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A major obstacle to selecting the most appropriate crops and closing the yield gap in many areas of the world is a lack of site-specific soil information. Accurate information on soil properties is critical for identifying soil limitations and the management practices needed to improve crop yields. However, acquiring accurate soil information is often difficult due to the high spatial and temporal variability of soil properties at fine scales and the cost and inaccessibility of laboratory-based soil analyses. With recent advancements in predictive soil mapping, there is a growing expectation that soil map predictions can provide much of the information needed to inform soil management. Yet, it is unclear how accurate current soil map predictions are at scales relevant to management. The main objective of this study was to address this issue by evaluating the site-specific accuracy of regional-to-global soil maps, using Ghana as a test case. Four web-based soil maps of Ghana were evaluated using a dataset of 6514 soil profile descriptions collected on smallholder farms using the LandPKS mobile application. Results from this study revealed that publicly available soil maps in Ghana lack the needed accuracy (i.e., correct identification of soil limitations) to reliably inform soil management decisions at the 1–2 ha scale common to smallholders. Standard measures of map accuracy for soil texture class and rock fragment class predictions showed that all soil maps had similar performance in estimating the correct property class. Overall soil texture class accuracies ranged from 8 %–14 % but could be as high as 38 %–64 % after accounting for uncertainty in the evaluation dataset. Soil rock fragment class accuracies ranged from 26 %–29 %. However, despite these similar overall accuracies, there were substantial differences in soil property predictions among the four maps, highlighting that soil map errors are not uniform between maps. To better understand the functional implications of these soil property differences, we used a modified version of the FAO Global Agro-Ecological Zone (GAEZ) soil suitability modeling framework to derive soil suitability ratings for each soil data source. Using a low-input, rain-fed, maize production scenario, we evaluated the functional accuracy of map-based soil property estimates. This analysis showed that soil map data significantly overestimated crop suitability for over 65 % of study sites, potentially leading to ineffective agronomic investments by farmers, including cash-constrained smallholders.

A major obstacle to selecting the most appropriate crops and closing the yield gap in many areas of the world is a lack of site-specific soil information. Accurate information on soil properties is critical for identifying soil limitations and the management practices needed to improve crop yields. However, acquiring accurate soil information is often difficult due to the high spatial and temporal variability of soil properties at fine scales and the cost and inaccessibility of laboratory-based soil analyses. With recent advancements in predictive soil mapping, there is a growing expectation that soil map predictions can provide much of the information needed to inform soil management. Yet, it is unclear how accurate current soil map predictions are at scales relevant to management. The main objective of this study was to address this issue by evaluating the site-specific accuracy of regional-to-global soil maps, using Ghana as a test case. Four web-based soil maps of Ghana were evaluated using a dataset of 6,514 soil profile descriptions collected on smallholder farms using the LandPKS mobile application. Results from this study revealed that publicly available soil maps in Ghana lack the needed accuracy (i.e., correct identification of soil limitations) to reliably inform soil management decisions at the 1–2 ha scale common to smallholders. Standard measures of map accuracy for soil texture class and rock fragment class showed that all soil maps had similar performance in estimating the correct property class, with overall accuracies ranging from 8–39 % for soil texture classes and 26–33 % for soil rock fragment classes. Furthermore, there were substantial differences in soil property predictions among the four maps, highlighting that soil map errors are not uniform between maps despite their similar overall accuracies. To better understand the functional implications of these soil property differences, we used a modified version of the FAO Global Agro-Ecological Zone (GAEZ) soil suitability modelling framework to derive soil suitability ratings for each soil data source. Using a low-input, rain-fed, maize production scenario, we evaluated the functional accuracy of map-based soil property estimates. This analysis showed that soil map data significantly overestimated crop suitability for over 65 % of study sites, potentially leading to ineffective agronomic investments by farmers, including cash-constrained smallholders.

In theory, performance rewards motivate agents to undertake activities intended to generate desired policy outcomes, especially in an authoritarian regime. This study examines implementation activi...

