Sustainability

2153 KiB

Open AccessArticle

2D Versus 3D: The Relevance of the Mode of Presentation for the Economic Valuation of an Alpine Landscape

by Michael Getzner, Barbara Färber and Claudia Yamu

Sustainability 2016, 8(6), 591; https://doi.org/10.3390/su8060591 - 22 Jun 2016

Cited by 12 | Viewed by 6162

In order to value the transformation of landscapes from an economic perspective, survey respondents are usually presented with pictures of various landscapes with the aim to visualize differences in their appearance. The current paper presents a classroom experiment ascertaining differences, and potential advantages [...] Read more.

In order to value the transformation of landscapes from an economic perspective, survey respondents are usually presented with pictures of various landscapes with the aim to visualize differences in their appearance. The current paper presents a classroom experiment ascertaining differences, and potential advantages and disadvantages, of 2D versus 3D (stereoscopic) presentations of landscape changes. The landscape to be valued was a traditional Alpine pasture in the Austrian Alps as a prominent example of natural and cultural heritage (traditional economy and specific ecology). Two alternative scenarios included, on the one hand, changes in agricultural uses, leading to natural afforestation (reforestation) and decay of existing infrastructure (e.g., hiking trails). On the other hand, significantly extended tourism infrastructure (e.g., new attractions for visitors) was presented. Two groups were presented manipulated pictures (2D/non-stereoscopic), and 3D (stereoscopic) presentations with 3D glasses, respectively. Both groups were then asked for their perception of landscape changes. It turns out that significant differences between the two groups could be detected in terms of the frequency of vacations at Alpine pastures. For instance, respondents in the 3D stereoscopic group stated a significantly higher frequency of trips. However, on the other hand, they did not state a significantly different willingness-to-pay to prevent landscape changes disadvantageous in terms of sustainability. The study results thus suggest that the mode of presentation may affect the valuation of landscape changes depending on the valuation instrument. Full article

(This article belongs to the Special Issue Sustainability of Cultural and Natural Heritage)

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2391 KiB

Open AccessArticle

Study on Solar Radiation Models in South Korea for Improving Office Building Energy Performance Analysis

by Kee Han Kim, John Kie-Whan Oh and WoonSeong Jeong

Sustainability 2016, 8(6), 589; https://doi.org/10.3390/su8060589 - 22 Jun 2016

Cited by 19 | Viewed by 7315

Abstract

Hourly global solar radiation in a weather file is one of the significant parameters for improving building energy performance analyses using simulation programs. However, most weather stations worldwide are not equipped with solar radiation sensors because they tend to be difficult to manage. [...] Read more.

Hourly global solar radiation in a weather file is one of the significant parameters for improving building energy performance analyses using simulation programs. However, most weather stations worldwide are not equipped with solar radiation sensors because they tend to be difficult to manage. In South Korea, only twenty-two out of ninety-two weather stations are equipped with sensors, and there are large areas not equipped with any sensors. Thus, solar radiation must often be calculated by reliable solar models. Hence, it is important to find a reliable model that can be applied in the wide variety of weather conditions seen in South Korea. In this study, solar radiation in the southeastern part of South Korea was calculated using three solar models: cloud-cover radiation model (CRM), Zhang and Huang model (ZHM), and meteorological radiation model (MRM). These values were then compared to measured solar radiation data. After that, the calculated solar radiation data from the three solar models were used in a building energy simulation for an office building with various window characteristics conditions, in order to identify how solar radiation differences affect building energy performance. It was found that a seasonal solar model for the area should be developed to improve building energy performance analysis. Full article

(This article belongs to the Section Sustainable Engineering and Science)

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1564 KiB

Open AccessReview

Vulnerability Assessment Models to Drought: Toward a Conceptual Framework

by Kiumars Zarafshani, Lida Sharafi, Hossein Azadi and Steven Van Passel

Sustainability 2016, 8(6), 588; https://doi.org/10.3390/su8060588 - 22 Jun 2016

Cited by 55 | Viewed by 16039

Abstract

Drought is regarded as a slow-onset natural disaster that causes inevitable damage to water resources and to farm life. Currently, crisis management is the basis of drought mitigation plans, however, thus far studies indicate that effective drought management strategies are based on risk [...] Read more.

Drought is regarded as a slow-onset natural disaster that causes inevitable damage to water resources and to farm life. Currently, crisis management is the basis of drought mitigation plans, however, thus far studies indicate that effective drought management strategies are based on risk management. As a primary tool in mitigating the impact of drought, vulnerability assessment can be used as a benchmark in drought mitigation plans and to enhance farmers’ ability to cope with drought. Moreover, literature pertaining to drought has focused extensively on its impact, only awarding limited attention to vulnerability assessment as a tool. Therefore, the main purpose of this paper is to develop a conceptual framework for designing a vulnerability model in order to assess farmers’ level of vulnerability before, during and after the onset of drought. Use of this developed drought vulnerability model would aid disaster relief workers by enhancing the adaptive capacity of farmers when facing the impacts of drought. The paper starts with the definition of vulnerability and outlines different frameworks on vulnerability developed thus far. It then identifies various approaches of vulnerability assessment and finally offers the most appropriate model. The paper concludes that the introduced model can guide drought mitigation programs in countries that are impacted the most by drought. Full article

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427 KiB

Open AccessArticle

Evaluation of Sustainable Development of Resources-Based Cities in Shanxi Province Based on Unascertained Measure

by Yong-Zhi Chang and Suo-Cheng Dong

Sustainability 2016, 8(6), 585; https://doi.org/10.3390/su8060585 - 22 Jun 2016

Cited by 28 | Viewed by 4715

Abstract

An index system is established for evaluating the level of sustainable development of resources-based cities, and each index is calculated based on the unascertained measure model for 11 resources-based cities in Shanxi Province in 2013 from three aspects; namely, economic, social, and resources [...] Read more.

An index system is established for evaluating the level of sustainable development of resources-based cities, and each index is calculated based on the unascertained measure model for 11 resources-based cities in Shanxi Province in 2013 from three aspects; namely, economic, social, and resources and environment. The result shows that Taiyuan City enjoys a high level of sustainable development and integrated development of economy, society, and resources and environment. Shuozhou, Changzhi, and Jincheng have basically realized sustainable development. However, Yangquan, Linfen, Lvliang, Datong, Jinzhong, Xinzhou and Yuncheng have a low level of sustainable development and urgently require a transition. Finally, for different cities, we propose different countermeasures to improve the level of sustainable development. Full article

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563 KiB

Open AccessShort Note

The Rise of the Food Risk Society and the Changing Nature of the Technological Treadmill

by Lioudmila Chatalova, Daniel Müller, Vladislav Valentinov and Alfons Balmann

Sustainability 2016, 8(6), 584; https://doi.org/10.3390/su8060584 - 22 Jun 2016

Cited by 11 | Viewed by 8719

Abstract

Economic development of transition and developed countries is associated with increasingly unhealthy dietary habits among low-income population segments. Drawing on Ulrich Beck’s sociological theory of risk society, the present research note calls attention to the positive relation between national economic development and food [...] Read more.

