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Upwelling processes bring nutrient-rich waters from the deep ocean to the surface. Areas of upwelling are often associated with high productivity, offering great economic value in terms of fisheries. The sensitivity of spring/summer-time coastal upwelling systems to climate change has recently received a lot of attention. Several studies have suggested that their intensity may increase in the future while other authors have shown decreasing intensity in their equatorward portions. Yet, recent observations do not show robust evidence of this intensification. The Senegalo-Mauritanian upwelling system (SMUS) located at the southern edge of the north Atlantic system (12°N–20°N) and most active in winter/spring has been largely excluded from these studies. Here, the seasonal cycle of the SMUS and its response to climate change is investigated in the database of the Coupled Models Inter comparison Project Phase 5 (CMIP5). Upwelling magnitude and surface signature are characterized by several sea surface temperature and wind stress indices. We highlight the ability of the climate models to reproduce the system, as well as their biases. The simulations suggest that the intensity of the SMUS winter/spring upwelling will moderately decrease in the future, primarily because of a reduction of the wind forcing linked to a northward shift of Azores anticyclone and a more regional modulation of the low pressures found over Northwest Africa. The implications of such an upwelling reduction on the ecosystems and local communities exploiting them remains very uncertain.

We utilize a variety of climate datasets to examine impacts of two mechanisms on precipitation in the Greater Horn of Africa (GHA) during northern-hemisphere summer. First, surface-pressure gradients draw moist air toward the GHA from the tropical Atlantic Ocean and Congo Basin. Variability of the strength of these gradients strongly influences GHA precipitation totals and accounts for important phenomena such as the 1960s–1980s rainfall decline and devastating 1984 drought. Following the 1980s, precipitation variability became increasingly influenced by the southern tropical Indian Ocean (STIO) region. Within this region, increases in sea-surface temperature, evaporation, and precipitation are linked with increased exports of dry mid-tropospheric air from the STIO region toward the GHA. Convergence of dry air above the GHA reduces local convection and precipitation. It also produces a clockwise circulation response near the ground that reduces moisture transports from the Congo Basin. Because precipitation originating in the Congo Basin has a unique isotopic signature, records of moisture transports from the Congo Basin may be preserved in the isotopic composition of annual tree rings in the Ethiopian Highlands. A negative trend in tree-ring oxygen-18 during the past half century suggests a decline in the proportion of precipitation originating from the Congo Basin. This trend may not be part of a natural cycle that will soon rebound because climate models characterize Indian Ocean warming as a principal signature of greenhouse-gas induced climate change. We therefore expect surface warming in the STIO region to continue to negatively impact GHA precipitation during northern-hemisphere summer.

Abstract Worldwide the search for new raw materials that are suitable for the production of energy pellets is increasing. Each new raw material undergoes evaluation through various analytical processes and quality assessments before being considered for use as energy pellet. In recent times, the raw materials such as agricultural, forestry, and food waste, as well as the surpluses originating from the agri-food production have become very popular for the production of energy pellets. In this study, we evaluated the feasibility of using lignocellulosic raw materials such as chamomile waste, birch sawdust, pea waste, and soybean waste for the production of pellets. In this study, we focused on the production of thermal energy from pellets by assessing the pellets in accordance with the required standards. The results have shown that lignocellulosic raw materials can be used to produce good quality energy pellets. The proportion of individual raw materials determines the individual strength characteristics of pellets and the suitability of pellets to produce thermal energy.

