Hydrochemical studies of Cross River Basin (southeastern Nigeria) river systems using cross plots, statistics and water quality index

Water quality assessment study of the three major rivers within the Cross River Basin have been carried out using cross plots, ionic ratio, correlation analysis, factor analysis and water quality index (WQI) based on the World Health Organization and world average data guidelines. The primary aim was to determine their suitability for domestic and irrigation uses, while the secondary aim was to determine the sources of the ions in the river water. The results showed that the water samples from the Cross River estuary generally had elevated values of dissolved ions as compared to the Calabar and Great Kwa Rivers. Cross plots, ionic ratios, correlation and factor analyses showed tidal influence, silicate weathering, nitrate pollution and dissolution of carbonate minerals from soil CO₂ as the origin of the variables. Chemical indices including sodium adsorption ratio and residual sodium carbonate indicate that the river water of the study area are suitable for domestic and irrigation, while sodium percentage (Na %) indicate unsuitability for irrigation applications. The WQI values on the average indicate water of very poor to excellent quality. Generally in terms of quality for the different rivers, the Great Kwa River is best as compared to the Calabar River and Cross River estuary for domestic and irrigation purposes.     

Impacts and adaptation to climate change in European economies

This paper evaluates the impacts of climate change to European economies under an increase in global mean temperature at +2 °C and +4 °C. It is based on a summary of conclusions from available studies of how climate change may affect various sectors of the economies in different countries. We apply a macroeconomic general equilibrium model, which integrates impacts of climate change on different activities of the economies. Agents adapt by responding to the changes in market conditions following the climatic changes, thus bringing consistency between economic behaviour and adaptation to climate change. Europe is divided into 85 sub-regions in order to capture climate variability and variations in vulnerabilities within countries. We find that the impacts in the +2 °C are moderate throughout Europe, with positive impacts on GDP in some sub-regions and negative impacts down to 0.1 per cent per year in others. At +4 °C, GDP is negatively affected throughout Europe, and most substantially in the southern parts, where it falls by up to 0.7 per cent per year in some sub-regions. We also find that climate change causes differentiations in wages across Europe, which may cause migration from southern parts of Europe to northern parts, especially to the Nordic countries.     

Land tenure and REDD+: The good,the bad and the ugly

A number of international donors, national governments and project proponents have begun to lay the groundwork for REDD+, but tenure insecurity – including the potential risks of land grabbing by outsiders and loss of local user rights to forests and forest land – is one of the main reasons that many indigenous and other local peoples have publicly opposed it. Under what conditions is REDD+ a threat to local rights, and under what conditions does it present an opportunity? This article explores these issues based on available data from a global comparative study on REDD+, led by the Center for International Forestry Research, which is studying national policies and processes in 12 countries and 23 REDD+ projects in 6 countries. The article analyses how tenure concerns are being addressed at both national and project level in emerging REDD+ programs. The findings suggest that in most cases REDD+ has clearly provided some new opportunities for securing local tenure rights, but that piecemeal interventions by project proponents at the local level are insufficient in the absence of broader, national programs for land tenure reform. The potential for substantial changes in the status quo appear unlikely, though Brazil – the only one with such a national land tenure reform program – offers useful insights. Land tenure reform – the recognition of customary rights in particular – and a serious commitment to REDD+ both challenge the deep-rooted economic and political interests of ‘business as usual’.     

Minor constituents in the Martian atmosphere from the ISM/Phobos experiment

Global Martian atmospheric results derived from the infrared imaging spectrometer ISM flown aboard the Phobos 2 Soviet spacecraft are presented. Over low altitude regions the expected CO mixing ratio of (8 +/- 3) x 10(-4) is measured. Variations of the 2.35-micrometers feature are inconsistent with this value over the Great Martian Volcanoes. If the 2.35-micrometers band is entirely attributable to carbon monoxide, the CO mixing ratio is typically depleted by a factor of 3 over these high altitude areas. Orography should play a major role in the existence of this CO "hole." If, however, these spectral variations at 2.35 micrometers are due to the surface composition, the fraction of the surface covered by the responsible mineral must smoothly decrease as the surface elevation decreases. This phenomenon implies a strong interaction between the surface and the atmosphere for the Great Martian Volcanoes. Diurnal behavior and latitudinal variations of water vapor are globally consistent with Viking measurements. During the Phobos observations, the water vapor amounts over the bright equatorial regions range around 11 pr-micrometers during the day. These amounts are slightly larger than those inferred from 1976 to 1979. The lack of global dust storms during 1988-1989 could explain the enhancement of H2O in the atmosphere.     