Economic development of transition and developed countries is associated with increasingly unhealthy dietary habits among low-income population segments. Drawing on Ulrich Beck’s sociological theory of risk society, the present research note calls attention to the positive relation between national economic development and food risks that result in the rise of food-related diseases and healthcare costs. On this basis, we argue that the knowledge-intensive agribusiness may translate Cochrane’s technological treadmill into Beck’s risk treadmill that shifts a growing share of food-related healthcare costs from producers toward consumers, state, and the healthcare system. This argument motivates a novel research program dealing with the “food risk treadmill” that emerges in response to modern farming and agribusiness practices. Awareness of the food risk treadmill may help to streamline the development of agricultural science and to prevent it from being excessively dominated by the agricultural and food industry. Full article

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Open AccessArticle

Environmental Impact Analysis of Acidification and Eutrophication Due to Emissions from the Production of Concrete

by Tae Hyoung Kim and Chang U Chae

Sustainability 2016, 8(6), 578; https://doi.org/10.3390/su8060578 - 22 Jun 2016

Cited by 87 | Viewed by 11658

Abstract

Concrete is a major material used in the construction industry that emits a large amount of substances with environmental impacts during its life cycle. Accordingly, technologies for the reduction in and assessment of the environmental impact of concrete from the perspective of a [...] Read more.

Concrete is a major material used in the construction industry that emits a large amount of substances with environmental impacts during its life cycle. Accordingly, technologies for the reduction in and assessment of the environmental impact of concrete from the perspective of a life cycle assessment (LCA) must be developed. At present, the studies on LCA in relation to greenhouse gas emission from concrete are being carried out globally as a countermeasure against climate change. However, the studies on the impact of the substances emitted in the concrete production process on acidification and eutrophication are insufficient. As such, assessing only a single category of environmental impact may cause a misunderstanding about the environmental friendliness of concrete. The substances emitted in the concrete production process have an impact not only on global warming but also on acidification and eutrophication. Acidification and eutrophication are the main causes of air pollution, forest destruction, red tide phenomena, and deterioration of reinforced concrete structures. For this reason, the main substances among those emitted in the concrete production process that have an impact on acidification and eutrophication were deduced. In addition, an LCA technique through which to determine the major emissions from concrete was proposed and a case analysis was carried out. The substances among those emitted in the concrete production process that are related to eutrophication were deduced to be NO_x, NH₃, NH₄⁺, COD, NO₃⁻, and PO₄³⁻. The substances among those emitted in the concrete production process that are related to acidification, were found to be NO_x, SO₂, H₂S, and H₂SO₄. The materials and energy sources among those input into the concrete production process, which have the biggest impact on acidification and eutrophication, were found to be coarse aggregate and fine aggregate. Full article

(This article belongs to the Special Issue Life Cycle Assessment on Green Building Implementation)

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4271 KiB

Open AccessArticle

Timber Chips as the Insulation Material for Energy Saving in Prefabricated Offices

by Yupeng Wang and Hiroatsu Fukuda

Sustainability 2016, 8(6), 587; https://doi.org/10.3390/su8060587 - 21 Jun 2016

Cited by 3 | Viewed by 5003

Abstract

This research demonstrates the feasibility of a roof insulation method for prefabricated offices that uses vinyl packed timber chips to reduce air conditioning loads (hereinafter referred to as AC loads) and which also improves indoor thermal comfort. The advantages of the new roof [...] Read more.

This research demonstrates the feasibility of a roof insulation method for prefabricated offices that uses vinyl packed timber chips to reduce air conditioning loads (hereinafter referred to as AC loads) and which also improves indoor thermal comfort. The advantages of the new roof insulation method were revealed through comparing the impacts of four roof types on prefabricated offices. The AC load and indoor thermal comfort (surface temperature and air temperature) were evaluated. The disposal of scrap timber discarded from building construction projects is costing money, and is also a waste of natural resources. The assessment of a new roof insulation method with timber chips demonstrates the advanced usage of timber chips, reducing the environmental load in the building construction process. On the other hand, since prefabricated offices have lower thermal storage capacities and are less airtight than RC (reinforced concrete) or S (steel) structured buildings, the AC load consumption and indoor thermal comfort exacerbation in prefabricated offices is more serious. Especially in summer, a large amount of solar energy absorption from the roof raises the indoor air temperature and significantly increases the cooling load. This research contributes to the environmental design for prefabricated offices, and develops a method for the reuse of wood chips. Full article

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434 KiB

Open AccessArticle

Covering Indirect Emissions Mitigates Market Power in Carbon Markets: The Case of South Korea

by Sunghee Shim and Jiwoong Lee

Sustainability 2016, 8(6), 583; https://doi.org/10.3390/su8060583 - 21 Jun 2016

Cited by 5 | Viewed by 4763

Abstract

One of the main concerns of policymakers regarding emissions trading markets is that some firms may well enjoy market power owing to their share of the emissions. This study shows that including indirect emissions within the coverage of an emissions trading scheme can [...] Read more.

One of the main concerns of policymakers regarding emissions trading markets is that some firms may well enjoy market power owing to their share of the emissions. This study shows that including indirect emissions within the coverage of an emissions trading scheme can help to reduce market power and thereby enhance social efficiency. In this study, the market concentration measured by the Herfindahl-Hirschman Index significantly drops after including indirect emissions in the South Korean emissions trading market. In addition, other market concentration measures are also considered to verify that the conclusion does not depend on the choice of concentration measures. Full article

(This article belongs to the Section Economic and Business Aspects of Sustainability)

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6446 KiB

Open AccessArticle

Coordinated Development Analysis of the “Resources-Environment-Ecology-Economy-Society” Complex System in China

by Mingxia Xie, Jiayao Wang and Ke Chen

Sustainability 2016, 8(6), 582; https://doi.org/10.3390/su8060582 - 21 Jun 2016

Cited by 32 | Viewed by 7762

Abstract

The aim of investigating the coordination of the complex system constituted by resources, environment, ecology, economy and society subsystems (CSR3ES), is to achieve sustainable development by: (1) describing the complicated relationships of the inner-subsystems and inter-systems; (2) designing the calculation method of the [...] Read more.

