Detecting and Coping with Disruptive Shocks in Arctic Marine Systems: A Resilience Approach to Place and People

It seems inevitable that the ongoing and rapid changes in the physical environment of the marine Arctic will push components of the region’s existing social-ecological systems—small and large—beyond tipping points and into new regimes. Ongoing changes include warming, freshening, acidification, and alterations to food web structure. In anticipation we pose three distinct but interrelated challenges: (1) to explore existing connectivities within components of the marine system; (2) to seek indicators (if they exist) of approaching regime change through observation and modeling; and (3) to build functional resilience into existing systems through adaptation-oriented policy and to have in hand transformative options when tipping points are crossed and new development trajectories are required. Each of the above challenges is scale dependent, and each requires a much deeper understanding than we currently have of connectivity within existing systems and their response to external forcing. Here, we argue from a global perspective the need to understand the Arctic’s role in an increasingly nonlinear world; then describe emerging evidence from new observations on the connectivity of processes and system components from the Canada Basin and subarctic seas surrounding northern North America; and finally posit an approach founded in “resilience thinking” to allow northern residents living in small coastal communities to participate in the observation, adaption and—if necessary—transformation of the social-ecological system with which they live.     

Tipping Toward Sustainability: Emerging Pathways of Transformation

This article explores the links between agency, institutions, and innovation in navigating shifts and large-scale transformations toward global sustainability. Our central question is whether social and technical innovations can reverse the trends that are challenging critical thresholds and creating tipping points in the earth system, and if not, what conditions are necessary to escape the current lock-in. Large-scale transformations in information technology, nano- and biotechnology, and new energy systems have the potential to significantly improve our lives; but if, in framing them, our globalized society fails to consider the capacity of the biosphere, there is a risk that unsustainable development pathways may be reinforced. Current institutional arrangements, including the lack of incentives for the private sector to innovate for sustainability, and the lags inherent in the path dependent nature of innovation, contribute to lock-in, as does our incapacity to easily grasp the interactions implicit in complex problems, referred to here as the ingenuity gap. Nonetheless, promising social and technical innovations with potential to change unsustainable trajectories need to be nurtured and connected to broad institutional resources and responses. In parallel, institutional entrepreneurs can work to reduce the resilience of dominant institutional systems and position viable shadow alternatives and niche regimes.     

A multi-approach strategy in climate attribution studies: Is it possible to apply a robustness framework?

Attribution studies investigate the causes of recent global warming. For a few decades the scientific community generally adopted dynamical models – the so-called Global Climate Models (GCMs) – for such an investigation. These models show the essential role of anthropogenic forcings in driving the temperature behaviour of the last half century. In the last period even other (data-driven) methodological approaches were adopted for attribution studies. This allows the scientific community to compare the results coming from these different approaches and to possibly increase their robustness. For such a purpose, the paper explores the possibility of applying a robustness framework, so far used only in the case of multi-model GCM ensembles, to a strategy including models from different methodological orientations, assessing such an application especially in the light of the independence issue.     

中国工业系统各行业综合污染度评价方法与实例

中国的环境问题很大程度上与高强度和低效益的工业经济活动有关.降低工业系统污染程度无疑对我国建设资源节约型和环境友好型社会具有重要意义.对工韭系统各行业污染度进行定量化的综合评价,得到单一化的污染度指数,可方便不同行业间清洁水平的比较,可为各地区工业布局和工业结构的调整提供理论依据.本文初步建立了中国工业系统污染度综合评价的方法,并对栽"十五"期间(2001-2005)我国重点调查的41个工业行业的综合污染度进行了评价,得到了各行业的综合污染度评价指数、排名及其变化情况.结果表明,"十五"期间,我国工业系统污染度总体上有较大幅度的降低,各行业污染度差别较大,有的行业污染度有大幅下降,有的行业还有所增加.本文的研究成果可为建设资源节约型和环境友好型社会提供重要理论支持.     

Food risks and the environment: changing perspectives in a changing social order

Risks related to food production and consumption are not a recent phenomenon. Through agricultural practices, the transport of agricultural and food products, the processing of food, its storage, and finally the consumption of food, risks have been externalized, mediated, contested and ingested. But agrofood systems have also been paralleled by routinized practices and institutions that attempt to reduce risks and sustain trust among the many actors involved in these food regimes. However, both the (definition of) food risks and the institutions and discourses used to dispel anxiety and build trust are far from stable throughout time. In the contemporary modern world-order, food risks and the practices and institutions dealing with these risks reflect the significant transformations in the agrofood system, the changing nature of the risks involved in food production and consumption, and the modifications in scientific risk assessment and risk management. This article provides an overview of the current debates, discussions and practices on actual and potential institutional transformations that parallel the emergence, assessment and management of food risks in reflexive modernity. Copyright © 2002 John Wiley & Sons, Ltd.     

