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[en] Aim of the study: Thinning experiments in Scots pine (Pinus sylvestris L.) stands have been carried out since long in different regions of its distribution. The aim of this paper is to gather the knowledge about the thinning effects on Scots pine stands, from the effects on growth and yield to the provision of ecosystem services in the framework of climate change. Area of study: The review covered studies from different regions of the distribution area of Scots pine Aim of the study: Thinning experiments in Scots pine (Pinus sylvestris L.) stands have been carried out for many years in different regions of its distribution. The aim of this paper is to gather knowledge regarding the effects of thinning on Scots pine stands, from the effects on growth and yield to the provision of ecosystem services in the context of climate change. Area of study: The review covers studies from different regions of the distribution area of Scots pine Material and methods: We reviewed the effect of thinning on four aspects: growth and yield, stability against snow and wind, response to drought, and ecosystem services. Main results: Heavy thinning involves a loss in volume yield, although the magnitude depends on the region, site and stand age. Thinning generally does not affect dominant height while the positive effect on tree diameter depends on the thinning regime. The stability of the stand against snow and wind is lower after the first thinning and increases in the long term. The impact of extreme droughts on tree growth is lower in thinned stands, which is linked to a better capacity to recover after the drought. Thinning generally reduces the wood quality, litter mass, and stand structural diversity, while having neutral or positive effects on other ecosystem services, although these effects can vary depending on the thinning regime. However, scarce information is available for most of the ecosystem services. Research highlight: Existing thinning experiments in Scots pine stands provided valuable information about thinning effects, but new experiments which cover a broad range of ecosystem services under different site conditions are still needed.
[en] Cenovus Energy Inc. is upgrading its natural gas compression facilities at 37 sites it operates in Alberta. The project itself consists of a retrofit of the natural-fas fired engines that power the compressors that fill its natural gas sales pipe-line. Piping to capture fugitive natural gas will also be installed. These emissions will be used as fuel. The efficiency rating of such engine will be the same as a new fuel-injected engine. One of the challenge in the design of the parts of these engines ss to to ensure the least possible downtime to minimize production losses.
[en] Climate change is likely to affect extreme flows as well as average flows. This is an important consideration for hydroelectric power producers. This paper presented the development of an approach to assess the impact of climate changes on seasonal and average annual river flows. The main goal was to investigate how climate change will affect the hydroelectric potential of the Lower Churchill Project using different combinations of emissions scenarios, climate model output and downscaling techniques. The setup and calibration of the numerical hydrological model, WATFLOOD, were performed as preliminary work for the Pinus River basin selected as study basin. Downscaled climate data from the North America change assessment program for both current and future climate periods were analysed. The calibrated model was used to simulate the current and future period streamflow scenarios. The results showed a 13 percent increase in mean annual flows concentrated in the winter and spring seasons.
[en] The potential impacts of climate change on public infrastructure are currently studied to advance planning and prioritization of adaption strategies. This paper investigated the potential vulnerability of the Claireville and G. Ross Lord dams and reservoirs by considering the projected character, its magnitude and its rate of change in future local climatic conditions, the sensitivity of infrastructure to the changes, and the built-in capacity of the infrastructure to absorb any net negative consequence from the predicted changes in climatic conditions. This study used the public infrastructure engineering vulnerability (PIEV) engineering protocol to study the vulnerabilities of both facilities to current climate, as well as future climate change at the 2050 time horizon. Recommendations were provided for actions to be taken to address the potential vulnerabilities that were identified. The project determined that the two dams have the capacity to withstand the existing and projected future climate.
[en] Bruce McGee, adjunct professor at the University of Calgary, Faculty of Chemical and Petroleum Engineering, owns a technology innovation company (E-T Energy Ltd.) and is the inventor of the electro-thermal dynamic stripping (ET-DSP). This technology is in use for the in situ thermal remediation of contaminated soils, with steps towards commercialization in the oil sands now underway. The process consists of injecting electricity instead of steam into the reservoir to mobilize bitumen. The benefit of such a technology less energy and water usage and GHG reductions. Plans are underway to pursue this technology in the heavy oil and tar sands fields of the US.
[en] Some of the commitments made at the Kyoto Conference on the Environment in December 1997 were reviewed. The implication of those promises for the oil industry were assessed, along with speculation as to the means that may be employed to realize the commitments made. The twin concepts of QELRO, (Quantified Emissions Limitation and Reduction Objective) and its relationship to CDM (Clean Development Mechanism), two concepts that grew out of the Kyoto Conference, were also explained. As far as Canada is concerned the commitment is to reduce carbon dioxide emissions to within six per cent of 1990 levels by 2008-2012. Tax reform, tradeable emission credits and joint implementation rules have been briefly examined as possible means the government might use to meet the commitments. Tying the 30 per cent depreciation allowance for manufacturing and processing equipment to some predetermined level of energy efficiency and to introduce tax breaks for investing in companies producing ''biofuels'' such as ethanol made from wood waste, is another option that has been advocated by some. It should be borne in mind that the objective of ecological tax reform is to ''rebalance'' by discouraging non-renewable resources and encouraging renewable ones. With this in mind it is easy to see that it would take only a small shift in emphasis to quickly affect cash flow
[en] Current Progress and Plan of Nuclear Hydrogen Key Technologies Development Project were introduced ·Design and Safety ·Materials and Components ·Fuel Technologies ·Sulfur lodine Hydrogen Production ·H2 System Interfaces, Nuclear Hydrogen, a Practical Success Path to Hydrogen Economy against Climate Changes and Fossil Fuel Exhaustion ·Satisfies Pre requisites to the Hydrogen Economy ·Effective Use of Land for Massive Production of Hydrogen
[en] Ambitious climate change mitigation plans call for a significant increase in the use of renewables, which could, however, make the supply system more vulnerable to climate variability and changes. Here we evaluate climate change impacts on solar photovoltaic (PV) power in Europe using the recent EURO-CORDEX ensemble of high-resolution climate projections together with a PV power production model and assuming a well-developed European PV power fleet. Results indicate that the alteration of solar PV supply by the end of this century compared with the estimations made under current climate conditions should be in the range (-14%;+2%), with the largest decreases in Northern countries. Temporal stability of power generation does not appear as strongly affected in future climate scenarios either, even showing a slight positive trend in Southern countries. Therefore, despite small decreases in production expected in some parts of Europe, climate change is unlikely to threaten the European PV sector. (authors)