The aim of investigating the coordination of the complex system constituted by resources, environment, ecology, economy and society subsystems (CSR3ES), is to achieve sustainable development by: (1) describing the complicated relationships of the inner-subsystems and inter-systems; (2) designing the calculation method of the coordination degree for CSR3ES; (3) analyzing its developing trends from a macro point of view through comprehensive coordination degree; and (4) to determine the direction of system restoration from a micro point of view based on the inner-subsystem and inter-subsystem coordination degree, and to develop specific improvement strategies. By setting a province-level administrative region as a decision-making unit (DMU), the nationwide coordination of CSR3ES was studied. The main conclusions are: (1) The coordination degree between the subsystems is directly influenced by interactions between the elements. (2) Within the provinces and autonomous regions (PARs) in China, the levels of coordinated development of inter-subsystems are high, while the coordinated development between the elements within a single subsystem level are low. Furthermore, a positive coherent effect is exerted on the comprehensive coordination degree of CSR3ES by the inter-system synergistic effects. (3) In terms of spatial correlation, five comprehensive coordinated development modes of CSR3ES are formed: the northeast regional coordination mode group; the northwest regional uncoordinated mode group; the southeast regional coordination mode group; the central regional random mode group; and the Beijing-Tianjin-Hebei polarization mode. Full article

(This article belongs to the Section Sustainable Engineering and Science)

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887 KiB

Open AccessArticle

Soil Seed Bank and Plant Community Development in Passive Restoration of Degraded Sandy Grasslands

by Renhui Miao, Yongheng Song, Zhaolin Sun, Meixia Guo, Zhenxing Zhou and Yinzhan Liu

Sustainability 2016, 8(6), 581; https://doi.org/10.3390/su8060581 - 21 Jun 2016

Cited by 27 | Viewed by 6708

Abstract

To evaluate the efficacy of passive restoration on soil seed bank and vegetation recovery, we measured the species composition and density of the soil seed bank, as well as the species composition, density, coverage, and height of the extant vegetation in sites passively [...] Read more.

To evaluate the efficacy of passive restoration on soil seed bank and vegetation recovery, we measured the species composition and density of the soil seed bank, as well as the species composition, density, coverage, and height of the extant vegetation in sites passively restored for 0, 4, 7, and 12 years (S0, S4, S7, and S12) in a degraded grassland in desert land. Compared with S0, three more species in the soil seed bank at depths of 0–30 cm and one more plant species in the community was detected in S12. Seed density within the topsoil (0–5 cm) was five times higher in S12 than that in S0. Plant densities in S7 and S12 were triple and quadruple than that in S0. Plant coverage was increased by 1.5 times (S4), double (S7), and triple (S12) compared with S0. Sørensen’s index of similarity in species composition between the soil seed bank and the plant community were high (0.43–0.63), but it was lower in short-term restoration sites (S4 and S7) than that in no and long-term restoration sites (S0 and S12). The soil seed bank recovered more slowly than the plant community under passive restoration. Passive restoration is a useful method to recover the soil seed bank and vegetation in degraded grasslands. Full article

(This article belongs to the Special Issue Earth Observation and Geoinformation Technologies for Sustainable Development)

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551 KiB

Open AccessArticle

Supporting Farmer-Led Irrigation in Mozambique: Reflections on Field-Testing a New Design Approach

by Wouter Beekman and Gert Jan Veldwisch

Sustainability 2016, 8(6), 580; https://doi.org/10.3390/su8060580 - 20 Jun 2016

Cited by 5 | Viewed by 5515

Abstract

Smallholder irrigation technologies introduced in sub-Saharan Africa are often unsustainable in the sense that they are not maintained by their users. In contrast, there is clear evidence that smallholder farmers have been developing and expanding irrigated areas. An approach was developed that takes [...] Read more.

Smallholder irrigation technologies introduced in sub-Saharan Africa are often unsustainable in the sense that they are not maintained by their users. In contrast, there is clear evidence that smallholder farmers have been developing and expanding irrigated areas. An approach was developed that takes these farmers’ initiatives as a starting point to stimulate further irrigated agricultural expansion in central Mozambique, dubbed the PIAD approach (Participatory Irrigated Agricultural Development). The approach was documented through field diaries, participatory monitoring and evaluation. This article presents an analysis and reflection on the design process. Amongst other things, it shows that a crucial difference is the division of roles between users, contractors and irrigation engineers, both in terms of division of responsibilities and in understanding the interdisciplinary connections of irrigated agricultural production. The approach allowed users to be kept in the driver’s seat of development while going beyond improving irrigation infrastructure, including agronomic and institutional interventions. Additionally, the results show that technologies are being sustained by their users and copied by farmers in neighboring areas. We conclude that the approach allows for active investment by the users, both in design as well as in project costs and labor, which later results in the improvements being maintained and copied, a clear marker of sustainability. Full article

(This article belongs to the Special Issue Sustainable Irrigation and Drainage)

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1794 KiB

Open AccessArticle

A Study on Life Cycle CO₂ Emissions of Low-Carbon Building in South Korea

by Su-Hyun Cho and Chang-U Chae

Sustainability 2016, 8(6), 579; https://doi.org/10.3390/su8060579 - 20 Jun 2016

Cited by 81 | Viewed by 13907

Abstract

There have been much interest and many efforts to control global warming and reduce greenhouse gas (GHG) emissions throughout the world. Recently, the Republic of Korea has also increased its GHG reduction goal and searched for an implementation plan. In buildings, for example, [...] Read more.

