WorldWideScience

Sample records for congo basin forests

  1. Forest Elephant Crisis in the Congo Basin

    Science.gov (United States)

    Blake, Stephen; Strindberg, Samantha; Boudjan, Patrick; Makombo, Calixte; Bila-Isia, Inogwabini; Ilambu, Omari; Grossmann, Falk; Bene-Bene, Lambert; de Semboli, Bruno; Mbenzo, Valentin; S'hwa, Dino; Bayogo, Rosine; Williamson, Liz; Fay, Mike; Hart, John; Maisels, Fiona

    2007-01-01

    Debate over repealing the ivory trade ban dominates conferences of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Resolving this controversy requires accurate estimates of elephant population trends and rates of illegal killing. Most African savannah elephant populations are well known; however, the status of forest elephants, perhaps a distinct species, in the vast Congo Basin is unclear. We assessed population status and incidence of poaching from line-transect and reconnaissance surveys conducted on foot in sites throughout the Congo Basin. Results indicate that the abundance and range of forest elephants are threatened from poaching that is most intense close to roads. The probability of elephant presence increased with distance to roads, whereas that of human signs declined. At all distances from roads, the probability of elephant occurrence was always higher inside, compared to outside, protected areas, whereas that of humans was always lower. Inside protected areas, forest elephant density was correlated with the size of remote forest core, but not with size of protected area. Forest elephants must be prioritised in elephant management planning at the continental scale. PMID:17407383

  2. Monitoring Forest Carbon Stocks and Fluxes in the Congo Basin

    OpenAIRE

    2010-01-01

    The Central African Forests Commission (COMIFAC) and its partners (OFAC, USAID, EC-JRC, OSFAC, WWF, WRI, WCS, GOFC-GOLD, START, UN-FAO) organized an international conference on "Monitoring of Carbon stocks and fluxes in the Congo Basin" in Brazzaville, Republic of Congo, 2-4 February 2010. The conference brought together leading international specialists to discuss approaches for quantifying stocks and flows of carbon in tropical forests of the Congo Basin. The conference provided a unique op...

  3. Profiling climate change vulnerability of forest indigenous communities in the Congo Basin

    NARCIS (Netherlands)

    Nkem, J.N.; Somorin, O.A.; Jum, C.; Idinoba, M.E.; Bele, Y.M.; Sonwa, D.J.

    2013-01-01

    The livelihood strategies of indigenous communities in the Congo Basin are inseparable from the forests, following their use of forest ecosystem goods and services (FEGS). Climate change is expected to exert impacts on the forest and its ability to provide FEGS. Thus, human livelihoods that depend

  4. Governing Congo Basin forests in a changing climate: actors, discourses and institutions for adaptation and mitigation

    NARCIS (Netherlands)

    Somorin, O.A.

    2014-01-01

    Governing Congo Basin Forests in a Changing Climate: Actors, Discourses and Institutions for Adaptation and Mitigation

    OA Somorin

    Abstract

    The thesis deals with the central question of the governance processes of making

  5. Gender implications of forest product value chains in the Congo basin

    NARCIS (Netherlands)

    Ingram, V.; Schure, J.M.; Tieguhong, J.C.; Ndoye, O.; Awono, A.; Iponga, D.M.

    2014-01-01

    Activities and roles in value chains of forest products in the Congo Basin are highly gendered, varying with the product's characteristics, the segment of the chain and customary regulations and norms. High-value products are primarily male-harvested when customary rules govern tenure and access,

  6. The nitrogen budget for different forest types in the central Congo Basin

    Science.gov (United States)

    Bauters, Marijn; Verbeeck, Hans; Cizungu, Landry; Boeckx, Pascal

    2016-04-01

    Characterization of fundamental processes in different forest types is vital to understand the interaction of forests with their changing environment. Recent data analyses, as well as modeling activities have shown that the CO2 uptake by terrestrial ecosystems strongly depends on site fertility, i.e. nutrient availability. Accurate projections of future net forest growth and terrestrial CO2 uptake thus necessitate an improved understanding on nutrient cycles and how these are coupled to the carbon (C) cycle in forests. This holds especially for tropical forests, since they represent about 40-50% of the total carbon that is stored in terrestrial vegetation, with the Amazon basin and the Congo basin being the largest two contiguous blocks. However, due to political instability and reduced accessibility in the central Africa region, there is a strong bias in scientific research towards the Amazon basin. Consequently, central African forests are poorly characterized and their role in global change interactions shows distinct knowledge gaps, which is important bottleneck for all efforts to further optimize Earth system models explicitly including this region. Research in the Congo Basin region should combine assessments of both carbon stocks and the underlying nutrient cycles which directly impact the forest productivity. We set up a monitoring network for carbon stocks and nitrogen fluxes in four different forest types in the Congo Basin, which is now operative. With the preliminary data, we can get a glimpse of the differences in nitrogen budget and biogeochemistry of African mixed lowland rainforest, monodominant lowland forest, mixed montane forest and eucalypt plantations.

  7. Linking plant functional traits and forest carbon stocks in the Congo Basin

    Science.gov (United States)

    Kearsley, Elizabeth; Verbeeck, Hans; Hufkens, Koen; Lewis, Simon; Huygens, Dries; Beeckman, Hans; Steppe, Kathy; Boeckx, Pascal

    2013-04-01

    Accurate estimates of the amount of carbon stored in tropical forests represent crucial baseline data for recent climate change mitigation policies. Such data are needed to quantify possible emissions due to deforestation and forest degradation, and to evaluate the potential of these forests to act as carbon sinks. Currently, only rough estimates of the carbon stocks for Central African tropical forests are available due to a lack of field data, and little is known about the response of these stocks to climate change. We present the first ground-based carbon stock data for the central Congo Basin in Yangambi, D. R. Congo, based on data of 20 inventory plots of 1 ha covering different forest types. We found an average aboveground carbon stock of 163 ± 19 Mg C ha-1 for intact old-growth forest, which is significantly lower than the stocks recorded in the outer regions of the Congo Basin. Commonly studied drivers for variations of carbon stocks include climatic and edaphic factors, but detailed trait-based studies are lacking. We identified a significant difference in height-diameter relations across the Congo Basin as a driver for spatial differences in carbon stocks. The study of a more detailed interaction of the environment and the available tree species pool as drivers for differences in carbon storage could have large implications. The effect of the species pool on carbon storage can be large since species differ in their ability to sequester carbon, and the collective functional characteristics of plant communities could be a major driver of carbon accumulation. The use of a trait-based approach shows high potential for identifying and quantifying carbon stocks as an ecosystem service. We test for associations between functional trait values and carbon storage across multiple regrowth and old-growth forests types in the Yangambi study area, with soil properties and climate similar for all plots. A selection of traits associated with carbon dynamics is made

  8. Win-wins in NTFP market chains? How governance impacts the sustainability of livelihoods based on Congo Basin forest products

    NARCIS (Netherlands)

    Ingram, V.J.

    2012-01-01

    Exploring the interrelationships between governance, poverty alleviation and sustainability impacts in the framework of market chains for non-timber forest products originating from the Congo Basin. The research focuses on how governance arrangements help or hinder access to forest resources and

  9. Foreign capital, forest change and regulatory compliance in Congo Basin forests

    International Nuclear Information System (INIS)

    Brandt, Jodi S; Nolte, Christoph; Agrawal, Arun; Steinberg, Jessica

    2014-01-01

    Tropical forest change is driven by demand in distant markets. Equally, investments in tropical forest landscapes by capital originating from distant emerging economies are on the rise. Understanding how forest outcomes vary by investment source is therefore becoming increasingly important. We empirically evaluate the relationship between investment source and deforestation from 2000 to 2010 in the Republic of Congo. A Congolese forestry code was implemented in 2000 to mitigate degradation of production forests by standardizing all logging in the country according to sustainable forest management (SFM) guidelines. Following the implementation of this law, the majority (73%) of Congo’s production forests were managed by European (40%) and Asian (33%) companies. European concessions had the highest rates of total and core deforestation, followed by Asian concessions, indicating that the fragmentation of intact forests in Congo is strongly associated with industrial logging fueled by foreign capital. European concession holders were also far more likely to comply with SFM policies, followed by Asian concessions, suggesting that compliance with Sustainable Forest Management policies may not mitigate degradation in tropical production forests. Further evaluation of the relationship between investment source, regulatory compliance, and outcomes in tropical countries is essential for effective conservation of tropical forest ecosystems. (paper)

  10. Foreign capital, forest change and regulatory compliance in Congo Basin forests

    Science.gov (United States)

    Brandt, Jodi S.; Nolte, Christoph; Steinberg, Jessica; Agrawal, Arun

    2014-04-01

    Tropical forest change is driven by demand in distant markets. Equally, investments in tropical forest landscapes by capital originating from distant emerging economies are on the rise. Understanding how forest outcomes vary by investment source is therefore becoming increasingly important. We empirically evaluate the relationship between investment source and deforestation from 2000 to 2010 in the Republic of Congo. A Congolese forestry code was implemented in 2000 to mitigate degradation of production forests by standardizing all logging in the country according to sustainable forest management (SFM) guidelines. Following the implementation of this law, the majority (73%) of Congo’s production forests were managed by European (40%) and Asian (33%) companies. European concessions had the highest rates of total and core deforestation, followed by Asian concessions, indicating that the fragmentation of intact forests in Congo is strongly associated with industrial logging fueled by foreign capital. European concession holders were also far more likely to comply with SFM policies, followed by Asian concessions, suggesting that compliance with Sustainable Forest Management policies may not mitigate degradation in tropical production forests. Further evaluation of the relationship between investment source, regulatory compliance, and outcomes in tropical countries is essential for effective conservation of tropical forest ecosystems.

  11. The Potential of Sentinel Satellites for Burnt Area Mapping and Monitoring in the Congo Basin Forests

    Directory of Open Access Journals (Sweden)

    Astrid Verhegghen

    2016-11-01

    Full Text Available In this study, the recently launched Sentinel-2 (S2 optical satellite and the active radar Sentinel-1 (S1 satellite supported by active fire data from the MODIS sensor were used to detect and monitor forest fires in the Congo Basin. In the context of a very strong El Niño event, an unprecedented outbreak of fires was observed during the first months of 2016 in open forests formations in the north of the Republic of Congo. The anomalies of the recent fires and meteorological situation compared to historical data show the severity of the drought. Burnt areas mapped by the S1 SAR and S2 Multi Spectral Instrument (MSI sensors highlight that the fires occurred mainly in Marantaceae forests, characterized by open tree canopy cover and an extensive tall herbaceous layer. The maps show that the origin of the fires correlates with accessibility to the forest, suggesting an anthropogenic origin. The combined use of the two independent and fundamentally different satellite systems of S2 and S1 captured an extent of 36,000 ha of burnt areas, with each sensor compensating for the weakness (cloud perturbations for S2, and sensitivity to ground moisture for S1 of the other.

  12. Shaping forest safety nets with markets: Adaptation to climate change under changing roles of tropical forests in Congo Basin

    International Nuclear Information System (INIS)

    Nkem, Johnson; Kalame, Fobissie B.; Idinoba, Monica; Somorin, Olufunso A.; Ndoye, Ousseynou; Awono, Abdon

    2010-01-01

    Tropical forests hold several goods and services used by forest-dependent people as safety nets to traverse difficult periods of resource supply. These same goods and services are constantly surrounded by emerging markets linking remote communities with major urban centers nationally and internationally. How these markets affect adaptation remains unclear. This paper examines the roles of markets in non-timber forest products that normally serve as safety nets for forest communities, and the implications for climate change adaptation in the Congo Basin. Following the identification and prioritization of forest-based development sectors for adaptation by stakeholders, the types of markets and trades surrounding the identified sectors were examined in two provinces in the Democratic Republic of Congo as a case study in order to evaluate revenue flows and their potential contribution to adaptation by local communities. The distribution of the market revenue leaves local people with returns much lower than the worth of the commodity, while wholesalers and retailers reap most of the benefits and profit from the high variability in volume and market earnings for the same commodity across provinces. Markets may increase the value of a commodity as observed in this study, but their contributions to adaptation appear highly limited for local communities following their distribution among the stakeholders in the market chain. This is likely to be worse in free market settings, especially when it diminishes the safety net roles of forest goods and services. Markets should therefore complement rather than substitute forests roles for adaptation to climate change in tropical forest countries. Capturing the benefits of trade for adaptation is crucial but will require policy reforms and further research that addresses the complexity in benefit sharing.

  13. Differences between Pygmy and Non-Pygmy Hunting in Congo Basin Forests.

    Directory of Open Access Journals (Sweden)

    John E Fa

    Full Text Available We use data on game harvest from 60 Pygmy and non-Pygmy settlements in the Congo Basin forests to examine whether hunting patterns and prey profiles differ between the two hunter groups. For each group, we calculate hunted animal numbers and biomass available per inhabitant, P, per year (harvest rates and killed per hunter, H, per year (extraction rates. We assess the impact of hunting of both hunter groups from estimates of numbers and biomass of prey species killed per square kilometre, and by examining the proportion of hunted taxa of low, medium and high population growth rates as a measure of their vulnerability to overhunting. We then map harvested biomass (kg-1P-1Yr-1 of bushmeat by Pygmies and non-Pygmies throughout the Congo Basin. Hunting patterns differ between Pygmies and non-Pygmies; Pygmies take larger and different prey and non-Pygmies sell more for profit. We show that non-Pygmies have a potentially more severe impact on prey populations than Pygmies. This is because non-Pygmies hunt a wider range of species, and twice as many animals are taken per square kilometre. Moreover, in non-Pygmy settlements there was a larger proportion of game taken of low population growth rate. Our harvest map shows that the non-Pygmy population may be responsible for 27 times more animals harvested than the Pygmy population. Such differences indicate that the intense competition that may arise from the more widespread commercial hunting by non-Pygmies is a far more important constraint and source of conflict than are protected areas.

  14. Effects of logging on roadless space in intact forest landscapes of the Congo Basin.

    Science.gov (United States)

    Kleinschroth, Fritz; Healey, John R; Gourlet-Fleury, Sylvie; Mortier, Frédéric; Stoica, Radu S

    2017-04-01

    Forest degradation in the tropics is often associated with roads built for selective logging. The protection of intact forest landscapes (IFL) that are not accessible by roads is high on the biodiversity conservation agenda and a challenge for logging concessions certified by the Forest Stewardship Council (FSC). A frequently advocated conservation objective is to maximize the retention of roadless space, a concept that is based on distance to the nearest road from any point. We developed a novel use of the empty-space function - a general statistical tool based on stochastic geometry and random sets theory - to calculate roadless space in a part of the Congo Basin where road networks have been expanding rapidly. We compared the temporal development of roadless space in certified and uncertified logging concessions inside and outside areas declared IFL in 2000. Inside IFLs, road-network expansion led to a decrease in roadless space by more than half from 1999 to 2007. After 2007, loss leveled out in most areas to close to 0 due to an equilibrium between newly built roads and abandoned roads that became revegetated. However, concessions in IFL certified by FSC since around 2007 continuously lost roadless space and reached a level comparable to all other concessions. Only national parks remained mostly roadless. We recommend that forest-management policies make the preservation of large connected forest areas a top priority by effectively monitoring - and limiting - the occupation of space by roads that are permanently accessible. © 2016 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

  15. National forest cover change in Congo Basin: deforestation, reforestation, degradation and regeneration for the years 1990, 2000 and 2005.

    Science.gov (United States)

    Céline, Ernst; Philippe, Mayaux; Astrid, Verhegghen; Catherine, Bodart; Musampa, Christophe; Pierre, Defourny

    2013-04-01

    This research refers to an object-based automatic method combined with a national expert validation to produce regional and national forest cover change statistics over Congo Basin. A total of 547 sampling sites systematically distributed over the whole humid forest domain are required to cover the six Central African countries containing tropical moist forest. High resolution imagery is used to accurately estimate not only deforestation and reforestation but also degradation and regeneration. The overall method consists of four steps: (i) image automatic preprocessing and preinterpretation, (ii) interpretation by national expert, (iii) statistic computation and (iv) accuracy assessment. The annual rate of net deforestation in Congo Basin is estimated to 0.09% between 1990 and 2000 and of net degradation to 0.05%. Between 2000 and 2005, this unique exercise estimates annual net deforestation to 0.17% and annual net degradation to 0.09%. An accuracy assessment reveals that 92.7% of tree cover (TC) classes agree with independent expert interpretation. In the discussion, we underline the direct causes and the drivers of deforestation. Population density, small-scale agriculture, fuelwood collection and forest's accessibility are closely linked to deforestation, whereas timber extraction has no major impact on the reduction in the canopy cover. The analysis also shows the efficiency of protected areas to reduce deforestation. These results are expected to contribute to the discussion on the reduction in CO2 emissions from deforestation and forest degradation (REDD+) and serve as reference for the period. © 2012 Blackwell Publishing Ltd.

  16. Mapping Congo Basin vegetation types from 300 m and 1 km multi-sensor time series for carbon stocks and forest areas estimation

    Directory of Open Access Journals (Sweden)

    A. Verhegghen

    2012-12-01

    Full Text Available This study aims to contribute to the understanding of the Congo Basin forests by delivering a detailed map of vegetation types with an improved spatial discrimination and coherence for the whole Congo Basin region. A total of 20 land cover classes were described with the standardized Land Cover Classification System (LCCS developed by the FAO. Based on a semi-automatic processing chain, the Congo Basin vegetation types map was produced by combining 19 months of observations from the Envisat MERIS full resolution products (300 m and 8 yr of daily SPOT VEGETATION (VGT reflectances (1 km. Four zones (north, south and two central were delineated and processed separately according to their seasonal and cloud cover specificities. The discrimination between different vegetation types (e.g. forest and savannas was significantly improved thanks to the MERIS sharp spatial resolution. A better discrimination was achieved in cloudy areas by taking advantage of the temporal consistency of the SPOT VGT observations. This resulted in a precise delineation of the spatial extent of the rural complex in the countries situated along the Atlantic coast. Based on this new map, more accurate estimates of the surface areas of forest types were produced for each country of the Congo Basin. Carbon stocks of the Basin were evaluated to a total of 49 360 million metric tons. The regional scale of the map was an opportunity to investigate what could be an appropriate tree cover threshold for a forest class definition in the Congo Basin countries. A 30% tree cover threshold was suggested. Furthermore, the phenology of the different vegetation types was illustrated systematically with EVI temporal profiles. This Congo Basin forest types map reached a satisfactory overall accuracy of 71.5% and even 78.9% when some classes are aggregated. The values of the Cohen's kappa coefficient, respectively 0.64 and 0.76 indicates a result significantly better than random.

  17. Empty forests, empty stomachs? Bushmeat and livelihoods in the Congo and Amazon Basins

    DEFF Research Database (Denmark)

    Nasi, R.; Taber, A.; van Vliet, Nathalie

    2011-01-01

    Protein from forest wildlife is crucial to rural food security and livelihoods across the tropics. The harvest of animals such as tapir, duikers, deer, pigs, peccaries, primates and larger rodents, birds and reptiles provides benefits to local people worth millions of USS annually and represents...... around 6 million tonnes of animals extracted yearly. Vulnerability to hunting varies, with some species sustaining populations in heavily hunted secondary habitats, while others require intact forests with minimal harvesting to maintain healthy populations. Some species or groups have been characterized...

  18. Climatic and cultural changes in the west Congo Basin forests over the past 5000 years.

    Science.gov (United States)

    Oslisly, Richard; White, Lee; Bentaleb, Ilham; Favier, Charly; Fontugne, Michel; Gillet, Jean-François; Sebag, David

    2013-01-01

    Central Africa includes the world's second largest rainforest block. The ecology of the region remains poorly understood, as does its vegetation and archaeological history. However, over the past 20 years, multidisciplinary scientific programmes have enhanced knowledge of old human presence and palaeoenvironments in the forestry block of Central Africa. This first regional synthesis documents significant cultural changes over the past five millennia and describes how they are linked to climate. It is now well documented that climatic conditions in the African tropics underwent significant changes throughout this period and here we demonstrate that corresponding shifts in human demography have had a strong influence on the forests. The most influential event was the decline of the strong African monsoon in the Late Holocene, resulting in serious disturbance of the forest block around 3500 BP. During the same period, populations from the north settled in the forest zone; they mastered new technologies such as pottery and fabrication of polished stone tools, and seem to have practised agriculture. The opening up of forests from 2500 BP favoured the arrival of metallurgist populations that impacted the forest. During this long period (2500-1400 BP), a remarkable increase of archaeological sites is an indication of a demographic explosion of metallurgist populations. Paradoxically, we have found evidence of pearl millet (Pennisetum glaucum) cultivation in the forest around 2200 BP, implying a more arid context. While Early Iron Age sites (prior to 1400 BP) and recent pre-colonial sites (two to eight centuries BP) are abundant, the period between 1600 and 1000 BP is characterized by a sharp decrease in human settlements, with a population crash between 1300 and 1000 BP over a large part of Central Africa. It is only in the eleventh century that new populations of metallurgists settled into the forest block. In this paper, we analyse the spatial and temporal distribution

  19. Where artisanal mines and forest meet: Socio-economic and environmental impacts in the Congo Basin

    NARCIS (Netherlands)

    Ingram, V.J.; Tieguhong, J.C.; Schure, J.M.; Nkamgnia, E.; Tadjuidje, M.H.

    2011-01-01

    While mineral exploitation can provide significant income and employment, it may negatively impact the environment, being ultimately detrimental to livelihoods in the long term. The consequences of mining are of concern in high value forest ecosystems such as the Sangha Tri-National (TNS) landscape

  20. Climate Change Impacts on the Congo Basin Region

    NARCIS (Netherlands)

    Ludwig, F.; Franssen, W.; Jans, W.W.P.; Kruijt, B.; Supit, I.

    2012-01-01

    This report presents analyses of climate change impacts in the Congo Basin on water for agriculture and hydropower, forest ecosystem functioning and carbon storage and impacts of climate variability and change on future economic development. To quantify the impacts of future climate we developed a

  1. Shaping forest safety nets with markets: Adaptation to climate change under changing roles of tropical forests in Congo Basin

    NARCIS (Netherlands)

    Nkem, J.; Kalame, F.B.; Idinoba, M.; Somorin, O.A.; Ndoye, O.; Awono, A.

    2010-01-01

    Tropical forests hold several goods and services used by forest-dependent people as safety nets to traverse difficult periods of resource supply. These same goods and services are constantly surrounded by emerging markets linking remote communities with major urban centers nationally and

  2. Modelling the Congo basin ecosystems with a dynamic vegetation model

    Science.gov (United States)

    Dury, Marie; Hambuckers, Alain; Trolliet, Franck; Huynen, Marie-Claude; Haineaux, Damien; Fontaine, Corentin M.; Fayolle, Adeline; François, Louis

    2014-05-01

    The scarcity of field observations in some parts of the world makes difficult a deep understanding of some ecosystems such as humid tropical forests in Central Africa. Therefore, modelling tools are interesting alternatives to study those regions even if the lack of data often prevents sharp calibration and validation of the model projections. Dynamic vegetation models (DVMs) are process-based models that simulate shifts in potential vegetation and its associated biogeochemical and hydrological cycles in response to climate. Initially run at the global scale, DVMs can be run at any spatial scale provided that climate and soil data are available. In the framework of the BIOSERF project ("Sustainability of tropical forest biodiversity and services under climate and human pressure"), we use and adapt the CARAIB dynamic vegetation model (Dury et al., iForest - Biogeosciences and Forestry, 4:82-99, 2011) to study the Congo basin vegetation dynamics. The field campaigns have notably allowed the refinement of the vegetation representation from plant functional types (PFTs) to individual species through the collection of parameters such as the specific leaf area or the leaf C:N ratio of common tropical tree species and the location of their present-day occurrences from literature and available database. Here, we test the model ability to reproduce the present spatial and temporal variations of carbon stocks (e.g. biomass, soil carbon) and fluxes (e.g. gross and net primary productivities (GPP and NPP), net ecosystem production (NEP)) as well as the observed distribution of the studied species over the Congo basin. In the lack of abundant and long-term measurements, we compare model results with time series of remote sensing products (e.g. vegetation leaf area index (LAI), GPP and NPP). Several sensitivity tests are presented: we assess consecutively the impacts of the level at which the vegetation is simulated (PFTs or species), the spatial resolution and the initial land

  3. Tree Species Diversity, Richness, and Similarity in Intact and Degraded Forest in the Tropical Rainforest of the Congo Basin: Case of the Forest of Likouala in the Republic of Congo

    Directory of Open Access Journals (Sweden)

    Suspense Averti Ifo

    2016-01-01

    Full Text Available Trees species diversity, richness, and similarity were studied in fifteen plots of the tropical rainforests in the northeast of the Republic of Congo, based on trees inventories conducted on fifteen 0.25 ha plots installed along different types of forests developed on terra firma, seasonally flooded, and on flooded terra. In all of the plots installed, all trees with diameter at breast height, DBH ≥ 5 cm, were measured. The Shannon diversity index, species richness, equitability, and species dominance were computed to see the variation in tree community among plots but also between primary forest and secondary forest. A total of 1611 trees representing 114 species and 35 families were recorded from a total area of 3.75 ha. Euphorbiaceae was the dominant family in the forest with 12 species, followed by Fabaceae-Mimosoideae (10 species and Phyllanthaceae (6 species and Guttiferae (6 species. The biodiversity did not vary greatly from plot to plot on the whole of the study area (3.75 ha. The low value of Shannon index was obtained in plot 11 (H′=0.75 whereas the highest value was obtained in plot 12 (H′=4.46. The values of this index vary from 0.23 to 0.95 in plots P11 and P15, respectively. Results obtained revealed high biodiversity of trees of the forest of Impfondo-Dongou. The information on tree species structure and function can provide baseline information for conservation of the biodiversity of the tropical forest in this area.

  4. Production of animal protein in the Congo Basin, a challenge for the future of people and wildlife

    OpenAIRE

    Moula, Nassim; Hornick, Jean-Luc; Ruppol, Patrick; Antoine-Moussiaux, Nicolas; Leroy, Pascal

    2014-01-01

    Protein needs are considerable in the Congo Basin, a vast territory dominated by forest and inhabited by tens of millions of people. Whereas over 85% of the DRC’s population of the Basin live in the forest, the situation is different in other countries where the majority is urban (Cameroon, Central African Republic, Congo and Gabon). This paper presents several achievements of the Centre for Tropical Agriculture and Veterinary Medicine in Kinshasa (CAVTK), which aims since 2001 to conduct pil...

  5. Will Passive Protection Save Congo Forests?

    Science.gov (United States)

    Galford, Gillian L.; Soares-Filho, Britaldo S.; Sonter, Laura J.; Laporte, Nadine

    2015-01-01

    Central Africa’s tropical forests are among the world’s largest carbon reserves. Historically, they have experienced low rates of deforestation. Pressures to clear land are increasing due to development of infrastructure and livelihoods, foreign investment in agriculture, and shifting land use management, particularly in the Democratic Republic of Congo (DRC). The DRC contains the greatest area of intact African forests. These store approximately 22 billion tons of carbon in aboveground live biomass, yet only 10% are protected. Can the status quo of passive protection — forest management that is low or nonexistent — ensure the preservation of this forest and its carbon? We have developed the SimCongo model to simulate changes in land cover and land use based on theorized policy scenarios from 2010 to 2050. Three scenarios were examined: the first (Historical Trends) assumes passive forest protection; the next (Conservation) posits active protection of forests and activation of the national REDD+ action plan, and the last (Agricultural Development) assumes increased agricultural activities in forested land with concomitant increased deforestation. SimCongo is a cellular automata model based on Bayesian statistical methods tailored for the DRC, built with the Dinamica-EGO platform. The model is parameterized and validated with deforestation observations from the past and runs the scenarios from 2010 through 2050 with a yearly time step. We estimate the Historical Trends trajectory will result in average emissions of 139 million t CO2 year-1 by the 2040s, a 15% increase over current emissions. The Conservation scenario would result in 58% less clearing than Historical Trends and would conserve carbon-dense forest and woodland savanna areas. The Agricultural Development scenario leads to emissions of 212 million t CO2 year-1 by the 2040s. These scenarios are heuristic examples of policy’s influence on forest conservation and carbon storage. Our results

  6. To Tip or Not to Tip: The Case of the Congo Basin Rainforest Realm

    Science.gov (United States)

    Pietsch, S.; Bednar, J. E.; Fath, B. D.; Winter, P. A.

    2017-12-01

    The future response of the Congo basin rainforest, the second largest tropical carbon reservoir, to climate change is still under debate. Different Climate projections exist stating increase and decrease in rainfall and different changes in rainfall patterns. Within this study we assess all options of climate change possibilities to define the climatic thresholds of Congo basin rainforest stability and assess the limiting conditions for rainforest persistence. We use field data from 199 research plots from the Western Congo basin to calibrate and validate a complex BioGeoChemistry model (BGC-MAN) and assess model performance against an array of possible future climates. Next, we analyze the reasons for the occurrence of tipping points, their spatial and temporal probability of occurrence, will present effects of hysteresis and derive probabilistic spatial-temporal resilience landscapes for the region. Additionally, we will analyze attractors of forest growth dynamics and assess common linear measures for early warning signals of sudden shifts in system dynamics for their robustness in the context of the Congo Basin case, and introduce the correlation integral as a nonlinear measure of risk assessment.

  7. Changing governance arrangements: NTFP value chains in the Congo Basin

    NARCIS (Netherlands)

    Ingram, V.J.

    2017-01-01

    As forest products from Cameroon and DR Congo are commercialised, a value chain is created from harvesters, processors, and retailers to
    consumers worldwide. In contrast to dominant narratives focusing on regulations and customs, these chains are actually governed by dynamic,
    multiple

  8. Lesula: a new species of Cercopithecus monkey endemic to the Democratic Republic of Congo and implications for conservation of Congo's central basin.

    Directory of Open Access Journals (Sweden)

    John A Hart

    Full Text Available In June 2007, a previously undescribed monkey known locally as "lesula" was found in the forests of the middle Lomami Basin in central Democratic Republic of Congo (DRC. We describe this new species as Cercopithecus lomamiensis sp. nov., and provide data on its distribution, morphology, genetics, ecology and behavior. C. lomamiensis is restricted to the lowland rain forests of central DRC between the middle Lomami and the upper Tshuapa Rivers. Morphological and molecular data confirm that C. lomamiensis is distinct from its nearest congener, C. hamlyni, from which it is separated geographically by both the Congo (Lualaba and the Lomami Rivers. C. lomamiensis, like C. hamlyni, is semi-terrestrial with a diet containing terrestrial herbaceous vegetation. The discovery of C. lomamiensis highlights the biogeographic significance and importance for conservation of central Congo's interfluvial TL2 region, defined from the upper Tshuapa River through the Lomami Basin to the Congo (Lualaba River. The TL2 region has been found to contain a high diversity of anthropoid primates including three forms, in addition to C. lomamiensis, that are endemic to the area. We recommend the common name, lesula, for this new species, as it is the vernacular name used over most of its known range.

  9. Opportunities for Hydrologic Research in the Congo Basin

    Science.gov (United States)

    Alsdorf, D. E.; Beighley, E., II; Lee, H.; Tshimanga, R.; Spencer, R. G.; O'Loughlin, F.

    2014-12-01

    We review the published results on the Congo Basin hydrology and find that there are historic data, ongoing measurement recording efforts, and important model results. Annual rainfall is ~2000 mm/yr along an east-west trend, decreasing northward and southward to ~1100 mm/yr. While some studies show rain gauges at specific locations with declines in P greater than 10% from 1960 to 1990, other studies suggest that basin wide decreases from 1951 to 1993 are modest at 4.5% or that the trend is minimal. Studies during the 1950s using lysimeters, pans, and models suggest that the annual potential ET varies little across the basin at a 1100 mm/yr to 1200 mm/yr. Over the past century, river discharge data has been collected at 100s of stream gauges with historic and recent data at 96 locations now publicly available. Discharge of the Congo River at Kinshasa-Brazzaville experienced an increase of 21% during 1960-1970 in comparison to background values of the previous decades and of today. There does not appear to be a long-term discharge trend over the century of record. Satellite altimetry measurements collected during high and low flows show that the Cuvette Centrale wetland water levels are consistently 0.5m to 3m higher in elevation than the immediately adjacent Congo River levels. Wetland water depths are shallow at about 1m whereas the Congo is typically less than 15m deep everywhere upstream of Kinshasa. The wetlands do not appear to be marked by sizable channels such that the flows are diffusive. CO2 and CH4 evasion from the Congo waters directly to the atmosphere are estimated at 1.6 to 3.2 Tg/yr for CH4 from the Cuvette wetland waters and 105 to 204 g C/m2/yr for CO2 from waters of the Oubangui River. Using these published results, we suggest seven hypotheses that may lead to important water and carbon cycle discoveries. These hypotheses focus on the source of the Cuvette waters and how those waters leave the wetland; on river discharge generated by historic

  10. Congo Basin rainfall climatology: can we believe the climate models?

    Science.gov (United States)

    Washington, Richard; James, Rachel; Pearce, Helen; Pokam, Wilfried M; Moufouma-Okia, Wilfran

    2013-01-01

    The Congo Basin is one of three key convective regions on the planet which, during the transition seasons, dominates global tropical rainfall. There is little agreement as to the distribution and quantity of rainfall across the basin with datasets differing by an order of magnitude in some seasons. The location of maximum rainfall is in the far eastern sector of the basin in some datasets but the far western edge of the basin in others during March to May. There is no consistent pattern to this rainfall distribution in satellite or model datasets. Resolving these differences is difficult without ground-based data. Moisture flux nevertheless emerges as a useful variable with which to study these differences. Climate models with weak (strong) or even divergent moisture flux over the basin are dry (wet). The paper suggests an approach, via a targeted field campaign, for generating useful climate information with which to confront rainfall products and climate models.

  11. Water level fluctuations in the Congo basin derived from ENVISAT satellite altimetry

    OpenAIRE

    Becker, M.; da Silva, J. S.; Calmant, Stéphane; Robinet, V.; Linguet, L.; Seyler, Frédérique

    2014-01-01

    In the Congo Basin, the elevated vulnerability of food security and the water supply implies that sustainable development strategies must incorporate the effects of climate change on hydrological regimes. However, the lack of observational hydro-climatic data over the past decades strongly limits the number of studies investigating the effects of climate change in the Congo Basin. We present the largest altimetry-based dataset of water levels ever constituted over the entire Congo Basin. This...

  12. Congo Basin precipitation: Assessing seasonality, regional interactions, and sources of moisture

    Science.gov (United States)

    Dyer, Ellen L. E.; Jones, Dylan B. A.; Nusbaumer, Jesse; Li, Harry; Collins, Owen; Vettoretti, Guido; Noone, David

    2017-07-01

    Precipitation in the Congo Basin was examined using a version of the National Center for Atmospheric Research Community Earth System Model (CESM) with water tagging capability. Using regionally defined water tracers, or tags, the moisture contribution from different source regions to Congo Basin precipitation was investigated. We found that the Indian Ocean and evaporation from the Congo Basin were the dominant moisture sources and that the Atlantic Ocean was a comparatively small source of moisture. In both rainy seasons the southwestern Indian Ocean contributed about 21% of the moisture, while the recycling ratio for moisture from the Congo Basin was about 25%. Near the surface, a great deal of moisture is transported from the Atlantic into the Congo Basin, but much of this moisture is recirculated back over the Atlantic in the lower troposphere. Although the southwestern Indian Ocean is a major source of Indian Ocean moisture, it is not associated with the bulk of the variability in precipitation over the Congo Basin. In wet years, more of the precipitation in the Congo Basin is derived from Indian Ocean moisture, but the spatial distribution of the dominant sources is shifted, reflecting changes in the midtropospheric circulation over the Indian Ocean. During wet years there is increased transport of moisture from the equatorial and eastern Indian Ocean. Our results suggest that reliably capturing the linkages between the large-scale circulation patterns over the Indian Ocean and the local circulation over the Congo Basin is critical for future projections of Congo Basin precipitation.

  13. Age, extent and carbon storage of the central Congo Basin peatland complex.

    Science.gov (United States)

    Dargie, Greta C; Lewis, Simon L; Lawson, Ian T; Mitchard, Edward T A; Page, Susan E; Bocko, Yannick E; Ifo, Suspense A

    2017-02-02

    Peatlands are carbon-rich ecosystems that cover just three per cent of Earth's land surface, but store one-third of soil carbon. Peat soils are formed by the build-up of partially decomposed organic matter under waterlogged anoxic conditions. Most peat is found in cool climatic regions where unimpeded decomposition is slower, but deposits are also found under some tropical swamp forests. Here we present field measurements from one of the world's most extensive regions of swamp forest, the Cuvette Centrale depression in the central Congo Basin. We find extensive peat deposits beneath the swamp forest vegetation (peat defined as material with an organic matter content of at least 65 per cent to a depth of at least 0.3 metres). Radiocarbon dates indicate that peat began accumulating from about 10,600 years ago, coincident with the onset of more humid conditions in central Africa at the beginning of the Holocene. The peatlands occupy large interfluvial basins, and seem to be largely rain-fed and ombrotrophic-like (of low nutrient status) systems. Although the peat layer is relatively shallow (with a maximum depth of 5.9 metres and a median depth of 2.0 metres), by combining in situ and remotely sensed data, we estimate the area of peat to be approximately 145,500 square kilometres (95 per cent confidence interval of 131,900-156,400 square kilometres), making the Cuvette Centrale the most extensive peatland complex in the tropics. This area is more than five times the maximum possible area reported for the Congo Basin in a recent synthesis of pantropical peat extent. We estimate that the peatlands store approximately 30.6 petagrams (30.6 × 10 15  grams) of carbon belowground (95 per cent confidence interval of 6.3-46.8 petagrams of carbon)-a quantity that is similar to the above-ground carbon stocks of the tropical forests of the entire Congo Basin. Our result for the Cuvette Centrale increases the best estimate of global tropical peatland carbon stocks by

  14. The biogeochemistry of carbon across a gradient of streams and rivers within the Congo Basin

    Science.gov (United States)

    Mann, P. J.; Spencer, R. G. M.; Dinga, B. J.; Poulsen, J. R.; Hernes, P. J.; Fiske, G.; Salter, M. E.; Wang, Z. A.; Hoering, K. A.; Six, J.; Holmes, R. M.

    2014-04-01

    Dissolved organic carbon (DOC) and inorganic carbon (DIC, pCO2), lignin biomarkers, and theoptical properties of dissolved organic matter (DOM) were measured in a gradient of streams and rivers within the Congo Basin, with the aim of examining how vegetation cover and hydrology influences the composition and concentration of fluvial carbon (C). Three sampling campaigns (February 2010, November 2010, and August 2011) spanning 56 sites are compared by subbasin watershed land cover type (savannah, tropical forest, and swamp) and hydrologic regime (high, intermediate, and low). Land cover properties predominately controlled the amount and quality of DOC, chromophoric DOM (CDOM) and lignin phenol concentrations (∑8) exported in streams and rivers throughout the Congo Basin. Higher DIC concentrations and changing DOM composition (lower molecular weight, less aromatic C) during periods of low hydrologic flow indicated shifting rapid overland supply pathways in wet conditions to deeper groundwater inputs during drier periods. Lower DOC concentrations in forest and swamp subbasins were apparent with increasing catchment area, indicating enhanced DOC loss with extended water residence time. Surface water pCO2 in savannah and tropical forest catchments ranged between 2,600 and 11,922 µatm, with swamp regions exhibiting extremely high pCO2 (10,598-15,802 µatm), highlighting their potential as significant pathways for water-air efflux. Our data suggest that the quantity and quality of DOM exported to streams and rivers are largely driven by terrestrial ecosystem structure and that anthropogenic land use or climate change may impact fluvial C composition and reactivity, with ramifications for regional C budgets and future climate scenarios.

  15. Mapping Biomass for REDD in the Largest Forest of Central Africa: the Democratic Republic of Congo

    Science.gov (United States)

    Shapiro, Aurelie; Saatchi, Sassan

    2014-05-01

    With the support of the International Climate Initiative (ICI) of the Federal Ministry of the Environment, Conservation, and Nuclear Security, the implementation of the German Development Bank KfW, the World Wide Fund for Nature (WWF) Germany, the University of California Los Angeles (UCLA) and local DRC partners will produce a national scale biomass map for the entire forest coverage of the Democratic Republic of Congo (DRC) along with feasibility assessments of different forest protection measures within a framework of a REDD+ model project. The « Carbon Map and Model (CO2M&M) » project will produce a national forest biomass map for the DRC, which will enable quantitative assessments of carbon stocks and emissions in the largest forest of the Congo Basin. This effort will support the national REDD (Reducing Emissions from Deforestation and Degradation) program in DRC, which plays a major role in sustainable development and poverty alleviation. This map will be developed from field data, complemented by airborne LiDAR (Light Detection and Ranging) and aerial photos, systematically sampled throughout the forests of the DRC and up-scaled to satellite images to accurately estimate carbon content in all forested areas. The second component of the project is to develop specific approaches for model REDD projects in key landscapes. This project represents the largest LiDAR-derived mapping effort in Africa, under unprecedented logistical constraints, which will provide one of the poorest nations in the world with the richest airborne and satellites derived datasets for analyzing forest structure, biomass and biodiversity.

  16. Lightning climatology in the Congo Basin: detailed analysis

    Science.gov (United States)

    Soula, Serge; Kigotsi, Jean; Georgis, Jean-François; Barthe, Christelle

    2016-04-01

    The lightning climatology of the Congo Basin including several countries of Central Africa is analyzed in detail for the first time. It is based on World Wide Lightning Location Network (WWLLN) data for the period from 2005 to 2013. A comparison of these data with the Lightning Imaging Sensor (LIS) data for the same period shows the WWLLN detection efficiency (DE) in the region increases from about 1.70 % in the beginning of the period to 5.90 % in 2013, relative to LIS data, but not uniformly over the whole 2750 km × 2750 km area. Both the annual flash density and the number of stormy days show sharp maximum values localized in eastern of Democratic Republic of Congo (DRC) and west of Kivu Lake, regardless of the reference year and the period of the year. These maxima reach 12.86 fl km-2 and 189 days, respectively, in 2013, and correspond with a very active region located at the rear of the Virunga mountain range characterised with summits that can reach 3000 m. The presence of this range plays a role in the thunderstorm development along the year. The estimation of this local maximum of the lightning density by taking into account the DE, leads to a value consistent with that of the global climatology by Christian et al. (2003) and other authors. Thus, a mean maximum value of about 157 fl km-2 y-1 is found for the annual lightning density. The zonal distribution of the lightning flashes exhibits a maximum between 1°S and 2°S and about 56 % of the flashes located below the equator in the 10°S - 10°N interval. The diurnal evolution of the flash rate has a maximum between 1400 and 1700 UTC, according to the reference year, in agreement with previous works in other regions of the world.

  17. Water Level Fluctuations in the Congo Basin Derived from ENVISAT Satellite Altimetry

    Directory of Open Access Journals (Sweden)

    Mélanie Becker

    2014-09-01

    Full Text Available In the Congo Basin, the elevated vulnerability of food security and the water supply implies that sustainable development strategies must incorporate the effects of climate change on hydrological regimes. However, the lack of observational hydro-climatic data over the past decades strongly limits the number of studies investigating the effects of climate change in the Congo Basin. We present the largest altimetry-based dataset of water levels ever constituted over the entire Congo Basin. This dataset of water levels illuminates the hydrological regimes of various tributaries of the Congo River. A total of 140 water level time series are extracted using ENVISAT altimetry over the period of 2003 to 2009. To improve the understanding of the physical phenomena dominating the region, we perform a K-means cluster analysis of the altimeter-derived river level height variations to identify groups of hydrologically similar catchments. This analysis reveals nine distinct hydrological regions. The proposed regionalization scheme is validated and therefore considered reliable for estimating monthly water level variations in the Congo Basin. This result confirms the potential of satellite altimetry in monitoring spatio-temporal water level variations as a promising and unprecedented means for improved representation of the hydrologic characteristics in large ungauged river basins.

  18. Quelles sont les causes de la déforestation dans le bassin du Congo ? Synthèse bibliographique et études de cas

    Directory of Open Access Journals (Sweden)

    Gillet, P.

    2016-01-01

    Full Text Available Drivers of deforestation in the Congo basin tropical forest. A review. Description of the subject. The forests of the Congo Basin are among the best preserved areas on Earth. Nevertheless, the factors causing deforestation around the world are also present in this subregion. This document presents a literature review of the direct causes and underlying factors of deforestation in the tropical areas and highlights the drivers of deforestation in the Congo Basin and particularly in Cameroon and Gabon. Literature. Direct causes of deforestation, defined as having a direct cause-and-consequence connection with the destruction of forest cover, are underpinned by economic factors, technological developments, pro-deforestation policy measures and demographic pressures. These factors interact in different ways in the various tropical regions worldwide, which explains the differences and similarities of regional deforestation dynamics. Beside the expansion of infrastructure, the development of mining and timber extraction, agriculture is the main direct cause of deforestation in the Congo Basin. In Cameroon, the current deforestation is primarily driven by agriculture. The State emergency plan includes the development of infrastructure, the modernization of production, equipment and mining. The lack of strategy for rapidly changing demographics might be the most important underlying cause of deforestation. In Gabon, although the deforestation rate is low, agriculture and the opening of roads are main drivers. The emergency plan includes modernization of infrastructure and the development of agro-industrial agriculture. Conclusions. A mutation of socio-ecosystems is expected in different parts of the Congo Basin. Future research should now turn to the analysis of socio-ecosystems representative of the various stages of the forest transition and identify drivers of change at different scales.

  19. Financing and current capacity for REDD+ readiness and monitoring, measurement, reporting and verification in the Congo Basin.

    Science.gov (United States)

    Maniatis, Danae; Gaugris, Jérôme; Mollicone, Danilo; Scriven, Joel; Corblin, Alexis; Ndikumagenge, Cleto; Aquino, André; Crete, Philippe; Sanz-Sanchez, Maria-José

    2013-01-01

    This paper provides the first critical analysis of the financing and current capacity for REDD+ readiness in the Congo Basin, with a particular focus on the REDD+ component of national forest monitoring and measurement, reporting and verification (M&MRV). We focus on three areas of analysis: (i) general financing for REDD+ readiness especially M&MRV; (ii) capacity and information for REDD+ implementation and M&MRV; (iii) prospects and challenges for REDD+ and M&MRV readiness in terms of financing and capacity. For the first area of analysis, a REDD+ and M&MRV readiness financing database was created based on the information from the REDD+ voluntary database and Internet searches. For the second area of analysis, a qualitative approach to data collection was adopted (semi-structured interviews with key stakeholders, surveys and observations). All 10 countries were visited between 2010 and 2012. We find that: (i) a significant amount of REDD+ financing flows into the Congo Basin (±US$550 million or almost half of the REDD+ financing for the African continent); (ii) across countries, there is an important disequilibrium in terms of REDD+ and M&MRV readiness financing, political engagement, comprehension and capacity, which also appears to be a key barrier to countries receiving equal resources; (iii) most financing appears to go to smaller scale (subnational) REDD+ projects; (iv) four distinct country groups in terms of REDD+ readiness and M&MRV status are identified; and (v) the Congo Basin has a distinct opportunity to have a specific REDD+ financing window for large-scale and more targeted national REDD+ programmes through a specific fund for the region.

  20. Financing and current capacity for REDD+ readiness and monitoring, measurement, reporting and verification in the Congo Basin

    Science.gov (United States)

    Maniatis, Danae; Gaugris, Jérôme; Mollicone, Danilo; Scriven, Joel; Corblin, Alexis; Ndikumagenge, Cleto; Aquino, André; Crete, Philippe; Sanz-Sanchez, Maria-José

    2013-01-01

    This paper provides the first critical analysis of the financing and current capacity for REDD+ readiness in the Congo Basin, with a particular focus on the REDD+ component of national forest monitoring and measurement, reporting and verification (M&MRV). We focus on three areas of analysis: (i) general financing for REDD+ readiness especially M&MRV; (ii) capacity and information for REDD+ implementation and M&MRV; (iii) prospects and challenges for REDD+ and M&MRV readiness in terms of financing and capacity. For the first area of analysis, a REDD+ and M&MRV readiness financing database was created based on the information from the REDD+ voluntary database and Internet searches. For the second area of analysis, a qualitative approach to data collection was adopted (semi-structured interviews with key stakeholders, surveys and observations). All 10 countries were visited between 2010 and 2012. We find that: (i) a significant amount of REDD+ financing flows into the Congo Basin (±US$550 million or almost half of the REDD+ financing for the African continent); (ii) across countries, there is an important disequilibrium in terms of REDD+ and M&MRV readiness financing, political engagement, comprehension and capacity, which also appears to be a key barrier to countries receiving equal resources; (iii) most financing appears to go to smaller scale (subnational) REDD+ projects; (iv) four distinct country groups in terms of REDD+ readiness and M&MRV status are identified; and (v) the Congo Basin has a distinct opportunity to have a specific REDD+ financing window for large-scale and more targeted national REDD+ programmes through a specific fund for the region. PMID:23878337

  1. Mapping monkeypox transmission risk through time and space in the Congo Basin

    Science.gov (United States)

    Nakazawa, Yoshinori J.; Lash, R. Ryan; Carroll, Darin S.; Damon, Inger K.; Karem, Kevin L.; Reynolds, Mary G.; Osorio, Jorge E.; Rocke, Tonie E.; Malekani, Jean; Muyembe, Jean-Jacques; Formenty, Pierre; Peterson, A. Townsend

    2013-01-01

    Monkeypox is a major public health concern in the Congo Basin area, with changing patterns of human case occurrences reported in recent years. Whether this trend results from better surveillance and detection methods, reduced proportions of vaccinated vs. non-vaccinated human populations, or changing environmental conditions remains unclear. Our objective is to examine potential correlations between environment and transmission of monkeypox events in the Congo Basin. We created ecological niche models based on human cases reported in the Congo Basin by the World Health Organization at the end of the smallpox eradication campaign, in relation to remotely-sensed Normalized Difference Vegetation Index datasets from the same time period. These models predicted independent spatial subsets of monkeypox occurrences with high confidence; models were then projected onto parallel environmental datasets for the 2000s to create present-day monkeypox suitability maps. Recent trends in human monkeypox infection are associated with broad environmental changes across the Congo Basin. Our results demonstrate that ecological niche models provide useful tools for identification of areas suitable for transmission, even for poorly-known diseases like monkeypox.

  2. Characterization of Terrestrial Water Dynamics in the Congo Basin Using GRACE and Satellite Radar Altimetry

    Science.gov (United States)

    Lee, Lyongki; Beighley, R. Edward; Alsdorf, Douglas; Jung, Hahn Chul; Shum, C. K.; Duan, Jianbin; Guo, Junyi; Yamazaki, Dai; Andreadis, Konstantinos

    2011-01-01

    The Congo Basin is the world's third largest in size (approximately 3.7 million km^2), and second only to the Amazon River in discharge (approximately 40,200 cms annual average). However, the hydrological dynamics of seasonally flooded wetlands and floodplains remains poorly quantified. Here, we separate the Congo wetland into four 3 degree x 3 degree regions, and use remote sensing measurements (i.e., GRACE, satellite radar altimeter, GPCP, JERS-1, SRTM, and MODIS) to estimate the amounts of water filling and draining from the Congo wetland, and to determine the source of the water. We find that the amount of water annually filling and draining the Congo wetlands is 111 km^3, which is about one-third the size of the water volumes found on the mainstem Amazon floodplain. Based on amplitude comparisons among the water volume changes and timing comparisons among their fluxes, we conclude that the local upland runoff is the main source of the Congo wetland water, not the fluvial process of river-floodplain water exchange as in the Amazon. Our hydraulic analysis using altimeter measurements also supports our conclusion by demonstrating that water surface elevations in the wetlands are consistently higher than the adjacent river water levels. Our research also highlights differences in the hydrology and hydrodynamics between the Congo wetland and the mainstem Amazon floodplain.

  3. Statistics of Deep Convection in the Congo Basin Derived From High-Resolution Simulations.

    Science.gov (United States)

    White, B.; Stier, P.; Kipling, Z.; Gryspeerdt, E.; Taylor, S.

    2016-12-01

    Convection transports moisture, momentum, heat and aerosols through the troposphere, and so the temporal variability of convection is a major driver of global weather and climate. The Congo basin is home to some of the most intense convective activity on the planet and is under strong seasonal influence of biomass burning aerosol. However, deep convection in the Congo basin remains under studied compared to other regions of tropical storm systems, especially when compared to the neighbouring, relatively well-understood West African climate system. We use the WRF model to perform a high-resolution, cloud-system resolving simulation to investigate convective storm systems in the Congo. Our setup pushes the boundaries of current computational resources, using a 1 km grid length over a domain covering millions of square kilometres and for a time period of one month. This allows us to draw statistical conclusions on the nature of the simulated storm systems. Comparing data from satellite observations and the model enables us to quantify the diurnal variability of deep convection in the Congo basin. This approach allows us to evaluate our simulations despite the lack of in-situ observational data. This provides a more comprehensive analysis of the diurnal cycle than has previously been shown. Further, we show that high-resolution convection-permitting simulations performed over near-seasonal timescales can be used in conjunction with satellite observations as an effective tool to evaluate new convection parameterisations.

  4. Land Water Storage within the Congo Basin Inferred from GRACE Satellite Gravity Data

    Science.gov (United States)

    Crowley, John W.; Mitrovica, Jerry X.; Bailey, Richard C.; Tamisiea, Mark E.; Davis, James L.

    2006-01-01

    GRACE satellite gravity data is used to estimate terrestrial (surface plus ground) water storage within the Congo Basin in Africa for the period of April, 2002 - May, 2006. These estimates exhibit significant seasonal (30 +/- 6 mm of equivalent water thickness) and long-term trends, the latter yielding a total loss of approximately 280 km(exp 3) of water over the 50-month span of data. We also combine GRACE and precipitation data set (CMAP, TRMM) to explore the relative contributions of the source term to the seasonal hydrological balance within the Congo Basin. We find that the seasonal water storage tends to saturate for anomalies greater than 30-44 mm of equivalent water thickness. Furthermore, precipitation contributed roughly three times the peak water storage after anomalously rainy seasons, in early 2003 and 2005, implying an approximately 60-70% loss from runoff and evapotranspiration. Finally, a comparison of residual land water storage (monthly estimates minus best-fitting trends) in the Congo and Amazon Basins shows an anticorrelation, in agreement with the 'see-saw' variability inferred by others from runoff data.

  5. Satellite-based estimates of surface water dynamics in the Congo River Basin

    Science.gov (United States)

    Becker, M.; Papa, F.; Frappart, F.; Alsdorf, D.; Calmant, S.; da Silva, J. Santos; Prigent, C.; Seyler, F.

    2018-04-01

    In the Congo River Basin (CRB), due to the lack of contemporary in situ observations, there is a limited understanding of the large-scale variability of its present-day hydrologic components and their link with climate. In this context, remote sensing observations provide a unique opportunity to better characterize those dynamics. Analyzing the Global Inundation Extent Multi-Satellite (GIEMS) time series, we first show that surface water extent (SWE) exhibits marked seasonal patterns, well distributed along the major rivers and their tributaries, and with two annual maxima located: i) in the lakes region of the Lwalaba sub-basin and ii) in the "Cuvette Centrale", including Tumba and Mai-Ndombe Lakes. At an interannual time scale, we show that SWE variability is influenced by ENSO and the Indian Ocean dipole events. We then estimate water level maps and surface water storage (SWS) in floodplains, lakes, rivers and wetlands of the CRB, over the period 2003-2007, using a multi-satellite approach, which combines the GIEMS dataset with the water level measurements derived from the ENVISAT altimeter heights. The mean annual variation in SWS in the CRB is 81 ± 24 km3 and contributes to 19 ± 5% of the annual variations of GRACE-derived terrestrial water storage (33 ± 7% in the Middle Congo). It represents also ∼6 ± 2% of the annual water volume that flows from the Congo River into the Atlantic Ocean.

  6. The Upper Jurassic Stanleyville Group of the eastern Congo Basin: An example of perennial lacustrine system

    Science.gov (United States)

    Caillaud, Alexis; Blanpied, Christian; Delvaux, Damien

    2017-08-01

    The intracratonic Congo Basin, located in the Democratic Republic of Congo (DRC), is the largest sedimentary basin of Africa. The Jurassic strata outcrop along its eastern margin, south of Kisangani (formerly Stanleyville). In the last century, the Upper Jurassic Stanleyville Group was described as a lacustrine series containing a thin basal marine limestone designed as the ;Lime Fine; beds. Since the proposal of this early model, the depositional environment of the Stanleyville Group, and especially the possible marine incursion, has been debated, but without re-examining the existing cores, outcrop samples and historical fossils from the type location near Kisangani that are available at the Royal Museum for Central Africa (MRAC/KMMA, Tervuren, Belgium). In order to refine the former sedimentology, a series of nine exploration cores drilled in the Kisangani sub-basin have been described. This study aims at integrating sedimentary facies in existing sedimentary models and to discuss the hypothesis of the presence of Kimmeridgian marine deposits along the Congo River near Kisangani, a region which lies in the middle of the African continent. Eight facies have been identified, which permit a reinterpretation of the depositional environment and paleogeography of the Stanleyville Group. The base of the Stanleyville Group is interpreted to represent a conglomeratic fluvial succession, which filled an inherited Triassic paleotopography. Above these conglomerates, a transition to a typically lacustrine system is interpreted, which includes: (1) a basal profundal, sublittoral (brown to dark fine-grained siltstones with microbial carbonates, i.e., the ;Lime Fine; beds) and littoral lacustrine series; covered by (2) a sublittoral to profundal interval (brown to dark organic-rich, fine-grained siltstones), which corresponds to the maximum extent of the paleo-lake; and, finally (3) a shallow lacustrine series (greenish calcareous siltstones and sandstones with red siltstones

  7. Generating daily weather data for ecosystem modelling in the Congo River Basin

    Science.gov (United States)

    Petritsch, Richard; Pietsch, Stephan A.

    2010-05-01

    Daily weather data are an important constraint for diverse applications in ecosystem research. In particular, temperature and precipitation are the main drivers for forest ecosystem productivity. Mechanistic modelling theory heavily relies on daily values for minimum and maximum temperatures, precipitation, incident solar radiation and vapour pressure deficit. Although the number of climate measurement stations increased during the last centuries, there are still regions with limited climate data. For example, in the WMO database there are only 16 stations located in Gabon with daily weather measurements. Additionally, the available time series are heavily affected by measurement errors or missing values. In the WMO record for Gabon, on average every second day is missing. Monthly means are more robust and may be estimated over larger areas. Therefore, a good alternative is to interpolate monthly mean values using a sparse network of measurement stations, and based on these monthly data generate daily weather data with defined characteristics. The weather generator MarkSim was developed to produce climatological time series for crop modelling in the tropics. It provides daily values for maximum and minimum temperature, precipitation and solar radiation. The monthly means can either be derived from the internal climate surfaces or prescribed as additional inputs. We compared the generated outputs observations from three climate stations in Gabon (Lastourville, Moanda and Mouilla) and found that maximum temperature and solar radiation were heavily overestimated during the long dry season. This is due to the internal dependency of the solar radiation estimates to precipitation. With no precipitation a cloudless sky is assumed and thus high incident solar radiation and a large diurnal temperature range. However, in reality it is cloudy in the Congo River Basin during the long dry season. Therefore, we applied a correction factor to solar radiation and temperature range

  8. Angola: source rock control for Lower Congo Coastal and Kwanza Basin petroleum systems

    Energy Technology Data Exchange (ETDEWEB)

    Burwood, R. [Fina Exploration Ltd, Epsom (United Kingdom)

    1999-07-01

    The purpose of this paper is to provide an overview of petroleum occurrence and provenance for the 1000 km West African Atlantic Margin from Cabinda to mid-Angola. Over this margin the Lower Congo Coastal and Kwanza provinces cumulatively account for reserves of c. 6 gigabarrels oil recoverable (GBOR). These are dominantly reservoired in Pinda carbonate traps of the former basin. However, with production from a range of aggradational wedge, carbonate platform and pre-salt reservoirs, a diversity in oil character presupposes complex hydrocarbon habitats charged by multiple sourcing. Each of these two major Atlantic margin salt basins constitutes a different, source rock driven, hydrocarbon habitat. As classic passive margin pull-apart basins, Early Cretaceous initiated rift events (Pre-rift, Syn-rift I, II, etc.) evolved into the drift phase opening of the southern Atlantic. A striking feature of this progression was widespread evaporite deposition of the Aptian Loeme salt. This separates two distinct sedimentary and tectonic domains of the Pre- and Post-Salt. The core Lower Congo Coastal habitat is dominated by the Pre-Salt Bucomazi Formation sourced 'poly' petroleum system. These lacustrine, often super-rich, sediments reveal considerable organofacies variation between their basin fill (Syn-rift I) and sheet drape (Syn-rift II) development, accounting for the compositional diversity in their progenic petroleums. Of crucial impact is a cognate diversity in their kerogen kinetic behaviour. This controls the conditions and timing of generation and realization of charge potential. With the Lower Congo Coastal habitat extending southwards towards the Ambriz Spur, the Bucomazi facies proper appears restricted to the northern and deeper proto-lake trend. Over the more weakly subsident margins such troughs host inferior sheet drape potential. Elswhere, Upper Cretaceous-Palaeogene marine clastic Iabe Formation sourced petroleum systems are hydrocarbon productive

  9. Remotely Sensed Based Lake/Reservoir Routing in Congo River Basin

    Science.gov (United States)

    Raoufi, R.; Beighley, E.; Lee, H.

    2017-12-01

    Lake and reservoir dynamics can influence local to regional water cycles but are often not well represented in hydrologic models. One challenge that limits their inclusion in models is the need for detailed storage-discharge behavior that can be further complicated in reservoirs where specific operation rules are employed. Here, the Hillslope River Routing (HRR) model is combined with a remotely sensed based Reservoir Routing (RR) method and applied to the Congo River Basin. Given that topographic data are often continuous over the entire terrestrial surface (i.e., does not differentiate between land and open water), the HRR-RR model integrates topographic derived river networks and catchment boundaries (e.g., HydroSHEDs) with water boundary extents (e.g., Global Lakes and Wetlands Database) to develop the computational framework. The catchments bordering lakes and reservoirs are partitioned into water and land portions, where representative flowpath characteristics are determined and vertical water balance and lateral routings is performed separately on each partition based on applicable process models (e.g., open water evaporation vs. evapotranspiration). To enable reservoir routing, remotely sensed water surface elevations and extents are combined to determine the storage change time series. Based on the available time series, representative storage change patterns are determined. Lake/reservoir routing is performed by combining inflows from the HRR-RR model and the representative storage change patterns to determine outflows. In this study, a suite of storage change patterns derived from remotely sensed measurements are determined representative patterns for wet, dry and average conditions. The HRR-RR model dynamically selects and uses the optimal storage change pattern for the routing process based on these hydrologic conditions. The HRR-RR model results are presented to highlight the importance of lake attenuation/routing in the Congo Basin.

  10. New data on the morphology and distribution of the enigmatic Schouteden's sun snake, Helophis schoutedeni (de Witte, 1922) from the Congo Basin

    Czech Academy of Sciences Publication Activity Database

    Nagy, Z. T.; Gvoždík, Václav; Meirte, D.; Collet, M.; Pauwels, O. S. G.

    2014-01-01

    Roč. 3755, č. 1 (2014), s. 96-100 ISSN 1175-5326 Institutional support: RVO:68081766 Keywords : Helophis * morphology * distribution * Congo Basin Subject RIV: EG - Zoology Impact factor: 0.906, year: 2014

  11. A Lagrangian perspective of the hydrological cycle in the Congo River basin

    Directory of Open Access Journals (Sweden)

    R. Sorí

    2017-08-01

    Full Text Available The Lagrangian model FLEXPART is used to identify the moisture sources of the Congo River basin (CRB and investigate their role in the hydrological cycle. This model allows us to track atmospheric parcels while calculating changes in the specific humidity through the budget of evaporation minus precipitation. This method permits the annual-scale identification of five continental and four oceanic principal regions that provide moisture to the CRB from both hemispheres over the course of the year. The most important is the CRB, which provides more than 50 % of the total atmospheric moisture contribution to precipitation over itself. Additionally, both the land that extends to the east of the CRB and the eastern equatorial South Atlantic Ocean are very important sources, while the Red Sea source is merely important in the (E − P budget over the CRB despite its high evaporation rate. The moisture-sink patterns over the CRB in air masses that were tracked forward in time from all the sources follow the latitudinal rainfall migration and are mostly highly correlated with the pattern of the precipitation rate, ensuring a link between them. In wet (dry years, the contribution of moisture to precipitation from the CRB over itself increases (decreases. Despite the enhanced evaporative conditions over the basin during dry years, the vertically integrated moisture flux (VIMF divergence inhibits precipitation and suggests the transport of moisture from the CRB to remote regions.

  12. Organic carbon accumulation in modern sediments of the Angola basin influenced by the Congo deep-sea fan

    Science.gov (United States)

    Baudin, François; Martinez, Philippe; Dennielou, Bernard; Charlier, Karine; Marsset, Tania; Droz, Laurence; Rabouille, Christophe

    2017-08-01

    Geochemical data (total organic carbon-TOC content, δ13Corg, C:N, Rock-Eval analyses) were obtained on 150 core tops from the Angola basin, with a special focus on the Congo deep-sea fan. Combined with the previously published data, the resulting dataset (322 stations) shows a good spatial and bathymetric representativeness. TOC content and δ13Corg maps of the Angola basin were generated using this enhanced dataset. The main difference in our map with previously published ones is the high terrestrial organic matter content observed downslope along the active turbidite channel of the Congo deep-sea fan till the distal lobe complex near 5000 m of water-depth. Interpretation of downslope trends in TOC content and organic matter composition indicates that lateral particle transport by turbidity currents is the primary mechanism controlling supply and burial of organic matter in the bathypelagic depths.

  13. Altering the Climate of Poverty under Climate Change : the Forests ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    This project aims to underscore the importance of the Congo basin forests in climate ... Shaping forest safety nets with markets : adaptation to climate change under changing roles ... Driving vaccine innovations to improve lives and livelihoods.

  14. Small-scale production in the Congo basin of low-acid carotene-rich red palm oil

    Directory of Open Access Journals (Sweden)

    Silou Thomas

    2017-09-01

    Full Text Available The red palm oil consumed in the Congo basin come essentially from small-scale production from the dura or tenera varieties (the latter being a hybrid of dura and pisifera. These three varieties are endemic to the Congo basin. The tenera variety is characterized a thick pulp (about 50% of the nut from which 70–90% of oil (based on fresh pulp can be extracted. The dura variety has less pulp (30% of the nut by weight, and gives an oil yield of the same order of magnitude. The oil is extracted from the crushed pulp after a series of mixing steps in hot water at about 60 °C. When obtained from freshly harvested nuts (at most 3 days storage, this oil is rich in carotenoids (800–2600 ppm and polyphenols (5–13 mg/g, and presents low acid values (IA < 5 and peroxide values (IP < 10. Here we describe this traditional production process, widespread in the Congo basin, and suggest innovations that substantially increase the quantity of oil extracted and significantly improve the quality of the end product.

  15. Combining satellite, aerial and ground measurements to assess forest carbon stocks in Democratic Republic of Congo

    Science.gov (United States)

    Beaumont, Benjamin; Bouvy, Alban; Stephenne, Nathalie; Mathoux, Pierre; Bastin, Jean-François; Baudot, Yves; Akkermans, Tom

    2015-04-01

    Monitoring tropical forest carbon stocks changes has been a rising topic in the recent years as a result of REDD+ mechanisms negotiations. Such monitoring will be mandatory for each project/country willing to benefit from these financial incentives in the future. Aerial and satellite remote sensing technologies offer cost advantages in implementing large scale forest inventories. Despite the recent progress made in the use of airborne LiDAR for carbon stocks estimation, no widely operational and cost effective method has yet been delivered for central Africa forest monitoring. Within the Maï Ndombe region of Democratic Republic of Congo, the EO4REDD project develops a method combining satellite, aerial and ground measurements. This combination is done in three steps: [1] mapping and quantifying forest cover changes using an object-based semi-automatic change detection (deforestation and forest degradation) methodology based on very high resolution satellite imagery (RapidEye), [2] developing an allometric linear model for above ground biomass measurements based on dendrometric parameters (tree crown areas and heights) extracted from airborne stereoscopic image pairs and calibrated using ground measurements of individual trees on a data set of 18 one hectare plots and [3] relating these two products to assess carbon stocks changes at a regional scale. Given the high accuracies obtained in [1] (> 80% for deforestation and 77% for forest degradation) and the suitable, but still to be improved with a larger calibrating sample, model (R² of 0.7) obtained in [2], EO4REDD products can be seen as a valid and replicable option for carbon stocks monitoring in tropical forests. Further improvements are planned to strengthen the cost effectiveness value and the REDD+ suitability in the second phase of EO4REDD. This second phase will include [A] specific model developments per forest type; [B] measurements of afforestation, reforestation and natural regeneration processes and

  16. In silico drug metabolism and pharmacokinetic profiles of natural products from medicinal plants in the Congo basin.

    Science.gov (United States)

    Ntie-Kang, Fidele; Lifongo, Lydia L; Mbah, James A; Owono Owono, Luc C; Megnassan, Eugene; Mbaze, Luc Meva'a; Judson, Philip N; Sippl, Wolfgang; Efange, Simon M N

    2013-01-01

    Drug metabolism and pharmacokinetics (DMPK) assessment has come to occupy a place of interest during the early stages of drug discovery today. The use of computer modelling to predict the DMPK and toxicity properties of a natural product library derived from medicinal plants from Central Africa (named ConMedNP). Material from some of the plant sources are currently employed in African Traditional Medicine. Computer-based methods are slowly gaining ground in this area and are often used as preliminary criteria for the elimination of compounds likely to present uninteresting pharmacokinetic profiles and unacceptable levels of toxicity from the list of potential drug candidates, hence cutting down the cost of discovery of a drug. In the present study, we present an in silico assessment of the DMPK and toxicity profile of a natural product library containing ~3,200 compounds, derived from 379 species of medicinal plants from 10 countries in the Congo Basin forests and savannas, which have been published in the literature. In this analysis, we have used 46 computed physico-chemical properties or molecular descriptors to predict the absorption, distribution, metabolism and elimination and toxicity (ADMET) of the compounds. This survey demonstrated that about 45% of the compounds within the ConMedNP compound library are compliant, having properties which fall within the range of ADME properties of 95% of currently known drugs, while about 69% of the compounds have ≤ 2 violations. Moreover, about 73% of the compounds within the corresponding "drug-like" subset showed compliance. In addition to the verified levels of "drug-likeness", diversity and the wide range of measured biological activities, the compounds from medicinal plants in Central Africa show interesting DMPK profiles and hence could represent an important starting point for hit/lead discovery.

  17. Microgeographical distribution of shrews (Mammalia, Soricidae) in the Congo River basin (Kisangani, D.R. Congo)

    DEFF Research Database (Denmark)

    Gambalemoke, Mbalitini; Mukinzi, Itoka; Amundala, Drazo

    2008-01-01

    Research on the biodiversity of shrews was conducted in eight forest blocks at eight sampling localities: Djabir, Maiko, Masako, Yoko, Yelenge, Baliko, Bomane-1 and Bomane-2. We used pitfall traps combined with Sherman LFA traps placed on transects. We collected 724 shrews from primary forests, s...

