Soils and Nutrients Losses and Gains during Rainy Season in the Fadama of Semi-Arid Sokoto, Nigeria

A study was conducted to quantify the amount of soil and plant nutrients losses and gains during rainy season in the fadama land in the Sokoto semi-arid ecosystem, Nigeria. Field measurements revealed that about 33.3 tonne ha-1 of soil was moved from the adjacent uplands by run-off and wind and subsequently deposited in the fadama, while 22 ton ha-1 was removed from the fadama land during the period of the study (May-September). Over the same period, plant nutrients losses (in kg ha-1) with the eroded soil amounted to 30.8 organic matter, 0.3 K, 9.0 Na and 0.07 available P. Nutrient gains (in kg ha-1) amounted to 2.2 Total N and 4.4 Mg. Soil deposition was found to be greater than soil removal because of the gusty winds that accompany early and late rains.The major problem of erosion in the fadama lands is the deposition of sandy materials moved from the upland which are by far less fertile. The continuous deposition of these materials could render the fertile fadama infertile. Soil removal is not a very serious threat to the fadama as soil deposition because the land is often flat and covered with vegetation in almost all part of the year with little cover in the dry season and early part of the rainy season.Key words: Nutrient losses, Erosion, Fadama, Semi-arid Sokoto and Rainy seaso

Vulgarisation de la methode du triple ensachage pour le stockage ameliore du niebe en zone sahelienne du Nord Cameroun: enjeux et perceptions paysannes

Article in French. Summary in English.The study reveals the stakes of the triple baggingmethod, assesses farmer perception about thistechnology and identifies the factors determiningtheir perception. One of the most limiting factors ofcowpea production is the storage. To solve thisproblem, Purdue University Improved CowpeaStorage Project introduced in 2010 in Cameroonthe PICS bag technology without chemical. Thesurvey revealed that pilot farmers were satisfied ofthe use of this technology. An assessment ofeconometric model pointed out an evidentcorrelation between socio-economic factors and thelevel of satisfaction of pilot farmers. Some variablesinfluenced significantly the probability of beingsatisfied, namely: the farmer experience in cowpeacropping, annual area covered by cowpea crops,the use of PICS bags without chemical, healthprotection and the potential use of PICS bags tostore other crops. Farmers are willing to adopt thistechnology for the storage of cowpea. A furthersurvey must be done in the future to assess thereal adoption rate and the impact of this technologyin this zone

Genetic diversity and drug resistance surveillance of Plasmodium falciparum for malaria elimination: is there an ideal tool for resource-limited sub-Saharan Africa?

The intensification of malaria control interventions has resulted in its global decline, but it remains a significant public health burden especially in sub-Saharan Africa (sSA). Knowledge on the parasite diversity, its transmission dynamics, mechanisms of adaptation to environmental and interventional pressures could help refine or develop new control and elimination strategies. Critical to this is the accurate assessment of the parasite's genetic diversity and monitoring of genetic markers of anti-malarial resistance across all susceptible populations. Such wide molecular surveillance will require selected tools and approaches from a variety of ever evolving advancements in technology and the changing epidemiology of malaria. The choice of an effective approach for specific endemic settings remains challenging, particularly for countries in sSA with limited access to advanced technologies. This article examines the current strategies and tools for Plasmodium falciparum genetic diversity typing and resistance monitoring and proposes how the different tools could be employed in resource-poor settings. Advanced approaches enabling targeted deep sequencing is valued as a sensitive method for assessing drug resistance and parasite diversity but remains out of the reach of most laboratories in sSA due to the high cost of development and maintenance. It is, however, feasible to equip a limited number of laboratories as Centres of Excellence in Africa (CEA), which will receive and process samples from a network of peripheral laboratories in the continent. Cheaper, sensitive and portable real-time PCR methods can be used in peripheral laboratories to pre-screen and select samples for targeted deep sequence or genome wide analyses at these CEAs

Infectiousness of the human population to Anopheles arabiensis by direct skin feeding in an area hypoendemic for malaria in Senegal.

Direct skin feeding experiments are sensitive assays to determine human infectiousness to mosquitoes but are rarely used in malaria epidemiological surveys. We determined the infectiousness of inhabitants of a malaria hypoendemic area in Senegal. Gametocyte prevalence by microscopy was 13.5% (26 of 192). Of all individuals who were gametocyte positive, 44.4% (11 of 25) infected ≥ 1 Anopheles arabiensis mosquito and 10.8% (54 of 500) of mosquitoes became infected. Of all individuals who were gametocyte negative by microscopy, 4.3% (7 of 162) infected ≥ 1 mosquito and 0.4% (12 of 3240) of mosquitoes became infected. The 18.2% (12 of 66) of all mosquito infections was a result of submicroscopic gametocyte carriage and two individuals without asexual parasites or gametocytes by microscopy were infectious to mosquitoes. When infectivity and local demography was taken into account, children 5-14 years of age contributed 50.8% of the human infectious reservoir for malaria. Adults and submicroscopic gametocyte carriers may contribute considerably to onward malaria transmission in our setting

Digital extension, price risk, and farm performance: experimental evidence from Nigeria

Open Access Article; Published online: 09 Jun 2021Despite decades of investment in agricultural extension, technology adoption among farmers and agricultural productivity growth in Sub-Saharan Africa remain slow. Among other shortcomings, extension systems often make recommendations that do not account for price risk or spatial heterogeneity in farmers' growing conditions. However, little is known about the effectiveness of extension approaches for nutrient management that consider these issues. We analyze the impact of farmers' access to site-specific nutrient management recommendations and to information on expected returns, provided through a digital decision support tool, for maize production. We implement a randomized controlled trial among smallholders in the maize belt of northern Nigeria. We use three waves of annual panel data to estimate immediate and longer term effects of two different extension treatments: site-specific recommendations with and without complementary information about variability in output prices and expected returns. We find that site-specific nutrient management recommendations improve fertilizer management practices and maize yields but do not necessarily increase fertilizer use. In addition, we find that recommendations that are accompanied by additional information about variability in expected returns induce larger fertilizer investments that persist beyond the first year. However, the magnitudes of these effects are small: we find only incremental increases in investments and net revenues over two treatment years