There have been much interest and many efforts to control global warming and reduce greenhouse gas (GHG) emissions throughout the world. Recently, the Republic of Korea has also increased its GHG reduction goal and searched for an implementation plan. In buildings, for example, there have been technology developments and deployment policies to reduce GHG emissions from a life cycle perspective, covering construction materials, building construction, use of buildings and waste disposal. In particular, Korea’s Green Standard for Energy and Environmental Design is a certification of environmentally-friendly buildings for their energy saving and reduction of environmental pollution throughout their lives. In fact, the demand and adoption of the certification are rising every year. In construction materials and buildings, as a result, an environmentally-friendly aspect has become crucial. The importance of construction material and building development technologies that can reduce environmental load by diminishing GHG emissions in buildings has emerged. Moreover, there has been a rising necessity to verify the GHG reduction effects of buildings. To assess the reduction of carbon emissions in the buildings built with low-carbon construction technologies and materials, therefore, this study estimated life cycle carbon emissions in reference buildings in which general construction materials are used and in low-carbon buildings. For this, the carbon emissions and their reduction from construction materials (especially concrete) between conventional products and low-carbon materials were estimated, using Life Cycle Assessment (LCA). After estimating carbon emissions from a building life cycle perspective, their reduction in low-carbon buildings compared to the reference buildings was reviewed. The results found that compared to conventional buildings, low-carbon buildings revealed a 25% decrease in carbon emissions in terms of the reduction of Life Cycle CO₂ (LCCO₂) per unit area. If diverse production technologies and sales routes are further developed for low-carbon construction materials, carbon emission reduction effects would considerably increase. Full article

(This article belongs to the Section Sustainable Urban and Rural Development)

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5089 KiB

Open AccessArticle

Evaluation of Thermal Anomalies in Multi-Boreholes Field Considering the Effects of Groundwater Flow

by Shibin Geng, Yong Li, Xu Han, Huiliang Lian and Hua Zhang

Sustainability 2016, 8(6), 577; https://doi.org/10.3390/su8060577 - 20 Jun 2016

Cited by 12 | Viewed by 4677

Abstract

In this paper, the performance of multiple boreholes (multi-BHEs) field is evaluated by considering the groundwater flow. Optimization strategies are presented to mitigate thermal anomalies in the BHEs field. This study shows that groundwater flow greatly improves the heat transfer but causes thermal [...] Read more.

In this paper, the performance of multiple boreholes (multi-BHEs) field is evaluated by considering the groundwater flow. Optimization strategies are presented to mitigate thermal anomalies in the BHEs field. This study shows that groundwater flow greatly improves the heat transfer but causes thermal anomalies downstream. To overcome this problem, a heat transfer model is established for multi-boreholes based on temperature field superposition and moving finite line source model (MFLS). The MFLS multi-boreholes model considers the axial effect and groundwater flow and produces results in agreement with the field tested data of a 4 × 4 boreholes field. Using a dynamic annual load pattern, the long-term performance of the 4 × 4 boreholes field is analyzed. Three dynamic diurnal cooling load models are proposed to evaluate the temperature changes in the underground. The intermittent load model could reduce the local temperature anomalies in downstream tubes. The optimization model for cooling cases for multi-BHEs is elaborated to keep the outlet temperature as low as possible and minimize the extreme temperature anomalies, and by this, ultimately improve the system performance. Furthermore, the temperature variations and thermal anomalies downstream of multi-BHEs are investigated by evaluating the arrangement optimization and load optimization. The results show that the optimization could mitigate thermal anomalies downstream and reduce the rate of temperature imbalance of the BHEs field. Full article

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Open AccessArticle

Modeling the Habitat of the Red-Crowned Crane (Grus japonensis) Wintering in Cheorwon-Gun to Support Decision Making

by Ho Gul Kim, Eun-jae Lee, Chan Park, Ki Sup Lee, Dong Kun Lee, Woo-shin Lee and Jong-U Kim

Sustainability 2016, 8(6), 576; https://doi.org/10.3390/su8060576 - 18 Jun 2016

Cited by 10 | Viewed by 15051

Abstract

Cheorwon-gun is an important wintering area for the red-crowned crane (Grus japonensis). Although eco-tourism has been recently proposed as a means to stimulate the local economy, it may have adverse effects on the crane. We believe a science-based conservation plan is [...] Read more.

Cheorwon-gun is an important wintering area for the red-crowned crane (Grus japonensis). Although eco-tourism has been recently proposed as a means to stimulate the local economy, it may have adverse effects on the crane. We believe a science-based conservation plan is needed to mitigate these negative effects. To this end, our study had three objectives: (1) to analyze the red-crowned crane habitat and its suitability in Cheorwon-gun, using field surveys and habitat modeling; (2) to check the feasibility of alternative habitat patches across demilitarized zones (DMZs); and (3) to propose a conceptual diagram that minimizes habitat loss during development activities. We aim to quantify habitat suitability, the farmland area needed to support existing crane populations in wintertime, disturbance caused by human activities, and vehicular spatial patterns. These data could be used in spatial planning. The framework of this study and the process of making a conceptual diagram could be applied to other areas where there is a conflict between development and habitat conservation. Full article

(This article belongs to the Special Issue Sustainable Wildlife Management)

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Open AccessArticle

From Food Waste to Donations: The Case of Marketplaces in Northern Spain

by Pilar L. González-Torre and Jorge Coque

Sustainability 2016, 8(6), 575; https://doi.org/10.3390/su8060575 - 18 Jun 2016

Cited by 18 | Viewed by 7243

Abstract

There is a growing increase in the number of disadvantaged people whose basic needs, such as food, should be covered. In crisis periods, food banks and other entities have a special role to play in that social function. This research focuses on the [...] Read more.

There is a growing increase in the number of disadvantaged people whose basic needs, such as food, should be covered. In crisis periods, food banks and other entities have a special role to play in that social function. This research focuses on the marketplaces that are great generators of organic food waste due to the fact that almost all of their stalls are dedicated to the sales of fresh food. The work combines both qualitative (interviews with the person responsible for most of the marketplaces in a northern Spain region and with two health inspectors, as well as a participatory workshop with different stakeholders related to food recovery: a regional waste management company, a food bank and several beneficiary entities) and quantitative techniques (a massive survey of the market stalls where the interviews were previously conducted). The results allow us to estimate the volume of organic waste generated by these marketplaces and to propose guidelines that would facilitate a better management of the food surpluses with potential for use, in the first place, as donations to food banks and, secondly, as recoverable bio-waste. Full article

(This article belongs to the Section Economic and Business Aspects of Sustainability)

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233 KiB

Open AccessFeature PaperReview

Agroforestry—The Next Step in Sustainable and Resilient Agriculture

by Matthew Heron Wilson and Sarah Taylor Lovell

Sustainability 2016, 8(6), 574; https://doi.org/10.3390/su8060574 - 18 Jun 2016

Cited by 129 | Viewed by 35073

Abstract

Agriculture faces the unprecedented task of feeding a world population of 9 billion people by 2050 while simultaneously avoiding harmful environmental and social effects. One effort to meet this challenge has been organic farming, with outcomes that are generally positive. However, a number [...] Read more.