  18. Gendered forests: exploring gender dimensions in forest governance and REDD+ in Équateur Province, Democratic Republic of Congo (DRC

    Directory of Open Access Journals (Sweden)

    Raymond Achu Samndong

    2017-12-01

    Full Text Available In this study we analyze gender relations legitimatized by socio-political institutions of forest governance in REDD+ pilots in Équateur Province of the Democratic Republic of Congo. Using data from interviews, focus group discussions, and field observations, we show that men and women have different knowledge and use of forests, but these differences are not given due consideration in forest governance. Women's voices are often muted in decision-making arenas and they occupy only a nominal position in both forestry and development initiatives as compared with men. This status quo is extended to the REDD+ pilot projects as well. Women have limited information about REDD+ compared with men. The mechanisms used to establish new village organization for REDD+ exclude women from decision making in the ongoing REDD+ pilot project. We show that women's bargaining power for equal inclusion in decision-making processes and for sharing benefits are constrained by existing social norms regarding local access to land and material resources, existing gender division of labor, local perceptions regarding women's roles and contributions/responsibilities, as well as men's dominant position in rural settings. For a gender transformative REDD+, we suggest that REDD+ actors should attempt to bring about institutional changes that transform gender relations and thereby increase women's bargaining power.

  19. Simulated hydrologic response to projected changes in precipitation and temperature in the Congo River basin

    Directory of Open Access Journals (Sweden)

    N. Aloysius

    2017-08-01

    Full Text Available Despite their global significance, the impacts of climate change on water resources and associated ecosystem services in the Congo River basin (CRB have been understudied. Of particular need for decision makers is the availability of spatial and temporal variability of runoff projections. Here, with the aid of a spatially explicit hydrological model forced with precipitation and temperature projections from 25 global climate models (GCMs under two greenhouse gas emission scenarios, we explore the variability in modeled runoff in the near future (2016–2035 and mid-century (2046–2065. We find that total runoff from the CRB is projected to increase by 5 % [−9 %; 20 %] (mean – min and max – across model ensembles over the next two decades and by 7 % [−12 %; 24 %] by mid-century. Projected changes in runoff from subwatersheds distributed within the CRB vary in magnitude and sign. Over the equatorial region and in parts of northern and southwestern CRB, most models project an overall increase in precipitation and, subsequently, runoff. A simulated decrease in precipitation leads to a decline in runoff from headwater regions located in the northeastern and southeastern CRB. Climate model selection plays an important role in future projections for both magnitude and direction of change. The multimodel ensemble approach reveals that precipitation and runoff changes under business-as-usual and avoided greenhouse gas emission scenarios (RCP8.5 vs. RCP4.5 are relatively similar in the near term but deviate in the midterm, which underscores the need for rapid action on climate change adaptation. Our assessment demonstrates the need to include uncertainties in climate model and emission scenario selection during decision-making processes related to climate change mitigation and adaptation.

  20. Simulated hydrologic response to projected changes in precipitation and temperature in the Congo River basin

    Science.gov (United States)

    Aloysius, Noel; Saiers, James

    2017-08-01

    Despite their global significance, the impacts of climate change on water resources and associated ecosystem services in the Congo River basin (CRB) have been understudied. Of particular need for decision makers is the availability of spatial and temporal variability of runoff projections. Here, with the aid of a spatially explicit hydrological model forced with precipitation and temperature projections from 25 global climate models (GCMs) under two greenhouse gas emission scenarios, we explore the variability in modeled runoff in the near future (2016-2035) and mid-century (2046-2065). We find that total runoff from the CRB is projected to increase by 5 % [-9 %; 20 %] (mean - min and max - across model ensembles) over the next two decades and by 7 % [-12 %; 24 %] by mid-century. Projected changes in runoff from subwatersheds distributed within the CRB vary in magnitude and sign. Over the equatorial region and in parts of northern and southwestern CRB, most models project an overall increase in precipitation and, subsequently, runoff. A simulated decrease in precipitation leads to a decline in runoff from headwater regions located in the northeastern and southeastern CRB. Climate model selection plays an important role in future projections for both magnitude and direction of change. The multimodel ensemble approach reveals that precipitation and runoff changes under business-as-usual and avoided greenhouse gas emission scenarios (RCP8.5 vs. RCP4.5) are relatively similar in the near term but deviate in the midterm, which underscores the need for rapid action on climate change adaptation. Our assessment demonstrates the need to include uncertainties in climate model and emission scenario selection during decision-making processes related to climate change mitigation and adaptation.

  1. On Intensive Late Holocene Iron Mining and Production in the Northern Congo Basin and the Environmental Consequences Associated with Metallurgy in Central Africa

    Science.gov (United States)

    Lupo, Karen D.; Schmitt, Dave N.; Kiahtipes, Christopher A.; Ndanga, Jean-Paul; Young, D. Craig; Simiti, Bernard

    2015-01-01

    An ongoing question in paleoenvironmental reconstructions of the central African rainforest concerns the role that prehistoric metallurgy played in shaping forest vegetation. Here we report evidence of intensive iron-ore mining and smelting in forested regions of the northern Congo Basin dating to the late Holocene. Volumetric estimates on extracted iron-ore and associated slag mounds from prehistoric sites in the southern Central African Republic suggest large-scale iron production on par with other archaeological and historically-known iron fabrication areas. These data document the first evidence of intensive iron mining and production spanning approximately 90 years prior to colonial occupation (circa AD 1889) and during an interval of time that is poorly represented in the archaeological record. Additional site areas pre-dating these remains by 3-4 centuries reflect an earlier period of iron production on a smaller scale. Microbotanical evidence from a sediment core collected from an adjacent riparian trap shows a reduction in shade-demanding trees in concert with an increase in light-demanding species spanning the time interval associated with iron intensification. This shift occurs during the same time interval when many portions of the Central African witnessed forest transgressions associated with a return to moister and more humid conditions beginning 500-100 years ago. Although data presented here do not demonstrate that iron smelting activities caused widespread vegetation change in Central Africa, we argue that intense mining and smelting can have localized and potentially regional impacts on vegetation communities. These data further demonstrate the high value of pairing archeological and paleoenvironmental analyses to reconstruct regional-scale forest histories. PMID:26161540

  2. On Intensive Late Holocene Iron Mining and Production in the Northern Congo Basin and the Environmental Consequences Associated with Metallurgy in Central Africa.

    Science.gov (United States)

    Lupo, Karen D; Schmitt, Dave N; Kiahtipes, Christopher A; Ndanga, Jean-Paul; Young, D Craig; Simiti, Bernard

    2015-01-01

    An ongoing question in paleoenvironmental reconstructions of the central African rainforest concerns the role that prehistoric metallurgy played in shaping forest vegetation. Here we report evidence of intensive iron-ore mining and smelting in forested regions of the northern Congo Basin dating to the late Holocene. Volumetric estimates on extracted iron-ore and associated slag mounds from prehistoric sites in the southern Central African Republic suggest large-scale iron production on par with other archaeological and historically-known iron fabrication areas. These data document the first evidence of intensive iron mining and production spanning approximately 90 years prior to colonial occupation (circa AD 1889) and during an interval of time that is poorly represented in the archaeological record. Additional site areas pre-dating these remains by 3-4 centuries reflect an earlier period of iron production on a smaller scale. Microbotanical evidence from a sediment core collected from an adjacent riparian trap shows a reduction in shade-demanding trees in concert with an increase in light-demanding species spanning the time interval associated with iron intensification. This shift occurs during the same time interval when many portions of the Central African witnessed forest transgressions associated with a return to moister and more humid conditions beginning 500-100 years ago. Although data presented here do not demonstrate that iron smelting activities caused widespread vegetation change in Central Africa, we argue that intense mining and smelting can have localized and potentially regional impacts on vegetation communities. These data further demonstrate the high value of pairing archeological and paleoenvironmental analyses to reconstruct regional-scale forest histories.

  3. Comparison of West African and Congo Basin monkeypox viruses in BALB/c and C57BL/6 mice.

    Directory of Open Access Journals (Sweden)

    Christina L Hutson

    2010-01-01

    Full Text Available Although monkeypox virus (MPXV studies in wild rodents and non-human primates have generated important knowledge regarding MPXV pathogenesis and inferences about disease transmission, it might be easier to dissect the importance of virulence factors and correlates of protection to MPXV in an inbred mouse model. Herein, we compared the two clades of MPXV via two routes of infection in the BALB/c and C57BL/6 inbred mice strains. Our studies show that similar to previous animal studies, the Congo Basin strain of MPXV was more virulent than West African MPXV in both mouse strains as evidenced by clinical signs. Although animals did not develop lesions as seen in human MPX infections, localized signs were apparent with the foot pad route of inoculation, primarily in the form of edema at the site of inoculation; while the Congo Basin intranasal route of infection led to generalized symptoms, primarily weight loss. We have determined that future studies with MPXV and laboratory mice would be very beneficial in understanding the pathogenesis of MPXV, in particular if used in in vivo imaging studies. Although this mouse model may not suffice as a model of human MPX disease, with an appropriate inbred mouse model, we can unravel many unknown aspects of MPX pathogenesis, including virulence factors, disease progression in rodent hosts, and viral shedding from infected animals. In addition, such a model can be utilized to test antivirals and the next generation of orthopoxvirus vaccines for their ability to alter the course of disease.

  4. Hydroclimatic Change in the Congo River Basin: Past, Present and Future169

    Science.gov (United States)

    Aloysius, N. R.

    2016-12-01

    Tropical regions provide habitat for the world's most diverse fauna and flora, sequester more atmospheric carbon and provide livelihood for millions of people. The hydrological cycle provides vital linkages for maintaining these ecosystem functions, yet, the understanding of its spatiotemporal variability is limited. Research on the hydrological cycle of the Congo River Basin (CRB), which encompasses the second largest rainforests, has been largely ignored. Global Climate Models (GCM) show limited skills in simulating CRB's climate and their future projections vary widely. Yet, GCMs provide the most plausible scenarios of future climate, based upon which changes in hydrologic fluxes can be predicted with the aid hydrological models. In order to address the gaps in knowledge and to highlight the research needs, we i) developed a spatially explicit hydrological model suitable for describing key hydrological processes, ii) evaluated the performance of GCMs in simulating precipitation and temperature in the region, iii) developed a set of climate change scenarios for the CRB and iv) developed a simplified modeling framework to quantify water management options for rain-fed agriculture with the objective of achieving the triple goals of sustainable development: food security, poverty alleviation and ecosystem conservation. The hydrology model, which was validated with observed stream flows at 50 locations, satisfactorily characterizes spatiotemporal variability of key fluxes. Our evaluation of 25 GCM outputs reveal that many GCMs poorly simulate regional precipitation. We implemented a statistical bias-correction method to develop precipitation and temperature projections for two future greenhouse gas emission scenarios. These climate forcings were, then, used to drive the hydrology model. Our results show that the near-term projections are not affected by emission scenarios. However, towards the mid-21st century, projections are emission scenario dependent. Available

  5. Comparison of lightning activity in the two most active areas of the Congo Basin

    Science.gov (United States)

    Kigotsi, Jean K.; Soula, Serge; Georgis, Jean-François

    2018-02-01

    A comparison of the lightning activity in the two most active areas (Area_max for the main maximum and Area_sec for the secondary maximum) of the Congo Basin is made with data obtained by the World Wide Lightning Location Network (WWLLN) during 2012 and 2013. Both areas of same size (5° × 5°) exhibit flash counts in a ratio of about 1.32 for both years and very different distributions of the flash rate density (FRD) with maximums in a ratio of 1.94 and 2.59 for 2012 and 2013, respectively. The FRD is much more widely distributed in Area_sec, which means the whole area contributes more or less equal to the lightning activity. The diurnal cycle is much more pronounced in Area_max than in Area_sec with a ratio between the maximum and the minimum of 15.4 and 4.7, respectively. However, the minimum and maximum of the hourly flash rates are observed roughly at the same time in both areas, between 07:00 and 09:00 UTC and between 16:00 and 17:00 UTC, respectively. In Area_sec the proportion of days with low lightning rate (0-1000 flashes per day) is much larger (˜ 45 % in 2013) compared to Area_max (˜ 23 % in 2013). In Area_max the proportion of days with moderate lightning rate (1001-6000 flashes per day) is larger (˜ 68.5 % in 2013) compared to Area_sec (˜ 46 % in 2013). The very intense convective events are slightly more numerous in Area_sec. In summary, the thunderstorm activity in Area_sec is more variable at different scales of time (annually and daily), in intensity and in location. Area_max combines two favourable effects for thunderstorm development, the convergence associated with the African easterly jet of the Southern Hemisphere (AEJ-S) and a geographic effect due to the orography and the presence of a lake. The location of the strong convection in Area_sec is modulated by the distance of westward propagation/regeneration of mesoscale convective systems (MCSs) in relation to the phase of Kelvin waves.

  6. Attitudes Towards Forest Elephant Conservation Around a Protected Area in Northern Congo

    Directory of Open Access Journals (Sweden)

    Félicien Nsonsi

    2017-01-01

    Full Text Available An assessment of local attitudes towards conservation can guide wildlife managers in the effective application of measurements to improve these perceptions. Here we conducted a quantitative questionnaire survey around a protected area in northern Congo surveying 314 households living in four villages around the Nouabalé-Ndoki National Park. We investigated the impact of the benefits of a conservation project (led by an international non-governmental organisation, the experience with human-elephant conflict and the respondents' socio-economic profile on local people's attitudes towards forest elephant conservation. Using multivariate analysis, we found overall positive attitudes towards elephant conservation with more positive answers in the village where a conservation project is based. Furthermore, people employed in the conservation project stated more positive attitudes compared to logging company employees famers, natural resource users and people conducting other jobs. Experience of human elephant conflict negatively impacted people's perceptions. Socio-economic variables, such as ethnic group, education level or salary category had relatively little impact on people's responses. Qualitative statements largely supported the questionnaire results. We discuss our results in the light of the limits of attitude surveys and suggest further investigations to identify the activities needed to foster positive attitudes for elephant conservation in all villages around the Nouabalé-Ndoki National Park in partnership with the logging company.

  7. Charcoal records reveal past occurrences of disturbances in the forests of the Kisangani region, Democratic Republic of the Congo

    Science.gov (United States)

    Tshibamba Mukendi, John; Hubau, Wannes; Ntahobavuka, Honorine; Boyemba Bosela, Faustin; De Cannière, Charles; Beeckman, Hans

    2014-05-01

    Past disturbances have modified local density, structure and floristic composition of Central African rainforests. As such, these perturbations represent a driving force for forest dynamics and they were presumably at the origin of present-day forest mosaics. One of the most prominent disturbances within the forest is fire, leaving behind charcoal as a witness of past forest dynamics. Quantification and identification of ancient charcoal fragments found in soil layers (= pedoanthracology) allows a detailed reconstruction of forest history, including the possible occurrence of past perturbations. The primary objective of this study is to present palaeoenvironmental evidence for the existence of past disturbances in the forests of the Kisangani region (Democratic Republic of the Congo) using a pedoanthracological approach. We quantified and identified charcoal fragments from pedoanthracological excavations in the Yangambi, Yoko, Masako and Kole forest regions. Charcoal sampling was conducted in pit intervals of 10 cm, whereby pottery fragments were also registered and quantified. Floristic identifications were conducted using former protocols based on wood anatomy, which is largely preserved after charcoalification. 14 excavations were conducted and charcoal was found in most pit intervals. Specifically, 52 out of 56 sampled intervals from the Yangambi forest contained charcoal, along with 47 pit intervals from the Yoko forest reserve, 34 pit intervals from the Masako forest and 16 from the Kole forest. Highest specific anthracomasses were recorded in Yoko (167 mg charcoal per kg soil), followed by Yangambi (133 mg/kg), Masako (71,89 mg/kg) and finally Kole (42,4 mg/kg). Charcoal identifications point at a manifest presence of the family of Fabaceae (Caesalpinioideae). This family is characteristic for the tropical humid rainforest. The presence of charcoal fragments from these taxa, associated with pottery sherds on different depths within the profiles, suggests

  8. Deforestation Effects on Soil Erosion in the Lake Kivu Basin, D.R. Congo-Rwanda

    Directory of Open Access Journals (Sweden)

    Fidele Karamage

    2016-11-01

    Full Text Available Deforestation and natural grassland conversion to agricultural land use constitute a major threat to soil and water conservation. This study aimed at assessing the status of land cover and land use (LCLU in the Lake Kivu basin, and its related impacts in terms of soil erosion by water using the Universal Soil Erosion Equation (USLE model. The results indicated that the Lake Kivu basin is exposed to soil erosion risk with a mean annual rate of 30 t·ha−1, and only 33% of the total non-water area is associated with a tolerable soil loss (≤10 t·ha−1·year−1. Due to both natural factors (abundant tropical precipitation and steep slopes and anthropogenic activities without prior appropriate conservation practices, all land-use types—namely settlement, cropland, forestland, and grassland—are exposed to a severe mean erosion rate of 41 t·ha−1·year−1, 31 t·ha−1·year−1, 28 t·ha−1·year−1, and 20 t·ha−1·year−1, respectively. The cropland that occupied 74% of the non-water area in 2015 was the major contributor (75% to the total annual soil loss in the Lake Kivu basin. This study showed that conservation practices in the cropland cells would result in a mean erosion rate of 7 t·ha−1·year−1, 18 t·ha−1·year−1, and 35 t·ha−1·year−1 for terracing, strip-cropping, and contouring, respectively. The adoption of terracing would be the best conservation practice, among others, that could reduce soil erosion in cropland areas up to about 23%. The erosion risk minimization in forests and grasslands implies an increase in overstorey canopy and understorey vegetation, and control of human activities such as fires, mining, soil compaction from domestic animals grazing, and so on. Soil erosion control in settled areas suggests, among other things, the revegetation of construction sites, establishment of outlet channels, rainfall water harvesting systems, and pervious paving block with grass.

  9. National-scale estimation of gross forest aboveground carbon loss: a case study of the Democratic Republic of the Congo

    International Nuclear Information System (INIS)

    Tyukavina, A; Potapov, P V; Turubanova, S A; Hansen, M C; Stehman, S V; Baccini, A; Goetz, S J; Laporte, N T; Houghton, R A

    2013-01-01

    Recent advances in remote sensing enable the mapping and monitoring of carbon stocks without relying on extensive in situ measurements. The Democratic Republic of the Congo (DRC) is among the countries where national forest inventories (NFI) are either non-existent or out of date. Here we demonstrate a method for estimating national-scale gross forest aboveground carbon (AGC) loss and associated uncertainties using remotely sensed-derived forest cover loss and biomass carbon density data. Lidar data were used as a surrogate for NFI plot measurements to estimate carbon stocks and AGC loss based on forest type and activity data derived using time-series multispectral imagery. Specifically, DRC forest type and loss from the FACET (Forêts d’Afrique Centrale Evaluées par Télédétection) product, created using Landsat data, were related to carbon data derived from the Geoscience Laser Altimeter System (GLAS). Validation data for FACET forest area loss were created at a 30-m spatial resolution and compared to the 60-m spatial resolution FACET map. We produced two gross AGC loss estimates for the DRC for the last decade (2000–2010): a map-scale estimate (53.3 ± 9.8 Tg C yr −1 ) accounting for whole-pixel classification errors in the 60-m resolution FACET forest cover change product, and a sub-grid estimate (72.1 ± 12.7 Tg C yr −1 ) that took into account 60-m cells that experienced partial forest loss. Our sub-grid forest cover and AGC loss estimates, which included smaller-scale forest disturbances, exceed published assessments. Results raise the issue of scale in forest cover change mapping and validation, and subsequent impacts on remotely sensed carbon stock change estimation, particularly for smallholder dominated systems such as the DRC. (letter)

  10. Future Discounting in Congo Basin Hunter-Gatherers Declines with Socio-Economic Transitions.

    Directory of Open Access Journals (Sweden)

    Gul Deniz Salali

    Full Text Available Humans have a tendency to discount the future; that is we value small, short-term rewards over larger, long-term rewards. The degree of future discounting, however, changes in response to socio-ecological factors. Here, we study Mbendjele BaYaka hunter-gatherers of northern Congo and their farmer neighbours to investigate adaptations in inter-temporal preferences in humans. We argue that in immediate-return systems, where food storage is absent and egalitarianism is enforced through levelling mechanisms, future discounting is an adaptive strategy to prevent wealth accumulation and the emergence of hierarchies. This ensures food sharing and allows for survival in unpredictable environments where there is risk of an energy shortfall. On the other hand, when food storage is made possible by the emergence of agriculture or as seen in some delayed-return hunter-gatherer populations, wealth accumulation, hierarchies and lower discount rates become the adaptive strategy. Therefore, individuals in immediate-return, egalitarian societies will discount the future more than those in non-egalitarian, delayed-return societies. Consistent with the predictions we found that market integration and socio-economic transitions decrease the future discounting in Mbendjele hunter-gatherers. Our measures of socio-economic differences marked this transition in hunter-gatherers living in a logging town. The degree of future-discounting was the same between more market-integrated hunter-gatherers and their farmer neighbours.

  11. "Congo" red: out of Africa?

    Science.gov (United States)

    Steensma, D P

    2001-02-01

    Congo red is the essential histologic stain for demonstrating the presence of amyloidosis in fixed tissues. To the best of my knowledge, nothing has been written about why the stain is named "Congo." To understand the etymology and history of the Congo red histologic stain. Primary sources were consulted extensively, including 19th-century corporate documents, newspapers, legal briefs, patents, memoirs, and scientific papers. Sources were obtained from multiple university libraries and German corporate archives. To Europeans in 1885, the word Congo evoked exotic images of far-off central Africa known as The Dark Continent. The African Congo was also a political flashpoint during the Age of Colonialism. "Congo" red was introduced in Berlin in 1885 as the first of the economically lucrative direct textile dyes. A patent on Congo red was filed by the AGFA Corporation of Berlin 3 weeks after the conclusion of the well-publicized Berlin West Africa Conference. During these important diplomatic talks, German Chancellor Otto von Bismarck presided over a discussion of free trade issues in the Congo River basin. A challenge to AGFA's Congo red patent led to a precedent-setting decision in intellectual property law. The Congo red stain was named "Congo" for marketing purposes by a German textile dyestuff company in 1885, reflecting geopolitical current events of that time.

  12. Assessing tropical rainforest growth traits: Data - Model fusion in the Congo basin and beyond

    Science.gov (United States)

    Pietsch, Stephan

    2017-04-01

    Virgin forest ecosystems resemble the key reference level for natural tree growth dynamics. The mosaic cycle concept describes such dynamics as local disequilibria driven by patch level succession cycles of breakdown, regeneration, juvenescence and old growth. These cycles, however, may involve different traits of light demanding and shade tolerant species assemblies. In this work a data model fusion concept will be introduced to assess the differences in growth dynamics of the mosaic cycle of the Western Congolian Lowland Rainforest ecosystem. Field data from 34 forest patches located in an ice age forest refuge, recently pinpointed to the ground and still devoid of direct human impact up to today - resemble the data base. A 3D error assessment procedure versus BGC model simulations for the 34 patches revealed two different growth dynamics, consistent with observed growth traits of pioneer and late succession species assemblies of the Western Congolian Lowland rainforest. An application of the same procedure to Central American Pacific rainforests confirms the strength of the 3D error field data model fusion concept to Central American Pacific rainforests confirms the strength of the 3D error field data model fusion concept to assess different growth traits of the mosaic cycle of natural forest dynamics.

  13. Structure and dynamics of basin forested wetlands in North America

    International Nuclear Information System (INIS)

    Brown, S.

    1990-01-01

    Freshwater basin wetlands are found in depressions of various depths, generally in areas where precipitation exceeds evapotranspiration or where the depression intersects the water table creating groundwater seeps or springs. Forested basins are those that contain woody vegetation with the potential for reaching tree stature; they do not include woody shrub wetlands. In North America these areas are mainly in the central and eastern region. Pertinent information and reviews on the distribution, floristic composition, structure and dynamics of basin forested wetlands are summarized. The major emphasis is on freshwater wetlands, but data for saltwater wetlands mainly from Florida and tropical America are included. The external factors affecting basin wetlands or the important components of a wetlands energy signature are described as well as the distribution and floristic composition of representative basin wetlands. Sections on structural characteristics, organic matter dynamics, and nutrient cycling comprise the bulk of quantitative information. The effects of disturbances, both natural and human induced, with varying degrees of impact depending upon the intensity and on the part of the ecosystem to which the stressor is applied are evaluated. Examples of stressors in basin wetlands include water impoundment, water diversion, thermal stress from hot water, sedimentation, addition of toxic substances, addition of wastewater, oil spills, and harvesting. 86 refs., 5 figs., 11 tabs

  14. Simulations of forest mortality in Colorado River basin

    Science.gov (United States)

    Wei, L.; Xu, C.; Johnson, D. J.; Zhou, H.; McDowell, N.

    2017-12-01

    The Colorado River Basin (CRB) had experienced multiple severe forest mortality events under the recent changing climate. Such forest mortality events may have great impacts on ecosystem services and water budget of the watershed. It is hence important to estimate and predict the forest mortality in the CRB with climate change. We simulated forest mortality in the CRB with a model of plant hydraulics within the FATES (the Functionally Assembled Terrestrial Ecosystem Simulator) coupled to the DOE Earth System model (ACME: Accelerated Climate Model of Energy) at a 0.5 x 0.5 degree resolution. Moreover, we incorporated a stable carbon isotope (δ13C) module to ACME(FATE) and used it as a new predictor of forest mortality. The δ13C values of plants with C3 photosynthetic pathway (almost all trees are C3 plants) can indicate the water stress plants experiencing (the more intensive stress, the less negative δ13C value). We set a δ13C threshold in model simulation, above which forest mortality initiates. We validate the mortality simulations with field data based on Forest Inventory and Analysis (FIA) data, which were aggregated into the same spatial resolution as the model simulations. Different mortality schemes in the model (carbon starvation, hydraulic failure, and δ13C) were tested and compared. Each scheme demonstrated its strength and the plant hydraulics module provided more reliable simulations of forest mortality than the earlier ACME(FATE) version. Further testing is required for better forest mortality modelling.

  15. Organic matter sources, fluxes and greenhouse gas exchange in the Oubangui River (Congo River basin)

    Science.gov (United States)

    Bouillon, S.; Yambélé, A.; Spencer, R. G. M.; Gillikin, D. P.; Hernes, P. J.; Six, J.; Merckx, R.; Borges, A. V.

    2012-06-01

    The Oubangui is a major tributary of the Congo River, draining an area of ~500 000 km2 mainly consisting of wooded savannahs. Here, we report results of a one year long, 2-weekly sampling campaign in Bangui (Central African Republic) since March 2010 for a suite of physico-chemical and biogeochemical characteristics, including total suspended matter (TSM), bulk concentration and stable isotope composition of particulate organic carbon (POC and δ13CPOC), particulate nitrogen (PN and δ15NPN), dissolved organic carbon (DOC and δ13CDOC), dissolved inorganic carbon (DIC and δ13CDIC), dissolved greenhouse gases (CO2, CH4 and N2O), and dissolved lignin composition. δ13C signatures of both POC and DOC showed strong seasonal variations (-30.6 to -25.8‰, and -31.8 to -27.1‰, respectively), but their different timing indicates that the origins of POC and DOC may vary strongly over the hydrograph and are largely uncoupled, differing up to 6‰ in δ13C signatures. Dissolved lignin characteristics (carbon-normalised yields, cinnamyl:vanillyl phenol ratios, and vanillic acid to vanillin ratios) showed marked differences between high and low discharge conditions, consistent with major seasonal variations in the sources of dissolved organic matter. We observed a strong seasonality in pCO2, ranging between 470 ± 203 ppm for Q production may be high enough to dominate the particulate organic carbon pool, and lower pCO2 values to near equilibrium values during low discharge conditions. The total annual flux of TSM, POC, PN, DOC and DIC are 2.33 Tg yr-1, 0.14 Tg C yr-1, 0.014 Tg N yr-1, 0.70 Tg C yr-1, and 0.49 Tg C yr-1, respectively. While our TSM and POC fluxes are similar to previous estimates for the Oubangui, DOC fluxes were ~30% higher and bicarbonate fluxes were ~35% lower than previous reports. DIC represented 58% of the total annual C flux, and under the assumptions that carbonate weathering represents 25% of the DIC flux and that CO2 from respiration drives

  16. High prevalence of cannabis use among Aka foragers of the Congo Basin and its possible relationship to helminthiasis.

    Science.gov (United States)

    Roulette, Casey J; Kazanji, Mirdad; Breurec, Sébastien; Hagen, Edward H

    2016-01-01

    Little is known about cannabis use in hunter-gatherers. Therefore, we investigated cannabis use in the Aka, a population of foragers of the Congo Basin. Because cannabis contains anthelminthic compounds, and the Aka have a high prevalence of helminthiasis, we also tested the hypothesis that cannabis use might be an unconscious form of self-medication against helminths. We collected self- and peer-reports of cannabis use from all adult Aka in the Lobaye district of the Central African Republic (n = 379). Because female cannabis use was low, we restricted sample collection to men. Using an immunoassay for Δ9-tetrahydrocannabinol-11-oic acid (THCA), a urinary biomarker of recent cannabis consumption, we validated cannabis use in men currently residing in camps near a logging road (n = 62). We also collected stool samples to assay worm burden. A longitudinal reinfection study was conducted among a subsample of the male participants (n = 23) who had been treated with a commercial anthelmintic 1 year ago. The prevalence of self- and peer-reported cannabis use was 70.9% among men and 6.1% among women, for a total prevalence of 38.6%. Using a 50 ng/ml threshold for THCA, 67.7% of men used cannabis. Cannabis users were significantly younger and had less material wealth than the non-cannabis users. There were significant negative associations between THCA levels and worm burden, and reinfection with helminths 1 year after treatment with a commercial anthelmintic. The prevalence of cannabis use among adult Aka men was high when compared to most global populations. THCA levels were negatively correlated with parasite infection and reinfection, supporting the self-medication hypothesis. © 2015 Wiley Periodicals, Inc.

  17. Organic matter sources, fluxes and greenhouse gas exchange in the Oubangui River (Congo River basin

    Directory of Open Access Journals (Sweden)

    S. Bouillon

    2012-06-01

    Full Text Available The Oubangui is a major tributary of the Congo River, draining an area of ~500 000 km2 mainly consisting of wooded savannahs. Here, we report results of a one year long, 2-weekly sampling campaign in Bangui (Central African Republic since March 2010 for a suite of physico-chemical and biogeochemical characteristics, including total suspended matter (TSM, bulk concentration and stable isotope composition of particulate organic carbon (POC and δ13CPOC, particulate nitrogen (PN and δ15NPN, dissolved organic carbon (DOC and δ13CDOC, dissolved inorganic carbon (DIC and δ13CDIC, dissolved greenhouse gases (CO2, CH4 and N2O, and dissolved lignin composition. δ13C signatures of both POC and DOC showed strong seasonal variations (−30.6 to −25.8‰, and −31.8 to −27.1‰, respectively, but their different timing indicates that the origins of POC and DOC may vary strongly over the hydrograph and are largely uncoupled, differing up to 6‰ in δ13C signatures. Dissolved lignin characteristics (carbon-normalised yields, cinnamyl:vanillyl phenol ratios, and vanillic acid to vanillin ratios showed marked differences between high and low discharge conditions, consistent with major seasonal variations in the sources of dissolved organic matter. We observed a strong seasonality in pCO2, ranging between 470 ± 203 ppm for Q < 1000 m3 s−1 (n=10 to a maximum of 3750 ppm during the first stage of the rising discharge. The low POC/PN ratios, high %POC and low and variable δ13CPOC signatures during low flow conditions suggest that the majority of the POC pool during this period consists of in situ produced phytoplankton, consistent with concurrent pCO2 (partial pressure of CO2 values only slightly

  18. Forest cover dynamics of shifting cultivation in the Democratic Republic of Congo: a remote sensing-based assessment for 2000-2010

    Science.gov (United States)

    Molinario, G.; Hansen, M. C.; Potapov, P. V.

    2015-09-01

    Shifting cultivation has traditionally been practiced in the Democratic Republic of Congo by carving agricultural fields out of primary and secondary forest, resulting in the rural complex: a characteristic land cover mosaic of roads, villages, active and fallow fields and secondary forest. Forest clearing has varying impacts depending on where it occurs relative to this area: whether inside it, along its primary forest interface, or in more isolated primary forest areas. The spatial contextualization of forest cover loss is therefore necessary to understand its impacts and plan its management. We characterized forest clearing using spatial models in a Geographical Information System, applying morphological image processing to the Forets d’Afrique Central Evaluee par Teledetection product. This process allowed us to create forest fragmentation maps for 2000, 2005 and 2010, classifying previously homogenous primary forest into separate patch, edge, perforated, fragmented and core forest subtypes. Subsequently we used spatial rules to map the established rural complex separately from isolated forest perforations, tracking the growth of these areas in time. Results confirm that the expansion of the rural complex and forest perforations has high variance throughout the country, with consequent differences in local impacts on forest ecology and habitat fragmentation. Between 2000 and 2010 the rural complex grew by 10.2% (46 182 ha), increasing from 11.9% to 13.1% of the total land area (1.2% change) while perforated forest grew by 74.4% (23 856 ha), from 0.8% to 1.5%. Core forest decreased by 3.8% (54 852 ha), from 38% to 36.6% of the 2010 land area. Of particular concern is the nearly doubling of perforated forest, a land dynamic that represents greater spatial intrusion of forest clearing within core forest areas and a move away from the established rural complex.

  19. Nitrogen dynamics in subtropical fringe and basin mangrove forests inferred from stable isotopes.

    Science.gov (United States)

    Reis, Carla Roberta Gonçalves; Nardoto, Gabriela Bielefeld; Rochelle, André Luis Casarin; Vieira, Simone Aparecida; Oliveira, Rafael Silva

    2017-03-01

    Mangroves exhibit low species richness compared to other tropical forests, but great structural and functional diversity. Aiming to contribute to a better understanding of the functioning of mangrove forests, we investigated nitrogen (N) dynamics in two physiographic types of mangroves (fringe and basin forests) in southeastern Brazil. Because fringe forests are under great influence of tidal flushing we hypothesized that these forests would exhibit higher N cycling rates in sediment and higher N losses to the atmosphere compared to basin forests. We quantified net N mineralization and nitrification rates in sediment and natural abundance of N stable isotopes (δ 15 N) in the sediment-plant-litter system. The fringe forest exhibited higher net N mineralization rates and δ 15 N in the sediment-plant-litter system, but net nitrification rates were similar to those of the basin forest. The results of the present study suggest that fringe forests exhibit higher N availability and N cycling in sediment compared to basin forests.

  20. Use of forest products by the local people of the Salonga National Park in the Congo

    Directory of Open Access Journals (Sweden)

    Jose Mbenga Ibesoa

    2009-01-01

    Full Text Available This article attempted to define a compromise making it possible the satisfaction of the material needs of the populations living within the National park of Salonga while ensuring the conservation of long-term forest resources. The management of the forests requires deepened knowledge of the resources and the participation of the local communities, which are the better, informed on of the forest resources. The implementing of a policy on sustainable forest management would be possible by a better integration and participation of the local populations. A survey was carried out in four villages of the National park of Salonga. The results of the investigation show clearly a positive attitude of the rural populations with regard to the forest resources. The diversity of the needs for the population corresponds to the choice of the products and services of the forest. Overall, the potential of the park’s forests is superior in comparison with the needs of the population. The exploitation of the forest products is vast and is included in the category of a system of an economy of collection.

  1. “But the forest does know it...” Persistence of omusitu in the BaNande culture and thought (Democratic Republic of Congo)

    OpenAIRE

    Francesco Remotti

    2016-01-01

    The BaNande, farmers of the hills of the North Kivu (Democratic Republic of the Congo), call themselves proudly abakondi, the young and strong men who cut down the trees, who destroy the forest. Almost their entire culture is based on the principle of the “cut” (eritwa), as well as their social and political organization is due to the historical achievement of their territory wrested from the forest. Even the erotic activity is designed with the typical categories of abakondi. But the traditi...

  2. Dynamic behaviour of natural oil droplets through the water column in deep-water environment: the case of the Lower Congo Basin

    Science.gov (United States)

    Jatiault, R.; Dhont, D.; Loncke, L.; Durrieu De Madron, X.; Dubucq, D.; Channelliere, C.; Bourrin, F.

    2017-12-01

    Key words: Hydrocarbon seepage, Oil Slick, Lower Congo Basin, Underwater deflection, Deep-water Pockmark, Ascent speedThe space-borne imagery provides a significant means to locate active oil seeps and to estimate the expelled volume in the marine environment. The analysis of numerous overlapping satellite images revealed an abundant volume of 4400 m3 of oil naturally reaching the sea surface per year, expelled from more than a hundred seep sites through the Lower Congo Basin. The active seepage area is located in the distal compressional province of the basin where salt napes and squeezed diapirs. The integration of current data was used to link accurately sea surface manifestations of natural oil leakages with active fluid flow features on the seafloor. A mooring with ADCPs (Acoustic Doppler Current Profilers) distributed throughout the water column provided an efficient calibration tool to evaluate the horizontal deflection of oil droplets. Using a Eulerian propagation model that considered a range of probable ascent speeds, we estimated the oil migration pathways through the water column using two different approaches. The first approach consisted in simulating the backwards trajectory of oil droplets using sea surface oil slicks locations and concomitant current measurements. The second method analyzed the spatial spreading of the surfacing signatures of natural oil slicks based on 21 years of satellite observations. The location of the surfacing points of oil droplets at the sea surface is restricted to a circle of 2.5 km radius around the release point at the seafloor. Both approaches provided a range of ascent speeds of oil droplets between 3 to 8 cm.s-1. The low deflection values validate the near-vertical links between the average surfacing area of oil slicks at the sea surface with specific seafloor disturbances (i.e. pockmarks or mounds) known to expel fluids.

  3. Water Storage Changes using Floodplain Bathymetry from InSAR and satellite altimetry in the Congo River Basin

    Science.gov (United States)

    Yuan, T.; Lee, H.; Jung, H. C.; Beighley, E.; Alsdorf, D. E.

    2016-12-01

    Extensive wetlands and swamps expand along the Congo River and its tributaries. These wetlands store water and attenuate flood wave during high water season. Substantial dissolved and solid substances are also transported with the water flux, influencing geochemical environment and biogeochemistry processes both in the wetlands and the river. To understand the role of the wetlands in partitioning the surface water and the accompanied material movement, water storage change is one of the most fundamental observations. The water flow through the wetlands is complex, affected by topography, vegetation resistance, and hydraulic variations. Interferometric Synthetic Aperture Radar (InSAR) has been successfully used to map relative water level changes in the vegetated wetlands with high spatial resolution. By examining interferograms generated from ALOS PALSAR along the middle reach of the Congo River floodplain, we found greater water level changes near the Congo mainstem. Integrated analysis of InSAR and Envisat altimetry data has shown that proximal floodplain with higher water level change has lower elevation during dry season. This indicates that the spatial variation of water level change in the Congo floodplain is mostly controlled by floodplain bathymetry. A method based on water level and bathymetry model is proposed to estimate water storage change. The bathymetry model is composed of (1) elevation at the intersection of the floodplain and the river and (2) floodplain bathymetry slope. We first constructed the floodplain bathymetry by selecting an Envisat altimetry profile during low water season to estimate elevation at the intersection of the floodplain and the river. Floodplain bathymetry slope was estimated using InSAR measurements. It is expected that our new method can estimate water storage change with higher temporal resolution corresponding to altimeter's repeat cycle. In addition, given the multi-decadal archive of satellite altimetry measurements

  4. 76 FR 78234 - Medicine Bow-Routt National Forests and Thunder Basin National Grassland, Campbell County, WY...

    Science.gov (United States)

    2011-12-16

    ... DEPARTMENT OF AGRICULTURE Forest Service Medicine Bow-Routt National Forests and Thunder Basin... Supervisor, Medicine Bow-Routt National Forests and Thunder Basin National Grassland, 2250 East Richards.... Responsible Official Richard Cooksey, Deputy Forest Supervisor, Medicine Bow-Routt National Forests and...

  5. Late Holocene swampy forest of Loango Bay (Congo). Sedimentary environments and organic matter deposition

    Science.gov (United States)

    Malounguila-Nganga, Dieudonné; Giresse, Pierre; Boussafir, Mohammed; Miyouna, Timothée

    2017-10-01

    This region, comprised between the Kouilou estuary and Pointe-Noire, is characterised by a very specific morphological setting. On the continental side, the coastal sector is dominated by cliffs of sand over 100 m high, referred to as the Série des Cirques, whereas, on the ocean side, very active erosion is presently taking place which has resulted in a retreat of the shoreline of more than 100 m over the last hundred years. New 14C datings and different analyses of organic matter and clay minerals (X-Ray data) were performed in order to reconstruct the geological and ecological evolution of the area during the Late Holocene and replace it in the palaeoclimatic scheme deduced from previous regional studies. From 7 to 6000 yr cal BP, the accumulation of important beach barriers by the oceanic drift allowed the definition of a narrow swamp depression several tens of kilometres long. A dense ombrophile and hydromorphic forest, in spite of being very close to the oceanic coast, remained sheltered from any brackish influence and fed accumulations of peat and organic muds. The emersive trend of 3000-2000 yr BP, i.e. the passage from a vast forest swamp with a water body several metres deep to a wet zone with some emersions, is expressed by a large colluvial accumulation. High primary production is not clearly attested in this wet area. High HI values would indicate rather long-lasting conservation in a swampy environment, the lowest values indicating alternating episodes of emersion and immersion. In such peatlands, OM preservation is favoured by an anoxic environment and rapid burial. The δ 13C values of older peats dated ca. 7000 yr cal BP are -28 to -26‰, typical of a C3 origin. Thus, the ca. -16‰ value indicates the greatest opening of the cover, suggesting a forest-savanna mosaic ca. 2500 yr cal BP. At Kivesso, several proxies suggest a wetter trend towards 500 yr cal BP. An ultimate drier trend is observed during the last two centuries, which has been

  6. Paleoenvironments, δ13C and δ18O signatures in the Neoproterozoic carbonates of the Comba Basin, Republic of Congo: Implications for regional correlations and Marinoan event

    Science.gov (United States)

    Préat, Alain; Delpomdor, Franck; Ackouala Mfere, Anna Perla; Callec, Yannick

    2018-01-01

    The Ediacaran Schisto-Calcaire Group is a ∼1300 m-thick succession belonging to the West Congo Supergroup in Central Africa. In the Comba Basin, it consists of three carbonate-dominated units defined as formations (SCI to SCIII) that are unconformably overlain by clastic deposits (Mpioka Group) interpreted as a molassic formation associated with the Panafrican Orogen. The underlying Upper Tillite and Cap Carbonate (SCIa) units, considered as markers of the Snowball Earth event were studied in three sections. We investigated the carbonates of the Schisto-Calcaire Group by defining new microfacies (MF1-MF7) and we performed C and O isotopic analyses in order to constraint the depositional and diagenetic events directly after the Marinoan interval. Stratigraphic variations of the stable isotopes are important in the series with lighter δ18O values (>1.5‰) than those of the Neoproterozoic ocean in the SCIc unit. According to regional stratigraphy a temperature effect can be dismissed and a freshwater surface layer is the origin of such negative δ18O values in this unit. The negative δ13C anomaly (-3.5‰ on average) of the Cap Carbonate is similarly to the δ18O values (-6.4‰ on average) in the range of the marine domain during postglacial sea level rise. The sample suite as a whole (SCII and SCIII formations) displays heavier δ18O and δ13C than those of the lower part (SCI unit) of the Schisto-Calcaire Group. The comparison with the Lower Congo (Democratic Republic of Congo) and Nyanga (Gabon) basins shows that the meteoric flushing in SCIc unit of the Schisto-Calcaire Group was regional and not local, and could be derived from a climatic evolution. Although an overall overprint is present, our isotopic relationships argue against overall diagenetic resetting of primary compositions and suggest that with careful examination combined with detailed petrographic analysis general depositional and diagenetic controls can be discerned in oxygen and carbon

  7. Forest changes since Euro-American settlement and ecosystem restoration in the Lake Tahoe Basin, USA

    Science.gov (United States)

    Alan H. Taylor

    2007-01-01

    Pre Euro-American settlement forest structure and fire regimes for Jeffrey pine-white fir, red fir-western white pine, and lodgepole pine forests were quantified using stumps from trees cut in the 19th century to establish a baseline reference for ecosystem management in the Lake Tahoe Basin. Contemporary forests varied in different ways compared...

  8. Intestinal Helminths of Wild Bonobos in Forest-Savanna Mosaic: Risk Assessment of Cross-Species Transmission with Local People in the Democratic Republic of the Congo.

    Science.gov (United States)

    Narat, Victor; Guillot, Jacques; Pennec, Flora; Lafosse, Sophie; Grüner, Anne Charlotte; Simmen, Bruno; Bokika Ngawolo, Jean Christophe; Krief, Sabrina

    2015-12-01

    Phylogenetic and geographic proximities between humans and apes pose a risk of zoonotic transmission of pathogens. Bonobos (Pan paniscus) of the Bolobo Territory, Democratic Republic of the Congo, live in a fragmented forest-savanna mosaic setting, a marginal habitat for this species used to living in dense forests. Human activities in the forest have increased the risk of contacts between humans and bonobos. Over 21 months (September 2010-October 2013), we monitored intestinal parasites in bonobo (n = 273) and in human (n = 79) fecal samples to acquire data on bonobo parasitology and to assess the risk of intestinal helminth transmission between these hosts. Coproscopy, DNA amplification, and sequencing of stored dried feces and larvae were performed to identify helminths. Little difference was observed in intestinal parasites of bonobos in this dryer habitat compared to those living in dense forests. Although Strongylids, Enterobius sp., and Capillaria sp. were found in both humans and bonobos, the species were different between the hosts according to egg size or molecular data. Thus, no evidence of helminth transmission between humans and bonobos was found. However, because humans and this threatened species share the same habitat, it is essential to continue to monitor this risk.

  9. “But the forest does know it...” Persistence of omusitu in the BaNande culture and thought (Democratic Republic of Congo

    Directory of Open Access Journals (Sweden)

    Francesco Remotti

    2016-12-01

    Full Text Available The BaNande, farmers of the hills of the North Kivu (Democratic Republic of the Congo, call themselves proudly abakondi, the young and strong men who cut down the trees, who destroy the forest. Almost their entire culture is based on the principle of the “cut” (eritwa, as well as their social and political organization is due to the historical achievement of their territory wrested from the forest. Even the erotic activity is designed with the typical categories of abakondi. But the traditional culture of the BaNande was not geared only to this sense of conquest of the forest. The author of this article tries to show how the forest (omusitu would be made to survive in different ways. First, not all of the forest was destroyed. Indeed islands of forest remain here and there, such as supplies of food, timber, medicines, as memory of what had been destroyed, and as headquarters of the forest spirits. Second, whenever a chief died, he was buried on his hill not underground, but imprisoned by the trees of the forest planted all around his body. These tree tombs, real historical monuments of vegetable nature, are called by the BaNande amahero and are designed as “small forest” (singular akasitu. Finally it was diffused in the nande culture the awareness that the destruction of the forest doesn’t happen with impunity. The pride of abakondi is replaced by the recognition of omusitu (forest as autonomous world, which demands to be at least partially preserved, both physically in the territory, both as an entity with even “consciousness”. Once, the BaNande thought of not being able to break free from this consciousness, and this ecological anxiety emerged especially in the most significant moments of the reproduction of their culture, i.e. when in the olusumba (their rite of initiation in the forest they had to form their new men. But this conscience belongs to the past: on the hills of the Bunande the “spirits of the forest” have

  10. Modelling basin-wide variations in Amazon forest photosynthesis

    Science.gov (United States)

    Mercado, Lina; Lloyd, Jon; Domingues, Tomas; Fyllas, Nikolaos; Patino, Sandra; Dolman, Han; Sitch, Stephen

    2010-05-01

    type parameter values are assigned and assumed invariant with environmental condition but also ii) these models use leaf N as a factor that limit photosynthesis. Instead, since leaf P may also limit photosynthesis of the tropical forest (Reich et al. 2009), we use a more specific description of photosynthetic capacity across the basin based on the model evaluation done in Mercado et al. (2009) in which canopy photosynthetic capacity is related to foliar P but also using the relationships derived between canopy photosynthesis and leaf nutrients (N and P) from measurements in tropical trees (Domingues et al.In review). A study of this kind can inform the global vegetation/climate community as to the need for variability in key model parameters in order to accurately simulate carbon fluxes across the Amazon basin. Baker, T. R., et al. 2004. Increasing biomass in Amazonian forest plots. Philosophical Transactions of the Royal Society of London Series B-Biological Sciences 359 (1443):353-365. Phillips, O. L. et al. 2004. Pattern and process in Amazon tree turnover, 1976-2001. Philosophical Transactions of the Royal Society of London Series B-Biological Sciences 359 (1443):381-407. Malhi, Y. et al. 2004. The above-ground coarse wood productivity of 104 Neotropical forest plots. Global Change Biology 10 (5):563-591. Mercado, L.M. et al. 2009. Impact of changes in diffuse radiation on the global land carbon sink. Nature 458 (7241), 1014. Cox, P. M. et al. 1998. A canopy conductance and photosynthesis model for use in a GCM land surface scheme. Journal of Hydrology 213 (1-4):79-9 Sitch, S. et al. 2003. Evaluation of ecosystem dynamics, plant geography and terrestrial carbon cycling in the LPJ dynamic global vegetation model. Global Change Biology 9 (2):161-185. Reich B. R. et al. 2009. Leaf phosphorus influences the photosynhtesis-nitrogen relation: a cross-biome analysis of 314 species. Oecologia, doi 10.1007/s00442-009-1291-3. Domingues, T. et al. In review. Co-limitation of

  11. Classification of very high resolution satellite remote sensing data in a pilot phase of the forest cover classification of the Democratic Republic of Congo, Forêts d'Afrique Central Evaluées par Télédetection (FACET) product

    Science.gov (United States)

    Singa Monga Lowengo, C.

    2012-12-01

    The Observatoire Satellital des Forêts d'Afrique Centrale (OSFAC) based in Kinshasa, serves as the focal point of the GOFC-GOLD network for Central Africa. OSFAC's long term objective is building regional capacity to use remotely sensed data to map forest cover and forest cover change across Central Africa. OSFAC archives and disseminates satellite data, offers training in geospatial data applications in coordination with the University of Kinshasa, and provides technical support to CARPE partners. Forêts d'Afrique Centrale Évaluées par Télédétection (FACET) is an OSFAC initiative that implements the UMD/SDSU methodology at the national level and quantitatively evaluates the spatiotemporal dynamics of forest cover in Central Africa. The multi-temporal series of FACET data is a useful contribution to many projects, such as biodiversity monitoring, climate modeling, conservation, natural resource management, land use planning, agriculture and REDD+. I am working as Remote Sensing and GIS Officer in various projects of OSFAC. My activities include forest cover and lands dynamics monitoring in Congo Basin. I am familiar with the use of digital mapping software, GIS and RS (Arc GIS, ENVI and PCI Geomatica etc.), classification and spatial Analysis of satellite images, 3D modeling, etc. I started as an intern at OSFAC, Assistant Trainer (Professional Training) and Consultant than permanent employee since October 2009. To assist in the OSFAC activities regarding the monitoring of forest cover and the CARPE program in the context of natural resources management, I participated in the development of the FACET Atlas (Republic of Congo). I received data from Matt Hansen (map.img), WRI and Brazzaville (shapefiles). With all these data I draw maps of the ROC Atlas and statistics of forest cover and forest loss. We organize field work on land to collect data to validate the FACET product. Therefore, to assess forest cover in the region of Kwamouth and Kahuzi-Maiko Biega

  12. The Role of Forests in Regulating the River Flow Regime of Large Basins of the World

    Science.gov (United States)

    Salazar, J. F.; Villegas, J. C.; Mercado-Bettin, D. A.; Rodríguez, E.

    2017-12-01

    Many natural and social phenomena depend on river flow regimes that are being altered by global change. Understanding the mechanisms behind such alterations is crucial for predicting river flow regimes in a changing environment. Here we explore potential linkages between the presence of forests and the capacity of river basins for regulating river flows. Regulation is defined here as the capacity of river basins to attenuate the amplitude of the river flow regime, that is to reduce the difference between high and low flows. We first use scaling theory to show how scaling properties of observed river flows can be used to classify river basins as regulated or unregulated. This parsimonious classification is based on a physical interpretation of the scaling properties (particularly the scaling exponents) that is novel (most previous studies have focused on the interpretation of the scaling exponents for floods only), and widely-applicable to different basins (the only assumption is that river flows in a given river basin exhibit scaling properties through well-known power laws). Then we show how this scaling framework can be used to explore global-change-induced temporal variations in the regulation capacity of river basins. Finally, we propose a conceptual hypothesis (the "Forest reservoir concept") to explain how large-scale forests can exert important effects on the long-term water balance partitioning and regulation capacity of large basins of the world. Our quantitative results are based on data analysis (river flows and land cover features) from 22 large basins of the world, with emphasis in the Amazon river and its main tributaries. Collectively, our findings support the hypothesis that forest cover enhances the capacity of large river basins to maintain relatively high mean river flows, as well as to regulate (ameliorate) extreme river flows. Advancing towards this quantitative understanding of the relation between forest cover and river flow regimes is

  13. Multi-stakeholder design of forest governance and accountability arrangements in Equator province, Democratic Republic of Congo

    NARCIS (Netherlands)

    Klaver, D.C.

    2009-01-01

    Good forest governance is an increasingly important topic for stakeholders in many different settings around the world. Two of the best-known international initiatives to improve forest governance are the regional Forest Law Enforcement and Governance (FLEG) ministerial processes supported by the

  14. A refined model of sedimentary rock cover in the southeastern part of the Congo basin from GOCE gravity and vertical gravity gradient observations

    Science.gov (United States)

    Martinec, Zdeněk; Fullea, Javier

    2015-03-01

    We aim to interpret the vertical gravity and vertical gravity gradient of the GOCE-GRACE combined gravity model over the southeastern part of the Congo basin to refine the published model of sedimentary rock cover. We use the GOCO03S gravity model and evaluate its spherical harmonic representation at or near the Earth's surface. In this case, the gradiometry signals are enhanced as compared to the original measured GOCE gradients at satellite height and better emphasize the spatial pattern of sedimentary geology. To avoid aliasing, the omission error of the modelled gravity induced by the sedimentary rocks is adjusted to that of the GOCO03S gravity model. The mass-density Green's functions derived for the a priori structure of the sediments show a slightly greater sensitivity to the GOCO03S vertical gravity gradient than to the vertical gravity. Hence, the refinement of the sedimentary model is carried out for the vertical gravity gradient over the basin, such that a few anomalous values of the GOCO03S-derived vertical gravity gradient are adjusted by refining the model. We apply the 5-parameter Helmert's transformation, defined by 2 translations, 1 rotation and 2 scale parameters that are searched for by the steepest descent method. The refined sedimentary model is only slightly changed with respect to the original map, but it significantly improves the fit of the vertical gravity and vertical gravity gradient over the basin. However, there are still spatial features in the gravity and gradiometric data that remain unfitted by the refined model. These may be due to lateral density variation that is not contained in the model, a density contrast at the Moho discontinuity, lithospheric density stratifications or mantle convection. In a second step, the refined sedimentary model is used to find the vertical density stratification of sedimentary rocks. Although the gravity data can be interpreted by a constant sedimentary density, such a model does not correspond to

  15. Effects of drainage-basin geomorphology on insectivorous bird abundance in temperate forests.

    Science.gov (United States)

    Iwata, Tomoya; Urabe, Jotaro; Mitsuhashi, Hiromune

    2010-10-01

    Interfaces between terrestrial and stream ecosystems often enhance species diversity and population abundance of ecological communities beyond levels that would be expected separately from both the ecosystems. Nevertheless, no study has examined how stream configuration within a watershed influences the population of terrestrial predators at the drainage-basin scale. We examined the habitat and abundance relationships of forest insectivorous birds in eight drainage basins in a cool temperate forest of Japan during spring and summer. Each basin has different drainage-basin geomorphology, such as the density and frequency of stream channels. In spring, when terrestrial arthropod prey biomass is limited, insectivorous birds aggregated in habitats closer to streams, where emerging aquatic prey was abundant. Nevertheless, birds ceased to aggregate around streams in summer because terrestrial prey became plentiful. Watershed-scale analyses showed that drainage basins with longer stream channels per unit area sustained higher densities of insectivorous birds. Moreover, such effects of streams on birds continued from spring through summer, even though birds dispersed out of riparian areas in the summer. Although our data are from only a single year, our findings imply that physical modifications of stream channels may reduce populations of forest birds; thus, they emphasize the importance of landscape-based management approaches that consider both stream and forest ecosystems for watershed biodiversity conservation. © 2010 Society for Conservation Biology.

  16. Le rayon de déforestation autour de la ville de Lubumbashi (Haut-Katanga, R.D. Congo: synthèse

    Directory of Open Access Journals (Sweden)

    Useni Sikuzani, Y.

    2017-01-01

    Full Text Available The Deforestation Radius Around Lubumbashi City (Upper Katanga, DR Congo: Synthesis. The Miombo woodland is a type of vegetation widely distributed in Zambezian Africa where it provides timber and non-timber forest products to millions of inhabitants. In Lubumbashi, the causes of its degradation, supported by rapid population growth, are mainly: (i agricultural development, (ii charcoal production, (iii urban expansion, and (iv mining activities. We present a meta-analysis of the studies that have defined the deforestation radius around Lubumbashi. This radius, used both to express the area (circular area, intensity and the magnitude (distance to the city of deforestation, was determined through in situ charcoal production and remote sensing. Although the city's ecological footprint is illustrated, estimates of the resulting deforested area do not appear to be consistent because of the variability of methodological protocols within and between approaches. While studies focusing on charcoal production suggest complete Miombo woodland suppression around the city, those based on remote sensing mention the persistence of Miombo patches relatively close to the city and sometimes confuse the different levels of Miombo degradation. These observations prevent the development of an appropriate policy for the conservation and sustainable use of the concerned ecosystem.

  17. Challenges to governing sustainable forest food and landscapes: Irvingia spp. from southern Cameroon

    NARCIS (Netherlands)

    Ingram, V.J.; Ewane, Marcos; Ndumbe, L.N.; Awono, A.

    2017-01-01

    Across the Congo Basin, bush mango (Irvingia spp.) nuts have been harvested from forest landscapes for consumption, sold as a foodstuff and for medicine for centuries. Data on this trade however are sparse. A value chain approach was used to gather information on stakeholders in the chain from the

  18. Vulnerability, forest-related sectors and climate change adaptation : the case of Cameroon

    NARCIS (Netherlands)

    Sonwa, D.J.; Somorin, O.A.; Jum, C.; Bele, M.Y.; Nkem, J.N.

    2012-01-01

    In Cameroon and elsewhere in the Congo Basin, the majority of rural households and a large proportion of urban households depend on plant and animal products from the forests to meet their nutritional, energy, cultural and medicinal needs. This paper explores the likely impacts of climate-induced

  19. Hydrologic regimes of forested, mountainous, headwater basins in New Hampshire, North Carolina, Oregon, and Puerto Rico

    Science.gov (United States)

    David A. Post; Julia A. Jones

    2001-01-01

    This study characterized the hydrologic regimes at four forested, mountainous long-term ecological research (LTER) sites: H.J. Andrews (Oregon), Coweeta (North Carolina), Hubbard Brook (New Hampshire), and Luquillo (Puerto Rico). Over 600 basinyears of daily streadow records were examined from 18 basins that have not experienced human disturbances since at least the...

  20. Widespread decline of Congo rainforest greenness in the past decade.

    Science.gov (United States)

    Zhou, Liming; Tian, Yuhong; Myneni, Ranga B; Ciais, Philippe; Saatchi, Sassan; Liu, Yi Y; Piao, Shilong; Chen, Haishan; Vermote, Eric F; Song, Conghe; Hwang, Taehee

    2014-05-01

    Tropical forests are global epicentres of biodiversity and important modulators of climate change, and are mainly constrained by rainfall patterns. The severe short-term droughts that occurred recently in Amazonia have drawn attention to the vulnerability of tropical forests to climatic disturbances. The central African rainforests, the second-largest on Earth, have experienced a long-term drying trend whose impacts on vegetation dynamics remain mostly unknown because in situ observations are very limited. The Congolese forest, with its drier conditions and higher percentage of semi-evergreen trees, may be more tolerant to short-term rainfall reduction than are wetter tropical forests, but for a long-term drought there may be critical thresholds of water availability below which higher-biomass, closed-canopy forests transition to more open, lower-biomass forests. Here we present observational evidence for a widespread decline in forest greenness over the past decade based on analyses of satellite data (optical, thermal, microwave and gravity) from several independent sensors over the Congo basin. This decline in vegetation greenness, particularly in the northern Congolese forest, is generally consistent with decreases in rainfall, terrestrial water storage, water content in aboveground woody and leaf biomass, and the canopy backscatter anomaly caused by changes in structure and moisture in upper forest layers. It is also consistent with increases in photosynthetically active radiation and land surface temperature. These multiple lines of evidence indicate that this large-scale vegetation browning, or loss of photosynthetic capacity, may be partially attributable to the long-term drying trend. Our results suggest that a continued gradual decline of photosynthetic capacity and moisture content driven by the persistent drying trend could alter the composition and structure of the Congolese forest to favour the spread of drought-tolerant species.

  1. The Bonobo Pan paniscus (Mammalia: Primates: Hominidae nesting patterns and forest canopy layers in the Lake Tumba forests and Salonga National Park, Democratic Republic of Congo

    Directory of Open Access Journals (Sweden)

    Bila-Isia Inogwabini

    2015-10-01

    Full Text Available The description and differentiation of habitat types is a major concern in ecology.  This study examined relationships between Bonobo Pan paniscus nesting patterns and forest structure in the Lake Tumba Swampy Forests. Data on presence of fresh Bonobo nests, canopy cover, canopy structure, tree densities and tree basal areas were collected systematically along 134 transects at 400m and 800m intervals, and the leaf-covered area (LCA was calculated for each of seven forest types. I observed a significant correlation between bonobo nests and mixed mature forest/closed understory forest type (r=-0.730, df = 21, p <0.05, but not mixed mature forest/open understory, old secondary forest and young secondary forest.  Basal areas of non-nesting trees along transects did not differ significantly from those in sites where bonobos nested.  Higher LCA (55% and 55% occurred in nesting sites when compared with non-nesting sites (39% and 42% at elevations 4–8 m and 8–16 m above the soil.  There was greater leaf cover in the understorey at sites where bonobos did not nest, while there was greater leaf cover in the mid-storey at sites where bonobos did nest.  

  2. Preliminary ecological study of plant species of Lokame Natural Forest (Nord Ubangi Province, Democratic Republic of the Congo): A special emphasis on Non-timber Forest Products

    OpenAIRE

    Koto-te-Nyiwa Ngbolua,

    2017-01-01

    A preliminary ecological study with a special emphasis on Non-timber forest products (NTFPs) was conducted between 2014 and 2015 on both anks of Lokame River in Lokame forest. The results showed that the Lokame natural forest has a very rich and diversified in NTFPs. Data collected over a total area of 2 ha identified 20 families and 25 different plant species producing NTFPs and 914 individuals, of which 39% are food, 38% for different uses, 14% for aphrodisiacs and 9% as medicinal. A compar...

  3. REDD+ projects in the Democratic Republic of Congo: impacts on future emissions, income and biodiversity

    Science.gov (United States)

    Mosnier, Aline; Bocqueho, Geraldine; Mant, Rebecca; Obersteiner, Michael; Havlik, Petr; Kapos, Val; Fritz, Steffen; Botrill, Leo

    2014-05-01

    The Democratic Republic of Congo (DRC) encompasses a large rainforest area which has been rather preserved up to now. However, pressure on the forests is increasing with high population growth, transition toward political stability and the abundance of minerals in the country. REDD+ is a developing mechanism under the UNFCCC that aims to support developing countries that want to make efforts to reduce their emissions from deforestation and forest degradation. The REDD+ strategy in DRC combines an independent national fund and independent REDD+ projects at the local level that are at the initial stage of implementation. The objective of this paper is to assess i) emissions reduction due to the implementation of the REDD+ pilot projects taking into account potential leakage and ii) potential co-benefits of REDD+ pilot projects in terms of biodiversity and rural income by 2030. We use the land use economic model CongoBIOM adapted from GLOBIOM which represents land-based activities and land use changes at a 50x50km resolution level. It includes domestic and international demand for agricultural products, fuel wood and minerals which are the main deforestation drivers in the Congo Basin region. Finally, we run a sensitivity analysis on emissions from land use change according to three different above and below ground living biomass estimates: downscaled FAO, NASA and WHRC.

  4. Firewood harvest from forests of the Murray-Darling Basin, Australia. Part 1: Long-term, sustainable supply available from native forests

    International Nuclear Information System (INIS)

    West, P.W.; Cawsey, E.M.; Stol, J.; Freudenberger, D.

    2008-01-01

    The Murray-Darling Basin is a 1 million km 2 agricultural region of south-eastern Australia, although 29% of it retains native forests. Some are mallee eucalypt types, whilst the 'principal' types are dominated mainly by other eucalypt species. One-third of the 6-7 million oven-dry tonne of firewood burnt annually in Australia is obtained from these forests, principally through collection of coarse woody debris. There are fears that removal of this debris may prejudice the floral and faunal biodiversity of the Basin. The present work considers what silvicultural management practices will allow the long-term maintenance of the native forests of the Basin and their continued contribution to its biodiversity. It then estimates that the maximum, long-term, annual, sustainable yield of firewood which could be harvested, by collection of coarse woody debris, from principal forest types of the Basin would be 10 million oven-dry tonne yr -1 . An alternative, harvest of firewood from live trees by thinning the principal forests and clear-felling mallee forests, would be able to supply 2.3 million tonne yr -1 sustainably. Whilst coarse woody debris harvests could supply far more than the present demand for firewood from the Basin, they would lead to substantial reductions of the debris remaining in the forests; this may be detrimental to biodiversity maintenance. Live tree harvest does not lead to this problem, but would barely be able to supply existing firewood demand

  5. Exploring forest infrastructures equipment through multivariate analysis: complementarities, gaps and overlaps in the Mediterranean basin

    Directory of Open Access Journals (Sweden)

    Sofia Bajocco

    2013-12-01

    Full Text Available The countries of the Mediterranean basin face several challenges regarding the sustainability of forest ecosystems and the delivery of crucial goods and services that they provide in a context of rapid global changes. Advancing scientific knowledge and foresting innovation is essential to ensure the sustainable management of Mediterranean forests and maximize the potential role of their unique goods and services in building a knowledge-based bioeconomy in the region. In this context, the European project FORESTERRA ("Enhancing FOrest RESearch in the MediTERRAnean through improved coordination and integration” aims at reinforcing the scientific cooperation on Mediterranean forests through an ambitious transnational framework in order to reduce the existing research fragmentation and maximize the effectiveness of forest research activities. Within the FORESTERRA project framework, this work analyzed the infrastructures equipment of the Mediterranean countries belonging to the project Consortium. According to the European Commission, research infrastructures are facilities, resources and services that are used by the scientific communities to conduct research and foster innovation. To the best of our knowledge, the equipment and availability of infrastructures, in terms of experimental sites, research facilities and databases, have only rarely been explored. The aim of this paper was hence to identify complementarities, gaps and overlaps among the different forest research institutes in order to create a scientific network, optimize the resources and trigger collaborations.

  6. Nutrient status and plant growth effects of forest soils in the Basin of Mexico

    Science.gov (United States)

    Mark E. Fenn; V.M. Perea-Estrada; L.I. de Bauer; M. Pérez-Suárez; D.R. Parker; V.M. Cetina-Alcalá

    2006-01-01

    The nutrient status of forest soils in the Mexico City Air Basin was evaluated by observing plant growth responses to fertilization with N, P or both nutrients combined. P deficiency was the most frequent condition for soil from two high pollution sites and N deficiency was greatest at a low N deposition site. Concentrations of Pb and Ni, and to a lesser extent Zn and...

  7. Nutrient status and plant growth effects of forest soils in the Basin of Mexico

    International Nuclear Information System (INIS)

    Fenn, M.E.; Perea-Estrada, V.M.; Bauer, L.I. de; Perez-Suarez, M.; Parker, D.R.; Cetina-Alcala, V.M.

    2006-01-01

    The nutrient status of forest soils in the Mexico City Air Basin was evaluated by observing plant growth responses to fertilization with N, P or both nutrients combined. P deficiency was the most frequent condition for soil from two high pollution sites and N deficiency was greatest at a low N deposition site. Concentrations of Pb and Ni, and to a lesser extent Zn and Co, were higher at the high pollution sites. However, positive plant growth responses to P and sometimes to N, and results of wheat root elongation bioassays, suggest that heavy metal concentrations were not directly phytotoxic. Further studies are needed to determine if heavy metal toxicity to mycorrhizal symbionts of eucalyptus (Eucalyptus camaldulensis Dehnh.) from high pollution sites may explain the P deficiency and stunted growth. P deficiency is expected to limit the capacity for biotic N retention in N saturated forested watersheds in the Basin of Mexico dominated by Andisols. - Plant response to N deposition may be limited by P limitation in forests growing on Andisol soils in the Basin of Mexico

  8. Nutrient status and plant growth effects of forest soils in the Basin of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Fenn, M.E. [USDA Forest Service, Pacific Southwest Research Station, Forest Fire Laboratory, 4955 Canyon Crest Dr., Riverside, CA 92507 (United States)]. E-mail: mfenn@fs.fed.us; Perea-Estrada, V.M. [Instituto de Recursos Naturales, Colegio de Postgraduados, CP 56230 Montecillo (Mexico); Bauer, L.I. de [Instituto de Recursos Naturales, Colegio de Postgraduados, CP 56230 Montecillo (Mexico)]. E-mail: libauer@colpos.mx; Perez-Suarez, M. [Instituto de Recursos Naturales, Colegio de Postgraduados, CP 56230 Montecillo (Mexico); Parker, D.R. [Department of Environmental Sciences, University of California, Riverside, CA 92521 (United States)]. E-mail: david.parker@ucr.edu; Cetina-Alcala, V.M. [Instituto de Recursos Naturales, Colegio de Postgraduados, CP 56230 Montecillo (Mexico)

    2006-03-15

    The nutrient status of forest soils in the Mexico City Air Basin was evaluated by observing plant growth responses to fertilization with N, P or both nutrients combined. P deficiency was the most frequent condition for soil from two high pollution sites and N deficiency was greatest at a low N deposition site. Concentrations of Pb and Ni, and to a lesser extent Zn and Co, were higher at the high pollution sites. However, positive plant growth responses to P and sometimes to N, and results of wheat root elongation bioassays, suggest that heavy metal concentrations were not directly phytotoxic. Further studies are needed to determine if heavy metal toxicity to mycorrhizal symbionts of eucalyptus (Eucalyptus camaldulensis Dehnh.) from high pollution sites may explain the P deficiency and stunted growth. P deficiency is expected to limit the capacity for biotic N retention in N saturated forested watersheds in the Basin of Mexico dominated by Andisols. - Plant response to N deposition may be limited by P limitation in forests growing on Andisol soils in the Basin of Mexico.

  9. Parameterisation of Biome BGC to assess forest ecosystems in Africa

    Science.gov (United States)

    Gautam, Sishir; Pietsch, Stephan A.

