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AbstractBioenergy projects can lead to direct and indirect land use change (LUC), which can substantially affect greenhouse gas balances with both beneficial and adverse outcomes for bioenergy's contribution to climate change mitigation. The causes behind LUC are multiple, complex, interlinked, and change over time. This makes quantification uncertain and sensitive to many factors that can develop in different directions—including land use productivity, trade patterns, prices and elasticities, and use of by‐products associated with biofuels production. Quantifications reported so far vary substantially and do not support the ranking of bioenergy options with regard to LUC and associated emissions. There are however several options for mitigating these emissions, which can be implemented despite the uncertainties. Long‐rotation forest management is associated with carbon emissions and sequestration that are not in temporal balance with each other and this leads to mitigation trade‐offs between biomass extraction for energy use and the alternative to leave the biomass in the forest. Bioenergy's contribution to climate change mitigation needs to reflect a balance between near‐term targets and the long‐term objective to hold the increase in global temperature below 2°C (Copenhagen Accord). Although emissions from LUC can be significant in some circumstances, the reality of such emissions is not sufficient reason to exclude bioenergy from the list of worthwhile technologies for climate change mitigation. Policy measures to minimize the negative impacts of LUC should be based on a holistic perspective recognizing the multiple drivers and effects of LUC.This article is categorized under: Bioenergy > Economics and Policy Bioenergy > Climate and Environment

In recent years, sustainability concerns have gained increasing attention among countries and stakeholders worldwide. Towards the transition to sustainable rural development, the rural web framework (RWF) has become a consistent tool. Indicators from the RWF have been used to explore sustainable rural development for decision-making tasks, which improves the social, economic, and environmental performance of rural regions. However, the application of the RWF in studies is on the decline. Furthermore, there is a lack of literature reviews on the importance of the RWF and its relationship with different facets of sustainable development. We conducted a systematic literature review (SLR) (a) to explore how studies have used the RWF in the context of sustainable development and (b) to identify areas for further research. This study found that the RWF has mostly been used in developed countries, with fewer applications in developing countries. We suggest that there should be increased application of the RWF, particularly in developing countries, to broaden the rural web–sustainable development discourse and its relevance. This paper presents several areas where the indicators of the RWF can be applied to illustrate their relevance for policy decisions towards the achievement of the sustainable development goals (SDGs).

Short-rotation coppice (SRC) Salix plantations have the potential to provide fast-growing biomass feedstock with significant soil and climate mitigation benefits. Salix varieties exhibit significant variation in their physiological traits, growth patterns and soil ecology—but the effects of these variations have rarely been studied from a systems perspective. This study analyses the influence of variety on soil organic carbon (SOC) dynamics and climate impacts from Salix cultivation for heat production for a Swedish site with specific conditions. Soil carbon modelling was combined with a life cycle assessment (LCA) approach to quantify SOC sequestration and climate impacts over a 50-year period. The analysis used data from a Swedish field trial of six Salix varieties grown under fertilized and unfertilized treatments on Vertic Cambisols during 2001–2018. The Salix systems were compared with a reference case where heat is produced from natural gas and green fallow was the land use alternative. Climate impacts were determined using time-dependent LCA methodology—on a land-use (per hectare) and delivered energy unit (per MJheat) basis. All Salix varieties and treatments increased SOC, but the magnitude depended on the variety. Fertilization led to lower carbon sequestration than the equivalent unfertilized case. There was no clear relationship between biomass yield and SOC increase. In comparison with reference cases, all Salix varieties had significant potential for climate change mitigation. From a land-use perspective, high yield was the most important determining factor, followed by SOC sequestration, therefore high-yielding fertilized varieties such as ‘Tordis’, ‘Tora’ and ‘Björn’ performed best. On an energy-delivered basis, SOC sequestration potential was the determining factor for the climate change mitigation effect, with unfertilized ‘Jorr’ and ‘Loden’ outperforming the other varieties. These results show that Salix variety has a strong influence on SOC sequestration potential, biomass yield, growth pattern, response to fertilization and, ultimately, climate impact.

