Emergy Assessment of a Wheat-Maize Rotation System with Different Water Assignments in the North China Plain

Sustainable water use is seriously compromised in the North China Plain (NCP) due to the huge water requirements of agriculture, the largest use of water resources. An integrated approach which combines the ecosystem model with emergy analysis is presented to determine the optimum quantity of irrigation for sustainable development in irrigated cropping systems. Since the traditional emergy method pays little attention to the dynamic interaction among components of the ecological system and dynamic emergy accounting is in its infancy, it is hard to evaluate the cropping system in hypothetical situations or in response to specific changes. In order to solve this problem, an ecosystem model (Vegetation Interface Processes (VIP) model) is introduced for emergy analysis to describe the production processes. Some raw data, collected by investigating or observing in conventional emergy analysis, may be calculated by the VIP model in the new approach. To demonstrate the advantage of this new approach, we use it to assess the wheat-maize rotation cropping system at different irrigation levels and derive the optimum quantity of irrigation according to the index of ecosystem sustainable development in NCP. The results show, the optimum quantity of irrigation in this region should be 240–330 mm per year in the wheat system and no irrigation in the maize system, because with this quantity of irrigation the rotation crop system reveals: best efficiency in energy transformation (transformity = 6.05E + 4 sej/J); highest sustainability (renewability = 25%); lowest environmental impact (environmental loading ratio = 3.5) and the greatest sustainability index (Emergy Sustainability Index = 0.47) compared with the system in other irrigation amounts. This study demonstrates that application of the new approach is broader than the conventional emergy analysis and the new approach is helpful in optimizing resources allocation, resource-savings and maintaining agricultural sustainability.     

Emergy evaluation and economic analysis of three wetland fish farming systems in Nansi Lake area,China

Emergy and economic methods were used to evaluate and compare three fish production models, i.e., cage fish farming system, pond intensive fish rearing system and semi-natural extensive pond fish rearing system, in Nansi Lake area in China in the year 2007. The goal of this study was to understand the benefits and driving forces of selected fish production models from ecological and economic points of view. The study considered input structure, production efficiency, environmental impacts, economic viability and sustainability. Results show that the main difference among the three production systems was the emergy cost for fish feed associated with their feeding system, i.e., feeding on natural biomass such as plankton and grass or on commercial feedstock. As indicated by EYR, ELR and ESI, it can be clearly shown that the intensive production model with commercial feed is not a sustainable pattern. However, the point is that more environmentally sound patterns do not seem able to provide a competitive net profit in the short run. The intensive pond fish farming system had a net profit of 2.57E+03 $/ha, much higher than 1.27E+03 $/ha for cage fish farming system and slightly higher than 2.37E+03 $/ha for semi-natural fish farming system. With regard to the drivers of local farmer’s decisions, the accessibility of land for the required use and investment ability determine the farmer’s choice of the production model and the scale of operation, while other factors seem to have little effect. Theoretically, the development of environmentally sustainable production patterns, namely water and land conservation measures, greener feed as well as low waste systems is urgently needed, to keep production activities within the carrying capacity of ecosystems. Coupled emergy and economic analyses can provide better insight into the environmental and economic benefits of fish production systems and help solve the problems encountered during policy making.     

Integrating emergy evaluation and geographic information systems for monitoring resource use in the Abruzzo region (Italy)

This paper presents an application of an environmental accounting method, namely emergy evaluation, developed for the monitoring and assessment of environmental resource use by local communities in the Abruzzo Region (Italy). Once quantified and classified according to their origin (renewable or non-renewable, local or external), emergy flows were elaborated through a geographic information system (GIS) that allowed us to represent their spatial distribution throughout the region. Outcomes took the form of patterns in which different emergy intensities, namely empower (unit: seJ yr^?1), were represented through a graduated grey-scale and visualized on a cartographic basis. The concentration of emergy flows, depending on the activity of local communities, showed variable levels of environmental load in different areas. In particular, spatial zones with homogeneous values of empower density (unit: seJ yr^?1 km^?2) – high, medium and low – were detected in order to identify areas with a similar “thermodynamic” nature, emergy being a thermodynamics based function. This allowed for the representation, at a glance, of a kind of geography that mirrors the behavior of a population settled in an area as additional information for investigating the effects of the use of urban structures and functions and improving our understanding of regional systems. A combined use of emergy evaluation and GIS could thus provide a complementary view of a territorial system and inform policy makers for planning specific strategies of future development.     