Abstract The innovation of this research was a holistic approach to the problem of linking the biometric characteristics of six energy plants species and the distribution of moisture along the shoot‘ height and determination of linear models of particle sizes in relation to the moisture. The median biometric parameters values for growth phases I and II were as follows: shoot weight: 63 g and 65 g; stalk weight: 45.1 g and 43.8 g; plant length: 1273 mm and 2157 mm; shoot centre of gravity: 698 mm and 968 mm; slenderness ratio 147 and 215, respectively. For big bluestem and Spartina pectinata the largest values were for slenderness ratio and for phase II amounted to 403 and 410, respectively but most other parameters were the smallest values. Regarding the shoots’ growth, the greatest influence was on the stalks by increasing their lengths more than their diameters. The highest difference in the plant length between harvest terms was observed for Spartina pectinata which increased from 793 mm to 2257 mm (by 185%). The lengths of the Jerusalem artichoke, miscanthus and big bluestem plants also significantly increased: from 1345 mm to 2920 mm (117%), 1214 mm to 2065 mm (70%) and 1064 mm to 1779 mm (67%), respectively. Positive correlation coefficient values between parameters (shoot weight, leaf weight, stalk weight and plant length) indicate that to characterize of plant shoots the shoot mass and plant slenderness could be used. The Rosin-Rammler function fit the chopped plan material size distribution data with an R 2 = 0.909–0.991. All the biomass particle sizes belonged to the “very poorly sorted” category (2.00 mm ≤ σ ig ≤ 4.00 mm), and the particle size distributions were “fine skewed” (0.1 ≤ GS is ≤ 0.3) and “mesokurtic” (0.90 ≤ K gs ≤ 1.11). For grasses relation of particle sizes vs. moisture for phase II (August for Spartina and big bluestem or October for miscanthus) was inverted to phase I (June) with slope coefficients −0.11 and 0.09, respectively. For leaf plants direction of the relation was preserved, wherein for phase II (all plants harvested in October) the growth dynamic was lower than for phase I and slope coefficients of the lines were 0.17 and 0.04, respectively. Moisture content of leafy plants was high, and its distribution along the shoots’ heights was different than that for grasses. Varied values of particle size and weight of plant components, together with the change in moisture along the height of the plants, will impact the diversity of the dynamic loads of elements and working units of forage harvesters and can be useful to explain these results.

Biomass pre-treatment is a key step in achieving the economic competitiveness of biomass conversion. In the present work, an imidazole pre-treatment process was performed and evaluated using wheat straw and eucalyptus residues as model feedstocks for agriculture and forest-origin biomasses, respectively. Results showed that imidazole is an efficient pre-treatment agent; however, better results were obtained for wheat straw due to the recalcitrant behavior of eucalyptus residues. The temperature had a stronger effect than time on wheat straw pre-treatment but at 160 °C and 4 h, similar results were obtained for cellulose and hemicellulose content from both biomasses (ca. 54% and 24%, respectively). Lignin content in the pre-treated solid was higher for eucalyptus residues (16% vs. 4%), as expected. Enzymatic hydrolysis, applied to both biomasses after different pre-treatments, revealed that results improved with increasing temperature/time for wheat straw. However, these conditions had no influence on the results for eucalyptus residues, with very low glucan to glucose enzymatic hydrolysis yield (93% for wheat straw vs. 40% for eucalyptus residues). Imidazole can therefore be considered as a suitable solvent for herbaceous biomass pre-treatment.

The biotechnological development has traditionally focused on the compliance with regulatory demands rather than optimising the processes or analysing their sustainability. This work proposes the combination of available tools for the comprehensive sustainability assessment of a blue biotechnology process based on the cultivation of the microalgae Haematococcus pluvialis. The work aims to include environmental, economic and social dimensions to measure the sustainability of the production of a carotenoid with potential applications in food, nutraceutical, cosmetics and eventually pharmaceutical industries. Electricity for cultivation was identified as the major contributor to the environmental impacts, which depended significantly on the production scale. Social benefits were mainly related to workers and consumers, while the economic assessment suggested a profitable process with a relatively short period to recover the initial investment.

Development and implementation of the agri-environmental program is mandatory for each member state of the European Union. Polish agri-environmental program focuses not only on extensification of agricultural production but also at sustaining of existing Europe’s largest biodiversity in the rural areas. The agri-environmental program is an alternative to the conventional agriculture and is designed to encourage farmers to adopt practices that lead to the greening of agricultural production and is contributes to the retardation of intensive transforming of habitats in rural areas. Agricultural producers in the Podkarpackie voivodeship are seeking new opportunities and they see a chance for the development of their farms also in agri-environmental program. Survey research has shown that the majority of the farmers decided to participate in the agri-environmental actions for economic reasons and in the extent of their knowledge and the way in which they perceive environmental issues do not differ much from the surveyed parties who do not carry out agrienvironmental program. Even thought they composted organic waste, do not dispose them in the illegal dumpsites and they claim (98%) that they comply with the Code of Good Agricultural Practice (while in the group who do not realize the program that answer was provided only by 20% of the respondents), they did not recognize the threat to the environment due to the deterioration of biodiversity.