Hydrochemical assessment of pond and stream water near abandoned barite mine sites in parts of Oban massif and Mamfe Embayment,Southeastern Nigeria

Hydrochemical studies were carried out in parts of Oban Massif and Mamfe Embayment, Southeastern Nigeria to examine the contributions of barite mining activities on water quality. Pond and stream water samples were collected from six abandoned barite mines and adjoining streams areas during dry and wet seasons. These samples were analysed for physicochemical parameters using standard techniques. The results showed that the quality of water samples in the vicinity of barite mine sites was characterized by low pH, low mineralization, high suspended solids and deep colour. Sodium (Na⁺) and calcium (Ca²⁺) are the dominant cations and bicarbonate (HCO₃ ^?) and sulphate (SO₄ ^2?) the dominant anions. The low concentration of dissolved silica, relatively high concentrations of Na⁺, HCO₃ ^? and SO₄ ^2? suggest a combined influence of silicate, carbonate and weathering of mine spoils. The total dissolved solids, total suspended solids, electrical conductivity and major ions (except Na⁺ and K⁺) are higher for water draining barite mines from Cretaceous sediments, while Na⁺, K⁺, Ba²⁺ are higher in basement rock areas. Correlation and factor analyses suggest that the main components of the water samples are related to anthropogenic, geogenic, mineralization and environmental controls, while Gibbs diagram plots indicate weathering as the main process controlling the chemistry of water. Computed values of hardness and some irrigational parameters showed that the pond and stream water samples are generally soft and can be used for irrigation. Generally, the water quality satisfied the WHO (2008) and NIS (2007) standards for domestic, agriculture and industrial. However, there is the need to assess the impact of the pollution on the ecosystem and human health while remediation measures are being considered.     

Water and related chemistry in the solar system. A guaranteed time key programme for Herschel

“Water and related chemistry in the Solar System” is a Herschel Space Observatory Guaranteed-Time Key Programme. This project, approved by the European Space Agency, aims at determining the distribution, the evolution and the origin of water in Mars, the outer planets, Titan, Enceladus and the comets. It addresses the broad topic of water and its isotopologues in planetary and cometary atmospheres. The nature of cometary activity and the thermodynamics of cometary comae will be investigated by studying water excitation in a sample of comets. The D/H ratio, the key parameter for constraining the origin and evolution of Solar System species, will be measured for the first time in a Jupiter-family comet. A comparison with existing and new measurements of D/H in Oort-cloud comets will constrain the composition of pre-solar cometary grains and possibly the dynamics of the protosolar nebula. New measurements of D/H in giant planets, similarly constraining the composition of proto-planetary ices, will be obtained. The D/H and other isotopic ratios, diagnostic of Mars’ atmosphere evolution, will be accurately measured in H₂O and CO. The role of water vapor in Mars’ atmospheric chemistry will be studied by monitoring vertical profiles of H₂O and HDO and by searching for several other species (and CO and H₂O isotopes). A detailed study of the source of water in the upper atmosphere of the Giant Planets and Titan will be performed. By monitoring the water abundance, vertical profile, and input fluxes in the various objects, and when possible with the help of mapping observations, we will discriminate between the possible sources of water in the outer planets (interplanetary dust particles, cometary impacts, and local sources). In addition to these inter-connected objectives, serendipitous searches will enhance our knowledge of the composition of planetary and cometary atmospheres.     