Measuring sustainability performance of local food production in home gardens

The growing interests in “local food” in recent years in public discussions, research and practice highlight its significant importance as a part of overall food system. This research compares spatially local food production potential of home gardens in nine residential neighbourhood case studies with varying physical densities at a local scale using geographic information systems and mathematical methods. This paper develops a “local food energy model” for measuring sustainability potential of growing local food mainly vegetables in the home gardens. The outcomes indicate that potential of the home gardens in supplying vegetables demand as a share of total dietary energy would depend on the morphological characteristics of urban forms, total resident population, total food demand and other related factors. Local food production in the home gardens could meaningfully contribute towards building a sustainable food future.     

A technical and investment analysis of intermediate-scale rice residue conversion systems

This paper describes the technical and economic factors affecting rice husk residue conversion to energy. A summary of the physical and chemical characteristics is provided, with an overview of the commercially available conversion systems. An analysis of two intermediate rice residue conversion systems is included to determine the most probable fuel requirements and financial/economic costs and benefits of both systems. Recommendations are presented regarding the conditions that must be present to ensure financial viability of these systems.     

基于能值分析的苏州市城市生态系统可持续发展评估

本文利用能值分析的方法,分析了苏州城市生态系统的各种生态流,并建立了苏州城市生态系统可持续发展能值评价指标体系,评估其可持续发展程度,并对其能值指标的发展进行了预测。研究结果显示,2007年苏州市系统利用总能值达到616.71×1021sej,能值自给率仅为35.5%,环境负载率达到61.67。与其他国家和地区能值指标对比得出,苏州市是一个高度外向型生态经济系统,其系统的发展高度依赖于外界资源的输入,面对现在不稳定的世界经济发展和外部环境,苏州市必须加大系统自身的供给能力,提高系统自身的稳定性;发展循环经济,降低系统环境负载率;加强高科技和人才投入,提高系统可持续发展潜力。     

Including Public Perspectives in Industrial Biotechnology and the Biobased Economy

Industrial (“white”) biotechnology promises to contribute to a more sustainable future. Compared to current production processes, cases have been identified where industrial biotechnology can decrease the amount of energy and raw materials used to make products and also reduce the amount of emissions and waste produced during production. However, switching from products based on chemical production processes and fossil fuels towards “biobased” products is at present not necessarily economically viable. This is especially true for bulk products, for example ethanol production from biomass. Therefore, scientists are also turning to genetic modification as a means to develop organisms that can produce at lower costs. These include not only micro-organisms, but also organisms used in agriculture for food and feed.The use of genetic modification for “deliberate release” purposes, in particular, has met great opposition in Europe. Many industrial biotechnology applications may, due to their scale, entail deliberate releases of GM organisms. Thus, the biobased economy brings back a familiar question; is it ethically justifiable, and acceptable to citizens, to expose the environment and society to the risks associated with GM, in order to protect that same environment and to sustain our affluent way of life? For a successful innovation towards a biobased economy, its proponents, especially producers, need to take into account (take responsibility for) such issues when developing new products and processes. These issues, and how scientists can interact with citizens about them in a timely way, are further explored in projects at Delft University and Leiden University, also in collaboration with Utrecht University.     