    2010-05-01

    African forest ecosystems are an important environmental and economic resource. Several studies show that tropical forests are critical to society as economic, environmental and societal resources. Tropical forests are carbon dense and thus play a key role in climate change mitigation. Unfortunately, the response of tropical forests to environmental change is largely unknown owing to insufficient spatially extensive observations. Developing regions like Africa where records of forest management for long periods are unavailable the process-based ecosystem simulation model - BIOME BGC could be a suitable tool to explain forest ecosystem dynamics. This ecosystem simulation model uses descriptive input parameters to establish the physiology, biochemistry, structure, and allocation patterns within vegetation functional types, or biomes. Undocumented parameters for larger-resolution simulations are currently the major limitations to regional modelling in African forest ecosystems. This study was conducted to document input parameters for BIOME-BGC for major natural tropical forests in the Congo basin. Based on available literature and field measurements updated values for turnover and mortality, allometry, carbon to nitrogen ratios, allocation of plant material to labile, cellulose, and lignin pools, tree morphology and other relevant factors were assigned. Daily climate input data for the model applications were generated using the statistical weather generator MarkSim. The forest was inventoried at various sites and soil samples of corresponding stands across Gabon were collected. Carbon and nitrogen in the collected soil samples were determined from soil analysis. The observed tree volume, soil carbon and soil nitrogen were then compared with the simulated model outputs to evaluate the model performance. Furthermore, the simulation using Congo Basin specific parameters and generalised BIOME BGC parameters for tropical evergreen broadleaved tree species were also

  10. Variation of Annual ET Determined from Water Budgets Across Rural Southeastern Basins Differing in Forest Types

    Science.gov (United States)

    Younger, S. E.; Jackson, C. R.

    2017-12-01

    In the Southeastern United States, evapotranspiration (ET) typically accounts for 60-70% of precipitation. Watershed and plot scale experiments show that evergreen forests have higher ET rates than hardwood forests and pastures. However, some plot experiments indicate that certain hardwood species have higher ET than paired evergreens. The complexity of factors influencing ET in mixed land cover watersheds makes identifying the relative influences difficult. Previous watershed scale studies have relied on regression to understand the influences or low flow analysis to indicate growing season differences among watersheds. Existing studies in the southeast investigating ET rates for watersheds with multiple forest cover types have failed to identify a significant forest type effect, but these studies acknowledge small sample sizes. Trends of decreasing streamflow have been recognized in the region and are generally attributed to five key factors, 1.) influences from multiple droughts, 2.) changes in distribution of precipitation, 3.) reforestation of agricultural land, 4.) increasing consumptive uses, or 5.) a combination of these and other factors. This study attempts to address the influence of forest type on long term average annual streamflow and on stream low flows. Long term annual ET rates were calculated as ET = P-Q for 46 USGS gaged basins with daily data for the 1982 - 2014 water years, >40% forest cover, and no large reservoirs. Land cover data was regressed against ET to describe the relationship between each of the forest types in the National Land Cover Database. Regression analysis indicates evergreen land cover has a positive relationship with ET while deciduous and total forest have a negative relationship with ET. Low flow analysis indicates low flows tend to be lower in watersheds with more evergreen cover, and that low flows increase with increasing deciduous cover, although these relationships are noisy. This work suggests considering forest

  11. Spatially explicit estimation of aboveground boreal forest biomass in the Yukon River Basin, Alaska

    Science.gov (United States)

    Ji, Lei; Wylie, Bruce K.; Brown, Dana R. N.; Peterson, Birgit E.; Alexander, Heather D.; Mack, Michelle C.; Rover, Jennifer R.; Waldrop, Mark P.; McFarland, Jack W.; Chen, Xuexia; Pastick, Neal J.

    2015-01-01

    Quantification of aboveground biomass (AGB) in Alaska’s boreal forest is essential to the accurate evaluation of terrestrial carbon stocks and dynamics in northern high-latitude ecosystems. Our goal was to map AGB at 30 m resolution for the boreal forest in the Yukon River Basin of Alaska using Landsat data and ground measurements. We acquired Landsat images to generate a 3-year (2008–2010) composite of top-of-atmosphere reflectance for six bands as well as the brightness temperature (BT). We constructed a multiple regression model using field-observed AGB and Landsat-derived reflectance, BT, and vegetation indices. A basin-wide boreal forest AGB map at 30 m resolution was generated by applying the regression model to the Landsat composite. The fivefold cross-validation with field measurements had a mean absolute error (MAE) of 25.7 Mg ha−1 (relative MAE 47.5%) and a mean bias error (MBE) of 4.3 Mg ha−1(relative MBE 7.9%). The boreal forest AGB product was compared with lidar-based vegetation height data; the comparison indicated that there was a significant correlation between the two data sets.

  12. Dependence of hydropower energy generation on forests in the Amazon Basin at local and regional scales.

    Science.gov (United States)

    Stickler, Claudia M; Coe, Michael T; Costa, Marcos H; Nepstad, Daniel C; McGrath, David G; Dias, Livia C P; Rodrigues, Hermann O; Soares-Filho, Britaldo S

    2013-06-04

    Tropical rainforest regions have large hydropower generation potential that figures prominently in many nations' energy growth strategies. Feasibility studies of hydropower plants typically ignore the effect of future deforestation or assume that deforestation will have a positive effect on river discharge and energy generation resulting from declines in evapotranspiration (ET) associated with forest conversion. Forest loss can also reduce river discharge, however, by inhibiting rainfall. We used land use, hydrological, and climate models to examine the local "direct" effects (through changes in ET within the watershed) and the potential regional "indirect" effects (through changes in rainfall) of deforestation on river discharge and energy generation potential for the Belo Monte energy complex, one of the world's largest hydropower plants that is currently under construction on the Xingu River in the eastern Amazon. In the absence of indirect effects of deforestation, simulated deforestation of 20% and 40% within the Xingu River basin increased discharge by 4-8% and 10-12%, with similar increases in energy generation. When indirect effects were considered, deforestation of the Amazon region inhibited rainfall within the Xingu Basin, counterbalancing declines in ET and decreasing discharge by 6-36%. Under business-as-usual projections of forest loss for 2050 (40%), simulated power generation declined to only 25% of maximum plant output and 60% of the industry's own projections. Like other energy sources, hydropower plants present large social and environmental costs. Their reliability as energy sources, however, must take into account their dependence on forests.

  13. Hydrological Responses to Changes in the Rainfall Regime are Less Pronounced in Forested Basins: an Analysis of Southern Brazil, 1975-2010

    Science.gov (United States)

    Chagas, V. B. P.; Chaffe, P. L. B.

    2017-12-01

    It is unknown to what extent the hydrological responses to changes in the rainfall regime vary across forested and non-forested landscapes. Southern Brazil is approximately 570000 km² and was naturally covered mostly by tropical and subtropical forests. In the last century, a large proportion of forests were replaced by agricultural activities. The rainfall regime has also changed substantially in the last decades. The annual rainfall, number and magnitude of extreme events, and number of non-rainy days have increased in most of the area. In this study, we investigated the changes in the regime of 142 streamflow gauges and 674 rainfall gauges in Southern Brazil, from 1975 to 2010. The changes in the regime were analyzed for forested basins (i.e., with more than 50% forest coverage) and non-forested basins (i.e., with less than 20% forest coverage). The area of the river basins ranged from 100 to 60000 km². We analyzed a total of six signatures that represent the regime, including annual averages, seasonality, floods, and droughts. The statistical trends of the signatures were calculated using the Mann-Kendall test and the Sen's slope. The results showed that the majority of basins with opposing signal trends for mean annual streamflow and rainfall are non-forested basins (i.e., basins with higher anthropogenic impacts). Forested basins had a lower correlation between trends in the streamflow and rainfall trends for the seasonality and the average duration of drought events. There was a lower variability in the annual maximum 1-day streamflow trends in the forested basins. Additionally, despite a decrease in the 31-day rainfall minima and an increase in the seasonality, in forested basins the 7-day streamflow minima increases were substantially larger than in non-forested basins. In summary, the forested basins were less responsive to the changes in the precipitation 1-day maxima, seasonality, number of dry days, and 31-day minima.

  14. Forest fire occurrence increases the distribution of a scarce forest type in the Mediterranean Basin

    Science.gov (United States)

    Arnan, Xavier; Quevedo, Lídia; Rodrigo, Anselm

    2013-01-01

    Here we report how fire recurrence increases the distribution of a scarce forest type in NE Spain that is dominated by the resprouter tree species Arbutus unedo. We used a combination of GIS and field surveys to determine the effect of fire and pre-fire vegetation on the appearance of A. unedo forests. In the field, we also analyzed the factors that promote fire and lead to the appearance of A. unedo forests. Our results reveal an increased occurrence of A. unedo forests in NE Spain in recent years; this phenomenon was strongly related to fire recurrence and the vegetation type present prior to fire. Most Pinus halepensis forests that burned more than once gave rise to A. unedo forests. Our results indicate that these conversions were related to a reduction in pine density coupled with increases in the density and size of A. unedo trees due to recurrent fires. Given that fires are increasing in number and magnitude in the Mediterranean, we predict a major change in landscape structure and composition at the regional scale.

  15. Widespread Amazon forest tree mortality from a single cross-basin squall line event

    Science.gov (United States)

    Negrón-Juárez, Robinson I.; Chambers, Jeffrey Q.; Guimaraes, Giuliano; Zeng, Hongcheng; Raupp, Carlos F. M.; Marra, Daniel M.; Ribeiro, Gabriel H. P. M.; Saatchi, Sassan S.; Nelson, Bruce W.; Higuchi, Niro

    2010-08-01

    Climate change is expected to increase the intensity of extreme precipitation events in Amazonia that in turn might produce more forest blowdowns associated with convective storms. Yet quantitative tree mortality associated with convective storms has never been reported across Amazonia, representing an important additional source of carbon to the atmosphere. Here we demonstrate that a single squall line (aligned cluster of convective storm cells) propagating across Amazonia in January, 2005, caused widespread forest tree mortality and may have contributed to the elevated mortality observed that year. Forest plot data demonstrated that the same year represented the second highest mortality rate over a 15-year annual monitoring interval. Over the Manaus region, disturbed forest patches generated by the squall followed a power-law distribution (scaling exponent α = 1.48) and produced a mortality of 0.3-0.5 million trees, equivalent to 30% of the observed annual deforestation reported in 2005 over the same area. Basin-wide, potential tree mortality from this one event was estimated at 542 ± 121 million trees, equivalent to 23% of the mean annual biomass accumulation estimated for these forests. Our results highlight the vulnerability of Amazon trees to wind-driven mortality associated with convective storms. Storm intensity is expected to increase with a warming climate, which would result in additional tree mortality and carbon release to the atmosphere, with the potential to further warm the climate system.

  16. Recent shift from forest to savanna burning in the Amazon Basin observed by satellite

    International Nuclear Information System (INIS)

    Ten Hoeve, J E; Jacobson, M Z; Remer, L A; Correia, A L

    2012-01-01

    The numbers of fires detected on forest, savanna and transition lands during the 2002–10 biomass burning seasons in Amazonia are shown using fire count data and co-located land cover classifications from the Moderate Resolution Imaging Spectroradiometer (MODIS). The ratio of forest fires to savanna fires has varied substantially over the study period, with a maximum ratio of 0.65:1 in 2005 and a minimum ratio of 0.27:1 in 2009, with the four lowest years occurring in 2007–10. The burning during the droughts of 2007 and 2010 is attributed to a higher number of savanna fires relative to the drought of 2005. A decrease in the regional mean single scattering albedo of biomass burning aerosols, consistent with the shift from forest to savanna burning, is also shown. During the severe drought of 2010, forest fire detections were lower in many areas compared with 2005, even though the drought was more severe in 2010. This result suggests that improved fire management practices, including stricter burning regulations as well as lower deforestation burning, may have reduced forest fires in 2010 relative to 2005 in some areas of the Amazon Basin. (letter)

  17. Effects of disturbance and climate change on ecosystem performance in the Yukon River Basin boreal forest

    Science.gov (United States)

    Wylie, Bruce K.; Rigge, Matthew B.; Brisco, Brian; Mrnaghan, Kevin; Rover, Jennifer R.; Long, Jordan

    2014-01-01

    A warming climate influences boreal forest productivity, dynamics, and disturbance regimes. We used ecosystem models and 250 m satellite Normalized Difference Vegetation Index (NDVI) data averaged over the growing season (GSN) to model current, and estimate future, ecosystem performance. We modeled Expected Ecosystem Performance (EEP), or anticipated productivity, in undisturbed stands over the 2000–2008 period from a variety of abiotic data sources, using a rule-based piecewise regression tree. The EEP model was applied to a future climate ensemble A1B projection to quantify expected changes to mature boreal forest performance. Ecosystem Performance Anomalies (EPA), were identified as the residuals of the EEP and GSN relationship and represent performance departures from expected performance conditions. These performance data were used to monitor successional events following fire. Results suggested that maximum EPA occurs 30–40 years following fire, and deciduous stands generally have higher EPA than coniferous stands. Mean undisturbed EEP is projected to increase 5.6% by 2040 and 8.7% by 2070, suggesting an increased deciduous component in boreal forests. Our results contribute to the understanding of boreal forest successional dynamics and its response to climate change. This information enables informed decisions to prepare for, and adapt to, climate change in the Yukon River Basin forest.

  18. Basin-Wide Amazon Forest Tree Mortality From a Large 2005 Storm

    Science.gov (United States)

    Negron Juarez, R. I.; Chambers, J. Q.; Guimaraes, G.; Zeng, H.; Raupp, C.; Marra, D. M.; Ribeiro, G.; Saatchi, S. S.; Higuchi, N.

    2010-12-01

    Blowdowns are a recurrent characteristic of Amazon forests and are produced, among others, by squall lines. Squall lines are aligned clusters (typical length of 1000 km, width of 200 km) of deep convective cells that produce heavy rainfall during the dry season and significant rainfall during the wet season. These squall lines (accompanied by intense downbursts from convective cells) have been associated with large blowdowns characterized by uprooted, snapped trees, and trees being dragged down by other falling trees. Most squall lines in Amazonia form along the northeastern coast of South America as sea breeze-induced instability lines and propagate inside the continent. They occur frequently (~4 times per month), and can reach the central and even extreme western parts of Amazonia. Squall lines can also be generated inside the Amazon and propagate toward the equator. In January 2005 a squall line propagated from south to north across the entire Amazon basin producing widespread forest tree mortality and contributed to the elevated mortality observed that year. Over the Manaus region (3.4 x104 km2), disturbed forest patches generated by the squall produced a mortality of 0.3-0.5 million trees, equivalent to 30% of the observed annual deforestation reported in 2005 over the same area. The elevated mortality observed in the Central Amazon in 2005 is unlikely to be related to the 2005 Amazon drought since drought did not affect Central or Eastern Amazonia. Assuming a similar rate of forest mortality across the basin, the squall line could have potentially produced tree mortality estimated at 542 ± 121 million trees, equivalent to 23% of the mean annual biomass accumulation estimated for these forests. Our results highlight the vulnerability of Amazon trees to wind-driven mortality associated with convective storms. This vulnerability is likely to increase in a warming climate with models projecting an increase in storm intensity.

  19. Dependence of hydropower energy generation on forests in the Amazon Basin at local and regional scales

    Science.gov (United States)

    Stickler, Claudia M.; Coe, Michael T.; Costa, Marcos H.; Nepstad, Daniel C.; McGrath, David G.; Dias, Livia C. P.; Rodrigues, Hermann O.; Soares-Filho, Britaldo S.

    2013-01-01

    Tropical rainforest regions have large hydropower generation potential that figures prominently in many nations’ energy growth strategies. Feasibility studies of hydropower plants typically ignore the effect of future deforestation or assume that deforestation will have a positive effect on river discharge and energy generation resulting from declines in evapotranspiration (ET) associated with forest conversion. Forest loss can also reduce river discharge, however, by inhibiting rainfall. We used land use, hydrological, and climate models to examine the local “direct” effects (through changes in ET within the watershed) and the potential regional “indirect” effects (through changes in rainfall) of deforestation on river discharge and energy generation potential for the Belo Monte energy complex, one of the world’s largest hydropower plants that is currently under construction on the Xingu River in the eastern Amazon. In the absence of indirect effects of deforestation, simulated deforestation of 20% and 40% within the Xingu River basin increased discharge by 4–8% and 10–12%, with similar increases in energy generation. When indirect effects were considered, deforestation of the Amazon region inhibited rainfall within the Xingu Basin, counterbalancing declines in ET and decreasing discharge by 6–36%. Under business-as-usual projections of forest loss for 2050 (40%), simulated power generation declined to only 25% of maximum plant output and 60% of the industry’s own projections. Like other energy sources, hydropower plants present large social and environmental costs. Their reliability as energy sources, however, must take into account their dependence on forests. PMID:23671098

  20. Thermal characteristics and bacterial diversity of forest soil in the Haean basin of Korea.

    Science.gov (United States)

    Kim, Heejung; Lee, Jin-Yong; Lee, Kang-Kun

    2014-01-01

    To predict biotic responses to disturbances in forest environments, it is important to examine both the thermophysical properties of forest soils and the diversity of microorganisms that these soils contain. To predict the effects of climate change on forests, in particular, it is essential to understand the interactions between the soil surface, the air, and the biological diversity in the soil. In this study, the temperature and thermal properties of forest soil at three depths at a site in the Haean basin of Korea were measured over a period of four months. Metagenomic analyses were also carried out to ascertain the diversity of microorganisms inhabiting the soil. The thermal diffusivity of the soil at the study site was 5.9 × 10(-8) m(2) · s(-1). The heat flow through the soil resulted from the cooling and heating processes acting on the surface layers of the soils. The heat productivity in the soil varied through time. The phylum Proteobacteria predominated at all three soil depths, with members of Proteobacteria forming a substantial fraction (25.64 to 39.29%). The diversity and richness of microorganisms in the soil were both highest at the deepest depth, 90 cm, where the soil temperature fluctuation was the minimum.

  1. Thermal Characteristics and Bacterial Diversity of Forest Soil in the Haean Basin of Korea

    Directory of Open Access Journals (Sweden)

    Heejung Kim

    2014-01-01

    Full Text Available To predict biotic responses to disturbances in forest environments, it is important to examine both the thermophysical properties of forest soils and the diversity of microorganisms that these soils contain. To predict the effects of climate change on forests, in particular, it is essential to understand the interactions between the soil surface, the air, and the biological diversity in the soil. In this study, the temperature and thermal properties of forest soil at three depths at a site in the Haean basin of Korea were measured over a period of four months. Metagenomic analyses were also carried out to ascertain the diversity of microorganisms inhabiting the soil. The thermal diffusivity of the soil at the study site was 5.9 × 10−8 m2·s−1. The heat flow through the soil resulted from the cooling and heating processes acting on the surface layers of the soils. The heat productivity in the soil varied through time. The phylum Proteobacteria predominated at all three soil depths, with members of Proteobacteria forming a substantial fraction (25.64 to 39.29%. The diversity and richness of microorganisms in the soil were both highest at the deepest depth, 90 cm, where the soil temperature fluctuation was the minimum.

  2. Reconciling certification and intact forest landscape conservation.

    Science.gov (United States)

    Kleinschroth, Fritz; Garcia, Claude; Ghazoul, Jaboury

    2018-05-29

    In 2014, the Forest Stewardship Council (FSC) added a new criterion to its principles that requires protection of intact forest landscapes (IFLs). An IFL is an extensive area of forest that lacks roads and other signs of human activity as detected through remote sensing. In the Congo basin, our analysis of road networks in formally approved concessionary logging areas revealed greater loss of IFL in certified than in noncertified concessions. In areas of informal (i.e., nonregulated) extraction, road networks are known to be less detectable by remote sensing. Under the current definition of IFL, companies certified under FSC standards are likely to be penalized relative to the noncertified as well as the informal logging sector on account of their planned road networks, despite an otherwise better standard of forest management. This could ultimately undermine certification and its wider adoption, with implications for the future of sustainable forest management.

  3. Spatial analysis from remotely sensed observations of Congo basin of East African high Land to drain water using gravity for sustainable management of low laying Chad basin of Central Africa

    OpenAIRE

    B. Modu; B. Herbert

    2014-01-01

    The Chad basin which covers an area of about 2.4 million kilometer square is one of the largest drainage basins in Africa in the centre of Lake Chad .This basin was formed as a result of rifting and drifting episode, as such it has no outlet to the oceans or seas. It contains large area of desert from the north to the west. The basin covers in part seven countries such as Chad, Nigeria, Central African Republic, Cameroun, Niger, Sudan and Algeria. It is named Chad basin because 43.9%...

  4. Aerosol emissions from forest and grassland burnings in the southern amazon basin and central Brazil

    Science.gov (United States)

    Leslie, Alistair C. D.

    1981-03-01

    Forest and grassland clearing by means of prescribed fires in tropical areas of the world may be responsible for large inputs of fine particulates to the global atmosphere besides being a major source of trace gases. The major continents on which extensive biomass burning takes place are Africa and South America. Such agricultural practices of burning have been employed throughout man's existence, but the importance and significance of such burning relative to anthropogenic industrial emissions to the atmosphere has not until extremely recently been seriously studied. In August-September 1979 project "Brushfire 1979" took place based in Brasília, Brazil. The Air Quality Division of the National Center for Atmospheric Research made ground level and aircraft measurements of trace gases (e.g. CO 2, CO, CH 4, N 2O, H 2, CH 3Cl, COS, NO, NO 2, O 3) and Florida State University sampled ground level aerosol emissions from grass and forest burnings. Aerosols were sampled using plastic 7-stage single orifice cascade impactors and FSU type linear and circular "streakers". Long term sampling was made of regional background for total particulates (8 μmad). Short term sampling within grass or forest fires was made using impactors incorporated into portable kits containing 4 miniature 12-18 V dc Brailsford pumps and a disposable dry cell power pack. Sampling times of 5-15 min were found optimal under these conditions. Grass fires were sampled in the savannah area northeast of Brasília and forest fires in the state of Mato Grosso on the southern edge of the dryland forest of the Amazon basin. Residual ash samples were collected. All of the samples were analyzed at Florida State University using PIXE for 15-20 elements including Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Pb and Sr. Computer reduction of the X-ray spectra was made using the "HEXB" program. One of the prominent features found was the large flux of small particles (<2.0 μm) from both fire

  5. Impacts of forest changes on hydrology: a case study of large watersheds in the upper reach of Yangtze River Basin

    Science.gov (United States)

    Cui, X.; Liu, S.; Wei, X.

    2012-05-01

    Quantifying the effects of forest changes on hydrology in large watersheds is important for designing forest or land management and adaptation strategies for watershed ecosystem sustainability. Minjiang River watershed located in the upper reach of the Yangtze River Basin plays a strategic role in environmental protection and economic and social wellbeing for both the watershed and the entire Yangtze Basin. The watershed lies in the transition zone from Sichuan Basin to Qinghai-Tibet Plateau with a size of 24 000 km2. Due to its strategic significance, severe historic deforestation and high sensitivity to climate change, the watershed has long been one of the highest priority watersheds in China for scientific research and resource management. The purpose of this review paper is to provide a state-of-the-art summary on what we have learned from several recently-completed research programs (one of them known as "973 of the China National Major Fundamental Science" with funding of 3.5 million USD in 2002 to 2008). This summary paper focused on how land cover or forest change affected hydrology at both forest stand and watershed scales in this large watershed. Inclusion of two different spatial scales is useful because the results from a small spatial scale (e.g. forest stand level) can help interpret the findings at a large spatial scale. Our review suggests that historic forest harvesting or land cover change has caused significant water increase due to reduction of forest canopy interception and evapotranspiration caused by removal of forest vegetation at both spatial scales. The impact magnitudes caused by forest harvesting indicate that the hydrological effects of forest or land cover changes can be as important as those caused by climate change, while the opposite impact directions suggest their offsetting effects on water yields in the Minjiang River watershed. In addition, different types of forests have different magnitudes of ET with old-growth natural

  6. East and central farming and forest region and Atlantic basin diversified farming region: LRRs N and S

    Science.gov (United States)

    Brad D. Lee; John M. Kabrick

    2017-01-01

    The central, unglaciated US east of the Great Plains to the Atlantic coast corresponds to the area covered by LRR N (East and Central Farming and Forest Region) and S (Atlantic Basin Diversified Farming Region). These regions roughly correspond to the Interior Highlands, Interior Plains, Appalachian Highlands, and the Northern Coastal Plains.

  7. Basin-wide variations in Amazon forest structure and function are mediated by both soils and climate

    Science.gov (United States)

    Quesada, C. A.; Phillips, O. L.; Schwarz, M.; Czimczik, C. I.; Baker, T. R.; Patiño, S.; Fyllas, N. M.; Hodnett, M. G.; Herrera, R.; Almeida, S.; Alvarez Dávila, E.; Arneth, A.; Arroyo, L.; Chao, K. J.; Dezzeo, N.; Erwin, T.; di Fiore, A.; Higuchi, N.; Honorio Coronado, E.; Jimenez, E. M.; Killeen, T.; Lezama, A. T.; Lloyd, G.; López-González, G.; Luizão, F. J.; Malhi, Y.; Monteagudo, A.; Neill, D. A.; Núñez Vargas, P.; Paiva, R.; Peacock, J.; Peñuela, M. C.; Peña Cruz, A.; Pitman, N.; Priante Filho, N.; Prieto, A.; Ramírez, H.; Rudas, A.; Salomão, R.; Santos, A. J. B.; Schmerler, J.; Silva, N.; Silveira, M.; Vásquez, R.; Vieira, I.; Terborgh, J.; Lloyd, J.

    2012-06-01

    Forest structure and dynamics vary across the Amazon Basin in an east-west gradient coincident with variations in soil fertility and geology. This has resulted in the hypothesis that soil fertility may play an important role in explaining Basin-wide variations in forest biomass, growth and stem turnover rates. Soil samples were collected in a total of 59 different forest plots across the Amazon Basin and analysed for exchangeable cations, carbon, nitrogen and pH, with several phosphorus fractions of likely different plant availability also quantified. Physical properties were additionally examined and an index of soil physical quality developed. Bivariate relationships of soil and climatic properties with above-ground wood productivity, stand-level tree turnover rates, above-ground wood biomass and wood density were first examined with multivariate regression models then applied. Both forms of analysis were undertaken with and without considerations regarding the underlying spatial structure of the dataset. Despite the presence of autocorrelated spatial structures complicating many analyses, forest structure and dynamics were found to be strongly and quantitatively related to edaphic as well as climatic conditions. Basin-wide differences in stand-level turnover rates are mostly influenced by soil physical properties with variations in rates of coarse wood production mostly related to soil phosphorus status. Total soil P was a better predictor of wood production rates than any of the fractionated organic- or inorganic-P pools. This suggests that it is not only the immediately available P forms, but probably the entire soil phosphorus pool that is interacting with forest growth on longer timescales. A role for soil potassium in modulating Amazon forest dynamics through its effects on stand-level wood density was also detected. Taking this into account, otherwise enigmatic variations in stand-level biomass across the Basin were then accounted for through the

  8. How to improve fertility of African soils? Leguminous fallows (Cameroon), addition of farmyard manure and mineral fertilizer (Kenya), organic residues management and introduction of N2 fixing species in forest plantations (Congo).

    Science.gov (United States)

    Koutika, Lydie-Stella; Mareschal, Louis; Mouanda, Cadeau; Epron, Daniel

    2014-05-01

    Most of African soils are inherently infertile and poor in nutrients mainly nitrogen and phosphorus. Several practices are used to improve soil fertility, increase productivity and ensure their sustainability. Soil fertility in the leguminous fallows was evaluated through particulate organic matter (POM), the more active part of soil organic matter (SOM) in Cameroon. The combination of mineral and organic (manure) fertilizers increased microbial P biomass allowing the release of P along the plant growing period in the Kenyan soils. Organic residues management and introduction of nitrogen fixing species (Acacia) were used to improve soil fertility and sustain forest productivity on the coastal plains of Congo. SOM fractionation was made under Pueraria, Mucuna fallows and natural regrowth mainly Chromolaena and under 3 forest plantation treatments installed in previous savanna: 1) no input, 2) normal input, and 3) double input of organic residues. Microbial P biomass and sequential P fractionation were evaluated in high and low P fixing soils. N, C, available P and pH were determined on soil sampled in acacia (100A), eucalypt (100E) and mixed-species (50A:50E) stands. N and P were determined in aboveground litters and in leaves, bark and wood of trees. The two leguminous fallows increased N content in POM fractions i.e., N >1% for Pueraria and Mucuna against Nplantations increased the soil N concentration under the mixed-species stand (N>0.06%) compared to under the pure eucalypt stand (N1% in the mixed stand and CEucalyptus stand).

  9. Steady-state critical loads of acidity for forest soils in the Georgia Basin, British Columbia

    Directory of Open Access Journals (Sweden)

    Shaun A. WATMOUGH

    2010-08-01

    Full Text Available There has been growing interest in acid rain research in western Canada where sulphur (S and nitrogen (N emissions are expected to increase during the next two decades. One region of concern is southern British Columbia, specifically the Georgia Basin, where emissions are expected to increase owing to the expansion of industry and urban centres (Vancouver and Victoria. In the current study, weathering rates and critical loads of acidity (S and N for forest soils were estimated at nineteen sites located within the Georgia Basin. A base cation to aluminium ratio of 10 was selected as the critical chemical criterion associated with ecosystem damage. The majority of the sites (58% had low base cation weathering rates (≤50 meq m–2 y–1 based on the PROFILE model. Accordingly, mean critical load for the study sites, estimated using the steady-state mass balance model, ranged between 129–168 meq m–2 y–1. Annual average total (wet and dry S and N deposition during the period 2005–2006 (estimated by the Community Multiscale Air Quality model, exceeded critical load at five–nine of the study sites (mean exceedance = 32–46 meq m–2 y–1. The high-elevation (>1000 m study sites had shallow, acid sensitive, soils with low weathering rates; however, critical loads were predominantly exceeded at sites close to Vancouver under higher modelled deposition loads. The extent of exceedance is similar to other industrial regions in western and eastern Canada.

  10. Human exposure to metals due to consumption of fish from an artificial lake basin close to an active mining area in Katanga (D.R. Congo)

    International Nuclear Information System (INIS)

    Squadrone, S.; Burioli, E.; Monaco, G.; Koya, M.K.; Prearo, M.; Gennero, S.; Dominici, A.; Abete, M.C.

    2016-01-01

    The concentrations of 14 essential and nonessential trace elements were determined in fish from Lake Tshangalele, Katanga province, Democratic Republic of Congo. This province has been a place of intensive mining activities for centuries, which have increased in recent years, due to the use of metals such as copper and cobalt for the industries of fast-growing countries. Lake Tshangalele, which receives effluents from metallurgical and mining plants in Likasi, is home to several fish species that are an important part of the diet of the local population, and, therefore, it constitutes a relevant site for documenting the human exposure to metals as a result of a fish diet. The highest concentrations (median levels, dry weight) of cobalt (7.25 mg kg"− "1), copper (88.1 mg kg"− "1), iron (197.5 mg kg"− "1), manganese (65.35 mg kg"− "1), zinc (122.9 mg kg"− "1) and aluminum (135.4 mg kg"− "1) were found in fish collected closest to the copper mining plant, with decreasing concentrations along the lake, up to the dam. In the most contaminated fish samples, values of up to 270.1 mg kg"− "1 for Al, 173.1 mg kg"− "1 for Cu, 220.9 mg kg"− "1 for Zn, 211.0 mg kg"− "1 for Mn, 324.2 mg kg"− "1 for Fe, 15.1 mg kg"− "1 for Co, 4.2 mg kg"− "1 for Cr, 1.6 mg kg"− "1 for Cd, 1.9 mg kg"− "1 for Pb, and 1.8 mg kg"− "1 for Ni were found. Metal contamination from mining activity resulted in being of great concern because of potential health risks to the local inhabitants due to the consumption of heavily contaminated fish. Capsule: High levels of metals, especially cobalt, aluminum, iron, manganese, zinc and cadmium were found in fish from Tshangalele water system. - Highlights: • Metal contamination from mining activity is of great concern for human exposure. • We analyzed metal content in fish from Lake Tshangalele (Katanga Copperbelt). • Fish consumption largely contributes to intake of Co and other metals. • In some samples, Co, Cu, Mn, Al

  11. Human exposure to metals due to consumption of fish from an artificial lake basin close to an active mining area in Katanga (D.R. Congo)

    Energy Technology Data Exchange (ETDEWEB)

    Squadrone, S., E-mail: stefania.squadrone@izsto.it [Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d' Aosta, via Bologna 148, 10154 Torino (Italy); Burioli, E.; Monaco, G. [Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d' Aosta, via Bologna 148, 10154 Torino (Italy); Koya, M.K. [Institut Supérieur d' Etudes Agronomiques (ISEA) de Kaseya/Kongolo (Congo, The Democratic Republic of the); Prearo, M.; Gennero, S. [Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d' Aosta, via Bologna 148, 10154 Torino (Italy); Dominici, A. [Independent Veterinarian Researcher, Turin (Italy); Abete, M.C. [Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d' Aosta, via Bologna 148, 10154 Torino (Italy)

    2016-10-15

    The concentrations of 14 essential and nonessential trace elements were determined in fish from Lake Tshangalele, Katanga province, Democratic Republic of Congo. This province has been a place of intensive mining activities for centuries, which have increased in recent years, due to the use of metals such as copper and cobalt for the industries of fast-growing countries. Lake Tshangalele, which receives effluents from metallurgical and mining plants in Likasi, is home to several fish species that are an important part of the diet of the local population, and, therefore, it constitutes a relevant site for documenting the human exposure to metals as a result of a fish diet. The highest concentrations (median levels, dry weight) of cobalt (7.25 mg kg{sup −} {sup 1}), copper (88.1 mg kg{sup −} {sup 1}), iron (197.5 mg kg{sup −} {sup 1}), manganese (65.35 mg kg{sup −} {sup 1}), zinc (122.9 mg kg{sup −} {sup 1}) and aluminum (135.4 mg kg{sup −} {sup 1}) were found in fish collected closest to the copper mining plant, with decreasing concentrations along the lake, up to the dam. In the most contaminated fish samples, values of up to 270.1 mg kg{sup −} {sup 1} for Al, 173.1 mg kg{sup −} {sup 1} for Cu, 220.9 mg kg{sup −} {sup 1} for Zn, 211.0 mg kg{sup −} {sup 1} for Mn, 324.2 mg kg{sup −} {sup 1} for Fe, 15.1 mg kg{sup −} {sup 1} for Co, 4.2 mg kg{sup −} {sup 1} for Cr, 1.6 mg kg{sup −} {sup 1} for Cd, 1.9 mg kg{sup −} {sup 1} for Pb, and 1.8 mg kg{sup −} {sup 1} for Ni were found. Metal contamination from mining activity resulted in being of great concern because of potential health risks to the local inhabitants due to the consumption of heavily contaminated fish. Capsule: High levels of metals, especially cobalt, aluminum, iron, manganese, zinc and cadmium were found in fish from Tshangalele water system. - Highlights: • Metal contamination from mining activity is of great concern for human exposure. • We analyzed metal content in

  12. FLORISTIC AND STRUCTURAL CHARACTERIZATION OF GALLERY FOREST FRAGMENTS OF UPPER ARAGUAIA RIVER BASIN

    Directory of Open Access Journals (Sweden)

    Christian Dias Cabacinha

    2014-06-01

    Full Text Available http://dx.doi.org/10.5902/1980509814575The forests of upper Araguaia river basin are daily exposed to degradation agents due to intense agriculture practices. Twenty two fragments (of 10 until 169 ha were surveyed according to point-centered quarter method to characterize vegetation structure and to create a database to forest restoration. One hundred and nine (109 species, belonging to 78 genus and 42 families, were sampled where 73.4% revealed zoochorous dispersal pattern, and 69.7% were classified to initial sucessional category. Shannon index and Pielou equability index were 3.86 nats. ind-1 and 0.82, respectively. Density and total basal area estimated were 1,351 trees.ha-1 and 19.28 m2.ha-1. The areas showed lower richness, Shannon and Pielou heterogeneity indices, lower basal area, and high number of species of intermediate stage of ecological sucession and colonization of cerrado and cerradão species in disturbed areas, altering the original landscape. Such situation, added to the importance of those areas for the biodiversity conservation and ecological services (mainly relative to the water, demands protection actions and management that use the great regenerative potential of the area, given by the existence of a great number of initial secondary species and the prevalence of zoochoric species.

  13. Field abundance and nest structure of the ant Anoplolepis tenella associated with the African root and tuber scale in the Congo Basin

    OpenAIRE

    Fotso Kuate, A.; Tindo, M.; Hanna, R.; Kenne, M.; Goergen, G.

    2006-01-01

    Anoplolepis tenella is a ground-dwelling ant of the tropical forest zone of Central Africa. It is associated with the African root and tuber scale (ARTS), Stictococcus vayssierei Richard, an emerging cassava pest in the zone. Developing sustainable and effective methods to control ARTS requires basic knowledge of the biology of A. tenella and the nature of interactions between the two insects. A study on the nest distribution and composition of A. tenella in various vegetation types prevailin...

  14. Recovery of Methane Consumption by Secondary Forests in the Amazon River Basin

    Science.gov (United States)

    Webster, K. D.; Meredith, L. K.; Piccini, W.; Pedrinho, A.; Nüsslein, K.; Van Haren, J. L. M.; Camargo, P. B. D.; Mui, T. S.; Saleska, S. R.

    2017-12-01

    Methane (CH4) is a major greenhouse gas in Earth's atmosphere and its atmospheric global mole fraction has roughly doubled since the start of the industrial revolution. The tropics are thought to be a major CH4 emitter, with the Amazon River Basin estimated to contribute 7 % of the annual flux to the atmosphere. The Amazon has experienced extensive land use change during the past 30 years, but we lack an understanding of the qualitative and quantitative effects of land use change on CH4 flux from the Amazon and the associated reasons. To illuminate the factors controlling CH4 flux across land use gradients in the Amazon we measured the CH4 fluxes and will measure the associated stable isotopic composition from pastures, primary forests, and secondary forests, at Ariquemes (Western Amazon, more deforested), and Santarem (Eastern Amazon, less deforested), Brazil. The sites near Santarem were sampled in June of 2016 and the sites near Ariquemes were sampled in March and April of 2017, both at the end of the wet season. Little difference was observed between land use types in Santarem with each land use type slightly consuming atmospheric CH4. However, pasture fluxes at Ariquemes were higher (+520 μg-C m-2 hr-1) than in primary (0 μg-C m-2 hr-1) and secondary forests (-20 μg-C m-2 hr-1; p = 6*10-4). CH4 flux from individual Santarem sites was not correlated with environmental variables. CH4 flux from Airquemes was correlated with several parameters across all samples including soil temperature (p = 7*10-4), and soil humidity (p = 0.02). Despite the fact that pastures experienced higher soil temperatures than forest soils this appears to be a low predictor of CH4 flux from these environments as it was seen at both Santarem and Ariquemes. The analysis of the stable isotopic composition of CH4 from these chambers will aid in understanding the competing processes of microbial CH4 consumption and production in these soils and why pastures may become CH4 sources and

  15. 78 FR 65609 - Medicine Bow-Routt National Forests and Thunder Basin National Grassland; Wyoming; Thunder Basin...

    Science.gov (United States)

    2013-11-01

    ... National Grassland; Wyoming; Thunder Basin National Grassland Prairie Dog Amendment Environmental Impact... Cooperating Agencies. No changes to the Proposed Action or Purpose of and Need for Action have been made... alternatives will be analyzed in the Thunder Basin National Grassland Prairie Dog Amendment EIS. The EIS will...

  16. Impacts of logging and hunting on western lowland gorilla (Gorilla gorilla gorilla) populations and consequences for forest regeneration. A review

    OpenAIRE

    Haurez, B.; Petre, CA.; Doucet, JL.

    2013-01-01

    Timber exploitation is rapidly expanding throughout the Congo Basin. Forest areas assigned to timber harvesting have sharply expanded over the decades and logging concessions now largely overlap with the range of western lowland gorilla (Gorilla gorilla gorilla Savage & Wyman, 1847). However this species, which is considered as critically endangered by IUCN, could play an essential role in maintaining the structure and composition of tropical rainforest notably through seed dispersal services...

  17. Analysis of the spatial dynamics and drivers of forest cover change in the Lempa River Basin of El Salvador

    Science.gov (United States)

    Castaneda, Hector

    This work studies the changes of forest cover that have happened in the Lempa River Basin of El Salvador during the period 1979-2003. Although historically the trend has been towards the loss of forest cover since colonial times, over the period of study a large increase in forest cover was detected. The main tool of evaluation was the analysis of LANDSAT satellite imagery. Images for the dates 1979, 1990-91, and 2003 were classified into forest and noon-forest land covers. Then the changes in land cover were analyzed to determine what were the social, geophysical and climatic drivers determining why and where these new forest appeared. The results indicate that there has been an overall increase in forest cover from 20% in 1979 to 43% in 2003. Although there has been extensive deforestation, this has happened mostly around the main urban centers within the basin. In the more rural and remote areas, the tendency has been towards a resurgence in forest cover. The increase in forest was found to be significantly related to remittances, inaccessibility to roads and markets, density of urban populations, poverty and the civil war of the 1980s. Among the geospatial factors that determined where deforestation and reforestation happened were distance to roads and urban centers, slope, elevation, land use capability, and irrigation potential. The results indicate that the tendency in the future will be towards further reforestation but at a slower rate. Although reforestation and deforestation happened simultaneously, there are clear differences in the spatial patterns that each of these phenomena follow. In terms of climate, it was found areas subjected to inter-annual rainfall extremes due to El Nino Southern Oscillation, particularly areas with low agricultural potential, were more likely to be abandoned and left to revert to forest than those with more stable rainfall. The results of this study support the hypothesis that El Salvador is undergoing a Forest Transition

  18. GIS environmental information analysis of the Darro River basin as the key for the management and hydrological forest restoration.

    Science.gov (United States)

    Fernandez, Paz; Delgado, Expectación; Lopez-Alonso, Mónica; Poyatos, José Manuel

    2018-02-01

    This article presents analyses of soil and environmental information for the Darro River basin (Granada-Spain) preliminary to its hydrological and forestry restoration. These analyses were carried out using a geographical information system (GIS) and employing a new procedure that adapts hydrological forest-restoration methods. The complete analysis encompasses morphological conditions, soil and climate characteristics as well as vegetation and land use. The study investigates soil erosion in the basin by using Universal Soil Loss Equation (USLE) and by mapping erosion fragility units. The results are presented in a set of maps and their analysis, providing the starting point for river basin management and the hydrological and forestry-restoration project that was approved at the end of 2015. The presence of soft substrates (e.g. gravel and sand) indicates that the area is susceptible to erosion, particularly the areas that are dominated by human activity and have little soil protection. Finally, land use and vegetation cover were identified as key factors in the soil erosion in the basin. According to the results, river authorities have included several measures in the restoration project aimed at reducing the erosion and helping to recover the environmental value of this river basin and to include it in recreation possibilities for the community of Granada. The presented analytical approach, designed by the authors, would be useful as a tool for environmental restoration in other small Mediterranean river basins. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Forest Patch Size, Land Use, and Mesic Forest Herbs in the French Broad River Basin, North Carolina

    Science.gov (United States)

    Scott M. Pearson; Alan B. Smith; Monica G. Turner

    1998-01-01

    The effect of forest fragmentation on cove-forest herbs was studied in the Southern Blue Ridge Province. Patches of mesic forests were sampled with 4 ha study plots. The coverage and density of herb species were greater in large patches (>200 ha) than in small patches (

  20. Estimating evapotranspiration change due to forest treatment and fire at the basin scale in the Sierra Nevada, California

    Science.gov (United States)

    Roche, J. W.; Goulden, M.; Bales, R. C.

    2017-12-01

    Increased forest evapotranspiration (ET) coupled with snowpack decreases in a warming climate is likely to decrease runoff and increase forest drought stress. Field experiments and modeling suggest that forest thinning can reduce ET and thus increase potential runoff relative to untreated areas. We investigated the potential magnitude and duration of ET decreases resulting from forest-thinning treatments and fire using a robust empirical relation between Landsat-derived mean-annual normalized difference vegetation index (NDVI) and annual ET measured at flux towers. Among forest treatments, the minimum observed NDVI change required to produce a significant departure from control plots with NDVI of about 0.70 was -0.07 units, corresponding to a basal-area reduction of 3.1 m2 ha-1, and equivalent to an estimated ET reduction of -102 mm yr-1. Intensive thinning in highly productive forests that approached pre-fire-exclusion densities reduced basal area by 40-50%, generating estimated ET reductions of 152-216 mm yr-1 over five years following treatment. Between 1990 and 2008, fires in the American River basin generated more than twice the ET reduction per unit area than those in the Kings River basin, corresponding to greater water and energy limitations in the latter and greater fire severity in the former. A rough extrapolation of these results to the entire American River watershed, much of which would have burned naturally during this 19-year period, could result in ET reductions that approach 10% of full natural flows for drought years and 5% averaged over all years. This work demonstrates the potential utility to estimate forest ET change at the patch scale, which in turn may allow managers to estimate thinning benefits in areas lacking detailed hydrologic measurements.

  1. Change in the forested and developed landscape of the Lake Tahoe basin, California and Nevada, USA, 1940-2002

    Science.gov (United States)

    Raumann, C.G.; Cablk, Mary E.

    2008-01-01

    The current ecological state of the Lake Tahoe basin has been shaped by significant landscape-altering human activity and management practices since the mid-1850s; first through widespread timber harvesting from the 1850s to 1920s followed by urban development from the 1950s to the present. Consequences of landscape change, both from development and forest management practices including fire suppression, have prompted rising levels of concern for the ecological integrity of the region. The impacts from these activities include decreased water quality, degraded biotic communities, and increased fire hazard. To establish an understanding of the Lake Tahoe basin's landscape change in the context of forest management and development we mapped, quantified, and described the spatial and temporal distribution and variability of historical changes in land use and land cover in the southern Lake Tahoe basin (279 km2) from 1940 to 2002. Our assessment relied on post-classification change detection of multi-temporal land-use/cover and impervious-surface-area data that were derived through manual interpretation, image processing, and GIS data integration for four dates of imagery: 1940, 1969, 1987, and 2002. The most significant land conversion during the 62-year study period was an increase in developed lands with a corresponding decrease in forests, wetlands, and shrublands. Forest stand densities increased throughout the 62-year study period, and modern thinning efforts resulted in localized stand density decreases in the latter part of the study period. Additionally forests were gained from succession, and towards the end of the study period extensive tree mortality occurred. The highest rates of change occurred between 1940 and 1969, corresponding with dramatic development, then rates declined through 2002 for all observed landscape changes except forest density decrease and tree mortality. Causes of landscape change included regional population growth, tourism demands

  2. Vegetation Succession on Degraded Sites in the Pomacochas Basin (Amazonas, N Peru—Ecological Options for Forest Restoration

    Directory of Open Access Journals (Sweden)

    Helge Walentowski

    2018-02-01

    Full Text Available The Andes of northern Peru are still widely covered with forests, but increasingly suffer from habitat fragmentation. Subsequent soil degradation often leads to the abandonment of overused forests and pastures. Ecological knowledge on the restoration potential, e.g., on dependencies of soil conditions and altitude, is scarce. Therefore, we compared soil and vegetation patterns along nine transects within the upper Pomacochas Basin, which is an important biodiversity corridor along the Andes, between remaining forests, succession sites and pastures. Anthropogenic successional and disturbance levels, geological substrate, and altitude have the most important ecological impacts on vegetation and tree species composition. Species responded to sandstone versus calcareous substrates, but also to depths of the organic soil layer, and light conditions. The absence of organic layers under pastures contrasted with the accumulation of thick organic layers under forest cover. Vegetation composition at succession sites revealed certain starting points (herbal stage, bush stage, or secondary forest for restoration that will determine the length of regeneration paths. Pre-forest patches of Alchornea sp. and Parathesis sp. may act as habitat stepping stones for expeditiously restoring biocorridors for wildlife. The key findings can contribute to the sustainable use and conservation of biodiversity in a fragile ecoregion.

  3. Decadal change of forest biomass carbon stocks and tree demography in the Delaware River Basin

    Science.gov (United States)

    Bing Xu; Yude Pan; Alain F. Plante; Arthur Johnson; Jason Cole; Richard Birdsey

    2016-01-01

    Quantifying forest biomass carbon (C) stock change is important for understanding forest dynamics and their feedbacks with climate change. Forests in the northeastern U.S. have been a net carbon sink in recent decades, but C accumulation in some northern hardwood forests has been halted due to the impact of emerging stresses such as invasive pests, land use change and...

  4. Country Presentation Congo

    International Nuclear Information System (INIS)

    Mwata, P.K.; SAKI, A.; KAZADI, J.

    2010-01-01

    Illicit trafficking of radioactive minerals, precious metals and nuclear materials is generally expanded practice in some parts of the Democratic Republic of Congo. The phenomenon took place early in 1990 and amplified from 1998. The main causes of this practice are political instability that led to general poverty among population and the lack of legal framework governing the exploitation of minerals. Nuclear Illicit trafficking in Congo concerns radioactive mineral sand precious metals in eastern and southern parts of the country. The unfavorable political environment that took place in Congo in the 1990s resulted in local manpower and mine workers immigrating to neighboring countries. A great fraction of these new jobless started exploiting abandoned mines residues searching for Cu, Co and Au for survival. First cases of illicit exploitation of uranium minerals were reported very soon after rock sliding that occurred in 2004 on Shinkolobwe site in Katanga region. This uncontrolled mineral exploitation got worse when several mining companies were licensed by GECAMINES company to explore, exploit, purchase minerals from individuals and export raw materials and concentrates.

  5. Thermal Characteristics and Bacterial Diversity of Forest Soil in the Haean Basin of Korea

    OpenAIRE

    Kim, Heejung; Lee, Jin-Yong; Lee, Kang-Kun

    2014-01-01

    To predict biotic responses to disturbances in forest environments, it is important to examine both the thermophysical properties of forest soils and the diversity of microorganisms that these soils contain. To predict the effects of climate change on forests, in particular, it is essential to understand the interactions between the soil surface, the air, and the biological diversity in the soil. In this study, the temperature and thermal properties of forest soil at three depths at a site in...

  6. Forest vegetation in the upper Iara basin. Considerations on plants diversit

    OpenAIRE

    Ilie-Adrian Stoica

    2011-01-01

    . Forests cover important areas in Romania, but are poorly investigated from a biological point of view. Forestry studies are focused on economic productivity, while biological studies have focused on phytosociological descriptions. Biodiversity measures have been rarely used in Romania to describe forest environments. This study is an attempt to link classical biologic forest studies with more modern statistical methods of investigation. The diversity of 65 forest relevées from the upper Iar...

  7. Forests

    Science.gov (United States)

    Louis R. Iverson; Mark W. Schwartz

    1994-01-01

    Originally diminished by development, forests are coming back: forest biomass is accumulating. Forests are repositories for many threatened species. Even with increased standing timber, however, biodiversity is threatened by increased forest fragmentation and by exotic species.

  8. Using ALS and MODIS data to evaluate degradation in different forests types over the Xingu basin - Brazilian Amazon

    Science.gov (United States)

    Moura, Y.; Aragão, L. E.; Galvão, L. S.; Dalagnol, R.; Lyapustin, A.; Santos, E. G.; Espirito-Santo, F.

    2017-12-01

    Degradation of Amazon rainforests represents a vital threat to carbon storage, climate regulation and biodiversity; however its effect on tropical ecosystems is largely unknown. In this study we evaluate the effects of forest degradation on forest structure and functioning over the Xingu Basin in the Brazilian Amazon. The vegetation types in the area is dominated by Open Ombrophilous Forest (Asc), Semi-decidiuous Forest (Fse) and Dense Ombrophilous Forest (Dse). We used Airborne Laser Scanning (ALS) data together with time series of optical remote sensing images from the Moderate Resolution Imaging Spectroradiometer (MODIS) bi-directional corrected using the Multi-Angle Implementation for Atmospheric Correction (MAIAC). We derive time-series (2008 to 2016) of the Enhanced Vegetation Index (EVI) and Green-Red Normalized Difference (GRND) to analyze the dynamics of degraded areas with related changes in canopy structure and greenness values, respectively. Airborne ALS measurements showed the largest tree heights in the Dse class with values up to 40m tall. Asc and Fse vegetation types reached up to 30m and 25m in height, respectively. Differences in canopy structure were also evident from the analysis of canopy volume models (CVMs). Asc showed higher proportion of sunlit, as expected for open forest types. Fse showed gaps predominantly in lower height levels, and a higher overall proportion of shaded crown. Full canopy closure was reached at about15 m height for both Asc and Dse, and at about 20 m height for Fse. We also used a base map of degraded areas (available from Imazon - Instituto do Homen e Meio Ambiente da Amazônia) to follow these regions throughout time using EVI and GRND from MODIS. All three forest types displayed seasonal cycles. Notable differences in amplitude were detected during the periods when degradation occurred and both indexes showed a decrease in their response. However, there were marked differences in timing and amplitude depending on

  9. 78 FR 72860 - White River National Forest; Summit County, CO; 2013 Arapahoe Basin Improvements EIS

    Science.gov (United States)

    2013-12-04

    ... environmental impact statement. SUMMARY: Arapahoe Basin Ski Area (A-Basin) has submitted a proposal to the White... Development Plan (MDP). The WRNF has accepted this proposal, and is preparing an Environmental Impact.... The Proposed Action is designed to: Provide The Beavers with snow safety operations and ski patrol...

  10. Floristic and structural status of forests in permanent preservation areas of Moju river basin, Amazon region.

    Science.gov (United States)

    Oliveira, J C; Vieira, I C G; Almeida, A S; Silva, C A

    2016-01-01

    The goal of this study is to analyze the floristic patterns and the structure of disturbed and undisturbed upland forests, in Permanent Preservation Areas (PPAs) along the Moju river, in the Brazilian state of Pará. Trees with a diameter equal to or larger than 10cm at 1.30m from the ground (DBH) ≥10cm were analyzed for the upper stratum. For the middle stratum, individuals with DBH between 4.99 and 9.99cm were sampled. Forty-five families and 221 species were found in disturbed forests, and 43 families and 208 species in undisturbed forests. Floristic similarity was high between strata and between forest types, with values above 50%. Similarity was highest between middle strata. The most species-abundant families in undisturbed forests were Fabaceae, Sapotaceae, Chrysobalanaceae and Myrtaceae; the species with the highest density there were Eschweilera grandiflora, Licania sclerophylla and Zygia cauliflora. In disturbed forests, the dominant families were Fabaceae, Sapotaceae, Lecythidaceae and Melastomataceae. The Shannon-Wiener diversity index was 3.21 for undisturbed forests and 2.85 for disturbed forests. Non-metric multidimensional scaling (MDS) analysis did not group the forests by their floristic composition in both upper and middle strata. Overall, the PPA forests along the Moju river, even if disturbed, did not show major floristic changes but substantially change their structural characteristics.

  11. Floristic and structural status of forests in permanent preservation areas of Moju river basin, Amazon region

    Directory of Open Access Journals (Sweden)

    J. C. Oliveira

    Full Text Available Abstract The goal of this study is to analyze the floristic patterns and the structure of disturbed and undisturbed upland forests, in Permanent Preservation Areas (PPAs along the Moju river, in the Brazilian state of Pará. Trees with a diameter equal to or larger than 10cm at 1.30m from the ground (DBH ≥10cm were analyzed for the upper stratum. For the middle stratum, individuals with DBH between 4.99 and 9.99cm were sampled. Forty-five families and 221 species were found in disturbed forests, and 43 families and 208 species in undisturbed forests. Floristic similarity was high between strata and between forest types, with values above 50%. Similarity was highest between middle strata. The most species-abundant families in undisturbed forests were Fabaceae, Sapotaceae, Chrysobalanaceae and Myrtaceae; the species with the highest density there were Eschweilera grandiflora, Licania sclerophylla and Zygia cauliflora. In disturbed forests, the dominant families were Fabaceae, Sapotaceae, Lecythidaceae and Melastomataceae. The Shannon-Wiener diversity index was 3.21 for undisturbed forests and 2.85 for disturbed forests. Non-metric multidimensional scaling (MDS analysis did not group the forests by their floristic composition in both upper and middle strata. Overall, the PPA forests along the Moju river, even if disturbed, did not show major floristic changes but substantially change their structural characteristics.

  12. ADSORPSI CONGO RED PADA HUMIN HASIL ISOLASI DARI TANAH HUTAN DAMAR BATURRADEN PURWOKERTO

    Directory of Open Access Journals (Sweden)

    Roy Andreas

    2008-05-01

    Full Text Available Congo red is one of dyes-stuff in textile industry wastwater. If it is thrown directly without waste management process, the dyes could pollute environtment, especially soil. Humin has OH phenolic and carboxylic functional group which can interacted with congo red. The aim of this study is recognize humin characteristic from the soil of Baturraden resin forest, determine the adsorption capacity and isotherm adsorption pattern of congo red by humin from the soil of Baturraden resin forest. Humin in this study is isolated from the soil of Baturraden resin forest. soil cleared of gravel and dirt, then it extracted by using NaOH of nitrogen atmosphere and purified to applies mixture HCl:HF. Humin that is obtained is used to be interacted with dyes with various contact time, various of pH and concentration of congo red so that the adsorption capacities and isotherm adsorption pattern can be obtained. Result of the study showed that the humin has water content 34.92 %, dust content 8.64 %, total acidity 475 cmol/Kg, carboxylic rate 272.5 cmol/Kg, and OH Phenolic rate 202.5 cmol/Kg. The optimum contact time of congo red adsorption by humin is 40 minutes, with optimum pH is 7, adsorption capacities 57.14 mg/g and isotherm adsorption pattern of congo red by humin is follow the pattern of Langmuir isotherm adsorption.

  13. Future climate change challenges to sustainable forest management in the Zambezi basin

    CSIR Research Space (South Africa)

    Muchuru, S

    2015-09-01

    Full Text Available in the drive towards sustainable forest management. Africa should strive towards continued democratization, good governance, regional cooperation and integration to harness the huge opportunities in the forest sector. Bibliography African Development Bank... forestry: a few observed trends and issues to watch Godwin Kowero opinion piece Africa’s institutional capacity to manage its forests August B. Temu a donoR’s peRspecTiVe on FoResT secToR deVelopMenT in aFRica: The case of Finnish development aid Vesa...

  14. Functional community structure of African monodominant Gilbertiodendron dewevrei forest influenced by local environmental filtering.

    Science.gov (United States)

    Kearsley, Elizabeth; Verbeeck, Hans; Hufkens, Koen; Van de Perre, Frederik; Doetterl, Sebastian; Baert, Geert; Beeckman, Hans; Boeckx, Pascal; Huygens, Dries

    2017-01-01

    Monodominant patches of forest dominated by Gilbertiodendron dewevrei are commonly found in central African tropical forests, alongside forests with high species diversity. Although these forests are generally found sparsely distributed along rivers, their occurrence is not thought to be (clearly) driven by edaphic conditions but rather by trait combinations of G. dewevrei that aid in achieving monodominance. Functional community structure between these monodominant and mixed forests has, however, not yet been compared. Additionally, little is known about nondominant species in the monodominant forest community. These two topics are addressed in this study. We investigate the functional community structure of 10 one-hectare plots of monodominant and mixed forests in a central region of the Congo basin, in DR Congo. Thirteen leaf and wood traits are measured, covering 95% (basal area weighted) of all species present in the plots, including leaf nutrient contents, leaf isotopic compositions, specific leaf area, wood density, and vessel anatomy. The trait-based assessment of G. dewevrei shows an ensemble of traits related to water use and transport that could be favorable for its location near forest rivers. Moreover, indications have been found for N and P limitations in the monodominant forest, possibly related to ectomycorrhizal associations formed with G. dewevrei . Reduced leaf N and P contents are found at the community level for the monodominant forest and for different nondominant groups, as compared to those in the mixed forest. In summary, this work shows that environmental filtering does prevail in the monodominant G. dewevrei forest, leading to lower functional diversity in this forest type, with the dominant species showing beneficial traits related to its common riverine locations and with reduced soil N and P availability found in this environment, both coregulating the tree community assembly.

  15. Historical fire regime and forest variability on two eastern Great Basin fire-sheds (USA)

    Science.gov (United States)

    Stanley G. Kitchen

    2012-01-01

    Proper management of naturally forested landscapes requires knowledge of key disturbance processes and their effects on species composition and structure. Spatially-intensive fire and forest histories provide valuable information about how fire and vegetation may vary and interact on heterogeneous landscapes. I constructed 800-year fire and tree recruitment...

  16. Looking closer at the Congo

    DEFF Research Database (Denmark)

    Jansson, Johanna; Jiang, Wenran

    2011-01-01

    An NGO report on Chinese investment in the Democratic Republic of Congo opens a vital debate, but its methodology leaves the reader wanting a fuller version of the facts, write Johanna Jansson and Jiang Wenran.......An NGO report on Chinese investment in the Democratic Republic of Congo opens a vital debate, but its methodology leaves the reader wanting a fuller version of the facts, write Johanna Jansson and Jiang Wenran....

  17. The deforestation of rural areas in the Lower Congo Province.

    Science.gov (United States)

    Iloweka, Ernest Manganda

    2004-12-01

    The Lower Congo is one of eleven provinces in the Democratic Republic of Congo, and is located southwest of Kinshasa Town Province. It has an area of approximately 53.947 km2 with a population of 1,504,361 at an estimated 237 persons per km2. The Province comprises five districts, including Lukaya and Cataracts where rural poverty is severe and the population struggle to make a living through agriculture and woodcutting. These activities result in excessive resource exploitation. The high demand for foodstuffs and the high consumption of wood (for energy, construction and export) in Kinshasa, the capital city of the Democratic Republic of Congo and the expanding towns of Matadi and Boma in the Lower Congo Province, are speeding the deforestation rate and unbalancing forest ecosystems. In addition there is the stress resulting from reduced josher (the rest period for agriculture ground), plus climate change and erosion. The phenomena that that we need to address in these two districts include deforestation, reduced josher, excessive agriculture, erosion, burning and climate change which taken together largely explain the current soil degradation. These areas are marked by excessive post deforestation savannah formation and extended areas of sandy soil, distributed throughout grass and shrub savannahs. This desertification, which is rampant in Lukaya and Cataracts, risks imprisoning the rural population in a vicious cycle of poverty if adequate solutions are not found.

  18. Export of nutrients and major ionic solutes from a rain forest catchment in the Central Amazon Basin

    Science.gov (United States)

    Lesack, Lance F. W.

    1993-03-01

    The relative roles of base flow runoff versus storm flow runoff versus subsurface outflow in controlling total export of solutes from a 23.4-ha catchment of undisturbed rain forest in the central Amazon Basin were evaluated from water and solute flux measurements performed over a 1 year period. Solutes exported via 173 storms during the study were estimated from stream water samples collected during base flow conditions and during eight storms, and by utilizing a hydrograph separation technique in combination with a mixing model to partition storm flow from base flow fluxes. Solutes exported by subsurface outflow were estimated from groundwater samples from three nests of piezometers installed into the streambed, and concurrent measurements of hydraulic conductivity and hydraulic head gradients. Base flow discharge represented 92% of water outflow from the basin and was the dominant pathway of solute export. Although storm flow discharge represented only 5% of total water outflow, storm flow solute fluxes represented up to 25% of the total annual export flux, though for many solutes the portion was less. Subsurface outflow represented only 2.5% of total water outflow, and subsurface solute fluxes never represented more than 5% of the total annual export flux. Measurement errors were relatively high for storm flow and subsurface outflow fluxes, but cumulative measurement errors associated with the total solute fluxes exported from the catchment, in most cases, ranged from only ±7% to 14% because base flow fluxes were measured relatively well. The export fluxes of most solutes are substantially less than previously reported for comparable small catchments in the Amazon basin, and these differences cannot be reconciled by the fact that storm flow and subsurface outflows were not appropriately measured in previous studies.

  19. Forest carnivore conservation and management in the interior Columbia basin: issues and environmental correlates.

    Science.gov (United States)

    Gary W. Witmer; Sandra K. Martin; Rodney D. Sayler

    1998-01-01

    Forest carnivores in the Pacific Northwest include 11 medium to large-sized mammalian species of canids, felids, mustelids, and ursids. These carnivores have widely differing status in the region, with some harvested in regulated furbearer seasons, some taken for depredations, and some protected because of rarity. Most large carnivores have declined in numbers or range...

  20. Road Expansion and the Fate of Africa's Tropical Forests

    Directory of Open Access Journals (Sweden)

    William F. Laurance

    2017-07-01

    Full Text Available The tropical forests of Africa are experiencing unprecedented changes as a result of a rapid proliferation of roads and other infrastructure. These projects are dramatically increasing access to relatively unexploited regions, particularly in the greater Congo Basin. We highlight some of the most important new projects and describe in detail an ongoing debate about a particular proposed development, the Cross River Superhighway in Nigeria. The scale and pace of new transportation projects, and the profound environmental changes they could bring, underscore a dire need for proactive land-use planning, capacity building, and environmental assessment in the nations of Equatorial Africa. It is no exaggeration to suggest that, unless carefully managed to ensure sustainability, the spate of planned and ongoing projects could irreparably diminish the forests and wildlife populations of Africa's most biologically diverse regions.

  1. Scorpion envenomation in pygmies from Democratic Republic of Congo, the example of Pelenge Center, Lomela, DRC

    Directory of Open Access Journals (Sweden)

    E Biezakala Mudiandambu

    2012-01-01

    Full Text Available In a survey among the pygmies of central Democratic Republic of Congo, the incidence of scorpion stings seemed very high with a severity greater than expected. Species responsible were not identified. Specific studies are needed to clarify the risk emerging in the equatorial African forest.

  2. Forests

    International Nuclear Information System (INIS)

    Melin, J.

    1997-01-01

    Forests have the capacity to trap and retain radionuclides for a substantial period of time. The dynamic behaviour of nutrients, pollution and radionuclides in forests is complex. The rotation period of a forest stand in the Nordic countries is about 100 years, whilst the time for decomposition of organic material in a forest environment can be several hundred years. This means that any countermeasure applied in the forest environment must have an effect for several decades, or be reapplied continuously for long periods of time. To mitigate the detrimental effect of a contaminated forest environment on man, and to minimise the economic loss in trade of contaminated forest products, it is necessary to understand the mechanisms of transfer of radionuclides through the forest environment. It must also be stressed that any countermeasure applied in the forest environment must be evaluated with respect to long, as well as short term, negative effects, before any decision about remedial action is taken. Of the radionuclides studied in forests in the past, radiocaesium has been the main contributor to dose to man. In this document, only radiocaesium will be discussed since data on the impact of other radionuclides on man are too scarce for a proper evaluation. (EG)

  3. Forest Conversion, Agricultural Transitions and the Influence of Multi-scale Market Factors in Southwest Cameroon

    Science.gov (United States)

    Ordway, E.; Lambin, E.; Asner, G. P.

    2015-12-01

    The changing structure of demand for commodities associated with food security and energy has had a startling impact on land use change in tropical forests in recent decades. Yet, the composition of conversion in the Congo basin remains a major uncertainty, particularly with regards to the scale of drivers of change. Owing to rapid expansion of production globally and longstanding historical production locally in the Congo basin, oil palm offers a lens through which to evaluate local land use decisions across a spectrum of small- to large-scales of production as well as interactions with regional and global supply chains. We examined the effect of global commodity crop expansion on land use change in Southwest Cameroon using a mixed-methods approach to integrate remote sensing, field surveys and socioeconomic data. Southwest Cameroon (2.5 Mha) has a long history of large- and small-scale agriculture, ranging from mixed crop subsistence agriculture to large monocrop plantations of oil palm, cocoa, and rubber. Trends and spatial patterns of forest conversion and agricultural transitions were analyzed from 2000-2015 using satellite imagery. We used economic, demographic and field survey datasets to assess how regional and global market factors and local commodity crop decisions affect land use patterns. Our results show that oil palm is a major commodity crop expanding in this region, and that conversion is occurring primarily through expansion by medium-scale producers and local elites. Results also indicate that global and regional supply chain dynamics influence local land use decision making. This research contributes new information on land use patterns and dynamics in the Congo basin, an understudied region. More specifically, results from this research contribute information on recent trends of oil palm expansion in Cameroon that will be used in national land use planning strategies.

  4. An initial investigation into the organic matter biogeochemistry of the Congo River

    Science.gov (United States)

    Spencer, Robert G.M.; Hernes, Peter J.; Aufdenkampe, Anthony K.; Baker, Andy; Gulliver, Pauline; Stubbins, Aron; Aiken, George R.; Dyda, Rachael Y.; Butler, Kenna D.; Mwamba, Vincent L.; Mangangu, Arthur M.; Wabakanghanzi, Jose N.; Six, Johan

    2012-01-01

    The Congo River, which drains pristine tropical forest and savannah and is the second largest exporter of terrestrial carbon to the ocean, was sampled in early 2008 to investigate organic matter (OM) dynamics in this historically understudied river basin. We examined the elemental (%OC, %N, C:N), isotopic (δ13C, Δ14C, δ15N) and biochemical composition (lignin phenols) of coarse particulate (>63 μm; CPOM) and fine particulate (0.7–63 μm; FPOM) OM and DOC, δ13C, Δ14C and lignin phenol composition with respect to dissolved OM (14C = -62.2 ± -13.2‰, n = 5) compared to CPOM and DOM (mean Δ14C = 55.7 ± 30.6‰, n = 4 and 73.4 ± 16.1‰, n = 5 respectively). The modern radiocarbon ages for DOM belie a degraded lignin compositional signature (i.e. elevated acid:aldehyde ratios (Ad:Al) relative to CPOM and FPOM), and indicate that the application of OM degradation patterns derived from particulate phase studies to dissolved samples needs to be reassessed: these elevated ratios are likely attributable to fractionation processes during solubilization of plant material. The relatively low DOM carbon-normalized lignin yields (Λ8; 0.67–1.12 (mg(100 mg OC)-1)) could also reflect fractionation processes, however, they have also been interpreted as an indication of significant microbial or algal sources of DOM. CPOM appears to be well preserved higher vascular plant material as evidenced by its modern radiocarbon age, elevated C:N (17.2–27.1) and Λ8 values (4.56–7.59 (mg(100 mg OC)-1)). In relation to CPOM, the aged FPOM fraction (320–580 ybp 14C ages) was comparatively degraded, as demonstrated by its nitrogen enrichment (C:N 11.4–14.3), lower Λ8 (2.80–4.31 (mg(100 mg OC)-1)) and elevated lignin Ad:Al values similar to soil derived OM. In this study we observed little modification of the OM signature from sample sites near the cities of Brazzaville and Kinshasa to the head of the estuary (~350 km) highlighting the potential for future studies to

  5. The petroleum economy of the Congo

    International Nuclear Information System (INIS)

    Gualbert-Brice Massengo, Ph.D.

    2005-01-01

    The author aims to explain the petroleum phenomena in Congo as a contribution to the truth. The Congo petroleum experience can be seen as a lesson for the next generations and for the other african countries. The Congo Brazzaville, a little country by its population and well equipped in natural and human resources, is become meanwhile a non security area for its inhabitants because of a decreasing economy and a continuous political crisis. (A.L.B.)

  6. Seasonal Snowpack Dynamics and Runoff in a Maritime Forested Basin, Niigata, Japan

    Science.gov (United States)

    Whitaker, A. C.; Sugiyama, H.