In the Americas, some mosquito-borne viruses such as Zika, chikungunya, and dengue circulate among humans in urban transmission cycles, while others, including yellow fever and Mayaro, circulate among monkeys in sylvatic cycles. The intersection of humans and wildlife at forest edges creates risk for zoonotic virus exchange. We built a scaffold tower at the edge of a treefall gap in rainforest bordering Manaus, Brazil, to identify vectors that may bridge transmission between humans and monkeys. We vertically sampled diurnally active, anthropophilic mosquitoes using handheld nets at 0, 5, and 9 m and container-breeding mosquitoes in ovitraps at 0, 5, 10, and 15 m. Haemagogus janthinomys and Psorophora amazonica were present in high relative abundance in nets at each height sampled, while anthropophilic species were uncommon in ovitraps. Hg. janthinomys was more abundant at elevated heights than at ground level, while Ps. amazonica abundance was not significantly stratified across heights. The presence of each species increased with increasing 7-day rainfall lagged at 1 week, and at 1 and 4 weeks prior to collection, respectively. In addition, Hg. janthinomys was most frequently collected at 29.9 °C, irrespective of height. These data provide insight into the potential role of each species as bridge vectors.

Deforestation precipitates spillover of enzootic, vector‐borne viruses into humans, but specific mechanisms for this effect have rarely been investigated. Expansion of oil palm cultivation is a major driver of deforestation. Here, we demonstrate that mosquito abundance decreased over ten stepwise distances from interior forest into conterminous palm plantations in Borneo. Diversity in interior plantation narrowed to one species, Aedes albopictus, a potential bridge vector for spillover of multiple viruses. A. albopictus was equally abundant across all distances in forests, forest‐plantation edge, and plantations, while A. niveus, a known vector of sylvatic dengue virus, was found only in forests. A. albopictus collections were significantly female‐biased in plantation but not in edge or forest. Our data reveal that the likelihood of encountering any mosquito is greater in interior forest and edge than plantation, while the likelihood of encountering A. albopictus is equivalent across the gradient sampled from interior plantation to interior forest.

The emergence of Zika virus (ZIKV) in Latin America brought to the fore longstanding concerns that forests bordering urban areas may provide a gateway for arbovirus spillback from humans to wildlife. To bridge urban and sylvatic transmission cycles, mosquitoes must co-occur with both humans and potential wildlife hosts, such as monkeys, in space and time. We deployed BG-Sentinel traps at heights of 0, 5, 10, and 15 m in trees in a rainforest reserve bordering Manaus, Brazil, to characterize the vertical stratification of mosquitoes and their associations with microclimate and to identify potential bridge vectors. Haemagogus janthinomys and Sabethes chloropterus, two known flavivirus vectors, showed significant stratification, occurring most frequently above the ground. Psorophora amazonica, a poorly studied anthropophilic species of unknown vector status, showed no stratification and was the most abundant species at all heights sampled. High temperatures and low humidity are common features of forest edges and microclimate analyses revealed negative associations between minimum relative humidity, which was inversely correlated with maximum temperature, and the occurrence of Haemagogus and Sabethes mosquitoes. In this reserve, human habitations border the forest while tamarin and capuchin monkeys are also common to edge habitats, creating opportunities for the spillback of mosquito-borne viruses.

Land cover and land use change (LCLUC) acts as a catalyst for spillover of arthropod-borne pathogens into novel hosts by shifting host and vector diversity, abundance, and distribution, ultimately reshaping host–vector interactions. Identification of bloodmeals from wild-caught mosquitoes provides insight into host utilization of particular species in particular land cover types, and hence their potential role in pathogen maintenance and spillover. Here, we collected 134 blood-engorged mosquitoes comprising 10 taxa across 9 land cover types in Sarawak, Malaysian Borneo, a region experiencing intense LCLUC and concomitant spillover of arthropod-borne pathogens. Host sources of blood were successfully identified for 116 (87%) mosquitoes using cytochrome oxidase subunit I (COI) barcoding. A diverse range of hosts were identified, including reptiles, amphibians, birds, and mammals. Sixteen engorged Aedes albopictus, a major vector of dengue virus, were collected from seven land cover types and found to feed exclusively on humans (73%) and boar (27%). Culex tritaeniohynchus (n = 2), Cx. gelidus (n = 3), and Cx. quiquefasciatus (n = 3), vectors of Japanese encephalitis virus, fed on humans and pigs in the rural built-up land cover, creating potential transmission networks between these species. Our data support the use of COI barcoding to characterize mosquito–host networks in a biodiversity hotspot.

