportionately pay traditional healers to engage "occult" practices to manage misfortune related to employment. The increased resort to both spiritual resources reveals social distress caused by economic adjustment, with important implications for health programs.  相似文献   
9.
Crustacea Decapoda and Stomatopoda are inventoried for the first time in Juan de Nova Island, Iles Eparses, Mozambique channel. In total, 112 species are reported: 69 crabs, 28 anomurans, 11 shrimps, 3 mantis shrimps and 1 lobster. A comparison is made with nearby islands in the Mozambique channel: Glorieuses Islands (157 species), Europa Island (178 species), and Mayotte Island (505 species). The lower species richness at Juan de Nova is explained by the small size of the island and by the difficulties to collect the crustaceans on the reef flat hardly accessible at low tide. The crustaceans are listed by main habitats from land to outer reef (2–20 m). The presence of the coconut crab (Birgus latro), an endangered species vulnerable to human predation, is confirmed.  相似文献   
10.
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