Development and optimization of an Agro-BGC ecosystem model for C4 perennial grasses

Extrapolating simulations of bioenergy crop agro-ecosystems beyond data-rich sites requires biophysically accurate ecosystem models and careful estimation of model parameters not available in the literature. To increase biophysical accuracy we added C₄ perennial grass functionality and agricultural practices to the Biome-BGC (BioGeochemical Cycles) ecosystem model. This new model, Agro-BGC, includes enzyme-driven C₄ photosynthesis, individual live and dead leaf, stem, and root carbon and nitrogen pools, separate senescence and litter fall processes, fruit growth, optional annual seeding, flood irrigation, a growing degree day phenology with a killing frost option, and a disturbance handler that simulates nitrogen fertilization, harvest, fire, and incremental irrigation. To obtain spatially generalizable vegetation parameters we used a numerical method to optimize five unavailable parameters for Panicum virgatum (switchgrass) using biomass yield data from three sites: Mead, Nebraska, Rockspring, Pennsylvania, and Mandan, North Dakota. We then verified simulated switchgrass yields at three independent sites in Illinois (IL). Agro-BGC is more accurate than Biome-BGC in representing the physiology and dynamics of C₄ grass and management practices associated with agro-ecosystems. The simulated two-year average mature yields with single-site Rockspring optimization have Root Mean Square Errors (RMSE) of 70, 152, and 162 and biases of 43, −87, 156 g carbon m⁻² for Shabbona, Urbana, and Simpson IL, respectively. The simulated annual yields in June, August, October, December, and February have RMSEs of 114, 390, and 185 and biases of −19, −258, and 147 g carbon m⁻² for Shabbona, Urbana, and Simpson IL, respectively. These RMSE and bias values are all within the largest 90% confidence interval around respective IL site measurements. Twenty-four of twenty-six simulated annual yields with Rockspring optimization are within 95% confidence intervals of Illinois site measurements during the mature fourth and fifth years of growth. Ten of eleven simulated two-year average mature yields with Rockspring optimization are within 65% confidence intervals of Illinois site measurements and the eleventh is within the 95% confidence interval. Rockspring optimized Agro-BGC achieves accuracies comparable to those of two previously published models: Agricultural Land Management Alternatives with Numerical Assessment Criteria (ALMANAC) and Integrated Farm System Model (IFSM). Agro-BGC suffers from static vegetation parameters that can change seasonally and as plants age. Using mature plant data for optimization mitigates this deficiency. Our results suggest that a multi-site optimization scheme using mature plant data from more sites would be adequate for generating spatially generalizable vegetation parameters for simulating mature bioenergy crop agro-ecosystems with Agro-BGC.     

Threshold management in a coupled economic–ecological system

Economic analysis of optimal ecosystem management in the presence of a threshold has typically ignored the potential for induced behavioral responses. This paper contributes to the literature on non-convex ecosystem management by considering the implications of a particular behavioral response in a regional economy – that of amenity-led growth – to changes in ecosystem services generated by a lake ecosystem subject to a eutrophication threshold. The essential policy challenge is to achieve optimal levels of lake nutrients and urbanization given that improvements to water quality will induce additional migration and urbanization in the region with attendant ecological impacts. We show that policies that ignore the recursive relationship between urbanization and water quality unintentionally exacerbate boom-bust cycles of regional growth and decline and risk pushing the system towards long-run economic decline. In contrast, the optimal policy accounts for the behavioral feedbacks to improved ecosystem services, and balances regional growth and ecological degradation.     

Performance evaluation of process industries resilience: Risk-based with a network approach