Remotely sensed imagery at multiple spatial scales is used increasingly in conjunction with field data to estimate rangeland indicators (e.g., vegetation cover) and meet the growing need for landscape-scale monitoring and assessment of rangelands. Remote sensing studies that produce rangeland indicators often require intensive and costly field-data collection efforts to produce accurate model predictions. Existing monitoring data, such as those collected by the Bureau of Land Management’s Assessment, Inventory, and Monitoring (AIM) program, are potentially useful sources of field data in remote sensing modeling studies. Given their data-hungry nature, common regression tree − based modeling approaches may be inadequate for reliably predicting rangeland indicators with the smaller sample sizes of AIM data than typically used for remote sensing studies. Current literature suggests that Bayesian models, such as Bayesian additive regression trees (BART), may provide a suitable alternative to traditional regression tree − based modeling approaches to overcome the sample size limitation of the AIM data. In this study, we used 182 AIM field plots together with both high (RapidEye) and moderate (Landsat OLI) spatial resolution satellite imagery to predict bare ground and bare soil, total foliar, herbaceous, woody, and shrub cover indicators on rangelands in a 14 625-km2 area of northeastern California. We demonstrate that a BART model performed similarly to other regression tree approaches when field data and high spatial resolution imagery predictions were combined to predict indicator values using the medium spatial resolution Landsat image. The BART models also provided spatially explicit uncertainty estimates, which allow land managers to more carefully evaluate indicator predictions and to identify areas where future field data collection might be most useful. This study demonstrates that existing field data and freely available, remotely sensed imagery can be integrated to produce spatially explicit and continuous surface estimates of rangeland indicators across entire landscapes.

On the Ground • Opportunities for rangeland inventory and monitoring have been transformed by innovations in both indicator and methods standardization and new technologies. • These technologies make it easier to collect, store, access, and interpret inventory and monitoring data. • The Land-Potential Knowledge System (LandPKS) platform and apps help users with little or no soils knowledge to describe their soil, and for those with little botanical knowledge to monitor key shifts in the relative dominance of plant structural groups. • The system also allows users to easily share and compare their data with others.

BackgroundAedes aegypti mosquitoes are vectors of a variety of emerging viral pathogens, including yellow fever, dengue, chikungunya, and Zika virus. This species has established endemic populations in all cities across southern New Mexico sampled to date. Presently, control of Aedes-borne viruses relies on deployment of insecticides to suppress mosquito populations, but the evolution of insecticide resistance threatens the success of vector control programs. While insecticide resistance is quite common in Ae. aegypti field populations across much of the U.S., the resistance status of this species in populations from New Mexico has not previously been assessed.ResultsFirst, we collected information on pesticide use in cities in southern New Mexico and found that the most commonly used active ingredients were pyrethroids. The use of insecticides with the same mode-of-action over multiple years is likely to promote the evolution of resistance. To determine if there was evidence of resistance in some cities in southern New Mexico, we collected Ae. aegypti from the same cities and established laboratory strains to assess resistance to pyrethroid insecticides and, for a subset of populations, to organophosphate insecticides. F2 or F4 generation mosquitoes were assessed for insecticide resistance using bottle test bioassays. The majority of the populations from New Mexico that we analyzed were resistant to the pyrethroids permethrin and deltamethrin. A notable exception to this trend were mosquitoes from Alamogordo, a city that did not report using pyrethroid insecticides for vector control. We screened individuals from each population for known knock down resistance (kdr) mutations via PCR and found a strong association between the presences of the F1534C kdr mutation in the para gene of Ae. aegypti (homologue to F1534C in Musca domestica L.) and pyrethroid resistance.ConclusionHigh-level pyrethroid resistance is common in Ae. aegypti from New Mexico and geographic variation in such resistance is likely associated with variation in usage of pyrethroids for vector control. Resistance monitoring and management is recommended in light of the potential for arbovirus outbreaks in this state. Also, alternative approaches to mosquito control that do not involve insecticides should be explored.

