First process-based simulations of climate change impacts on global tea production indicate large effects in the World’s major producer countries

Modeling of climate change impacts have mainly been focused on a small number of annual staple crops that provide most of the world's calories. Crop models typically do not represent perennial crops despite their high economic, nutritional, or cultural value. Here we assess climate change impacts on global tea production, chosen because of its high importance in culture and livelihoods of people around the world. We extended the dynamic global vegetation model with managed land, LPJmL4, global crop model to simulate the cultivation of tea plants. Simulated tea yields were validated and found in good agreement with historical observations as well as experiments on the effects of increasing CO2 concentrations. We then projected yields into the future under a range of climate scenarios from the Inter-Sectoral Impact Model Intercomparison Project. Under current irrigation levels and lowest climate change scenarios, tea yields are expected to decrease in major producing countries. In most climate scenarios, we project that tea yields are set to increase in China, India, and Vietnam. However, yield losses are expected to affect Kenya, Indonesia, and Sri Lanka. If abundant water supply and full irrigation is assumed for all tea cultivation areas, yields are projected to increase in all regions

Resource use in a low-input organic vegetable food supply system in UK - a case study

Use of local renewable resources in a low-input organic vegetable food supply system in UK is evaluated against the use of imported resources in the same system. Despite much focus by the farmer on low-input, the production and distribution system is only supported by 13% local renewable resources based on an emergy assessment. Future sustainability of such systems are discussed

Fast Track Integration of Computational Methods with Experiments in Small Wind Turbine Development

In general, standard aerodynamic design is divided into two paths—numerical analysis and empirical tests. It is crucial to efficiently combine both approaches in order to entirely fulfill the requirements of the design process as well as the final product. An effective use of computational analysis is a challenge, however it can significantly improve understanding, exploring and confining the search for optimal product solutions. The article focuses on a rapid prototyping and testing procedure proposed and employed at the Institute of Turbomachinery, Lodz University of Technology (IMP TUL). This so called Fast Track approach combines preparation of numerical models of a wind turbine rotor, manufacturing of its geometry by means of a 3D printing method and testing it in an in-house wind tunnel. The idea is to perform the entire procedure in 24 h. The proposed process allows one to determine the most auspicious sets of rotor blades within a short time. Owing to this, it significantly reduces the amount of individual subsequent examinations. Having fixed the initial procedure, it is possible to expand research on the singled-out geometries. The abovementioned observations and the presented overview of the literature on uses of 3D printing in aerodynamic testing prove rapid prototyping as an innovative and widely-applicable method, significantly changing our approach to experimental aerodynamics

Experimental Investigation of the Cooperation of Wind Turbines

The article discusses the wind tunnel experimental investigation of two turbines (the downstream unit placed fully in the wake of the upstream one) at various turbulence intensity levels and wind turbine separation distances, at a Reynolds number of approximately 105. The velocity deficit due to the upstream turbine operation is reduced as the wake mixes with the undisturbed flow, which may be enhanced by increasing the turbulence intensity. In a natural environment, this may be provoked by natural wind gusts or changes in the wind inflow conditions. Increased levels of turbulence intensity enlarge the plateau of optimum wind turbine operation—this results in the turbine performance being less prone to variations of tip speed ratio. Another important set of results quantifies the influence of the upstream turbine operation at non-optimal tip speed ratio on the overall system performance, as the downstream machine gains more energy from the wake flow. Thus, all power output maximisation analyses of wind turbine layout in a cluster should encompass not only the locations and distances between the units, but also their operating parameters (TSR, but also pitch or yaw control of the upstream turbine(s))

How Eco-Efficient Are Low-Input Cropping Systems in Western Europe, and What Can Be Done to Improve Their Eco-Efficiency

Low-input cropping systems were introduced in Western Europe to reduce the environmental impacts of intensive farming, but some of their benefits are offset by lower yields. In this paper, we review studies that used Life Cycle Assessment (LCA) to investigate the effects of reducing external inputs on the eco-efficiency of cropping systems, measured as the ratio of production to environmental impacts. We also review various cropping system interventions that can improve this ratio. Depending on the initial situation and the impacts considered, reducing inputs will in itself either reduce or increase environmental impacts per product unit—highly eco-efficient cropping systems require application of optimum instead of minimum quantities of external inputs. These optimum rates can be lowered by utilizing positive synergies between crops to minimise waste of nutrients and water and by utilizing locally produced organic waste; both from within the farm as well as well as from the surrounding sociotechnical environment. Eco-efficiency can also be improved by increasing yields in a sustainable matter. Strategies such as breeding, increasing diversity, no-tillage or intercropping will not be effective under all conditions. LCA provides a useful framework to identify environmentally optimum levels of inputs and trade-offs between various intensification scenarios.ISSN:2071-105