Risk management can be defined as coordinated activities to conduct and control an organization with consideration of risk. Recently, risk management strategies have been developed to change the approach to hazards and risks. Resilience as a safety management theory considers the technical and social aspects of systems simultaneously. Resilience in process industries, as a socio-technical system, has four aspects of early detection, error-tolerant design, flexibility, and recoverability. Meanwhile, process industries' resilience has three phases: avoidance, survival, and recovery, determining the transition between normal state, process upset event, and catastrophic event. There may be various technical and social failures such as regulatory and human or organizational items that can lead to upset or catastrophic events. In the avoidance phase, the upset event is predicted, and thus, the system remains in a normal state. For the survival phase, the system state is assumed to be an upset process event, and the system tries to survive through the unhealthy process conditions or remains in the same state, probably with low performance. In the recovery phase, the system is supposed to be catastrophic, and the emergency barriers are prioritized to show the severity of the consequences and response time, leading to a resumption of a normal state. Therefore, a resilience-based network can be designed for process industries to show its inherent dynamic transition in nature. In this study, network data envelopment analysis (DEA), as a mathematical model, is used to evaluate the relative efficiency of the process industries regarding a network transition approach based on the system's internal structure. First, a resilience-based network is designed to consist of three states of normal, upset, and catastrophic events. Then, the efficiency of each industrial department, which is defined as decision-making units (DMUs), is evaluated using network DEA. As a case study, a refinery that is considered a critical process industry is assessed. Using the proposed model shows the efficient and inefficient DMUs in each of three states of normal, upset, and catastrophic events of the process and the projection onto efficient frontiers. Besides calculating the network efficiency, the performance of each state is extracted to precisely differentiate between DMUs. The results of this study, which is one of the fewest cases in the area of performance evaluation of process industries with a network approach, indicated a robust viewpoint for monitoring and assessment of risks.     

Regional Research Capacity-Building in Sustainability Science: Facts,Gaps, and Futures in Northeast Asia

Abstract

Evidence shows that some conceptual ideas relevant to both local and global sustainability have been adopted in some official documents in northeast Asian nations, particularly China, South Korea, and Japan. This seems to be a very positive signal for the future development of sustainability science in this region. However, studyes show that there are still some major gaps there. One is the problem of how to build up the regional research capacity of sustainability science among northeast Asian research institutes across different disciplines as well as different political systems. Another is how to shift the conceptual frameworks of sustainability science into the operational policy frameworks. There are four major obstacles to the enhancement of regional research capacity-building in sustainability science. In order to build up the regional research capacity in sustainability science and to realize both local and global goals of the sustainable development in northeast Asia, this paper proposes some basic frameworks, including regional institutional innovations, establishment of a regional sustainability information network, initiatives of the regional assessment programme, and focus on the regional education and training of sustainability knowledge.     

中国地区经济差距及其演化的产业变动因素

20世纪90年代以来中国地区经济差距扩大具有深刻的产业变动原因。以人均GDP为基本指标,通过对基尼系数进行产业分解和对泰尔指数进行地区分解,深刻分析了1990~2004年中国地区经济差距的动态变化、地区构成和产业构成,揭示了中国地区经济差距及其演变的产业结构变动与产业地区集中因素。结果表明,1990年以来中国地区经济差距的决定性因素是第二产业发展水平的地区差距,而非农产业向东部沿海地区的集中又是推动中国地区经济差距扩大的主导性因素。20世纪90年代以来,随着以制造业为主的非农产业向东部沿海地区集中,中西部地区逐渐沦落为以农业与采掘业为主的外围区域,中国的地区经济差距也由此持续扩大。基于此,认为缩小地区差距的关键是推进中西部地区制造业发展,缓解非农产业地区分布的不平衡状况。     

Challenges in radioecology

Today, radioecology covers a broad scientific field; from the source to long term environmental impact from ionizing radiation. To summarize key challenges within radioecology, the present paper focuses upon knowledge gaps related to processes, mechanisms and variables contributing most to the overall uncertainties in environmental impact assessments. A series of sources related to the nuclear weapon cycle and the civil nuclear cycle has contributed, is still contributing or can potentially contribute to release of radionuclides to the environment in the future. The speciation of most radionuclides depends on the source and release conditions, and will influence ecosystem transport, biological uptake, doses and effects in flora and fauna. Radionuclides may also co-occur in contaminant mixtures (e.g., metals, organics), which potentially could lead to synergisms or antagonisms. Thus, challenges associated with the links between the source or release term – radionuclide speciation – ecosystem transfer – exposure – response relationships are highlighted.     