The composition, density, diversity, and temporal distribution of mosquito species and the influence of temperature, relative humidity, and rainfall on these data were investigated in 50 sites across five land cover classes (forest, savannah, barren, village, and agriculture) in southeastern Senegal. Mosquitoes were collected monthly in each site between June 2009 and March 2011, with three people collecting mosquitoes landing on their legs for one to four consecutive days. In total, 81,219 specimens, belonging to 60 species and 7 genera, were collected. The most abundant species were Aedes furcifer (Edwards) (Diptera: Culicidae) (20.7%), Ae. vittatus (Bigot) (19.5%), Ae. dalzieli (Theobald) (14.7%), and Ae. luteocephalus (Newstead) (13.7%). Ae. dalzieli, Ae. furcifer, Ae. vittatus, Ae. luteocephalus, Ae. taylori Edwards, Ae. africanus (Theobald), Ae. minutus (Theobald), Anopheles coustani Laveran, Culex quinquefasciatus Say, and Mansonia uniformis (Theobald) comprised ≥10% of the total collection, in at least one land cover. The lowest species richness and Brillouin diversity index (HB = 1.55) were observed in the forest-canopy. The urban-indoor fauna showed the highest dissimilarity with other land covers and was most similar to the urban-outdoor fauna following Jaccard and Morisita index. Mosquito abundance peaked in June and October 2009 and July and October 2010. The highest species density was recorded in October. The maximum temperature was correlated positively with mean temperature and negatively with rainfall and relative humidity. Rainfall showed a positive correlation with mosquito abundance and species density. These data will be useful for understanding the transmission of arboviruses and human malaria in the region.

Mosquito-borne Zika virus (ZIKV) was recently introduced into the Americas and now has the potential to spill back into a sylvatic cycle in the region, likely involving non-human primates and Aedes, Haemagogus, and Sabethes species mosquitoes. We investigated potential routes of mosquito-borne virus exchange between urban and sylvatic transmission cycles by characterizing mosquito communities in three urban forest parks that receive heavy traffic from both humans and monkeys in Manaus, Brazil. Parks were stratified by both distance from the urban-forest edge (0, 50, 100, and 500 m) and relative Normalized Difference Vegetation Index (NDVI) (low, medium, or high), and mosquitoes were sampled at randomly selected sites within each stratum using BG-Sentinel traps. Additionally, temperature, relative humidity, and other environmental data were collected at each site. A total of 1,172 mosquitoes were collected from 184 sites sampled in 2018, of which 98 sites were resampled in 2019. Using park as the unit of replication (i.e. 3 replicates per sampling stratum), a two-way ANOVA showed no effect of distance or NDVI on the mean number of identified species (P > 0.05 for both comparisons) or on species diversity as measured by the Shannon-Wiener diversity index (P > 0.10 for both comparisons). However, the Morisita overlap index revealed that mosquito communities changed substantially with increasing distance from edge, with communities at 0 m and 500 m being quite distinct. Aedes albopictus and Ae. aegypti penetrated at least 100 m into the forest, while forest specialists including Haemagogus janthinomys, Sabethes glaucodaemon, and Sa. tridentatus were detected in low numbers within 100 m from the forest edge. Trichoprosopon digitatum and Psorophora amazonica were among the most abundant species collected, and both showed distributions extending from the forest edge to its interior. Our results show overlapping distributions of urban and forest mosquitoes at park edges, which highlights the risk of arbovirus exchange via multiple bridge vectors in Brazilian urban forest parks. These parks may also provide refugia for both Ae. albopictus and Ae. aegypti from mosquito control programs.