基于能值生态足迹的海岛可持续性评估——以舟山为例

基于能值理论,结合生态足迹方法,构建能值生态赤字/盈余、渔业足迹强度(D)、社会发展压力指数(I)和经济协调指数(Q)参数评价海岛可持续性,选取典型海岛城市浙江省舟山市作为案例研究。结果显示:2003—2017年舟山能值足迹、能值承载力均呈上升趋势;人均能值生态足迹共增加15.78 hm²,增幅为63.26%;人均能值承载力增加5.20×10² hm²,增幅为82.86%;其中,化石能源用地能值足迹增加最多,社会经济承载力增加最多,而自然承载力却有所下降。能值生态赤字/盈余和经济协调指数不能完全反映区域可持续性,区域渔业足迹强度的不断增加表明当前的渔业经济模式不满足可持续发展要求,社会发展压力指数增大也进一步表明舟山的发展状况偏离了可持续性的轨道。     

Critical Evaluation of How the Rosgen Classification and Associated “Natural Channel Design” Methods Fail to Integrate and Quantify Fluvial Processes and Channel Response1

Abstract: Over the past 10 years the Rosgen classification system and its associated methods of “natural channel design” have become synonymous to some with the term “stream restoration” and the science of fluvial geomorphology. Since the mid 1990s, this classification approach has become widely adopted by governmental agencies, particularly those funding restoration projects. The purposes of this article are to present a critical review, highlight inconsistencies and identify technical problems of Rosgen’s “natural channel design” approach to stream restoration. This paper’s primary thesis is that alluvial streams are open systems that adjust to altered inputs of energy and materials, and that a form‐based system largely ignores this critical component. Problems with the use of the classification are encountered with identifying bankfull dimensions, particularly in incising channels and with the mixing of bed and bank sediment into a single population. Its use for engineering design and restoration may be flawed by ignoring some processes governed by force and resistance, and the imbalance between sediment supply and transporting power in unstable systems. An example of how C5 channels composed of different bank sediments adjust differently and to different equilibrium morphologies in response to an identical disturbance is shown. This contradicts the fundamental underpinning of “natural channel design” and the “reference‐reach approach.” The Rosgen classification is probably best applied as a communication tool to describe channel form but, in combination with “natural channel design” techniques, are not diagnostic of how to mitigate channel instability or predict equilibrium morphologies. For this, physically based, mechanistic approaches that rely on quantifying the driving and resisting forces that control active processes and ultimate channel morphology are better suited as the physics of erosion, transport, and deposition are the same regardless of the hydro‐physiographic province or stream type because of the uniformity of physical laws.     

Ecological and economic dynamics of the Shunde agricultural system under China's small city development strategy

The agricultural and industrial development of small cities is the primary environmental management strategy employed to make full use of extra labor in the rural areas of China. The ecological and economic consequences of this development strategy will affect over 100 million people and change the organization of the Chinese landscape. In this study, we examined the agricultural development of Shunde, a small city in Guangdong Province, over the period 1978 until 2000. Our analysis of the ecological and economic dynamics of the agricultural system revealed the dominant role of labor in the intensification of agricultural production, even though the use of fuels, fertilizers and machines also increased during this time. The Shunde agricultural system was examined from both biophysical or donor-based and human utility or receiver-based perspectives, using emergy and economic methods, respectively. After 22 years of urbanization, the Shunde agricultural system was still able to fill 96% of the local demand for agricultural products using only 6% of its total yield compared to using 14% of the total yield in 1978. Aquaculture developed quickly during the study period as grain production decreased. In 2000, the production of fish, pork, and vegetables accounted for 92% of the total emergy output of the system; however, the emergy buying power of the money received in exchange was lower than the emergy contained in the products exported. The excess emergy exported is the basis for a high quality diet delivered to city dwellers at a relatively low price. In the 1980s, the productivity of both land and labor increased; but after 1992 the productivity of labor decreased, causing the efficiency of the whole agricultural system to decrease. We recommend that processing plants be established for the main agricultural products of Shunde to decrease the emergy loss in trading and to increase employment. The effect of including monetized ecosystem services in the balance between the emergy delivered to the markets in agricultural products and the emergy buying power of the money received was to decrease the emergy gained by the Shunde agricultural system.     