Agriculture faces the unprecedented task of feeding a world population of 9 billion people by 2050 while simultaneously avoiding harmful environmental and social effects. One effort to meet this challenge has been organic farming, with outcomes that are generally positive. However, a number of challenges remain. Organic yields lag behind those in conventional agriculture, and greenhouse gas emissions and nutrient leaching remain somewhat problematic. In this paper, we examine current organic and conventional agriculture systems and suggest that agroforestry, which is the intentional combination of trees and shrubs with crops or livestock, could be the next step in sustainable agriculture. By implementing systems that mimic nature’s functions, agroforestry has the potential to remain productive while supporting a range of ecosystem services. In this paper, we outline the common practices and products of agroforestry as well as beneficial environmental and social effects. We address barriers to agroforestry and explore potential options to alter policies and increase adoption by farmers. We conclude that agroforestry is one of the best land use strategies to contribute to food security while simultaneously limiting environmental degradation. Full article

(This article belongs to the Special Issue Sustainable Agriculture–Beyond Organic Farming)

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Open AccessArticle

Beef Cattle Farms’ Conversion to the Organic System. Recommendations for Success in the Face of Future Changes in a Global Context

by Alfredo J. Escribano

Sustainability 2016, 8(6), 572; https://doi.org/10.3390/su8060572 - 18 Jun 2016

Cited by 16 | Viewed by 11207

Abstract

Dehesa is a remarkable agroforestry system, which needs the implementation of sustainable production systems in order to reduce its deterioration. Moreover, its livestock farms need to adapt to a new global market context. As a response, the organic livestock sector has expanded not [...] Read more.

Dehesa is a remarkable agroforestry system, which needs the implementation of sustainable production systems in order to reduce its deterioration. Moreover, its livestock farms need to adapt to a new global market context. As a response, the organic livestock sector has expanded not only globally but also in the region in search for increased overall sustainability. However, conversions to the organic system have been commonly carried out without analyzing farms’ feasibility to do so. This analysis is necessary before implementing any new production system in order to reduce both the diversity of externalities that the variety of contexts leads to and the vulnerability of the DDehesa ecosystem to small management changes. Within this context and in the face of this gap in knowledge, the present paper analyzes the ease of such conversions and the farms’ chances of success after conversion in the face of global changes (market and politics). Different aspects (“areas of action”) were studied and integrated within the Global Conversion Index (GCI), and the legal requirement for European organic farming, organic principles, future challenges for ruminants’ production systems, as well as the lines of action for the post-2013 CAP (Common Agricultural Policy) and their impacts on the beef cattle sector were taken into account. Results revealed that farms must introduce significant changes before initiating the conversion process, since they had very low scores on the GCI (42.74%), especially with regard to health and agro-ecosystem management (principle of Ecology). Regarding rearing and animal welfare (principle of justice/fairness), farms were close to the organic system. From the social point of view, active participation in manufacturing and marketing of products should be increased. Full article

(This article belongs to the Special Issue Sustainable Agriculture–Beyond Organic Farming)

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1861 KiB

Open AccessArticle

Residents’ Environmental Conservation Behaviors at Tourist Sites: Broadening the Norm Activation Framework by Adopting Environment Attachment

by Yuling Zhang, Jie Zhang, Yuyao Ye, Qitao Wu, Lixia Jin and Hongou Zhang

Sustainability 2016, 8(6), 571; https://doi.org/10.3390/su8060571 - 18 Jun 2016

Cited by 20 | Viewed by 6777

Abstract

Understanding the factors that affect residents’ environmental conservation behaviors help in managing the environment of tourist sites. This research provides an integrative understanding of how residents near tourist sites form their environmental conservation behaviors by merging the norm-activation model and cognitive-affective model into [...] Read more.

Understanding the factors that affect residents’ environmental conservation behaviors help in managing the environment of tourist sites. This research provides an integrative understanding of how residents near tourist sites form their environmental conservation behaviors by merging the norm-activation model and cognitive-affective model into one theoretical framework. Results of the structural analysis from a sample of 642 residents showed that this study’s proposed composite model includes a satisfactory level of predictive power for environmental conservation behaviors. The findings identify the following two dimensions of awareness of environmental consequences as having a key role in predicting environmental conservation behaviors: (1) awareness of positive consequences of environmental protection; and (2) awareness of disaster consequences. Results also show that environment attachment and personal norms about environmentalism played a mediating role between awareness of environmental consequences and environmental conservation behaviors, and that personal norms about environmentalism were the most powerful factor in predicting behaviors. Several practical implications were derived from the research findings that can contribute to environment management policy both within and outside the field of tourism, mostly notably: (1) how the effective promotion of these factors can encourage environmental conservation behaviors for residents; and (2) how governments can develop and implement environmental management measures to improve locals’ awareness of positive consequences of environmental protection. Full article

(This article belongs to the Section Environmental Sustainability and Applications)

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Open AccessFeature PaperReview

Soil Conservation Issues in India

by Ranjan Bhattacharyya, Birendra Nath Ghosh, Pradeep Dogra, Prasanta Kumar Mishra, Priyabrata Santra, Suresh Kumar, Michael Augustine Fullen, Uttam Kumar Mandal, Kokkuvayil Sankaranarayanan Anil, Manickam Lalitha, Dibyendu Sarkar, Dibyendu Mukhopadhyay, Krishnendu Das, Madan Pal, Rajbir Yadav, Ved Prakash Chaudhary and Brajendra Parmar

Sustainability 2016, 8(6), 565; https://doi.org/10.3390/su8060565 - 18 Jun 2016

Cited by 38 | Viewed by 26866

Abstract

Despite years of study and substantial investment in remediation and prevention, soil erosion continues to be a major environmental problem with regard to land use in India and elsewhere around the world. Furthermore, changing climate and/or weather patterns are exacerbating the problem. Our [...] Read more.

