Evaluation of soil and water salinity for irrigation in North-eastern Ethiopia: Case study of Fursa small scale irrigation system in Awash River Basin

For sound land use and water management in irrigated area, knowledge of the chemical composition of soils, water, climate, drainage condition and irrigation methods before action are crucial for sustainability of irrigation projects. The study aimed to evaluate the physicochemical properties of soils and water for intended irrigation scheme with reference to standard suitability classes. With regard to this, a study was conducted in Awash River Basin at Fursa small scale irrigation scheme in Northeastern Ethiopia. Soil samples were collected from bore holes of three soil mapping units of the study site across depth and water samples were taken from irrigation water with plastic bottles for analysis of range of physical and chemical properties. The results of the analysis reveal the existence of potential sodicity not only in the soil but also in the irrigation water. The study underlines the need for selection of salt tolerant crops and good water management by using appropriate irrigation methods to sustain productivity of soil in the proposed irrigation site. This has significant contribution to deciding the type of crop to be produced and appropriate irrigation methods for sustainability of soil productivity.Key words: Fursa irrigation scheme, salinity, sodicity, soil analysis, water analysis

Reactive nitrogen in Asian continental outflow over the western Pacific: Results from the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) airborne mission

We present here results for reactive nitrogen species measured aboard the NASA DC-8 aircraft during the Transport and Chemical Evolution over the Pacific (TRACE-P) mission. The large-scale distributions total reactive nitrogen (NOy,sum = NO + NO2 + HNO3 + PAN + C1–C5alkyl nitrates) and O3 and CO were better defined in the boundary layer with significant degradation of the relationships as altitude increased. Typically, NOy,sum was enhanced over background levels of ∼260 pptv by 20-to-30-fold. The ratio C2H2/CO had values of 1–4 at altitudes up to 10 km and as far eastward as 150°E, implying significant vertical mixing of air parcels followed by rapid advection across the Pacific. Analysis air parcels originating from five principal Asian source regions showed that HNO3 and PAN dominated NOy,sum. Correlations of NOy,sum with C2Cl4 (urban tracer) were not well defined in any of the source regions, and they were only slightly better with CH3Cl (biomass tracer). Air parcels over the western Pacific contained a complex mixture of emission sources that are not easily resolvable as shown by analysis of the Shanghai mega-city plume. It contained an intricate mixture of pollution emissions and exhibited the highest mixing ratios of NOy,sum species observed during TRACE-P. Comparison of tropospheric chemistry between the earlier PEM-West B mission and the recent TRACE-P data showed that in the boundary layer significant increases in the mixing ratios of NOy,sum species have occurred, but the middle and upper troposphere seems to have been affected minimally by increasing emissions on the Asian continent over the last 7 years

Spatial tethering of kinases to their substrates relaxes evolutionary constraints on specificity

Signal transduction proteins are often multi-domain proteins that arose through the fusion of previously independent proteins. How such a change in the spatial arrangement of proteins impacts their evolution and the selective pressures acting on individual residues is largely unknown. We explored this problem in the context of bacterial two-component signalling pathways, which typically involve a sensor histidine kinase that specifically phosphorylates a single cognate response regulator. Although usually found as separate proteins, these proteins are sometimes fused into a so-called hybrid histidine kinase. Here, we demonstrate that the isolated kinase domains of hybrid kinases exhibit a dramatic reduction in phosphotransfer specificity in vitro relative to canonical histidine kinases. However, hybrid kinases phosphotransfer almost exclusively to their covalently attached response regulator domain, whose effective concentration exceeds that of all soluble response regulators. These findings indicate that the fused response regulator in a hybrid kinase normally prevents detrimental cross-talk between pathways. More generally, our results shed light on how the spatial properties of signalling pathways can significantly affect their evolution, with additional implications for the design of synthetic signalling systems.National Science Foundation (U.S.) (CAREER Award)National Science Foundation (U.S.). Graduate Research Fellowship Progra

Identifying best crop management practices for chickpea (Cicer arietinum L .) in Northeastern Ethiopia under climate change condition

Chickpea (Cicer arietinum L.) is one of the important cool season food legumes in the semi-arid northeastern Ethiopia; however, its productivity is adversely affected by a number of abiotic and biotic factors. The objectives of this study were to assess impacts of projected climate change on grain yield of chickpea by 2030 s (2020–2049) and 2050 s (2040–2069) and to identify crop management options that increase productivity of the crop. The CROPGRO-chickpea model in DSSAT (Decision Support System for Agrotechnology Transfer) was used to assess impacts of projected climate change on chickpea and to identify adaptation options. The crop model was first calibrated and evaluated in the study area for simulating growth, yield and water balance of the soil. The result of the model calibration and evaluation showed that there were close agreement between the simulated and observed values that showed the performance of the model to simulate growth, phenology and yield of chickpea under semi-arid northeastern Ethiopian condition. The calibrated model was used to assess impacts of projected climate changes on chickpea and identify crop management options. The impact of projected climate change was assessed for 2030 s and 2050 s time periods under all the RCPs with and without CO2 fertilization. To identify crop management options, different varieties of chickpea, supplemental irrigation and change in planting dates have been evaluated. The result of climate change impact analysis on chickpea showed that grain yield is predicted to significantly increase both by 2030 s and 2050 s under CO2 fertilization condition across all the RCPs as compared to baseline grain yield (1961–1990). However, simulation without CO2 showed that grain yield will not significantly increase by 2030 s and 2050 s across all the scenarios. Based on the prediction result it can be generalized that chickpea will be benefited from the projected climate changes in northeastern Ethiopia. According to the simulation result application of two supplemental irrigation (flower initiation and pod setting stages) and early sowing significantly (P < 0.05) increase grain yield of chickpea in northeastern Ethiopia under the present and future climate conditions. Selection of appropriate cultivars based on the agroecology of the area has paramount important to increase chickpea productivity under the present and future climate condition

