Through litter decomposition enormous amounts of carbon is emitted to the atmosphere. Numerous large-scale decomposition experiments have been conducted focusing on this fundamental soil process in order to understand the controls on the terrestrial carbon transfer to the atmosphere. However, previous studies were mostly based on site-specific litter and methodologies, adding major uncertainty to syntheses, comparisons and meta-analyses across different experiments and sites. In the TeaComposition initiative, the potential litter decomposition is investigated by using standardized substrates (Rooibos and Green tea) for comparison of litter mass loss at 336 sites (ranging from -9 to +26 °C MAT and from 60 to 3113 mm MAP) across different ecosystems. In this study we tested the effect of climate (temperature and moisture), litter type and land-use on early stage decomposition (3 months) across nine biomes. We show that litter quality was the predominant controlling factor in early stage litter decomposition, which explained about 65% of the variability in litter decomposition at a global scale. The effect of climate, on the other hand, was not litter specific and explained <0.5% of the variation for Green tea and 5% for Rooibos tea, and was of significance only under unfavorable decomposition conditions (i.e. xeric versus mesic environments). When the data were aggregated at the biome scale, climate played a significant role on decomposition of both litter types (explaining 64% of the variation for Green tea and 72% for Rooibos tea). No significant effect of land-use on early stage litter decomposition was noted within the temperate biome. Our results indicate that multiple drivers are affecting early stage litter mass loss with litter quality being dominant. In order to be able to quantify the relative importance of the different drivers over time, long-term studies combined with experimental trials are needed.

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The market gardening areas of Kodeni and Dogona are among the main market gardening sites in the city of Bobo-Dioulasso (Burkina Faso). On these vegetable perimeters, the forms of water mobilization for irrigation are essentially wells for the Kodeni site and wastewater from sewers for Dogona. In order to assess the physico-chemical quality and the level of cadmium and lead contamination in these waters, samples were taken at different points on each site and outside the site. The method used is based on the sampling of water in 0.5 liter polyethylene bottles, previously rinsed twice with the sample to be taken. The first samples are used to rinse the bottles and perform physical field analyzes which are pH, electrical conductivity (CE), temperature, salinity, turbidity and total dissolved solids (TDS). Each sample was acidified with pure analytical concentrated nitric acid (HNO3) (0.5 cm 3 in 0.5 liters of water) which was used to determine the metals. Physico-chemical analyzes and the level of cadmium and lead contamination were carried out. The results of these analyzes were processed using hydrochemical techniques (Piper diagram). Principal Component Analysis (PCA) has also been used to highlight the phenomena of mineralization of water in these market gardening areas.The results obtained show that these irrigation waters are acidic at the Kodeni site (pH = 5.49) and basic for the Dogona site (pH = 7.95). They are weakly mineralized at the Kodeni site with an average conductivity of 52.56 4µS/ cm and strongly mineralized at the market garden area of Dogona with an average conductivity of 508.4 4µS / cm. The cadmium and lead contents are sometimes higher than those recommended by the WHO (0.01 mg/ L for cadmium and 0.003 mg/ L for lead). The chemical facies give sodium calcium water. The value of the sodium absorption ratio (11.85) of the water at the Dogona site and that of the pH (5.49) at the Kodeni site show that the irrigation water is chemically unsuitable for agricultural use during the dry season.

The study parameters: pH, conductivity, salinity, Total Dissolved Solids (TDS), Turbidity, Total Suspended Solids (TSS) and Chemical Oxygen Demand (COD) of groundwater in a closed industrial landfill, subject to the waste discharges of city of Bacau (East Romania), shows that the water quality of the different sampling points is variable. This difference is noted at the level of conductivity, TDS, turbidity, TSS and COD. These differences, however parameters are substantially higher compared the value of the legislation in groundwater Romania. Salinity remains relatively high at the point of sample P1 (0.7). The pH values are comprising in the range of reference values (6.5 to 7.4). The results also showed very strong correlations (r> 0.8) between Conductivity-Salinity, Conductivity -TDS, Salinity, TDS, Turbidity.-TSS, COD and TSS-Turbidity-COD. The strong correlation (0.5 0.8) were noted between Turbidity- Conductivity, Turbidity-Salinity, Turbidity, TDS, TSS conductivity, TSS-Salinity, TSS, TDS, COD, conductivity, salinity, COD, COD-TDS. Principal Component Analysis (PCA) also highlighted groundwater mineralization events of this landfill and possible pollution by organic matter.

The heavy metals contents of the soils, the botanical characteristics and the level of heavy metal accumulation of a closed industrial discharge were examined. The study should evaluate the levels of heavy metal contamination and accumulative potential of the site's plants and assess the feasibility of remediation by these plant species. The results showed high levels of heavy metals (Cr, Ni, Cu, Zn, As, Cd, Pb) in the soil. The botanical study at the dump showed a plant community rich in biodiversity (20 species and 6 families), with no obvious toxicity symptoms. Measurements of metal levels in dominant species confirmed that they were very similar to those reported for species growing in polluted environments. Metals were found in the leaves and roots of plants found on the landfill. However, the bioconcentration factors are less than 1 except for the case of Carduus australis Pomel in Zn which is 1.04. Positive correlations were noted between heavy metal levels in the leaves. Therefore, for effective site restoration, native species may be well suited to cope with local conditions in a phytoextraction strategy.