    2005-12-01

    Seasonal snowpack dynamics are described through field measurements under contrasting canopy conditions for a mountainous catchment in the Japan Sea region. Microclimatic data, snow accumulation, albedo and lysimeter runoff is given through three complete winter seasons 2002-05 in: (1) mature cedar stand, (2) larch stand, and (3) regenerating cedar stand or opening. The accumulation and melt of seasonal snowpack strongly influences streamflow runoff during December to May, including winter base-flow, mid-winter melt, rain-on-snow, and diurnal peaks driven by radiation melt in spring. Lysimeter runoff at all sites is characterised by constant ground melt of 0.8-1.0 mm/day. Rapid response to mid-winter melt or rainfall shows that the snowpack remains in a ripe or near-ripe condition throughout the snowcover season. Hourly and daily lysimeter discharge was greatest during rain-on-snow with the majority of runoff due to rainfall passing through the snowpack as opposed to snowmelt. For both rain-on-snow and radiation melt events lysimeter discharge was generally greatest at the open site, although there were exceptions such as during interception melt events. During radiation melt instantaneous discharge was up to 4.0 times greater in the opening compared to the mature cedar, and 48-hour discharge was up to 2.5 times greater. Perhaps characteristic of maritime climates, forest interception melt is shown to be important in addition to sublimation in reducing snow accumulation beneath dense canopies. While sublimation represents a loss from the catchment water balance, interception melt percolates through the snowpack and contributes to soil moisture during the winter season. Strong differences in microclimate and snowpack albedo persisted between cedar, larch and open sites, and it is suggested further work is needed to account for this in hydrological simulation models.

  7. Vascular epiphytes of the Atlantic Forest in the Sinos River basin, state of Rio Grande do Sul, Brazil: richness, floristic composition and community structure.

    Science.gov (United States)

    Barbosa, M D; Becker, D F P; Cunha, S; Droste, A; Schmitt, J L

    2015-05-01

    The Atlantic Forest, which has a vast epiphytic richness, is a priority area for preservation, listed as one of the five most important world hotspots. Vascular epiphyte richness, composition and community structure were studied in two fragments, one of the ombrophilous (29º43'42"S and 50º22'00"W) and the other of the seasonal (29º40'54"S and 51º06'56"W) forest, both belonging to the Atlantic Forest biome in the Sinos River basin, Rio Grande do Sul, Brazil. In each fragment, 40 trees, divided into four ecological zones, were analyzed. In each zone, the occurrence of the species was recorded, and the importance value of each species was calculated according to the frequency of phorophytes and intervals, and cover scores. The Shannon index was calculated for the two communities. In the fragment of the ombrophilous forest (F1), 30 epiphytic species were recorded, and in the seasonal forest (F2), 25. The highest importance value was found for Microgramma squamulosa (Kaulf.) de la Sota in both fragments. The diversity indexes for F1 (H'=2.72) and F2 (H'=2.55) were similar and reflected the subtropical location of the areas. The decrease in mean richness in both fragments in zone 3 (internal crown) to zone 4 (external crown) may be associated with time and space availability for epiphyte occupation and microclimate variations. Exclusive species were found in the areas, which suggest that a greater number of preserved fragments may result in a greater number of preserved epiphytic species in the Sinos River basin.

  8. The Westphalian D fossil lepidodendrid forest at Table Head, Sydney Basin, Nova Scotia: Sedimentology, paleoecology and floral response to changing edaphic conditions

    Science.gov (United States)

    Calder, J.H.; Gibling, M.R.; Eble, C.F.; Scott, A.C.; MacNeil, D.J.

    1996-01-01

    Strata of Westphalian D age on the western coast of the Sydney Basin expose a fossil forest of approximately 30 lepidodendrid trees within one of several clastic splits of the Harbour Seam. A mutidisciplinary approach was employed to interpret the origins of the coal bed, the depositional history of the site and the response of the fossil forest to changing edaphic conditions. The megaspore and miospore records indicate that the mire vegetation was dominated by arboreous lycopsids, especially Paralycopodites, with subdominant tree ferns. Petrographic, palynological and geochemical evidence suggest that the Harbour coal bed at Table Head originated as a rheotrophic (cf. planar) mire (eutric histosol). The mire forest is interpreted to have been engulfed by prograding distributary-channel sediments; sparse protist assemblages are suggestive of a freshwater delta-plain lake environment occasionally in contact with brackish waters. Lepidodendrids persisted as site colonizers of clastic substrates even after burial of the rheotrophic peatland and influenced the morphology of deposited sediment, but apparently were unable to colonize distributary channels. Equivocal taxonomic data (compression fossils) show the fossil forest to have been composed of both monocarpic (Lepidodendron) and polycarpic (Diaphorodendron, Paralycopodites, ?Sigillaria) lycopsids, genera recorded in the palynology of the uppermost ply of the underlying coal bed. Comparatively rare within the clastic beds of the fossil forest, however, is the stem compression of Paralycopodites, whose dispersed megapores and miospores dominate the underlying coal bed. Tree diameter data recorded equivalent to breast height indicate a forest of mixed age. These data would appear to suggest that some lepidodendrids employing a polycarpic reproductive strategy were better able to cross the ecological barrier imposed between peat and clastic substrates. Foliar compressions indicate that an understory or stand of

  9. A proposed drainage evolution model for Central Africa—Did the Congo flow east?

    Science.gov (United States)

    Stankiewicz, Jacek; de Wit, Maarten J.

    2006-01-01

    Understanding the origin of Sub-Saharan biodiversity requires knowing the history of the region's paleo-ecosystems. As water is essential for sustaining of life, the evolving geometry of river basins often have influence on local speciation. With this in mind, we analyse drainage patterns in Central and East Africa. Evidence from marine fossils suggests the Congo Basin was submerged for much of the Cretaceous, and after being uplifted drained eastwards through a paleo-Congo river towards the Indian Ocean. Two remnant peneplains in the Congo Basin are interpreted as evidence that this basin was tectonically stable on at least two occasions in the past. The lower peneplain is interpreted as the base level of the drainage pattern that had its outlet in Tanzania, at the present Rufiji Delta that was once over 500 km wide. The Luangwa, today a tributary of the Zambezi river, was a part of this drainage network. This pattern was subsequently disrupted by uplift associated with the East African Rifting in the Oligocene-Eocene (30-40 Ma). The resulting landlocked system was captured in the Miocene (5-15 Ma) by short rivers draining into the Atlantic Ocean, producing the drainage pattern of Central Africa seen today.

  10. Avian diversity and feeding guilds in a secondary forest, an oil palm plantation and a paddy field in riparian areas of the kerian river basin, perak, malaysia.

    Science.gov (United States)

    Azman, Nur Munira; Latip, Nurul Salmi Abdul; Sah, Shahrul Anuar Mohd; Akil, Mohd Abdul Muin Md; Shafie, Nur Juliani; Khairuddin, Nurul Liyana

    2011-12-01

    The diversity and the feeding guilds of birds in three different habitats (secondary forest, oil palm plantation and paddy field) were investigated in riparian areas of the Kerian River Basin (KRB), Perak, Malaysia. Point-count observation and mist-netting methods were used to determine bird diversity and abundance. A total of 132 species of birds from 46 families were recorded in the 3 habitats. Species diversity, measured by Shannon's diversity index, was 3.561, 3.183 and 1.042 in the secondary forest, the paddy field and the oil palm plantation, respectively. The vegetation diversity and the habitat structure were important determinants of the number of bird species occurring in an area. The relative abundance of the insectivore, insectivore-frugivore and frugivore guilds was greater in the forest than in the monoculture plantation. In contrast, the relative abundance of the carnivore, granivore and omnivore guilds was higher in the plantation. The results of the study show that the conversion of forest to either oil palm plantation or paddy fields produced a decline in bird diversity and changes in the distribution of bird feeding guilds.

  11. Genetic and Phenotype [Phenotypic] Catalog of Native Resident Trout of the interior Columbia River Basin : FY-99 Report : Populations of the Pend Oreille, Kettle, and Sanpoil River Basins of Colville National Forest.

    Energy Technology Data Exchange (ETDEWEB)

    Trotter, Patrick C.

    2001-05-01

    The 1994 Fish and Wildlife Program of the Northwest Power Planning Council specifies the recovery and preservation of population health of native resident fishes of the Columbia River Basin. Among the native resident species of concern are interior rainbow trout of the Columbia River redband subspecies Oncorhynchus mykiss gairdneri 1 and westslope cutthroat trout O. clarki lewisi. The westslope cutthroat trout has been petitioned for listing under the U. S. Endangered Species Act (American Wildlands et al. 1997). Before at-risk populations can be protected, their presence and status must be established. Where introgression from introduced species is a concern, as in the case of both westslope cutthroat trout and redband rainbow trout, genetic issues must be addressed as well. As is true with native trout elsewhere in the western United States (Behnke 1992), most of the remaining pure populations of these species in the Columbia River Basin are in relatively remote headwater reaches. The objective of this project is to photo-document upper Columbia Basin native resident trout populations in Washington, and to ascertain their species or subspecies identity and relative genetic purity using a nonlethal DNA technique. FY-99 was year two of a five-year project in which we conducted field visits to remote locations to seek out and catalog these populations. In FY-99 we worked in collaboration with the Colville National Forest and Kalispel Indian Tribe to catalog populations in the northeastern corner of Washington State.

  12. Genetic and phenotype catalog of native resident trout of the interior Columbia River Basin: FY-99 report: populations of the Pend Oreille, Kettle, and Sanpoil River Basins of Colville National Forest/ fiscal year 1999 report; ANNUAL

    International Nuclear Information System (INIS)

    Trotter, Patrick C.

    2001-01-01

    The 1994 Fish and Wildlife Program of the Northwest Power Planning Council specifies the recovery and preservation of population health of native resident fishes of the Columbia River Basin. Among the native resident species of concern are interior rainbow trout of the Columbia River redband subspecies Oncorhynchus mykiss gairdneri 1 and westslope cutthroat trout O. clarki lewisi. The westslope cutthroat trout has been petitioned for listing under the U. S. Endangered Species Act (American Wildlands et al. 1997). Before at-risk populations can be protected, their presence and status must be established. Where introgression from introduced species is a concern, as in the case of both westslope cutthroat trout and redband rainbow trout, genetic issues must be addressed as well. As is true with native trout elsewhere in the western United States (Behnke 1992), most of the remaining pure populations of these species in the Columbia River Basin are in relatively remote headwater reaches. The objective of this project is to photo-document upper Columbia Basin native resident trout populations in Washington, and to ascertain their species or subspecies identity and relative genetic purity using a nonlethal DNA technique. FY-99 was year two of a five-year project in which we conducted field visits to remote locations to seek out and catalog these populations. In FY-99 we worked in collaboration with the Colville National Forest and Kalispel Indian Tribe to catalog populations in the northeastern corner of Washington State

  13. Trace metal distributions in the sediments from river-reservoir systems: case of the Congo River and Lake Ma Vallée, Kinshasa (Democratic Republic of Congo).

    Science.gov (United States)

    Mwanamoki, Paola M; Devarajan, Naresh; Niane, Birane; Ngelinkoto, Patience; Thevenon, Florian; Nlandu, José W; Mpiana, Pius T; Prabakar, Kandasamy; Mubedi, Josué I; Kabele, Christophe G; Wildi, Walter; Poté, John

    2015-01-01

    The contamination of drinking water resources by toxic metals is a major problem in many parts of the world, particularly in dense populated areas of developing countries that lack wastewater treatment facilities. The present study characterizes the recent evolution with time of some contaminants deposited in the Congo River and Lake Ma Vallée, both located in the vicinity of the large city of Kinshasa, capital of Democratic Republic of Congo (DRC). Physicochemical parameters including grain size distribution, organic matter and trace element concentrations were measured in sediment cores sampled from Congo River (n = 3) and Lake Ma Vallée (n = 2). The maximum concentration of trace elements in sediment profiles was found in the samples from the sites of Pool Malebo, with the values of 107.2, 111.7, 88.6, 39.3, 15.4, 6.1 and 4.7 mg kg(-1) for Cr, Ni, Zn, Cu, Pb, As and Hg, respectively. This site, which is characterized by intense human activities, is especially well known for the construction of numerous boats that are used for regular navigation on Congo River. Concerning Lake Ma Vallée, the concentration of all metals are generally low, with maximum values of 26.3, 53.6, 16.1, 15.3, 6.5 and 1.8 mg kg(-1) for Cr, Ni, Zn, Cu, Pb and As, respectively. However, the comparison of the metal profiles retrieved from the different sampled cores also reveals specific variations. The results of this study point out the sediment pollution by toxic metals in the Congo River Basin. This research presents useful tools for the evaluation of sediment contamination of river-reservoir systems.

  14. Managing salinity in Upper Colorado River Basin streams: Selecting catchments for sediment control efforts using watershed characteristics and random forests models

    Science.gov (United States)

    Tillman, Fred; Anning, David W.; Heilman, Julian A.; Buto, Susan G.; Miller, Matthew P.

    2018-01-01

    Elevated concentrations of dissolved-solids (salinity) including calcium, sodium, sulfate, and chloride, among others, in the Colorado River cause substantial problems for its water users. Previous efforts to reduce dissolved solids in upper Colorado River basin (UCRB) streams often focused on reducing suspended-sediment transport to streams, but few studies have investigated the relationship between suspended sediment and salinity, or evaluated which watershed characteristics might be associated with this relationship. Are there catchment properties that may help in identifying areas where control of suspended sediment will also reduce salinity transport to streams? A random forests classification analysis was performed on topographic, climate, land cover, geology, rock chemistry, soil, and hydrologic information in 163 UCRB catchments. Two random forests models were developed in this study: one for exploring stream and catchment characteristics associated with stream sites where dissolved solids increase with increasing suspended-sediment concentration, and the other for predicting where these sites are located in unmonitored reaches. Results of variable importance from the exploratory random forests models indicate that no simple source, geochemical process, or transport mechanism can easily explain the relationship between dissolved solids and suspended sediment concentrations at UCRB monitoring sites. Among the most important watershed characteristics in both models were measures of soil hydraulic conductivity, soil erodibility, minimum catchment elevation, catchment area, and the silt component of soil in the catchment. Predictions at key locations in the basin were combined with observations from selected monitoring sites, and presented in map-form to give a complete understanding of where catchment sediment control practices would also benefit control of dissolved solids in streams.

  15. Sr-isotope stratigraphy and dating of Neo-proterozoic carbonates and glacials from the northern and western parts of the Congo Craton

    International Nuclear Information System (INIS)

    Poidevin, J.L.

    2007-01-01

    Numerous occurrences of Neo-proterozoic carbonate platforms and glacigenic litho-facies are present around the Congo craton. They are especially well developed on its western and northern borders, i.e. in the fore-lands of the West Congo and Oubanguides belts. Sr isotopic stratigraphy enables us to characterize the deposition age of some carbonate units from these two domains. The 87 Sr/ 86 Sr isotopic ratios of limestones from the late 'Haut Shiloango' (0.7068) and the 'Schisto-calcaire' (0.7075) of the West-Congo domain are of post-Sturtian and post-Marinoan ages, respectively. The Lenda carbonates (0.7066) from the Northeast of the Democratic Republic of Congo and the limestones (0.7076) from the Bangui Basin, both in the Oubanguides fore-land, are of pre-Sturtian and post-Marinoan ages, respectively. These data associated with lithostratigraphic correlations allow us to ascribe the 'Bas Congo' lower mixtite (tillite) and the Akwokwo tillite (Lindian) to the Sturtian ice age. In the same way, the 'Bas Congo' upper mixtite (tillite) and the Bondo tillite (Bakouma Basin) are likely Marinoan in age. A new synthetic stratigraphy for these Neo-proterozoic domains is developed. (author)

  16. Understory vegetation in fast-growing tree plantations on savanna soils in Congo

    OpenAIRE

    Loumeto, J.J.; Huttel, Charles

    1997-01-01

    The hypothesis that tree plantations may catalyze the regeneration of natural forest biodiversity was tested through studies of floristic diversity and structure in fast-growing tree plantations in the Congo. Study sites included experimental and industrial plantations on poor sandy coastal soils near Pointe-Noire, and experimental plantations on clay soils near Loudima. The effects of plantations species, plantation age (in 6- to 20-year-old eucalypt stands), disturbance due to herbicide use...

  17. Hydrologic Impacts Associated with the Increased Role of Wildland Fire Across the Rangeland-Xeric Forest Continuum of the Great Basin and Intermountain West, USA

    Science.gov (United States)

    Williams, C. J.; Pierson, F. B.; Robichaud, P. R.; Boll, J.; Al-Hamdan, O. Z.

    2011-12-01

    The increased role of wildland fire across the rangeland-xeric forest continuum in the western United States (US) presents landscape-scale consequences relative runoff and erosion. Concomitant climate conditions and altered plant community transitions in recent decades along grassland-shrubland-woodland-xeric forest transitions have promoted frequent and large wildland fires, and the continuance of the trend appears likely if current or warming climate conditions prevail. Much of the Great Basin and Intermountain West in the US now exists in a state in which rangeland and woodland wildfires stimulated by invasive cheatgrass and dense, horizontal and vertical fuel layers have a greater likelihood of progressing upslope into xeric forests. Drier moisture conditions and warmer seasonal air temperatures, along with dense fuel loads, have lengthened fire seasons and facilitated an increase in the frequency, severity and area burned in mid-elevation western US forests. These changes potentially increase the overall hydrologic vulnerability across the rangeland-xeric forest continuum by spatially and temporally increasing soil surface exposure to runoff and erosion processes. Plot-to-hillslope scale studies demonstrate burning may increase event runoff and/or erosion by factors of 2-40 over small-plots scales and more than 100-fold over large-plot to hillslope scales. Anecdotal reports of large-scale flooding and debris-flow events from rangelands and xeric forests following burning document the potential risk to resources (soil loss, water quality, degraded aquatic habitat, etc.), property and infrastructure, and human life. Such risks are particularly concerning for urban centers near the urban-wildland interface. We do not yet know the long-term ramifications of frequent soil loss associated with commonly occurring runoff events on repeatedly burned sites. However, plot to landscape-scale post-fire erosion rate estimates suggest potential losses of biologically

  18. Crimean-Congo Hemorrhagic Fever

    Directory of Open Access Journals (Sweden)

    Emadi Koochak H

    2003-10-01

    Full Text Available Crimean-Congo hemorrhagic fever (CCHF was first described in the Crimea in 1944 and then in 1956 in congo. CCHF is a viral hemorrhagic fever of the Nairovirus group that belongs to Bunyaviridae family virus. It is transmitted to human by tick bite. The most efficient and common tick that is the vectors of CCHF is a member of the Hyalomma genus which infected many mammals such as livestock, this tick is the main reservoire of virus in nature. Humans also become infected with CCHF virus by direct contact with blood or other infected tissues from livestock or human patients (nosocomial infection. Disease has been found in saharic Africa, Eastern Europe, Pakistan, India and Middle East (specially Iran and Iraq. This disease recently spread in Iran so in 1999 to 2001 at least 222 suspected case(81 definite case reported that led to the death of 15 of 81 cases. It is estimated that 30 percent of the country's cattle are contaminated with this virus."nIn humans, after a short incubation period it appears suddenly with fever, chills, myalgia and GI symptoms followed by severe bleeding and DIC that led to death .If the patient improved, has a long {2-4 weeks convalescence period. Disease diagnosed by clinical manifestations, serologic tests, viral culture and PCR and its specific treatment is oral ribavirin for 10 days, for prevention of disease personal protective measures from tick bite, spraying poison of mews to reduce of ticks crowd, isolation of patients and dis-infection of contaminated personal equipments that who suffering from CCHF is recommended.

  19. Global forest loss disproportionately erodes biodiversity in intact landscapes.

    Science.gov (United States)

    Betts, Matthew G; Wolf, Christopher; Ripple, William J; Phalan, Ben; Millers, Kimberley A; Duarte, Adam; Butchart, Stuart H M; Levi, Taal

    2017-07-27

    Global biodiversity loss is a critical environmental crisis, yet the lack of spatial data on biodiversity threats has hindered conservation strategies. Theory predicts that abrupt biodiversity declines are most likely to occur when habitat availability is reduced to very low levels in the landscape (10-30%). Alternatively, recent evidence indicates that biodiversity is best conserved by minimizing human intrusion into intact and relatively unfragmented landscapes. Here we use recently available forest loss data to test deforestation effects on International Union for Conservation of Nature Red List categories of extinction risk for 19,432 vertebrate species worldwide. As expected, deforestation substantially increased the odds of a species being listed as threatened, undergoing recent upgrading to a higher threat category and exhibiting declining populations. More importantly, we show that these risks were disproportionately high in relatively intact landscapes; even minimal deforestation has had severe consequences for vertebrate biodiversity. We found little support for the alternative hypothesis that forest loss is most detrimental in already fragmented landscapes. Spatial analysis revealed high-risk hot spots in Borneo, the central Amazon and the Congo Basin. In these regions, our model predicts that 121-219 species will become threatened under current rates of forest loss over the next 30 years. Given that only 17.9% of these high-risk areas are formally protected and only 8.9% have strict protection, new large-scale conservation efforts to protect intact forests are necessary to slow deforestation rates and to avert a new wave of global extinctions.

  20. Litter and nutrient flows in tropical upland forest flooded by a hydropower plant in the Amazonian basin.

    Science.gov (United States)

    Pereira, Guilherme Henrique A; Jordão, Henos Carlos K; Silva, Vanessa Francieli V; Pereira, Marcos Gervasio

    2016-12-01

    Extensive areas in the Brazilian Amazon have been flooded for the construction of hydroelectric dams. However, the water regime of these areas affects the dynamics of igarapés (streams) in adjacent terra firme (upland forests). When the reservoirs are filled, the water levels of streams rise above the normal levels and upland bank forests are flooded. We investigated how this flooding affects the litterfall and nutrient input in the upland forests upstream of a hydroelectric dam reservoir in the Central Amazonia. When the reservoir was filled, the forests were flooded and produced more than twice the litter (8.80Mg·ha -1 yr -1 ), with three times more leaves (6.36Mg·ha -1 yr -1 ) than when they were not flooded (4.20 and 1.92Mg·ha -1 yr -1 , respectively). During flooding, the decomposition rate was four times lower in flooded forests (0.328g·g -1 yr -1 ) than in control forests (1.460g·g -1 yr -1 ). Despite this, the flooding did not favor litter or nutrient accumulation. Therefore, dam construction changes the organic matter and nutrient cycling in upland Amazon rainforests. This may influence the important role that they play in organic matter dynamics and could have consequences for the regional carbon balance and, ultimately, global climate. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Drought drove forest decline and dune building in eastern upper Michigan, USA, as the upper Great Lakes became closed basins

    Science.gov (United States)

    Loope, Walter L.; Loope, Henry M.; Goble, Ronald J.; Fisher, Timothy G.; Lytle, David E.; Legg, Robert J.; Wysocki, Douglas A.; Hanson, Paul R.; Young, Aaron R.

    2012-01-01

    Current models of landscape response to Holocene climate change in midcontinent North America largely reconcile Earth orbital and atmospheric climate forcing with pollen-based forest histories on the east and eolian chronologies in Great Plains grasslands on the west. However, thousands of sand dunes spread across 12,000 km2 in eastern upper Michigan (EUM), more than 500 km east of the present forest-prairie ecotone, present a challenge to such models. We use 65 optically stimulated luminescence (OSL) ages on quartz sand deposited in silt caps (n = 8) and dunes (n = 57) to document eolian activity in EUM. Dune building was widespread ca. 10–8 ka, indicating a sharp, sustained decline in forest cover during that period. This decline was roughly coincident with hydrologic closure of the upper Great Lakes, but temporally inconsistent with most pollen-based models that imply canopy closure throughout the Holocene. Early Holocene forest openings are rarely recognized in pollen sums from EUM because faint signatures of non-arboreal pollen are largely obscured by abundant and highly mobile pine pollen. Early Holocene spikes in nonarboreal pollen are recorded in cores from small ponds, but suggest only a modest extent of forest openings. OSL dating of dune emplacement provides a direct, spatially explicit archive of greatly diminished forest cover during a very dry climate in eastern midcontinent North America ca. 10–8 ka.

  2. Implementation of a subcanopy solar radiation model on a forested headwater basin in the Southern Appalachians to estimate riparian canopy density and stream insolation for stream temperature models

    Science.gov (United States)

    Belica, L.; Petras, V.; Iiames, J. S., Jr.; Caldwell, P.; Mitasova, H.; Nelson, S. A. C.

    2016-12-01

    Water temperature is a key aspect of water quality and understanding how the thermal regimes of forested headwater streams may change in response to climatic and land cover changes is increasingly important to scientists and resource managers. In recent years, the forested mountain watersheds of the Southeastern U.S. have experienced changing climatic patterns as well as the loss of a keystone riparian tree species and anticipated hydrologic responses include lower summer stream flows and decreased stream shading. Solar radiation is the main source of thermal energy to streams and a key parameter in heat-budget models of stream temperature; a decrease in flow volume combined with a reduction in stream shading during summer have the potential to increase stream temperatures. The high spatial variability of forest canopies and the high spatio-temporal variability in sky conditions make estimating the solar radiation reaching small forested headwater streams difficult. The Subcanopy Solar Radiation Model (SSR) (Bode et al. 2014) is a GIS model that generates high resolution, spatially explicit estimates of solar radiation by incorporating topographic and vegetative shading with a light penetration index derived from leaf-on airborne LIDAR data. To evaluate the potential of the SSR model to provide estimates of stream insolation to parameterize heat-budget models, it was applied to the Coweeta Basin in the Southern Appalachians using airborne LIDAR (NCALM 2009, 1m resolution). The LIDAR derived canopy characteristics were compared to current hyperspectral images of the canopy for changes and the SSR estimates of solar radiation were compared with pyranometer measurements of solar radiation at several subcanopy sites during the summer of 2016. Preliminary results indicate the SSR model was effective in identifying variations in canopy density and light penetration, especially in areas associated with road and stream corridors and tree mortality. Current LIDAR data and

  3. The spatial distribution and temporal variation of desert riparian forests and their influencing factors in the downstream Heihe River basin, China

    Science.gov (United States)

    Ding, Jingyi; Zhao, Wenwu; Daryanto, Stefani; Wang, Lixin; Fan, Hao; Feng, Qiang; Wang, Yaping

    2017-05-01

    Desert riparian forests are the main restored vegetation community in Heihe River basin. They provide critical habitats and a variety of ecosystem services in this arid environment. Since desert riparian forests are also sensitive to disturbance, examining the spatial distribution and temporal variation of these forests and their influencing factors is important to determine the limiting factors of vegetation recovery after long-term restoration. In this study, field experiment and remote sensing data were used to determine the spatial distribution and temporal variation of desert riparian forests and their relationship with the environmental factors. We classified five types of vegetation communities at different distances from the river channel. Community coverage and diversity formed a bimodal pattern, peaking at the distances of 1000 and 3000 m from the river channel. In general, the temporal normalized difference vegetation index (NDVI) trend from 2000 to 2014 was positive at different distances from the river channel, except for the region closest to the river bank (i.e. within 500 m from the river channel), which had been undergoing degradation since 2011. The spatial distribution of desert riparian forests was mainly influenced by the spatial heterogeneity of soil properties (e.g. soil moisture, bulk density and soil particle composition). Meanwhile, while the temporal variation of vegetation was affected by both the spatial heterogeneity of soil properties (e.g. soil moisture and soil particle composition) and to a lesser extent, the temporal variation of water availability (e.g. annual average and variability of groundwater, soil moisture and runoff). Since surface (0-30 cm) and deep (100-200 cm) soil moisture, bulk density and the annual average of soil moisture at 100 cm obtained from the remote sensing data were regarded as major determining factors of community distribution and temporal variation, conservation measures that protect the soil structure

  4. Trends in Surface-Water Nitrate-N Concentrations and Loads from Predominantly-Forested Watersheds of the Chesapeake Bay Basin

    Science.gov (United States)

    Eshleman, K. N.

    2011-12-01

    Water quality monitoring data from streams and rivers provide the "gold standard" by which progress toward achieving real reductions in nutrient loadings to Chesapeake Bay must ultimately be assessed. The most recent trend results posted at the Chesapeake Bay Program (CBP) website reveal that a substantial percentage of tributaries are now showing long-term declines in flow-adjusted concentrations of nutrients and sediments: 22 sites showed statistically significant (p pollution controls for improved wastewater treatment plants and practices to reduce nutrients on farms and suburban lands, have reduced concentrations of nitrogen." But could this conclusion be pre-mature? I recently undertook a comparable analysis of long-term nitrate-N trends for a different group of watersheds (all located in the Chesapeake Bay watershed with long data records); this group includes nine watersheds that are predominantly (i.e., >75%) forested, plus five other Potomac River subwatersheds added for comparison. Based on comparable data and analytical methods to those used by CBP partners and USGS, 13 of the 14 sites-including both Potomac River stations (Chain Bridge at Washington DC and Hancock, Maryland)-showed statistically significant decreasing linear trends in annual flow-weighted nitrate-N concentration. Only one station-the heavily agricultural Upper Monocacy River-did not show a statistically significant (p RIM station could be entirely explained by commensurate improvements at the upstream (Hancock) station; in fact, no trend in nitrate-N concentration associated with the eastern portion of the basin was found (after subtracting out the influence of the upstream portion). Additional research is needed to understand why nitrogen retention by forested lands may be increasing and thus helping restore water quality throughout the Chesapeake Bay watershed. The results also have obvious implications for meeting local water quality goals as well as the basin-wide goal of the

  5. 76 FR 35398 - Scoria Mining Addition, Medicine Bow-Routt National Forests and Thunder Basin National Grassland...

    Science.gov (United States)

    2011-06-17

    ... authorize Thunder Basin Coal Company, LLC to expand the area of its existing scoria gravel pit development... statement (DEIS) is expected to be available by October 2011, and the final environmental impact statement... analysis and its findings and then document the final decision in a Record of Decision (ROD). The decision...

  6. Mapping forested wetlands in the Great Zhan River Basin through integrating optical, radar, and topographical data classification techniques.

    Science.gov (United States)

    Na, X D; Zang, S Y; Wu, C S; Li, W L

    2015-11-01

    Knowledge of the spatial extent of forested wetlands is essential to many studies including wetland functioning assessment, greenhouse gas flux estimation, and wildlife suitable habitat identification. For discriminating forested wetlands from their adjacent land cover types, researchers have resorted to image analysis techniques applied to numerous remotely sensed data. While with some success, there is still no consensus on the optimal approaches for mapping forested wetlands. To address this problem, we examined two machine learning approaches, random forest (RF) and K-nearest neighbor (KNN) algorithms, and applied these two approaches to the framework of pixel-based and object-based classifications. The RF and KNN algorithms were constructed using predictors derived from Landsat 8 imagery, Radarsat-2 advanced synthetic aperture radar (SAR), and topographical indices. The results show that the objected-based classifications performed better than per-pixel classifications using the same algorithm (RF) in terms of overall accuracy and the difference of their kappa coefficients are statistically significant (pwetlands based on the per-pixel classifications using the RF algorithm. As for the object-based image analysis, there were also statistically significant differences (pwetlands and omissions for agriculture land. This research proves that the object-based classification with RF using optical, radar, and topographical data improved the mapping accuracy of land covers and provided a feasible approach to discriminate the forested wetlands from the other land cover types in forestry area.

  7. High Resolution Modelling of the Congo River's Multi-Threaded Main Stem Hydraulics

    Science.gov (United States)

    Carr, A. B.; Trigg, M.; Tshimanga, R.; Neal, J. C.; Borman, D.; Smith, M. W.; Bola, G.; Kabuya, P.; Mushie, C. A.; Tschumbu, C. L.

    2017-12-01

    We present the results of a summer 2017 field campaign by members of the Congo River users Hydraulics and Morphology (CRuHM) project, and a subsequent reach-scale hydraulic modelling study on the Congo's main stem. Sonar bathymetry, ADCP transects, and water surface elevation data have been collected along the Congo's heavily multi-threaded middle reach, which exhibits complex in-channel hydraulic processes that are not well understood. To model the entire basin's hydrodynamics, these in-channel hydraulic processes must be parameterised since it is not computationally feasible to represent them explicitly. Furthermore, recent research suggests that relative to other large global rivers, in-channel flows on the Congo represent a relatively large proportion of total flow through the river-floodplain system. We therefore regard sufficient representation of in-channel hydraulic processes as a Congo River hydrodynamic research priority. To enable explicit representation of in-channel hydraulics, we develop a reach-scale (70 km), high resolution hydraulic model. Simulation of flow through individual channel threads provides new information on flow depths and velocities, and will be used to inform the parameterisation of a broader basin-scale hydrodynamic model. The basin-scale model will ultimately be used to investigate floodplain fluxes, flood wave attenuation, and the impact of future hydrological change scenarios on basin hydrodynamics. This presentation will focus on the methodology we use to develop a reach-scale bathymetric DEM. The bathymetry of only a small proportion of channel threads can realistically be captured, necessitating some estimation of the bathymetry of channels not surveyed. We explore different approaches to this bathymetry estimation, and the extent to which it influences hydraulic model predictions. The CRuHM project is a consortium comprising the Universities of Kinshasa, Rhodes, Dar es Salaam, Bristol, and Leeds, and is funded by Royal

  8. Soil and water losses in eucalyptus plantation and natural forest and determination of the USLE factors at a pilot sub-basin in Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Bárbara Pereira Christofaro Silva

    Full Text Available ABSTRACT Monitoring water erosion and the factors that control soil and water loss are essential for soil conservation planning. The objective of this study was to evaluate soil and water losses by water erosion under natural rainfall in eucalyptus plantations established in 2001 (EF2, and 2004 (EF1, native forest (NF and bare soil (BS, during the period of 2007 to 2012; and to determine the USLE factors: rain erosivity (R, erodibility (K of a Red Argisol and the cover-management factor (C for EF1, EF2 and NF at a pilot sub-basin, in Eldorado do Sul, RS, Brazil. The R factor was estimated by the EI30 index, using rainfall data from a gauging station located at the sub-basin. The soil and water losses were monitored in erosion plots, providing consistent data for the estimation of the K and C factors. The sub-basin presented an average erosivity of 4,228.52 MJ mm ha-1 h-1 yr-1. The average annual soil losses em EF1 and EF2 (0.81 e 0.12 Mg ha-1 year-1, respectively were below of the limit of tolerance, 12.9 Mg ha-1 year-1. The percentage values of water loss relating to the total rainfall decreased annually, approaching the values observed at the NF. From the 5th year on after the implantation of the eucalyptus systems, soil losses values were similar to the ones from NF. The erodibility of the Red Argisol was of 0.0026 Mg ha h ha-1 MJ-1mm-1 and the C factor presented values of 0.121, 0.016 and 0.015 for EF1, EF2 and NF, respectively.

  9. [Crimean-Congo hemorrhagic fever].

    Science.gov (United States)

    Saijo, Masayuki; Moriikawa, Shigeru; Kurane, Ichiro

    2004-12-01

    Crimean-Congo hemorrhagic fever (CCHF) is an acute infectious disease caused by CCHF virus (CCHFV), a member of the family Bunyaviridae, genus Nairovirus. The case fatality rate of CCHF ranges from 10-40%. Because CCHF is not present in Japan, many Japanese virologists and clinicians are not very familiar with this disease. However, there remains the possibility of an introduction of CCHFV or other hemorrhagic fever viruses into Japan from surrounding endemic areas. Development of diagnostic laboratory capacity for viral hemorrhagic fevers is necessary even in countries without these diseases. At the National Institute of Infectious Diseases, Tokyo, Japan, laboratory-based systems such as recombinant protein-based antibody detection, antigen-capture and pathological examination have been developed. In this review article, epidemiologic and clinical data on CCHF in the Xinjiang Uygur Autonomous Region, compiled through field investigations and diagnostic testing utilizing the aforementioned laboratory systems, are presented. CCHFV infections are closely associated with the environmental conditions, life styles, religion, occupation, and human economic activities. Based on these data, preventive measures for CCHFV infections are also discussed.

  10. Pequonnock River Basin, Bridgeport, Connecticut. Forest Lake Dam CT 00078. Phase I Inspection Report. National Dam Inspection Program.

    Science.gov (United States)

    1978-08-01

    Legislation for the protection of wet lands has come too late for this watershed and the remaining small wet lands, if retained, have little value...Ridge Mountains of Central Virginia, 11.55" in Westminister , Maryland and 13" in Steuben County, Pennsylvania. HYDRAULIC ANALYSIS LAKE FOREST Due to

  11. Managing for timber and biodiversity in the Congo Basin

    DEFF Research Database (Denmark)

    Nasi, Robert; Billand, Alain; van Vliet, Nathalie

    2012-01-01

    concessions) and analyze the existing issues and options for managing actively both timber and biodiversity with a special emphasis on wildlife and the role of certification. A few promising but yet ‘unfinished’ examples do exist in the region and we review these cases to draw lessons and recommendations. We...... contend however that true multiple-use could only be realized by expanding beyond boundaries of formal management units through new innovative land-use units, allowing a spatial cohabitation of the interests of local people, of conservation proponents and of extractive industries in the same management...

  12. Climate Change Adaptation Options for the Congo Basin Countries

    NARCIS (Netherlands)

    Garderen, van L.; Ludwig, F.

    2012-01-01

    During the last decades, the importance and seriousness of climate change and it’s impacts have become more and more understood. The climate is already changing and therefor adaptation to these changes need to be made. Central Africa needs to adapt to climate change just as much as the rest of the

  13. Status of forest onchocerciasis in the Lower Cross River basin, Nigeria: entomologic profile after five years of ivermectin intervention.

    Science.gov (United States)

    Opara, Kenneth N; Fagbemi, Olakunle B; Ekwe, Asuquo; Okenu, Daniel M N

    2005-08-01

    In the Lower Cross River basin in Nigeria, no pre-control entomologic profile of Onchocerca volvulus infection in the local Simulium damnosum population was available prior to the initiation of an ivermectin control program in 1995. A longitudinal entomologic study was therefore carried out over a 12-month period (January-December 2001) at the Agbokim waterfalls and Afi River, which are breeding sites of S. damnosum in the river basin. A total of 9,287 adult S. damnosum were caught on human bait; 9,048 (97.43%) were dissected, of which 313 (3.46%) were infected. Annual biting rates (ABRs) of 42,419 and 28,346 bites per persons per year were recorded at the Agbokim Waterfalls and Afi River, respectively. The annual transmission potential (ATP) was 419 infective larvae per person per year at the Agbokim Waterfalls and 427 at the Afi River. Monthly biting rate and monthly transmission potential varied significantly (P < 0.05) at the two sites. Transmission was highly seasonal from April to September, corresponding to the peak biting period of the vector. The high ATP and ABR values are a measure of the mesoendemicity of onchocerciasis in the river basin. There was a significant F(0).05 (1, 10) (P < 0.05) variation in the relative fly abundance from both sites. It was observed that human activities such as farming, fishing, timber cutting, and hunting are done in the early morning and late afternoon, which corresponds to the peak diurnal biting period of the vector. Changes in these practices and attitudes may markedly affect the disease intensity and transmission.

  14. Contributions to the herpetofauna of the Albertine Rift: Two new species of chameleon (Sauria: Chamaeleonidae) from an isolated montane forest, south eastern Democratic Republic of Congo.

    Science.gov (United States)

    Tilbury, Colin R; Tolley, Krystal A

    2015-01-13

    Two new species of chameleons from the genera Rhampholeon and Kinyongia are described from an isolated montane forest remnant situated toward the southern end of the Albertine Rift bordering Lake Tanganyika. The closest known localities of species from these genera are 200km and 400km to the north respectively, separated by large intervening tracts of lowland savannah and Brachystegia (Miombo) woodland - habitats not normally inhabited by species of these genera. Rhampholeon hattinghi sp. nov. and Kinyongia mulyai sp. nov. bear superficial resemblances to previously described species (Rh. boulengeri Steindachner and K. adolfifriderici  (Sternfeld)). Rhampholeon hattinghi sp. nov. has a relatively smooth supra-orbital ridge, deep axillary but absent inguinal mite pockets, prominent white spots on the base of the tail and a uniquely derived hemipenal morphology with billowing parasulcal evaginations. Like K. adolfifriderici, Kinyongia mulyai sp. nov. is devoid of a rostral appendage but differs in having a longer and narrower head, a higher upper labial scale count and by the absence of a dorsal crest in the male. To place these new chameleons within the context of their respective genera, Bayesian and maximum likelihood phylogenetic analyses were carried out utilising two mitochondrial (ND2 and 16S) and one nuclear marker (RAG1).  Both chameleons were found to have morphological features that distinguish them from other congeners. Based on phylogenetic analysis they are clearly separate evolutionary lineages and are described as new species. 

  15. Evolution and estimated age of the C5 Lukala carbonate-evaporite ramp complex in the Lower Congo region (Democratic Republic of Congo): New perspectives in Central Africa

    Science.gov (United States)

    Delpomdor, F.; Van Vliet, N.; Devleeschouwer, X.; Tack, L.; Préat, A.

    2018-01-01

    New detailed lithological, sedimentological, chemostratigraphic data were obtained from exploration drilling samples on the C5 carbonate-dominated formation of the Neoproterozoic Lukala Subgroup (former Schisto-Calcaire Subgroup) from the West Congo Belt (WCB) in the Democratic Republic of Congo. This formation records the last post-Marinoan sea-level events that occurred in the whole basin, followed by the development of the Araçuaï-West Congo Orogen between 630 and 560 Ma. The C5 Formation consists of back-reef lagoonal and peritidal/sabkha cycles of ∼2.0 m in thickness, that record a short-time marine regression, rapidly flooded by a marine transgression with deposition of organic-rich argillaceous carbonates or shales under dysoxia and anoxia conditions. These dysoxic/anoxic waters were rapidly followed by a regional-scale marine transgression, favouring mixing with well-oxygenated waters, and the development of benthic Tonian to Cambro-Ordovician Obruchevella parva-type 'seagrasses' in the nearshore zones of the lagoons. New δ13C and 87Sr/86Sr isotopic data in the C5 Formation of the Lukala Subgroup are used in the frame of a correlation with the Sete Lagoas Formation in Brazil. Relatively comparable negative to positive δ13C excursions point to marine flooding of the whole basin and allow extension of the debatable Late Ediacaran age of the uppermost Sete Lagoas and C5 formations. Sr isotope ;blind dating; failed due to low Sr concentration related to a dolomitization event close 540 Ma. Several tentative datings of the C5 Formation converge to a Late Ediacaran age ranging between 575 and 540 Ma. As the overlying Mpioka folded Subgroup, the C5 series suffered the Pan African deformation, dated at 566 ± 42 Ma. Unlike the previously generally accepted interpretation, our data suggests that the Mpioka Subgroup was deposited in the Early Cambrian.

  16. Democratic Republic of Congo Jobs Diagnostic

    OpenAIRE

    Aterido, Reyes; Gonzalez, Alvaro; Merotto, Dino; Petracco, Carly; Sanchez-Reaza, Javier

    2018-01-01

    The economy of the Democratic Republic of Congo is not creating sufficient jobs for its young and rapidly growing workforce. Although the Congolese economy has experienced fast growth and poverty has declined, further reducing poverty will require more dynamic job creation and continued reductions in fertility rates. The current youth bulge and potential demographic dividend will open a un...

  17. Crimean-Congo Hemorrhagic Fever, Sudan, 2008

    Centers for Disease Control (CDC) Podcasts

    This podcast describes the emergence of the first human cases of Crimean-Congo Hemorrhagic Fever in Sudan in 2008. CDC epidemiologist Dr. Stuart Nichol discusses how the disease was found in Sudan and how it spread in a hospital there.

  18. Climate and Hydrological Data Analysis for hydrological and solute transport modelling purposes in the Muriaé River basin, Atlantic Forest Biome, SE Brazil

    Science.gov (United States)

    Santos, Juliana; Künne, Annika; Kralisch, Sven; Fink, Manfred; Brenning, Alexander

    2016-04-01

    The Muriaé River basin in SE Brazil has been experiencing an increasing pressure on water resources, due to the population growth of the Rio de Janeiro urban area connected with the growth of the industrial and agricultural sector. This leads to water scarcity, riverine forest degradation, soil erosion and water quality problems among other impacts. Additionally the region has been suffering with seasonal precipitation variations leading to extreme events such as droughts, floods and landslides. Climate projections for the near future indicate a high inter-annual variability of rainfall with an increase in the frequency and intensity of heavy rainfall events combined with a statistically significant increase in the duration of dry periods and a reduced duration of wet periods. This may lead to increased soil erosion during the wet season, while the longer dry periods may reduce the vegetation cover, leaving the soil even more exposed and vulnerable to soil erosion. In consequence, it is crucial to understand how climate affects the interaction between the timing of extreme rainfall events, hydrological processes, vegetation growth, soil cover and soil erosion. In this context, physically-based hydrological modelling can contribute to a better understanding of spatial-temporal process dynamics in the Earth's system and support Integrated Water Resourses Management (IWRM) and adaptation strategies. The study area is the Muriaé river basin which has an area of approx. 8000 km² in Minas Gerais and Rio de Janeiro States. The basin is representative of a region of domain of hillslopes areas with the predominancy of pasture for livestock production. This study will present some of the relevant analyses which have been carried out on data (climate and streamflow) prior to using them for hydrological modelling, including consistency checks, homogeneity, pattern and statistical analyses, or annual and seasonal trends detection. Several inconsistencies on the raw data were

  19. Geological investigation of shaft mine in Devonian limestone in Kansas City, Missouri and other potentially dry excavated subsurface space in part of the Forest City Basin

    Energy Technology Data Exchange (ETDEWEB)

    Goebel, E.D.

    1977-10-01

    A high quality limestone is currently being mined from a deep shaft mine (1072 feet) in Middle Devonian rocks (Callaway) within the city limits of Kansas City, Missouri. About 15 acres of essentially dry space (room and pillar) with up to 14-foot ceilings have been developed. There are few natural joints observable in the rock within the mine. Some of these are periodically damp. More than 80% of the mine is dry. Saltwater from aquifers (Pennsylvanian) cut by the shaft accumulates behind the shaft at the pump station at 850 feet and at the bottom of the shaft (Devonian-Ordovician rocks). As long as the pumps lift the water to the surface, the mine can be kept relatively dry. Grouting of the aquifer's rocks in the shaft may seal off that source of water. The Burlington limestone of the Mississippian System is potentially mineable on the property now developed. The Burlington limestone, the Middle Devonian limestone, and the Kimmswick (Middle Ordovician) limestone are all potentially mineable by shaft mining in the northern part of Greater Kansas City and northward into the Forest City Basin.

  20. Abbreviated larval development of Macrobrachium inpa Kensley and Walker, 1982 (Crustacea: Decapoda: Palaemonidae from an Amazon Basin forest stream, Brazil, reared in the laboratory

    Directory of Open Access Journals (Sweden)

    Célio Magalhães

    Full Text Available Abstract This paper brings the description and illustrations of the abbreviated larval development of the Amazonian freshwater palaemonid shrimp, Macrobrachium inpa Kensley and Walker, 1982. The study was based on ovigerous females (mean total body length of 27.0 ± 1.64 mm collected in a small forest stream in the Reserva Florestal Ducke, near Manaus, Brazil, of which four released their larvae in the laboratory. The females carried 8 to 19 eliptical (2.39 ± 0.10 X 1.67 ± 0.08 mm, yolk-rich eggs. The larval period consists of three benthic, lecithotrophic larval stages, and lasts 10-11 days. The newly-hatched larvae bear very advanced morphological features such as antenna with several marginal plumose seta on scaphocerite and long, multi-articulated flagellum; fully developed, functional uniramous pereiopods 3-5 (walking legs and biramous pleopods. The morphology of the carapace, all appendages of the cephalothorax and pleon, and the tail fan are described in detail and illustrated. The larval form was considered to be a decapodid because of the benthic behavior and due to the fact that functional walking legs and pleopods are the main structures for displacement and propulsion. The larval development of M. inpa is compared with those of the so-called "continental" group of the caridean shrimps from the Amazon River basin.

  1. 3D stratigraphic modeling of the Congo turbidite system since 210 ka: an investigation of factors controlling sedimentation

    Science.gov (United States)

    Laurent, Dimitri; Picot, Marie; Marsset, Tania; Droz, Laurence; Rabineau, Marina; Granjeon, Didier; Molliex, Stéphane

    2017-04-01

    The geometry and internal functioning of turbidite systems are relatively well-constrained today. However, the respective role of autogenic (topographic compensation, dynamics of turbidity currents…) and allogenic factors (tectonics, sea-level, climate) governing their architectural evolution is still under debate. The geometry of the Quaternary Congo Fan is characterized by successive sedimentary prograding/retrograding cycles bounded by upfan avulsions, reflecting a periodic control of sedimentation (Picot et al., 2016). Multi-proxy studies revealed a strong interplay between autogenic control and climate forcing as evidenced by changes in fluvial sediment supplies consistent with arid and humid periods in the Congo River Basin. In the light of these results, the aim of this study is to investigate the relative impact of internal and external forcing factors controlling, both in time and space, the formation and evolution of depocenters of the Congo Deep-Sea Fan since 210 ka. This work represents the first attempt to model in 3D the stratigraphic architecture of the Congo turbidite system using DionisosFlow (IFP-EN), a diffusion process-based software. It allows the simulation of sediment transport and the 3D geometry reproduction of sedimentary units based on physical processes such as sea level changes, tectonics, sediment supply and transport. According to the modeling results, the role of topographic compensation in the deep-sea fan geometry is secondary compared to climate changes in the drainage basin. It appears that a periodic variation of sediment discharge and water flow is necessary to simulate the timing and volume of prograding/retrograding sedimentary cycles and more particularly the upfan avulsion events. The best-fit simulations show that the overriding factor for such changes corresponds to the expansion of the vegetation cover in the catchment basin associated to the Milankovitch cycle of precession which controlled the West African Monsoon

  2. Impacts of logging and hunting on western lowland gorilla (Gorilla gorilla gorilla populations and consequences for forest regeneration. A review

    Directory of Open Access Journals (Sweden)

    Haurez, B.

    2013-01-01

    Full Text Available Timber exploitation is rapidly expanding throughout the Congo Basin. Forest areas assigned to timber harvesting have sharply expanded over the decades and logging concessions now largely overlap with the range of western lowland gorilla (Gorilla gorilla gorilla Savage & Wyman, 1847. However this species, which is considered as critically endangered by IUCN, could play an essential role in maintaining the structure and composition of tropical rainforest notably through seed dispersal services. This is likely due to its frugivorous diet, high stomach capacity and ability to swallow seeds of variable sizes. Moreover gorillas have a long gut retention time of ingested food, travel long daily distances and deposit most ingested seeds in suitable habitats for plant development (such as logging gaps. Consequently, the preservation of the role of gorilla in forest regeneration is essential in the context of logged forest ecosystems. Timber harvesting has two major opposing impacts on gorilla populations: on the one hand, gorillas benefit from growth of herbaceous vegetation (e.g. Marantaceae and Zingiberaceae following forest canopy opening, as such herbs provide both staple food and nest-building materials; on the other hand, gorilla populations suffer with the rise in hunting associated with logging activity, especially with road network installation. Considering the potential negative knock-on effects of logging concessions on the ecological function of western lowland gorilla, the implementation of timber harvesting methods that preserve gorilla populations is a considerable challenge for forest sustainability, as well as for gorilla's conservation.

  3. Household determinants of bushmeat and eru (Gnetum africanum) harvesting for cash in the Democratic Republic of Congo

    DEFF Research Database (Denmark)

    Bakkegaard, Riyong Kim; Nielsen, Martin Reinhardt; Thorsen, Bo Jellesmark

    2017-01-01

    Peri-urban pressure on the Luki Biosphere Reserve in Bas-Congo, Democratic Republic of Congo, is fuelled by growing demand in urban markets coupled with easy access. With data from 175 randomly selected households, this paper examines factors that motivate households to collect two major forest....... Greater market distance being a female-headed household and greater age of household heads negatively affected selection into eru collection, reflecting characteristics of cash harvesting activities. Low education and more local knowledge characterised more successful outcome of eru collection, whereas...... of these activities in providing a pathway out of poverty and stress the needs for better integration of conservation and development policies....

  4. [Approach to sexuality in an AIDS context in Congo].

    Science.gov (United States)

    Courtois, R; Mullet, E; Malvy, D

    2001-01-01

    The pandemic due to the human immunodeficiency virus (HIV) is extensive in Sub-Saharan Africa and especially in Congo. Congo is a small country on the Atlantic coast and characterized by plentiful equatorial forests and low population density (essentially urban). In Congo, there is a high prevalence of HIV. The social and economic consequences of AIDS add to those of a recent civil war in 1997. There were fratricidal confrontations before and after this period. These confrontations have led to a massive exodus of the inhabitants of the capital, Brazzaville, to the forests and neighbouring cities, essentially towards Pointe-Noire. Pointe-Noire, chief place of the region of Kouilou, in the South of the country, is the second city of Congo and the economic Capital. It is undoubtedly for this reason that it has been globally saved. In this context, a sanitary policy of prevention of sexual risky behavior can appear as a challenge. While it supposes a better knowledge of the sexual activity of the young people, it cannot be dissociated from the analysis of the other factors. These factors can be of socio-economic political or cultural order. Thus the influence of cultural variables in the field of sexuality is certainly preponderant in African countries, where sexuality is taboo. Sexuality is a private matter (personal intimacy and the couple), but concerns also the family (in the sense of membership in an extended domestic group or in a system of relationship) in its aspects related to procreation and to the social field (power, alliances). Such individual behaviour can be lived as a questioning of the social order. In this article, the authors question the place of sexuality in Congo, particularly based on the work of anthropologists [2, 6, 7, 9]. Research in the field of sexuality at adolescence is rather recent in France and investigations that have been done in Congo these last ten years do not exist. Meetings and exchanges in 1998 with high-school pupils and

  5. Bushmeat consumption among rural and urban children from Province Orientale, Democratic Republic of Congo

    DEFF Research Database (Denmark)

    van Vliet, Nathalie; Nebesse, Casimir; Nasi, Robert

    2015-01-01

    of other meat (from the wild, such as fish and caterpillars, or from domestic sources, such as beef, chicken, pork, goat and mutton) among children from Province Orientale, Democratic Republic of Congo. Our results show that urban and rural households consume more meat from the wild than from domestic...... monkeys), probably because rural households tend to consume the less marketable species or the smaller animals. We show that despite the tendency towards more urbanized population profiles and increased livelihood opportunities away from forest and farms, wildlife harvest remains a critical component...

  6. La violencia sexual en Kivu Sur, Congo

    OpenAIRE

    Rodríguez, Claudia

    2007-01-01

    Abordar la violencia sexual y por motivos de género en la República Democrática del Congo (RDC) requerirá más recursos y coordinación. Un sistema judicial débil o inexistente disuade a las sobrevivientes de denunciar a sus agresores. El número de agresiones sigue aumentando y los perpetradores quedan impunes.

  7. Crimean-Congo Hemorrhagic Fever, Sudan, 2008

    Centers for Disease Control (CDC) Podcasts

    2010-04-15

    This podcast describes the emergence of the first human cases of Crimean-Congo Hemorrhagic Fever in Sudan in 2008. CDC epidemiologist Dr. Stuart Nichol discusses how the disease was found in Sudan and how it spread in a hospital there.  Created: 4/15/2010 by National Center for Emerging and Zoonotic Infections (proposed).   Date Released: 4/15/2010.

  8. Distribution and Numbers of Pygmies in Central African Forests.

    Directory of Open Access Journals (Sweden)

    Jesús Olivero

    Full Text Available Pygmy populations occupy a vast territory extending west-to-east along the central African belt from the Congo Basin to Lake Victoria. However, their numbers and actual distribution is not known precisely. Here, we undertake this task by using locational data and population sizes for an unprecedented number of known Pygmy camps and settlements (n = 654 in five of the nine countries where currently distributed. With these data we develop spatial distribution models based on the favourability function, which distinguish areas with favourable environmental conditions from those less suitable for Pygmy presence. Highly favourable areas were significantly explained by presence of tropical forests, and by lower human pressure variables. For documented Pygmy settlements, we use the relationship between observed population sizes and predicted favourability values to estimate the total Pygmy population throughout Central Africa. We estimate that around 920,000 Pygmies (over 60% in DRC is possible within favourable forest areas in Central Africa. We argue that fragmentation of the existing Pygmy populations, alongside pressure from extractive industries and sometimes conflict with conservation areas, endanger their future. There is an urgent need to inform policies that can mitigate against future external threats to these indigenous peoples' culture and lifestyles.

  9. A VRML-Based Data Portal: Hydrology of the Hubbard Brook Experimental Forest and Mirror Lake Sub-Basin

    Science.gov (United States)

    Becker, M. W.; Bursik, M. I.; Schuetz, J. W.

    2001-05-01

    The Hubbard Brook Experimental Forest (HBEF) of Central New Hampshire has been a focal point for collaborative hydrologic research for over 40 years. A tremendous amount of data from this area is available through the internet and other sources, but is not organized in a manner that facilitates teaching of hydrologic concepts. The Mirror Lake Watershed Interactive Teaching Database is making hydrologic data from the HBEF and associated interactive problem sets available to upper-level and post-graduate university students through a web-based resource. Hydrologic data are offered via a three-dimensional VRML (Virtual Reality Modeling Language) interface, that facilitates viewing and retrieval in a spatially meaningful manner. Available data are mapped onto a topographic base, and hot spots representing data collection points (e.g. weirs) lead to time-series displays (e.g. hydrographs) that provide a temporal link to the spatially organized data. Associated instructional exercises are designed to increase understanding of both hydrologic data and hydrologic methods. A pedagogical module concerning numerical ground-water modeling will be presented as an example. Numerical modeling of ground-water flow involves choosing the combination of hydrogeologic parameters (e.g. hydraulic conductivity, recharge) that cause model-predicted heads to best match measured heads in the aquifer. Choosing the right combination of parameters requires careful judgment based upon knowledge of the hydrogeologic system and the physics of ground-water flow. Unfortunately, students often get caught up in the technical aspects and lose sight of the fundamentals when working with real ground-water software. This module provides exercises in which a student chooses model parameters and immediately sees the predicted results as a 3-D VRML object. VRML objects are based upon actual Modflow model results corresponding to the range of model input parameters available to the student. This way, the

  10. 5. Basin assessment and watershed analysis

    Science.gov (United States)

    Leslie M. Reid; Robert R. Ziemer

    1994-01-01

    Abstract - Basin assessment is an important component of the President's Forest Plan, yet it has received little attention. Basin assessments are intended both to guide watershed analyses by specifying types of issues and interactions that need to be understood, and, eventually, to integrate the results of watershed analyses occurring within a river basin....

  11. Internet Backbone in the Democratic Republic of Congo : Feasibility ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Internet Backbone in the Democratic Republic of Congo : Feasibility Study and Advocacy. During 7-10 February 2005, representatives of five francophone African countries (Cameroon, Morocco, Niger, Sénégal, and the Democratic Republic of Congo - DRC) met to consider ways and means of galvanizing the appropriation ...

  12. Variations des apports de litière et d'éléments minéraux dans les plantations de limba (Terminalia superba au Congo

    Directory of Open Access Journals (Sweden)

    Kokolo, A.

    2005-01-01

    Full Text Available Variations in Litter Production and Nutrient Supply in Plantations of Limba (Terminalia superba in Congo. A study was carried out in a chronosequence of Terminalia superba (7, 12 and 48 years and a nearby natural forest. The results show that the peaks of litterfall take place in rainy season contrary to the majority of the forest formations of the humid tropical zone. The return of nutrients to the soil via the leaf litter is higher in plantations than in forest. The calcium released from the leaf litter was up to 175 kg.ha-1.year1. The values obtained indicate a moderate nutrient use efficiency by Terminalia superba.

  13. Population structure and reproduction of Deuterodon langei travassos, 1957 (Teleostei, Characidae in a neotropical stream basin from the Atlantic Forest, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Jean Ricardo Simões Vitule

    2008-12-01

    Full Text Available Aspects of the biology of D. langei were studied at different sites along a longitudinal gradient formed by the Ribeirão stream basin, a Neotropical stream of the Atlantic Forest, southern Brazil. Differences were observed in population structure and reproduction along the longitudinal gradient and during the study period. Juvenile fishes occurred in high abundance, mainly in the downstream site after the rainy months. Adults occurred mainly in the intermediate and upstream sites. During their life cycle, adults optimise their reproductive strategy by concentrating the reproductive period with total spawn in a short time interval before summer rains dragged the juvenile, larval forms and/or eggs downstream. The downstream site was characterized by a wide range of microhabitats (ex. submerged grass and shallow flooded area. Thus, the species used different portions of the basin in distinct stages of its life, being ecologically adapted to variation patterns in its temporal and physical environments.Aspectos da biologia de D. langei foram estudados em diferentes locais da bacia do rio Ribeirão, um riacho litorâneo da Floresta Atlântica do sudeste do Brasil. Foram observadas diferenças na estrutura da população e na reprodução, ao longo do gradiente longitudinal da bacia e do período de estudo. Os peixes juvenis ocorreram em grande abundância, principalmente no trecho a jusante da bacia, após os meses mais chuvosos. Adultos ocorreram principalmente nos trechos intermediários e a montante. Não houve diferença significativa na relação sexual entre os locais amostrados, estações do ano, meses e classes de comprimento. O comprimento médio de primeira maturação (L50 foi o mesmo para machos e fêmeas, entre 6,1 e 7,0 cm de comprimento total (Lt. O período reprodutivo foi curto (entre o final da primavera e início do verão, antes dos meses mais chuvosos, com desova total. O Índice de Atividade Reprodutiva (IAR indicou que D

  14. Interceptação das chuvas em um fragmento de floresta da Mata Atlântica na Bacia do Prata, Recife, PE Rainfall interception in an Atlantic Forest fragment in the Prata Basin, Recife, PE

    Directory of Open Access Journals (Sweden)

    Albert Einstein Spindola Saraiva de Moura

    2009-06-01

    Full Text Available A mata de Dois Irmãos é uma das poucas áreas remanescentes da Floresta Atlântica no Estado de Pernambuco. Nela estão inseridos os açudes do Meio, do Prata e Dois Irmãos que compõem a bacia hidrográfica do Prata. Este trabalho teve como objetivo estudar a partição das chuvas em um fragmento de Floresta Atlântica na Bacia do Prata em Recife, PE. Para obtenção dos dados de precipitação sob florestas, foram instalados 24 interceptômetros e selecionadas 20 árvores do estrato superior, e 10 árvores do sub-bosque foram escolhidas para obter os dados de escoamento pelo tronco. Encontraram-se perdas por interceptação de 208,3 mm, precipitação efetiva de 1.431,7 mm, precipitação interna de 1.392,4 mm, escoamento pelo tronco das árvores do estrato superior de 6,6 mm e escoamento pelo sub-bosque de 32,8 mm, correspondendo a 12,7%, 87,3%, 84,9%, 0,4% e 2%, respectivamente, do total precipitado de 1.464 mm.The Dois Irmãos forest is one of the few remaining areas of the Atlantic Forest in the State of Pernambuco. The dams of Meio, Prata and Dois Irmãos, which belong to the Prata Basin, are in it. The objective of this work was to study the rainfall partitioning in a fragment of the Atlantic forest in the Prata basin, in Recife, PE. 24 raingouges were installed in the interior of the forest to measure the throughfall and 20 trees of superior extract and 10 of the sub-forest were selected to determine the stemflow. The results showed values of loss interception of 208,3 mm, net precipitation of 1431,7 mm, throughfall of 1392,4 mm, stemflow by superior stratum of 6,6 mm and stemflow by sub-forest of 32,8 mm, corresponding to 12,7%, 87,3%, 84,9%, 0,4% and 2%, respectively.

  15. Influence of biomass burning emissions on precipitation chemistry in the equatorial forests of Africa

    International Nuclear Information System (INIS)

    Lacaux, J.P.; Lefeivre, B.; Delmas, R.A.; Cros, B.; Andreae, M.O.

    1991-01-01

    As part of the DESCAFE program (Dynamics and Chemistry of the Atmosphere in Equatorial Forest), measurements of precipitation chemistry were made at two sampling sites of the equatorial forest in the Republic of Congo. The measurements were made in order to identify and compare atmospheric sources of gases and particles (mainly biogenic sources and emissions from burning vegetation)

  16. Unveiling soil degradation and desertification risk in the Mediterranean basin: a data mining analysis of the relationships between biophysical and socioeconomic factors in agro-forest landscapes

    NARCIS (Netherlands)

    Salvati, L.; Kosmas, C.; Kairis, O.; Karavitis, C.; Hessel, R.; Ritsema, C.J.

    2015-01-01

    Soil degradation and desertification processes in the Mediterranean basin reflect the interplay between environmental and socioeconomic drivers. An approach to evaluate comparatively the multiple relationships between biophysical variables and socioeconomic factors is illustrated in the present

  17. Análise Multitemporal da Cobertura Florestal da Microbacia do Arroio Grande, Santa Maria, RS Multitemporal Analysis of Forest Cover in the Arroio Grande Small Hydrological Basin, Santa Maria, RS

    Directory of Open Access Journals (Sweden)

    Joel Juliano Kleinpaul

    2011-03-01

    Full Text Available

    Este trabalho teve como objetivo realizar uma análise multitemporal da cobertura florestal da microbacia do Arroio Grande, Santa Maria, RS. Foram utilizadas quatro imagens de satélite: LANDSAT 5 (1987, LANDSAT 5 (1995, LANDSAT 7 (2002 e CBERS 2 (2005. As imagens foram classificadas empregando-se o algoritmo Bhattacharya. Após a classificação das imagens, foi realizado o cruzamento dos mapas temáticos. Como resultado, obteve-se mapas com os seguintes usos da terra: cobertura florestal, regeneração e desmatamento, ou seja, as florestas que permaneceram inalteradas de uma época para outra, as que regeneraram e as que foram desmatadas. Para um período de 18 anos, a cobertura florestal aumentou 10,24% na área da microbacia, passando de 14.135,42 ha (40,01% em 1987 para 17.752,20 ha (50,25% em 2005. Isto ocorreu devido à entrada em vigor do Código Florestal Estadual, à conscientização dosproprietários rurais e à implantação em maiorescala de povoamentos de espécies exóticas no estado. 
    This work aims to carry out a multitemporal analysis of the forest cover of Arroio Grande small hydrological basin located in Santa Maria, RS, Brazil. Four satellite images were used: LANDSAT 5 (1987, LANDSAT 5 (1995, LANDSAT 7 (2002 and CBERS 2 (2005. The images were classified according to the Bhattacharya algorithm. After the classification of such images, the crossing of the thematic maps was accomplished. Maps with different land uses were obtained: unaffected forest cover, regeneration and deforestation for the period 1987 – 2005. During 18 years, the forest cover increased 10,24% in the basin area, changing from 14.135,42 ha (40,01% in 1987 to 17.752,20 ha (50,25% in 2005. This happened because the State Forest Law has become effective as well as the rural owners’ consciousness and also due to increment of exotic forest plantations in the State. 

  18. Accounting for violence in Eastern Congo: Young people's ...

    African Journals Online (AJOL)

    In these accounts, the voices of young people have been largely absent. Although ... in eastern Congo from September to December 2009 as part of the author's doctoral ..... More rarely, young Congolese recognised the contribution made by ...

  19. Decolorisation of Congo Red by Aeromonas hydrophila Under Microaerophilic Conditions

    International Nuclear Information System (INIS)

    El Gizawy, S.; Refae, R.A.; Abd El Kareem, H.; Gomaa, O.M.; Hamed, H.

    2009-01-01

    Among 22 local bacterial isolates, Aeromonas hydrophila isolated from Bolti fish showed a remarkable ability to decolorize congo red under microaerophilic conditions (98.8% in 48 hrs) without prior adaptation. The bacterium had the ability to grow and decolorized high concentrations of congo red which varied from 50 to 1000 mg/l , the decolorisation was irrelevant to bacterial growth. The strain was capable of decolorizing congo red under a wide range of temperatures (20-40 degree C), ph (3-8), NaCl (0-200 mg/l) and also had the ability to decolorized mono, di and poly azo dyes. This bacterium is notable in its ability to decolorized the diazo congo red under extreme conditions of temperature, ph, salinity and high dye concentrations which makes it suitable for decolorisation under extreme industrial conditions

  20. The Congo crisis, the United Nations, and Zimbabwean nationalism ...

    African Journals Online (AJOL)

    United Nations moved swiftly in response to Lumumba's immediate request for assistance .... of apathy towards the white man in Africa and a strong desire to rid .... such actions would legitimatise the intervention of the Congo government in.

  1. Complex conflict in the Democratic Republic of the Congo: Good ...

    African Journals Online (AJOL)

    ... identifi ed business ethics as a way to mitigate the destructive commercial practices that ... Ethical business initiatives have peacebuilding potential; however, the ... of the Congo (DRC) and its surrounding areas by purchasing minerals that fi ...

  2. Rewriting the Landform History of One of Africa's Three Largest Basins

    Science.gov (United States)

    Wilkinson, Justin

    2014-01-01

    The Kalahari Basin in southern Africa - one of the largest basins in Africa, along with the Congo and Chad basins - has attracted attention since David Livingstone traveled through the area in the 1840s. It is a semiarid desert with a large freshwater swampland known as the Okavango Swamp (150 km radius). This prominent megafan (a fan with radii >100 km), with its fingers of dark green forests projecting into the dun colors of the dunes of the Kalahari semi-desert, has been well photographed by astronauts over the years. The study area in the northern Kalahari basin is centered on the Okavango megafan of northwest Botswana, whose swampland has become well known as an African wildlife preserve of importance to biology and tourism alike. The Okavango River is unusual because it has deposited not one but two megafans along its course: the Okavango megafan and the Cubango megafan. The Okavango megafan is one of only three well-known megafans in Africa. Megafans on Earth were once thought to be rare, but recent research has documented 68 in Africa alone. Eleven megafans, plus three more candidates, have been documented in the area immediately surrounding the Okavango feature. These 11 megafans occupy the flattest and smoothest terrains adjacent to the neighboring upland and stand out as the darkest areas in the roughness map of the area. Megafan terrains occupy at least 200,000 sq km of the study area. The roughness map shown is based on an algorithm used first on Mars to quantify topographic roughness. Research of Earth's flattest terrains is just beginning with the aid of such maps, and it appears that these terrains are analogous to the flattest regions of Mars. Implications: 1. The variability in depositional style in each subbasin may apply Africa-wide: rift megafan length is dominated by rift width, whereas Owambo subbasin megafans are probably controlled by upland basin size; Zambezi subbasin megafans appear more like foreland basin types, with the position of

  3. Mapping Water Level Dynamics over Central Congo River Using PALSAR Images, Envisat Altimetry, and Landsat NDVI Data

    Science.gov (United States)

    Kim, D.; Lee, H.; Jung, H. C.; Beighley, E.; Laraque, A.; Tshimanga, R.; Alsdorf, D. E.

