Mass-cultivation of carbohydrate rich macroalgae, a possible solution for sustainable biofuel production

Global demand for bio-fuels continues unabated. Rising concerns over environmental pollution and global warming have encouraged the movement to alternate fuels, the world ethanol market is projected to reach 86 billion litres this year. Bioethanol is currently produced from land-based crops such as corn and sugar cane. A continued use of these crops drives the food versus fuel debate. An alternate feed-stock which is abundant and carbohydrate-rich is necessary. The production of such a crop should be sustainable, and, reduce competition with production of food, feed, and industrial crops, and not be dependent on agricultural inputs (pesticides, fertilizer, farmable land, water). Marine biomass could meet these challenges, being an abundant and carbon neutral renewable resource with potential to reduce green house gas (GHG) emissions and the man-made impact on climate change. Here we examine the current cultivation technologies for marine biomass and the environmental and economic aspects of using brown seaweeds for bio-ethanol production.     

Evaluating recycling fertilizers for tomato cultivation in hydroponics,and their impact on greenhouse gas emissions

Soilless culture systems offer an environmentally friendly and resource-efficient alternative to traditional cultivation systems fitting within the scheme of a circular economy. The objective of this research was to examine the sustainable integration of recycling fertilizers in hydroponic cultivation—creating a nutrient cycling concept for horticultural cultivation. Using the nutrient film technique (NFT), three recycling-based fertilizer variants were tested against standard synthetic mineral fertilization as the control, with 11 tomato plants (Solanum lycopersicum L. cv. Pannovy) per replicate (n = 4) and treatment: two nitrified urine-based fertilizers differing in ammonium/nitrate ratio (NH₄⁺:NO₃^?), namely (1) “Aurin” (AUR) and (2) “Crop” (CRO); as well as (3) an organo-mineral mixture of struvite and vinasse (S+V); and (4) a control (NPK). The closed chamber method was adapted for gas fluxes (N₂O, CH₄, and CO₂) from the root zone. There was no indication in differences of the total shoot biomass fresh matter and uptake of N, P and K between recycling fertilizers and the control. Marketable fruit yield was comparable between NPK, CRO and S+V, whereas lower yields occurred in AUR. The higher NH₄⁺:NO₃^? of AUR was associated with an increased susceptibility of blossom-end-rot, likely due to reduced uptake and translocation of Ca. Highest sugar concentration was found in S+V, which may have been influenced by the presence of organic acids in vinasse. N₂O emissions were highest in S+V, which corresponded to our hypothesis that N₂O emissions positively correlate with organic-C input by the fertilizer amendments. Remaining treatments showed barely detectable GHG emissions. A nitrified urine with a low NH₄⁺:NO₃^– (e.g., CRO) has a high potential as recycling fertilizer in NFT systems for tomato cultivation, and S+V proved to supply sufficient P and K for adequate growth and yield. Alternative cultivation strategies may complement the composition of AUR.

     

Assessing the Impact of Areal Precipitation Input on Streamflow Simulations Using the SWAT Model1

Masih Ilyas, Shreedhar Maskey, Stefan Uhlenbrook, and Vladimir Smakhtin, 2011. Assessing the Impact of Areal Precipitation Input on Streamflow Simulations Using the SWAT Model. Journal of the American Water Resources Association (JAWRA) 47(1):179‐195. DOI: 10.1111/j.1752‐1688.2010.00502.x Abstract: Reduction of input uncertainty is a challenge in hydrological modeling. The widely used model Soil Water Assessment Tool (SWAT) uses the data of a precipitation gauge nearest to the centroid of each subcatchment as an input for that subcatchment. This may not represent overall catchment precipitation conditions well. This paper suggests an alternative – using areal precipitation obtained through interpolation. The effectiveness of this alternative is evaluated by comparing its simulations with those based on the standard SWAT precipitation input procedure. The model is applied to mountainous semiarid catchments in the Karkheh River basin, Iran. The model performance is evaluated at daily, monthly, and annual scales by using a number of performance indicators at 15 streamflow gauging stations each draining an area in the range of 590‐42,620 km². The comparison suggests that the use of areal precipitation improves model performance particularly in small subcatchments in the range of 600‐1,600 km². The modified areal precipitation input results in increased reliability of simulated streamflows in the areas of low rain gauge density. Both precipitation input methods result in reasonably good simulations for larger catchments (over 5,000 km²). The use of areal precipitation input improves the accuracy of simulated streamflows with spatial resolution and density of rain gauges having significant impact on results.     

Burial survival of benthic macrofauna following deposition of simulated dredged material

In many coastal regions, the disposal of dredged material constitutes the largest (albeit often localised) anthropogenic disturbance to the seabed. Impacts can be minimised by reducing the amount of sediment overburden on the bed at any one time allowing short-term recovery to proceed via the vertical migration of resident species. However, there is currently a limited understanding of the ability of such species to successfully vertically migrate. This study presents the findings of a field experiment to investigate the vertical migratory capability of temperate macroinvertebrate species following the placement of simulated dredged material. The relationships between vertical migration success with sediment characteristics (organic carbon and sand content) and placement depth were explicitly examined. While the polychaete worms Tharyx sp. A. and Streblospio shrubsolii showed poor vertical migration with only 6 cm of sediment overburden, the oligochaete Tubificoides benedii showed some recovery while the gastropod mollusc Hydrobia ulvae exhibited good migratory success, even with 16 cm of sediment overburden. While increases in sand content from 16% to 38% had no noticeable effect on vertical migration, increased sediment organic content from 0.8% to 3.3% detrimentally affected vertical migratory activity. The results support the theory that species' survival following sediment burial is trophic group-related. The relevance of these findings with respect to dredged material disposal management is discussed.     