The mosquitoesAedes aegypti(L.) andAe. albopictusSkuse are the major vectors of dengue, Zika, yellow fever and chikungunya viruses worldwide.Wolbachia, an endosymbiotic bacterium present in many insects, is being utilized in novel vector control strategies to manipulate mosquito life history and vector competence to curb virus transmission. Earlier studies have found thatWolbachiais commonly detected inAe.albopictusbut rarely detected inAe. aegypti. In this study, we used a two-step PCR assay to detectWolbachiain wild-collected samples ofAe. aegypti.The PCR products were sequenced to validate amplicons and identifyWolbachiastrains. A loop-mediated isothermal amplification (LAMP) assay was developed and used for detectingWolbachiain selected mosquito specimens as well. We foundWolbachiain 85/148 (57.4%) wildAe. aegyptispecimens from various cities in New Mexico and in 2/46 (4.3%) from St. Augustine, Florida. We did not detectWolbachiain 94 samples ofAe. aegyptifrom Deer Park, Harris County, Texas.Wolbachiadetected inAe. aegyptifrom both New Mexico and Florida was thewAlbB strain ofWolbachia pipientis.AWolbachiapositive colony ofAe. aegyptiwas established from pupae collected in Las Cruces, New Mexico in 2018. The infected females of this strain transmittedWolbachiato their progeny when crossed with males of Rockefeller strain ofAe. aegypti, which does not carryWolbachia.In contrast, none of the progeny of progeny of Las Cruces males mated to Rockefeller females were infected withWolbachia.

Background Chikungunya virus (CHIKV) originated in a sylvatic cycle of transmission between non-human animal hosts and vector mosquitoes in the forests of Africa. Subsequently the virus jumped out of this ancestral cycle into a human-endemic transmission cycle vectored by anthropophilic mosquitoes. Sylvatic CHIKV cycles persist in Africa and continue to spill over into humans, creating the potential for new CHIKV strains to enter human-endemic transmission. To mitigate such spillover, it is first necessary to delineate the distributions of the sylvatic mosquito vectors of CHIKV, to identify the environmental factors that shape these distributions, and to determine the association of mosquito presence with key drivers of virus spillover, including mosquito and CHIKV abundance. We therefore modeled the distribution of seven CHIKV mosquito vectors over two sequential rainy seasons in Kédougou, Senegal using Maxent. Methods Mosquito data were collected in fifty sites distributed in five land cover classes across the study area. Environmental data representing land cover, topographic, and climatic factors were included in the models. Models were compared and evaluated using area under the receiver operating characteristic curve (AUROC) statistics. The correlation of model outputs with abundance of individual mosquito species as well as CHIKV-positive mosquito pools was tested. Results Fourteen models were produced and evaluated; the environmental variables most strongly associated with mosquito distributions were distance to large patches of forest, landscape patch size, rainfall, and the normalized difference vegetation index (NDVI). Seven models were positively correlated with mosquito abundance and one (Aedes taylori) was consistently, positively correlated with CHIKV-positive mosquito pools. Eight models predicted high relative occurrence rates of mosquitoes near the villages of Tenkoto and Ngary, the areas with the highest frequency of CHIKV-positive mosquito pools. Conclusions Of the environmental factors considered here, landscape fragmentation and configuration had the strongest influence on mosquito distributions. Of the mosquito species modeled, the distribution of Ae. taylori correlated most strongly with abundance of CHIKV, suggesting that presence of this species will be a useful predictor of sylvatic CHIKV presence. Electronic supplementary material The online version of this article (10.1186/s13071-018-2832-6) contains supplementary material, which is available to authorized users.

During the wet season of 2010, yellow fever virus (YFV) was detected in field-collected mosquitoes in the Kédougou region in southeastern Senegal. During this outbreak, we studied the association of the abundance of YFV-infected mosquitoes and land cover features to try and understand the dynamics of YFV transmission within the region. In total, 41,234 mosquito females were collected and tested for virus infection in 5,152 pools. YFV was detected in 67 pools; species including Aedes furcifer (52.2% of the infected pools), Ae. luteocephalus (31.3% of the infected pools), Ae. taylori (6.0% of the infected pools) and six other species (10.4% of the infected pools) captured in September (13.4%), October (70.1%), and November (16.4%). Spatially, YFV was detected from mosquitoes collected in all land cover classes but mainly, forest canopies (49.2%). Human infection is likely mediated by Ae. furcifer, the only species found infected with YFV within villages. Villages containing YFV-infected mosquitoes were significantly closer to large forests (> 2 ha) than villages in which no infected mosquitoes were detected.