    2016-12-01

    Rivers and wetlands are very important for ecological habitats, and it plays a key role in providing a source of greenhouse gases (CO2 and CH4). The floodplains ecosystems depend on the process between the vegetation and flood characteristics. The water level is a prerequisite to an understanding of terrestrial water storage and discharge. Despite the lack of in situ data over the Congo Basin, which is the world's third largest in size ( 3.7 million km2), and second only to the Amazon River in discharge ( 40,500 m3 s-1 annual average between 1902 and 2015 in the main Brazzaville-Kinshasa gauging station), the surface water level dynamics in the wetlands have been successfully estimated using satellite altimetry, backscattering coefficients (σ0) from Synthetic Aperture Radar (SAR) images and, interferometric SAR technique. However, the water level estimation of the Congo River remains poorly quantified due to the sparse orbital spacing of radar altimeters. Hence, we essentially have limited information only over the sparsely distributed the so-called "virtual stations". The backscattering coefficients from SAR images have been successfully used to distinguish different vegetation types, to monitor flood conditions, and to access soil moistures over the wetlands. However, σ0 has not been used to measure the water level changes over the open river because of very week return signal due to specular scattering. In this study, we have discovered that changes in σ0 over the Congo River occur mainly due to the water level changes in the river with the existence of the water plants (macrophytes, emergent plants, and submersed plant), depending on the rising and falling stage inside the depression of the "Cuvette Centrale". We expand the finding into generating the multi-temporal water level maps over the Congo River using PALSAR σ0, Envisat altimetry, and Landsat Normalized Difference Vegetation Index (NDVI) data. We also present preliminary estimates of the river

  4. Mycoremediation of congo red dye by filamentous fungi.

    Science.gov (United States)

    Bhattacharya, Sourav; Das, Arijit; G, Mangai; K, Vignesh; J, Sangeetha

    2011-10-01

    Azo, anthroquinone and triphenylmethane dyes are the major classes of synthetic colourants, which are difficult to degrade and have received considerable attention. Congo red, a diazo dye, is considered as a xenobiotic compound, and is recalcitrant to biodegradative processes. Nevertheless, during the last few years it has been demonstrated that several fungi, under certain environmental conditions, are able to transfer azo dyes to non toxic products using laccases. The aim of this work was to study the factors influencing mycoremediation of Congo red. Several basidiomycetes and deuteromycetes species were tested for the decolourisation of Congo red (0.05 g/l) in a semi synthetic broth at static and shaking conditions. Poor decolourisation was observed when the dye acted as the sole source of nitrogen, whereas semi synthetic broth supplemented with fertilizer resulted in better decolourisation. Decolourisation of Congo red was checked in the presence of salts of heavy metals such as mercuric chloride, lead acetate and zinc sulphate. Decolourisation parameters such as temperature, pH, and rpm were optimized and the decolourisation obtained at optimized conditions varied between 29.25- 97.28% at static condition and 82.1- 100% at shaking condition. Sodium dodecyl sulphate polyacrylamide gel electrophoretic analysis revealed bands with molecular weights ranging between 66.5 to 71 kDa, a characteristic of the fungal laccases. High efficiency decolourisation of Congo red makes these fungal forms a promising choice in biological treatment of waste water containing Congo red.

  5. Mycoremediation of Congo red dye by filamentous fungi

    Directory of Open Access Journals (Sweden)

    Sourav Bhattacharya

    2011-12-01

    Full Text Available Azo, anthroquinone and triphenylmethane dyes are the major classes of synthetic colourants, which are difficult to degrade and have received considerable attention. Congo red, a diazo dye, is considered as a xenobiotic compound, and is recalcitrant to biodegradative processes. Nevertheless, during the last few years it has been demonstrated that several fungi, under certain environmental conditions, are able to transfer azo dyes to non toxic products using laccases. The aim of this work was to study the factors influencing mycoremediation of Congo red. Several basidiomycetes and deuteromycetes species were tested for the decolourisation of Congo red (0.05 g/l in a semi synthetic broth at static and shaking conditions. Poor decolourisation was observed when the dye acted as the sole source of nitrogen, whereas semi synthetic broth supplemented with fertilizer resulted in better decolourisation. Decolourisation of Congo red was checked in the presence of salts of heavy metals such as mercuric chloride, lead acetate and zinc sulphate. Decolourisation parameters such as temperature, pH, and rpm were optimized and the decolourisation obtained at optimized conditions varied between 29.25- 97.28% at static condition and 82.1- 100% at shaking condition. Sodium dodecyl sulphate polyacrylamide gel electrophoretic analysis revealed bands with molecular weights ranging between 66.5 to 71 kDa, a characteristic of the fungal laccases. High efficiency decolourisation of Congo red makes these fungal forms a promising choice in biological treatment of waste water containing Congo red.

  6. Congo red and protein aggregation in neurodegenerative diseases.

    Science.gov (United States)

    Frid, Petrea; Anisimov, Sergey V; Popovic, Natalija

    2007-01-01

    Congo red is a commonly used histological dye for amyloid detection. The specificity of this staining results from Congo red's affinity for binding to fibril proteins enriched in beta-sheet conformation. Unexpectedly, recent investigations indicate that the dye also possesses the capacity to interfere with processes of protein misfolding and aggregation, stabilizing native protein monomers or partially folded intermediates, while reducing concentration of more toxic protein oligomers. Inhibitory effects of Congo red upon amyloid toxicity may also range from blockade of channel formation and interference with glycosaminoglycans binding or immune functions, to the modulation of gene expression. Particularly, Congo red exhibits ameliorative effect in models of neurodegenerative disorders, such as Alzheimer's, Parkinson's, Huntington's and prion diseases. Another interesting application of Congo red analogues is the development of imaging probes. Based on their small molecular size and penetrability through blood-brain barrier, Congo red congeners can be used for both antemortem and in vivo visualization and quantification of brain amyloids. Therefore, understanding mechanisms involved in dye-amyloidal fibril binding and inhibition of aggregation will provide instructive guides for the design of future compounds, potentially useful for monitoring and treating neurodegenerative diseases.

  7. The influence of pine forests of different ages on the biological activity of layland soils in the middle Angara River basin

    Science.gov (United States)

    Sorokina, O. A.; Sorokin, N. D.

    2007-05-01

    The influence of pine forests of different ages (from 25 to 85 years) restoring on old plow land soils is reflected in the biological processes proceeding in them. The drastic decrease in the absolute and relative number of actinomycetes, along with an increase of the fungal population in the microbial complexes of the soils (within the whole profiles), indicates that the microbocenoses acquire “forest” properties. In the soils under the younger pine forests, the processes of microbiological mineralization and specific respiration activity are more active than in the soils under the older pine forests. With the age of the pine forests, the soil profiles become more differentiated according to the eluvial-illuvial type.

  8. Ecologic Features of Plague Outbreak Areas, Democratic Republic of the Congo, 2004–2014

    Science.gov (United States)

    Shako, Jean-Christophe; Gaudart, Jean; Sudre, Bertrand; Ilunga, Benoit Kebela; Shamamba, Stomy Karhemere Bi; Diatta, Georges; Davoust, Bernard; Tamfum, Jean-Jacques Muyembe; Piarroux, Renaud; Piarroux, Martine

    2018-01-01

    During 2004–2014, the Democratic Republic of the Congo (DRC) declared 54% of plague cases worldwide. Using national data, we characterized the epidemiology of human plague in DRC for this period. All 4,630 suspected human plague cases and 349 deaths recorded in DRC came from Orientale Province. Pneumonic plague cases (8.8% of total) occurred during 2 major outbreaks in mining camps in the equatorial forest, and some limited outbreaks occurred in the Ituri highlands. Epidemics originated in 5 health zones clustered in Ituri, where sporadic bubonic cases were recorded throughout every year. Classification and regression tree characterized this cluster by the dominance of ecosystem 40 (mountain tropical climate). In conclusion, a small, stable, endemic focus of plague in the highlands of the Ituri tropical region persisted, acting as a source of outbreaks in DRC. PMID:29350136

  9. Dorstenia luamensis (Moraceae, a new species from eastern Democratic Republic of Congo

    Directory of Open Access Journals (Sweden)

    Miguel Leal

    2014-10-01

    Full Text Available A new species of Dorstenia L. (Moraceae, D. luamensis M.E.Leal, is described from the Luama Wildlife Reserve, west of Lake Tanganyika and north of the town of Kalemie in the eastern part of the Democratic Republic of Congo (DRC. This species is endemic to the region and differs from any of the other species by its fernlike lithophytic habit and lack of latex. A description and illustration of this species is presented here. Dorstenia luamensis M.E.Leal inhabits moist and shady vertical rock faces close to small waterfalls in the forest; the species is distributed in small populations within the type locality, and merits the conservation status of endangered (EN.

  10. Spatiotemporal patterns of tropical deforestation and forest degradation in response to the operation of the Tucuruí hydroelectricdam in the Amazon basin

    NARCIS (Netherlands)

    Chen, Gang; Powers, Ryan P.; Carvalho, de Luis M.T.; Mora, Brice

    2015-01-01

    The planned construction of hundreds of hydroelectric dams in the Amazon basin has the potential to provide invaluable 'clean' energy resources for aiding in securing future regional energy needs and continued economic growth. These mega-structures, however, directly and indirectly interfere with

  11. Coarse-scale restoration planning and design in Interior Columbia River Basin ecosystems: An example for restoring declining whitebark pine forests

    Science.gov (United States)

    Robert E. Keane; James P. Menakis; Wendel J. Hann

    1996-01-01

    During the last 2 years, many people from numerous government agencies and private institutions compiled a scientific assessment of the natural and human resources of the Interior Columbia River Basin (Jensen and Bourgeron 1993). This assessment is meant to guide the development of a coarse-scale Environmental Impact Statement for all 82 million hectares comprising the...

  12. Improving erosion modeling on forest roads in the Lake Tahoe Basin: Small plot rainfall simulations to determine saturated hydraulic conductivity and interrill erodibility

    Science.gov (United States)

    N. S. Copeland; R. B. Foltz

    2009-01-01

    Lake Tahoe is renowned for its beauty and exceptionally clear water. The Tahoe basin economy is dependent upon the protection of this beauty and the continued availability of recreational opportunities in the area; however, scientists estimate that the continued increase in fine sediment and nutrient transport to the lake threatens to diminish this clarity in as little...

  13. A Case Study of the Densu Basin, Ghana

    African Journals Online (AJOL)

    komla

    and middle sections of the basin are covered with semi-deciduous forest with a lush growth of thick and tall trees. ... and scrub forest vegetation with only few isolated trees. There are ... which underlie the south-eastern part of the basin and the area south of Weija to the estuary. The rocks of ...... Association, Washington, D.C.

  14. Radiation degradation of Congo Red in aqueous solution

    International Nuclear Information System (INIS)

    Ma Hongjuan; Wang Min; Yang Ruiyuan; Wang Wenfeng; Shen Zhongqun; Yao Side

    2006-01-01

    About one-half of the dyes used in textile industry are azo dyes, and as a consequence a lot of azo dyes are released into the environment with industrial wastewater. Because of complex structures of the dyes, biological, physical and chemical treatments of dye effluents are inefficient. In this study, radiation degradation of Congo Red in aqueous solutions was investigated in different reaction systems. Both pulsed radiolysis and laser flash photolysis experiments were carried out for better understandings of degradation mechanisms involved in the treatments. Congo Red solutions saturated by air, N 2 O, O 2 , N 2 O or N 2 and added with tert-butanol were irradiated to 0-14.8 kGy. The absorption spectra, degradation efficiency, TOC (total organic carbon) removal and pH changes of the solutions were investigated. The main radiolytic products from Congo Red samples irradiated in steady-state were determined by HPLC-MS. And probable reaction mechanisms were proposed. Effects of primary species from water radiolysis, such as e aq - , . OH and . O 2 . /HO 2 . on the degradation behavior of the dye were discussed. Below 5 kGy in γ-rays irradiation, the bleaching efficiency of Congo Red was (N 2 +tert-butanol) >O 2 >air>N 2 O>N 2 . Complete degradation of Congo Red was observed at 4.0, 5.5 and 10.2 kGy irradiation of the aqueous solutions saturated by N 2 with tert-butanol added, O 2 and N 2 O, respectively. With just oxidative or reductive species, highly conjugated part of Congo Red molecules could be destroyed. While oxidative species produced from water radiolysis could oxidize the Congo Red more effectively, making the dye to break into fatty acids and CO 2 finally. In the solution saturated with N 2 and air, the primary active species were both of oxidative and reductive and the highly conjugated part of Congo Red molecules could not be destroyed completely up to 14.8 kGy of γ-ray irradiation. It was more difficult to achieve high TOC removal in comparison with

  15. Groundwater Quality of Southeastern Brazzaville, Congo

    Directory of Open Access Journals (Sweden)

    Matini Laurent

    2010-01-01

    Full Text Available The groundwater in southeastern Brazzaville (Congo was analyzed for their fluoride contents and others related parameters in rainy season. The fluoride contents in water samples (wells and spring can be gather in three classes in the study area: low, optimal, high. Fluoride concentration in water samples presents a low significant correlation with Ca2+. This suggests that fluoride in the groundwater come from fluoride-bearing minerals such as CaF2 (fluorite. Maps were drawn to show the geographical distribution of EC, Ca2+, Mg2+and F-. Factor analysis and cluster analysis were applied to the dataset. Factor analysis resulted in four factors explained 76.90% of the total groundwater quality variance. Factor 1 (hardness of the groundwater includes total hardness, the concentration of K+, Ca2+ and pH. Factor 2 (low mineralization of the groundwater includes concentrations of TDS, Cl--, SO42+ and EC. Factor 3 (anthropogenic activities with the impact of agricultural fertilizers, farming activities, domestic wastewater, septic tanks includes concentrations of Na+ and NO3-. Factor 4 (weathering of calcium minerals includes concentrations of F-. For cluster analysis, Ward’s method and the Euclidean distance were used. The findings of the cluster analysis are presented in the form of dendrogram of the well water sites (cases. The discriminating parameters between clusters have been highlighted from the Student test. In majority, they are in accordance with those highlighted by factor analysis.

  16. Congo crimean hemorrhagic fever in balochistan

    International Nuclear Information System (INIS)

    Durrani, A.B.; Shaikh, M.; Khan, Z.

    2007-01-01

    To observe the pattern and mortality of Congo-Crimean Hemorrhagic Fever (CCHF) in Balochistan. Two hundred and twenty-six febrile patients with bleeding of sudden onset, with initial signs and symptoms including headache, high fever, back pain, joint pain, stomach pain, vomiting, red eyes, flushed face, red throat and petechiae on the palate of both sexes were screened for CCHF over a period of 10 years. Clinical criteria for initial diagnosis directed the subsequent diagnostic work-up. The ages of these patients ranged from 7 years to 74 years. Sixty-three percent of these patients were positive for CCHF. Males were 68% of the total patients. Over the years, CCHF showed a gradual increase ranging from 43% to 80%. Total mortality was 15%, all being secondary cases. Death was not observed in primary CCHF cases. In this study, suspicion of viral hemorrhagic fever was raised in 62% cases at the time of admission and the patients were immediately isolated, noninvasive procedures were instigated and barrier nursing was implemented. None of the family and hospital staff members who had close contact with the patient became ill, while those who were not suspected initially (38%) infected the health care workers and the family members. Although CCHF is rare, this study stresses the need for proper health facilities in Pakistan and to include VHF (viral hemorrhagic fevers) in the differential diagnosis of unexplained fever with hemorrhagic tendencies of sudden onset. (author)

  17. Forest Microclimate Characteristics Review

    Science.gov (United States)

    2014-09-01

    1123–32. This study area was located in the coastal mountain range of the Serra do Palmital, Saquarema, in the State of Rio de Janeiro , Brazil...the Atlantic forest in Rio de Janeiro . The objective of the study was to reveal whether forest fragmentation produces biotic and abiotic differences...Roanoke River Basin, North Carolina North Carolina percentage cover of individual species, percentage cover of exotic species, species richness

  18. Variation in tree mortality and regeneration affect forest carbon recovery following fuel treatments and wildfire in the Lake Tahoe Basin, California, USA

    Directory of Open Access Journals (Sweden)

    Carlson Chris H

    2012-06-01

    Full Text Available Abstract Background Forest fuel treatments have been proposed as tools to stabilize carbon stocks in fire-prone forests in the Western U.S.A. Although fuel treatments such as thinning and burning are known to immediately reduce forest carbon stocks, there are suggestions that these losses may be paid back over the long-term if treatments sufficiently reduce future wildfire severity, or prevent deforestation. Although fire severity and post-fire tree regeneration have been indicated as important influences on long-term carbon dynamics, it remains unclear how natural variability in these processes might affect the ability of fuel treatments to protect forest carbon resources. We surveyed a wildfire where fuel treatments were put in place before fire and estimated the short-term impact of treatment and wildfire on aboveground carbon stocks at our study site. We then used a common vegetation growth simulator in conjunction with sensitivity analysis techniques to assess how predicted timescales of carbon recovery after fire are sensitive to variation in rates of fire-related tree mortality, and post-fire tree regeneration. Results We found that fuel reduction treatments were successful at ameliorating fire severity at our study site by removing an estimated 36% of aboveground biomass. Treated and untreated stands stored similar amounts of carbon three years after wildfire, but differences in fire severity were such that untreated stands maintained only 7% of aboveground carbon as live trees, versus 51% in treated stands. Over the long-term, our simulations suggest that treated stands in our study area will recover baseline carbon storage 10–35 years more quickly than untreated stands. Our sensitivity analysis found that rates of fire-related tree mortality strongly influence estimates of post-fire carbon recovery. Rates of regeneration were less influential on recovery timing, except when fire severity was high. Conclusions Our ability to predict

  19. Variation in tree mortality and regeneration affect forest carbon recovery following fuel treatments and wildfire in the Lake Tahoe Basin, California, USA.

    Science.gov (United States)

    Carlson, Chris H; Dobrowski, Solomon Z; Safford, Hugh D

    2012-06-28

    Forest fuel treatments have been proposed as tools to stabilize carbon stocks in fire-prone forests in the Western U.S.A. Although fuel treatments such as thinning and burning are known to immediately reduce forest carbon stocks, there are suggestions that these losses may be paid back over the long-term if treatments sufficiently reduce future wildfire severity, or prevent deforestation. Although fire severity and post-fire tree regeneration have been indicated as important influences on long-term carbon dynamics, it remains unclear how natural variability in these processes might affect the ability of fuel treatments to protect forest carbon resources. We surveyed a wildfire where fuel treatments were put in place before fire and estimated the short-term impact of treatment and wildfire on aboveground carbon stocks at our study site. We then used a common vegetation growth simulator in conjunction with sensitivity analysis techniques to assess how predicted timescales of carbon recovery after fire are sensitive to variation in rates of fire-related tree mortality, and post-fire tree regeneration. We found that fuel reduction treatments were successful at ameliorating fire severity at our study site by removing an estimated 36% of aboveground biomass. Treated and untreated stands stored similar amounts of carbon three years after wildfire, but differences in fire severity were such that untreated stands maintained only 7% of aboveground carbon as live trees, versus 51% in treated stands. Over the long-term, our simulations suggest that treated stands in our study area will recover baseline carbon storage 10-35 years more quickly than untreated stands. Our sensitivity analysis found that rates of fire-related tree mortality strongly influence estimates of post-fire carbon recovery. Rates of regeneration were less influential on recovery timing, except when fire severity was high. Our ability to predict the response of forest carbon resources to anthropogenic and

  20. Chemical composition of the mineral waters of the Congo River

    International Nuclear Information System (INIS)

    Tshiashala, M.D.; Lumu, B.M.; Lobo, K.K.; Tshisumpa, M.; Wembo, L.S.

    2003-01-01

    Atomic absorption spectrophotometry has been applied to river Congo waters for a global monitoring of trace element contents. 15 elements Ag, Au, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb and Zn have been determined in samples collected at 2 sites along the river Congo. Results are compared with those observed in other river waters collected in Kinshasa and elsewhere and for compliance with the international quality standards elaborated by the Who, USA and SSRU. The waters of river Congo have been found less mineralized than those of river Niger. They are of the same order of magnitude than those observed in some local rivers such as Ndjili, Lubudi, Funa, Tshangu and Tshenke.

  1. 78 FR 69363 - Lake Tahoe Basin Management Unit, California, Heavenly Mountain Resort Epic Discovery Project

    Science.gov (United States)

    2013-11-19

    ... DEPARTMENT OF AGRICULTURE Forest Service Lake Tahoe Basin Management Unit, California, Heavenly Mountain Resort Epic Discovery Project AGENCY: Lake Tahoe Basin Management Unit, Forest Service, USDA...: The Epic Discovery Project is intended to enhance summer activities in response to the USDA Forest...

  2. The Amazon Basin in transition

    Science.gov (United States)

    Eric A. Davidson; Alessandro C. de Araujo; Paulo Artaxo; Jennifer K. Balch; I. Foster Brown; Mercedes M.C. Bustamente; Michael T. Coe; Ruth S. DeFriess; Michael Keller; Marcos Longo; J. William Munger; Wilfrid Schroeder; Britaldo Soares-Filho; Carlos M. Souza, Jr.; Steven C. Wofsy

    2012-01-01

    Agricultural expansion and climate variability have become important agents of disturbance in the Amazon basin. Recent studies have demonstrated considerable resilience of Amazonian forests to moderate annual drought, but they also show that interactions between deforestation, fire and drought potentially lead to losses of carbon storage and changes in regional...

  3. [Emerging diseases. Crimean-Congo hemorrhagic fever].

    Science.gov (United States)

    Kuljić-Kapulica, Nada

    2004-01-01

    Recognized for many years in central Asia and Eastern Europe, Crimean-Congo hemorrhagic fever (CCHF) is a severe zoonotic disease which affects people coming into contact with livestock or ticks. The range of the CCHF virus is now known to extend form central Asia to India, Pakistan, Afghanistan, Iran, Iraq, the Middle East, Eastern Europe, and to most of Saharan and sub-Saharan Africa. CCHF virus is a member of the Bunyavirus family, and is classified as a Nairovirus. After an incubation period of approximately 3 to 6 days the abrupt onset of acute febrile illness occurs. The first symptoms are similar to severe influenza and include fever, headache, severe back and abdominal pain. The hemorrhagic fever manifestations occur after several days of illnesses and include petechial rash, ecchymoses, hematemmesis, and melenna. Cases typically present with some form of hepatitis. The mortality rate is 10-50% in different outbreaks with deaths typically occurring during the second week of illness. The genus Hyalomma of ixodid ticks is the most important vector of the CCHF virus. Vertebrates including birds and small animals provide excellent amplifier hosts of both the virus and the tick. The virus can be transmitted to humans by direct contact with infected animals and from person to person. Early diagnosis is possible in special laboratories using antigen detection by imunofluorescence or ELISA tests or molecular methods as PCR and antibody detection. Tick control measures need to be emphasized and utilized to prevent CCHF. This includes spraying camp sites, clothing and danger areas with acaricides or repellent. Strict isolation of patients with CCHF and a focus on barrier nursing would help to prevent nosocomial spread. Presently the vaccine is a dangerous mouse brain-derived version. Future development of a vaccine would help to prevent human infection.

  4. Leap frog in slow motion: Divergent responses of tree species and life stages to climatic warming in Great Basin subalpine forests.

    Science.gov (United States)

    Smithers, Brian V; North, Malcolm P; Millar, Constance I; Latimer, Andrew M

    2018-02-01

    In response to climate warming, subalpine treelines are expected to move up in elevation since treelines are generally controlled by growing season temperature. Where treeline is advancing, dispersal differences and early life stage environmental tolerances are likely to affect how species expand their ranges. Species with an establishment advantage will colonize newly available habitat first, potentially excluding species that have slower establishment rates. Using a network of plots across five mountain ranges, we described patterns of upslope elevational range shift for the two dominant Great Basin subalpine species, limber pine and Great Basin bristlecone pine. We found that the Great Basin treeline for these species is expanding upslope with a mean vertical elevation shift of 19.1 m since 1950, which is lower than what we might expect based on temperature increases alone. The largest advances were on limber pine-dominated granitic soils, on west aspects, and at lower latitudes. Bristlecone pine juveniles establishing above treeline share some environmental associations with bristlecone adults. Limber pine above-treeline juveniles, in contrast, are prevalent across environmental conditions and share few environmental associations with limber pine adults. Strikingly, limber pine is establishing above treeline throughout the region without regard to site characteristic such as soil type, slope, aspect, or soil texture. Although limber pine is often rare at treeline where it coexists with bristlecone pine, limber pine juveniles dominate above treeline even on calcareous soils that are core bristlecone pine habitat. Limber pine is successfully "leap-frogging" over bristlecone pine, probably because of its strong dispersal advantage and broader tolerances for establishment. This early-stage dominance indicates the potential for the species composition of treeline to change in response to climate change. More broadly, it shows how species differences in dispersal

  5. Satellite altimetry over large hydrological basins

    Science.gov (United States)

    Calmant, Stephane

    2015-04-01

    The use of satellite altimetry for hydrological applications, either it is basin management or hydrological modeling really started with the 21st century. Before, during two decades, the efforts were concentrated on the data processing until a precision of a few decimeters could be achieved. Today, several web sites distribute hundreds of series spread over hundeds of rivers runing in the major basins of the world. Among these, the Amazon basin has been the most widely studied. Satellite altimetry is now routinely used in this transboundary basin to predict discharges ranging over 4 orders of magnitude. In a few years, satellite altimetry should evolve dramatically. This year, we should see the launchs of Jason-3 and that of Sentinel-3A operating in SAR mode. With SAR, the accuracy and resolution of a growing number of measurements should be improved. In 2020, SWOT will provide a full coverage that will join in a unique framework all the previous and forthcoming missions. These technical and thematical evolutions will be illustrated by examples taken in the Amazon and Congo basin.

  6. D3.2 The DR. Congo review

    DEFF Research Database (Denmark)

    Mandrup, Thomas

    2017-01-01

    , representatives of the Congolese authorities, NGOs and other IOs. EU involvement started with the deployment of Artemis in 2003, and the study ends with the closure of EUSEC in July 2016. All EU missions in the Democratic Republic of Congo (DRC) have been part of EU support for the transition and implementation...

  7. Crimean-Congo Hemorrhagic Fever Virus in Bulgaria and Turkey

    Czech Academy of Sciences Publication Activity Database

    Mertens, M.; Schuster, I.; Sas, M. A.; Vatansever, Z.; Hubálek, Zdeněk; Güven, E.; Deniz, A.; Georgiev, G.; Peshev, R.; Groschup, M. H.

    2016-01-01

    Roč. 16, č. 9 (2016), s. 619-623 ISSN 1530-3667 EU Projects: European Commission(XE) 261504 - EDENEXT Institutional support: RVO:68081766 Keywords : Crimean-Congo hemorrhagic fever virus: CCHFV * domestic animals * ELISA * epidemiology Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.045, year: 2016

  8. Physiological and biochemical responses of Chlorella vulgaris to Congo red.

    Science.gov (United States)

    Hernández-Zamora, Miriam; Perales-Vela, Hugo Virgilio; Flores-Ortíz, César Mateo; Cañizares-Villanueva, Rosa Olivia

    2014-10-01

    Extensive use of synthetic dyes in many industrial applications releases large volumes of wastewater. Wastewaters from dying industries are considered hazardous and require careful treatment prior to discharge into receiving water bodies. Dyes can affect photosynthetic activities of aquatic flora and decrease dissolved oxygen in water. The aim of this study was to evaluate the effect of Congo red on growth and metabolic activity of Chlorella vulgaris after 96h exposure. Exposure of the microalga to Congo red reduced growth rate, photosynthesis and respiration. Analysis of chlorophyll a fluorescence emission showed that the donor side of photosystem II was affected at high concentrations of Congo red. The quantum yield for electron transport (φEo), the electron transport rate (ETR) and the performance index (PI) also decreased. The reduction in the ability to absorb and use the quantum energy increased non-photochemical (NPQ) mechanisms for thermal dissipation. Overall, Congo red affects growth and metabolic activity in photosynthetic organisms in aquatic environments. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Evaluation of patients with Crimean-Congo hemorrhagic fever in ...

    African Journals Online (AJOL)

    Background: Crimean-Congo hemorrhagic fever (CCHF), which is associated with a high mortality rate in the Black Sea region of Turkey, has received increasing attention. Objective: In this study, the epidemiological features, clinical and laboratory findings, treatments, and outcomes of patients diagnosed with CCHF ...

  10. Crimean-Congo Hemorrhagic Fever, Kazakhstan, 2009–2010

    Science.gov (United States)

    Knust, Barbara; Medetov, Zhumagul B.; Kyraubayev, Kakimzhan B.; Bumburidi, Yekaterina; Erickson, Bobbie Rae; MacNeil, Adam; Bayserkin, Baurzhan S.; Ospanov, Kenes S.

    2012-01-01

    We evaluated Crimean-Congo hemorrhagic fever (CCHF) surveillance data from southern Kazakhstan during 2009–2010 and found both spatial and temporal association between reported tick bites and CCHF cases. Public health measures should center on preventing tick bites, increasing awareness of CCHF signs and symptoms, and adopting hospital infection control practices. PMID:22469505

  11. Risk Assessment: Democratic Republic of Congo Post-Laurent ...

    African Journals Online (AJOL)

    political system as opposed to the view that it was merely a power struggle between Kabila on the .... Local actors and international mining companies built alliances exploiting Congo's minerals to gain a ... They are preparing a contingency plan for their activities in the post-Laurent Kabila era, for ... small arms in the DRC.33.

  12. Phonology and Morphology of Mambay (Niger-Congo, Adamawa)

    NARCIS (Netherlands)

    Anonby, Erik John

    2008-01-01

    Mambay is an Adamawa (Niger-Congo) language spoken by 15,000 people in Chad and Cameroon. The study opens with historical and linguistic background. A phonological inventory of the language is then presented and distribution patterns are examined. Some striking phenomena include a profoundly

  13. Sorption behavior of congo red on different plant leaves (abstract)

    International Nuclear Information System (INIS)

    Khan, M.I.; Mirza, M.L.; Zafar, S.; Khalid, N.

    2011-01-01

    Batch adsorption studies were carried out to evaluate the potential of different plant leaves (Bougainvillaea Glabra and Citrus Sinensis) for the removal of Congo red dye from aqueous solution by optimizing different parameters such as effect of shaking time, adsorbent dose, initial adsorbate concentration, temperature etc. The experimental data was subjected to different types of isotherm models such as Freundlich, Langmuir and Dubinin-Radushkevich. The maximum adsorption capacity was calculated and was comparable for both the leaves through Freundlich isotherm by using the optimized parameters of weight and time at room temperature. The sorption mean free energy from Dubinin-Radushkevich isotherm was also determined and compared. Pseudo-first and Pseudo-second order kinetics models were tested for the adsorption of Congo red on plant leaves powder. The experimental data fitted well for Pseudo-second order model. The uptake of Congo red was also studied with the variation of temperature. Thermodynamic parameters have been calculated. The results indicate that the plant leaves of Bougainvilia Glabra and Citrus Sinensis are efficient adsorbents for Congo red dye from aqueous solutions and can be used for wastewater management. (author)

  14. Modelling basin-wide variations in Amazon forest productivity – Part 1: Model calibration, evaluation and upscaling functions for canopy photosynthesis

    Directory of Open Access Journals (Sweden)

    L. M. Mercado

    2009-07-01

    Full Text Available Given the importance of Amazon rainforest in the global carbon and hydrological cycles, there is a need to parameterize and validate ecosystem gas exchange and vegetation models for this region in order to adequately simulate present and future carbon and water balances. In this study, a sun and shade canopy gas exchange model is calibrated and evaluated at five rainforest sites using eddy correlation measurements of carbon and energy fluxes.

    Results from the model-data evaluation suggest that with adequate parameterisation, photosynthesis models taking into account the separation of diffuse and direct irradiance and the dynamics of sunlit and shaded leaves can accurately represent photosynthesis in these forests. Also, stomatal conductance formulations that only take into account atmospheric demand fail to correctly simulate moisture and CO2 fluxes in forests with a pronounced dry season, particularly during afternoon conditions. Nevertheless, it is also the case that large uncertainties are associated not only with the eddy correlation data, but also with the estimates of ecosystem respiration required for model validation. To accurately simulate Gross Primary Productivity (GPP and energy partitioning the most critical parameters and model processes are the quantum yield of photosynthetic uptake, the maximum carboxylation capacity of Rubisco, and simulation of stomatal conductance.

    Using this model-data synergy, we developed scaling functions to provide estimates of canopy photosynthetic parameters for a range of diverse forests across the Amazon region, utilising the best fitted parameter for maximum carboxylation capacity of Rubisco, and foliar nutrients (N and P for all sites.

  15. Changes in land cover and carbon emissions to 2050 from African tropical forests using policy scenarios

    Science.gov (United States)

    Laporte, N.; Galford, G. L.; Soares Filho, B. S.

    2011-12-01

    Africa has the second largest block of rainforest in the world, next to the Amazon basin, with the majority of the carbon being stored in the dense humid forests of the Democratic Republic of the Congo (DRC). Historically, political instability in the DRC kept development and deforestation low, with primary forest uses being extensive logging and small scale agriculture. In the last decade, political stability has opened the country to foreign investment in forested areas, largely for industrial-scale oil palm plantations and more recently to rice production. The DRC ranks worst on the IFPRI global hunger index, scoring "extremely serious" based on the proportion of undernourished population, prevalence of underweight in children under 5 and the mortality rates of children under 5. In fact, DRC saw its hunger score increase (worsen) from 1990 to 2010, with a 66% gain compared to the other 8 worsening countries increasing only 21% or less. This is a critical time for policy in the DRC, where business-as-usual (relatively low deforestation rates) is unlikely to continue given today's relative political stability and economic stabilization compared to the 1990s. The country must examine options for forest conservation in balance with foreign investment for use of forest resources, national development of rural livelihoods and domestic production of food. Here we present deforestation trajectories simulated through the year 2050 under a set of scenarios. The scenarios consider the relative carbon emissions from business-as-usual (no new policy), conservation (policy favoring protection and enforcement for forest areas), and a food security scenario (favoring clearing for industrial agriculture, extractive timber resources and development of new agricultural areas). Carbon emissions for each scenario are estimated with a coupled bookkeeping model. These scenarios are not predictive of the future, rather, they are meant to provide an understanding of the outcomes of

  16. Quantification of land cover and land use within the rural complex of the Democratic Republic of Congo

    Science.gov (United States)

    Molinario, G.; Hansen, M. C.; Potapov, P. V.; Tyukavina, A.; Stehman, S.; Barker, B.; Humber, M.

    2017-10-01

    The rural complex is the inhabited agricultural land cover mosaic found along the network of rivers and roads in the forest of the Democratic Republic of Congo. It is a product of traditional small-holder shifting cultivation. To date, thanks to its distinction from primary forest, this area has been mapped as relatively homogenous, leaving the proportions of land cover heterogeneity within it unknown. However, the success of strategies for sustainable development, including land use planning and payment for ecosystem services, such as Reduced Emissions from Deforestation and Degradation, depends on the accurate characterization of the impacts of land use on natural resources, including within the rural complex. We photo-interpreted a simple random sample of 1000 points in the established rural complex, using 3106 high resolution satellite images obtained from the National Geospatial-Intelligence Agency, together with 406 images from Google Earth, spanning the period 2008-2016. Results indicate that nationally the established rural complex includes 5% clearings, 10% active fields, 26% fallows, 34% secondary forest, 2% wetland forest, 11% primary forest, 6% grasslands, 3% roads and settlements and 2% commercial plantations. Only a small proportion of sample points were plantations, while other commercial dynamics, such as logging and mining, were not detected in the sample. The area of current shifting cultivation accounts for 76% of the established rural complex. Added to primary forest (11%), this means that 87% of the rural complex is available for shifting cultivation. At the current clearing rate, it would take ~18 years for a complete rotation of the rural complex to occur. Additional pressure on land results in either the cultivation of non-preferred land types within the rural complex (such as wetland forest), or expansion of agriculture into nearby primary forests, with attendant impacts on emissions, habitat loss and other ecosystems services.

  17. Plantes aromatiques du Plateau des Cataractes (Bassin du Congo. Caractérisation du chémotype de l'huile essentielle de Cymbopogon nardus (L. Rendle acclimaté au Congo-Brazzaville

    Directory of Open Access Journals (Sweden)

    Silou, T.

    2017-01-01

    Full Text Available Aromatic plants from the Plateau des Cataractes (Congo Basin. Chemotype characterization of essential oil of Cymbopogon nardus (L. Rendle acclimatized in Congo-Brazzaville. Description. The essential oils of Cymbopogon nardus (L. Rendle, Cymbopogon winterianus Jowitt, Cymbopogon flexuosus (Nees ex Steud. Wats and Cymbopogon citratus L. (DC. Stapf (lemongrass consist of more than 80% of the following constituents: citronellal, geraniol, citral, citronellol, geranyl acetate, and limonene. For the purposes of business transactions, it is therefore important to know the exact chemical composition of the essential oils produced. Objectives. Chemotype evaluation of C. nardus acclimatized on the Plateau des Cataractes. Method. The essential oils of C. nardus were extracted by hydrodistillation and analyzed by chromatography (GC and GC/MS over a period of more than ten years. Results. Cymbopogon nardus was found to produce a Java type citronella essential oil (C. winterianus with the following profile: citronellal (40-48%, geraniol (10-22%, citronellol (10-12%, limonene (2-3%, geranyl acetate (1-2%, linalool (1%. The difference between these two types of citronella, Java and Ceylon, was based on the relative proportions of their three main constituents: citronellal, geraniol and citronellol. Cymbopogon nardus is known for its high variability, with two varieties and sept subvarieties. Conclusions. The citronella established in West and Central Africa under the name of Cymbopogon nardus (Java type could be considered a Cymbopogon winterianus Jowitt, based on the chemical composition of its essential oil.

  18. Characterizing the phylogenetic tree community structure of a protected tropical rain forest area in Cameroon.

    Science.gov (United States)

    Manel, Stéphanie; Couvreur, Thomas L P; Munoz, François; Couteron, Pierre; Hardy, Olivier J; Sonké, Bonaventure

    2014-01-01

    Tropical rain forests, the richest terrestrial ecosystems in biodiversity on Earth are highly threatened by global changes. This paper aims to infer the mechanisms governing species tree assemblages by characterizing the phylogenetic structure of a tropical rain forest in a protected area of the Congo Basin, the Dja Faunal Reserve (Cameroon). We re-analyzed a dataset of 11538 individuals belonging to 372 taxa found along nine transects spanning five habitat types. We generated a dated phylogenetic tree including all sampled taxa to partition the phylogenetic diversity of the nine transects into alpha and beta components at the level of the transects and of the habitat types. The variation in phylogenetic composition among transects did not deviate from a random pattern at the scale of the Dja Faunal Reserve, probably due to a common history and weak environmental variation across the park. This lack of phylogenetic structure combined with an isolation-by-distance pattern of taxonomic diversity suggests that neutral dispersal limitation is a major driver of community assembly in the Dja. To assess any lack of sensitivity to the variation in habitat types, we restricted the analyses of transects to the terra firme primary forest and found results consistent with those of the whole dataset at the level of the transects. Additionally to previous analyses, we detected a weak but significant phylogenetic turnover among habitat types, suggesting that species sort in varying environments, even though it is not predominating on the overall phylogenetic structure. Finer analyses of clades indicated a signal of clustering for species from the Annonaceae family, while species from the Apocynaceae family indicated overdispersion. These results can contribute to the conservation of the park by improving our understanding of the processes dictating community assembly in these hyperdiverse but threatened regions of the world.

  19. Characterizing the Phylogenetic Tree Community Structure of a Protected Tropical Rain Forest Area in Cameroon

    Science.gov (United States)

    Munoz, François; Couteron, Pierre; Hardy, Olivier J.; Sonké, Bonaventure

    2014-01-01

    Tropical rain forests, the richest terrestrial ecosystems in biodiversity on Earth are highly threatened by global changes. This paper aims to infer the mechanisms governing species tree assemblages by characterizing the phylogenetic structure of a tropical rain forest in a protected area of the Congo Basin, the Dja Faunal Reserve (Cameroon). We re-analyzed a dataset of 11538 individuals belonging to 372 taxa found along nine transects spanning five habitat types. We generated a dated phylogenetic tree including all sampled taxa to partition the phylogenetic diversity of the nine transects into alpha and beta components at the level of the transects and of the habitat types. The variation in phylogenetic composition among transects did not deviate from a random pattern at the scale of the Dja Faunal Reserve, probably due to a common history and weak environmental variation across the park. This lack of phylogenetic structure combined with an isolation-by-distance pattern of taxonomic diversity suggests that neutral dispersal limitation is a major driver of community assembly in the Dja. To assess any lack of sensitivity to the variation in habitat types, we restricted the analyses of transects to the terra firme primary forest and found results consistent with those of the whole dataset at the level of the transects. Additionally to previous analyses, we detected a weak but significant phylogenetic turnover among habitat types, suggesting that species sort in varying environments, even though it is not predominating on the overall phylogenetic structure. Finer analyses of clades indicated a signal of clustering for species from the Annonaceae family, while species from the Apocynaceae family indicated overdispersion. These results can contribute to the conservation of the park by improving our understanding of the processes dictating community assembly in these hyperdiverse but threatened regions of the world. PMID:24936786

  20. Intensive measurements of gas, water, and energy exchange between vegetation and troposphere during the MONTES campaign in a vegetation gradient from short semi-desertic shrublands to tall wet temperate forests in the NW Mediterranean Basin

    Science.gov (United States)

    Peñuelas, J.; Guenther, A.; Rapparini, F.; Llusia, J.; Filella, I.; Seco, R.; Estiarte, M.; Mejia-Chang, M.; Ogaya, R.; Ibañez, J.; Sardans, J.; Castaño, L. M.; Turnipseed, A.; Duhl, T.; Harley, P.; Vila, J.; Estavillo, J. M.; Menéndez, S.; Facini, O.; Baraldi, R.; Geron, C.; Mak, J.; Patton, E. G.; Jiang, X.; Greenberg, J.

    2013-08-01

    MONTES (“Woodlands”) was a multidisciplinary international field campaign aimed at measuring energy, water and especially gas exchange between vegetation and atmosphere in a gradient from short semi-desertic shrublands to tall wet temperate forests in NE Spain in the North Western Mediterranean Basin (WMB). The measurements were performed at a semidesertic area (Monegros), at a coastal Mediterranean shrubland area (Garraf), at a typical Mediterranean holm oak forest area (Prades) and at a wet temperate beech forest (Montseny) during spring (April 2010) under optimal plant physiological conditions in driest-warmest sites and during summer (July 2010) with drought and heat stresses in the driest-warmest sites and optimal conditions in the wettest-coolest site. The objective of this campaign was to study the differences in gas, water and energy exchange occurring at different vegetation coverages and biomasses. Particular attention was devoted to quantitatively understand the exchange of biogenic volatile organic compounds (BVOCs) because of their biological and environmental effects in the WMB. A wide range of instruments (GC-MS, PTR-MS, meteorological sensors, O3 monitors,…) and vertical platforms such as masts, tethered balloons and aircraft were used to characterize the gas, water and energy exchange at increasing footprint areas by measuring vertical profiles. In this paper we provide an overview of the MONTES campaign: the objectives, the characterization of the biomass and gas, water and energy exchange in the 4 sites-areas using satellite data, the estimation of isoprene and monoterpene emissions using MEGAN model, the measurements performed and the first results. The isoprene and monoterpene emission rates estimated with MEGAN and emission factors measured at the foliar level for the dominant species ranged from about 0 to 0.2 mg m-2 h-1 in April. The warmer temperature in July resulted in higher model estimates from about 0 to ca. 1.6 mg m-2 h-1 for

  1. Contrasting winter and summer VOC mixing ratios at a forest site in the Western Mediterranean Basin: the effect of local biogenic emissions

    Directory of Open Access Journals (Sweden)

    R. Seco

    2011-12-01

    Full Text Available Atmospheric volatile organic compounds (VOCs are involved in ozone and aerosol generation, thus having implications for air quality and climate. VOCs and their emissions by vegetation also have important ecological roles as they can protect plants from stresses and act as communication cues between plants and between plants and animals. In spite of these key environmental and biological roles, the reports on seasonal and daily VOC mixing ratios in the literature for Mediterranean natural environments are scarce.

    We conducted seasonal (winter and summer measurements of VOC mixing ratios in an elevated (720 m a.s.l. holm oak Mediterranean forest site near the metropolitan area of Barcelona (NE Iberian Peninsula. Methanol was the most abundant compound among all the VOCs measured in both seasons. While aromatic VOCs showed almost no seasonal variability, short-chain oxygenated VOCs presented higher mixing ratios in summer, presumably due to greater emission by vegetation and increased photochemistry, both enhanced by the high temperatures and solar radiation in summer. Isoprenoid VOCs showed the biggest seasonal change in mixing ratios: they increased by one order of magnitude in summer, as a result of the vegetation's greater physiological activity and emission rates. The maximum diurnal concentrations of ozone increased in summer too, most likely due to more intense photochemical activity and the higher levels of VOCs in the air.

    The daily variation of VOC mixing ratios was mainly governed by the wind regime of the mountain, as the majority of the VOC species analyzed followed a very similar diel cycle. Mountain and sea breezes that develop after sunrise advect polluted air masses to the mountain. These polluted air masses had previously passed over the urban and industrial areas surrounding the Barcelona metropolitan area, where they were enriched in NOx and in VOCs of biotic and abiotic origin. Moreover, these

  2. Contrasting winter and summer VOC mixing ratios at a forest site in the Western Mediterranean Basin: the effect of local biogenic emissions

    Science.gov (United States)

    Seco, R.; Peñuelas, J.; Filella, I.; Llusià, J.; Molowny-Horas, R.; Schallhart, S.; Metzger, A.; Müller, M.; Hansel, A.

    2011-12-01

    Atmospheric volatile organic compounds (VOCs) are involved in ozone and aerosol generation, thus having implications for air quality and climate. VOCs and their emissions by vegetation also have important ecological roles as they can protect plants from stresses and act as communication cues between plants and between plants and animals. In spite of these key environmental and biological roles, the reports on seasonal and daily VOC mixing ratios in the literature for Mediterranean natural environments are scarce. We conducted seasonal (winter and summer) measurements of VOC mixing ratios in an elevated (720 m a.s.l.) holm oak Mediterranean forest site near the metropolitan area of Barcelona (NE Iberian Peninsula). Methanol was the most abundant compound among all the VOCs measured in both seasons. While aromatic VOCs showed almost no seasonal variability, short-chain oxygenated VOCs presented higher mixing ratios in summer, presumably due to greater emission by vegetation and increased photochemistry, both enhanced by the high temperatures and solar radiation in summer. Isoprenoid VOCs showed the biggest seasonal change in mixing ratios: they increased by one order of magnitude in summer, as a result of the vegetation's greater physiological activity and emission rates. The maximum diurnal concentrations of ozone increased in summer too, most likely due to more intense photochemical activity and the higher levels of VOCs in the air. The daily variation of VOC mixing ratios was mainly governed by the wind regime of the mountain, as the majority of the VOC species analyzed followed a very similar diel cycle. Mountain and sea breezes that develop after sunrise advect polluted air masses to the mountain. These polluted air masses had previously passed over the urban and industrial areas surrounding the Barcelona metropolitan area, where they were enriched in NOx and in VOCs of biotic and abiotic origin. Moreover, these polluted air masses receive additional biogenic

  3. Search Results | Page 5 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-07-30

    Jul 30, 2016 ... Altering the Climate of Poverty under Climate Change : the Forests of Congo Basin (sub-Saharan Africa). The forests of the Congo basin provide ecosystem services to over 80% of the population living in or near them. Project.

  4. Animal breeding of the Saltov Culture bearers from the forest-steppe part of the Seversky Donets Basin (Ukraine. Part 3

    Directory of Open Access Journals (Sweden)

    Vladimir Koloda

    2017-09-01

    Full Text Available The paper presents a description and analysis of the archaeozoological material from medieval monuments of Saltov Culture (Kharkiv region, Ukraine in a wide geographical, climatic, cultural, historical, and archaeological context. The proposed statistical, biometric, and demographic analysis of the archaeozoological material reveals a settled character of Saltovian economy and animal husbandry from the forest-steppe zone. The settled character of animal breeding is suggested by the dominance of cattle and the significant presence of the domestic pig in the domestic herd, while the small cattle had a subordinate role in economy. The important role of the domestic horse (after cattle represents a specific feature of the Saltovian domestic herd that distinguishes the Saltovian archaeozoological complexes from other agriculture based cultures from Eastern Europe. The third part of the work proposes a comparative analysis of the archaeozoological complexes from Middle Age of Kharkov Region.

  5. Combining multiple approaches and optimized data resolution for an improved understanding of stream temperature dynamics of a forested headwater basin in the Southern Appalachians

    Science.gov (United States)

    Belica, L.; Mitasova, H.; Caldwell, P.; McCarter, J. B.; Nelson, S. A. C.

    2017-12-01

    Thermal regimes of forested headwater streams continue to be an area of active research as climatic, hydrologic, and land cover changes can influence water temperature, a key aspect of aquatic ecosystems. Widespread monitoring of stream temperatures have provided an important data source, yielding insights on the temporal and spatial patterns and the underlying processes that influence stream temperature. However, small forested streams remain challenging to model due to the high spatial and temporal variability of stream temperatures and the climatic and hydrologic conditions that drive them. Technological advances and increased computational power continue to provide new tools and measurement methods and have allowed spatially explicit analyses of dynamic natural systems at greater temporal resolutions than previously possible. With the goal of understanding how current stream temperature patterns and processes may respond to changing landcover and hydroclimatoligical conditions, we combined high-resolution, spatially explicit geospatial modeling with deterministic heat flux modeling approaches using data sources that ranged from traditional hydrological and climatological measurements to emerging remote sensing techniques. Initial analyses of stream temperature monitoring data revealed that high temporal resolution (5 minutes) and measurement resolutions (guide field data collection for further heat flux modeling. By integrating multiple approaches and optimizing data resolution for the processes being investigated, small, but ecologically significant differences in stream thermal regimes were revealed. In this case, multi-approach research contributed to the identification of the dominant mechanisms driving stream temperature in the study area and advanced our understanding of the current thermal fluxes and how they may change as environmental conditions change in the future.

  6. CZO perspective in Central Africa : The Lopé watershed, Lopé National Park, Ogooué River basin, Gabon.

    Science.gov (United States)

    Braun, J. J.; Jeffery, K.; Koumba Pambo, A. F.; Paiz, M. C.; Richter, D., Jr.; John, P.; Jerome, G.

    2015-12-01

    Critical Zone Observatories (CZO) in equatorial regions are seldom (see e. g. http://www.czen.org/, USA and http://rnbv.ipgp.fr/, France). The equatorial zone of Central Africa is almost free of them with the exception of the CZO of the Upper Nyong river basin (organic-rich river on the lateritic plateau of South Cameroon; SO BVET, http://bvet.omp.obs-mip.fr/). On both sides of the Equator line, the Ogooué River Basin (215,000 km2) stretches on about 80% of the total area of Gabon and drains various geological and morpho-pedological contexts and feeds the sedimentation areas of the Central African passive margin (Guillochaux et al., 2014). The Upper Ogooué (up to Lambaréné) drains the stepped planation surface of the Congo craton while the Lower Ogooué drains Mesozoic and Cenozoic sedimentary terrains. The climate is equatorial (Pmean = 2500 mm/yr; Tmean = 26 °; %humidity > 80%). Continuous hydro-climatic chronicles exist for the period 1953-1974 (managed by ORSTOM, now IRD). The runoff at Lambaréné (92% of the basin area) is very high (714 mm/yr). With a rural density of 1 inhabitant/km2, it is one of the last largely pristine tropical forested ecosystems on the Planet. In addition, the basin will be, in the coming decades, the theatre of important anthropogenic changes (dams, agriculture, mining, urbanisation, …). However, a conservation plan with an ambitious sustainable development policy is set up. This plan articulates the environmental issues related to the emergence of the country. Because of these characteristics, the basin offers ideal conditions for studying the changes in equatorial region of hydro-climate, weathering/erosion regimes and regolith production based on morpho-pedological contexts and associated physical, chemical and biological processes. It is thus germane to launch an integrated CZO initiative at both regional scale and local scale. At the regional scale, we plan to reactivate some of the hydro-climatic stations located on the

  7. Uncertainty in the spatial distribution of tropical forest biomass: a comparison of pan-tropical maps.

    Science.gov (United States)

    Mitchard, Edward Ta; Saatchi, Sassan S; Baccini, Alessandro; Asner, Gregory P; Goetz, Scott J; Harris, Nancy L; Brown, Sandra

    2013-10-26

    Mapping the aboveground biomass of tropical forests is essential both for implementing conservation policy and reducing uncertainties in the global carbon cycle. Two medium resolution (500 m - 1000 m) pantropical maps of vegetation biomass have been recently published, and have been widely used by sub-national and national-level activities in relation to Reducing Emissions from Deforestation and forest Degradation (REDD+). Both maps use similar input data layers, and are driven by the same spaceborne LiDAR dataset providing systematic forest height and canopy structure estimates, but use different ground datasets for calibration and different spatial modelling methodologies. Here, we compare these two maps to each other, to the FAO's Forest Resource Assessment (FRA) 2010 country-level data, and to a high resolution (100 m) biomass map generated for a portion of the Colombian Amazon. We find substantial differences between the two maps, in particular in central Amazonia, the Congo basin, the south of Papua New Guinea, the Miombo woodlands of Africa, and the dry forests and savannas of South America. There is little consistency in the direction of the difference. However, when the maps are aggregated to the country or biome scale there is greater agreement, with differences cancelling out to a certain extent. When comparing country level biomass stocks, the two maps agree with each other to a much greater extent than to the FRA 2010 estimates. In the Colombian Amazon, both pantropical maps estimate higher biomass than the independent high resolution map, but show a similar spatial distribution of this biomass. Biomass mapping has progressed enormously over the past decade, to the stage where we can produce globally consistent maps of aboveground biomass. We show that there are still large uncertainties in these maps, in particular in areas with little field data. However, when used at a regional scale, different maps appear to converge, suggesting we can provide

  8. Runoff Responses to Forest Thinning at Plot and Catchment Scales in a Headwater Catchment Draining Japanese Cypress Forest

    Science.gov (United States)

    We examined the effect of forest thinning on runoff generation at plot and catchment scales in headwater basins draining a Japanese cypress (Chamaecyparis obtusa) forest. We removed 58.3% of the stems (corresponding to 43.2% of the basal area) in the treated headwater basin (catc...

  9. Therapeutic management of Crimean-Congo haemorrhagic fever.

    Science.gov (United States)

    de la Calle-Prieto, Fernando; Martín-Quirós, Alejandro; Trigo, Elena; Mora-Rillo, Marta; Arsuaga, Marta; Díaz-Menéndez, Marta; Arribas, José Ramón

    2017-06-29

    Crimean-Congo haemorrhagic fever has been reported in more than 30 countries in Africa, Asia, the Middle East and Eastern Europe, with an increasing incidence in recent years, especially in Europe. Because no specific treatments have demonstrated efficacy, supportive treatment is essential, as well as the provision of a centre with the appropriate means to guarantee the safety of its healthcare professionals. Laboratory monitoring of thrombocytopenia, severe coagulopathy or liver failure is of critical importance. Patients with Crimean-Congo haemorrhagic fever should be admitted to High Level Isolation Units where appropriate biocontainment procedures can prevent nosocomial transmission through infected fluids or accidents with contaminated material. In case of high-risk exposures, early administration of ribavirin should be considered. Copyright © 2017. Publicado por Elsevier España, S.L.U.

  10. Photoluminescence study of Congo red molecules under high pressure

    International Nuclear Information System (INIS)

    Wang, Z.P.; Zhang, Z.M.; Ding, Z.J.

    2007-01-01

    Pressure-induced changes on fluorescence spectra of Congo red molecules were examined up to 8.7 GPa using a diamond anvil cell at room temperature. The spectra changes are demonstrated to be sensitive to the pressure and solvent conditions. At hydrostatic pressure and with a solvent used as a pressure transmitting medium the fluorescence spectra show increase of intensity with elevated pressure up to about 2.3 GPa and then drop at higher pressures. For Congo red crystal under quasi-hydrostatic condition without solvent the fluorescence intensity decreases monotonically and the lower energy band becomes dominant with the pressure increasing. The three vibronic bands show red shifts with increase of pressure

  11. A Q fever case mimicking crimean-congo haemorrhagic fever

    Directory of Open Access Journals (Sweden)

    O Karabay

    2011-01-01

    Full Text Available Coxiella burnetii is the bacterium that causes Q fever. Human infection is mainly transmitted from cattle, goats and sheep. The disease is usually self-limited. Pneumonia and hepatitis are the most common clinical manifestations. In this study, we present a case of Q fever from the western part of Turkey mimicking Crimean-Congo haemorrhagic fever (CCHF in terms of clinical and laboratory findings.

  12. Democratic Republic of Congo: Background and U.S. Policy

    Science.gov (United States)

    2013-06-29

    ethnic Hutu extremists who fled to Congo from Rwanda after helping to carry out the 1994 genocide there; “Mai Mai,” a term that broadly refers to a... Rwanda , Uganda, Angola, and South Africa. U.S. policymakers, including in Congress, continue to debate the relative effectiveness of various policy tools...institutions and the military progressively deteriorated, while regional civil conflicts and the genocide in neighboring Rwanda spilled over the border

  13. Crimean-Congo hemorrhagic fever in Iran and neighboring countries

    DEFF Research Database (Denmark)

    Chinikar, S; Ghiasi, Seyed Mojtaba; Hewson, R

    2010-01-01

    Crimean-Congo hemorrhagic fever (CCHF) is a zoonotic viral disease that is asymptomatic in infected livestock, but a serious threat to humans. Human infections begin with nonspecific febrile symptoms, but progress to a serious hemorrhagic syndrome with a case fatality rate of 2-50%. Although the ...... in Iran and neighboring countries and provide evidence of over 5000 confirmed cases of CCHF in a single period/season....

  14. Mycoremediation of congo red dye by filamentous fungi

    OpenAIRE

    Bhattacharya, Sourav; Das, Arijit; G, Mangai.; K, Vignesh.; J, Sangeetha.

    2011-01-01

    Azo, anthroquinone and triphenylmethane dyes are the major classes of synthetic colourants, which are difficult to degrade and have received considerable attention. Congo red, a diazo dye, is considered as a xenobiotic compound, and is recalcitrant to biodegradative processes. Nevertheless, during the last few years it has been demonstrated that several fungi, under certain environmental conditions, are able to transfer azo dyes to non toxic products using laccases. The aim of this work was t...

  15. Possible sexual transmission of Crimean-Congo hemorrhagic fever

    Directory of Open Access Journals (Sweden)

    Natalia Yurievna Pshenichnaya

    2016-04-01

    Full Text Available Three cases of family transmission of laboratory-confirmed Crimean-Congo hemorrhagic fever (CCHF among spouses are reported. These spouses had sexual contact at the end of the incubation period or during the early stage of the mild form of CCHF, without any hemorrhagic symptoms in the first infected spouse. This report demonstrates that sexual contact may represent a real risk of CCHF transmission, even if the patient only experiences mild symptoms.

  16. Going for the play: Structural interpretation in offshore Congo

    Energy Technology Data Exchange (ETDEWEB)

    Platt, N.; Philip, P. (GECO-PRAKLA Exploration Services, Woking (United Kingdom)); Walter, S. (ARK Geophysics Ltd., Milton Keynes, (United Kingdom))

    1993-01-01

    Looking for new hydrocarbons in frontier areas, geologists and geophysicists use very trick in the book: plate tectonics, magnetic and gravity data, plain old geological horse sense and lots of seismic data. An interpretation team is followed, as they pick their way through a seismic survey shot in offshore Congo, Africa, searching for those areas (the plays) that show the greatest promise. 17 figs., 9 refs.

  17. Trace metals and persistent organic pollutants in sediments from river-reservoir systems in Democratic Republic of Congo (DRC): Spatial distribution and potential ecotoxicological effects.

    Science.gov (United States)

    Mwanamoki, Paola M; Devarajan, Naresh; Thevenon, Florian; Birane, Niane; de Alencastro, Luiz Felippe; Grandjean, Dominique; Mpiana, Pius T; Prabakar, Kandasamy; Mubedi, Josué I; Kabele, Christophe G; Wildi, Walter; Poté, John

    2014-09-01

    This paper discusses the occurrence and spatial distribution of metals and persistent organic pollutants (POPs: including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), Polybrominated diphenyl ethers (PBDEs), and polycyclic aromatic hydrocarbons (PAHs) in sediments from a river-reservoir system. Surface sediments were sampled from thirteen sites of the Congo River Basin and Lake Ma Vallée, both situated in the vicinity of the capital city Kinshasa (Congo Democratic Republic). Sediment qualities were evaluated using toxicity test based on exposing Ostracods to the sediment samples. The highest metal concentrations were observed in sediments subjected to anthropogenic influences, urban runoff and domestic and industrial wastewaters, discharge into the Congo River basin. Ostracods exposed to the sediments resulted in 100% mortality rates after 6d of incubation, indicating the ultimate toxicity of these sediments as well as potential environmental risks. The POPs and PAHs levels in all sediment samples were low, with maximum concentration found in the sediments (area of pool Malebo): OCP value ranged from 0.02 to 2.50 with ∑OCPs: 3.3μgkg(-1); PCB ranged from 0.07 to 0.99 with Total PCBs (∑7×4.3): 15.31μgkg(-1); PAH value ranged from 0.12 to 9.39 with ∑PAHs: 63.89μgkg(-1). Our results indicate that the deterioration of urban river-reservoir water quality result mainly from urban stormwater runoff, untreated industrial effluents which discharge into the river-reservoirs, human activities and uncontrolled urbanization. This study represents useful tools incorporated to evaluate sediment quality in river-reservoir systems which can be applied to similar aquatic environments. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Eddy covariance fluxes of the NO-O3-NO2 triad above the forest canopy at the ATTO Site in the Amazon Basin

    Science.gov (United States)

    Tsokankunku, Anywhere; Wolff, Stefan; Sörgel, Matthias; Berger, Martina; Zelger, Michael; Dlugi, Ralf

    2017-04-01

    Nitrogen monoxide (NO) and nitrogen dioxide (NO2) (denoted together as NOx) determine the abundance of the tropospheric oxidants OH, O3 and NO3 that regulate atmospheric self-cleaning. The three reactive trace gases NO, NO2 and O3 undergo a series of interconnected photochemical reactions and are often referred to as the NO-O3-NO2 triad. Ozone deposition is mainly controlled by stomatal uptake, thus contributes to oxidative stress for the plants. Similarly, nitrogen dioxide from above or below the canopy is deposited to leaves through stomatal uptake. NO emissions from soils contribute to above canopy O3 formation and accelerate OH recycling. Therefore, quantification of the exchange fluxes of these species between the atmosphere and the biosphere are important for atmospheric chemistry and ecosystem research as well. The eddy covariance method is state of the art for direct measurements of ecosystem fluxes of trace gases. Eddy covariance measurements of NOx in pristine environments are rare because of lack of availability of instruments with the required precision to resolve concentrations characteristic of these environments. The Amazon Tall Tower Observatory (ATTO) is located in a pristine rainforest environment in the Amazon basin about 150 km northeast of the city of Manaus. It is the ideal site for studying the biosphere-atmosphere exchange of the NO-O3-NO2 triad, being largely undisturbed by anthropogenic sources. During an intensive measurement campaign in November 2015 at the ATTO site, measurements of NO, NO2 and O3 were carried out at 42 m above ground level on the 80 m walk-up tower with a fast (5 Hz) and sensitive (radiation. Vertical concentration profile measurements of NO, NO2 and O3 were available at 8 levels on the INSTANT tower from a reactive trace gas profile system which has been operational at the site since 2012. From these measurements, we present eddy covariance fluxes of the NO-O3-NO2 triad. We relate the fluxes to the canopy

  19. Eddy Covariance Fluxes of the NO-O3-NO2 Triad above the Forest Canopy at the ATTO Site in the Amazon Basin

    Science.gov (United States)

    Tsokankunku, A.; Wolff, S.; Berger, M.; Zelger, M.; Dlugi, R. J. W.; Andreae, M. O.; Sörgel, M.

    2017-12-01

    Nitrogen monoxide (NO) and nitrogen dioxide (NO2) (denoted together as NOx) determine the abundance of the tropospheric oxidants OH, O3 and NO3 that regulate atmospheric self-cleaning. The three reactive trace gases NO, NO2 and O3 undergo a series of interconnected photochemical reactions and are therefore often referred to as the NO-O3-NO2 triad. Ozone deposition is mainly controlled by stomatal uptake, therefore resulting in oxidative stress for the plants. Similarly, nitrogen dioxide from above or below the canopy is deposited to leaves through stomatal uptake. NO emissions from soils contribute to above canopy O3 formation and accelerate OH recycling. Therefore, quantification of the biosphere-atmosphere exchange fluxes of these species is important for atmospheric chemistry and ecosystem research. The eddy covariance method is state of the art for direct measurements of ecosystem fluxes of trace gases. Eddy covariance measurements of NOx in pristine environments are rare because of lack of availability of instruments with the required precision to resolve concentrations characteristic of these environments with the required high time resolution. The Amazon Tall Tower Observatory (ATTO) is located in a pristine rainforest environment in the Amazon basin about 150 km northeast of the city of Manaus. It is the ideal site for studying the biosphere-atmosphere exchange of the NO-O3-NO2 triad, because of the absence of nearby anthropogenic sources. During an intensive measurement campaign in November 2015 at the ATTO site, measurements of NO, NO2 and O3 were carried out at 42 m above ground level on the 80 m walk-up tower with a fast (5 Hz) and sensitive (< 30 ppt) instrument (CLD790SR2, Eco Physics) for NO and NO2 and with 10 Hz for O3 (Enviscope GmbH). Additionally, a suite of micrometeorological instruments was installed, including a profile of 3-dimensional sonic anemometers and meteorological sensors. Vertical concentration profile measurements of NO, NO2 and O

  20. Contribution to the geology of the Niari basin: sedimentology and metallogeny of the mining region

    International Nuclear Information System (INIS)

    Bigotte, G.

    1956-01-01

    This thesis is divided in two parts: a detailed petrographical and stratigraphical study of the upper layers of calcareous schist in Congo which lead to some sedimentological considerations, and a metallogenic study of the ores of Niari basin which lead to a theoretical description of the metallogeny in Congo. In the first part, after a brief description of the methods used, a petrographical survey of the rocks of the upper layers of calcareous schist of the Boko-Congo area is given as well as sedimentological conclusions and stratigraphical data. The studies and conclusions related to this limited area are extended to a region scale. A structural study and precised descriptions of this region lead to an attempt of tectonic explanation. In the second part, an inventory and description of known mineralisation points in the Niari basin are given and in particular the detailed descriptions of four deposits: La Grande-Mine, M'Passa, Diangala and Djenguile. The interpretations and conclusions are based on the study of the general characters of the mineralisation in Niari basin and its comparison with the mineralisation in Katanga (now Shaba region) and North Rhodesia (now Zambia). (M.P.)

  1. Presumptive risk factors for monkeypox in rural communities in the Democratic Republic of the Congo.

    Directory of Open Access Journals (Sweden)

    Claire A Quiner

    Full Text Available Monkeypox virus (MPXV, a close relative of Variola virus, is a zoonotic virus with an unknown reservoir. Interaction with infected wildlife, bites from peri-domestic animals, and bushmeat hunting are hypothesized routes of infection from wildlife to humans. Using a Risk Questionnaire, performed in monkeypox-affected areas of rural Democratic Republic of the Congo, we describe the lifestyles and demographics associated with presumptive risk factors for MPXV infection. We generated two indices to assess risk: Household Materials Index (HMI, a proxy for socioeconomic status of households and Risk Activity Index (RAI, which describes presumptive risk for animal-to-human transmission of MPXV. Based on participant self-reported activity patterns, we found that people in this population are more likely to visit the forest than a market to fulfill material needs, and that the reported occupation is limited in describing behavior of individuals may participate. Being bitten by rodents in the home was commonly reported, and this was significantly associated with a low HMI. The highest scoring RAI sub-groups were 'hunters' and males aged ≥ 18 years; however, several activities involving MPXV-implicated animals were distributed across all sub-groups. The current analysis may be useful in identifying at-risk groups and help to direct education, outreach and prevention efforts more efficiently.

  2. Population structure and group composition of western lowland gorillas in north-western Republic of Congo.

    Science.gov (United States)

    Magliocca, F; Querouil, S; Gautier-Hion, A

    1999-01-01

    Population studies are an essential part of conservation actions. Under exceptional observation conditions we studied a western lowland gorilla population visiting the Maya salt-clearing (north of the Parc national d'Odzala, P.N.O., Congo) over an 8 month period; 36 groups and 18 solitary individuals (a total of 420 individuals) have been identified visiting the clearing, which suggests a high gorilla density in the region. Ninety-six percent of the gorillas entered the clearing in groups. One-male groups had a mean size of 11.2. Ninety percent of solitary individuals were silver-back males. Compared with other populations of both lowland gorillas and mountain gorillas, the Maya population had the highest immature rate and the highest number of infants per female. Ecological correlates that could explain the attractiveness of the Maya clearing are discussed. The present status and the renewal rate of the Maya population indicate the need for further studies and confirm the importance of developing eco-tourism in this region as part of the sustainable park management activities developed by the ECOFAC programme (European Union). The results also provide arguments to support the proposal for extending the P.N.O. to include this region, which is rich in salt-clearings and attracts many other key-species of mammal such as forest elephants.

  3. opulation growth and deforestation in the Volta River basin of Ghana ...

    African Journals Online (AJOL)

    The Volta River basin in Ghana, about 160,000 km2, is experiencing rapid deforestation. Paper uses satellite, household survey and population census data to relate trends and patterns of population in the Volta River sub-basins to forest cover. It assesses amount of forest available in 1990 and 2000, and the relationship ...

  4. Erosion by rain in the western Congo

    International Nuclear Information System (INIS)

    Ploey, J. de

    1967-01-01

    Vast expanses of the western part of central and southern Africa are covered with uniform, sandy formations of the Kalahari type. The topography of these areas and their present morphological characteristics are mainly the result of erosion by rain. Information on the hydrology of the surface waters in these areas is fairly limited and is insufficient to permit any conclusions regarding the way in which erosion by rain takes place. To obtain a better understanding of these phenomena, the author devised a series of experiments based on the use of 46 Sc-labelled radioactive sand. These experiments began at the beginning of the 1964/65 rainy season and are continuing. The experimental plot corresponds to convex and rectilinear portions of a hillside with a slope varying between 0 and 12 degrees. The vegetation consists of grassy savannah of substeppe appearance and secondary forests. Series of labelled samples were placed successively on the surface of the experimental plot and the erosive effect of rain was determined by measuring the residual concentrations after rainfall. Some samples were placed below a shield so as to eliminate the effects of splash and reveal the part played by runoff. Radiographic films were used to study the dispersion of labelled particles in the surrounding area. This radiographic method made it possible to determine the scale of erosion by splash for different rainfall conditions. The erosion diagrams obtained from these experiments show the correlations that exist between the intensity and duration of the rainfall and the erosion of the soil. Examination of the erosion diagrams and the shielded samples and analysis of the radiographs showed that erosion by rain on Kalahari ground covered with substeppe savannah is caused mainly by splash erosion and by dispersed, intermittent runoff. Sheet wash plays no part if the slope is less than 12 degrees. (author) [fr

  5. 13 Morphometric Analysis of Ogunpa and Ogbere Drainage Basins ...

    African Journals Online (AJOL)

    `123456789jkl''''#

    significance of these landscape parameters was ... reported that the geomorphic characteristics of a drainage basins play ... form and process of drainage basins that may ... tropical rain forest of Nigeria occupying an area of .... morphometric parameters such as relief, shape ... on floodplains can be pulled down while areas.

  6. Livelihood trends in Response to Climate Change in Forest Fringe ...

    African Journals Online (AJOL)

    One of the forest fringe communities in Ghana where the rural livelihoods of the people have been compromised due to deforestation and climate change is the Offin basin. The removal of forests impacts on local climate, water availability, and livelihoods due to influence of forests on precipitation and water balance. Fluxes ...

  7. Impacts of forest management on runoff and erosion

    Science.gov (United States)

    William J. Elliot; Brandon D. Glaza

    2009-01-01

    In a parallel study, ten small watersheds (about 5 ha) were installed in the Priest River Experimental Forest (PREF) in northern Idaho, and another ten were installed in the Boise Basin Experimental Forest (BBEF) in central Idaho. The long-term objective of the study is to compare the effects of different forest management activities on runoff and...