Integrating in-situ, Landsat, and MODIS data for mapping in Southern African savannas: experiences of LCCS-based land-cover mapping in the Kalahari in Namibia

Integrated ecosystem assessment initiatives are important steps towards a global biodiversity observing system. Reliable earth observation data are key information for tracking biodiversity change on various scales. Regarding the establishment of standardized environmental observation systems, a key question is: What can be observed on each scale and how can land cover information be transferred? In this study, a land cover map from a dry semi-arid savanna ecosystem in Namibia was obtained based on the UN LCCS, in-situ data, and MODIS and Landsat satellite imagery. In situ botanical relevé samples were used as baseline data for the definition of a standardized LCCS legend. A standard LCCS code for savanna vegetation types is introduced. An object-oriented segmentation of Landsat imagery was used as intermediate stage for downscaling in-situ training data on a coarse MODIS resolution. MODIS time series metrics of the growing season 2004/2005 were used to classify Kalahari vegetation types using a tree-based ensemble classifier (Random Forest). The prevailing Kalahari vegetation types based on LCCS was open broadleaved deciduous shrubland with an herbaceous layer which differs from the class assignments of the global and regional land-cover maps. The separability analysis based on Bhattacharya distance measurements applied on two LCCS levels indicated a relationship of spectral mapping dependencies of annual MODIS time series features due to the thematic detail of the classification scheme. The analysis of LCCS classifiers showed an increased significance of life-form composition and soil conditions to the mapping accuracy. An overall accuracy of 92.48% was achieved. Woody plant associations proved to be most stable due to small omission and commission errors. The case study comprised a first suitability assessment of the LCCS classifier approach for a southern African savanna ecosystem.     

Human Adaptation to Work in Two Different Climates

The processes of acclimation to hot-dry and to warm-humid climates were studied using two approaches: a quantitative analysis of literature data and an experimental study in the laboratory concerning the physiological parameters of heart rate, rectal temperature, sweat loss, and subjective assessment.

Analysis o f literature data: Data from 62 experiments with a total of 813 participants were pooled and recalculated. The experiments ranged from 6 to 24 days, air temperatures from 30.4 to 50.0°C, water vapor pressures from 1.5 to 6.5 kPa, and wet bulb globe temperatures (WBGT) from 27.4 to 38.6°C.

Laboratory studies: In the laboratory, 8 participants were acclimated during 15 consecutive days to a hot-dry climate and to a warm-humid climate, which were equivalent in terms of the WBGT (33.5 and 33.6°C, respectively). The participants walked four times for 25 min on a treadmill at a speed of 4 km/h. The hot-dry climate caused somewhat greater strain than the warm-humid condition. In the course of acclimation to the hot-dry climate, heart rate and rectal temperature started at higher levels, decreased slightly steeper but remained on a higher level throughout. Nevertheless, the differences between both thermal conditions were small, and both physiologic functions reached the point of acclimation almost at the same time under warm-humid and under hot-dry exposure. Sweat loss, which is not regarded as a valid predictor for acclimation, was considerably higher but increased less in the hot-dry than in the warm-humid climate.     

Impact Resistance of Materials for Guards on Cutting Machine Tools—Requirements in Future European Safety Standards

Guards on machine tools are meant to protect operators from injuries caused by tools, workpieces, and fragments hurled out of the machine’s working zone. This article presents the impact resistance requirements, which guards according to European safety standards for machine tools must satisfy. Based upon these standards the impact resistance of different guard materials was determined using cylindrical steel projectiles. Polycarbonate proves to be a suitable material for vision panels because of its high energy absorption capacity. The impact resistance of 8-mm thick polycarbonate is roughly equal to that of a 3-mm thick steel sheet Fe P01. The limited ageing stability, however, makes it necessary to protect poycarbonate against cooling lubricants by means of additional panes on both sides.     

Small Female Upper Extremity Interaction with a Deploying Side Air Bag

This paper presents a study characterizing the interaction between a deploying side air bag and a small female upper extremity. The results are based on twelve tests with small female cadavers, and fifteen tests with the instrumented SAE 5th percentile female upper extremity attached to the 5th percentile Hybrid III female dummy. The upper extremity was loaded by a deploying seat mounted thoracic side air bag in a static test environment. Three inflators were used that varied in peak pressure and pressure onset rate. Despite kinematic differences between the dummy and cadaver, the moments recorded in the cadaver and dummy were similar. Chondral and osteochondral fractures in the cadaver elbow joints were identified in seven of the twelve cadaver tests, while a simple fracture of the distal humerus head was observed in one test. A linear logistic regression analysis was performed to correlate occurrence of recorded injury and the test parameters. Injury risk functions were constructed using age, forearm acceleration, elbow moment, and air bag inflator level as variables.