Despite years of study and substantial investment in remediation and prevention, soil erosion continues to be a major environmental problem with regard to land use in India and elsewhere around the world. Furthermore, changing climate and/or weather patterns are exacerbating the problem. Our objective was to review past and current soil conservation programmes in India to better understand how production-, environmental-, social-, economic- and policy-related issues have affected soil and water conservation and the incentives needed to address the most critical problems. We found that to achieve success in soil and water conservation policies, institutions and operations must be co-ordinated using a holistic approach. Watershed programmes have been shown to be one of the most effective strategies for bringing socio-economic change to different parts of India. Within both dryland and rainfed areas, watershed management has quietly revolutionized agriculture by aligning various sectors through technological soil and water conservation interventions and land-use diversification. Significant results associated with various watershed-scale soil and water conservation programmes and interventions that were effective for reducing land degradation and improving productivity in different parts of the country are discussed. Full article

(This article belongs to the Special Issue Soil Science in Conservation Agricultural Systems)

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1319 KiB

Open AccessArticle

Analysis of Factors in Land Subsidence in Shanghai: A View Based on a Strategic Environmental Assessment

by Ye-Shuang Xu, Shui-Long Shen, Dong-Jie Ren and Huai-Na Wu

Sustainability 2016, 8(6), 573; https://doi.org/10.3390/su8060573 - 17 Jun 2016

Cited by 132 | Viewed by 8259

Abstract

It has been observed that in the urban center of Shanghai, land subsidence has accelerated, and the groundwater level has continued to drop even though the net withdrawn volume (NWV) of groundwater has remained unchanged since 1980. An analysis of monitoring data shows [...] Read more.

It has been observed that in the urban center of Shanghai, land subsidence has accelerated, and the groundwater level has continued to drop even though the net withdrawn volume (NWV) of groundwater has remained unchanged since 1980. An analysis of monitoring data shows that drawdown of the groundwater level is one of the factors that have influenced land subsidence since 1980. The NWV of groundwater in urban areas, however, is not the critical factor controlling the drawdown of the groundwater level. Since the 1980s, there have been many underground works constructed in the unique strata of Shanghai, which has an interlayered structure known as a multi-aquifer-aquitard system (MAAS). Investigation into land subsidence caused by urban construction is now receiving much attention. Based on the principle of a strategic environmental assessment (SEA) for sustainable urban development, this paper presents a discussion and analysis of the factors which can influence the development of land subsidence during continued urbanization in Shanghai. The main factors include the additional loading caused by the construction of structures, the cut-off effect due to construction in aquifers, the drawdown of groundwater level caused by leakage into underground structures, and the decrease of groundwater recharge from neighboring zones. SEA is recommended for the future development of Shanghai. Full article

(This article belongs to the Section Sustainable Engineering and Science)

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2250 KiB

Open AccessArticle

Cultural Attitudes as WTP Determinants: A Revised Cultural Worldview Scale

by Andy S. Choi and Kelly S. Fielding

Sustainability 2016, 8(6), 570; https://doi.org/10.3390/su8060570 - 17 Jun 2016

Cited by 14 | Viewed by 6384

Abstract

There has been little attention paid to the systematic measurement issue of general attitudes toward human-culture relationships. This paper applied the Cultural Worldview (CW) scale that was developed by Choi et al. in 2007 (published in the Journal of Cultural Economics), and [...] Read more.

There has been little attention paid to the systematic measurement issue of general attitudes toward human-culture relationships. This paper applied the Cultural Worldview (CW) scale that was developed by Choi et al. in 2007 (published in the Journal of Cultural Economics), and investigated its dimensionality and relationship with willingness to pay (WTP) for cultural heritage protection through a sequential integration between latent variables and valuation models. A case study of 997 Korean respondents was employed to examine conservation values of cultural heritage sites using discrete choice models. Confirmatory factor analyses demonstrated that this scale can be used either as a single second-order factor or four correlated factors. A more parsimonious version of the CW scale with twelve items is endorsed in this paper and the results also confirm that it is valid for use with non-Western nations. The findings support a significant attitude–WTP relationship; there was a significant role of the CW scale that reveals unobserved factors in valuation models. Full article

(This article belongs to the Special Issue Sustainability of Cultural and Natural Heritage)

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761 KiB

Open AccessArticle

Vertical Coordination in Organic Food Chains: A Survey Based Analysis in France, Italy and Spain

by Alessia Cavaliere, Massimo Peri and Alessandro Banterle

Sustainability 2016, 8(6), 569; https://doi.org/10.3390/su8060569 - 17 Jun 2016

Cited by 14 | Viewed by 5402

Abstract

The paper analyses characteristics of vertical relationships of organic supply chains with a specific focus on the processing and retailing sectors. The analysis takes into account different regions of the EU Mediterranean area. Data were collected through interviews using an ad hoc questionnaire. [...] Read more.

The paper analyses characteristics of vertical relationships of organic supply chains with a specific focus on the processing and retailing sectors. The analysis takes into account different regions of the EU Mediterranean area. Data were collected through interviews using an ad hoc questionnaire. The survey was based on a sample of 306 firms, including processors and retailers. The analysis revealed that a relevant aspect for the processing firms of organic products concerns the guaranteeing of safety and quality levels for the products. The main tools to implement the quality management are based on the adoption of specific production regulations and quality controls. The premium price most frequently applied by processors ranges from 10% to 40% and similar values are revealed for retailers. The diffusion of supply contracts allows the vertical coordination between agriculture and processing firms in the organic supply chains. The main distribution channels for the processing firms are represented by specialised shops in organic products, direct sales and supermarkets. Full article

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718 KiB

Open AccessArticle

Assimilation and Translocation of Dry Matter and Phosphorus in Rice Genotypes Affected by Salt-Alkaline Stress

by Zhijie Tian, Jingpeng Li, Xueying Jia, Fu Yang and Zhichun Wang

Sustainability 2016, 8(6), 568; https://doi.org/10.3390/su8060568 - 17 Jun 2016

Cited by 20 | Viewed by 5374

Abstract

Salt-alkaline stress generally leads to soil compaction and fertility decline. It also restricts rice growth and phosphorus acquisition. In this pot experiment, two relatively salt-alkaline tolerant (Dongdao-4 and Changbai-9) and sensitive (Changbai-25 and Tongyu-315) rice genotypes were planted in sandy (control) and salt-alkaline [...] Read more.

