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The Coast to Karoo Transect investigates the abundance and diversity of ants and beetles along an altitudinal gradient in the Cederberg mountains of the Western Cape, South Africa. It is a long term project, initiated in 2002 by Prof. S.L. Chown, Stellenbosch University. Data collection is carried out on a biannual (spring and autumn) basis. To monitor changes in invertebrate assemblages, focusing on ants and beetles.

Over half of the world's forests are disturbed, and the rate at which ecosystem processes recover after disturbance is important for the services these forests can provide. We analyze the drivers' underlying changes in rates of key ecosystem processes (biomass productivity, litter productivity, actual litter decomposition, and potential litter decomposition) during secondary succession after shifting cultivation in wet tropical forest of Mexico.We test the importance of three alternative drivers of ecosystem processes: vegetation biomass (vegetation quantity hypothesis), community‐weighted trait mean (mass ratio hypothesis), and functional diversity (niche complementarity hypothesis) using structural equation modeling. This allows us to infer the relative importance of different mechanisms underlying ecosystem process recovery.Ecosystem process rates changed during succession, and the strongest driver was aboveground biomass for each of the processes. Productivity of aboveground stem biomass and leaf litter as well as actual litter decomposition increased with initial standing vegetation biomass, whereas potential litter decomposition decreased with standing biomass. Additionally, biomass productivity was positively affected by community‐weighted mean of specific leaf area, and potential decomposition was positively affected by functional divergence, and negatively by community‐weighted mean of leaf dry matter content.Our empirical results show that functional diversity and community‐weighted means are of secondary importance for explaining changes in ecosystem process rates during tropical forest succession. Instead, simply, the amount of vegetation in a site is the major driver of changes, perhaps because there is a steep biomass buildup during succession that overrides more subtle effects of community functional properties on ecosystem processes. We recommend future studies in the field of biodiversity and ecosystem functioning to separate the effects of vegetation quality (community‐weighted mean trait values and functional diversity) from those of vegetation quantity (biomass) on ecosystem processes and services.

Renewable energy has been prioritized in Danish energy policy since the early 1980s. This has led to the current situation where Denmark is one of the leading countries in the world in the field of wind energy utilization. The background for this success is a story about how a society can manage the development and diffusion of sustainable technologies so that they are simultaneously socially acceptable and environmentally benign. Consequently, this article describes the relationship between the organization of wind power and the protection of nature. The aim is to analyse which kinds of public planning and policy can promote wind power and nature protection in a situation where a conflict exists between these two issues. The discussion acknowledges that it has been a serious problem to balance these contrasting considerations. However, it also suggests that the problems seem solvable if technology development, the social organization relating to the use of the technology and proper planning are brought together to work in a spirit of local involvement. © 1998 John Wiley & Sons, Ltd. and ERP Environment

Green tea catechins mixed with caffeine have been proposed as adjuvants for maintaining or enhancing energy expenditure and for increasing fat oxidation, in the context of prevention and treatment of obesity. These catechins-caffeine mixtures seem to counteract the decrease in metabolic rate that occurs during weight loss. Their effects are of particular importance during weight maintenance after weight loss. Other metabolic targets may be fat absorption and the gut microbiota composition, but these effects still need further investigation in combination with weight loss. Limitations for the effects of green tea catechins are moderating factors such as genetic predisposition related to COMT-activity, habitual caffeine intake, and ingestion combined with dietary protein. In conclusion, a mixture of green tea catechins and caffeine has a beneficial effect on body-weight management, especially by sustained energy expenditure, fat oxidation, and preservation of fat free body-mass, after energy restriction induced body-weight loss, when taking the limitations into account.

In wetlands, a distinct zonation of plant species composition occurs along moisture gradients, due to differential flooding tolerance of the species involved. However, "flooding" comprises two important, distinct stressors (soil oxygen demand [SOD] and partial submergence) that affect plant survival and growth. To investigate how these two flooding stressors affect plant performance, we executed a factorial experiment (water depth x SOD) for six plant species of nutrient-rich and nutrient-poor conditions, occurring along a moisture gradient in Dutch dune slacks. Physiological, growth, and biomass responses to changed oxygen availability were quantified for all species. The responses were consistent with field zonation, but the two stressors affected species differently. Increased SOD increased root oxygen deprivation, as indicated by either raised porosity or increased alcohol dehydrogenase (ADH) activity in roots of flood-intolerant species (Calamagrostis epigejos and Carex arenaria). While SOD affected root functioning, partial submergence tended more to reduce photosynthesis (as shown both by gas exchange and 13C assimilation), leaf dark respiration, 13C partitioning from shoots to roots, and growth of these species. These processes were especially affected if the root oxygen supply was depleted by a combination of flooding and increased SOD. In contrast, the most flood-tolerant species (Juncus subnodulosus and Typha latifolia) were unaffected by any treatment and maintained high internal oxygen concentrations at the shoot : root junction and low root ADH activity in all treatments. For these species, the internal oxygen transport capacity was well in excess of what was needed to maintain aerobic metabolism across all treatments, although there was some evidence for effects of SOD on their nitrogen partitioning (as indicated by 865N values) and photosynthesis. Two species intermediate in flooding tolerance (Carex nigra and Schoenus nigricans) responded more idiosyncratically, with different parameters responding to different treatments. These results show that partial submergence and soil flooding are two very different stressors to which species respond in different ways, and that their effects on physiology, survival, and growth are interactive. Understanding species zonation with water regimes can be improved by a better appreciation of how these factors affect plant metabolism independently and interactively.