Woody vegetation has expanded in coverage over the past century in many places globally, exemplified by pinyon-juniper changes in the Southwestern United States. Extreme drought is one of the few non-management drivers besides fire that might reverse such cover changes, but this has not been well documented. Here, we assess 68 years of tree cover dynamics across an elevation gradient of a pinyon-juniper woodland using aerial photographs (1936 and 1959) and QuickBird imagery (2004). Canopy cover increased 32% from 1936 to the onset of a major drought (2002). The largest relative increase in canopy cover occurred from 1936 to 1959 at the higher elevations, but these gains were eliminated by fires occurring from 1959 to 2002, during which time lower elevations with low canopy cover exhibited the greatest relative increases. The 2002–2004 drought reduced canopy cover by 55%, which eliminated gains in cover that occurred since 1936. Relative tree cover loss was highest at low elevations with low tree cover, but absolute tree cover loss was greater in areas of high tree cover, which increased with elevation. The loss of more than half of the canopy cover during a 2-year drought period was much greater than losses due to fire or possible increases due to historic land use (for example, grazing). These results suggest that regional-scale climatic influences may be more important than land use legacies in controlling tree cover of these and perhaps other semiarid woodlands over longer time scales—notable given that similar episodes of tree mortality are projected in coming decades with climate change.

For land degradation monitoring and assessment (M&A) to be accurate and for sustainable land management (SLM) to be effective, it is necessary to incorporate multiple knowledges using a variety of methods and scales, and this must include the (potentially conflicting) perspectives of those who use the land. This paper presents a hybrid methodological framework that builds on approaches developed by UN Food & Agriculture Organisation's land degradation Assessment in Drylands (LADA), the World Conservation Approaches and Technologies (WOCAT) programme and the Dryland Development Paradigm (DDP), and is being applied internationally through the EU-funded DESIRE project. The framework suggests that M&A should determine the progress of SLM towards meeting sustainability goals, with results continually and iteratively enhancing SLM decisions. The framework is divided into four generic themes: (i) establishing land degradation and SLM context and sustainability goals; (ii) identifying, evaluating and selecting SLM strategies; (iii) selecting land degradation and SLM indicators and (iv) applying SLM options and monitoring land degradation and progress towards sustainability goals. This approach incorporates multiple knowledge sources and types (including land manager perspectives) from local to national and international scales. In doing so, it aims to provide outputs for policy-makers and land managers that have the potential to enhance the sustainability of land management in drylands, from the field scale to the region, and to national and international levels. The paper draws on operational experience from across the DESIRE project to break the four themes into a series of methodological steps, and provides examples of the range of tools and methods that can be used to operationalise each of these steps. Refereed/Peer-reviewed

Sustainable dryland management seeks to improve the conditions of people and ecosystems affected by degradation, but it is often unclear which land management strategies work, which ones do not and why. Monitoring and assessment (M&A) can support decision-making by providing this information. As implied by the 10-year Strategy of the United Nations Convention to Combat Desertification (UNCCD), however, M&A efforts have thus far been insufficient or inadequate. We argue that integrative geospatial approaches should be implemented to enhance dryland management decision-making. By assimilating and linking human and environmental data, qualitative and quantitative data, as well as field and remotely sensed data in a spatially explicit framework, such approaches facilitate assessments of both the complexities and place-specificities inherent to sustainability. In addition, they help represent different stakeholder perspectives, promote communication among scientists from diverse backgrounds as well as between scientific and local experts, facilitate inter-institutional knowledge sharing, and create synergy between the UNCCD and other Conventions. Due to these benefits as well as the rapid evolution and increasing availability and affordability of geospatial data and technologies in all countries, it is appropriate to begin capitalizing more fully on them now for the M&A of land management sustainability. In order for integrative geospatial approaches to become more central to M&A efforts, however, capacities and infrastructure must be improved and standards and protocols developed for the collection, analysis, and modeling of data, for the evaluation of outputs, and for the reporting of results. Copyright © 2010 John Wiley & Sons, Ltd.