Life cycle assessment of bread from several alternative food networks in Europe

In this study, we used LCA to test the influence of practicing low-input farming, on-farm processing and direct distribution on the environmental impact of bread consumption. Primary data were collected from four commercially active producers (two in France, one in Italy and one in Portugal) who cultivate cereals under low levels of inputs, process grains on farm and distribute their products directly to end consumers. Environmental impacts of products were compared to equivalents from supermarkets, characterised by higher rates of applied inputs at the agricultural stage, industrial processing and centralised distribution. The scope of LCA was from cradle to the consumer. The study revealed a high variability of results between individual cases. At the agricultural stage, products from a low-input cropping system integrated with livestock production in France and from a small-scale labour intensive production in Portugal showed similar or better performance on most impact categories to those from high-input agriculture, while horse farming in France and a stockless cultivation of ancient wheat cultivars in Italy revealed mostly higher environmental burdens. Decentralised processing and distribution in France had similar or slightly higher impacts to conventional supply chains, while Italian and Portuguese cases revealed clearly higher environmental burdens for most impact categories. Results demonstrate that while there might be a positive relationship between the scale and eco-efficiency of processing and distribution, the level of agricultural inputs, yields and transport distances cannot be used as proxies of environmental performance. Products of low-input systems can have much higher, similar or lower impacts to their high-input counterparts due to the influence of site conditions and the management. More research assessing the effectiveness of context-specific management systems is needed as oppose to the generic comparisons between labelling schemes (i.e. organic and conventional farming). (C) 2014 Elsevier Ltd. All rights reserved

CO2 fertilization effect may balance climate change impacts on oil palm cultivation

Oil palm cultivation has become one of the world’s most important drivers of land use change in the tropics causing biodiversity loss and greenhouse gas emissions. The impact of climate change and rising carbon dioxide (CO _2 ) concentrations in the atmosphere on oil palm productivity is not well understood. If environmental change leads to declining palm oil yields in existing cultivation areas, cultivation areas may expand or shift to other regions. Here we assess climate change impacts on palm oil production using an extended version of the dynamic global vegetation model with managed land, LPJmL4, and a range of climate scenarios from the inter-sectoral impact model intercomparison project. We find increasing average yields under all future climate scenarios. This contradicts earlier studies, which did not consider the potential positive effect of CO _2 fertilization. If we do not account for CO _2 fertilization, future yields also decrease in our simulations. Our results indicate the potentially large role of rising CO _2 levels on oil palm cultivation. This highlights the importance of further applied plant science to better understand the impact of climate change and elevated CO _2 levels on oil palm growth and productivity

Extremely low frequency electromagnetic field measurements at the Hylaty station and methodology of signal analysis

We present the Hylaty geophysical station, a high-sensitivity and low-noise facility for extremely low frequency (ELF, 0.03–300 Hz) electromagnetic field measurements, which enables a variety of geophysical and climatological research related to atmospheric, ionospheric, magnetospheric, and space weather physics. The first systematic observations of ELF electromagnetic fields at the Jagiellonian University were undertaken in 1994. At the beginning the measurements were carried out sporadically, during expeditions to sparsely populated areas of the Bieszczady Mountains in the southeast of Poland. In 2004, an automatic Hylaty ELF station was built there, in a very low electromagnetic noise environment, which enabled continuous recording of the magnetic field components of the ELF electromagnetic field in the frequency range below 60 Hz. In 2013, after 8 years of successful operation, the station was upgraded by extending its frequency range up to 300 Hz. In this paper we show the station's technical setup, and how it has changed over the years. We discuss the design of ELF equipment, including antennas, receivers, the time control circuit, and power supply, as well as antenna and receiver calibration. We also discuss the methodology we developed for observations of the Schumann resonance and wideband observations of ELF field pulses. We provide examples of various kinds of signals recorded at the station