  8. Consommation de produits d'origine animale dans la concession forestière 039/11 de la SODEFOR à Oshwe (R.D. Congo

    Directory of Open Access Journals (Sweden)

    Semeki Ngabinzeke, J.

    2014-01-01

    Full Text Available Consumption of Products of Animal Origin in the Forest Concession 039/11 of the SODEFOR to Oshwe (D.R. Congo. To identify the main foods of animal origin consumed by people living in the concession 039/11 of the forest Development Company (SODEFOR in the Democratic Republic of the Congo, and to specify the determinants of consumption, 120 households in 3 villages (Taketa, Ikala 1 and Mombele and in the base of Nteno were surveyed for 30 days. The results show that bush meat represents 72.00% of the number of meals followed by fish (24.00%, and livestock products finally (3.10%. In total, 30 species of animals including 4 which are legally banned from hunting have been identified, for a total biomass of 1235 kg. Mammals represent 97.00% of animals consumed with a predominance of artiodactyls (71.60%, primates (15.40%, and rodents (9.10%. The duikers, the bushes and the atherure are the most represented. The choice of consumption is guided by the availability of the product, taste, and eating habits. The majority of households are supplied by intermediaries to whom they primarily buy animal parts. This study suggests a long term follow-up of hunting with an assessment of the abundance of animal species to guide the SODEFOR in the decision-making.

  9. Urban Forests

    Science.gov (United States)

    David Nowak

    2016-01-01

    Urban forests (and trees) constitute the second forest resource considered in this report. We specifically emphasize the fact that agricultural and urban forests exist on a continuum defined by their relationship (and interrelationship) with a given landscape. These two forest types generally serve different purposes, however. Whereas agricultural forests are...

  10. Background Report on Eastern Democratic Republic of the Congo

    Energy Technology Data Exchange (ETDEWEB)

    Warren, Tracy A [ORNL

    2011-05-01

    Each month, approximately 45,000 people die from violence, hunger, disease, and other effects of displacement as a result of war in the Democratic Republic of the Congo (DRC). The country is often said to be plagued by a 'resource curse.' During each period in history since its discovery by the West, the DRC has possessed the resources the world craves and the world has sought these without regard for the consequences to the Congolese people. The catastrophic consequences of Congo's history of natural resource exploitation are the direct and indirect death of millions of Congolese people. The current war in Congo is multi-causal in nature but explanations are often reduced to describing it as an ethic conflict based on objective grievance. Objective grievance such as inequality, ethnic tensions, land disputes, and lack of democracy do exist, but they are neither necessary nor sufficient to explain the cause of the violent conflict, and more importantly, they fall short in explaining why this conflict has continued for years. The reality is the conflict is an economic war in which the trade of conflict minerals, gold and the 3Ts (tin, tantalum, tungsten), is directly linked to the financial sustainability of the groups fighting each other in eastern DRC. Objective grievance is a by-product of the conflict, used to create a false but plausible moral justification to continue violence. This paper examines the history of conflict in the DRC and the socio-economic variables contributing to the current war fought over conflict minerals.

  11. Molecular Insights into Crimean-Congo Hemorrhagic Fever Virus

    Directory of Open Access Journals (Sweden)

    Marko Zivcec

    2016-04-01

    Full Text Available Crimean-Congo hemorrhagic fever virus (CCHFV is a tick-borne pathogen that causes high morbidity and mortality. Efficacy of vaccines and antivirals to treat human CCHFV infections remains limited and controversial. Research into pathology and underlying molecular mechanisms of CCHFV and other nairoviruses is limited. Significant progress has been made in our understanding of CCHFV replication and pathogenesis in the past decade. Here we review the most recent molecular advances in CCHFV-related research, and provide perspectives on future research.

  12. Forest crimes as a threat to sustainable forest management

    Directory of Open Access Journals (Sweden)

    S. Özden

    2016-08-01

    decrease of forest crimes in rural areas. On the other hand, legal and illegal forest attacks have been increasing due to urbanization in this process. This study was conducted to evaluate Yeşilirmak river basin forest crimes of the last 11 years. Yeşilirmak river basin occupies 3 964 375 ha, which is approximately 5 % of Turkey’s total area and 519 km in length.

  13. Autonomy, Equality, and Teaching among Aka Foragers and Ngandu Farmers of the Congo Basin.

    Science.gov (United States)

    Boyette, Adam H; Hewlett, Barry S

    2017-09-01

    The significance of teaching to the evolution of human culture is under debate. We contribute to the discussion by using a quantitative, cross-cultural comparative approach to investigate the role of teaching in the lives of children in two small-scale societies: Aka foragers and Ngandu farmers of the Central African Republic. Focal follows with behavior coding were used to record social learning experiences of children aged 4 to 16 during daily life. "Teaching" was coded based on a functional definition from evolutionary biology. Frequencies, contexts, and subtypes of teaching as well as the identity of teachers were analyzed. Teaching was rare compared to observational learning, although both forms of social learning were negatively correlated with age. Children received teaching from a variety of individuals, and they also engaged in teaching. Several teaching types were observed, including instruction, negative feedback, and commands. Statistical differences in the distribution of teaching types and the identity of teachers corresponded with contrasting forager vs. farmer foundational cultural schema. For example, Aka children received less instruction, which empirically limits autonomous learning, and were as likely to receive instruction and negative feedback from other children as they were from adults. Commands, however, exhibited a different pattern suggesting a more complex role for this teaching type. Although consistent with claims that teaching is relatively rare in small-scale societies, this evidence supports the conclusion that teaching is a universal, early emerging cognitive ability in humans. However, culture (e.g., values for autonomy and egalitarianism) structures the nature of teaching.

  14. The effects of climate change in the Congo basin: The need to ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-04-22

    Apr 22, 2016 ... ... in three countries — Cameroon, the Central African Republic, and the Democratic ... This brief resulted from two projects from the Climate Change Adaptation in Africa program: the research ... Testing perceptions about water in Lebanon and Jordan ... Despite the availability of more reliable forecasts from ...

  15. Flow-specific trends in river-water quality resulting from the effects of the clean air act in three mesoscale, forested river basins in the northeastern United States through 2002

    Science.gov (United States)

    Murdoch, Peter S.; Shanley, J.B.

    2006-01-01

    Two new methods for assessing temporal trends in stream-solute concentrations at specific streamflow ranges were applied to long (40 to 50-year) but sparse (bi-weekly to quarterly sampling) stream-water quality data collected at three forested mesoscale basins along an atmospheric deposition gradient in the northeastern United States (one in north-central Pennsylvania, one in southeastern New York, and one in eastern Maine). The three data sets span the period since the implementation of the Clean Air Act in 1970 and its subsequent amendments. Declining sulfate (SO2-4) trends since the mid 1960s were identified for all 3 rivers by one or more of the 4 methods of trend detection used. Flow-specific trends were assessed by segmenting the data sets into 3-year and 6-year blocks, then determining concentration-discharge relationships for each block. Declining sulfate (SO2-4) trends at median flow were similar to trends determined using a Seasonal Kendall Tau test and Sen slope estimator. The trend of declining SO2-4 concentrations differed at high, median and low flow since the mid 1980s at YWC and NR, and at high and low flow at WR, but the trends leveled or reversed at high flow from 1999 through 2002. Trends for the period of record at high flows were similar to medium- and low-flow trends for Ca2+ + Mg2+ concentrations at WR, non-significant at YWC, and were more negative at low flow than at high flow at NR; trends in nitrate (NO-3), and alkalinity (ALK) concentrations were different at different flow conditions, and in ways that are consistent with the hydrology and deposition history at each watershed. Quarterly sampling is adequate for assessing average-flow trends in the chemical parameters assessed over long time periods (???decades). However, with even a modest effort at sampling a range of flow conditions within each year, trends at specified flows for constituents with strong concentration-discharge relationships can be evaluated and may allow early

  16. Forest rights

    DEFF Research Database (Denmark)

    Balooni, Kulbhushan; Lund, Jens Friis

    2014-01-01

    One of the proposed strategies for implementation of reducing emissions from deforestation and forest degradation plus (REDD+) is to incentivize conservation of forests managed by communities under decentralized forest management. Yet, we argue that this is a challenging road to REDD+ because...... conservation of forests under existing decentralized management arrangements toward a push for extending the coverage of forests under decentralized management, making forest rights the hard currency of REDD+....

  17. Inventaire préliminaire de la faune lombricienne dans la Réserve et Domaine de Chasse de Bombo-Lumene, plateaux Batéké (République Démocratique du Congo

    Directory of Open Access Journals (Sweden)

    Milau, F.

    2018-01-01

    Full Text Available Preliminary Inventory of the Earthworm Fauna in the "Réserve et Domaine de chasse" of Bombo-Lumene Batéké Plateau (Democratic Republic of the Congo. The soil macrofauna is frequently cited for its important role in the physicochemical parameters of cultivated land. Moreover, the tillage frequency and the cropping intensity are key factors to be considered in the management of cropping systems. An inventory related to the changes in land use on the earthworm fauna was carried out. The diversity and the abundance of the harvested species were determined in savannah and in forest ecosystems. The study was conducted in the "Réserve et Domaine de chasse" of Bombo-Lumene located on Batéké Plateau in the Democratic Republic of the Congo. Six types of environments have been prospected: semi-deciduous dense forests, gallery forests, second-growth forests, grasslands, woodland savannas, and crop land. Collected earthworm species are presented according to their habitat, their feeding habit, the kind of prostomium, and their geographical distribution.

  18. Avaliação multicriterial no mapeamento de risco de incêndios florestais, em ambiente sig, na bacia do Rio Corumbataí, SP Multi-criteria evaluation of a GIS environment in a forest fire hazard mapping for the Corumbataí River basin, SP, Brazil

    Directory of Open Access Journals (Sweden)

    Hilton Luis Ferraz da Silveira

    2008-04-01

    Full Text Available Um dos agentes mais empregados na supressão de áreas florestais no Estado de São Paulo é o fogo, por meio de queimadas que, quando fora de controle, podem converter-se em incêndios responsáveis pela destruição de extensos ecossistemas. Na Bacia do Rio Corumbataí, SP, os incêndios são um dos causadores de fragmentação e degradação da cobertura florestal. Nesse contexto, este trabalho objetivou a realização do mapeamento de risco de incêndios florestais na Bacia do Rio Corumbataí, utilizando-se a avaliação multicriterial (Método da Média Ponderada Ordenada em um Sistema de Informações Geográficas. Os fatores importantes do estudo foram: declividade do terreno, face de exposição ao sol, pluviosidade, proximidade da malha viária, proximidade dos centros urbanos, proximidade da rede hidrográfica, vizinhança dos fragmentos e face de exposição aos ventos. A combinação dos mapas de fatores resultou no mapa de risco regional da bacia. Para a confecção do mapa de risco em nível de fragmento, determinou-se o risco associado a cada fragmento, a partir da análise de uma faixa de 30 m em seu entorno. O risco foi reclassificado em três classes: baixo, médio e alto. Com base no mapa final, verificou-se que: aproximadamente 20% dos fragmentos de mata nativa pertencem à classe de risco alto, 55% à classe de risco médio e 25% à classe de risco baixo. Nas condições atuais de uso e cobertura do solo, bem como de manejo das áreas agrícolas e pastagens, os remanescentes florestais da Bacia do Rio Corumbataí estão sob séria ameaça de degradação por incêndios florestais.Fire is one of the agents most used in the suppression of forest areas in the State of São Paulo, Brazil, and, when out of control, it can be responsible for the destruction of extensive ecosystems. In the case of the Corumbataí river basin, SP, fire is one of the main causes of forest fragmentation and degradation. The purpose of this study was

  19. Residual basins

    International Nuclear Information System (INIS)

    D'Elboux, C.V.; Paiva, I.B.

    1980-01-01

    Exploration for uranium carried out over a major portion of the Rio Grande do Sul Shield has revealed a number of small residual basins developed along glacially eroded channels of pre-Permian age. Mineralization of uranium occurs in two distinct sedimentary units. The lower unit consists of rhythmites overlain by a sequence of black shales, siltstones and coal seams, while the upper one is dominated by sandstones of probable fluvial origin. (Author) [pt

  20. All projects related to | Page 497 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2008-01-07

    The forests of the Congo basin provide ecosystem services to over 80% of the population living in or near them. Start Date: January 7, 2008. End Date: May 18, 2012. Topic: CLIMATE CHANGE, ADAPTATION TO CHANGE, RIVER BASINS, FOREST RESOURCES, FOREST POLICY, FOREST MANAGEMENT, FOREST ...

  1. All projects related to | Page 496 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2008-01-07

    The forests of the Congo basin provide ecosystem services to over 80% of the population living in or near them. Start Date: January 7, 2008. End Date: May 18, 2012. Topic: CLIMATE CHANGE, ADAPTATION TO CHANGE, RIVER BASINS, FOREST RESOURCES, FOREST POLICY, FOREST MANAGEMENT, FOREST ...

  2. Reaction of congo red in water after irradiation by pulsed intense relativistic electron beam

    International Nuclear Information System (INIS)

    Kikuchi, Takashi; Kondo, Hironobu; Sasaki, Toru; Harada, Nob.; Moriwaki, Hiroshi; Nakanishi, Hiromitsu; Imada, Go

    2011-01-01

    The reaction of congo red, a well-known toxic azo dye, occurred after irradiation by a pulsed intense relativistic electron beam (PIREB). An aquation of congo red was irradiated by PIREB (2 MeV, 0.36 kA, 140 ns). After PIREB irradiation, the solution was measured by electrospray ionization-mass spectrometry and liquid chromatography/mass spectrometry. It was found that congo red underwent a reaction (77% conversion after five shots of PIREB irradiation) and the hydroxylated compounds of the dye were observed as reaction products. (author)

  3. Adsorption of procion red and congo red dyes using microalgae Spirulina sp

    Directory of Open Access Journals (Sweden)

    Risfidian Mohadi

    2017-10-01

    Full Text Available Adsorption of procion red and congo red dyes using microalgae Spirulina sp was conducted. Spirulina sp was obtained by cultivation and production in laboratory scale. Spirulina sp was used as adsorbent for adsorption of dyes. Adsorption process was studied by kinetic and thermodynamic in order to know the adsorption phenomena. The results showed that kinetically congo red is reactive than procion red on Spirulina sp. On the other hand, thermodynamically procion red was stable than congo red on Spirulina sp which was indicated by adsorption capacity, enthalpy, and entropy.

  4. The use of an agricultural waste material, Jujuba seeds for the removal of anionic dye (Congo red) from aqueous medium

    International Nuclear Information System (INIS)

    Somasekhara Reddy, M.C.; Sivaramakrishna, L.; Varada Reddy, A.

    2012-01-01

    Highlights: ► We have introduced a low-cost, abundantly locally available non-conventional adsorbent in place of activated carbons. ► The kinetic data were well described by second order kinetic model and intra-particle diffusion model. ► The Langmuir and generalized isotherm models were the best fitting for the isotherm results. ► Removal capacity of Jujuba seeds is more than so many agricultural wastes. ► Relative cost of Jujuba seeds for the removal of Congo red can be compared with activated carbons - Abstract: The feasibility of using Indian Jujuba Seeds (IJS) (Zizyphus maruritiana), abundantly available in and around the Nallamalla forest in Andhra Pradesh, for the anionic dye (Congo red, CR) adsorption from aqueous solution, has been investigated as low cost and eco-friendly adsorbent. Adsorption studies were conducted on a batch process, to study the effects of contact time, initial concentration of CR, pH and temperature. Maximum colour removal was observed at pH 2. The equilibrium data was analyzed by the Langmuir, the Freundlich and the General isotherms. The data fitted well with the Langmuir model, with a maximum adsorption capacity of 55.56 mg g −1 . The pseudo-second-order kinetics was the best for the adsorption of CR, by IJS (Z. maruritiana) with good correlation. Thermodynamic parameters, such as standard free energy change (ΔG°), standard enthalpy change (ΔH°) and standard entropy change (ΔS°), were analyzed. The results suggest that IJS (Z. maruritiana) is a potential low-cost adsorbent for the CR dye removal from synthetic dye wastewater.

  5. Evapotranspiration seasonality across the Amazon Basin

    Science.gov (United States)

    Eiji Maeda, Eduardo; Ma, Xuanlong; Wagner, Fabien Hubert; Kim, Hyungjun; Oki, Taikan; Eamus, Derek; Huete, Alfredo

    2017-06-01

    Evapotranspiration (ET) of Amazon forests is a main driver of regional climate patterns and an important indicator of ecosystem functioning. Despite its importance, the seasonal variability of ET over Amazon forests, and its relationship with environmental drivers, is still poorly understood. In this study, we carry out a water balance approach to analyse seasonal patterns in ET and their relationships with water and energy drivers over five sub-basins across the Amazon Basin. We used in situ measurements of river discharge, and remotely sensed estimates of terrestrial water storage, rainfall, and solar radiation. We show that the characteristics of ET seasonality in all sub-basins differ in timing and magnitude. The highest mean annual ET was found in the northern Rio Negro basin (˜ 1497 mm year-1) and the lowest values in the Solimões River basin (˜ 986 mm year-1). For the first time in a basin-scale study, using observational data, we show that factors limiting ET vary across climatic gradients in the Amazon, confirming local-scale eddy covariance studies. Both annual mean and seasonality in ET are driven by a combination of energy and water availability, as neither rainfall nor radiation alone could explain patterns in ET. In southern basins, despite seasonal rainfall deficits, deep root water uptake allows increasing rates of ET during the dry season, when radiation is usually higher than in the wet season. We demonstrate contrasting ET seasonality with satellite greenness across Amazon forests, with strong asynchronous relationships in ever-wet watersheds, and positive correlations observed in seasonally dry watersheds. Finally, we compared our results with estimates obtained by two ET models, and we conclude that neither of the two tested models could provide a consistent representation of ET seasonal patterns across the Amazon.

  6. Forest soils

    Science.gov (United States)

    Charles H. (Hobie) Perry; Michael C. Amacher

    2009-01-01

    Productive soils are the foundation of sustainable forests throughout the United States. Forest soils are generally subjected to fewer disturbances than agricultural soils, particularly those that are tilled, so forest soils tend to have better preserved A-horizons than agricultural soils. Another major contrast between forest and agricultural soils is the addition of...

  7. Forest hydrology

    Science.gov (United States)

    Ge Sun; Devendra Amatya; Steve McNulty

    2016-01-01

    Forest hydrology studies the distribution, storage, movement, and quality of water and the hydrological processes in forest-dominated ecosystems. Forest hydrological science is regarded as the foundation of modern integrated water¬shed management. This chapter provides an overview of the history of forest hydrology and basic principles of this unique branch of...

  8. Forest Management

    Science.gov (United States)

    S. Hummel; K. L. O' Hara

    2008-01-01

    Global variation in forests and in human cultures means that a single method for managing forests is not possible. However, forest management everywhere shares some common principles because it is rooted in physical and biological sciences like chemistry and genetics. Ecological forest management is an approach that combines an understanding of universal processes with...

  9. Alimentación de Microthrissa congica (Osteichthyes: Clupeidae en la cuenca alta del río Congo (África

    Directory of Open Access Journals (Sweden)

    Godefroid Mambyanga Mokoma

    1999-12-01

    Full Text Available Mensualmente durante un año, se estudió la alimentación de Microthrissa congica en la cuenca alta del Río Congo, mediante el análisis de contenidos estomacales de ejemplares adultos. De acuerdo con la frecuencia de aparición, las ninfas de quironómidos constituyen la base de su alimentación durante todo el año. La importancia de los insectos de origen terrestre aumenta durante la época de lluvias, momento en que aumenta la amplitud del nicho. Estos resultados demuestran que este clupeido es una especie insectívora pelágica, utilizando muy poco el bentos como fuente de alimento.The feeding habits of the fish Microthrissa congica were studied for a year in the upper Congo river basin, by monthly analysis of stomach contents of adult specimens (N= 460. The nymphs of chironomid midges represented the bulk of the diet throughout most of the year, although terrestrial insects became more abundant in the rainy season. Niche breadth also increased in the wet season. This species feeds mainly in the water column and benthos is not an important food source.

  10. Fishes of the White River basin, Indiana

    Science.gov (United States)

    Crawford, Charles G.; Lydy, Michael J.; Frey, Jeffrey W.

    1996-01-01

    Since 1875, researchers have reported 158 species of fish belonging to 25 families in the White River Basin. Of these species, 6 have not been reported since 1900 and 10 have not been reported since 1943. Since the 1820's, fish communities in the White River Basin have been affected by the alteration of stream habitat, overfishing, the introduction of non-native species, agriculture, and urbanization. Erosion resulting from conversion of forest land to cropland in the 1800's led to siltation of streambeds and resulted in the loss of some silt-sensitive species. In the early 1900's, the water quality of the White River was seriously degraded for 100 miles by untreated sewage from the City of Indianapolis. During the last 25 years, water quality in the basin has improved because of efforts to control water pollution. Fish communities in the basin have responded favorably to the improved water quality.

  11. [Population planning unit is developed in the Congo].

    Science.gov (United States)

    Amouali, C; Poukouta, P

    1989-01-01

    This article is an update on the demographic situation in the Congo and the institutionalization of a population unit in The Ministry of Plan. From 1974-84 the population increased 44.9% going from 1,319,790 to 1,912,429 at a growth rate of 3.48% and possibly doubling in 20 years (2005). However, the major transformation has been the growth of the urban areas over the rural. From 1974-84 the rural population went from 819,430 to 934,849 while the urban population went from 500,360 in 1974 to 977,580 in 1984. The growth rate of the rural areas was 1.22% while that for the urban was 6.38% Infant mortality rate stands at 73/1000; life expectancy is 46.9 for men and 50.0 for women. The average fertility rate is 6. This demographic situation with the inherent problems of the rapidly growing urbanization of the 2 principal cities, Brazzaville and Pointe-Noire, has led to problems in health services and high morbidity and mortality rates. The Government has created 3 national organizations to coordinate population activities in the country: 1) The National Council on Population, (1988) an interministerial council, presided over by the Prime Minister, that defines and formulates national population policies as integral components to the country's socioeconomic development plans; 2) The National Commission on Population (CONAPO), headed by the Minister of Plan, Finance and Economics as the administrative organ of The National Council on Population, and responsible for the technical and evaluation activities of The National Council on Population; and 3) The Population Planning Unit headed by the Director of Human Resources in the Ministry of Plan responsible for identifying, formulating and evaluating population policies in the Congo. These institutions were created as a result of the 1974 Bucharest Conference and the 1984 Arusha Conference were population and development were considered integral components, and of results of 2 censuses and population surveys highlighting

  12. Composição e configuração da paisagem da sub-bacia do arroio jacaré, Vale do Taquari, RS, com ênfase nas áreas de florestas Landscape composition and configuration of jacaré stream sub-basin, Taquari Valley, RS, with emphasis on the forest areas

    Directory of Open Access Journals (Sweden)

    Gisele Cemin

    2009-08-01

    Full Text Available A conversão de áreas com cobertura florestal contínua por fragmentos florestais vem contribuindo para a diminuição da diversidade biológica, em função da perda de micro-habitats únicos, mudanças nos padrões de dispersão e migração, isolamento de habitats e erosão do solo. A solução desses problemas está intimamente vinculada ao planejamento e manutenção de bacias hidrográficas. A sub-bacia do Arroio Jacaré, localizada no Vale do Taquari, RS, compreende uma área de 538,98 km², onde estão parcial ou totalmente inseridos nove municípios. Essa bacia se encontra em uma região de ecótono entre as formações vegetais do tipo Floresta Estacional Decidual (FED e Floresta Ombrófila Mista - Mata de Araucária (FOM. Foram elaboradas e analisadas informações relacionadas às características estruturais das classes de mata na região (FED, FOM e vegetação secundária, utilizando-se imagem do satélite Landsat 7 ETM+, referente à passagem 04/02/2002 e software de Sistemas de Informações Geográficas (SIG Idrisi, 3.2, software de Ecologia de Paisagem Fragstats 3.3. Os resultados indicaram que a região apresenta aproximadamente 50% de suas matas nativas conservadas ou em estágio de regeneração, porém de forma altamente fragmentada, com 87,82% dos fragmentos menores que 1 ha. Considerando um efeito de borda de 50 m, em torno de 40% dos fragmentos ainda apresentam área nuclear.The conversion of continuous forest coverage areas into forest fragments has contributed to the decrease of the biological diversity due to the micro-habitat loss, changes in dispersion and migration patterns, habitats' isolation and soil erosion. The solution for those problems is intimately linked to the planning and maintenance of hydrographic basins. Jacaré's stream sub-basin is located in Taquari Valley, RS, with an area of 538,98 km², where nine municipal districts are partially or totally inserted. This basin is in an ecotone area among

  13. Alchornea cordifolia (Schumach. & Thonn.) Muell. Arg. (Euphorbiaceae), a disjunct Guineo-Congolian tree found in Ethiopia as dominant in riverine forest

    DEFF Research Database (Denmark)

    Friis, Ib; Harris, Timothy

    2013-01-01

    The small Guineo-Congolian tree Alchornea cordifolia (Euphorbiaceae) has been observed to dominate the undergrowth in an open type of southwest Ethiopian riverine forest not recorded before. The nearest previously known records of this species were at the South Sudan–Congo border and in Uganda...

  14. Discharge and other hydraulic measurements for characterizing the hydraulics of Lower Congo River

    Science.gov (United States)

    Oberg, Kevin; Shelton, John M.; Gardiner, Ned; Jackson, P. Ryan

    2009-01-01

    The first direct measurements of discharge of the Lower Congo River below Malebo Pool and upstream from Kinganga, Democratic Republic of Congo (DRC) were made in July 2008 using acoustic Doppler current profilers, differential GPS, and echo sounders. These measurements were made in support of research that is attempting to understand the distribution of fish species in the Lower Congo River and reasons for separation of species within this large river. Analyses of these measurements show that the maximum depth in the Lower Congo River was in excess of 200 m and maximum water velocities were greater than 4 m/s. The discharge measured near Luozi, DRC was 35,800 m3/s, and decreased slightly beginning midway through the study. Local bedrock controls seem to have a large effect on the flow in the river, even in reaches without waterfalls and rapids. Dramatic changes in bed topography are evident in transects across the river.

  15. Ebola Virus Disease, Democratic Republic of the Congo, 2014.

    Science.gov (United States)

    Nanclares, Carolina; Kapetshi, Jimmy; Lionetto, Fanshen; de la Rosa, Olimpia; Tamfun, Jean-Jacques Muyembe; Alia, Miriam; Kobinger, Gary; Bernasconi, Andrea

    2016-09-01

    During July-November 2014, the Democratic Republic of the Congo underwent its seventh Ebola virus disease (EVD) outbreak. The etiologic agent was Zaire Ebola virus; 66 cases were reported (overall case-fatality rate 74.2%). Through a retrospective observational study of confirmed EVD in 25 patients admitted to either of 2 Ebola treatment centers, we described clinical features and investigated correlates associated with death. Clinical features were mainly generic. At admission, 76% of patients had >1 gastrointestinal symptom and 28% >1 hemorrhagic symptom. The case-fatality rate in this group was 48% and was higher for female patients (67%). Cox regression analysis correlated death with initial low cycle threshold, indicating high viral load. Cycle threshold was a robust predictor of death, as were fever, hiccups, diarrhea, dyspnea, dehydration, disorientation, hematemesis, bloody feces during hospitalization, and anorexia in recent medical history. Differences from other outbreaks could suggest guidance for optimizing clinical management and disease control.

  16. Second International Conference on Crimean-Congo Hemorrhagic Fever.

    Science.gov (United States)

    Spengler, Jessica R; Bente, Dennis A; Bray, Mike; Burt, Felicity; Hewson, Roger; Korukluoglu, Gülay; Mirazimi, Ali; Weber, Friedemann; Papa, Anna

    2018-02-01

    The Second International Conference on Crimean-Congo Hemorrhagic Fever (CCHF) was held in Thessaloniki, Greece, from September 10-13, 2017, and brought together international public health professionals, clinicians, ecologists, and basic laboratory researchers. Nearly 100 participants, representing 24 countries and the World Health Organization (WHO), were in attendance. Meeting sessions covered the epidemiology of CCHF in humans; ticks and virus-tick interactions; wild and domestic animal hosts; molecular virology; taxonomic classification; pathogenesis and animal models; clinical aspects and diagnosis; clinical management and clinical trials; and disease prevention in humans. The concluding session focused on recent WHO recommendations for public health measures and future research. This report summarizes lectures by the invited speakers and highlights advances in the field. Copyright © 2017. Published by Elsevier B.V.

  17. Cold-seep-like macrofaunal communities in organic- and sulfide-rich sediments of the Congo deep-sea fan

    Science.gov (United States)

    Olu, K.; Decker, C.; Pastor, L.; Caprais, J.-C.; Khripounoff, A.; Morineaux, M.; Ain Baziz, M.; Menot, L.; Rabouille, C.

    2017-08-01

    Methane-rich fluids arising from organic matter diagenesis in deep sediment layers sustain chemosynthesis-based ecosystems along continental margins. This type of cold seep develops on pockmarks along the Congo margin, where fluids migrate from deep-buried paleo-channels of the Congo River, acting as reservoirs. Similar ecosystems based on shallow methane production occur in the terminal lobes of the present-day Congo deep-sea fan, which is supplied by huge quantities of primarily terrestrial material carried by turbiditic currents along the 800 km channel, and deposited at depths of up to nearly 5000 m. In this paper, we explore the effect of this carbon enrichment of deep-sea sediments on benthic macrofauna, along the prograding lobes fed by the current active channel, and on older lobes receiving less turbiditic inputs. Macrofaunal communities were sampled using either USNEL cores on the channel levees, or ROV blade cores in the chemosynthesis-based habitats patchily distributed in the active lobe complex. The exceptionally high organic content of the surface sediment in the active lobe complex was correlated with unusual densities of macrofauna for this depth, enhanced by a factor 7-8, compared with those of the older, abandoned lobe, whose sediment carbon content is still higher than in Angola Basin at same depth. Macrofaunal communities, dominated by cossurid polychaetes and tanaids were also more closely related to those colonizing low-flow cold seeps than those of typical deep-sea sediment. In reduced sediments, microbial mats and vesicomyid bivalve beds displayed macrofaunal community patterns that were similar to their cold-seep counterparts, with high densities, low diversity and dominance of sulfide-tolerant polychaetes and gastropods in the most sulfidic habitats. In addition, diversity was higher in vesicomyid bivalve beds, which appeared to bio-irrigate the upper sediment layers. High beta-diversity is underscored by the variability of geochemical

  18. Crimean-Congo Haemorrhagic Fever in Kosova : a fatal case report

    Directory of Open Access Journals (Sweden)

    Raka Lul

    2006-10-01

    Full Text Available Abstract Crimean-Congo haemorrhagic fever (CCHF is an often fatal viral infection described in about 30 countries around the world. The authors report a fatal case of Crimean-Congo hemorrhagic fever (CCHF observed in a patient from Kosova. The diagnosis of CCHF was confirmed by reverse transcription-PCR. Late diagnosis decreased the efficacy of treatment and patient died due to severe complications of infection.

  19. Democratic Republic of Congo A Fertile Ground for Instability in the Great Lakes Region States

    Science.gov (United States)

    2017-06-09

    ravaged by a brutal armed conflict. In comparison to the three past presidents, Joseph Kabila has managed to restore political stability and calm to much...DEMOCRATIC REPUBLIC OF CONGO-A FERTILE GROUND FOR INSTABILITY IN THE GREAT LAKES REGION STATES A thesis presented to the Faculty of...From - To) AUG 2016 – JUNE 2017 4. TITLE AND SUBTITLE Democratic Republic of Congo-A Fertile Ground for Instability in the Great Lakes Region

  20. Geologic characterization of Cuvette Centrale petroleum systems Congo-DRC

    Energy Technology Data Exchange (ETDEWEB)

    Vicentelli, Maria Gabriela C.; Barbosa, Mauro; Rezende, Nelio G.A.M. [HRT Petroleum, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The Cuvette Centrale is an almost unexplored basin, which contains some petroleum system elements that indicate the presence of hydrocarbons. In this sense; this paper presents an exploratory alternative for this intracratonic basin. The interpretation of the limited gravimetric, magnetometric, geochemical and seismic available data allowed the identification of many huge structural features and also some areas with hydrocarbon potential for stratigraphic traps. The presence of several oil and gas seeps widespread around the Busira and Lokoro sub-basins indicate that at least one active petroleum system exist in the basin. Despite only four wells have been drilled in the basin, one of them presented oil shows during drilling. Geological correlations between Brazilian Paleozoic basins and Cuvette Centrale sedimentary sequences permitted to conclude that Cambro-Ordovician and Siluro-Devonian source rocks must be present and active in the Cuvette Centrale basin. The tectono-stratigraphic evolution history of the Cuvette Centrale from Neo proterozoic to Recent times shows extensional and compressional/transpressional alternating phases along the geological time. The most confident petroleum system expected in the Cuvette Centrale is characterized by the Cambrian Mamungi shale - source rock - and the Cambro-Ordovician. Upper Arenaceous Sequence - reservoirs, as observed in the MBandaka and Gilson wells and confirmed by surface geology in outcrops. Besides, other potential petroleum systems are expected to occur in the basin. One is characterized by the Neo proterozoic Itury Group source rock and reservoirs in the mature/over mature stage, the others are the Siluro-Devonian and Cretaceous source rocks and reservoirs, expected to occur with better maturity conditions only in the deeper parts of the basin. (author)

  1. Extending WEPP technology to predict fine sediment and phosphorus delivery from forested hillslopes

    Science.gov (United States)

    William Elliot; Erin Brooks; Drea Em Traeumer; Mariana Dobre

    2015-01-01

    In many watersheds, including the Great Lakes and Lake Tahoe Basins, two basins where the land cover is dominated by forests, the pollutants of concern are fine sediments and phosphorus. Forest runoff is generally low in nitrogen, and coarse sediment does not adversely impact the quality of lake waters. Predictive tools are needed to estimate not simply sediment, but...

  2. Congo grass grown in rotation with soybean affects phosphorus bound to soil carbon

    Directory of Open Access Journals (Sweden)

    Alexandre Merlin

    2014-06-01

    Full Text Available The phosphorus supply to crops in tropical soils is deficient due to its somewhat insoluble nature in soil, and addition of P fertilizers has been necessary to achieve high yields. The objective of this study was to examine the mechanisms through which a cover crop (Congo grass - Brachiaria ruziziensis in rotation with soybean can enhance soil and fertilizer P availability using long-term field trials and laboratory chemical fractionation approaches. The experimental field had been cropped to soybean in rotation with several species under no-till for six years. An application rate of no P or 240 kg ha-1 of P2O5 had been applied as triple superphosphate or as Arad rock phosphate. In April 2009, once more 0.0 or 80.0 kg ha-1 of P2O5 was applied to the same plots when Congo grass was planted. In November 2009, after Congo grass desiccation, soil samples were taken from the 0-5 and 5-10 cm depth layer and soil P was fractionated. Soil-available P increased to the depth of 10 cm through growing Congo grass when P fertilizers were applied. The C:P ratio was also increased by the cover crop. Congo grass cultivation increased P content in the soil humic fraction to the depth of 10 cm. Congo grass increases soil P availability by preventing fertilizer from being adsorbed and by increasing soil organic P.

  3. The influence of Congo River discharges in the surface and deep layers of the Gulf of Guinea

    OpenAIRE

    Vangriesheim, A.; Pierre, C.; Aminot, A.; Metzl, N.; Baurand, François; Caprais, J. C.

    2009-01-01

    The main feature of the Congo-Angola margin in the Gulf of Guinea is the Congo (ex-Zaire) deep-sea fan composed of a submarine canyon directly connected to the Congo River, a channel and a [sediment] lobe area. During the multi-disciplinary programme called BIOZAIRE conducted by Ifremer from 2000 to 2005, two CTD-O2 sections with discrete water column samples were performed (BIOZAIRE3 cruise: 2003-2004) to study the influence of the Congo River discharges, both in the surface layer and in the...

  4. Modeling climate and fuel reduction impacts on mixed-conifer forest carbon stocks in the Sierra Nevada, California

    Science.gov (United States)

    Matthew D. Hurteau; Timothy A. Robards; Donald Stevens; David Saah; Malcolm North; George W. Koch

    2014-01-01

    Quantifying the impacts of changing climatic conditions on forest growth is integral to estimating future forest carbon balance. We used a growth-and-yield model, modified for climate sensitivity, to quantify the effects of altered climate on mixed-conifer forest growth in the Lake Tahoe Basin, California. Estimates of forest growth and live tree carbon stocks were...

  5. L’optimisation juridique du paiement pour services environnementaux en faveur de la préservation des services environnementaux : le cas du Cameroun et de la République Démocratique du Congo

    Directory of Open Access Journals (Sweden)

    Blaise-Pascal Ntirumenyerwa Mihigo

    2017-02-01

    Full Text Available The study starts from a hypothesis on the coherence and compatibility of the legal instruments in force in Cameroon and in the Democratic Republic of Congo (DRC with the optimization of payment for environmental services (PES and the preservation of environmental services. This study has employed a legal approach and interviews in order to investigate whether there is coherence and compatibility or not between the two variables of this hypothesis: (1 the legal instruments in force in Cameroon and in the DRC and (2 the optimization of PES and the preservation of environmental services. This study consists of three parts. The first part deals with the theoretical framework of PES and the place of PES in the legal order. In this first part, the definition of an optimal PES, the indicators of an optimal PES and the categories of legal frameworks on PES have been revealed. These are the fundamental elements to conduct a systematic analysis in the second and third parts. Based on these fundamental elements, the study analyses the legal instru- ments from international, regional (Africa and domestic (Cameroon and the DRC levels and investigates through field research two PES projects, one in Cameroon called “PES comminatory project” and another in the DRC called “REDD CBFF-Luki” respectively in the second and the third parts. From the analysis of these legal instruments and the investigation of these two PES projects, it has become apparent that there is a lack of coherence and compatibility between the legal instruments and these two PES projects in Cameroon and in the DRC, and the optimization of PES and the preservation of environmental services in the Congo Basin in general, especially in these two States. Useful recommendations have been made to eradicate these shortcomings. Key words: payment for environmental services, environmental services, Congo Basin

  6. Forest Resources

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

    Forest biomass is an abundant biomass feedstock that complements the conventional forest use of wood for paper and wood materials. It may be utilized for bioenergy production, such as heat and electricity, as well as for biofuels and a variety of bioproducts, such as industrial chemicals, textiles, and other renewable materials. The resources within the 2016 Billion-Ton Report include primary forest resources, which are taken directly from timberland-only forests, removed from the land, and taken to the roadside.

  7. Geochemistry of the Congo and Amazon river systems. Boron isotopic geochemistry in corals. Continental erosion and ocean pH

    International Nuclear Information System (INIS)

    Gaillardet, J.

    1995-01-01

    Two main geological processes control the CO 2 concentration in the atmosphere at a geological time scale: CO 2 outgasing from the interior of the Earth and CO 2 consumption by continental weathering. In the thesis, we initiate two different directions that can be useful to constraint the past climate evolution models. The first one is the extensive study of the largest rivers of the world using the classical geochemical analyses (major and trace elements, Sr-Nd-Pb isotopes) and modelling approaches. The study case of this thesis are the Congo and Amazon Basin. In particular, the coupling between chemical and physical erosion is examined and related to the hydrologic and tectonic parameters. Relief, thus tectonics appear to best control CO 2 consumption by rock weathering. The second part of the work is devoted to the measurement of boron isotopic ratio in corals because it may be used as a proxy for paleo-ocean pH. It could thus bring important pieces of information on the global C cycle and climate evolution. The technical part is extensively described and the method applied to the corals from the last interglacial period. Our conclusion is that corals are likely to be influence by early diagenetic changes that modify the boron isotopic composition of corals. We thus propose a test to select the samples. (author)

  8. FOREST DISTRIBUTION ON THE CENTRAL RUSSIAN UPLAND: HISTORICAL PERSPECTIVE

    Directory of Open Access Journals (Sweden)

    Maria V. Arkhipova

    2014-01-01

    Full Text Available We studied the change of forestland in the Central Russian Upland within the deciduous forest, forest-steppe, and steppe zones using old maps (XVIII-XX cc. and current satellite images. The forest distribution within the Central Russian Upland has been relatively stable during the last 220 years. On average, the decrease in the forested area was small. However, we identified significant changes in certain regions. In the southern part of CRU, the significant increase of the forested land is caused by the forest protection of abatis woodland and afforestation. During the last 100 years, reforestation took place mainly in the Oka basin due to both afforestation and natural reforestation. New forests appeared generally in ravines within all zones. The analysis of the abatis forests changes from the XVIII to XX cc. allowed us to identify forested area within the Central Russian Upland prior to active development.

  9. Skills of General Circulation and Earth System Models in reproducing streamflow to the ocean: the case of Congo river

    Science.gov (United States)

    Santini, M.; Caporaso, L.

    2017-12-01

    Although the importance of water resources in the context of climate change, it is still difficult to correctly simulate the freshwater cycle over the land via General Circulation and Earth System Models (GCMs and ESMs). Existing efforts from the Climate Model Intercomparison Project 5 (CMIP5) were mainly devoted to the validation of atmospheric variables like temperature and precipitation, with low attention to discharge.Here we investigate the present-day performances of GCMs and ESMs participating to CMIP5 in simulating the discharge of the river Congo to the sea thanks to: i) the long-term availability of discharge data for the Kinshasa hydrological station representative of more than 95% of the water flowing in the whole catchment; and ii) the River's still low influence by human intervention, which enables comparison with the (mostly) natural streamflow simulated within CMIP5.Our findings suggest how most of models appear overestimating the streamflow in terms of seasonal cycle, especially in the late winter and spring, while overestimation and variability across models are lower in late summer. Weighted ensemble means are also calculated, based on simulations' performances given by several metrics, showing some improvements of results.Although simulated inter-monthly and inter-annual percent anomalies do not appear significantly different from those in observed data, when translated into well consolidated indicators of drought attributes (frequency, magnitude, timing, duration), usually adopted for more immediate communication to stakeholders and decision makers, such anomalies can be misleading.These inconsistencies produce incorrect assessments towards water management planning and infrastructures (e.g. dams or irrigated areas), especially if models are used instead of measurements, as in case of ungauged basins or for basins with insufficient data, as well as when relying on models for future estimates without a preliminary quantification of model biases.

  10. Pechora River basin integrated system management PRISM; biodiversity assessment for the Pechora River basin; Cluster B: biodiversity, land use & forestry modeling

    NARCIS (Netherlands)

    Sluis, van der T.

    2005-01-01

    This report describes the biodiversity for the Pechora River basin Integrated System Management (PRISM). The Pechora River Basin, situated just west of the Ural Mountains, Russia, consists of vast boreal forests and tundra landscapes, partly pristine and undisturbed. The concept of biodiversity is

  11. Determination of Infrastructure Development in the Integrated Management Planning of Firtina Basin throug Participatary Approach

    Directory of Open Access Journals (Sweden)

    Cenap SANCAR

    2015-12-01

    Full Text Available Fırtına Basin (FB having natural temperate zone forests, rich biodiversity and high endemic variety is located in Caucasus Ecoregion which is among the most important 25 ecoregions on earth. Additionally, forest zones in FB are listed among “100 Forest Hotspots” in Europe by The World Conservation Monitoring Centre (UNEP WCMC. This study identified how and to what level existing land use pattern and related infrastructure, which compose basic inputs of sustainable basin management, influence ecology and biodiversity. Findings also revealed certain socio-economic and environmental effects of recent applications / projects which were not based on a holistic management plan. This study seeks to establish adequate technical infrastructure for the rational use and sustainable management of natural resources (water, soil, forest, etc. in Fırtına Basin and to provide coordination among the institutions. The Integrated Basin Management project also aims at designing a sustainable natural resource management and biodiversity conservation model for the piloting area, Fırtına Basin as well as for other basins. Moreover, IBM (Integrated Basin Management experiences will be opened to debate among scholars in academic and institutional circles who are also concerned with the basins in the same ecological corridor (Eastern Black Sea Mountains or other basins in the wider Caucasus Ecoregion.

  12. Stabilization of Aley river water content by forest stands

    Directory of Open Access Journals (Sweden)

    E. G. Paramonov

    2016-06-01

    Full Text Available Aley river basin is one of the most developed territories in West Siberia. Initially, the development here was related to the development of ore mining in the Altai. Currently it is associated mainly with the agricultural orientation of economic development. The intensive involvement of basin lands into the economic turnover for the last 100 years contributed to the formation of a number of environmental problems, such as water and wind erosion, loss of soil fertility and salinization, and desertification of the territory. Besides, the decrease of Aley river water content due to natural and anthropogenic reasons was observed. A specific feature of water management in Aley river basin is a significant amount of water resources used for irrigation purposes and agricultural water supply. To ensure the economic and drinking water supply, two reservoirs and a number of ponds have been constructed and operate in the basin. Forest ecosystems of the basin are considered from the viewpoint of preservation and restoration of small rivers. The ability of forest to accumulate solid precipitation and intercept them during the snowmelt for a longer time reduces the surface drainage and promotes transfer into the subsurface flow, significantly influencing the water content of permanent watercourses, is shown. The state of protective forest plantations in Aley river basin is analyzed. Aley river tributaries are compared by area, the length of water flow, and forest coverage of the basin. It is proposed to regulate the runoff through drastic actions on the increase of forest cover in the plain and especially in the mountainous parts of the basin. Measures to increase the forest cover within water protection zones, afforestation of temporary and permanent river basins, and the protection of agricultural soil fertility are worked out.

  13. Dominant effect of increasing forest biomass on evapotranspiration: interpretations of movement in Budyko space

    Science.gov (United States)

    Jaramillo, Fernando; Cory, Neil; Arheimer, Berit; Laudon, Hjalmar; van der Velde, Ype; Hasper, Thomas B.; Teutschbein, Claudia; Uddling, Johan

    2018-01-01

    During the last 6 decades, forest biomass has increased in Sweden mainly due to forest management, with a possible increasing effect on evapotranspiration. However, increasing global CO2 concentrations may also trigger physiological water-saving responses in broadleaf tree species, and to a lesser degree in some needleleaf conifer species, inducing an opposite effect. Additionally, changes in other forest attributes may also affect evapotranspiration. In this study, we aimed to detect the dominating effect(s) of forest change on evapotranspiration by studying changes in the ratio of actual evapotranspiration to precipitation, known as the evaporative ratio, during the period 1961-2012. We first used the Budyko framework of water and energy availability at the basin scale to study the hydroclimatic movements in Budyko space of 65 temperate and boreal basins during this period. We found that movements in Budyko space could not be explained by climatic changes in precipitation and potential evapotranspiration in 60 % of these basins, suggesting the existence of other dominant drivers of hydroclimatic change. In both the temperate and boreal basin groups studied, a negative climatic effect on the evaporative ratio was counteracted by a positive residual effect. The positive residual effect occurred along with increasing standing forest biomass in the temperate and boreal basin groups, increasing forest cover in the temperate basin group and no apparent changes in forest species composition in any group. From the three forest attributes, standing forest biomass was the one that could explain most of the variance of the residual effect in both basin groups. These results further suggest that the water-saving response to increasing CO2 in these forests is either negligible or overridden by the opposite effect of the increasing forest biomass. Thus, we conclude that increasing standing forest biomass is the dominant driver of long-term and large-scale evapotranspiration

  14. Dominant effect of increasing forest biomass on evapotranspiration: interpretations of movement in Budyko space

    Directory of Open Access Journals (Sweden)

    F. Jaramillo

    2018-01-01

    Full Text Available During the last 6 decades, forest biomass has increased in Sweden mainly due to forest management, with a possible increasing effect on evapotranspiration. However, increasing global CO2 concentrations may also trigger physiological water-saving responses in broadleaf tree species, and to a lesser degree in some needleleaf conifer species, inducing an opposite effect. Additionally, changes in other forest attributes may also affect evapotranspiration. In this study, we aimed to detect the dominating effect(s of forest change on evapotranspiration by studying changes in the ratio of actual evapotranspiration to precipitation, known as the evaporative ratio, during the period 1961–2012. We first used the Budyko framework of water and energy availability at the basin scale to study the hydroclimatic movements in Budyko space of 65 temperate and boreal basins during this period. We found that movements in Budyko space could not be explained by climatic changes in precipitation and potential evapotranspiration in 60 % of these basins, suggesting the existence of other dominant drivers of hydroclimatic change. In both the temperate and boreal basin groups studied, a negative climatic effect on the evaporative ratio was counteracted by a positive residual effect. The positive residual effect occurred along with increasing standing forest biomass in the temperate and boreal basin groups, increasing forest cover in the temperate basin group and no apparent changes in forest species composition in any group. From the three forest attributes, standing forest biomass was the one that could explain most of the variance of the residual effect in both basin groups. These results further suggest that the water-saving response to increasing CO2 in these forests is either negligible or overridden by the opposite effect of the increasing forest biomass. Thus, we conclude that increasing standing forest biomass is the dominant driver of long-term and large

  15. Investigation on the rapid degradation of congo red catalyzed by activated carbon powder under microwave irradiation

    International Nuclear Information System (INIS)

    Zhang Zhaohong; Shan Yabo; Wang Jun; Ling Hongjie; Zang Shuliang; Gao Wei; Zhao Zhe; Zhang Huachun

    2007-01-01

    Azo dyestuff-congo red in aqueous solution can be degraded rapidly under microwave irradiation in the presence of activated carbon powder. The results showed that the degradation ratio could reach 87.79% for 25 mL total volume with 50 mg/L congo red and 2.0 g/L activated carbon powder under 1.5 min microwave irradiation. Furthermore, within the same irradiation time, congo red could be degraded fully by increasing addition amount (e.g. 3.6 g/L) of activated carbon powder and the degradation ratio was up to 96.49%. Otherwise, with the same addition amount, congo red also could be degraded completely by prolonging irradiation time (e.g. 2.5 min) and the degradation ratio was up to 97.88%. In addition, the influences of microwave irradiation time, initial concentration of congo red, addition amount and used times of activated carbon powder as well as solution acidity on the degradation were discussed in details adopting UV-vis spectra, FT-IR spectra, ion chromatography, high phase liquid chromatography (HPLC) and TOC analysis technologies. Here, the method using activated carbon powder as catalyst under microwave irradiation shows many advantages including high degradation ratios, short reaction time, low costs, no intermediates and no secondary pollution. Therefore, it may be fit for dealing with various azo dyestuff wastewaters on a large scale

  16. Characteristic mega-basin water storage behavior using GRACE.

    Science.gov (United States)

    Reager, J T; Famiglietti, James S

    2013-06-01

    [1] A long-standing challenge for hydrologists has been a lack of observational data on global-scale basin hydrological behavior. With observations from NASA's Gravity Recovery and Climate Experiment (GRACE) mission, hydrologists are now able to study terrestrial water storage for large river basins (>200,000 km 2 ), with monthly time resolution. Here we provide results of a time series model of basin-averaged GRACE terrestrial water storage anomaly and Global Precipitation Climatology Project precipitation for the world's largest basins. We address the short (10 year) length of the GRACE record by adopting a parametric spectral method to calculate frequency-domain transfer functions of storage response to precipitation forcing and then generalize these transfer functions based on large-scale basin characteristics, such as percent forest cover and basin temperature. Among the parameters tested, results show that temperature, soil water-holding capacity, and percent forest cover are important controls on relative storage variability, while basin area and mean terrain slope are less important. The derived empirical relationships were accurate (0.54 ≤  E f  ≤ 0.84) in modeling global-scale water storage anomaly time series for the study basins using only precipitation, average basin temperature, and two land-surface variables, offering the potential for synthesis of basin storage time series beyond the GRACE observational period. Such an approach could be applied toward gap filling between current and future GRACE missions and for predicting basin storage given predictions of future precipitation.

  17. The state of emergency care in Democratic Republic of Congo

    Directory of Open Access Journals (Sweden)

    Luc Malemo Kalisya

    2015-12-01

    Full Text Available The Democratic Republic of Congo (DRC is the second largest country on the African continent with a population of over 70 million. It is also a major crossroad through Africa as it borders nine countries. Unfortunately, the DRC has experienced recurrent political and social instability throughout its history and active fighting is still prevalent today. At least two decades of conflict have devastated the civilian population and collapsed healthcare infrastructure. Life expectancy is low and government expenditure on health per capita remains one of the lowest in the world. Emergency Medicine has not been established as a specialty in the DRC. While the vast majority of hospitals have emergency rooms or salle des urgences, this designation has no agreed upon format and is rarely staffed by doctors or nurses trained in emergency care. Presenting complaints include general and obstetric surgical emergencies as well as respiratory and diarrhoeal illnesses. Most patients present late, in advanced stages of disease or with extreme morbidity, so mortality is high. Epidemics include HIV, cholera, measles, meningitis and other diarrhoeal and respiratory illnesses. Lack of training, lack of equipment and fee-for-service are cited as barriers to care. Pre-hospital care is also not an established specialty. New initiatives to improve emergency care include training Congolese physicians in emergency medicine residencies and medic ranger training within national parks.

  18. Crimean-Congo Hemorrhagic Fever: Tick-Host-Virus Interactions

    Directory of Open Access Journals (Sweden)

    Anna Papa

    2017-05-01

    Full Text Available Crimean-Congo hemorrhagic fever virus (CCHFV is transmitted to humans by bite of infected ticks or by direct contact with blood or tissues of viremic patients or animals. It causes to humans a severe disease with fatality up to 30%. The current knowledge about the vector-host-CCHFV interactions is very limited due to the high-level containment required for CCHFV studies. Among ticks, Hyalomma spp. are considered the most competent virus vectors. CCHFV evades the tick immune response, and following its replication in the lining of the tick's midgut, it is disseminated by the hemolymph in the salivary glands and reproductive organs. The introduction of salivary gland secretions into the host cells is the major route via which CCHFV enters the host. Following an initial amplification at the site of inoculation, the virus is spread to the target organs. Apoptosis is induced via both intrinsic and extrinsic pathways. Genetic factors and immune status of the host may affect the release of cytokines which play a major role in disease progression and outcome. It is expected that the use of new technology of metabolomics, transcriptomics and proteomics will lead to improved understanding of CCHFV-host interactions and identify potential targets for blocking the CCHFV transmission.

  19. Brucellosis in Patients with Crimean-Congo Hemorrhagic Fever

    Directory of Open Access Journals (Sweden)

    Fazilet Duygu

    2017-12-01

    Full Text Available Background: Crimean-Congo hemorrhagic fever (CCHF is a fatal zoonotic viral disease caused by infection with a tick-borne virus of the genus Nairovirus. In this study, we investigated the incidence of brucellosis in patients diag­nosed with CCHF.Methods: Overall, 169 patients hospitalized with an initial diagnosis of CCHF were included in 2011 in To­kat/ Turkey. Immunoglobulin M (IgM antibodies and/or PCR results were used in the laboratory diagnosis of CCHF, while plate and standard tube agglutination (STA tests were used to diagnose brucellosis.Results: Overall, 120 patients (79% with positive PCR tests were diagnosed with CCHF. Five (4.16% were also diag­nosed with brucellosis based on the positive plate and STA test results. Four patients (2.36% had negative CCHF PCR and positive STA test results.Conclusion: Brucellosis and CCHF can mimic each other and that all patients with CCHF or brucellosis should be screened for both conditions.

  20. [Hypertensive emergencies at the University Hospital Center in Brazzaville, Congo].

    Science.gov (United States)

    Ellenga, Mbolla B F; Gombet, T R; Mahoungou, Guimbi K C; Otiobanda, G F; Ossou, Nguiet P M; Ikama, M S; Kimbally-Kaky, G; Etitiele, F

    2011-02-01

    The purpose of this retrospective study conducted in the emergency department of the University Hospital Center in Brazzaville, Congo was to determine the prevalence and clinical characteristics of hypertensive emergencies. With a total of 76 patients admitted during the study period, the prevalence of hypertensive emergency was 4%. The sex ratio was 1 and mean patient age was 57.3 years (range, 30 to 80 years). Risk factors included obesity in 62 cases (81.6%), history of hypertension in 65 (85.5%) and low socioeconomic level in 58 (76.3%). Mean delay for consultation was 50 hours (range, 1 to 240 hours). The disease underlying the hypertensive emergency was stroke with 38 cases (50%), heart failure in 20 (26.3%), hypertensive encephalopathy in 11 (14.4%), malignant hypertension in 9 (11.8%), and renal failure in 10 (13.1%). The mean length of emergency treatment was 14.7 hours (range, 5 to 48 hours). Eight deaths (10.5%) occurred during hospitalization in the emergency department.

  1. Hepatitis in Patients with Crimean –Congo Hemorrhagic Fever

    Directory of Open Access Journals (Sweden)

    Batool Sharifi-Mood

    2014-04-01

    Full Text Available Background: Crimean–Congo hemorrhagic fever (CCHF is a viral disease and causing approximately 30% fatality rate. Recent studies have been reported that hepatitis in CCHF patients is with high mortality. The aim of this study was to determine the prevalence of hepatitis in the CCHF cases and also detect the mortality rate among patients with hepatitis. Materials and Methods: The present study was conducted in patients with CCHF who were hospitalized in Boo-Ali hospital in Zahedan between Oct 2009 to Feb 2012. Liver function tests including aminotransferase enzymes and prothrombin time and mortality rate were evaluated. Results: Among 53 patients with CCHF, hepatitis was seen in 19 patients (45%. Nine patients died (21%. All dead patients had a serum aminotransaminase level ≥10 times the upper normal limit. Conclusion: Our study showed that hepatitis is prevalent in CCHF patients and a serum aminotransaminase level ≥5 times the upper normal limit (UNL is a risk factor for severe disease and high mortality.

  2. Ocular pentastomiasis in the Democratic Republic of the Congo.

    Directory of Open Access Journals (Sweden)

    Mihály Sulyok

    2014-07-01

    Full Text Available Ocular pentastomiasis is a rare infection caused by the larval stage of pentastomids, an unusual group of crustacean-related parasites. Zoonotic pentastomids have a distinct geographical distribution and utilize reptiles or canids as final hosts. Recently, an increasing number of human abdominal infections have been reported in Africa, where pentastomiasis is an emerging, though severely neglected, tropical disease. Here we describe four ocular infections caused by pentastomids from the Democratic Republic of the Congo. Two cases underwent surgery and an Armillifer grandis infection was detected by morphological and molecular approaches. Thus far, 15 other cases of ocular pentastomiasis have been reported worldwide. Twelve cases were caused by Armillifer sp., recorded almost exclusively in Africa, where such infections occur as a consequence of hunting and consuming snakes, their final hosts. Seven further cases were caused by Linguatula serrata, a cosmopolitan pentastomid whose final hosts are usually canids. Intraocular infections caused permanent visual damage in 69% and a total loss of vision in 31% of reported cases. In contrast, ocular adnexal cases had a benign clinical course. Further research is required to estimate the burden, therapeutic options and pathogenesis of this neglected disease.

  3. Diet and kwashiorkor: a prospective study from rural DR Congo

    Directory of Open Access Journals (Sweden)

    Hallgeir Kismul

    2014-04-01

    Full Text Available The etiology of kwashiorkor remains enigmatic and longitudinal studies examining potential causes of kwashiorkor are scarce. Using historical, longitudinal study data from the rural area of Bwamanda, Democratic Republic of Congo, we investigated the potential causal association between diet and the development of kwashiorkor in 5 657 preschool children followed 3-monthly during 15 months. We compared dietary risk factors for kwashiorkor with those of marasmus. Kwashiorkor was diagnosed as pitting oedema of the ankles; marasmus as abnormal visibility of skeletal structures and palpable wasting of the gluteus muscle. A 24-h recall was administered 3-monthly to record the consumption of the 41 locally most frequent food items. We specified Hanley–Miettinen smooth-in-time risk models containing potential causal factors, including food items, special meals prepared for the child, breastfeeding, disease status, nutritional status, birth rank, age, season and number of meals. Bayesian Information Criteria identified the most plausible causal model of why some children developed kwashiorkor. In a descriptive analysis of the diet at the last dietary assessment prior to development of kwashiorkor, the diet of children who developed kwashiorkor was characterized by low consumption of sweet potatoes, papaya and “other vegetables” [0.0% , 2.3% (95% CI [0.4, 12.1] and 2.3% (95% CI [0.4, 12.1

  4. Assessing Monkeypox Virus Prevalence in Small Mammals at the Human–Animal Interface in the Democratic Republic of the Congo

    Directory of Open Access Journals (Sweden)

    Jeffrey B. Doty

    2017-10-01

    Full Text Available During 2012, 2013 and 2015, we collected small mammals within 25 km of the town of Boende in Tshuapa Province, the Democratic Republic of the Congo. The prevalence of monkeypox virus (MPXV in this area is unknown; however, cases of human infection were previously confirmed near these collection sites. Samples were collected from 353 mammals (rodents, shrews, pangolins, elephant shrews, a potamogale, and a hyrax. Some rodents and shrews were captured from houses where human monkeypox cases have recently been identified, but most were trapped in forests and agricultural areas near villages. Real-time PCR and ELISA were used to assess evidence of MPXV infection and other Orthopoxvirus (OPXV infections in these small mammals. Seven (2.0% of these animal samples were found to be anti-orthopoxvirus immunoglobulin G (IgG antibody positive (six rodents: two Funisciurus spp.; one Graphiurus lorraineus; one Cricetomys emini; one Heliosciurus sp.; one Oenomys hypoxanthus, and one elephant shrew Petrodromus tetradactylus; no individuals were found positive in PCR-based assays. These results suggest that a variety of animals can be infected with OPXVs, and that epidemiology studies and educational campaigns should focus on animals that people are regularly contacting, including larger rodents used as protein sources.

  5. Assessing Monkeypox Virus Prevalence in Small Mammals at the Human-Animal Interface in the Democratic Republic of the Congo.

    Science.gov (United States)

    Doty, Jeffrey B; Malekani, Jean M; Kalemba, Lem's N; Stanley, William T; Monroe, Benjamin P; Nakazawa, Yoshinori U; Mauldin, Matthew R; Bakambana, Trésor L; Liyandja Dja Liyandja, Tobit; Braden, Zachary H; Wallace, Ryan M; Malekani, Divin V; McCollum, Andrea M; Gallardo-Romero, Nadia; Kondas, Ashley; Peterson, A Townsend; Osorio, Jorge E; Rocke, Tonie E; Karem, Kevin L; Emerson, Ginny L; Carroll, Darin S

    2017-10-03

    During 2012, 2013 and 2015, we collected small mammals within 25 km of the town of Boende in Tshuapa Province, the Democratic Republic of the Congo. The prevalence of monkeypox virus (MPXV) in this area is unknown; however, cases of human infection were previously confirmed near these collection sites. Samples were collected from 353 mammals (rodents, shrews, pangolins, elephant shrews, a potamogale, and a hyrax). Some rodents and shrews were captured from houses where human monkeypox cases have recently been identified, but most were trapped in forests and agricultural areas near villages. Real-time PCR and ELISA were used to assess evidence of MPXV infection and other Orthopoxvirus (OPXV) infections in these small mammals. Seven (2.0%) of these animal samples were found to be anti-orthopoxvirus immunoglobulin G (IgG) antibody positive (six rodents: two Funisciurus spp.; one Graphiurus lorraineus ; one Cricetomys emini ; one Heliosciurus sp.; one Oenomys hypoxanthus , and one elephant shrew Petrodromus tetradactylus ); no individuals were found positive in PCR-based assays. These results suggest that a variety of animals can be infected with OPXVs, and that epidemiology studies and educational campaigns should focus on animals that people are regularly contacting, including larger rodents used as protein sources.

  6. Colorado River basin sensitivity to disturbance impacts

    Science.gov (United States)

    Bennett, K. E.; Urrego-Blanco, J. R.; Jonko, A. K.; Vano, J. A.; Newman, A. J.; Bohn, T. J.; Middleton, R. S.

    2017-12-01

    The Colorado River basin is an important river for the food-energy-water nexus in the United States and is projected to change under future scenarios of increased CO2emissions and warming. Streamflow estimates to consider climate impacts occurring as a result of this warming are often provided using modeling tools which rely on uncertain inputs—to fully understand impacts on streamflow sensitivity analysis can help determine how models respond under changing disturbances such as climate and vegetation. In this study, we conduct a global sensitivity analysis with a space-filling Latin Hypercube sampling of the model parameter space and statistical emulation of the Variable Infiltration Capacity (VIC) hydrologic model to relate changes in runoff, evapotranspiration, snow water equivalent and soil moisture to model parameters in VIC. Additionally, we examine sensitivities of basin-wide model simulations using an approach that incorporates changes in temperature, precipitation and vegetation to consider impact responses for snow-dominated headwater catchments, low elevation arid basins, and for the upper and lower river basins. We find that for the Colorado River basin, snow-dominated regions are more sensitive to uncertainties. New parameter sensitivities identified include runoff/evapotranspiration sensitivity to albedo, while changes in snow water equivalent are sensitive to canopy fraction and Leaf Area Index (LAI). Basin-wide streamflow sensitivities to precipitation, temperature and vegetation are variable seasonally and also between sub-basins; with the largest sensitivities for smaller, snow-driven headwater systems where forests are dense. For a major headwater basin, a 1ºC of warming equaled a 30% loss of forest cover, while a 10% precipitation loss equaled a 90% forest cover decline. Scenarios utilizing multiple disturbances led to unexpected results where changes could either magnify or diminish extremes, such as low and peak flows and streamflow timing

  7. The Ritual "Play of the Congos" of North-Central Panama: Its Sociolinguistic Implications. Sociolinguistic Working Paper Number 85.

    Science.gov (United States)

    Joly, Luz Graciela

    An excerpt from the "Play of the Congos," given in Congo, Spanish, and English, exemplifies the sociolinguistic features of the combined play and ritual language used by the Afro-Hispanic population in the Caribbean region of the Costa Abajo in north-central Panama. The sociolinguistic norms are an important part of the "regulation…

  8. Four new species of deep water agglutinated foraminifera from the Oligocene-Miocene of the Congo Fan (offshore Angola)

    OpenAIRE

    Kender, S.; Kaminski, M. A.; Jones, R. W.

    2006-01-01

    Four new species of deep-water agglutinated benthic foraminifera are described from the Oligocene and Miocene of the Congo Fan, offshore Angola. Scherochorella congoensis n.sp., Paratrochamminoides goroyskiformis n.sp., Haplophragmoides nauticus n.sp. and Portatrochammina profunda n.sp. all occur in deep-sea turbiditic shales and sands from the distal section of the Congo Fan.

  9. NASA LCLUC Program: An Integrated Forest Monitoring System for Central Africa

    Science.gov (United States)

    Laporte, Nadine; LeMoigne, Jacqueline; Elkan, Paul; Desmet, Olivier; Paget, Dominique; Pumptre, Andrew; Gouala, Patrice; Honzack, Miro; Maisels, Fiona

    2004-01-01

    Central Africa has the second largest unfragmented block of tropical rain forest in the world; it is also one of the largest carbon and biodiversity reservoirs. With nearly one-third of the forest currently allocated for logging, the region is poised to undergo extensive land-use change. Through the mapping of the forests, our Integrated Forest Monitoring System for Central Africa (INFORMS) project aims to monitor habitat alteration, support biodiversity conservation, and promote better land-use planning and forest management. Designed as an interdisciplinary project, its goal is to integrate data acquired from satellites with field observations from forest inventories, wildlife surveys, and socio-economic studies to map and monitor forest resources. This project also emphasizes on collaboration and coordination with international, regional, national, and local partners-including non-profit, governmental, and commercial sectors. This project has been focused on developing remote sensing products for the needs of forest conservation and management, insuring that research findings are incorporated in forest management plans at the national level. The societal impact of INFORMS can be also appreciated through the development of a regional remote sensing network in central Africa. With a regional office in Kinshasa, (www.OSFAC.org), the contribution to the development of forest management plans for 1.5 million hectares of forests in northern Republic of Congo (www.tt-timber.com), and the monitoring of park encroachments in the Albertine region (Uganda and DRC) (www.albertinerift.org).

  10. Intensive measurements of gas, water, and energy exchange between vegetation and troposphere during the MONTES Campaign in a vegetation gradient from short semi-desertic shrublands to tall wet temperate forests in the NW Mediterranean basin

    Science.gov (United States)

    MONTES (“Woodlands”) was a multidisciplinary international field campaign aimed at measuring energy, water and especially gas exchange between vegetation and atmosphere in a gradient from short semi-desertic shrublands to tall wet temperate forests in NE Spain in the North Wester...

  11. Intensive measurements of gas, water, and energy exchange between vegetation and troposhere during the MONTES campaign in a vegetation gradient from short semi-desertic shrublands to tall wet temperate forests in the NW Mediterranean Basin

    NARCIS (Netherlands)

    Penuelas, J.; Guenther, A.; Rapparini, F.; Llusia, J.; Vilà-Guerau De Arellano, J.

    2013-01-01

    MONTES (“Woodlands”) was a multidisciplinary international field campaign aimed at measuring energy, water and especially gas exchange between vegetation and atmosphere in a gradient from short semi-desertic shrublands to tall wet temperate forests in NE Spain in the North Western Mediterranean

  12. Mapping and characterizing the vegetation types of the Democratic Republic of Congo using SPOT VEGETATION time series

    Science.gov (United States)

    Vancutsem, C.; Pekel, J.-F.; Evrard, C.; Malaisse, F.; Defourny, P.

    2009-02-01

    The need for quantitative and accurate information to characterize the state and evolution of vegetation types at a national scale is widely recognized. This type of information is crucial for the Democratic Republic of Congo, which contains the majority of the tropical forest cover of Central Africa and a large diversity of habitats. In spite of recent progress in earth observation capabilities, vegetation mapping and seasonality analysis in equatorial areas still represent an outstanding challenge owing to high cloud coverage and the extent and limited accessibility of the territory. On one hand, the use of coarse-resolution optical data is constrained by performance in the presence of cloud screening and by noise arising from the compositing process, which limits the spatial consistency of the composite and the temporal resolution. On the other hand, the use of high-resolution data suffers from heterogeneity of acquisition dates, images and interpretation from one scene to another. The objective of the present study was to propose and demonstrate a semi-automatic processing method for vegetation mapping and seasonality characterization based on temporal and spectral information from SPOT VEGETATION time series. A land cover map with 18 vegetation classes was produced using the proposed method that was fed by ecological knowledge gathered from botanists and reference documents. The floristic composition and physiognomy of each vegetation type are described using the Land Cover Classification System developed by the FAO. Moreover, the seasonality of each class is characterized on a monthly basis and the variation in different vegetation indicators is discussed from a phenological point of view. This mapping exercise delivers the first area estimates of seven different forest types, five different savannas characterized by specific seasonality behavior and two aquatic vegetation types. Finally, the result is compared to two recent land cover maps derived from

  13. Time still to restore the polluted Piracicaba river basin

    International Nuclear Information System (INIS)

    Favaro, P.C.; De Nadai Fernandes, E.A.; Ferraz, E.S.B.; Falotico, M.H.B.