Energy and resource basis of an Italian coastal resort region integrated using emergy synthesis

Sustainable development of coastal zones must balance economic development that encourages human visitation from a larger population with desires that differ from the local residents with the need to maintain opportunities for the local resident society and conserve ecological capital, which may serve as the basis for residents.We present a case study in which the sustainability level of a coastal zone (Riviera del Beigua), located along the Ligurian coast of north-western Italy, was assessed through the lens of systems ecology using emergy synthesis to integrate across economic, social and environmental sub-systems.Our purposes were (1) to quantify the environmental sustainability level of this coastal zone, (2) to evaluate the role of tourism in affecting the economy, society and environment, and (3) to compare emergy synthesis to Butler's Tourism Area Life Cycle model (TALC). Results showed that 81% of the total emergy consumption in the coastal zone was derived from external sources, indicating that this tourist-heavy community was not sustainable. Tourism, as the dominant economic sub-system, consumed 42% of the total emergy budget, while local residents used the remaining 58%. The progressive stages of the TALC model were found to parallel the dynamic changes in the ratio of external emergy inputs to local emergy inputs, suggesting that emergy synthesis could be a useful tool for detecting a tourist region's TALC stage. Use of such a quantitative tool could expedite sustainability assessment to allow administrative managers to understand the complex relationship between a region's economy, environment and resident society so sound policies can be developed to improve overall sustainability.     

Energy and other resource conservation within urbanizing areas

The reported research seeks to answer several questions regarding energy conservation within urbanizing areas. As a practical matter, to what extent can dependence upon exhaustible resources be reduced? Can these reductions be achieved without severely impairing social well-being and environmental quality? And, what seem to be the prevailing institutional constraints limiting energy conservation within urbanizing areas? The study area was the proposed “downtown” of The Woodlands, a new town north of Houston, Texas. Two plans were developed for this area. In one, no particular attempt was made to conserve energy (conventional plan), while in the other, energy conservation was a primary consideration (conservation plan). For both plans, estimates were made of energy consumption within buildings, in the transportation sector, and in the actual production of building materials themselves (embodied energy). In addition, economic and environmental analyses were performed, including investigation of other resource issues such as water supply, solid waste disposal, stormwater management, and atmospheric emissions. Alternative on-site power systems were also investigated. Within the bounds of economic feasibility and development practicality, it was found that application of energy-conserving methods could yield annual energy savings of as much as 23%, and reduce dependence on prime fuels by 30%. Adverse economic effects on consumers were found to be minimal and environmental quality could be sustained. The major institutional constraints appeared to be those associated with traditional property ownership and with the use of common property resources. The resistance to change of everyday practices in land development and building industries also seemed to constrain potential applications.     

Spatial assessment of the economic feasibility of short rotation coppice on radioactively contaminated land in Belarus, Ukraine, and Russia. I. Model description and scenario analysis

The economic feasibility of short rotation coppice (SRC) production and energy conversion in areas contaminated by Chernobyl-derived (137)Cs was evaluated taking the spatial variability of environmental conditions into account. Two sequential GIS-embedded submodels were developed for a spatial assessment, which allow for spatial variation in soil contamination, soil type, and land use. These models were applied for four SRC production and four energy conversion scenarios for the entire contaminated area of Ukraine, Belarus, and Russia and for a part of the Bragin district, Belarus. It was concluded that in general medium-scale SRC production using local machines is most profitable. The areas near Chernobyl are not suitable for SRC production since the contamination levels in SRC wood exceed the intervention limit. Large scale SRC production is not profitable in areas where dry and sandy soils predominate. If the soil contamination does not exceed the intervention limit and sufficient SRC wood is available, all energy conversion scenarios are profitable.     