Salt-alkaline stress generally leads to soil compaction and fertility decline. It also restricts rice growth and phosphorus acquisition. In this pot experiment, two relatively salt-alkaline tolerant (Dongdao-4 and Changbai-9) and sensitive (Changbai-25 and Tongyu-315) rice genotypes were planted in sandy (control) and salt-alkaline soil to evaluate the characteristics of dry matter and phosphorus assimilation and translocation in rice. The results showed that dry matter and phosphorus assimilation in rice greatly decreased under salt-alkaline stress as the plants grew. The translocation and contribution of dry matter and phosphorus to the grains also increased markedly; different performances were observed between genotypes under salt-alkaline stress. D4 and C9 showed higher dry matter translocation, translocation efficiency and contribution of dry matter assimilation to panicles than those of C25 and T315. These changes in D4 and C9 indexes occurred at low levels of salt-alkaline treatment. Higher phosphorus acquisition efficiency of D4 and C9 were also found under salt-alkaline conditions. Additionally, the phosphorus translocation significantly decreased in C25 and T315 in the stress treatment. In conclusion, the results indicated that salt-alkaline-tolerant rice genotypes may have stronger abilities to assimilate and transfer biomass and phosphorus than sensitive genotypes, especially in salt-alkaline conditions. Full article

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4349 KiB

Open AccessArticle

Building Simplified Life Cycle CO₂ Emissions Assessment Tool (B‐SCAT) to Support Low‐Carbon Building Design in South Korea

by Seungjun Roh and Sungho Tae

Sustainability 2016, 8(6), 567; https://doi.org/10.3390/su8060567 - 17 Jun 2016

Cited by 23 | Viewed by 7872

Abstract

Various tools that assess life cycle CO₂ (LCCO₂) emissions are currently being developed throughout the international community. However, most building LCCO₂ emissions assessment tools use a bill of quantities (BOQ), which is calculated after starting a building’s construction. Thus, [...] Read more.

Various tools that assess life cycle CO₂ (LCCO₂) emissions are currently being developed throughout the international community. However, most building LCCO₂ emissions assessment tools use a bill of quantities (BOQ), which is calculated after starting a building’s construction. Thus, it is difficult to assess building LCCO₂ emissions during the early design phase, even though this capability would be highly effective in reducing LCCO₂ emissions. Therefore, the purpose of this study is to develop a Building Simplified LCCO₂ emissions Assessment Tool (B‐SCAT) for application in the early design phase of low‐carbon buildings in South Korea, in order to facilitate efficient decision‐making. To that end, in the construction stage, the BOQ and building drawings were analyzed, and a database of quantities and equations describing the finished area were conducted for each building element. In the operation stage, the “Korea Energy Census Report” and the “Korea Building Energy Efficiency Rating Certification System” were analyzed, and three kinds of models to evaluate CO₂ emissions were proposed. These analyses enabled the development of the B‐SCAT. A case study compared the assessment results performed using the B‐SCAT against a conventional assessment model based on the actual BOQ of the evaluated building. These values closely approximated the conventional assessment results with error rates of less than 3%. Full article

(This article belongs to the Special Issue Life Cycle Assessment on Green Building Implementation)

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1402 KiB

Open AccessArticle

The Livelihood Vulnerability of Rural Households in Earthquake-Stricken Areas—A Case Study of Ning’er, Yunnan Province

by Benyong Wei, Guiwu Su, Wenhua Qi and Lei Sun

Sustainability 2016, 8(6), 566; https://doi.org/10.3390/su8060566 - 17 Jun 2016

Cited by 17 | Viewed by 5549

Abstract

Earthquakes happen suddenly and are immensely destructive. They not only destroy entire societal production and infrastructure systems but also seriously interfere with daily life and reduce opportunities to earn income in earthquake-affected areas. In this paper, using the Ning’er Ms 6.4 earthquake in [...] Read more.

Earthquakes happen suddenly and are immensely destructive. They not only destroy entire societal production and infrastructure systems but also seriously interfere with daily life and reduce opportunities to earn income in earthquake-affected areas. In this paper, using the Ning’er Ms 6.4 earthquake in 2007 as an example, we analyzed the livelihood vulnerability of rural households in Ning’er County, Yunnan, based on data from questionnaires and on-site interviews. The results showed that on the whole, local rural household livelihoods are relatively vulnerable in the earthquake-affected area of Ning’er. The main reason for the high level of vulnerability of rural households is the lack of single or multiple incomes. Due to the shortage of household income, the capacity of rural households to manage the aftermath of an earthquake is low. Improving the income allocation and transformation level and expanding methods of earning income is an effective way for rural households to decrease livelihood vulnerability in earthquake-prone areas. Some suggestions are given for local rural households to enhance their livelihood income levels in the event of earthquakes. Full article

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625 KiB

Open AccessArticle

Sustainable Supply Chain Management: The Influence of Disposal Scenarios on the Environmental Impact of a 2400 L Waste Container

by José Eduardo Galve, Daniel Elduque, Carmelo Pina and Carlos Javierre

Sustainability 2016, 8(6), 564; https://doi.org/10.3390/su8060564 - 17 Jun 2016

Cited by 13 | Viewed by 6888

Abstract

This paper analyzes the influence of the supply chain management on the environmental impact of a 2400 L waste disposal container used in most cities of Spain. The studied functional unit, a waste disposal container, made up mostly of plastic materials and a [...] Read more.

This paper analyzes the influence of the supply chain management on the environmental impact of a 2400 L waste disposal container used in most cities of Spain. The studied functional unit, a waste disposal container, made up mostly of plastic materials and a metallic structure, and manufactured in Madrid (Spain), is distributed to several cities at an average distance of 392 km. A life cycle assessment of four different scenarios (SC) has been calculated with the software EcoTool v4.0 (version 4.0; i+: Zaragoza, Spain, 2015) and using Ecoinvent v3.0 database (version 3.0; Swiss Centre for Life Cycle Inventories: St. Gallen, Switzerland, 2013). The environmental impact has been characterized with two different methodologies, recipe and carbon footprint. In order to reduce the environmental impact, several end of life scenarios have been performed, analyzing the influence of the supply chain on a closed-looped system that increases recycling. Closed loop management of the waste and reuse of parts allows companies to stop selling products and start selling the service that their products give to the consumers. Full article

(This article belongs to the Special Issue Sustainability in Supply Chain Management)

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4446 KiB

Open AccessArticle

Biomass Power Generation Investment in China: A Real Options Evaluation

by Mingming Zhang, Dequn Zhou, Hao Ding and Jingliang Jin

Sustainability 2016, 8(6), 563; https://doi.org/10.3390/su8060563 - 17 Jun 2016

Cited by 15 | Viewed by 6512

Abstract

This paper proposes a real options model for evaluating the biomass power generation investment in China. The uncertainties in the market price of electricity, CO₂ price and straw price are considered. Meanwhile the dynamic relationship between installed capacity and fuel cost, as [...] Read more.