Steady state free radical budgets and ozone photochemistry during TOPSE

A steady state model, constrained by a number of measured quantities, was used to derive peroxy radical levels for the conditions of the Tropospheric Ozone Production about the Spring Equinox (TOPSE) campaign. The analysis is made using data collected aboard the NCAR/NSF C-130 aircraft from February through May 2000 at latitudes from 40° to 85°N, and at altitudes from the surface to 7.6 km. HO2 + RO2 radical concentrations were measured during the experiment, which are compared with model results over the domain of the study showing good agreement on the average. Average measurement/model ratios are 1.04 (σ = 0.73) and 0.96 (σ = 0.52) for the MLB and HLB, respectively. Budgets of total peroxy radical levels as well as of individual free radical members were constructed, which reveal interesting differences compared to studies at lower latitudes. The midlatitude part of the study region is a significant net source of ozone, while the high latitudes constitute a small net sink leading to the hypothesis that transport from the middle latitudes can explain the observed increase in ozone in the high latitudes. Radical reservoir species concentrations are modeled and compared with the observations. For most conditions, the model does a good job of reproducing the formaldehyde observations, but the peroxide observations are significantly less than steady state for this study. Photostationary state (PSS) derived total peroxy radical levels and NO/NO2ratios are compared with the measurements and the model; PSS-derived results are higher than observations or the steady state model at low NO concentrations

A Framework for Bundling Climate-Smart Agriculture (CSA) and Climate Information Services (CIS) in Ethiopia

Ethiopia is increasingly impacted by climate change and variability because of its greater reliance on climate-sensitive economic sectors such as agriculture. The impacts of climate change and variability are greater on a poor section of the rural community in particular because of their weak adaptive capacities. In recent years, there has been an increasing focus on promoting climate-smart agriculture (CSA) and climate information services (CIS) to improve climate risk management and adaptation of smallholders to climate change in Ethiopia. However, CSA and CIS are rarely provided to farmers in an integrated manner. Therefore, considering the current agricultural technology development and dissemination landscape and the growing digital climate agro-advisory services in the country, a CSA and CIS budling framework is developed for Ethiopia. Bundling of CSA and CIS is expected to empower farmers to make appropriate decisions on a seasonal and intra-seasonal basis, minimize 'technology failure' due to climate variability and enhance adoption of new or existing CSA technologies/practices, reduce yield loss due to climate variability, and farm costs, and increase household income and food security and enhances resilience. Moreover, the bundling framework creates an opportunity for a platform to integrate tools, technologies, and services provided by different institutions and actors. The framework is validated through stakeholder feedback, and it is expected to guide the scaling of bundled services to smallholders

Evaluation of the health-related quality of life of children in Schistosoma haematobium-endemic communities in Kenya: a cross-sectional study.

BACKGROUND: Schistosomiasis remains a global public health challenge, with 93% of the ~237 million infections occurring in sub-Saharan Africa. Though rarely fatal, its recurring nature makes it a lifetime disorder with significant chronic health burdens. Much of its negative health impact is due to non-specific conditions such as anemia, undernutrition, pain, exercise intolerance, poor school performance, and decreased work capacity. This makes it difficult to estimate the disease burden specific to schistosomiasis using the standard DALY metric. METHODOLOGY/PRINCIPAL FINDINGS: In our study, we used Pediatric Quality of Life Inventory (PedsQL), a modular instrument available for ages 2-18 years, to assess health-related quality of life (HrQoL) among children living in a Schistosoma haematobium-endemic area in coastal Kenya. The PedsQL questionnaires were administered by interview to children aged 5-18 years (and their parents) in five villages spread across three districts. HrQoL (total score) was significantly lower in villages with high prevalence of S. haematobium (-4.0%, p<0.001) and among the lower socioeconomic quartiles (-2.0%, p<0.05). A greater effect was seen in the psychosocial scales as compared to the physical function scale. In moderate prevalence villages, detection of any parasite eggs in the urine was associated with a significant 2.1% (p<0.05) reduction in total score. The PedsQL reliabilities were generally high (Cronbach alphas ≥0.70), floor effects were acceptable, and identification of children from low socioeconomic standing was valid. CONCLUSIONS/SIGNIFICANCE: We conclude that exposure to urogenital schistosomiasis is associated with a 2-4% reduction in HrQoL. Further research is warranted to determine the reproducibility and responsiveness properties of QoL testing in relation to schistosomiasis. We anticipate that a case definition based on more sensitive parasitological diagnosis among younger children will better define the immediate and long-term HrQoL impact of Schistosoma infection