The risk of human infection with sylvatic chikungunya (CHIKV) virus was assessed in a focus of sylvatic arbovirus circulation in Senegal by investigating distribution and abundance of anthropophilic Aedes mosquitoes, as well as the abundance and distribution of CHIKV in these mosquitoes. A 1650 km2 area was classified into five land cover classes: forest, barren, savanna, agriculture and village. A total of 39,799 mosquitoes was sampled from all classes using human landing collections between June 2009 and January 2010. Mosquito diversity was extremely high, and overall vector abundance peaked at the start of the rainy season. CHIKV was detected in 42 mosquito pools. Our data suggest that Aedes furcifer, which occurred abundantly in all land cover classes and landed frequently on humans in villages outside of houses, is probably the major bridge vector responsible for the spillover of sylvatic CHIKV to humans., Author Summary Chikungunya is a mosquito-borne virus that infects and sickens people in many tropical, urban regions of the world. This virus circulates in forest cycles of West Africa, where mosquitoes transmit it among non-human primates. It also infects humans via bridge vectors, mosquitoes that feed on both non-human primates and humans. To date, little is known about the environmental factors that influence the abundance and distribution of mosquito vectors that participate in the forest cycle of this virus or about specific mosquitoes that are likely to act as bridge vectors. We studied the distribution and abundance of mosquitoes potentially involved in the forest cycle in southeastern Senegal, as well as their infection by this virus. Satellite imagery was used to classify the region into the 5 most abundant land cover elements, and mosquitoes attracted to humans were collected in sites representing each land cover class. We found that Aedes furcifer, a mosquito that occurs in all land cover types and also enters villages to feed on humans, is probably the most important bridge vector between forest circulation and human populations.

We take a fresh look at geography curricula and their appropriateness to the demands of the 21st century. We reflect on the purpose, content and relevance of undergraduate geography curricula in an age of 'supercomplexity'. Geography curricula, by their nature, are varied and multiple, with different countries often privileging different types of geographical knowledge and skills. The paper emerges from a group of US and UK geographers and so focuses mainly upon Anglo-American geographical traditions. We highlight the need to provide generic and employability skills as part of the rapidly changing requirements into which geographical skills and knowledge need to be integrated. The knowledge base may well change according to circumstances (for example, adaptation to environmental change) that will require geographers to be able to contribute to the community and thereby enhance the overall stature of geography. A geographical outlook, reflecting space and change, remains at the heart of geography and can provide a unique selling point for its study. Graduates will need to promote their geographical knowledge and skills in order to cope with employment possibilities, so instructors will need to diversify their teaching methods to embrace active learning and problem-orientated approaches to the delivery of geographical curricula. Refereed/Peer-reviewed

Background Zika virus (ZIKV; genus Flavivirus, family Flaviviridae) is maintained in a zoonotic cycle between arboreal Aedes spp. mosquitoes and nonhuman primates in African and Asian forests. Spillover into humans has been documented in both regions and the virus is currently responsible for a large outbreak in French Polynesia. ZIKV amplifications are frequent in southeastern Senegal but little is known about their seasonal and spatial dynamics. The aim of this paper is to describe the spatio-temporal patterns of the 2011 ZIKV amplification in southeastern Senegal. Methodology/Findings Mosquitoes were collected monthly from April to December 2011 except during July. Each evening from 18∶00 to 21∶00 hrs landing collections were performed by teams of 3 persons working simultaneously in forest (canopy and ground), savannah, agriculture, village (indoor and outdoor) and barren land cover sites. Mosquitoes were tested for virus infection by virus isolation and RT-PCR. ZIKV was detected in 31 of the 1,700 mosquito pools (11,247 mosquitoes) tested: Ae. furcifer (5), Ae. luteocephalus (5), Ae. africanus (5), Ae. vittatus (3), Ae. taylori, Ae. dalzieli, Ae. hirsutus and Ae. metallicus (2 each) and Ae. aegypti, Ae. unilinaetus, Ma. uniformis, Cx. perfuscus and An. coustani (1 pool each) collected in June (3), September (10), October (11), November (6) and December (1). ZIKV was detected from mosquitoes collected in all land cover classes except indoor locations within villages. The virus was detected in only one of the ten villages investigated. Conclusions/Significance This ZIKV amplification was widespread in the Kedougou area, involved several mosquito species as probable vectors, and encompassed all investigated land cover classes except indoor locations within villages. Aedes furcifer males and Aedes vittatus were found infected within a village, thus these species are probably involved in the transmission of Zika virus to humans in this environment.