The chemical atmospheric composition of the giant planets

For a long time it was believed that the atmospheres of the giant planets, dominated by molecular hydrogen and helium, were similar in composition to the primordial nebula from which they formed. However, this image has strongly evolved over the past twenty years, due to new developments of ground-based infrared spectroscopy, coupled with the success of the Voyager space mission.Significant differences were measured in the abundances of helium, deuterium and carbon of the four giant planets. The variations in the C/H and D/H ratios have given support to the "nucleation" formation scenario, in which the four giant planets first accreted a nucleus of about ten terrestrial masses, big enough to bind gravitationally the surrounding gaseous nebula; the helium depletion in Saturn has been interpreted as a differentiation effect in Saturn's interior; the apparent helium excess in Neptune, coupled with the recent unexpected detection of CO and HCN in this planet, might imply the presence of molecular nitrogen. In the case of Jupiter and Saturn, disequilibrium species have been detected (CO, PH₃, GeH₄, AsH₃), which are tracers of vertical dynamical motions.In the future, significant progress in our knowledge of the Jovian composition, including the noble gases, should be obtained with the mass spectrometer of the Galileo probe. The ISO mission is expected to provide new far-infrared spectroscopic data which should lead to the detection of new minor species and a better determination of the D/H ratio.     

Evolution des hydrocarbures et des populations bactériennes et microphytiques dans les sédiments des marais maritimes de l'ile grande pollués par l'Amoco cadiz: 2—Evolution des peuplements microphytiques

In this work we attempt to estimate the short- and long-term effects of the Amoco Cadiz oil spill on benthic microalgal populations (cyanophytes and diatoms) which, under natural conditions, live on upper layers of ‘schorres’ soils or of ‘slikke’ muds in the Ile Grande salt marsh system (Côtes du Nord, France). These populations were completely destroyed in 1978 in the oil-affected sites. Ubiquitous species settled fairly rapidly on intertidal polluted muds (tidal flat). The chlorophyll a content values reached 100 μg g⁻¹ dry sediment, i.e. 1000 mg m⁻² in 1980. Conversely, the salt marsh soils are still much less densely repopulated 3 years after the Amoco Cadiz grounding—especially when they are infrequently flooded (3 to 40 μg Chl.a g⁻¹, i.e. 40 to 270 mg m⁻²). Some of these soils remain ten times less populated than reference stations.     

The rotational temperature and column density of H3 in Uranus

H₃⁺ emission from Uranus has been observed repeatedly for over a decade. However, the details of the emission mechanisms are still poorly understood. In this paper, we discuss our findings from the observations we made in September 2000 and September 2001. The spectrum of Uranus was recorded at the NASA Infrared Telescope Facility using the SpeX instrument between 3 and 5 μm, with a resolving power of 1000. The 3.4–4.1 μm range permits a determination of both the H₃⁺ column density and its rotational temperature. The H₃⁺ emission, measured at 3.986 μm in the 0.8×3.7 arcsec aperture, was 0.031 Jy in September 2000 and 0.053 Jy in September 2001. The rotational temperature was found to be 560±40 K and 640±40 K in 2000 and 2001 respectively, with corresponding column densities of 5.1 (+3.2,−1.4) 10¹¹ and 4.0 (+1.8,−1.0) 10¹¹ cm⁻². These results extend the baseline for the variability study of the H₃⁺ emission (Astrophys. J. 524 (1999) 1059). Previous observations between 1992 and 1998 seemed to indicate a correlation between the H₃⁺ intensity and the solar cycle. The current data for 2000 and 2001 appear to be consistent with this general tendency.     

Airborne interferometric measurement of the infrared spectrum of Jupiter from 6 to 14 μm

A new spectrum of Jupiter from 700 to 1600 cm^?1 was obtained with an interferometric experiment using the 91.5 cm telescope of the NASA Airborne Infrared Observatory. The spectral resolution is 10 cm^?1 and the signal-to-noise ratio is 30 at 900 cm^?1. NH₃ absorption lines are observed between 820 and 1020 cm^?1. The 1306 cm^?1ν₄CH₄ band strongly appears in emission at a temperature of at least 145° K. The Jovian brightness temperature between 1400 and 1600 cm^?1, according to our measurement, is lower than 170° K.