    2004-01-01

    Over the last decades the acceleration of the industrialization and urbanization processes together with the intensive agricultural practices have resulted in an impact on the Piracicaba river basin, state of Sao Paulo, Brazil. The source rivers drain from an area of low population density, absence of heavy industries, non-significant agriculture, native forest and reforestation, the opposite is found in the middle part of the basin. Samples of riverbed sediments were collected along the basin for chemical analysis. Results showed that the source rivers still preserve their natural characteristics, while the Atibaia river in the middle part shows signs of pollution from the agricultural activity, industrial effluents and urban sewage. (author)

  14. Optical properties of amyloid stained by Congo red: history and mechanisms.

    Science.gov (United States)

    Howie, Alexander J; Brewer, Douglas B

    2009-04-01

    Amyloid stained by Congo red has striking optical properties that generally have been poorly described and inadequately explained, although they can be understood from principles of physical optics. Molecules of Congo red are orientated on amyloid fibrils, and so the dye becomes dichroic and birefringent. The birefringence varies with wavelength in accordance with a fundamental property of all light-transmitting materials called anomalous dispersion of the refractive index around an absorption peak. The combination of this and absorption of light, with modification by any additional birefringence in the optical system, explains the various colours that can be seen in Congo red-stained amyloid between crossed polariser and analyser, and also when the polariser and analyser are progressively uncrossed. These are called anomalous colours.

  15. Deforestation trends of tropical dry forests in central Brazil

    Science.gov (United States)

    Bianchi, Carlos A.; Haig, Susan M.

    2013-01-01

    Tropical dry forests are the most threatened forest type in the world yet a paucity of research about them stymies development of appropriate conservation actions. The Paranã River Basin has the most significant dry forest formations in the Cerrado biome of central Brazil and is threatened by intense land conversion to pastures and agriculture. We examined changes in Paranã River Basin deforestation rates and fragmentation across three time intervals that covered 31 yr using Landsat imagery. Our results indicated a 66.3 percent decrease in forest extent between 1977 and 2008, with an annual rate of forest cover change of 3.5 percent. Landscape metrics further indicated severe forest loss and fragmentation, resulting in an increase in the number of fragments and reduction in patch sizes. Forest fragments in flatlands have virtually disappeared and the only significant forest remnants are mostly found over limestone outcrops in the eastern part of the basin. If current patterns persist, we project that these forests will likely disappear within 25 yr. These patterns may be reversed with creation of protected areas and involvement of local people to preserve small fragments that can be managed for restoration.

  16. Great Basin Research and Management Project: Restoring and maintaining riparian ecosystem integrity

    Science.gov (United States)

    Jeanne C. Chambers

    2000-01-01

    The Great Basin Research and Management Project was initiated in 1994 by the USDA Forest Service, Rocky Mountain Research Station’s Ecology, Paleoecology, and Restoration of Great Basin Watersheds Project to address the problems of stream incision and riparian ecosystem degradation in central Nevada. It is a highly interdisciplinary project that is being conducted in...

  17. Native plant development and restoration program for the Great Basin, USA

    Science.gov (United States)

    N. L. Shaw; M. Pellant; P. Olweli; S. L. Jensen; E. D. McArthur

    2008-01-01

    The Great Basin Native Plant Selection and Increase Project, organized by the USDA Bureau of Land Management, Great Basin Restoration Initiative and the USDA Forest Service, Rocky Mountain Research Station in 2000 as a multi-agency collaborative program (http://www.fs.fed.us/rm/boise/research/shrub/greatbasin.shtml), has the objective of improving the availability of...

  18. Anatomie de la Corruption en République Démocratique du Congo

    OpenAIRE

    Kodila Tedika, Oasis

    2013-01-01

    This article analysis a nature of corruption in Democratic Republic of Congo. It shows, with arguments, on the one hand the deserved reputation for a highly corrupt country, that one reads regularly in different collations on corruption and says to the complexity and depth of the corruption. The basis of the systemic side of corruption in this country. Cet article a pour objectif de décortiquer la nature de la corruption en République démocratique du Congo. Il démontre, avec arguments, d’une ...

  19. Effective Removal of Congo Red by Triarrhena Biochar Loading with TiO2 Nanoparticles

    Directory of Open Access Journals (Sweden)

    Peng Yu

    2018-01-01

    Full Text Available A composite of pyrolytic Triarrhena biochar loading with TiO2 nanoparticles has been synthesized by the sol-gel method. The composite shows a well-developed hollow mesoporous and macropore structure as characterized by XRD, BET, and SEM. When used as an absorbent to remove Congo red from aqueous solution, it was found that as-prepared composite performed better absorption capacity than single biochar or TiO2. The results suggest that biochar loading with TiO2 could be promisingly implemented as an environmentally friendly and inexpensive adsorbent for Congo red removal from wastewater.

  20. A crimean - congo hemorrhagic fever outbreak in northern balochistan

    International Nuclear Information System (INIS)

    Nadeem, M.; Ali, N.

    2007-01-01

    To describe the clinical characteristics, epidemiology, predictors of fatal outcome (PFO), and management effects of Crimean-Congo haemorrhagic fever (CCHF) patients during an outbreak in Northern Balochistan. Patients presenting with a fever of less than 2 weeks duration and bleeding manifestations were included. Clinical history was recorded and patients were placed on oral ribavirin, and hematological support. Diagnosis was established by PCR for CCHF or detection of CCHF specific IgM and IgG. Eighty-four patients were received, 34 (40.5%) were suspected of suffering from classical CCHF. All 34 (100%) patients presented with a history of fever and bleeding (epistaxis, gum bleeding, melena or haematuria). Mean platelet count was 30 x 109/L and mean ALT (alanine transferase) was 288 U/L. Among fatal cases, the mean platelet count was 18.4 x 10 9/L and ALT was 781 units/L. PCR for CCHF viral RNA performed on 10 patients was positive in 3 (30%) patients. CCHF specific IgM and IgG was positive in 17.6% (6/34). Four patients were brought in moribund condition and expired before treatment could be started, 4 patients expired during treatment and 76.5% (26/34) were cured. The overall mortality was 23.5% (8/34). Main predictors of fatal outcome were ALT z 150 units/L, activated partial thromboplastin time(aPT) z 60 seconds, prothrombin time (PT) z 34 seconds, aspartate transferase (AST) z 200 units/L, platelets o 20 x 109/L, and fibrinogen o 110 mg/dL. In this series of CCHF occurring in Northern parts of Balochistan, gastrointestinal tract bleeding was the worst prognostic factor associated with fatal outcome. Providing education to healthcare workers and at risk populations, hematological support, antiviral drugs, and barrier nursing may help reduce mortality. (author)

  1. Vectors of Crimean Congo Hemorrhagic Fever Virus in Iran

    Directory of Open Access Journals (Sweden)

    Zakkyeh Telmadarraiy

    2015-10-01

    Full Text Available Background: Ticks are important vectors and reservoirs of Crimean Congo Hemorrhagic Fever (CCHF virus. Human beings may be infected whenever the normal life cycle of the infected ticks on non- human vertebrate hosts is interrupted by the undesirable presence of humans in the cycle. A total of 26 species of Argasid and Ixodid ticks have been recorded in Iran; including nine Hyalomma, two Rhipicephalus, two Dermacentor, five Haemaphysalis, two Boophilus, one Ixodes and two Argas as well as three Ornithodoros species as blood sucking ectoparasites of livestock and poultries. The present paper reviews tick vectors of CCHF virus in Iran, focusing on the role of ticks in different provinces of Iran using reverse transcription polymerase chain reaction (RT-PCR assay.Methods: During ten years study, 1054 tick specimens; including two species of Argasidae and 17 species of Ixodidae were examined for their infection to CCHF virus genome. The output of all studies as well as related publications were discussed in the current paper.Results: The results show that Rhipicephalus sanguineus, Hyalomma marginatum, H. anatolicum, H. asiaticum and H. dromedarii were known as the most frequent species which were positive for CCHF virus.Conclusion: The status of ticks which were positive for CCHF virus revealed that unlike the most common idea that Hyalomma species are the most important vectors of CCHF virus, other ticks including Rhipicephalus,Haemaphysalis and Dermacentor can be reservoir of this virus; thus, considering geographical distribution, type of host and environmental conditions, different tick control measurements should be carried out in areas with high incidence of CCHF disease.

  2. Vectors of Crimean Congo Hemorrhagic Fever Virus in Iran

    Science.gov (United States)

    Telmadarraiy, Zakkyeh; Chinikar, Sadegh; Vatandoost, Hassan; Faghihi, Faezeh; Hosseini-Chegeni, Asadollah

    2015-01-01

    Background: Ticks are important vectors and reservoirs of Crimean Congo Hemorrhagic Fever (CCHF) virus. Human beings may be infected whenever the normal life cycle of the infected ticks on non-human vertebrate hosts is interrupted by the undesirable presence of humans in the cycle. A total of 26 species of Argasid and Ixodid ticks have been recorded in Iran; including nine Hyalomma, two Rhipicephalus, two Dermacentor, five Haemaphysalis, two Boophilus, one Ixodes and two Argas as well as three Ornithodoros species as blood sucking ectoparasites of livestock and poultries. The present paper reviews tick vectors of CCHF virus in Iran, focusing on the role of ticks in different provinces of Iran using reverse transcription polymerase chain reaction (RT-PCR) assay. Methods: During ten years study, 1054 tick specimens; including two species of Argasidae and 17 species of Ixodidae were examined for their infection to CCHF virus genome. The output of all studies as well as related publications were discussed in the current paper. Results: The results show that Rhipicephalus sanguineus, Hyalomma marginatum, H. anatolicum, H. asiaticum and H. dromedarii were known as the most frequent species which were positive for CCHF virus. Conclusion: The status of ticks which were positive for CCHF virus revealed that unlike the most common idea that Hyalomma species are the most important vectors of CCHF virus, other ticks including Rhipicephalus, Haemaphysalis and Dermacentor can be reservoir of this virus; thus, considering geographical distribution, type of host and environmental conditions, different tick control measurements should be carried out in areas with high incidence of CCHF disease. PMID:26623426

  3. Texas' forests, 2008

    Science.gov (United States)

    James W. Bentley; Consuelo Brandeis; Jason A. Cooper; Christopher M. Oswalt; Sonja N. Oswalt; KaDonna Randolph

    2014-01-01

    This bulletin describes forest resources of the State of Texas at the time of the 2008 forest inventory. This bulletin addresses forest area, volume, growth, removals, mortality, forest health, timber product output, and the economy of the forest sector.

  4. Forest resources of the Lincoln National Forest

    Science.gov (United States)

    John D. Shaw

    2006-01-01

    The Interior West Forest Inventory and Analysis (IWFIA) program of the USDA Forest Service, Rocky Mountain Research Station, as part of its national Forest Inventory and Analysis (FIA) duties, conducted forest resource inventories of the Southwestern Region (Region 3) National Forests. This report presents highlights of the Lincoln National Forest 1997 inventory...

  5. Research and management of soil, plant, animal, and human resources in the Middle Rio Grande Basin

    Science.gov (United States)

    Deborah M. Finch

    1996-01-01

    The Rocky Mountain Forest and Range Experiment Station initiated a research program in 1994 called. "Ecology, diversity, and sustainability of soil, plant, animal, and human resources of the Rio Grande Basin". This program is funded by an Ecosystem Management grant from Forest Service Research. Its mission focuses on the development and application of new...

  6. Survival and movement of the Congo forest mouse (Deomys ferrugineus): a comparison of primary rainforest and fallow land in Kisangani, Democratic Republic of the Congo

    DEFF Research Database (Denmark)

    Kennis, John; Laurent, Crespin; Amundala, Nicaise Drazo

    2012-01-01

    of habitat on rodent life history both in primary rainforest and fallow land. Survival analyses taking into account trap-happiness effects were conducted using the program MARK. Abundance of D. ferrugineus was generally low within all our study grids, but it was lowest in fallow land compared to primary...... rainforest. Numbers of reproductively active females captured were not different between habitats but were larger during the rainy seasons. Daily movements of females, but not of males, were smaller in fallow land. Capture-mark-recapture analyses showed recapture probabilities to vary highly between grids...

  7. The presence of Praomys, Lophuromys, and Deomys species (Muridae, Mammalia) in the forest blocks separated by the Congo River and its tributaries (Kisangani region, Democratic Republic of Congo)

    DEFF Research Database (Denmark)

    Katuala, Pionus G B; Kennis, Jan; Nicolas, Violaine

    2008-01-01

    Praomys (four species), Lophuromys (four) and Deomys (one) are among the most common Muridae in the Kisangani region. To establish whether or not rivers constitute dispersal barriers for these rodents, we investigated the presence of these genera and their species in eight localities that are eit......Praomys (four species), Lophuromys (four) and Deomys (one) are among the most common Muridae in the Kisangani region. To establish whether or not rivers constitute dispersal barriers for these rodents, we investigated the presence of these genera and their species in eight localities...

  8. Evaluation of sugar-cane bagasse as bioadsorbent in the textile wastewater treatment contaminated with carcinogenic congo red dye

    Directory of Open Access Journals (Sweden)

    Aline Sartório Raymundo

    2010-08-01

    Full Text Available A methodology involving sugar cane bagasse bioadsorbent was developed in order to remove the carcinogenic congo red dye from aqueous medium. The results showed high efficiency with retention of 64 ± 6% in synthetic congo red solution and 94 ± 5% in effluent enriched with congo red, at 10.0 g of the bioadsorbent. The adsorption system provided a maximum adsorption capacity of 4.43 mg/g. Tests showed independence adsorption properties, when compared with the column flow rates. The treatment units could be operated with flexibility. From the results, it was possible to conclude that sugar cane bagasse could be an adequate bioadsorbent.Neste trabalho foi desenvolvida uma metodologia de remoção do corante carcinogênico congo red de sistemas aquosos. Os resultados mostraram uma elevada eficiência de remoção sendo de 64 ± 6% para soluções sintéticas de vermelho congo, e 94 ± 5% para efluente industrial enriquecido com vermelho congo utilizando 10 g de bioadsorvente. A capacidade máxima adsotiva encontrada foi de 4,43 mg/g. Os testes de percolação revelaram independência das porcentagens adsortivas em relação às vazões das colunas. Estes resultados indicam viabilidade de uso do bagaço de cana-de-açucar no tratamento de efluentes contendo o congo red.

  9. Invertebrates of the Columbia River basin assessment area.

    Science.gov (United States)

    Christine G. Niwa; Roger E. Sandquist; Rod Crawford; et al.

    2001-01-01

    A general background on functional groups of invertebrates in the Columbia River basin and how they affect sustainability and productivity of their ecological communities is presented. The functional groups include detritivores, predators, pollinators, and grassland and forest herbivores. Invertebrate biodiversity and species of conservation interest are discussed....

  10. Biotic diversity interfaces with urbanization in the Lake Tahoe basin

    Science.gov (United States)

    Patricia N. Manley; Dennis D. Murphy; Lori A. Campbell; Kirsten E. Heckmann; Susan Merideth; Sean A. Parks; Monte P. Sanford; Matthew D. Schlesinger

    2006-01-01

    In the Lake Tahoe Basin, the retention of native ecosystems within urban areas may greatly enhance the landscape’s ability to maintain biotic diversity. Our study of plant, invertebrate and vertebrate species showed that many native species were present in remnant forest stands in developed areas; however, their richness and abundance declined in association with...

  11. Synergy between land use and climate change increases future risk in Amazon forests

    OpenAIRE

    Le Page, Yannick; Morton, Douglas; Hartin, Corinne; Bond-Lamberty, Ben; Pereira, José Miguel Cardoso; Hurtt, George; Asrar, Ghassem

    2017-01-01

    Tropical forests have been a permanent feature of the Amazon basin for at least 55 million years, yet climate change and land use threaten the forest’s future over the next century. Understory forest fires, which are common under the current climate in frontier forests, may accelerate Amazon forest losses from climatedriven dieback and deforestation. Far from land use frontiers, scarce fire ignitions and high moisture levels preclude significant burning, yet projected climate and ...

  12. Commitment to a Lady’s First WIN : Banking Innovation in the Democratic Republic of Congo

    OpenAIRE

    Vivian Awiti Owuor

    2011-01-01

    Doing business is challenging in the Democratic Republic of Congo and presents opportunities for innovative approaches to banking, especially for micro, small, and medium enterprises (MSMEs) - and particularly for women entrepreneurs. But it is getting easier, thanks to innovating banking. This SmartLesson reviews some of the early lessons learned from the ongoing implementation of a Women...

  13. Congo, de missie en de literatuur: Over David van Reybrouck, J. G. ...

    African Journals Online (AJOL)

    However, the travel books written by Lieve Joris and Bart Castelein and the play Missie (Mission) written by David van Reybrouck (2007) sketched a positive and nostalgic image of the missionary. Keywords: Dutch (post)colonial literature, Congo, missionaries, colonialism. Tydskrif vir Letterkunde Vol. 46 (1) 2009: pp. 123- ...

  14. Les effets du changement climatique dans le bassin du Congo : la ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    22 avr. 2016 ... Dans le bassin du fleuve Congo, plus de 80 % des habitants vivent exclusivement de l'agriculture, de la pêche, de l'élevage et de la cueillette, qui sont des activités largement tributaires du climat.

  15. Heath sector network governance and State-building in South Kivu, Democratic Republic of Congo

    NARCIS (Netherlands)

    Bwimana, Aembe

    2017-01-01

    Longstanding patterns of interaction exist between state and non-state actors seeking to improve public health in Democratic Republic of Congo (DRC). DRC is a weak state, and, in many cases, private actors have stepped in to fill the void created by the lack of state health care provision. However,

  16. A model to predict when a cholera outbreak might hit the Congo

    Science.gov (United States)

    Schultz, Colin

    2014-09-01

    In 2011, as many as 600,000 people in 58 countries contracted cholera, with thousands succumbing to the disease. In most countries, cholera is rare. In others, like the Democratic Republic of the Congo, cholera is an endemic threat, always lurking in the background waiting for the right set of conditions to spark an outbreak.

  17. A case report of crimean congo hemorrhagic Fever in ostriches in iran

    DEFF Research Database (Denmark)

    Mostafavi, Ehsan; Chinikar, Sadegh; Moradi, Maryam

    2013-01-01

    Crimean Congo hemorrhagic fever (CCHF) is a viral zoonosis, which is usually transmitted via tick bites or close contact with infected blood or tissue. This disease can cause a case fatality rate of up to 25%-30% in humans. CCHF Infection in birds is less documented. An ostrich can reproduce...

  18. Les écoles au Congo belge en 1924. Le rapport De Jonghe ...

    African Journals Online (AJOL)

    enseignement au Congo, exprimé dans le projet de 1922, De Jonghe a entrepris un voyage de reconnaissance en 1924. Une nouvelle version du Projet paraissait en 1925 et la version définitive est approuvée en 1928 et publiée en 1929.

  19. Enhanced adsorptive degradation of Congo red in aqueous solutions using polyaniline/Fe0 composite nanofibers

    CSIR Research Space (South Africa)

    Bhaumik, M

    2015-01-01

    Full Text Available In this study, a simple approach was described for the fabrication of composite nanofibers (CNFs) of polyaniline/Fe0 (PANI/Fe0) using a template-free method for the reductive degradation and removal of Congo red (CR) from aqueous solutions. The PANI...

  20. Phytochemical analysis and biological evaluation of selected African propolis samples from Cameroon and Congo

    NARCIS (Netherlands)

    Papachroni, D.; Graikou, K.; Kosalec, I.; Damianakos, H.; Ingram, V.J.; Chinou, I.

    2015-01-01

    The objective of this study was the chemical analysis of four selected samples of African propolis (Congo and Cameroon) and their biological evaluation. Twenty-one secondary metabolites belonging to four different chemical groups were isolated from the 70% ethanolic extracts of propolis and their

  1. An outbreak of West Nile fever among migrants in Kisangani, Democratic Republic of Congo.

    NARCIS (Netherlands)

    Y.A. Nur; J. Groen (Jan); H. Heuvelmans; W. Tuynman; C. Copra (Cederick); A.D.M.E. Osterhaus (Albert)

    1999-01-01

    textabstractIn February 1998, an outbreak of acute febrile illness was reported from the Kapalata military camp in Kisangani, the Democratic Republic of Congo. The illness was characterized by an acute onset of fever associated with severe headache, arthralgia, backache, neurologic signs, abdominal

  2. An outbreak of West Nile fever among migrants in Kisangani, Democratic Republic of Congo

    NARCIS (Netherlands)

    Y.A. Nur; J. Groen (Jan); H. Heuvelmans; W. Tuynman; C. Copra (Cederick); A.D.M.E. Osterhaus (Albert)

    1999-01-01

    textabstractIn February 1998, an outbreak of acute febrile illness was reported from the Kapalata military camp in Kisangani, the Democratic Republic of Congo. The illness was characterized by an acute onset of fever associated with severe headache, arthralgia, backache, neurologic

  3. Leopard-men of the Congo in literature and popular imagination ...

    African Journals Online (AJOL)

    The Anyoto leopard-men, a society from eastern Congo, operated between approximately 1890 and 1935. Until now the history of the leopard-men has inspired representations of Central Africa as a barbaric and disorderly place, and the idea that a secret association of men attacked innocent people and ate their limbs ...

  4. Gestion des espaces publics au Congo-Brazzaville: le cas des ...

    African Journals Online (AJOL)

    The issue of public spaces in Congo-Brazzaville is at the heart of municipal political debates. At the level of public transport, the management of public spaces remains above all in the hands of the mayor's office and municipal councillors. The agreements between these authorities and the contractors running public ...

  5. Managing (Fiscally) Resource Windfalls : Exploring Policy Options for the Democratic Republic of Congo

    OpenAIRE

    Pinto-Moreira, Emmanuel

    2016-01-01

    How should resource-dependent countries respond (fiscally) to resource price volatility? This note studies what determines revenue allocation between a "spend today" strategy and a "save now-spend tomorrow" approach in the context of the Democratic Republic of Congo. It uses a three-sector model in which public infrastructure investment has tangible benefits for private production and inve...

  6. "New Education" for the Congo? The Indigenist Approach, New Education and Prescriptive Pedagogy

    Science.gov (United States)

    Depaepe, Marc; Simon, Frank; Vinck, Honoré

    2015-01-01

    This article responds to a question put forward approximately a decade ago by the history of education research group at the Katholieke Universiteit Leuven: Did the child-centred ideas of New Education, as promoted by Ovide Decroly, influence the education policy in the former Belgian colony of Congo? Naturally, ideas were circulating that could…

  7. Medical Orders: Catholic and Protestant Missionary Medicine in the Belgian Congo 1880-1940

    Directory of Open Access Journals (Sweden)

    Sokhieng Au

    2017-03-01

    Full Text Available The history of religious missions and the provisioning of western medical care in the region that was known as the Congo Free State and later the Belgian Congo reveals the complicated dynamics between competing religious missions vis à vis the Belgian colonial state. This essay highlights divisions between identities and purposes of different religious groups in medical care provisioning, focusing on the divide between the Catholic and Protestant churches. Because most Protestant missions in the Congo were American or British, the medical care provided by the Protestant church was outside of, and sometimes at odds with, the Belgian colonial state until the 1920s. In contrast, the Catholic Church served in an auxiliary role in the colonial state’s medical infrastructure. This was not an ideal situation, leading Catholic leaders to attempt to rework the church’s role in medical provisioning. Ultimately, mission, medicine, and empire were not always comfortable bedfellows. Medische Orders: katholieke en protestantse missiegeneeskunde in de Belgische Congo 1880-1940De geschiedenis van de religieuze missies en het voorzien in westerse medische gezondheidszorg in de Congo Vrijstaat – later de Belgische Congo – onthult de ingewikkelde dynamiek tussen de concurrerende religieuze missies vis à vis de Belgische koloniale staat. Dit artikel belicht verschillende religieuze groepen die medische zorg verleenden in deze regio en hun verdeeldheid inzake identiteiten en doelen. Hierbij wordt vooral gefocust op de tweedracht tussen de katholieke en protestantse kerk. Omdat de meeste protestantse missies die in de Congo gevestigd waren uit Amerika of Engeland kwamen, werd de medische zorg die zij verstrekten vaak buiten de Belgische koloniale staat om geleverd en leefden staat en protestantse kerk tot in de jaren 1920 soms op gespannen voet met elkaar. Dit staat in sterk contrast tot de katholieke kerk die wat betreft medische infrastructuur juist een

  8. Efeito do gradiente altitudinal/latitudinal sobre espécies de aves florestais da família Furnariidae na Bacia do Rio Tibagi, Paraná, Brasil Effect of altitudinal/latitudinal gradient about forest ovenbirds species (Aves: Furnariidae in the Tibagi river basin, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Fernando de L. Fávaro

    2006-03-01

    Full Text Available Variações na riqueza e abundância de Furnariidae florestais foram analisadas ao longo do gradiente altitudinal/latitudinal da bacia do rio Tibagi (BRT, Paraná, Brasil. A Floresta Ombrófila Mista (1060 m a.n.m. é a formação dominante no sul da BRT, enquanto que a Floresta Estacional Semidecidual (298 m a.n.m., ocorre no norte. O número total de espécies obtidas na BRT foi 14. A riqueza e a abundância de Furnariidae foram maiores no sul (12 espécies, IPA = 2,01 do que no norte (cinco espécies, IPA = 0,45 da BRT. As similaridades também foram altas entre o sul e o centro da BRT. A estrutura da comunidade de Furnariidae também apresentou correlação positiva entre o sul e o centro da BRT (coeficiente de correlação por postos de Spearman; r s = 0,96, r s = 0,89, r s = 1,00. As relações evolutivas de alguns representantes de Furnariidae com o sul da América do Sul e com os Andes podem explicar a maior presença desta família no sul da BRT. Um outro aspecto que também pode ajudar a explicar os resultados apresentados por Furnariidae são as semelhanças entre a Floresta Ombrófila Mista do sul da BRT e outras florestas temperadas da América do Sul.Variations in richness and abundance of forest ovenbirds (Aves: Furnariidae were studied along an altitudinal/latitudinal gradient of the Tibagi river basin (TRB, southern Brazil. Mixed Temperate Rain Forest (1060 m a.s.l. is the dominant forest in the southern TRB while Seasonal Semideciduous Forest (298 m a.s.l. occurs in the northern. The total number of species obtained in the TRB was 14. Richness and Abundance of Furnariidae were greater in the southern (12 species, IPA = 2.01 than in the northern (five species, IPA = 0.45 TRB. Similarities were also greatest in the southern and in the middle TRB. The community structure of Furnariidae also presented a positive correlation between the southern and the middle TRB (Spearman's rank correlation coefficient; r s = 0.96, r s = 0.89, r s

  9. Weak Learner Method for Estimating River Discharges using Remotely Sensed Data: Central Congo River as a Testbed

    Science.gov (United States)

    Kim, D.; Lee, H.; Yu, H.; Beighley, E.; Durand, M. T.; Alsdorf, D. E.; Hwang, E.

    2017-12-01

    River discharge is a prerequisite for an understanding of flood hazard and water resource management, yet we have poor knowledge of it, especially over remote basins. Previous studies have successfully used a classic hydraulic geometry, at-many-stations hydraulic geometry (AMHG), and Manning's equation to estimate the river discharge. Theoretical bases of these empirical methods were introduced by Leopold and Maddock (1953) and Manning (1889), and those have been long used in the field of hydrology, water resources, and geomorphology. However, the methods to estimate the river discharge from remotely sensed data essentially require bathymetric information of the river or are not applicable to braided rivers. Furthermore, the methods used in the previous studies adopted assumptions of river conditions to be steady and uniform. Consequently, those methods have limitations in estimating the river discharge in complex and unsteady flow in nature. In this study, we developed a novel approach to estimating river discharges by applying the weak learner method (here termed WLQ), which is one of the ensemble methods using multiple classifiers, to the remotely sensed measurements of water levels from Envisat altimetry, effective river widths from PALSAR images, and multi-temporal surface water slopes over a part of the mainstem Congo. Compared with the methods used in the previous studies, the root mean square error (RMSE) decreased from 5,089 m3s-1 to 3,701 m3s-1, and the relative RMSE (RRMSE) improved from 12% to 8%. It is expected that our method can provide improved estimates of river discharges in complex and unsteady flow conditions based on the data-driven prediction model by machine learning (i.e. WLQ), even when the bathymetric data is not available or in case of the braided rivers. Moreover, it is also expected that the WLQ can be applied to the measurements of river levels, slopes and widths from the future Surface Water Ocean Topography (SWOT) mission to be

  10. Removal of congo red and methylene blue from waste water using coagulation

    International Nuclear Information System (INIS)

    Ghaffar, S.; Nosheen, S.; Ahmad, N.

    2011-01-01

    The textile industry has been condemned as being one of the world's worst offenders in terms of pollution Because of increasing population and industrial developments, a huge amount of wastewater is discharged to the environment above the level that the nature can eliminate. Many techniques like oxidation, reduction, physical treatment and biological method are available for removal of colored dyes from wastewater. The work presented here involved the decolorisation of wastewater containing congo red and methylene blue using various coagulants such as alum, bentonite and lime. The effect of various experimental factors such as dosage of coagulants, contact time between coagulant and dye and concentration of dyes and working environment like shaking and static was studied. Under static condition alum give almost 43% removal of congo red while with 10 minutes shaking 74 % removal of 80 dye was achieved with same coagulant. The highest removal of congo red was found to be 99.5 % by using alum after 30 minutes of shaking but in case of methylene blue it intensified the color and gave negative results. Lime gave only 33 % color removal of congo red under static conditions while 57% color was removed under shaking conditions. Maximum color removal achieved by lime was 89% at 40 minutes with shaking condition. Lime gave 60% removal of methylene blue in static condition and 90% removal in shaking condition and maximum absorbance at 80 ppm was 90%. Bentonite also used for the removal of methylene blue and gave 89% removal in shaking condition. By increasing shaking time %age removal increased to 100% at 40 min. And amount of coagulant increased the removal efficiency it attained 100% in both lime and bentonite coagulant for methylene blue Overall alum was found to be better coagulant for the removal of congo red from its aqueous solution. Lime and bentonite both proved better and economical for removal of methylene blue from aqueous solution at lab scale. (author)

  11. The Congo Trap: MONUSCO Islands of Stability in the Sea of Instability

    Directory of Open Access Journals (Sweden)

    Alberto Barrera

    2015-11-01

    Full Text Available 2014 was a hopeful year for the Democratic Republic of Congo (DRC. The M23 movement had been defeated in military operations in which one of the last peacekeeping experiments, the UN Force Intervention Brigade, had played a decisive role. A third UN stabilization plan, the ‘islands of stability’ was proposed to continue the stabilization of a country considered in a post-conflict phase. However, the number of internally displaced persons (IDPs has almost tripled in the country since 2007. This article will argue that DRC is still immersed into an old social conflict that existed before the Congo Wars and the roots of which are not being addressed. It will argue that the United Nations Organization Stabilization Mission in the Democratic Republic of the Congo (MONUSCO and the ‘islands of stability’ strategy can address some of the secondary causes of the Congo conflict, such as its internationalization, the presence in DRC of foreign armed groups or the ‘blood minerals’, but cannot address its primary causes: land struggles, an old cycle of violence and the fragmentation of the Congolese society and political elite that is jeopardizing the restoration of the state authority. The huge dimensions of each of these factors make the Congo conflict ‘one of the most complex and intricate environments ever faced by a peacekeeping mission’, for which MONUSCO’s mandate, resources and stabilization strategy do not seem powerful enough. When the UN organized the 2006 elections legitimized a ‘spoiler state’, the bottleneck of all the reforms needed to stabilize the country. The UN fell thus into a trap and became part of the conflict. Lessons learned should be taken for future UN operations.

  12. DROUGHT ANALYSIS IN OZANA DRAINAGE BASIN

    Directory of Open Access Journals (Sweden)

    Marina IOSUB

    2016-03-01

    Full Text Available Ozana drainage basin is located at the contact between large landscape units (the Carpathian mountains, the Subcarpathian area, and the plateau region. This placement determines the existence of a complex climate in the region. Despite being small in size, and its extension on an W-E direction, differences can be observed, especially of the way extreme phenomena take place. In the case of droughts, it had different intensities in the mountains, compared to the plateau region. In order to emphasize the different distribution on the territory, several climatic indexes have been calculated, regarding dryness (De Martonne Index, Hellman criterion. The analysis of these indexes at the same monitoring stations (Pluton, Leghin and Dumbrava emphasizes the growth of the drought periods in the plateau region and the fact that they shorten in the mountain area. In the mountainous area, where the land is very well forested, the values of the De Martonne index can reach 45.4, and in the plateau regions, where the forest associations are sparse, the values dropped to 30.6. According to the Hellman criterion, several differences can be emphasized, at basin level. In the mountainous region, there is only one month that, at a multi-annual level, has stood up among the rest, as being excessively droughty, while in the median /central region of the basin, three months have been identified, that have such potential, as well as five months, at Dumbrava.

  13. Boreal forests

    International Nuclear Information System (INIS)

    Essen, P.A.; Ericson, L.; Ehnstroem, B.; Sjoeberg, K.

    1997-01-01

    We review patterns and processes important for biodiversity in the Fennoscandian boreal forest, describe man's past and present impact and outline a strategy for conservation. Natural disturbances, particularly forest fire and gap formation, create much of the structural and functional diversity in forest ecosystems. Several boreal plants and animals are adapted to fire regimes. In contrast, many organisms (epiphytic lichens, fungi, invertebrates) require stable conditions with long continuity in canopy cover. The highly mechanized and efficient Fennoscandian forest industry has developed during the last century. The result is that most natural forest has been lost and that several hundreds of species, mainly cryptograms and invertebrates, are threatened. The forestry is now in a transition from exploitation to sustainable production and has recently incorporated some measures to protect the environment. Programmes for maintaining biodiversity in the boreal forest should include at least three parts. First, the system of forest reserves must be significantly improved through protection of large representative ecosystems and key biotopes that host threatened species. Second, we must restore ecosystem properties that have been lost or altered. Natural disturbance regimes must be allowed to operate or be imitated, for example by artificial fire management. Stand-level management should particularly increase the amount of coarse woody debris, the number of old deciduous trees and large, old conifers, by using partial cutting. Third, natural variation should also be mimicked at the landscape level, for example, by reducing fragmentation and increasing links between landscape elements. Long-term experiments are required to evaluate the success of different management methods in maintaining biodiversity in the boreal forest. (au) 260 refs

  14. Contribution to the geology of the Niari basin: sedimentology and metallogeny of the mining region; Contribution a la geologie du Bassin du Niari sedimentologie et metallogenie de la region miniere

    Energy Technology Data Exchange (ETDEWEB)

    Bigotte, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1956-01-15

    This thesis is divided in two parts: a detailed petrographical and stratigraphical study of the upper layers of calcareous schist in Congo which lead to some sedimentological considerations, and a metallogenic study of the ores of Niari basin which lead to a theoretical description of the metallogeny in Congo. In the first part, after a brief description of the methods used, a petrographical survey of the rocks of the upper layers of calcareous schist of the Boko-Congo area is given as well as sedimentological conclusions and stratigraphical data. The studies and conclusions related to this limited area are extended to a region scale. A structural study and precised descriptions of this region lead to an attempt of tectonic explanation. In the second part, an inventory and description of known mineralisation points in the Niari basin are given and in particular the detailed descriptions of four deposits: La Grande-Mine, M'Passa, Diangala and Djenguile. The interpretations and conclusions are based on the study of the general characters of the mineralisation in Niari basin and its comparison with the mineralisation in Katanga (now Shaba region) and North Rhodesia (now Zambia). (M.P.)

  15. Contribution to the geology of the Niari basin: sedimentology and metallogeny of the mining region; Contribution a la geologie du Bassin du Niari sedimentologie et metallogenie de la region miniere

    Energy Technology Data Exchange (ETDEWEB)

    Bigotte, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1956-01-15

    This thesis is divided in two parts: a detailed petrographical and stratigraphical study of the upper layers of calcareous schist in Congo which lead to some sedimentological considerations, and a metallogenic study of the ores of Niari basin which lead to a theoretical description of the metallogeny in Congo. In the first part, after a brief description of the methods used, a petrographical survey of the rocks of the upper layers of calcareous schist of the Boko-Congo area is given as well as sedimentological conclusions and stratigraphical data. The studies and conclusions related to this limited area are extended to a region scale. A structural study and precised descriptions of this region lead to an attempt of tectonic explanation. In the second part, an inventory and description of known mineralisation points in the Niari basin are given and in particular the detailed descriptions of four deposits: La Grande-Mine, M'Passa, Diangala and Djenguile. The interpretations and conclusions are based on the study of the general characters of the mineralisation in Niari basin and its comparison with the mineralisation in Katanga (now Shaba region) and North Rhodesia (now Zambia). (M.P.)

  16. Amazon forest response to repeated droughts

    Science.gov (United States)

    Feldpausch, T. R.; Phillips, O. L.; Brienen, R. J. W.; Gloor, E.; Lloyd, J.; Lopez-Gonzalez, G.; Monteagudo-Mendoza, A.; Malhi, Y.; Alarcón, A.; Álvarez Dávila, E.; Alvarez-Loayza, P.; Andrade, A.; Aragao, L. E. O. C.; Arroyo, L.; Aymard C., G. A.; Baker, T. R.; Baraloto, C.; Barroso, J.; Bonal, D.; Castro, W.; Chama, V.; Chave, J.; Domingues, T. F.; Fauset, S.; Groot, N.; Honorio Coronado, E.; Laurance, S.; Laurance, W. F.; Lewis, S. L.; Licona, J. C.; Marimon, B. S.; Marimon-Junior, B. H.; Mendoza Bautista, C.; Neill, D. A.; Oliveira, E. A.; Oliveira dos Santos, C.; Pallqui Camacho, N. C.; Pardo-Molina, G.; Prieto, A.; Quesada, C. A.; Ramírez, F.; Ramírez-Angulo, H.; Réjou-Méchain, M.; Rudas, A.; Saiz, G.; Salomão, R. P.; Silva-Espejo, J. E.; Silveira, M.; ter Steege, H.; Stropp, J.; Terborgh, J.; Thomas-Caesar, R.; van der Heijden, G. M. F.; Vásquez Martinez, R.; Vilanova, E.; Vos, V. A.

    2016-07-01

    The Amazon Basin has experienced more variable climate over the last decade, with a severe and widespread drought in 2005 causing large basin-wide losses of biomass. A drought of similar climatological magnitude occurred again in 2010; however, there has been no basin-wide ground-based evaluation of effects on vegetation. We examine to what extent the 2010 drought affected forest dynamics using ground-based observations of mortality and growth from an extensive forest plot network. We find that during the 2010 drought interval, forests did not gain biomass (net change: -0.43 Mg ha-1, confidence interval (CI): -1.11, 0.19, n = 97), regardless of whether forests experienced precipitation deficit anomalies. This contrasted with a long-term biomass sink during the baseline pre-2010 drought period (1998 to pre-2010) of 1.33 Mg ha-1 yr-1 (CI: 0.90, 1.74, p history. Thus, there was no evidence that pre-2010 droughts compounded the effects of the 2010 drought. We detected a systematic basin-wide impact of the 2010 drought on tree growth rates across Amazonia, which was related to the strength of the moisture deficit. This impact differed from the drought event in 2005 which did not affect productivity. Based on these ground data, live biomass in trees and corresponding estimates of live biomass in lianas and roots, we estimate that intact forests in Amazonia were carbon neutral in 2010 (-0.07 Pg C yr-1 CI:-0.42, 0.23), consistent with results from an independent analysis of airborne estimates of land-atmospheric fluxes during 2010. Relative to the long-term mean, the 2010 drought resulted in a reduction in biomass carbon uptake of 1.1 Pg C, compared to 1.6 Pg C for the 2005 event.

  17. Bird community in a forest patch isolated by the urban matrix at the Sinos River basin, Rio Grande do Sul state, Brazil, with comments on the possible local defaunation

    Directory of Open Access Journals (Sweden)

    I. Franz

    Full Text Available We compared the avifauna recorded in a recent survey in an urban park (Parque Municipal Henrique Luís Roessler, Parcão and surroundings, Novo Hamburgo, RS, with past data, to evaluate the possible alterations in species composition over time. Of the 265 species compiled as original elements of that region, 114 were found at Parcão. Among forest species, 37% were considered locally extinct. The most affected guild was the large frugivores, with nine extinct species and one survivor (Trogon surrucura. Birds highly sensitive to disturbance as well as endemic species were the most extinguished. The possible causes for this loss are fragmentation, hunting and environmental changes. The diversity today is threatened, thus conservation measures are necessary in that region. The most important actions are: maintenance of ecological corridors, protection of natural remnant areas and the establishment of protected areas.

  18. Secondary Forests from Agricultural Abandonment in Amazonia 2000-2009

    Science.gov (United States)

    Morton, Douglas

    2010-01-01

    Ongoing negotiations to include reducing emissions from tropical deforestation and forest degradation (REDD+) in a post-Kyoto climate agreement highlight the critical role of satellite data for accurate and transparent accounting of forest cover changes. In addition to deforestation and degradation, knowledge of secondary forest dynamics is essential for full carbon accounting under REDD+. Land abandonment to secondary forests also frames one of the key tradeoffs for agricultural production in tropical forest countries-whether to incentivize secondary forest growth (for carbon sequestration and biodiversity conservation) or low-carbon expansion of agriculture or biofuels production in areas of secondary forests. We examined patterns of land abandonment to secondary forest across the arc of deforestation in Brazil and Bolivia using time series of annual Landsat and MODIS data from 2000-2009. Rates of land abandonment to secondary forest during 2002-2006 were less than 5% of deforestation rates in these years. Small areas of new secondary forest were scattered across the entire arc of deforestation, rather than concentrated in any specific region of the basin. Taken together, our analysis of the satellite data record emphasizes the difficulties of addressing the pool of new secondary forests in the context of REDD+ in Amazonia. Due to the small total area of secondary forests, land sparing through agricultural intensification will be an important element of efforts to reduce deforestation rates under REDD+ while improving agricultural productivity in Amazonia.

  19. Descriptive models, grade-tonnage relations, and databases for the assessment of sediment-hosted copper deposits: with emphasis on deposits in the Central Africa Copperbelt, Democratic Republic of the Congo and Zambia: Chapter J in Global mineral resource assessment

    Science.gov (United States)

    Taylor, Cliff D.; Causey, J. Douglas; Denning, Paul; Hammarstrom, Jane M.; Hayes, Timothy S.; Horton, John D.; Kirschbaum, Michael J.; Parks, Heather L.; Wilson, Anna B.; Wintzer, Niki E.; Zientek, Michael L.

    2013-01-01

    The Central African Copperbelt (CACB) is one of the most important copper-producing regions of the world. The majority of copper produced in Africa comes from this region defined by the Neoproterozoic Katanga sedimentary basin of the southern Democratic Republic of the Congo (DRC) and northern Zambia. Copper in the CACB is mined from sediment-hosted stratabound copper deposits associated with red beds and includes the giant deposits in the Kolwezi and Tenge-Fungurume districts in the DRC and the Konkola-Musoshi and Nchanga-Chingola districts in Zambia. In recent years, sediment-hosted structurally controlled replacement and vein (SCRV) copper deposits, such as the giant Kansanshi deposit in Zambia have become important exploration targets in the CACB region.

  20. Electromagnetic evidence of high angle convergence between the Congo and Kalahari cratons in southern Africa

    Science.gov (United States)

    Khoza, D. T.; Jones, A. G.; Muller, M. R.; Miensopust, M. P.; Webb, S. J.; Share, P.

    2010-12-01

    The southern African tectonic fabric is made up of a number Archean cratons flanked by Proterozoic and younger mobile belts, all with distinctly different but related geological evolutions. The cratonic margins and some intra-cratonic domain boundaries have played major roles in the tectonics of Africa by focusing ascending magmas and localising cycles of extension and rifting. Of these cratons the southern extent of the Congo craton is one of the least-constrained tectonic boundaries in the African tectonic architecture and knowledge of its geometry is crucial for understanding geological process of formation and deformation prevailing in the Archean and later. In this work, which forms a component of the hugely successful Southern African MagnetoTelluric Experiment (SAMTEX), we present the first-ever lithospheric electrical resistivity image of the southern boundary of the enigmatic Congo craton and the Neoproterozoic Damara-Ghanzi-Chobe (DGC) orogenic belt on its flanks. The DGC belt is highly complex and records the transpressive collision between the Congo to the north and Kalahari craton to the south. Magnetotelluric data were collected along a profile crossing all three of these tectonic blocks. The two-dimensional resistivity models resulting from inverting the distortion-corrected responses along the profiles all indicate significant lateral variations in the crust and upper mantle structure along and across strike from the younger DGC orogen to the older adjacent craton. The Moho depth in the DGC is mapped at 40 km by active seismic methods, and is also well constrained by S-wave receiver function models. The Damara belt lithosphere, although generally more conductive and significantly thinner (approximately 150 km) than the adjacent Congo and Kalahari cratons, exhibits upper crustal resistive features interpreted to be caused by igneous intrusions emplaced during the Gondwanan Pan-African magmatic event. The thinned lithosphere is consistent with a 50 m

  1. Incorporação de indicadores de sustentabilidade na priorização de áreas para restauração florestal na bacia do rio Corumbataí, SP Incorporating sustainability indicators on site selection for forest restoration in the Corumbataí river basin

    Directory of Open Access Journals (Sweden)

    Silvio Frosini de Barros Ferraz

    2009-10-01

    Full Text Available Na bacia do rio Corumbataí, a vegetação natural ocupa menos de 3% de sua área total, e a ausência dessa vegetação florestal tem levado ao aumento dos processos erosivos e ao desequilíbrio do regime hídrico de seus rios, causando diversos problemas no abastecimento de água de várias cidades, como Piracicaba e Rio Claro. Desse modo, existe a necessidade de um reflorestamento criterioso em áreas dessa bacia. No entanto, devido à limitação de recursos, é necessário que sejam realizados estudos de seleção de áreas prioritárias para que, com os recursos disponíveis, o ganho ambiental das áreas restauradas seja máximo. O objetivo deste trabalho foi desenvolver um método de priorização de áreas para restauração florestal baseado no uso de indicadores de sustentabilidade em microbacias. Cinco indicadores foram utilizados: porcentagem de mata nativa na APP; descontinuidade da vegetação nativa na bacia; diversidade da paisagem; variação média do uso da terra; e suscetibilidade à erosão. A seleção das microbacias para restauração das áreas de APP foi realizada por meio da ponderação linear dos indicadores e ordenamento das microbacias. Simulação inicial foi realizada para a seleção de 1.000 ha para restauração, e os resultados indicaram que os indicadores representam diferentes aspectos de sustentabilidade das microbacias. O método foi considerado útil na seleção de microbacias em condições extremas, diferenciando aquelas que necessitam de ações de conservação daquelas que necessitam de ações de restauração.In the Corumbataí river basin, State of São Paulo, forest remnants occupy less than 3% of the original total area, and the absence of this natural vegetation has been increasing erosion and disturbing hydrological regime of its streams, causing many problems on water supply in urban areas like Piracicaba and Rio Claro. This situation shows the need of a well planned reforestation in areas

  2. Gestion participative du sanctuaire de gorilles de plaine de l'ouest (Gorilla gorilla gorilla de Lossi en République du Congo- Brazzaville: première analyse de résultats et des contraintes

    Directory of Open Access Journals (Sweden)

    Mbété, RA.

    2007-01-01

    Full Text Available Participative Management of the Sanctuary of Western Lowland Gorillas (Gorilla gorilla gorilla of Lossi in Republic of Congo-Brazzaville: Preliminary Results and Constraints Analysis. The gorilla sanctuary of Lossi experiments the synergy between scientific research and nature conservation. Three partners are involved in a management participative process. These partners include the Republic of Congo, the local community of Lossi and the European programme on the forest ecosystems in Central Africa. An investigation was carried out on the sanctuary of Lossi in 2003, in order to study in situ the effects generated by the participative management and to identify the constraints linked to the participative approach. The work of primatologists allowed the habituation of the gorillas to the human presence and opened eyesight tourism of western lowland gorillas. A camp for tourists and the access road to the sanctuary have been constructed. The tourism generated jobs in favour of the local population which is also a take-partner of contracts on road repairing. The income from the tourism allowed the construction of a health centre. However, the works of researchers and tourism activities failed during the outbreaks of the Ebola hemorrhagic fever and during the three civil war episodes. The consolidation and the long term of this process of co-management of natural resources of Lossi remains the establishment of a management that should include conservation, rural development and scientific research, with equitably in the distribution of gain between the partnerses.

  3. Bacteria diversity and microbial biomass in forest, pasture and fallow soils in the southwestern Amazon basin Diversidade de bacteria e biomassa microbiana em solos sob floresta, pastagem e capoeira no sudoeste da Amazônia

    Directory of Open Access Journals (Sweden)

    Karina Cenciani

    2009-08-01

    Full Text Available It is well-known that Amazon tropical forest soils contain high microbial biodiversity. However, anthropogenic actions of slash and burn, mainly for pasture establishment, induce profound changes in the well-balanced biogeochemical cycles. After a few years the grass yield usually declines, the pasture is abandoned and is transformed into a secondary vegetation called "capoeira" or fallow. The aim of this study was to examine how the clearing of Amazon rainforest for pasture affects: (1 the diversity of the Bacteria domain evaluated by Polymerase Chain Reaction and Denaturing Gradient Gel Electrophoresis (PCR-DGGE, (2 microbial biomass and some soil chemical properties (pH, moisture, P, K, Ca, Mg, Al, H + Al, and BS, and (3 the influence of environmental variables on the genetic structure of bacterial community. In the pasture soil, total carbon (C was between 30 to 42 % higher than in the fallow, and almost 47 % higher than in the forest soil over a year. The same pattern was observed for N. Microbial biomass in the pasture was about 38 and 26 % higher than at fallow and forest sites, respectively, in the rainy season. DGGE profiling revealed a lower number of bands per area in the dry season, but differences in the structure of bacterial communities among sites were better defined than in the wet season. The bacterial DNA fingerprints in the forest were stronger related to Al content and the Cmic:Ctot and Nmic:Ntot ratios. For pasture and fallow sites, the structure of the Bacteria domain was more associated with pH, sum of bases, moisture, total C and N and the microbial biomass. In general microbial biomass in the soils was influenced by total C and N, which were associated with the Bacteria domain, since the bacterial community is a component and active fraction of the microbial biomass. Results show that the genetic composition of bacterial communities in Amazonian soils changed along the sequence forest-pasture-fallow.Os solos da floresta

  4. Basalt stratigraphy - Pasco Basin

    International Nuclear Information System (INIS)

    Waters, A.C.; Myers, C.W.; Brown, D.J.; Ledgerwood, R.K.

    1979-10-01

    The geologic history of the Pasco Basin is sketched. Study of the stratigraphy of the area involved a number of techniques including major-element chemistry, paleomagnetic investigations, borehole logging, and other geophysical survey methods. Grande Ronde basalt accumulation in the Pasco Basin is described. An illustrative log response is shown. 1 figure

  5. Melo carboniferous basin

    International Nuclear Information System (INIS)

    Flossdarf, A.

    1988-01-01

    This report is about of the Melo carboniferous basin which limits are: in the South the large and high Tupambae hill, in the west the Paraiso hill and the river mountains, in the North Yaguaron river basin to Candidata in Rio Grande del Sur in Brazil.

  6. Basin Hopping Graph

    DEFF Research Database (Denmark)

    Kucharik, Marcel; Hofacker, Ivo; Stadler, Peter

    2014-01-01

    of the folding free energy landscape, however, can provide the relevant information. Results We introduce the basin hopping graph (BHG) as a novel coarse-grained model of folding landscapes. Each vertex of the BHG is a local minimum, which represents the corresponding basin in the landscape. Its edges connect...

  7. Sobrevivência de plântulas transplantadas de uma floresta tropical madura para viveiro de mudas na bacia do rio Xingu. Survival of seedlings transplanted from a mature tropical forest to nursery in Xingu river basin.

    Directory of Open Access Journals (Sweden)

    Roberta Thays dos Santos CURY

    2013-06-01

    Full Text Available A utilização da diversidade de plântulas de espécies arbóreas, oriundas de áreas cuja vegetação teve a supressão autorizada, no enriquecimento de viveiros, tem sido recomendada como uma técnica alternativa na produção de mudas. Neste trabalho, avaliamos a sobrevivência de plântulas transplantadas da regeneração natural de uma floresta madura para um viveiro de mudas em uma área de transição Amazônia-Cerrado, Mato Grosso, Brasil. Foram alocados três transectos de 10 x 1 m, com 10, 50 e 500 m de distância da borda de onde foram coletados todos os indivíduos lenhosos entre 5-20 cm de altura, no período da manhã (7h às 9h, e sequencialmente plantados em sacos plásticos. Os indivíduos foram identificados, quantificados e classificados quanto ao estágio sucessional. A sobrevivência das plântulas foi avaliada durante quatro meses. No total foram coletados 1.179 indivíduos arbóreos pertencentes a 48 espécies, 31 gêneros e 23 famílias, dos quais 71% sobreviveram. No conjunto dos dados, houve um aumento gradativo na abundância e riqueza de espécies arbóreas da borda para o interior da floresta, sendo maior a 500 m. A abundância e o número de espécies não pioneiras coletadas foram maiores que as pioneiras. Os resultados apontam elevadas taxas de sobrevivência e que a técnica de transplante pode facilitar o enriquecimento de viveiros com espécies regionais de difícil obtenção e de diferentes grupos funcionais. The use of the diversity of tree species, present in areas where vegetation removal had been authorized, as means of nursery enrichment, has been recommended as an alternative technique for seedling production. The aim of this study was to evaluate the survival rate of transplanted seedlings, from natural regeneration in mature forests, to the nursery. Seedlings were obtained from three 10 x 1 m transects allocated in Amazon transitional forest in Mato Grosso state, Brazil. All woody individuals with

  8. K Basin safety analysis

    International Nuclear Information System (INIS)

    Porten, D.R.; Crowe, R.D.

    1994-01-01

    The purpose of this accident safety analysis is to document in detail, analyses whose results were reported in summary form in the K Basins Safety Analysis Report WHC-SD-SNF-SAR-001. The safety analysis addressed the potential for release of radioactive and non-radioactive hazardous material located in the K Basins and their supporting facilities. The safety analysis covers the hazards associated with normal K Basin fuel storage and handling operations, fuel encapsulation, sludge encapsulation, and canister clean-up and disposal. After a review of the Criticality Safety Evaluation of the K Basin activities, the following postulated events were evaluated: Crane failure and casks dropped into loadout pit; Design basis earthquake; Hypothetical loss of basin water accident analysis; Combustion of uranium fuel following dryout; Crane failure and cask dropped onto floor of transfer area; Spent ion exchange shipment for burial; Hydrogen deflagration in ion exchange modules and filters; Release of Chlorine; Power availability and reliability; and Ashfall

  9. Illinois' Forests 2005

    Science.gov (United States)

    Susan J. Crocker; Gary J. Brand; Brett J. Butler; David E. Haugen; Dick C. Little; Dacia M. Meneguzzo; Charles H. Perry; Ronald J. Piva; Barry T. Wilson; Christopher W. Woodall

    2009-01-01

    The first full, annualized inventory of Illinois' forests reports more than 4.5 million acres of forest land with an average of 459 trees per acre. Forest land is dominated by oak/hickory forest types, which occupy 65 percent of total forest land area. Seventy-two percent of forest land consists of sawtimber, 20 percent contains poletimber, and 8 percent contains...

  10. Minnesota's Forests 2008

    Science.gov (United States)

    Patrick D. Miles; David Heinzen; Manfred E. Mielke; Christopher W. Woodall; Brett J. Butler; Ron J. Piva; Dacia M. Meneguzzo; Charles H. Perry; Dale D. Gormanson; Charles J. Barnett

    2011-01-01

    The second full annual inventory of Minnesota's forests reports 17 million acres of forest land with an average volume of more than 1,000 cubic feet per acre. Forest land is dominated by the aspen forest type, which occupies nearly 30 percent of the total forest land area. Twenty-eight percent of forest land consists of sawtimber, 35 percent poletimber, 35 percent...

  11. CONDITIONS FOR TECHNOLOGY TRANSFER IN THE AGRICULTURE OF CONGO REPUBLIC*

    Directory of Open Access Journals (Sweden)

    Katarzyna Andrzejczak

    2017-03-01

    Full Text Available The majority of the population in Sub-Saharan Africa is employed in agriculture. Nevertheless, the productivity of the sector is relatively low in comparison with other regions of the world. Based on convergence theory, technology transfer can enhance growth. However, the effective transfer of technology requires a certain absorption capacity from the recipient. Based on the qualitative research on cassava production in Congo Brazzaville, we identified key factors that influence the transfer process. These factors have been divided into four key areas: market, institutions, technology, and social capability. Cassava production value chain in Ignie region served as a case study for the evaluation of technology transfer absorptive capacity in Congo agriculture. We learned that the lack of agro-technical education, shortages in infrastructure, unavailability of business services, and market structure are among the main barriers of the intensification of technology use in agriculture.

  12. Gravity Data Interpretation in the Northern Edge of the Congo Craton, South-Cameroon

    Directory of Open Access Journals (Sweden)

    James Derek Fairhead

    2010-01-01

    Full Text Available Gravity data in the southern Cameroon are interpreted to better understand the organization of underlying structuresthroughout the northern edge of the Congo craton. The Bouguer anomaly maps of the region are characterized by an elongated trending trending negative gravity anomaly which correspond to a collapsed structure associated with a granitic intrusion beneath the cente center of the region r of the region of the region and limited by fault systems. �e applied 3�D gravity modelling and inversion in order to obtain the 3D density structure of the area. Our result demonstrated that observed gravity anomalies in the region are associated to tectonic structures in the subsurface. The resulting model agrees with the hypothesis of the existence of a major continental collision zone between the Congo Craton and the Pan�African belt. The presence of deep granulites structures in the northern part of the region expresses a continental collision.

  13. Removal of Congo Red from Aqueous Solution by Anion Exchange Membrane (EBTAC): Adsorption Kinetics and Themodynamics

    Science.gov (United States)

    Khan, Muhammad Imran; Akhtar, Shahbaz; Zafar, Shagufta; Shaheen, Aqeela; Khan, Muhammad Ali; Luque, Rafael; ur Rehman, Aziz

    2015-01-01

    The adsorption behavior of anionic dye congo red (CR) from aqueous solutions using an anion exchange membrane (EBTAC) has been investigated at room temperature. The effect of several factors including contact time, membrane dosage, ionic strength and temperature were studied. Kinetic models, namely pseudo-first-order and pseudo-second-order, liquid film diffusion and Elovich models as well as Bangham and modified freundlich Equations, were employed to evaluate the experimental results. Parameters such as adsorption capacities, rate constant and related correlation coefficients for every model were calculated and discussed. The adsorption of CR on anion exchange membranes followed pseudo-second-order Kinetics. Thermodynamic parameters, namely changes in Gibbs free energy (∆G°), enthalpy (∆H°) and entropy (∆S°) were calculated for the adsorption of congo red, indicating an exothermic process. PMID:28793430

  14. [Synthesis and Study on Adsorption Property of Congo Red Molecularly Imprinted Polymer Nanospheres].

    Science.gov (United States)

    Chang, Zi-qiang; Chen, Fu-bin; Zhang, Yu; Shi, Zuo-long; Yang, Chun-yan; Zhang, Zhu-jun

    2015-07-01

    Molecularly imprinted polymer nanospheres (MIP) were prepared with Congo red as the template, methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as the cross linker, azodiisobutyronitrile (AIBN) as an initiator, and acetonitrile as the porogen by precipitation polymerization. The morphology of MIP was characterized by SEM and TEM which showed that the diameter of MIP was nanometer grade (90 nm) and the shape was homogeneous. The specific surface area and pore volumes of MIP and NIP were examined through Brunauer-Emett-Teller method of nitrogen adsorption experiments. Then, the adsorption and selective recognition ability of MIPs were evaluated using the equilibrium rebinding experiments. The results indicated that the prepared MIP showed a good selectivity recognition ability to its template. It concluded that MIP could be employed as an effective material for removing Congo red from waste water.

  15. Synthesis, Characterization and Adsorption Capability of CdO Microstructure for Congo Red from Aqueous Solution

    Directory of Open Access Journals (Sweden)

    A. Tadjarodi

    2012-03-01

    Full Text Available Cadmium oxide rhombus-shaped nanostructure was synthesized using hydrothermal process followed by heating treatment. Clearly, X-ray diffraction pattern demonstrated the formation of CdO crystalline phase. Scanning electron microscopy (SEM showed that the obtained rhombus-like structure is composed of nanoparticles with the average size of 29 nm. In addition, we evaluated adsorption of organic dye i.e. Congo red from water using the prepared CdO rhombus like microstructure. UV-visible absorption spectroscopy was used to record the adsorption behavior. It was found that the removal process is performed via electrostatic absorption mechanism. The maximum adsorption capacity of CdO rhombus structures (0.01 g for Congo Red (CR in the concentration range (5-50 mg L-1 studied, as calculated from the Langmuir isotherm model at 25 ˚C and neutral pH, was found to be 41.20 mg g−1 .

  16. Village Stability Operations in the Democratic Republic of Congo: A Special Operations Approach

    Science.gov (United States)

    2014-12-12

    effects .8 In addition to these deaths, the UN reports 2.9 million 7 The eleven nations: DRC, Republic of Congo , Uganda, Rwanda , Burundi, Angola, Namibia...Lakes region of Central Africa on land that is easy to exploit but difficult to control. Since the 1994 genocide in Rwanda , which prompted massive...incumbent Hutu government in neighboring Rwanda initiated a genocide of the Tutsi population. The Tutsi Rwanda Patriotic Front (RPF) capitalized on the

  17. Crimean Congo Hemorrhagic Fever Virus and Alkhurma (Alkhumra) Virus in Ticks in Djibouti.

    Science.gov (United States)

    Horton, Katherine C; Fahmy, Nermeen T; Watany, Noha; Zayed, Alia; Mohamed, Abro; Ahmed, Ammar Abdo; Rollin, Pierre E; Dueger, Erica L

    2016-10-01

    Crimean Congo hemorrhagic fever virus and Alkhumra virus, not previously reported in Djibouti, were detected among 141 (infection rate = 15.7 per 100, 95% CI: 13.4-18.1) tick pools from 81 (37%) cattle and 2 (infection rate = 0.2 per 100, 95% CI: 0.0-0.7) tick pools from 2 (1%) cattle, respectively, collected at an abattoir in 2010 and 2011.

  18. Violence against sex workers by police and military in Democratic Republic of Congo.

    Science.gov (United States)

    Ombeni, Alphonse Mihigo; Crago, Anna Louise

    2008-12-01

    Sex workers in the Sud-Kivu district of the Democratic Republic of Congo (DRC) are regularly subjected to sexual and other forms of violence. In this article, based on a presentation at a concurrent session at the conference, Alphonse Mihigo Ombeni and Anna Louise Crago describe the negative impacts of this violence on the sex workers' health and working conditions. Many have become HIV-positive.

  19. Isotherm, Kinetic and Thermodynamic Characteristics for Adsorption of Congo Red by Activated Carbon

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Jib [Kongju National University, Cheonan (Korea, Republic of)

    2015-02-15

    Batch experiment studies were carried out for adsorption of congo red using granular activated carbon with various parameters such as activated carbon dose, pH, initial dye concentration, temperature and contact time. Equilibrium experimental data are fitted to the Langmuir, Freundlich, Temkin and Dubin-Radushkevich isotherm equations. From Freundlich's separation factor (1/n) estimated, adsorption could be employed as effective treatment method for adsorption of congo red from aqueous solution. Base on Temkin constant (B) and Dubinin-Radushkevich constant (E), this adsorption process is physical adsorption. Adsorption kinetics has been tested using pseudo-first order and pseudo second order models. The results followed pseudo second order model with good correlation. Adsorption process of congo red on granular activated carbon was endothermic (ΔH=42.036 kJ/mol) and was accompanied by decrease in Gibbs free energy (ΔG=-2.414 to -4.596 kJ/mol) with increasing adsorption temperature.

  20. Isotherm, Kinetic and Thermodynamic Characteristics for Adsorption of Congo Red by Activated Carbon

    International Nuclear Information System (INIS)

    Lee, Jong Jib

    2015-01-01

    Batch experiment studies were carried out for adsorption of congo red using granular activated carbon with various parameters such as activated carbon dose, pH, initial dye concentration, temperature and contact time. Equilibrium experimental data are fitted to the Langmuir, Freundlich, Temkin and Dubin-Radushkevich isotherm equations. From Freundlich's separation factor (1/n) estimated, adsorption could be employed as effective treatment method for adsorption of congo red from aqueous solution. Base on Temkin constant (B) and Dubinin-Radushkevich constant (E), this adsorption process is physical adsorption. Adsorption kinetics has been tested using pseudo-first order and pseudo second order models. The results followed pseudo second order model with good correlation. Adsorption process of congo red on granular activated carbon was endothermic (ΔH=42.036 kJ/mol) and was accompanied by decrease in Gibbs free energy (ΔG=-2.414 to -4.596 kJ/mol) with increasing adsorption temperature

  1. Synthesis of Magnesium Ferrites for the Adsorption of Congo Red from Aqueous Solution Using Batch Studies

    Science.gov (United States)

    Erdawati, E.; Darsef, D.

    2018-04-01

    A sol gel method with citric acid as an anionic surfactant was used to fabricate nano magnesium ferrites (MgFe2O4) under different calcination temperatures for 2h, respectively. The microstructure and surface morphology of magnesium ferrite powder were characterized by FTIR, XRD, SEM, and BET. The results of this study are useful for adsorption Congo red. The results showed that increasing solution pH and extending contact time are favorable for improving adsorption efficiency. with initial Congo red concentration of 50 mg/L and 100 mg/L. Adsorption data fits well with the Langmuir isotherm models with a maximum adsorption capacity (qm) and a Langmuir adsorption equilibrium constant (K) of 65.1 mg/g and 0.090 L/mg, respectively. The adsorption kinetic agrees well with pseudo second order model with the pseudo second rate constants (K2) of 0.0468 and0.00189 g/mg/min for solutions with initial congo red of 50 and 100 mg/L, respectively

  2. Dinâmica do ecótono floresta-campo no sul do estado do Amazonas no Holoceno, através de estudos isotópicos e fitossociológicos Vegetation dynamics during the Holocene in a forest-savanna transition, Southern Amazon Basin, based on isotope and phytosociological studies

    Directory of Open Access Journals (Sweden)

    Elaine Vidotto

    2007-01-01

    Full Text Available Com o emprego dos isótopos do carbono (12C, 13C, 14C da matéria orgânica do solo (MOS e das plantas, é apresentado um estudo comparativo entre perfis orgânicos de solos formados em depressões de áreas cobertas por ecossistemas de campos e florestas ao sul do estado do Amazonas, visando o entendimento da dinâmica da paleovegetação. A dinâmica da vegetação atual na região foi avaliada utilizando-se estudos fitossociológicos e caracterizações botânica e isotópica (delta13C das espécies de plantas presentes em duas bordas floresta-campo. Teores de carbono orgânico total foram superiores nas camadas superficiais no campo, quando comparados com a floresta. Dados de delta13C associados à cronologia do 14C indicaram predomínio de plantas C3 no início do Holoceno em ambos os ecótonos. Entre aproximadamente 7.000-3.000 anos AP verificou-se a influência crescente de plantas C4, indicando regressão da floresta com possível presença de um clima mais seco. A partir de aproximadamente 3.000 anos AP os dados sugeriram expansão da floresta provavelmente relacionada ao retorno a um clima mais úmido. A presença de algumas espécies características da borda, como a Sclerolobium paniculatum e Himatanthus sucuuba, nos campos, sugere o atual avanço da floresta sobre os mesmos. Estas espécies estariam sendo as bioindicadoras desse avanço.This paper presents a comparative study between organic soil horizons formed in depressions located at the forest/savanna boundary in the Southern Amazon Basin. The influence of the paleovegetation dynamics, based on carbon isotope (12C, 13C and 14C data of soil organic matter (SOM and plants was evaluated, as well as the present vegetation dynamics, inferred from the modern vegetation structure, composition and phytosociology. The uppermost soil horizon in savanna showed higher total carbon content than in forest. 13C and 14C data from soil samples indicated a predominance of C3 plants in the early

  3. The Ogaden Basin, Ethiopia: an underexplored sedimentary basin

    Energy Technology Data Exchange (ETDEWEB)

    Teitz, H.H.

    1991-01-01

    A brief article examines the Ogaden Basin in Ethiopia in terms of basin origin, basin fill and the hydrocarbon exploration history and results. The natural gas find in pre-Jurassic sandstones, which appears to contain substantial reserves, justifies continuing investigations in this largely underexplored basin. (UK).

  4. Climate-driven disturbances in the San Juan River sub-basin of the Colorado River

    Science.gov (United States)

    Bennett, Katrina E.; Bohn, Theodore J.; Solander, Kurt; McDowell, Nathan G.; Xu, Chonggang; Vivoni, Enrique; Middleton, Richard S.

    2018-01-01

    Accelerated climate change and associated forest disturbances in the southwestern USA are anticipated to have substantial impacts on regional water resources. Few studies have quantified the impact of both climate change and land cover disturbances on water balances on the basin scale, and none on the regional scale. In this work, we evaluate the impacts of forest disturbances and climate change on a headwater basin to the Colorado River, the San Juan River watershed, using a robustly calibrated (Nash-Sutcliffe efficiency 0.76) hydrologic model run with updated formulations that improve estimates of evapotranspiration for semi-arid regions. Our results show that future disturbances will have a substantial impact on streamflow with implications for water resource management. Our findings are in contradiction with conventional thinking that forest disturbances reduce evapotranspiration and increase streamflow. In this study, annual average regional streamflow under the coupled climate-disturbance scenarios is at least 6-11 % lower than those scenarios accounting for climate change alone; for forested zones of the San Juan River basin, streamflow is 15-21 % lower. The monthly signals of altered streamflow point to an emergent streamflow pattern related to changes in forests of the disturbed systems. Exacerbated reductions of mean and low flows under disturbance scenarios indicate a high risk of low water availability for forested headwater systems of the Colorado River basin. These findings also indicate that explicit representation of land cover disturbances is required in modeling efforts that consider the impact of climate change on water resources.

  5. The global extent and determinants of savanna and forest as alternative biome states.

    Science.gov (United States)

    Staver, A Carla; Archibald, Sally; Levin, Simon A

    2011-10-14

    Theoretically, fire-tree cover feedbacks can maintain savanna and forest as alternative stable states. However, the global extent of fire-driven discontinuities in tree cover is unknown, especially accounting for seasonality and soils. We use tree cover, climate, fire, and soils data sets to show that tree cover is globally discontinuous. Climate influences tree cover globally but, at intermediate rainfall (1000 to 2500 millimeters) with mild seasonality (less than 7 months), tree cover is bimodal, and only fire differentiates between savanna and forest. These may be alternative states over large areas, including parts of Amazonia and the Congo. Changes in biome distributions, whether at the cost of savanna (due to fragmentation) or forest (due to climate), will be neither smooth nor easily reversible.

  6. Ecophysiology of a Mangrove Forest in Jobos Bay, Puerto Rico

    Science.gov (United States)

    ARIEL E. LUGO; ERNESTO MEDINA; ELVIRA CUEVAs; CINTR& #211; GILBERTO N; EDDIE N. LABOY NIEVES; SCH& #196; YARA EFFER NOVELLI

    2007-01-01

    We studied gas exchange, leaf dimensions, litter production, leaf and litterfall chemistry, nutrient flux to the forest floor, retranslocation rates, and nutrient use efficiency of mangroves in Jobos Bay, Puerto Rico. The fringe forest had a salinity gradient from the ocean (35‰) to a salt flat (100‰) and a basin (about 80‰). Red (Rhizophora mangle), white (...

  7. Forest insurance

    Science.gov (United States)

    Ellis T. Williams

    1949-01-01

    Standing timber is one of the few important kinds of property that are not generally covered by insurance. Studies made by the Forest Service and other agencies have indicated that the risks involved in the insurance of timber are not unduly great, provided they can be properly distributed. Such studies, however, have thus far failed to induce any notable development...