Farmers’ Attitude Towards Animal Welfare Aspects and Their Practice in Organic Dairy Calf Rearing: a Case Study in Selected Nordic Farms

In organic philosophy, the concept of “naturalness” is of major importance. According to the organic interpretation of animal welfare, natural living is considered a precondition for accomplishing welfare and the principal aims of organic production include the provision of natural living conditions for animals. However, respective regulations are lacking in organic legislation. In practice, the life of a calf in organic rearing systems can deviate from being natural, since common practices in dairy farms include early weaning, dehorning, or cow-calf separation soon after birth. This case study explores how calf welfare is approached in six different organic dairy farms and how far the concept of naturalness is implemented. The farms included in this study were located in Norway and Sweden. A semi-structured questionnaire was used for data collection. The interviewed farmers approach the concept of welfare in various ways and state that “naturalness” is an aspect of animal welfare. However, in practice in the calf rearing systems under study, only a few “naturalness” aspects were implemented. Reasons for the observed discrepancy might lie in differing understandings of “naturalness,” in economic restrictions, and in other trade-offs resulting from production system inherent characteristics and in limited regulation concerning provision of natural living aspects.     

Dynamic emergy evaluation of a fish farm rearing process

The environmental sustainability of a fish farm rearing process was examined by means of emergy analysis. Many emergy analyses integrate data for a whole year smoothing short term variations and sometimes losing meaningful information (aliasing). For this reason we developed a model for an instantaneous emergy evaluation in an aquacultural system so that transformities, efficiency and effort spent at each moment during the fish rearing activity could be calculated. By means of the model and dynamic emergy calculations it is possible to recognize step by step the importance of the various emergy contributions and verify where and when to modify the system to move toward optimum production of a sustainable product. By the application of the model we confirmed that the emergy trends in a fish farm installation follow wide oscillations during a year due to variations in both internal and external emergy contributions. Among the fluxes considered, those due to the introduction of fingerlings represented the highest contributions to the total emergy budget. Thus, to improve the sustainability of the analyzed system the amount, frequency and timing of these fluxes must be carefully considered. For this purpose, a comparison between two different fry introduction schedules was performed to evaluate differences in the efficiency of the rearing process.     

Advancing Sustainable Bioenergy: Evolving Stakeholder Interests and the Relevance of Research

The sustainability of future bioenergy production rests on more than continual improvements in its environmental, economic, and social impacts. The emergence of new biomass feedstocks, an expanding array of conversion pathways, and expected increases in overall bioenergy production are connecting diverse technical, social, and policy communities. These stakeholder groups have different—and potentially conflicting—values and cultures, and therefore different goals and decision making processes. Our aim is to discuss the implications of this diversity for bioenergy researchers. The paper begins with a discussion of bioenergy stakeholder groups and their varied interests, and illustrates how this diversity complicates efforts to define and promote “sustainable” bioenergy production. We then discuss what this diversity means for research practice. Researchers, we note, should be aware of stakeholder values, information needs, and the factors affecting stakeholder decision making if the knowledge they generate is to reach its widest potential use. We point out how stakeholder participation in research can increase the relevance of its products, and argue that stakeholder values should inform research questions and the choice of analytical assumptions. Finally, we make the case that additional natural science and technical research alone will not advance sustainable bioenergy production, and that important research gaps relate to understanding stakeholder decision making and the need, from a broader social science perspective, to develop processes to identify and accommodate different value systems. While sustainability requires more than improved scientific and technical understanding, the need to understand stakeholder values and manage diversity presents important research opportunities.     