Challenging the current strategy of radiological protection of the environment: arguments for an ecosystem approach

The system of radiological protection of the environment that is currently under development is one contribution to the general need to adequately protect the environment against stress. Dominated by operational goals, it emphasizes conceptual and methodological approaches that are readily accessible today: reference organisms supported by individual-based traditional ecotoxicological data. Whilst there are immediate advantages to this approach (pragmatism, consistency with other approaches in use for man and biota), there are also clear limitations, especially in a longer run perspective, that need to be acknowledged and further considered. One can mention a few: uncertainties generated by the need for various extrapolations (from lower to higher levels of biological organisation, …), various features missed such as potential ecological impact through impairment of ecosystem processes, trans-generational impacts as mediated through genomic instability, indirect effects mediated through trophic interactions or disruption of ecological balances,… Such limitations have already been faced in other fields of environmental protection against other stressors, pushing a number of environment professionals to assign stronger emphasis on more systemic approaches. This review discusses the advantages and limitations of the current approach designed for the radiological protection of non-human biota in the broader context of environment protection as a whole, with especial reference to upcoming trends and evolutions. This leads in particular to advocating the need to boost scientific and methodological approaches featuring the ecosystem concept as a mean to access a unified goal of protection: preserving life sustainability through protection of ecosystem structure and functioning.     

环境规制对技术效率和生产力损失的影响分析

以中国工业为研究对象,以经济发展程度不同所分的东部、中部和西部地区兰个地区作为研究区域,采用非参数数据包络法(DEA)中的径自效率测量方法(radial efficiency measure)为主要研究方法,分析了在1998-2005年期间环境规制对中国工业的技术效率和生产力损失的影响.研究结果表明,在指定的研究期间,环境规制使得中国工业技术效率提高,但是对于生产力的发展却产生了负面的影响.三个地区之间受环境规制影响的差异较大,其中东部为环境规制所付出的成本最大,即东部为环境污染所付出的环境成本最高,这也是为何从九十年代开始,污染物从东部往中西部转移的原因;从受污染物影响的角度来看,因控制废水而引起的生产力损失大于因控制SO2而引起的生产力损失,即对于中国工业,废水的环境成本大于SO2的环境成本.另外,从研究结果中也可知,在中国现有的生产方式下,实施严格的环境规制有一定难度,所以改变旧的生产方式,实施可持续发展的生产方式是当务之急.     

A mapping of global warming research based on IPCC AR4

It is easy to get lost in the vast amount of knowledge that is currently produced. In this study, to get a comprehensive picture of current scientific knowledge about global warming issues, we developed a mapping framework for global warming research based on the relationships between nature and human society. The mapping includes seven phases: (1) socioeconomic activity and greenhouse gas emissions, (2) carbon cycle and carbon concentration, (3) climate change and global warming, (4) impacts on ecosystems and human society, (5) adaptation, (6) mitigation, and (7) social systems. We applied the findings of the Intergovernmental Panel on Climate Change Fourth Assessment Report to the mapping. The quantity of research results and their reliability were analyzed on the basis of expert judgment to better understand the extent to which current scientific knowledge provides answers to society’s major concerns. The quantity and reliability of answers have increased in phases 2 and 3 relative to research in the Third Assessment Report. Although a large quantity of results have been produced in phases 4 and 6, they are not always sufficient. More studies are required in phases 1, 5, and 7, and the reliability of existing knowledge needs to be improved in these phases. Mapping global warming issues enabled us to visually comprehend the numerous and varied parts of global warming research as a whole and to discern gaps in knowledge and other research shortfalls. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Accounting for the mismanagement of tropical nearshore fisheries

The underlying reason for the mismanagement of tropical nearshore fisheries is the implementation of policies and programs based on Western models and approaches, coupled with an inability and/or unwillingness to consider non-Western alternatives of empirically proven value. Such attitudes are embedded in donor and development agency behavior, and are demonstrated by the temperate bias in conventional approaches to fisheries education and management, with a corresponding lack of understanding of tropical milieux, and in the persistence of various prejudices. Adaptive Management, The Ecosystem Approach, Local Knowledge, and Protected Areas are discussed from the perspectives of Western models and pre-existing Pacific Island systems as alternative models. Given the parlous condition of the global environment and resources, the best non-Western pre-existing models and Western approaches must be blended to provide sustainable solutions.