The feasibility of reliably generating bioenergy from forest biomass waste is intimately linked to supply chain and production processing costs. These costs are, at least in part, directly related to assumptions about the reliability and cost-efficiency of the machinery used along the forestry bioenergy supply chain. Although mechanization in forestry operations has advanced in the last 20 years, it is evident that challenges remain in relation to production capability, standardization of wood quality, and supply guarantee from forestry resources because of the age and reliability of the machinery. An important component in sustainable bioenergy from biomass supply chains will be confidence in consistent production costs linked to guarantees about harvest and haulage machinery reliability. In this context, this paper examines the issue of machinery maintenance and advances in machine learning and big data analysis that are contributing to improved intelligent prediction that is aiding supply chain reliability in bioenergy from woody biomass. The concept of “Industry 4.0” refers to the integration of numerous technologies and business processes that are transforming many aspects of conventional industries. In the realm of machinery maintenance, the dramatic increase in the capacity to dynamically collect, collate, and analyze data inputs including maintenance archive data, sensor-based monitoring, and external environmental and contextual variables. Big data analytics offers the potential to enhance the identification and prediction of maintenance (PdM) requirements. Given that estimates of costs associated with machinery maintenance vary between 20% and 60% of the overall costs, the need to find ways to better mitigate these costs is important. While PdM has been shown to help, it is noticeable that to-date there has been limited assessment of the impacts of external factors such as weather condition, operator experiences and/or operator fatigue on maintenance costs, and in turn the accuracy of maintenance predictions. While some researchers argue these data are captured by sensors on machinery components, this remains to be proven and efforts to enhance weighted calibrations for these external factors may further contribute to improving the prediction accuracy of remaining useful life (RUL) of machinery. This paper reviews and analyzes underlying assumptions embedded in different types of data used in maintenance regimes and assesses their quality and their current utility for predictive maintenance in forestry. The paper also describes an approach to building ‘intelligent’ predictive maintenance for forestry by incorporating external variables data into the computational maintenance model. Based on these insights, the paper presents a model for an intelligent predictive maintenance system (IPdM) for forestry and a method for its implementation and evaluation in the field.

Building facades are under permanent environmental influences, such as sun and acid rain, which age and can ultimately destroy them. Living wall systems can protect facades and offer similar benefits to those gained from installing a green roof. A view back in history shows that vegetated facades are not new technology but can offer multiple benefits as a component of current urban design. In the 19th century, in many European and some North American cities, woody climbers were frequently used as a cover for simple facades. In Central Europe in the 1980s a growing interest in environmental issues resulted in the vision to bring nature into cities. In many German cities incentive programmes were developed, including some that supported tenant initiatives for planting and maintaining climbers in their backyards and facades. Since the 1980s, research has been conducted on issues such as the insulating effects of plants on facades, the ability of plants to mitigate dust, plants’ evaporative cooling effects, and habitat creation for urban wildlife, including birds, spiders and beetles. The aim of this paper is to review research activities on the green wall and facade technology with a focus on Germany. The potential of green facades to improve urban microclimate and buildings’ ecological footprint is high, but they have not developed a widespread presence outside of Germany because they are not as well known as green roofs and there is a lack of implementation guidelines and incentive programs in other countries.