This paper proposes a real options model for evaluating the biomass power generation investment in China. The uncertainties in the market price of electricity, CO₂ price and straw price are considered. Meanwhile the dynamic relationship between installed capacity and fuel cost, as well as the long-term reduction of subsidy are described. Two scenarios, i.e., with the carbon emission trading scheme existent and non-existent, respectively, is built to empirically analyze the investment of a 25-MW straw-based power generation project. The results show that investors should undertake the investment in 2030 under two scenarios. Investment values are 14,869,254.8 and 37,608,727 Chinese Yuan (RMB), respectively. The implementation of the carbon emission trading scheme theoretically helps improve investment value and advance the most likely optimal investment time. However, the current CO₂ price is not sufficient to advance the most likely optimal investment time. The impacts of several factors, including subsidy policy, CO₂ price, straw price, installed capacity, correlation structure and the validity period of investment, on the optimal investment strategy are also examined. It is suggested that governments take some measures, including increasing subsidy, setting the growth pattern of subsidy and establishing and perfecting a nationwide carbon trading market, to improve the investment environment and attract more investments. Full article

(This article belongs to the Special Issue Sustainable Biofuel Production)

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3802 KiB

Open AccessArticle

Optimal Hybrid Renewable Airport Power System: Empirical Study on Incheon International Airport, South Korea

by Seoin Baek, Heetae Kim and Hyun Joon Chang

Sustainability 2016, 8(6), 562; https://doi.org/10.3390/su8060562 - 17 Jun 2016

Cited by 16 | Viewed by 7256

Abstract

In response to global energy problems (e.g., the oil crisis, the Fukushima accident, the Paris Agreement), the South Korean government has executed a strict renewable energy plan to decrease the country’s dependence on fossil fuel. Public facilities, such as international airports, which use [...] Read more.

In response to global energy problems (e.g., the oil crisis, the Fukushima accident, the Paris Agreement), the South Korean government has executed a strict renewable energy plan to decrease the country’s dependence on fossil fuel. Public facilities, such as international airports, which use substantial amounts of electricity, are the most in need of government regulation. In this study, we attempt to determine the optimal hybrid electricity generation system for South Korea’s largest airport: Incheon International Airport. In the analysis, we use three scenarios: the current load, 120% of the current load, and 140% of the current load, according to the plan to expand Incheon International Airport. According to the COE (cost of electricity) and the NPC (net present cost) of the result, it is economically feasible to completely cover the potential increase in the electric load with PV power. Government policy implications and limitations are discussed. Full article

(This article belongs to the Section Economic and Business Aspects of Sustainability)

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2270 KiB

Open AccessArticle

Heterotrophic Anodic Denitrification in Microbial Fuel Cells

by Jakub Drewnowski and Francisco Jesus Fernandez-Morales

Sustainability 2016, 8(6), 561; https://doi.org/10.3390/su8060561 - 17 Jun 2016

Cited by 16 | Viewed by 5337

Abstract

Nowadays, pollution caused by energy production systems is a major environmental concern. Therefore, the development of sustainable energy sources is required. Amongst others, the microbial fuel cell (MFC) seems to be a possible solution because it can produce clean energy at the same [...] Read more.

Nowadays, pollution caused by energy production systems is a major environmental concern. Therefore, the development of sustainable energy sources is required. Amongst others, the microbial fuel cell (MFC) seems to be a possible solution because it can produce clean energy at the same time that waste is stabilized. Unfortunately, mainly due to industrial discharges, the wastes could contain nitrates, or nitrates precursors such ammonia, which could lead to lower performance in terms of electricity production. In this work, the feasibility of coupling anodic denitrification process with electricity production in MFC and the effect of the nitrates over the MFC performance were studied. During the experiments, it was observed that the culture developed in the anodic chamber of the MFC presented a significant amount of denitrificative microorganisms. The MFC developed was able to denitrify up to 4 ppm, without affecting the current density exerted, of about 1 mA/cm². Regarding the denitrification process, it must be highlighted that the maximum denitrification rate achieved with the culture was about 60 mg·NO₃⁻·L⁻¹·h⁻¹. Based on these results, it can be stated that it is possible to remove nitrates and to produce energy, without negatively affecting the electrical performance, when the nitrate concentration is low. Full article

(This article belongs to the Special Issue Sustainable Biofuel Production)

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3373 KiB

Open AccessArticle

Effect of Thermal Bridges in Insulated Walls on Air-Conditioning Loads Using Whole Building Energy Analysis

by Mohamed F. Zedan, Sami Al-Sanea, Abdulaziz Al-Mujahid and Zeyad Al-Suhaibani

Sustainability 2016, 8(6), 560; https://doi.org/10.3390/su8060560 - 16 Jun 2016

Cited by 16 | Viewed by 6938

Abstract

Thermal bridges in building walls are usually caused by mortar joints between insulated building blocks and by the presence of concrete columns and beams within the building envelope. These bridges create an easy path for heat transmission and therefore increase air-conditioning loads. In [...] Read more.

Thermal bridges in building walls are usually caused by mortar joints between insulated building blocks and by the presence of concrete columns and beams within the building envelope. These bridges create an easy path for heat transmission and therefore increase air-conditioning loads. In this study, the effects of mortar joints only on cooling and heating loads in a typical two-story villa in Riyadh are investigated using whole building energy analysis. All loads found in the villa, which broadly include ventilation, transmission, solar and internal loads, are considered with schedules based on local lifestyles. The thermal bridging effect of mortar joints is simulated by reducing wall thermal resistance by a percentage that depends on the bridges to wall area ratio (TB area ratio or A_mj/A_tot) and the nominal thermal insulation thickness (L_ins). These percentage reductions are obtained from a correlation developed by using a rigorous 2D dynamic model of heat transmission through walls with mortar joints. The reduction in thermal resistance is achieved through minor reductions in insulation thickness, thereby keeping the thermal mass of the wall essentially unchanged. Results indicate that yearly and monthly cooling loads increase almost linearly with the thermal bridge to wall area ratio. The increase in the villa’s yearly loads varies from about 3% for A_mj/A_tot = 0.02 to about 11% for A_mj/A_tot = 0.08. The monthly increase is not uniform over the year and reaches a maximum in August, where it ranges from 5% for A_mj/A_tot = 0.02 to 15% for A_mj/A_tot = 0.08. In winter, results show that yearly heating loads are generally very small compared to cooling loads and that heating is only needed in December, January and February, starting from late night to late morning. Monthly heating loads increase with the thermal bridge area ratio; however, the variation is not as linear as observed in cooling loads. The present results highlight the importance of reducing or eliminating thermal bridging effects resulting from mortar joints in walls by maintaining the continuity of the insulation layer in order to reduce energy consumption in air-conditioned buildings. Full article

(This article belongs to the Section Energy Sustainability)

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