  8. Forest Imaging

    Science.gov (United States)

    1992-01-01

    NASA's Technology Applications Center, with other government and academic agencies, provided technology for improved resources management to the Cibola National Forest. Landsat satellite images enabled vegetation over a large area to be classified for purposes of timber analysis, wildlife habitat, range measurement and development of general vegetation maps.

  9. Annual runoff and evapotranspiration of forestlands and non-forestlands in selected basins of the Loess Plateau of China.

    Science.gov (United States)

    Yanhui Wang; Pengtao Yu; Karl-Heinz Feger; Xiaohua Wei; Ge Sun; et al

    2011-01-01

    Large-scale forestation has been undertaken over decades principally to control the serious soil erosion in the Loess Plateau of China. A quantitative assessment of the hydrological effects of forestation, especially on basin water yield, is critical for the sustainable forestry development within this dry region. In this study, we constructed the multi-annual water...

  10. A comunidade de peixes de um riacho de Floresta com Araucária, alto rio Iguaçu, sul do Brasil The fish community in an Araucaria Forest stream, upper Iguaçu River basin, southern Brazil

    Directory of Open Access Journals (Sweden)

    Vinicius Abilhoa

    2008-06-01

    Full Text Available Foram avaliadas a composição, a dieta, as táticas alimentares e ocupação espacial da ictiofauna em um pequeno riacho dentro de um remanescente de Floresta com Araucária. Seis espécies de peixes foram coletadas, pertencentes a três ordens e quatro famílias, totalizando 110 exemplares. No ambiente de corredeira foram coletados e observados apenas Trichomycterus castroi Pinna, 1992 and Trichomycterus davisi Haseman, 1911, enquanto que no ambiente de remanso foram observados e capturados exemplares de Astyanax aff. scabripinnis (sensu Eigenmann, 1921, Astyanax totae Haluch & Abilhoa, 2005, Trichomycterus castroi Pinna, 1992, T. davisi, Phalloceros caudimaculatus (Hensel, 1868 e Jenynsia eigenmanni Haseman, 1911. Dezoito itens alimentares de origem autóctone, seis de alóctone e três de origem incerta foram identificados e tiveram sua freqüência de ocorrência calculada. Uma grande quantidade de itens exclusivos foi registrada, todavia os insetos constituíram a base alimentar mais importante, principalmente na forma de fragmentos e estágios imaturos (larvas e pupas, o que permitiu inferências a respeito de sobreposição alimentar. As espécies registradas no riacho foram classificadas em quatro guildas tróficas e quatro grupos funcionais. As espécies estudadas são capazes de utilizar diversos recursos alimentares e microambientes, o que é favorecido provavelmente pelo seu pequeno porte. O remanescente florestal estudado exerce grande importância no fornecimento de alimento, hábitats e refúgios, fatores importantes para manutenção da biota aquática.The species composition, diet, feeding tactics, and spatial occupation of fishes in a headwater stream which flows within a remaining fragment of Araucaria Forest were studied. One hundred and ten fishes of six species were collected, members of three orders and four families. In riffle areas, only Trichomycterus castroi Pinna, 1992 and Trichomycterus davisi Haseman, 1911 were

  11. Landscape fragmentation, severe drought, and the new Amazon forest fire regime.

    Science.gov (United States)

    Alencar, Ane A; Brando, Paulo M; Asner, Gregory P; Putz, Francis E

    2015-09-01

    Changes in weather and land use are transforming the spatial and temporal characteristics of fire regimes in Amazonia, with important effects on the functioning of dense (i.e., closed-canopy), open-canopy, and transitional forests across the Basin. To quantify, document, and describe the characteristics and recent changes in forest fire regimes, we sampled 6 million ha of these three representative forests of the eastern and southern edges of the Amazon using 24 years (1983-2007) of satellite-derived annual forest fire scar maps and 16 years of monthly hot pixel information (1992-2007). Our results reveal that changes in forest fire regime properties differentially affected these three forest types in terms of area burned and fire scar size, frequency, and seasonality. During the study period, forest fires burned 15% (0.3 million ha), 44% (1 million ha), and 46% (0.6 million ha) of dense, open, and transitional forests, respectively. Total forest area burned and fire scar size tended to increase over time (even in years of average rainfall in open canopy and transitional forests). In dense forests, most of the temporal variability in fire regime properties was linked to El Nino Southern Oscillation (ENSO)-related droughts. Compared with dense forests, transitional and open forests experienced fires twice as frequently, with at least 20% of these forests' areas burning two or more times during the 24-year study period. Open and transitional forests also experienced higher deforestation rates than dense forests. During drier years, the end of the dry season was delayed by about a month, which resulted in larger burn scars and increases in overall area burned later in the season. These observations suggest that climate-mediated forest flammability is enhanced by landscape fragmentation caused by deforestation, as observed for open and transitional forests in the Eastern portion of the Amazon Basin.

  12. River basin administration

    Science.gov (United States)

    Management of international rivers and their basins is the focus of the Centre for Comparative Studies on (International) River Basin Administration, recently established at Delft University of Technology in the Netherlands. Water pollution, sludge, and conflicting interests in the use of water in upstream and downstream parts of a river basin will be addressed by studying groundwater and consumption of water in the whole catchment area of a river.Important aspects of river management are administrative and policy aspects. The Centre will focus on policy, law, planning, and organization, including transboundary cooperation, posing standards, integrated environmental planning on regional scale and environmental impact assessments.

  13. Combating Forest Corruption: the Forest Integrity Network

    NARCIS (Netherlands)

    Gupta, A.; Siebert, U.

    2004-01-01

    This article describes the strategies and activities of the Forest Integrity Network. One of the most important underlying causes of forest degradation is corruption and related illegal logging. The Forest Integrity Network is a timely new initiative to combat forest corruption. Its approach is to

  14. Forest ownership dynamics of southern forests

    Science.gov (United States)

    Brett J. Butler; David N. Wear

    2013-01-01

    Key FindingsPrivate landowners hold 86 percent of the forest area in the South; two-thirds of this area is owned by families or individuals.Fifty-nine percent of family forest owners own between 1 and 9 acres of forest land, but 60 percent of family-owned forests are in holdings of 100 acres or more.Two-...

  15. Road surface erosion on the Jackson Demonstration State Forest: results of a pilot study

    Science.gov (United States)

    Brian Barrett; Rosemary Kosaka; David. Tomberlin

    2012-01-01

    This paper presents results of a 3 year pilot study of surface erosion on forest roads in the Jackson Demonstration State Forest in California’s coastal redwood region. Ten road segments representing a range of surface, grade, and ditch conditions were selected for the study. At each segment, settling basins with tipping buckets were installed to measure...

  16. Evaluating multiple causes of persistent low microwave backscatter from Amazon forests after the 2005 drought

    Science.gov (United States)

    Steve Frolking; Stephen Hagen; Bobby Braswell; Tom Milliman; Christina Herrick; Seth Peterson; Dar Roberts; Michael Keller; Michael Palace; Krishna Prasad Vadrevu

    2017-01-01

    Amazonia has experienced large-scale regional droughts that affect forest productivity and biomass stocks. Space-borne remote sensing provides basin-wide data on impacts of meteorological anomalies, an important complement to relatively limited ground observations across the Amazon’s vast and remote humid tropical forests. Morning overpass QuikScat Ku-band microwave...

  17. State of Conservation of the Native Forests in Entre Ríos (Argentina) and Changes in Land Use

    Science.gov (United States)

    Sabattini, R. A.; Sione, S. M.; Ledesma, S. G.; Sabattini, J. A.; Wilson, M. G.

    2012-04-01

    The native forest area of Entre Ríos province (Argentina) is associated with a constant change in land use, with an increase in recent years in agricultural use, especially for soybean crop. In addition, since its inadequate management has triggered degradation processes of the natural forest structure, the implementation of strategies for the restoration and conservation of native forests has become a priority. The aim of this study was to diagnose the conservation state of the native forest in the basin of the Estacas Stream (Entre Ríos, Argentina) after the change in land use, to help design guidelines for the restoration and sustainable management of these ecosystems. The field study was conducted in October 2010, in a representative area of the native forest of 73,000 ha. Using Landsat 5-TM images (INPE), environments were separated by manual vectorization, identifying and classifying native forests and other lands (agricultural, urban). Using a field exploratory survey (58 geo-referenced sampling points), we developed patterns corresponding to the different types of forests, contrasting this information with the digital data of the images. The native forests were classified according to type (high/low forest, open/closed forest, savanna), successional stage (climax, successional or regeneration forest) and degree of disturbance (weed growth, erosion, fire), and their frequency determined. Each classification was assessed by a contingency matrix, and global reliability index and the Kappa index. The information obtained generated a classification map of native forests in the basin scale. We found that the native forest covered an area of 42,726.91 ha, accounting for 58.52% of the total basin area, and that the rest corresponded to other land uses. The most frequent native forests (59.09%) were climax forest, but accounted for only 8.2% of the basin area. Within this group, the most important were the low and open forest, with Prosopis affinis and Prosopis

  18. L'Afrique centrale: entre traditions et transitions. La mutation des socio-écosystèmes en Afrique centrale

    OpenAIRE

    Gillet, Pauline

    2016-01-01

    The forests of the Congo Basin are among the best preserved areas on Earth. Nevertheless, the factors causing deforestation around the world are also present in this subregion. The forest transition theory describes how the trend of forest areas decline at national level may precede an increase in these areas. If the effects of the forest transition are well known in terms of forest cover degradation, little is known about the effects of forest transition on socio-ecosystems (SES) (understood...

  19. Watershed Planning Basins

    Data.gov (United States)

    Vermont Center for Geographic Information — The Watershed Planning Basin layer is part of a larger dataset contains administrative boundaries for Vermont's Agency of Natural Resources. The dataset includes...

  20. BASINS Framework and Features

    Science.gov (United States)

    BASINS enables users to efficiently access nationwide environmental databases and local user-specified datasets, apply assessment and planning tools, and run a variety of proven nonpoint loading and water quality models within a single GIS format.

  1. K Basin Hazard Analysis

    International Nuclear Information System (INIS)

    PECH, S.H.

    2000-01-01

    This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Final Safety Analysis Report. This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report

  2. K Basin Hazard Analysis

    Energy Technology Data Exchange (ETDEWEB)

    PECH, S.H.

    2000-08-23

    This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Final Safety Analysis Report. This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report.

  3. K Basins Hazard Analysis

    International Nuclear Information System (INIS)

    WEBB, R.H.

    1999-01-01

    This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Safety Analysis Report (HNF-SD-WM-SAR-062/Rev.4). This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report

  4. Evaluation of Adsorption Capacity of Low Cost Adsorbent for the Removal of Congo Red Dye from Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Dattatraya Jirekar

    2016-10-01

    Full Text Available Vigna unguiculata seed husk powder has been investigated as low cost adsorbent for the removal of hazardous chemicals like Congo Red (CR dye from aqueous solution. Various parameters such as effect of contact time, initial CR dye concentration, adsorbent dose, effect of pH, zero-point pH were studied. Batch adsorption technique was employed to optimize the process parameter. The result indicated that, the percentage adsorption of Congo Red increased with increase in contact time, dose of adsorbent and initial concentration of Congo Red and decreased with addition of salt. The adsorption of Congo Red was 78% at the optimum pH of 6. Adsorption equilibrium was found to be reached in 24 h for 5 to 25 g/50 mL Congo red concentrations. The Langmuir and Freundlich isotherm models were found to provide an excellent fitting of the adsorption data.  The adsorption of CR follows Second order rate kinetics. Thermodynamic parameter (δGo showed that it was an exothermic process. This adsorbent was found to be effective and economically attractive. DOI: http://dx.doi.org/10.17807/orbital.v8i5.834

  5. Effect of pH, Dosage and Concentration on the Adsorption of Congo Red onto Untreated and Treated Aluminium Dross

    Science.gov (United States)

    Zakaria Mohamad Zulfika, Hazielim B.; Baini, Rubiyah; Zauzi, Nur Syuhada Ahmad

    2017-06-01

    The adsorption of congo red onto aluminium dross was studied in batch process. The objective of this study is to adsorption capacity between untreated and treated aluminium dross in the removal of congo red. Aluminium dross was leached with 250 ml of 1% of NaOH and and precipitated with 30% H2O2. The treated aluminium dross being calcined at 600°C for 3 hours. The surface area for untreated and treated aluminium dross was 10.06 m2/g and 79.80 m2/g respectively. Then the adsorption process was carried out on an orbital shaker at 200 rpm for 4 hours. In the effect of pH, it was found that untreated removes more congo red compared to the treated while in the effect of concentration solution and dosage of adsorbent, treated aluminium dross removes more congo red. In conclusion, this adsorbent was found to be effective and economically viable in the removal of congo red in waste water treatment.

  6. Un guide colonial. Le Guide du Voyageur au Congo belge et au Ruanda-Urundi A colonial guidebook. Travel guide to Belgian Congo and Ruanda-Urundi

    Directory of Open Access Journals (Sweden)

    Henri Nicolaï

    2013-03-01

    Full Text Available Le Guide, qui a connu cinq éditions pendant les dix dernières années du Congo belge, est un archétype du guide colonial. L’article rappelle d’abord la naissance du tourisme en Afrique centrale et ses caractéristiques. Fasciné longtemps par les mythes des Monts de la Lune et des sources du Nil, le tourisme congolais est, au départ, essentiellement élitiste, orienté surtout vers la grande chasse sportive. Gorilles de montagne, ascensions du Ruwenzori, danseurs Tutsi, Parc National Albert, pêcheurs wagenia deviennent les icônes d’un tourisme attiré en ordre principal par le Kivu, les Grands Lacs, Stanleyville et secondairement le Katanga. Le premier guide, édité par Vicicongo, en 1934, s’intitule d’ailleurs Congo-Nil. Tous ces mythes et ces décors se retrouvent dans quelques grands films américains d’aventure du début des années 50.L’article décrit ensuite la genèse du Guide, ses caractéristiques générales, son plan, son contenu. Beaucoup d’informations générales, pas de véritables circuits mais plutôt des itinéraires routiers. Produit par les services officiels d’information de la Colonie, le Guide a, parmi ses objectifs, de montrer la persistance et les résultats de l’action civilisatrice de la Belgique. Il affirme que le Congo n’est pas un pays d’art ni d’histoire et accorde donc une part prépondérante au milieu naturel. Il fournit une image tronquée de son histoire et exprime sur ses habitants les préjugés de l’époque.L’article se termine par quelques réflexions sur les tentatives d’un reporter d’une chaîne de télévision et d’un photographe d’utiliser le Guide de 1958 pour parcourir le pays un demi-siècle plus tard.The Travel Guide to Belgian Congo and Ruanda-Urundi, of which five editions were released during the last ten years of Belgian Congo, is an archetypal colonial guide.The paper first highlights the emergence and the features of tourism in Central Africa

  7. Forest fires

    International Nuclear Information System (INIS)

    Fuller, M.

    1991-01-01

    This book examines the many complex and sensitive issues relating to wildland fires. Beginning with an overview of the fires of 1980s, the book discusses the implications of continued drought and considers the behavior of wildland fires, from ignition and spread to spotting and firestorms. Topics include the effects of weather, forest fuels, fire ecology, and the effects of fire on plants and animals. In addition, the book examines firefighting methods and equipment, including new minimum impact techniques and compressed air foam; prescribed burning; and steps that can be taken to protect individuals and human structures. A history of forest fire policies in the U.S. and a discussion of solutions to fire problems around the world completes the coverage. With one percent of the earth's surface burning every year in the last decade, this is a penetrating book on a subject of undeniable importance

  8. A legacy of low-impact logging does not elevate prevalence of potentially pathogenic protozoa in free-ranging gorillas and chimpanzees in the Republic of Congo: logging and parasitism in African apes.

    Science.gov (United States)

    Gillespie, Thomas R; Morgan, David; Deutsch, J Charlie; Kuhlenschmidt, Mark S; Salzer, Johanna S; Cameron, Kenneth; Reed, Trish; Sanz, Crickette

    2009-12-01

    Many studies have examined the long-term effects of selective logging on the abundance and diversity of free-ranging primates. Logging is known to reduce the abundance of some primate species through associated hunting and the loss of food trees for frugivores; however, the potential role of pathogens in such primate population declines is largely unexplored. Selective logging results in a suite of alterations in host ecology and forest structure that may alter pathogen dynamics in resident wildlife populations. In addition, environmental pollution with human fecal material may present a risk for wildlife infections with zoonotic protozoa, such as Cryptosporidium and Giardia. To better understand this interplay, we compared patterns of infection with these potentially pathogenic protozoa in sympatric western lowland gorillas (Gorilla gorilla gorilla) and chimpanzees (Pan troglodytes troglodytes) in the undisturbed Goualougo Triangle of Nouabalé-Ndoki National Park and the adjacent previously logged Kabo Concession in northern Republic of Congo. No Cryptosporidium infections were detected in any of the apes examined and prevalence of infection with Giardia was low (3.73% overall) and did not differ between logged and undisturbed forest for chimpanzees or gorillas. These results provide a baseline for prevalence of these protozoa in forest-dwelling African apes and suggest that low-intensity logging may not result in long-term elevated prevalence of potentially pathogenic protozoa.

  9. Interactions of Forests, Climate, Water Resources, and Humans in a Changing Environment: Research Needs

    OpenAIRE

    Sun, Ge; Segura, Catalina

    2013-01-01

    The aim of the special issue “Interactions of Forests, Climate, Water Resources, and Humans in a Changing Environment” is to present case studies on the influences of natural and human disturbances on forest water resources under a changing climate. Studies in this collection of six papers cover a wide range of geographic regions from Australia to Nigeria with spatial research scale spanning from a tree leaf, to a segment of forest road, and large basins with mixed land uses. T...

  10. Dispersal of forest insects

    Science.gov (United States)

    Mcmanus, M. L.

    1979-01-01

    Dispersal flights of selected species of forest insects which are associated with periodic outbreaks of pests that occur over large contiguous forested areas are discussed. Gypsy moths, spruce budworms, and forest tent caterpillars were studied for their massive migrations in forested areas. Results indicate that large dispersals into forested areas are due to the females, except in the case of the gypsy moth.

  11. South Dakota's forests 2005

    Science.gov (United States)

    Ronald J. Piva; W. Keith Moser; Douglas D. Haugan; Gregory J. Josten; Gary J. Brand; Brett J. Butler; Susan J. Crocker; Mark H. Hansen; Dacia M. Meneguzzo; Charles H. Perry; Christopher W. Woodall

    2009-01-01

    The first completed annual inventory of South Dakota's forests reports almost 1.7 million acres of forest land. Softwood forests make up 74 percent of the total forest land area; the ponderosa pine forest type by itself accounts for 69 percent of the total.

  12. Forest report 2016

    International Nuclear Information System (INIS)

    2016-01-01

    This forest condition report of Hesse (Germany) includes the following topics: forest condition survey for all tree species, forest in the in the Rhine-Main area, weather and climate, soil water balance and drought stress, insects and fungi, Forestry Environment Monitoring, infiltrated substances, main results of Forest soil survey in Hesse (BZE II), the substrate group red sandstone, heavy metal contamination of forests.

  13. Mapping Forest Inventory and Analysis forest land use: timberland, reserved forest land, and other forest land

    Science.gov (United States)

    Mark D. Nelson; John Vissage

    2007-01-01

    The Forest Inventory and Analysis (FIA) program produces area estimates of forest land use within three subcategories: timberland, reserved forest land, and other forest land. Mapping these subcategories of forest land requires the ability to spatially distinguish productive from unproductive land, and reserved from nonreserved land. FIA field data were spatially...

  14. Forests and Forest Cover - MDC_NaturalForestCommunity

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — A point feature class of NFCs - Natural Forest Communities. Natural Forest Community shall mean all stands of trees (including their associated understory) which...

  15. Eco-hydrological Responses to Soil and Water Conservation in the Jinghe River Basin

    Science.gov (United States)

    Peng, H.; Jia, Y.; Qiu, Y.

    2011-12-01

    The Jinghe River Basin is one of the most serious soil erosion areas in the Loess Plateau. Many measures of soil and water conservation were applied in the basin. Terrestrial ecosystem model BIOME-BGC and distributed hydrological model WEP-L were used to build eco-hydrological model and verified by field observation and literature values. The model was applied in the Jinghe River Basin to analyze eco-hydrological responses under the scenarios of vegetation type change due to soil and water conservation polices. Four scenarios were set under the measures of conversion of cropland to forest, forestation on bare land, forestation on slope wasteland and planting grass on bare land. Analysis results show that the soil and water conservation has significant effects on runoff and the carbon cycle in the Jinghe River Basin: the average annual runoff would decrease and the average annual NPP and carbon storage would increase. Key words: soil and water conservation; conversion of cropland to forest; eco-hydrology response; the Jinghe River Basin

  16. Quantifying flooding regime in floodplain forests to guide river restoration

    Science.gov (United States)

    Christian O. Marks; Keith H. Nislow; Francis J. Magilligan

    2014-01-01

    Determining the flooding regime needed to support distinctive floodplain forests is essential for effective river conservation under the ubiquitous human alteration of river flows characteristic of the Anthropocene Era. At over 100 sites throughout the Connecticut River basin, the largest river system in New England, we characterized species composition, valley and...

  17. Different origin and dispersal of sulfadoxine-resistant Plasmodium falciparum haplotypes between Eastern Africa and Democratic Republic of Congo

    DEFF Research Database (Denmark)

    Baraka, Vito; Delgado-Ratto, Christopher; Nag, Sidsel

    2017-01-01

    Sulfadoxine/pyrimethamine (SP) is still used for malaria control in sub-Saharan Africa; however, widespread resistance is a major concern. This study aimed to determine the dispersal and origin of sulfadoxine resistance lineages in the Democratic Republic of the Congo compared with East African.......3 and 7.7 kb) flanking the Pfdhps gene were assayed. Evolutionary analysis revealed a shared origin of Pfdhps haplotypes in East Africa, with a distinct population clustering in DR Congo. Furthermore, in Tanzania there was an independent distinct origin of Pfdhps SGEGA resistant haplotype. In Uganda...... and Tanzania, gene flow patterns contribute to the dispersal and shared origin of parasites carrying double- and triple-mutant Pfdhps haplotypes associated with poor outcomes of intermittent preventive treatment during pregnancy using SP (IPTp-SP). However, the origins of the Pfdhps haplotypes in DR Congo...

  18. Study of risk of pollution by the heavy metals of the water and fishes of the Congo river

    International Nuclear Information System (INIS)

    Tuakashikila, M.; Mbuyi, K.M.; Kabwe, C.; Malumba, M.; Kapembo, L.; Lusamba, N.; Lundemba, S.; Barutti, Y.

    2010-01-01

    In order to conduct property this study, we have chosen to evaluate cadmium and lead concentration in Congo River water and un three species of fishes (Oreochromis niloticus nilotucus, Schilbe mystus and Campylomormyrus). These fishes have been collected from three sites in Congo River during the time from August to November 2009. Sample analysis (water and fishes) revealed that cadmium and concentration were lower then world heath organization (Who) acceptable standards. The campulomormyrus species present the highest lead concentration of all studied species and further mose this concentration has been found in Kinsuka. This could be justified by the position Kinsuka site which is the down stream section compared to Kinkole and Maluku position in Congo River. Therefor harmful effects are not expected in short time, however they are dangerous in long time because these metals are both toxic and cumulative, may damage concerned organs

  19. Hobbes y el Congo: marcos, violencia local e intervención internacional | Hobbes and the Congo: Frames,Local Violence, and International Intervention

    Directory of Open Access Journals (Sweden)

    Séverine AUTESSERRE

    2011-02-01

    Full Text Available ¿Por qué los constructores internacionales de la paz no toman en consideración las causas locales de los procesos de paz que fallan? A través del presente artículo demuestro cómo las agendas locales jugaron entonces un rol decisivo en fomentar la violencia a nivel local, regional y nacional. Sin embargo, la existencia de un marco de construcción de la paz posbélica configuraba la visión internacional de la violencia y de la intervención de tal manera que la resolución del conflicto local era considerada como irrelevante e ilegitima. Este marco incluyó enseguida cuatro elementos fundamentales: los actores internacionales etiquetaron la situación en Congo de “postconflicto”; estos mismos actores creyeron que la violencia constituía un componente innato en la sociedad congolesa y, por lo tanto, aceptable incluso en tiempos de paz; conceptualizaron la intervención internacional como un asunto exclusivo de la esferas nacional e internacional; y consideraron la celebración de elecciones, en lugar de la resolución del conflicto local, como una herramienta viable, apropiada y efectiva para la construcción del estado y de la paz. Este marco, al autorizar y justificar prácticas y políticas específicas mientras impedía otras, en particular la resolución de conflictos locales, acabó condenando en última instancia los esfuerzos para la construcción de la paz. Para concluir, sostengo que el análisis de los marcos discursivos es un enfoque fructífero para intentar resolver los puzles de los fracasos internacionales en la construcción de la paz que se dan, también, más allá de las fronteras del Congo.Why do international peacebuilders fail to address the local causes of peace process failures? In this article,I demonstrate that local agendas played a decisive role in sustaining local, national, and regional violence. However, a postcon?ict peacebuilding frame shaped the international understanding of violence and intervention

  20. dwindling ethiopian forests

    African Journals Online (AJOL)

    eliasn

    1999-05-26

    May 26, 1999 ... Shelter for animals: Forests are natural “habitats for many wild animals. .... nificance of forest conservation and development in Ethiopia's combat ...... of forests are not, unfortunately, analogues to traffic lights where the impact.

  1. Tenure and forest income

    DEFF Research Database (Denmark)

    Jagger, Pamela; Luckert, Martin K.; Duchelle, Amy E.

    2014-01-01

    We explore the relationship between tenure and forest income in 271 villages throughout the tropics. We find that state-owned forests generate more forest income than private and community-owned forests both per household and per hectare. We explore whether forest income varies according...... to the extent of rule enforcement, and congruence (i.e., overlap of user rights between owners and users). We find negative associations between enforcement and smallholder forest income for state-owned and community forests, and positive associations for privately owned forests. Where user rights are limited...... to formal owners we find negative associations for state-owned forests. Overlapping user rights are positively associated with forest income for community forests. Our findings suggest that policy reforms emphasizing enforcement and reducing overlapping claims to forest resources should consider possible...

  2. Restoration of biogeochemical function in mangrove forests

    Science.gov (United States)

    McKee, K.L.; Faulkner, P.L.

    2000-01-01

    Forest structure of mangrove restoration sites (6 and 14 years old) at two locations (Henderson Creek [HC] and Windstar [WS]) in southwest Florida differed from that of mixed-basin forests (>50 years old) with which they were once contiguous. However, the younger site (HC) was typical of natural, developing forests, whereas the older site (WS) was less well developed with low structural complexity. More stressful physicochemical conditions resulting from incomplete tidal flushing (elevated salinity) and variable topography (waterlogging) apparently affected plant survival and growth at the WS restoration site. Lower leaf fall and root production rates at the WS restoration site, compared with that at HC were partly attributable to differences in hydroedaphic conditions and structural development. However, leaf and root inputs at each restoration site were not significantly different from that in reference forests within the same physiographic setting. Macrofaunal consumption of tethered leaves also did not differ with site history, but was dramatically higher at HC compared with WS, reflecting local variation in leaf litter processing rates, primarily by snails (Melampus coffeus). Degradation of leaves and roots in mesh bags was slow overall at restoration sites, however, particularly at WS where aerobic decomposition may have been more limited. These findings indicate that local or regional factors such as salinity regime act together with site history to control primary production and turnover rates of organic matter in restoration sites. Species differences in senescent leaf nitrogen content and degradation rates further suggest that restoration sites dominated by Laguncularia racemosa and Rhizophora mangle should exhibit slower recycling of nutrients compared with natural basin forests where Avicennia germinans is more abundant. Structural development and biogeochemical functioning of restored mangrove forests thus depend on a number of factors, but site

  3. Predicting hydrological response to forest changes by simple statistical models: the selection of the best indicator of forest changes with a hydrological perspective

    Science.gov (United States)

    Ning, D.; Zhang, M.; Ren, S.; Hou, Y.; Yu, L.; Meng, Z.

    2017-01-01

    Forest plays an important role in hydrological cycle, and forest changes will inevitably affect runoff across multiple spatial scales. The selection of a suitable indicator for forest changes is essential for predicting forest-related hydrological response. This study used the Meijiang River, one of the headwaters of the Poyang Lake as an example to identify the best indicator of forest changes for predicting forest change-induced hydrological responses. Correlation analysis was conducted first to detect the relationships between monthly runoff and its predictive variables including antecedent monthly precipitation and indicators for forest changes (forest coverage, vegetation indices including EVI, NDVI, and NDWI), and by use of the identified predictive variables that were most correlated with monthly runoff, multiple linear regression models were then developed. The model with best performance identified in this study included two independent variables -antecedent monthly precipitation and NDWI. It indicates that NDWI is the best indicator of forest change in hydrological prediction while forest coverage, the most commonly used indicator of forest change is insignificantly related to monthly runoff. This highlights the use of vegetation index such as NDWI to indicate forest changes in hydrological studies. This study will provide us with an efficient way to quantify the hydrological impact of large-scale forest changes in the Meijiang River watershed, which is crucial for downstream water resource management and ecological protection in the Poyang Lake basin.

  4. Indiana's Forests 2008

    Science.gov (United States)

    Christopher W. Woodall; Mark N. Webb; Barry T. Wilson; Jeff Settle; Ron J. Piva; Charles H. Perry; Dacia M. Meneguzzo; Susan J. Crocker; Brett J. Butler; Mark Hansen; Mark Hatfield; Gary Brand; Charles. Barnett

    2011-01-01

    The second full annual inventory of Indiana's forests reports more than 4.75 million acres of forest land with an average volume of more than 2,000 cubic feet per acre. Forest land is dominated by the white oak/red oak/hickory forest type, which occupies nearly a third of the total forest land area. Seventy-six percent of forest land consists of sawtimber, 16...

  5. Primates in peril: the significance of Brazil, Madagascar, Indonesia and the Democratic Republic of the Congo for global primate conservation

    Science.gov (United States)

    Mittermeier, Russell A.; Wich, Serge; Gouveia, Sidney; Dobrovolski, Ricardo; Nijman, Vincent; Rylands, Anthony B.; Johnson, Steig; Rodrigues de Melo, Fabiano; Schwitzer, Christoph; Roos, Christian; Cheyne, Susan M.; Martins Kierulff, Maria Cecilia; Raharivololona, Brigitte; Ratsimbazafy, Jonah; Supriatna, Jatna; Boonratana, Ramesh; Wedana, Made; Setiawan, Arif

    2018-01-01

    Primates occur in 90 countries, but four—Brazil, Madagascar, Indonesia, and the Democratic Republic of the Congo (DRC)—harbor 65% of the world’s primate species (439) and 60% of these primates are Threatened, Endangered, or Critically Endangered (IUCN Red List of Threatened Species 2017-3). Considering their importance for global primate conservation, we examine the anthropogenic pressures each country is facing that place their primate populations at risk. Habitat loss and fragmentation are main threats to primates in Brazil, Madagascar, and Indonesia. However, in DRC hunting for the commercial bushmeat trade is the primary threat. Encroachment on primate habitats driven by local and global market demands for food and non-food commodities hunting, illegal trade, the proliferation of invasive species, and human and domestic-animal borne infectious diseases cause habitat loss, population declines, and extirpation. Modeling agricultural expansion in the 21st century for the four countries under a worst-case-scenario, showed a primate range contraction of 78% for Brazil, 72% for Indonesia, 62% for Madagascar, and 32% for DRC. These pressures unfold in the context of expanding human populations with low levels of development. Weak governance across these four countries may limit effective primate conservation planning. We examine landscape and local approaches to effective primate conservation policies and assess the distribution of protected areas and primates in each country. Primates in Brazil and Madagascar have 38% of their range inside protected areas, 17% in Indonesia and 14% in DRC, suggesting that the great majority of primate populations remain vulnerable. We list the key challenges faced by the four countries to avert primate extinctions now and in the future. In the short term, effective law enforcement to stop illegal hunting and illegal forest destruction is absolutely key. Long-term success can only be achieved by focusing local and global public

  6. Patterns of sexual violence in Eastern Democratic Republic of Congo: reports from survivors presenting to Panzi Hospital in 2006

    Science.gov (United States)

    2010-01-01

    Background Despite the signing of international peace agreements, a deadly war continues in the Democratic Republic of Congo (DRC) and sexual violence is a prominent modus operandi of many military groups operating in the region. Methods Retrospective cohort study of women who presented to Panzi Hospital in 2006 requesting post-sexual violence care. Data was extracted and analyzed to describe the patterns of sexual violence. Results A total of 1,021 medical records were reviewed. A majority of attacks occurred in individual homes (56.5%), with the fields (18.4%) and the forest (14.3%) also being frequent locations of attack. In total, 58.9% of all attacks occurred at night. Of the four primary types of sexual violence, gang rape predominated (59.3%) and rape Not Otherwise Specified (NOS) was also common (21.5%). Sexual slavery was described by 4.9% of the survivors and a combination of gang rape and sexual slavery was described by 11.7%. The mean number of assailants per attack was 2.5 with a range of one to > 15. There were several demographic predictors for sexual slavery. Controlling for age, education level and occupation, a marital status of "single" increased the risk of sexual slavery (OR = 2.97, 95% CI = 1.12-7.85). Similarly, after controlling for other variables, age was a significant predictor of sexual slavery with older women being at a slightly reduced risk (OR = 0.96, 95% CI = 0.92-0.99). Women who experienced sexual slavery were 37 times more likely to have a resultant pregnancy in comparison to those who reported other types of sexual violence (OR = 37.50, 95% CI = 14.57-99.33). Conclusions Among sexual violence survivors presenting to Panzi Hospital in 2006, the majority of attacks occurred in women's own homes, often at night. This represents a pattern of violence that differs from other conflict settings and has important implications regarding protection strategies. Sexual violence in South Kivu was also marked with a predominance of gang rape

  7. Patterns of sexual violence in Eastern Democratic Republic of Congo: reports from survivors presenting to Panzi Hospital in 2006

    Directory of Open Access Journals (Sweden)

    Lipton Robert I

    2010-05-01

    Full Text Available Abstract Background Despite the signing of international peace agreements, a deadly war continues in the Democratic Republic of Congo (DRC and sexual violence is a prominent modus operandi of many military groups operating in the region. Methods Retrospective cohort study of women who presented to Panzi Hospital in 2006 requesting post-sexual violence care. Data was extracted and analyzed to describe the patterns of sexual violence. Results A total of 1,021 medical records were reviewed. A majority of attacks occurred in individual homes (56.5%, with the fields (18.4% and the forest (14.3% also being frequent locations of attack. In total, 58.9% of all attacks occurred at night. Of the four primary types of sexual violence, gang rape predominated (59.3% and rape Not Otherwise Specified (NOS was also common (21.5%. Sexual slavery was described by 4.9% of the survivors and a combination of gang rape and sexual slavery was described by 11.7%. The mean number of assailants per attack was 2.5 with a range of one to > 15. There were several demographic predictors for sexual slavery. Controlling for age, education level and occupation, a marital status of "single" increased the risk of sexual slavery (OR = 2.97, 95% CI = 1.12-7.85. Similarly, after controlling for other variables, age was a significant predictor of sexual slavery with older women being at a slightly reduced risk (OR = 0.96, 95% CI = 0.92-0.99. Women who experienced sexual slavery were 37 times more likely to have a resultant pregnancy in comparison to those who reported other types of sexual violence (OR = 37.50, 95% CI = 14.57-99.33. Conclusions Among sexual violence survivors presenting to Panzi Hospital in 2006, the majority of attacks occurred in women's own homes, often at night. This represents a pattern of violence that differs from other conflict settings and has important implications regarding protection strategies. Sexual violence in South Kivu was also marked with a

  8. Primates in peril: the significance of Brazil, Madagascar, Indonesia and the Democratic Republic of the Congo for global primate conservation.

    Science.gov (United States)

    Estrada, Alejandro; Garber, Paul A; Mittermeier, Russell A; Wich, Serge; Gouveia, Sidney; Dobrovolski, Ricardo; Nekaris, K A I; Nijman, Vincent; Rylands, Anthony B; Maisels, Fiona; Williamson, Elizabeth A; Bicca-Marques, Julio; Fuentes, Agustin; Jerusalinsky, Leandro; Johnson, Steig; Rodrigues de Melo, Fabiano; Oliveira, Leonardo; Schwitzer, Christoph; Roos, Christian; Cheyne, Susan M; Martins Kierulff, Maria Cecilia; Raharivololona, Brigitte; Talebi, Mauricio; Ratsimbazafy, Jonah; Supriatna, Jatna; Boonratana, Ramesh; Wedana, Made; Setiawan, Arif

    2018-01-01

    Primates occur in 90 countries, but four-Brazil, Madagascar, Indonesia, and the Democratic Republic of the Congo (DRC)-harbor 65% of the world's primate species (439) and 60% of these primates are Threatened, Endangered, or Critically Endangered (IUCN Red List of Threatened Species 2017-3). Considering their importance for global primate conservation, we examine the anthropogenic pressures each country is facing that place their primate populations at risk. Habitat loss and fragmentation are main threats to primates in Brazil, Madagascar, and Indonesia. However, in DRC hunting for the commercial bushmeat trade is the primary threat. Encroachment on primate habitats driven by local and global market demands for food and non-food commodities hunting, illegal trade, the proliferation of invasive species, and human and domestic-animal borne infectious diseases cause habitat loss, population declines, and extirpation. Modeling agricultural expansion in the 21st century for the four countries under a worst-case-scenario, showed a primate range contraction of 78% for Brazil, 72% for Indonesia, 62% for Madagascar, and 32% for DRC. These pressures unfold in the context of expanding human populations with low levels of development. Weak governance across these four countries may limit effective primate conservation planning. We examine landscape and local approaches to effective primate conservation policies and assess the distribution of protected areas and primates in each country. Primates in Brazil and Madagascar have 38% of their range inside protected areas, 17% in Indonesia and 14% in DRC, suggesting that the great majority of primate populations remain vulnerable. We list the key challenges faced by the four countries to avert primate extinctions now and in the future. In the short term, effective law enforcement to stop illegal hunting and illegal forest destruction is absolutely key. Long-term success can only be achieved by focusing local and global public

  9. Antiretroviral treatment program retention among HIV-infected children in the Democratic Republic of Congo.

    Directory of Open Access Journals (Sweden)

    John Ditekemena

    Full Text Available BACKGROUND: Retaining patients with HIV infection in care is still a major challenge in sub- Saharan Africa, particularly in the Democratic Republic of Congo (DRC where the antiretroviral treatment (ART coverage is low. Monitoring retention is an important tool for evaluating the quality of care. METHODS AND FINDINGS: A review of medical records of HIV-infected children was performed in three health facilities in the DRC: the Amo-Congo Health center, the Monkole Clinic in Kinshasa, and the HEAL Africa Clinic in Goma. Medical records of 720 children were included. Kaplan Meier curves were constructed with the probability of retention at 6 months, 1 year, 2 years and 3 years. Retention rates were: 88.2% (95% CI: 85.1%-90.8% at 6 months; 85% (95% CI: 81.5%-87.6% at one year; 79.4% (95%CI: 75.5%-82.8% at two years and 74.7% (95% CI: 70.5%-78.5% at 3 years. The retention varied across study sites: 88.2%, 66.6% and 92.5% at 6 months; 84%, 59% and 90% at 12 months and 75.7%, 56.3% and 85.8% at 24 months respectively for Amo-Congo/Kasavubu, Monkole facility and HEAL Africa. After multivariable Cox regression four variables remained independently associated with attrition: study site, CD4 cell count <350 cells/µL, children younger than 2 years and children whose caregivers were member of an independent church. CONCLUSIONS: Attrition remains a challenge for pediatric HIV positive patients in ART programs in DRC. In addition, the low coverage of pediatric treatment exacerbates the situation of pediatric HIV/AIDS.

  10. [Exploratory study of road safety in Brazzaville and Pointe-Noire in Republic of the Congo].

    Science.gov (United States)

    Batala Mpondo, Georges; Bouanga, Marianne; Saya, Yvette Marie Clarisse; Maurice, Pierre; Burigusa, Guillaume

    2014-01-01

    Although road accidents in the Congo are reaching alarming levels (2,720 accidents in 2010 and 3,126 accidents in 2011), especially with the massive arrival of "Jakarta" mopeds, no evaluation has been conducted to identify and understand the factors responsible for this problem. This article reports the results of an exploratory study conducted in Brazzaville and Pointe-Noire based on information collected from existing documents and by semidirective questionnaire of people from various sectors able to elucidate the problem of road safety. Using William Haddon's matrix, the parameters investigated were : road user behaviour ; environmental and technological factors ; characteristics of road accident victims ; quality of care ; intervention times and organization of prevention. This study demonstrated the absence of a road safety policy in Congo. It also showed that the main factors responsible for road accidents are behavioural (failure to wear safety belts, failure to comply with road signs, fatigue, use of a telephone while driving, etc.), followed by environmental and technological factors (insufficient traffic lights, absence of sidewalks, disorganized occupation of roads, general state of vehicles). This study shows that, in order to improve road safety in the Congo, it is essential to promote the development of national road safety policies and an action plan, intervention on the determinants of road accidents, and a change of road user behaviours (compulsory use of safety belts, ban on the use of a telephone and smoking while driving, etc.). Effective organization of the management of road accident victims and allocation of a budget to implement a road safety policy are also necessary.

  11. Geochemistry and geochronology of the Archean and palaeo-Proterozoic formations of southern Cameroon (Ntem group, Congo craton)

    International Nuclear Information System (INIS)

    Rchameni, R.

    1997-01-01

    The aim of this work is to understand the crustal evolution of the NW margin of the Congo craton using structural, petrography, isotopic, geochemical and geochronological studies of the Archean and palaeo-Proterozoic formations of the Ntem group of southern Cameroon. The synthesis of these studies allows to propose a diapir-type gravity model linked with the genesis of granitoids to explain the geodynamical evolution of this part of the craton during the Archean. A convergence model with the collision of the Congo and Sao-Francisco cratons and with crust thickening followed by a relaxation phase is proposed for the palaeo-Proterozoic. (J.S.)

  12. Relative Abundance and Diversity of Bacterial Methanotrophs at the Oxic?Anoxic Interface of the Congo Deep-Sea Fan

    OpenAIRE

    Bessette, Sandrine; Moalic, Yann; Gautey, S?bastien; Lesongeur, Fran?oise; Godfroy, Anne; Toffin, Laurent

    2017-01-01

    Sitting at ∼5,000 m water depth on the Congo-Angola margin and ∼760 km offshore of the West African coast, the recent lobe complex of the Congo deep-sea fan receives large amounts of fluvial sediments (3–5% organic carbon). This organic-rich sedimentation area harbors habitats with chemosynthetic communities similar to those of cold seeps. In this study, we investigated relative abundance, diversity and distribution of aerobic methane-oxidizing bacteria (MOB) communities at the oxic–anoxic in...

  13. Etude bactériologique et biochimique du miel vendu au marché central de Bukavu (Congo

    Directory of Open Access Journals (Sweden)

    Kitambala, K.

    1999-01-01

    Full Text Available Bacteriological and Biochemical Study of Honey Sold at Bukavu (Congo Central Market. The honey sold in the central market of Bukavu (Congo is produced by traditional bee keepers. This article deals with a bacteriological and biochemical study of this product in order to determine its contamination and pollution levels. Results indicated a contamination of faecal origin (presence of enterobacteria such as Escherichia coli. The bacteriological tests showed the presence of bacteria fermenting glucose, thus altering the quality of the honey. The latter is therefore inappropriate for consumption and constitutes a danger for the health of humans.

  14. Hydrological and Meteorological Role of Forests: Implications for the Regulation of Water and Energy Balances

    Science.gov (United States)

    Salazar, J. F.; Villegas, J. C.; Bettin, D. M.; Molina, R.; Henao, J. J.; Rodríguez, E.; Rendón, A.; Hoyos, I.; Poveda, G.

    2016-12-01

    In last decades, there has been increasing debate about the hydrological and meteorological role of forests, particularly regarding its role in the regulation of the energy and water balances. Here we summarize results from an ongoing research program studying this problem. First, we introduce the notion of ecohydrological scaling to show the existence of two alternative states of regulated or unregulated streamflows in the main tributaries of the Amazon river basin. The transition between both states is associated with the loss of forest cover, with a potential critical threshold at around 40% forest loss in the Amazon. These results imply that large-scale forest loss can force the entire Amazon basin system beyond a critical threshold where its natural streamflow regulation is lost. More generally, our proposed framework provides insights for a physical interpretation of the scaling relations in river basins, as well as foundations and tools to develop early warnings of critical transitions in river basins. Second, we show that long-term rainfall-streamflow ratios converge to low values with low spatial variability in forested basins of the world, independent of location, climatic regime, basin size or forest type. We interpret this as evidence that high forest cover provides long-term regulation of the water balance. Third, we examine the linkage between the presence of tropical forests in South America and the long-term spatial distribution of continental precipitation, and found evidence suggesting that the Amazon forests enhance the atmospheric rivers flowing inland from the Atlantic ocean, particularly during the austral and boreal summers. The associated effects on precipitation may be highly relevant for water availability in river basins located downstream such atmospheric rivers, such as the La Plata and the Orinoco river basins. Finally, we explore the linkage between forest-induced temperature inversions and the vertical transport of atmospheric

  15. Percent Forest Cover (Future)

    Data.gov (United States)

    U.S. Environmental Protection Agency — Forests provide economic and ecological value. High percentages of forest cover (FORPCTFuture) generally indicate healthier ecosystems and cleaner surface water....

  16. Percent Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — Forests provide economic and ecological value. High percentages of forest cover (FORPCT) generally indicate healthier ecosystems and cleaner surface water. More...

  17. Severe Crimean-Congo haemorrhagic fever presented with massive retroperitoneal haemorrhage that recovered without antiviral treatment

    DEFF Research Database (Denmark)

    Gharabaghi, Mehrnaz Asadi; Chinikar, Sadegh; Ghiasi, Seyyed Mojtaba

    2011-01-01

    Crimean-Congo haemorrhagic fever (CCHF) is a tickborne viral zoonosis with up to 50% mortality in humans caused by CCHF virus belonging to the genus Nairovirus, family Bunyaviridae. The geographical distribution of CCHF cases corresponds closely with the distribution of principle tick vectors...... that is species of Hyaloma. The disease presents with non-specific febrile symptoms, but progress to a serious haemorrhagic syndrome that, soon after, a full blown multi organ failure may develop with prominent features of liver damage and bleeding diathesis. The authors present a case of a 39-year-old man...

  18. Inspiration fuels space research in Congo. Combating malnutrition with Spirulina, the green protein source

    International Nuclear Information System (INIS)

    2016-01-01

    In Congo, around 43% of all children under the age of five suffer from chronic malnutrition. The result is a high infant mortality rate./ Researchers from the Belgian Nuclear research Center SCK•CEN started working on the cultivation of spirulina, a type of algae rich in vitamins and minerals that are essential for combating chronic malnutrition in children. This Inspiration project is the first in a series and signals the ambition of SCK•CEN to contribute towards a balanced and sustainable world.

  19. Isolation and whole-genome sequencing of a Crimean-Congo hemorrhagic fever virus strain, Greece.

    Science.gov (United States)

    Papa, Anna; Papadopoulou, Elpida; Tsioka, Katerina; Kontana, Anastasia; Pappa, Styliani; Melidou, Ageliki; Giadinis, Nektarios D

    2018-03-01

    Crimean-Congo hemorrhagic fever virus (CCHFV) was isolated from a pool of two adult Rhipicephalus bursa ticks removed from a goat in 2015 in Greece. The strain clusters into lineage Europe 2 representing the second available whole-genome sequenced isolate of this lineage. CCHFV IgG antibodies were detected in 8 of 19 goats of the farm. Currently CCHFV is not associated with disease in mammals other than humans. Studies in animal models are needed to investigate the pathogenicity level of lineage Europe 2 and compare it with that of other lineages. Copyright © 2018 Elsevier GmbH. All rights reserved.

  20. Crimean-Congo haemorrhagic fever virus infection in birds: field investigations in Senegal.

    Science.gov (United States)

    Zeller, H G; Cornet, J P; Camicas, J L

    1994-01-01

    In Senegal, wild ground-feeding birds are frequently infested with immature ticks. In two areas where numerous Crimean-Congo haemorrhagic fever (CCHF) virus isolations were obtained from Hyalomma marginatum rufipes adult ticks collected on ungulates, 175 birds were captured and sera collected. CCHF antibodies were detected by ELISA in 6/22 red-beaked hornbills (Tockus erythrorhynchus), 2/11 glossy starlings (Lamprotornis sp.) and 1/3 guinea fowls. The virus was isolated from H. m. rufipes nymphs collected on a hornbill. The role of wild ground-feeding birds in CCHF virus ecology in West Africa is discussed.

  1. Uranium concentrations in the phosphates of Congo related to marin and continental mineral authigenesis

    International Nuclear Information System (INIS)

    Giresse, P.; N'Landou, J. de Dieu; Wiber, M.

    1984-01-01

    In the Maastrichtian phosphates of Tchivoula (Congo), uanium, for the most part fixed and tetravalent in marine apatites in there after mobilized and occasionally concentrates during the course of successive stages of dissolution, recrystallization (secondary apatite) or authigenesis (ferro-aluminous phosphates, autunite and torbernite). Very high levels near the top of the deposit appear to be related to the percolation of uraniferous solutions from Ypresian phosphatic beds which are no longer present. In the marine Tertiary phosphates of Djeno, diagenesis is less advanced; radial changes in uranium concentration on the scale of individual coprolites of selacians can be observed and are related to the loss of P 2 O 5 [fr

  2. Report of the first case of Crimean Congo hemorrhagic fever in Qazvin Province (2016

    Directory of Open Access Journals (Sweden)

    AR. Nikoonejad

    2016-12-01

    Full Text Available Crimean Congo hemorrhagic fever is a potentially fatal disease that is reported from Asia, Africa and Europe. In May, 2016 a 42 year-old female is admitted to Buali-Sina hospital with epistaxis and within a few hours got loss of consciousness and shock. The patient was put on supportive care and oral Ribavirin. From the sixth admission day, the general condition of the patient improved and on the eleventh day she was discharged without an important sequela. Consequently, it is necessary to consider this disease in the differential diagnosis of all patients presented with fever and acute bleeding diathesis.

  3. Advocacy Narratives and Celebrity Engagement: the Case of Ben Affleck in Congo

    DEFF Research Database (Denmark)

    Budabin, Alexandra Cosima; Richey, Lisa Ann

    2018-01-01

    shape human rights narratives by selecting issues and interacting with dominant framings. This hypothesis is tested through a discourse analysis of professional entertainer Ben Affleck’s spoken and written texts along with organizational materials covering the establishment of the Eastern Congo...... Initiative. The study explains how the ability for celebrities to contend with narratives reflects elite practices in human rights advocacy.......Global celebrities are increasingly important in human rights--promoting causes, raising awareness, and interacting with decision-makers—as communicators to mass and elite audiences. Deepening the literature on transnational advocacy and North-South relations, this article argues that celebrities...

  4. Comparing the Performance of Faith-Based and Government Schools in the Democratic Republic of Congo

    OpenAIRE

    Backiny-Yetna, Prospere; Wodon, Quentin

    2009-01-01

    This paper provides a comparative assessment of the market share, reach to the poor, and performance of faith-based and public schools in the Democratic Republic of Congo using data from the 2004-2005 "123" survey. More than two thirds of primary school students attend faith-based government-assisted schools. Both types of school cater to a similar population that is overwhelmingly poor. Faith-based schools perform slightly better at least in some dimensions than government schools, but the ...

  5. Woodlands Grazing Issues in Mediterranean Basin

    Science.gov (United States)

    Campos, P.

    2009-04-01

    In Mediterranean basin, woodlands grazing still continue to be important commercial owners' benefits. These owners manage woodlands vegetations as if they were not at risk of degradation and declining. Frequently, no temporally grazing set-aside is taken into account to avoid overgrazing of annual and perennial vegetations. Although less common, in the northern shore of Mediterranean basin undergrazing might increase the frequency and the number of catastrophic forest fires. This under/over grazing regime occurs in the Mediterranean basin woodlands with contrasted differences on land property rights, local economies and government livestock policy incentives. Spain and Tunisia are examples of these Mediterranean livestock contrasts. Most of Spanish Mediterranean woodlands and livestock herds are large private ownerships and owners could maintain their lands and livestock herds properties on the basis of moderate cash-income compensation against land revaluation and exclusive amenity self-consumption. The later is less tangible benefit and it could include family land legacy, nature enjoyment, country stile of life development, social status and so on. In public woodlands, social and environmental goals -as they are cultural heritage, biodiversity loss mitigation, soil conservation and employment- could maintain market unprofitable woodlands operations. Last three decades Spanish Mediterranean woodlands owners have increased the livestock herds incentivized by government subsidies. As result, grazing rent is pending on the level of European Union and Spanish government livestock subsidies. In this context, Spanish Mediterranean woodlands maintain a high extensive livestock stoking population, which economy could be called fragile and environmentally unsustainable because forest degradation and over/under grazing practices. Tunisian Mediterranean woodlands are state properties and livestock grazing is practice as a free private regimen. Livestock herds are small herd

  6. European mixed forests

    DEFF Research Database (Denmark)

    Bravo-Oviedo, Andres; Pretzsch, Hans; Ammer, Christian

    2014-01-01

    Aim of study: We aim at (i) developing a reference definition of mixed forests in order to harmonize comparative research in mixed forests and (ii) review the research perspectives in mixed forests. Area of study: The definition is developed in Europe but can be tested worldwide. Material...... and Methods: Review of existent definitions of mixed forests based and literature review encompassing dynamics, management and economic valuation of mixed forests. Main results: A mixed forest is defined as a forest unit, excluding linear formations, where at least two tree species coexist at any...... density in mixed forests, (iii) conversion of monocultures to mixed-species forest and (iv) economic valuation of ecosystem services provided by mixed forests. Research highlights: The definition is considered a high-level one which encompasses previous attempts to define mixed forests. Current fields...

  7. Forest tenure and sustainable forest management

    Science.gov (United States)

    J.P. Siry; K. McGinley; F.W. Cubbage; P. Bettinger

    2015-01-01

    We reviewed the principles and key literature related to forest tenure and sustainable forest management, and then examined the status of sustainable forestry and land ownership at the aggregate national level for major forested countries. The institutional design principles suggested by Ostrom are well accepted for applications to public, communal, and private lands....

  8. Effect of Diffusion on Discoloration of Congo Red by Alginate Entrapped Turnip (Brassica rapa Peroxidase

    Directory of Open Access Journals (Sweden)

    Afaf Ahmedi

    2015-01-01

    Full Text Available Enzymatic discoloration of the diazo dye, Congo red (CR, by immobilized plant peroxidase from turnip “Brassica rapa” is investigated. Partially purified turnip peroxidase (TP was immobilized by entrapment in spherical particles of calcium alginate and was assayed for the discoloration of aqueous CR solution. Experimental data revealed that pH, reaction time, temperature, colorant, and H2O2 concentration play a significant role in dye degradation. Maximum CR removal was found at pH 2.0, constant temperature of 40°C in the presence of 10 mM H2O2, and 180 mg/L of CR. More than 94% of CR was removed by alginate immobilized TP after 1 h of incubation in a batch process under optimal conditions. About 74% removal efficiency was retained after four recycles. Diffusional limitations in alginate beads such as effectiveness factor η, Thiele modulus Φ, and effective diffusion coefficients (De of Congo red were predicted assuming a first-order biodegradation kinetic. Results showed that intraparticle diffusion resistance has a significant effect on the CR biodegradation rate.

  9. [Preliminary results of an herpetology investigation in sugar cane plantation in Democratic Republic of Congo].

    Science.gov (United States)

    Malukisa, J; Collet, M; Bokata, S; Odio, W

    2005-11-01

    Out of the 3,000 species of snakes described in the world, 163 are currently known from D.R. of Congo. We performed a systematic survey in sugar-cane plantations of the Sugar Company of Kwilu-Ngongo (Bas-Congo), located at 160 km South-West from Kinshasa and exploiting nearly 10,000 ha. The plantation is divided into 3 sectors in the middle of which we deposited barrels filled of formaldehyde. All the employees of the Sugar Company of Kwilu-Ngongo were requested to collect encountered snakes and put them in the nearest barrel. Between August 9th and September 21st, 2004, we collected 36 snakes in two different sites, revealing the presence of 3 families and 12 species. The most abundant species in Causus maculatus (47% in the first site--Point 8--and 29% in the second site--Point 13). The most poisonous and dangerous species were captured only in the first site--point 8, and were Dendroaspis jamesoni and Naja melanoleuca, both young.

  10. Prevalence of Campylobacter among goats and retail goat meat in Congo.

    Science.gov (United States)

    a Mpalang, Rosette Kabwang; Boreux, Raphaël; Melin, Pierrette; Akir Ni Bitiang, Khang'Mate; Daube, Georges; De Mol, Patrick

    2014-02-13

    The prevalence of Campylobacter jejuni and Campylobacter coli was determined in goat and goat meat sold at retail outlets in Lubumbashi, Democratic Republic of Congo (DR Congo). A total of 644 samples, including 177 goat meat, 86 goat stomachs, 139 ready to eat (RTE) goat skewers, and 242 goat faecal samples were examined for the presence of Campylobacter jejuni and Campylobacter coli using polymerase chain reaction. Overall, Campylobacter spp. were found in 34.6% of the examined samples. C. jejuni was isolated in 10.1% and C. coli in 26.7% of samples. Only 2.2% of all samples were positive for both species. There was a significant association between the prevalence of C. coli and the type of sample (p goat meat, goat stomachs, RTE goat skewers, and goat faecal samples, respectively. There was no significant difference (p > 0.05) between the prevalence observed in the rainy season (16.7%) and the dry season (20.0%). Moreover, the overall prevalence of Campylobacter in slaughter sites, open-air markets, warehouses, and semi-open-air markets was 28.2%, 34.2%, 35.4%, and 42.9%, respectively. Statistically, there was no influence of the sample collection site on the frequency of isolation of Campylobacter (p > 0.05). This study shows that, considering the relatively high prevalence of this pathogen, live goat and goat meat are major sources of human and environmental contamination by Campylobacter spp. in Lubumbashi.

  11. Adsorption of Congo red dye onto antimicrobial terephthaloyl thiourea cross-linked chitosan hydrogels.

    Science.gov (United States)

    El-Harby, Nouf F; Ibrahim, Shaimaa M A; Mohamed, Nadia A

    2017-11-01

    Adsorption capacity of three antimicrobial terephthaloyl thiourea cross-linked chitosan hydrogels for Congo red dye removal from its aqueous solution has been investigated for the first time in this work. These hydrogels were prepared by reacting chitosan with various amounts of terephthaloyl diisothiocyanate cross-linker. The effect of the hydrogel structural variations and several dye adsorption processing parameters to achieve the best adsorption capacity were investigated. The hydrogels' structural variations were obtained by varying their terephthaloyl thiourea moieties content. The processing variables included initial concentration of the dye solution, temperature and time of exposure to the dye. The adsorption kinetics and isotherms showed that the sorption processes were better fitted by the pseudo-second-order equation and the Langmuir equation, respectively. On the basis of the Langmuir analysis Congo red dye gave the maximum sorption capacity of 44.248 mg/g. The results obtained confirmed that the sorption phenomena are most likely to be controlled by chemisorption process. The adsorption reaction was endothermic and spontaneous according to the calculated results of adsorption thermodynamics.

  12. Removal of toxic Congo red dye from water employing low-cost coconut residual fiber.

    Science.gov (United States)

    Rani, K C; Naik, Aduja; Chaurasiya, Ram Saran; Raghavarao, K S M S

    2017-05-01

    The coconut residual fiber (CRF) is the major byproduct obtained during production of virgin coconut oil. Its application as a biosorbent for adsorption of Congo red was investigated. The CRF was subjected to different pretreatments, namely, pressure cooking, hexane treatment, acid treatment and their combinations. The pretreatment of CRF with the combination of hexane, acid, and pressure cooking resulted in the highest degree of adsorption. The equilibrium data were analyzed and found to fit best to both Langmuir and Freundlich isotherms. Thermodynamic parameters such as standard free energy (ΔG 0 kJ mol -1 ), standard enthalpy (ΔH 0 , kJ mol -1 ) and standard entropy (ΔS 0 , kJ mol -1 K -1 ) of the systems were calculated by using the Langmuir constant. The ΔG 0 , ΔH 0 and ΔS 0 were found to be 16.51 kJ mol -1 , -19.39 kJ mol -1 and -0.12 kJ mol -1 K -1 , respectively, at 300 K. These thermodynamic parameters suggest the present adsorption process to be non-spontaneous and exothermic. The adsorption process was observed to follow pseudo-second-order kinetics. The results suggest that CRF has potential to be a biosorbent for the removal of hazardous material (Congo red dye) with a maximum adsorption capacity of 128.94 mg g -1 at 300 K.

  13. Adsorptive removal of congo red and sunset yellow dyes from water systems by lady finger stem

    International Nuclear Information System (INIS)

    Abbas, A.; Murtaza, S.; Ayub, R.; Rehman, R.; Zahid, A.

    2012-01-01

    Summary: In this research work two anionic dyes, i.e. Congo Red and Sunset Yellow were removed successfully from aqueous media by Lady Finger stem in batch mode. Operational conditions optimization showed that agitation speed and particle size did not affect much in adsorption of these dyes; but contact time, pH, adsorbent dose and temperature of system effects the adsorption rate. Optimized conditions of adsorption for Congo Red dye were: 40 minute contact time, 8.0 pH, 0.5 g adsorbent dose, 40-60 microns mesh sized particles, 150 rpm agitation speed and 50 degree C temperature. Whereas for Sunset Yellow optimized conditions were: 30 minute contact time, 2.0 pH, 2.5 g adsorbent dose, 20-40 microns mesh sized particles, 50 rpm agitation speed and 30 degree C temperature. Suitability of equilibrium data was modulated with Langmuir, Freundlich and Temkin models and found that both physisorption and chemisorption processes play important role in adsorption of these dyes by Lady Finger stem. The results demonstrated that Lady Finger stem can be efficiently employed on larger scale wastewater treatment. (author)

  14. Retinoblastoma in the Democratic Republic of Congo: 20-Year Review from a Tertiary Hospital in Kinshasa

    Directory of Open Access Journals (Sweden)

    Aimé Kazadi Lukusa

    2012-01-01

    Full Text Available Background. To determine clinical profile and management of retinoblastoma among children at Kinshasa in Democratic Republic of Congo. Patients and methods. The medical records of patients with a diagnosis of retinoblastoma seen at the University Hospital of Kinshasa from January 1985 till December 2005 were retrospectively reviewed. Demographic profile, clinical data, modes of treatment and outcome were analysed. Results. A total of 49 children, of whom 40 had adequate data on record were identified as retinoblastoma (28 males and 12 females. Nine cases had bilateral disease. The median age at the first symptoms was 9 months (range, 1 month to 6 years for unilateral retinoblastoma and 18 months (range, 1 month to 3.5 years for bilateral retinoblastoma. The median age at the first oncology consultation was 2.4 years (range, 6 months to 6 years for unilateral retinoblastoma and 2.4years (range, 9 months to 4 years for bilateral disease. Leukokoria was present in 67.5% of subjects. Seventy-five percent abandoned the treatment. The mortality was 92.5%. Conclusion. In Democratic Republic of Congo, retinoblastoma remains a life threatening disease characterized by late referral to a specialized unit and affordability of chemotherapy; all leading to an extension of the disease and high mortality.

  15. A new test of amyloidisis screening with 123 radioiodine congo red

    International Nuclear Information System (INIS)

    Behar, A.; Herremann, G.; Coornaert, S.; Cohen-Boulakia, F.; Bardy, A.; Bismut, F.; Baillet, J.

    1984-01-01

    The purpose of our study was to find a simple and reliable alternative to multiple and repetitive biopsies required for diagnosing amyloidosis which would also serve to evaluate the outcome of treatment. The old Congo red test which is based on the disappearance of the indicator from the blood was abandoned because it gave inconsistent and late results. Instead, Congo red was labeled with the iodogen method using 123-iodine. The evaluation method we would like to propose is based on 24-hour imaging over the heart, the liver and the kidneys. In 12 normal subjects and 10 patients with non-amyloid cardiomyopathies the exponential response curve recorded was found to have an identical slope. Patients with amyloidosis, by contrast, showed a biphasic kinetic pattern with e sup(-Λt) and I-e sup(-Λt) on account of the trapping of the indicator (25 subjects with bioptically verified diagnoses). False negative results were absent, but in patients without amyloidosis a positive response was at times seen in one organ, e.g. the liver in patients with steatosis or the heart in patients with severe heart failure. (Author)

  16. Meeting report: First International Conference on Crimean-Congo hemorrhagic fever.

    Science.gov (United States)

    Papa, Anna; Weber, Friedemann; Hewson, Roger; Weidmann, Manfred; Koksal, Iftihar; Korukluoglu, Gulay; Mirazimi, Ali

    2015-08-01

    Crimean-Congo hemorrhagic fever (CCHF) is the most widespread tick-borne disease of humans, occurring from western China to the Balkans in Eurasia and south throughout the length of Africa. Its incidence has increased over the past decade, particularly in Turkey and Iran, and the disease has also emerged in India. Research has been hindered by limited laboratory capacity in many regions where the disease is prevalent, indicating the need for collaboration between investigators in endemic countries and those with greater scientific resources. In an effort to increase such collaboration, the First International Conference on Crimean-Congo hemorrhagic fever was held in Thessaloniki, Greece, from February 13 to 14, 2015. This meeting followed the conclusion of an EU-supported Collaborative Project under the Health Cooperation Work Programme of the 7th Framework Programme (Grant agreement No. 260427). It is expected to be the first in a series of meetings that will bring together researchers from around the world to exchange knowledge and experience on various aspects of CCHF. This report summarizes major presentations by the invited speakers at the First International Conference on CCHF. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. EPIDEMIOLOGY, CLINICAL AND LABORATORY FEATURES OF CRIMEAN-CONGO HEMORRHAGIC FEVER IN GEORGIA.

    Science.gov (United States)

    Vashakidze, E; Mikadze, I

    2015-10-01

    Crimean-Congo hemorrhagic fever virus transmitted to humans by Hyalomma ticks or by direct contact with the blood of infected humans or domestic animals. The most common clinical signs of CCHF are fever, nausea, headache, diarrhea, myalgia, petechial rash, and bleeding. CCHF is a severe disease in humans with a fatality rate up to 15-85%. This study was undertaken to determine the predictors of fatality among patients with CCHF based on epidemiological, clinical, and laboratory findings. 34 patients were enrolled in the study, aged 4 to 77; 17 - male and 17 female. 3 of them were fatal cases. All of them were from Shua Kartli: Khashuri, Gori and Kaspi districts, involved in farming/handling livestock and the history of tick bite was present in most of patients. Evaluation of the epidemiological characteristics of this cases showed that the female to male ratio was nearly similar. The disease is common in the rural areas of the region, mostly in the actively working age group and almost all patients were farmers. The results of our study show that the most cardinal clinical and laboratory features of Crimean-Congo hemorrhagic fever are - acute beginning of disease, high fever, intoxication and hemorrhagic symptoms, thrombocytopenia, high level of aminotransferases and creatine. Predictors of fatality are: an altered mental status, in early stage of disease dramatic decreased thrombocytes count and significantly high level of aspartate aminotransferase, also longer the mean prothrombin time and INR.

  18. Mammals consumed by bonobos (Pan paniscus): new data from the Iyondji forest, Tshuapa, Democratic Republic of the Congo.

    Science.gov (United States)

    Sakamaki, Tetsuya; Maloueki, Ulrich; Bakaa, Batuafe; Bongoli, Lingomo; Kasalevo, Phila; Terada, Saeko; Furuichi, Takeshi

    2016-07-01

    Findings of regional variations in the behavioral patterns of non-human primates have led to the vigorous study of animal traditions (or culture), which contribute to a biological understanding of diversity in human cultures. Although our knowledge of behavioral variations of the bonobo (Pan paniscus) is limited compared with its sister species, the chimpanzee (P. troglodytes), variations in the prey of this species have been reported across study sites. This study describes evidence of mammals consumed by bonobos in the Iyondji site, which was established in 2010. We found evidence that Iyondji bonobos consumed duikers (Cephalophus dorsalis, C. monticola) and diurnal monkeys (Cercopithecus ascanius), which is notable because only anomalures (Anomalurus spp.) are consumed by bonobos in Wamba, a long-term study site established in 1973, located in an area adjacent to Iyondji. Moreover, bonobos do not transfer between the two populations due to the river between the sites. According to our census of duikers and diurnal monkeys, Iyondji bonobos appeared to encounter diurnal monkeys more frequently than did Wamba bonobos. Although humans have apparently had a more pronounced impact on the habitats in Wamba than on those in Iyondji, it remains unclear how such environmental conditions may have contributed to the differences in the prey consumed by bonobos in different sites. Our findings suggest that additional research at various sites could reveal the nature of the variations in the behavior of bonobos.

  19. Height-diameter allometry and above ground biomass in tropical montane forests: Insights from the Albertine Rift in Africa.

    Science.gov (United States)

    Imani, Gérard; Boyemba, Faustin; Lewis, Simon; Nabahungu, Nsharwasi Léon; Calders, Kim; Zapfack, Louis; Riera, Bernard; Balegamire, Clarisse; Cuni-Sanchez, Aida

    2017-01-01

    Tropical montane forests provide an important natural laboratory to test ecological theory. While it is well-known that some aspects of forest structure change with altitude, little is known on the effects of altitude on above ground biomass (AGB), particularly with regard to changing height-diameter allometry. To address this we investigate (1) the effects of altitude on height-diameter allometry, (2) how different height-diameter allometric models affect above ground biomass estimates; and (3) how other forest structural, taxonomic and environmental attributes affect above ground biomass using 30 permanent sample plots (1-ha; all trees ≥ 10 cm diameter measured) established between 1250 and 2600 m asl in Kahuzi Biega National Park in eastern Democratic Republic of Congo. Forest structure and species composition differed with increasing altitude, with four forest types identified. Different height-diameter allometric models performed better with the different forest types, as trees got smaller with increasing altitude. Above ground biomass ranged from 168 to 290 Mg ha-1, but there were no significant differences in AGB between forests types, as tree size decreased but stem density increased with increasing altitude. Forest structure had greater effects on above ground biomass than forest diversity. Soil attributes (K and acidity, pH) also significantly affected above ground biomass. Results show how forest structural, taxonomic and environmental attributes affect above ground biomass in African tropical montane forests. They particularly highlight that the use of regional height-diameter models introduces significant biases in above ground biomass estimates, and that different height-diameter models might be preferred for different forest types, and these should be considered in future studies.

  20. Restoring forests

    DEFF Research Database (Denmark)

    Jacobs, Douglass F.; Oliet, Juan A.; Aronson, James

    2015-01-01

    of land requiring restoration implies the need for spatial prioritization of restoration efforts according to cost-benefit analyses that include ecological risks. To design resistant and resilient ecosystems that can adapt to emerging circumstances, an adaptive management approach is needed. Global change......, in particular, imparts a high degree of uncertainty about the future ecological and societal conditions of forest ecosystems to be restored, as well as their desired goods and services. We must also reconsider the suite of species incorporated into restoration with the aim of moving toward more stress resistant...... and competitive combinations in the longer term. Non-native species may serve an important role under some circumstances, e.g., to facilitate reintroduction of native species. Propagation and field establishment techniques must promote survival through seedling stress resistance and site preparation. An improved...