In many parts of the world, climate change has already caused a decline in groundwater recharge, whereas groundwater demand for drinking water production and irrigation continues to increase. In such regions, groundwater tables are steadily declining with major consequences for groundwater-surface water interactions. Predominantly gaining streams that rely on discharge of groundwater from the adjacent aquifer turn into predominantly losing streams whose water seeps into the underground. This reversal of groundwater-surface water interactions is associated with an increase of low river flows, drying of stream beds, and a switch of lotic ecosystems from perennial to intermittent, with consequences for fluvial and groundwater dependent ecosystems. Moreover, water infiltrating from rivers and streams can carry a complex mix of contaminants. Accordingly, the diversity and concentrations of compounds detected in groundwater has been increasing over the past decades. During low flow, stream and river discharge may consist mainly of treated wastewater. In losing stream systems, this contaminated water seeps into the adjoining aquifers. This threatens both ecosystems as well as drinking and irrigation water quality. Climate change is therefore severely altering landscape water balances, with groundwater-surface water-interactions having reached a tipping point in many cases. Current model projections harbor huge uncertainties and scientific evidence for these tipping points remains very limited. In particular, quantitative data on groundwater-surface water-interactions are scarce both on the local and the catchment scale. The result is poor public or political awareness, and appropriate management measures await implementation.

Purpose In Italy, composting olive mill waste has become a common practice, since it mitigates the environmental problems associated with spreading the waste on land. Compost can be used to prepare growth media for plant nursery cultivation as a substitute for peat, a non-renewable resource whose extraction has long raised environmental concerns. Here, we investigate two common composting procedures--open windrow and static-pile in gas-permeable bags--and compare them to evaluate their environmental impact. Methods We perform a cradle-to-grave life cycle assessment (LCA) in accordance with ISO 14040 and 14044. The LCA considers carbon storage in the soil after 100 years, fugitive greenhouse gas (GHG) emissions, and the impacts avoided by substituting for peat. We use cumulative energy demand, global warming potential (GWP), acidification potential, and eutrophication potential indicators in a contribution analysis and explore how the re-use of olive pits for energy production and reduction of commercial fertilizers improves the environmental balance. We also present a scenario analysis that indicates how parameter fluctuations affect the results. Results and discussion Our study shows that peat's impacts can be significantly reduced from 1162.3 to 96.3 kg CO2-eq/Mg for open windrow compost or 43.1 kg CO2-eq/Mg for static-pile compost in gas-permeable bags. For static-pile composting, the lack of volatile organic compound and ammonia emissions and the detection of oxygen concentrations above 12% vol. suggest fully aerobic conditions. Fugitive greenhouse gas emissions were the most important contributions to the GWP. In the contribution analysis for static-pile composting, the avoidance of compost spreading and the carbon storage effect (due to compost usage) contributed 54% of the overall impacts to GWP and between 21 and 45% to the other indicators. Conclusions This LCA study illustrates how horticulturists can improve their resource management practices by recycling olive mill waste materials. Proper management of composting unit aeration can reduce fugitive GHG emissions.

Abstract The impact of wood use by isolated Forest Dependent Communities (FDC) on forest conservation is not well understood. We present a study of wood use in the YUS area (combined watersheds of Yopno, Uruwa and Som rivers) in northern Papua New Guinea, where 57 communities depend on forests for their subsistence. Using a survey methodology based on the Poverty and Environment Network (PEN) survey protocol, we assess the annual volume of wood used, primary sources for this wood and evaluate the capacity of natural forest to sustainably support current rates of wood-use as well as their per capita CO 2 emissions. The primary reason for wood extraction was for fuelwood (6.4 kg person −1 day −1 or ∼11.1 tonne household −1 year −1 ) and housing construction (0.6 m −3 household −1 year −1 ). Fuelwood was collected primarily from areas close to the village, in fallow (grassland) and agroforestry land types, while construction wood was being sourced primarily from secondary and primary forests. The volume of construction wood currently harvested across YUS was approximately 11% the annual increase in timber volumes in available and accessible natural forest. Under this wood use rate and projected population growth (2.5–4%) these communities can harvest construction wood at a sustainable rate for between 55 and 90 years. Nonetheless, we demonstrate that the CO 2 emissions from wood extraction, and in particular fuelwood, are high; approaching 1.15 tonnes CO 2 person −1 year −1 . Household surveys revealed that all smallholders had a strong interest in planting trees for production of wood for house construction, which could reduce pressures on forests and compensate for CO 2 emissions.