Emergy accounting of the Province of Siena: towards a thermodynamic geography for regional studies

This research is part of the SPIn-Eco project for the Province of Siena, Italy, and applies an environmental accounting method to a region with reference to its population, human activities, natural cycles, infrastructures and other settings. This study asserts that the consumption of resources due to the human economy is a source of great concern because of the load it places on the biosphere. Environmental resources locally used, whether directly or indirectly, from both renewable energy fluxes and storage of materials and energies, are investigated. In this paper emergy analysis is presented and applied to the Province of Siena and to each of its municipalities, in order to evaluate the main flows of energy and materials that supply the territorial system, including human subsystems, with reference to their actual environmental cost. Therefore, the behaviour of the whole system and the interactions between natural and human agents were studied; in other words, the attitudes of the territorial systems toward resource use as revealed by their patterns of emergy consumption were observed. Once expressed in units of the same form of energy through the emergy evaluation, categories of resource consumption and systems of varying scales and organization are compared. Furthermore, indexes of environmental performance based on emergy are calculated. Flows of energy and materials are assessed, and their intensities, which vary throughout the area of the Province, are then visualized on maps.     

Spatial assessment of the economic feasibility of short rotation coppice on radioactively contaminated land in Belarus, Ukraine, and Russia. II. Monte Carlo analysis

A Monte Carlo analysis of two sequential GIS-embedded submodels, which evaluate the economic feasibility of short rotation coppice (SRC) production and energy conversion in areas contaminated by Chernobyl-derived (137)Cs, was performed to allow for variability of environmental conditions that was not contained in the spatial model inputs. The results from this analysis were compared to the results from the deterministic model presented in part I of this paper. It was concluded that, although the variability in the model results due to within-gridcell variability of the model inputs was considerable, the prediction of the areas where SRC and energy conversion is potentially profitable was robust. If the additional variability in the model input that is not contained in the input maps is also taken into account, the SRC production and energy conversion appears to be potentially profitable at more locations for both the small scale and large scale production scenarios than the model predicted using the deterministic model.     

基于能值分析的山区县域经济可持续发展评价——以吉林省抚松县为例

选取吉林省抚松县为研究区域，采用能值分析方法，从生态安全、经济发展、社会接受方面建立评价指标体系，对吉林省抚松县生态经济系统进行定量和定性评价。研究结果表明：①2005--2009年抚松县生态经济系统能值投入量和能值产出量均呈增加态势，能值投入以本地资源为主，工业产值迅速增加（以林产品为主），而农产品产值持续减少。②抚松县经济发展水平在全国、全省范围内均属于较低水平，工业发展效率很低，居民生活质量不高。③生态环境压力逐年增大，主要原因是自然资源的大规模开发，但是与其他发达地区、我国西部地区相比，抚松县在生态环境承载力方面仍具有相对优势。据此，提出了通过大力发展旅游产业、绿色食品、林产品的深加工等增强系统开放性，深入挖掘优势资源的高价值形态，以达到山区县域经济的可持续发展。     

Real‐Time Analysis of Energy Generation of a Photovoltaic System Installed in the City of Lajeado,Rio Grande do Sul

Considering successive and costly increases in electricity rates, this article evaluates the generation of electricity from a photovoltaic system using solar energy, a renewable source. The solar photovoltaic system is installed at UNIVATES University Center, a public university in the state of Rio Grande do Sul, Brazil, and it is also connected to the electrical grid. Data related to the climatic conditions of the location, such as incident solar radiation, rainfall, and mean temperature, were obtained during the system's evaluation period and used along with bibliographic research on similar systems installed in southern Brazil. Our study quantified the energy produced over one calendar year (2014) and related it to the climatic variables and the conversion efficiency achieved by the system's photovoltaic modules. Our results show that there is both a strong relationship between the production of energy and climatic conditions and that the city, Lajeado, and the Brazilian state of Rio Grande do Sul, have good potential to supply energy using photovoltaic systems connected to the electrical grid. The horizontal global solar radiation average obtained in the study location was 4.14 kilowatts per square meter per day (kWh/m²/day), and the average monthly production of energy reached 243.93 kWh/m²/month, with a total of 2,927.10 kWh produced in 2014, achieving a monthly average conversion efficiency of 11.07%. This conversion efficiency is close to the value of 12.6% obtained in 2013 in a similar study of the same solar photovoltaic system conducted over a shorter time period.