Distributed power generation and cogeneration of heat and power is an attractive way toward a more rational conversion of fossil and bio fuels. Solid oxide fuel cell (SOFC) – gas turbine (GT) hybrid systems are emerging as the most promising candidates enabling the achievement of a cleaner and more efficient conversion of a large variety of resources across a broad power range covering from small to medium scale applications. This thesis introduces an innovative concept of SOFC-GT hybrid system that allows reaching efficiencies higher than the state of the art while enabling the carbon dioxide separation and avoiding fuel cell pressurisation technical issues. Several hybrid system design alternatives based on this concept are analysed through a thermodynamic optimisation approach combining process modelling, advanced process integration techniques and multi-objective optimisation. A number of optimal hybrid system configurations are determined for different design targets. The results consistently demonstrate the higher energy conversion performance and flexibility enabled with respect to the state of the art. The innovative concept analysis is extended to two applications for which SOFC-GT hybrid cycles are expected to provide the most significant impact toward sustainability: the small scale distributed generation and the conversion of renewable resources. A simplified version of the new hybrid system layout is especially developed for small scale distributed generation, typical of residential building applications (5-10 kWel). Experimental data are used to prove the technical feasibility of the system and to assess the performance potentially achievable with currently feasible technologies. The results of the analysis underline that energy conversion efficiencies higher than traditional centralised power generation can be achieved even at such a small scale. A systematic process integration and optimisation approach is used to assess the energy conversion performance of the original SOFC-GT hybrid cycle fuelled with hydrothermally gasified wet waste biomass. The analysis highlights the considerable potential of the integrated system that allows for converting wet waste biomass into electricity with First Law efficiency higher than 60% while simultaneously enabling the separation of the biogenic carbon dioxide.

Using 40-year experiment data from a mono-modal rainfall area of northern Togo, we analyzed soil fertility dynamics when 2 and 3-year fallows were alternated with 3-year rotation of groundnut, cotton and sorghum. The control treatment consisted to continuous cultivate the soil in a rotation of groundnut/cotton/sorghum without fallow periods. For each rotation, two fertilisation rates were applied: no fertilisation and mineral fertiliser application during the cropping and/or the fallow periods. Yields of unfertilised crops, which averaged 1 t ha-1 during the first years of cultivation, were often nil in the long-term. In the long-term, yields of fertilised cotton and sorghum decreased by 32 and 50 %, respectively compared to the average of 2.4 and 1.6 t ha-1 obtained during the first decade of cultivation. The long-term decline in crop productivity was mitigated when fallow periods were alternated with cropping periods, and consequently there was partial compensation in terms of production for the unproductive fallowed plots. Long-term yields of fertilised cotton and sorghum in the periodically fallowed plots were 40 and 50 % higher than those in continuously cropped plots, respectively; they were 90 and 60 % higher than those in continuously cropped plots without fertilisation. Like for crop productivity, soil C, N and exchangeable Ca and Mg decreased less in periodically fallowed plots than in continuously cropped plots. The limited soil C decline when fallows were alternated with crops appears to be the consequence of no-tillage period rather than the effect of the highest C inputs to the soil.

Due to the increasing awareness of climate change, depletion of natural resources, and increasing world population, companies in the agri-food sector need to redesign their existing supply chains and take into account both the economic and environmental impact of their operations. In practice not all the required information is available in advance due to various sources of uncertainty in agri-food supply chains. In this research a multi-objective two-stage stochastic programming model is proposed to analyse and evaluate the economic and environmental impacts to account for uncertainty in agri-food supply chains. A mushroom supply chain in the Netherlands is presented as an illustrative case study. Optimal production planning decisions calculated with a two-stage stochastic programming model are compared with the results of an equivalent deterministic model. The results of the optimizations show that accounting for stochasticity in important model parameters can reduce the difference between expected and realized economic performance by approximately 4% on average. Moreover, this paper demonstrates that including stochastic model parameters can reduce the environmental impact without compromising the current economic performance. Given the assumptions in the setup of the case study and the available information, it is concluded that applying a 2-stage stochastic programming approach for production planning decisions can lead to improved economic and environmental performance in an agri-food supply chain. New findings in real-life case studies are needed to get profound insights and understanding on the impact of uncertainty on production planning decisions in sustainable agri-food supply chains.