太湖流域农村生活污水处理技术探讨

2010年江苏省太湖流域主要污染物排放情况显示,太湖流域内的农村生活污水、农田径流和养殖污水是导致太湖水体富营养化的主要污染源。目前,在中国针对农村生活污水的处理技术已有一定研究。根据太湖流域农村生活污水的特点,人工湿地处理技术和稳定塘系统等新型污水处理技术具有良好的应用前景。     

基于蝴蝶突变理论的企业安全生产保障系统危险程度四维分析模型

利用蝴蝶型突变建立人、物、管理、环境安全生产保障模型，人、物、管理、环境的权重与四个控制变量各自相乘，就可能构成了更具有代表和全面含义新突变级数。新突变级数乘于各自单位向量，得出四维控制变量，为在四维空间上分析企业的安全生产危险程度的临界点提供了新的思路。建立蝴蝶型突变理论的在安全决策模型，将企业的安全生产危险程度分为：理想的安全区域；危险区域；相对的安全区域，蝴蝶型突变理论能够揭示企业的安全状况。     

Rangeland dynamics in southern Ethiopia: (1) botanical composition of grasses and soil characteristics in relation to land-use and distance from water in semi-arid Borana rangelands

The distribution and compositional pattern of the grass layer, as well as soil quality of southern Ethiopian semi-arid rangelands were examined under three land-use systems (communal land, government ranch and a traditional grazing reserve enclosure) and along a distance gradient (near, middle and far) from water sources. In total, 49 grass species were identified, 65% of which were perennials. Of the most commonly distributed highly desirable species, Chrysopogon aucheri showed the greatest frequency under the traditional grazing reserve (27.6%), and the lowest in the communal land (14.0%). The frequency of Cenchrus ciliaris was similar in all the study sites. The proportion of Lepthotrium senegalensis was low under the land-use systems (3.9%) and increased away from water sources (2.3%). Of the less desirable species, Sporobulus nervosus was extremely more abundant (<0.05) in the communal land (13.3%) than the traditional grazing reserve (3.3%) and the government ranch (1.9%). Sporobolus pyramidalis was dominant in the study sites, with similar (P>0.05) frequency percentages under the land-use systems and along the distance gradients from water. Basal cover was low and similar on all the study sites (3.3%). Concerning the soil texture, sand (71.1%) constituted the largest proportion, followed by silt (21.3%) and lastly, clay (7.7%). With regard to soil exchangeable cations, organic C and total nitrogen were generally low and did not show marked variation in all the study sites. The study showed significant differences for most of the vegetation variables between the communal land and the other land-uses. This suggested that grazing intensity was higher in the communal land and moderate in the government ranch and in the traditional grazing reserves (kallos). The lack of significant differences in most of the studied (vegetation) variables along the distance gradient from water could be ascribed to the fact that grazing disturbance has already exceeded a certain threshold of degradation. Under the present low states of soil nutrients and rainfall, cultivation is neither sustainable nor environmentally friendly and this will lead to further degradation of the soil in these marginal lands.     

Deteriorated watersheds can be restored: A case study

A project in west-central Colorado demonstrated that a watershed dissected by a dense gully network can be stabilized and rehabilitated. Check dam systems, aided by improved vegetative cover through reduced cattle grazing and plantings, stabilized not only the structurally treated gullies, but also gullies within the network that were not structurally treated. Comparison with untreated gullies located outside of the project area, showed that the outside gullies widened three times as much as the structurally untreated inside gullies. Statistical analysis indicated that precipitation was normal during the treatment and evaluation period.Check dams decreased gully depth by accumulating sediment deposits. In turn, gully bank stabilization was hastened and alluvial aquifer volumes increased. This increase, plus higher infiltration rates as a result of denser vegetation, led to renewed perennial streamflow after 7 treatment years.Within 11 years after treatment, check dam systems and improved vegetation reduced sediment loads in the flows by more than 90 percent, providing a substantial benefit to farmlands and ponds downstream.From this work we are able to conclude that only part of a gully network requires structural treatment. The mainstem gully, and those tributaries controlling the local base levels of others, are the critical segments that should be structurally treated.     

Local recycling of plant nutrients from small-scale wastewater systems to farmland—A Swedish scenario study

Reducing the negative impact from on-site systems and promoting recycling are important tasks for municipal authorities, especially as regards phosphorus. The objective of this scenario study was to compare energy turnover in a life cycle perspective, recycling potential and expected reduction of nitrogen and phosphorus emissions for three upgraded small-scale wastewater systems based on local recycling of plant nutrients. The systems studied were urine separation, blackwater separation and chemical precipitation in the septic tank. The urine was sanitised through storage, the blackwater through liquid composting and the precipitated sludge through chemical treatment with urea before reuse in agriculture. The system boundaries included the operational phase as well as investment in capital goods required for upgrading the existing on-site systems.The urine separation system used least energy. The potential recycling and reduction of phosphorus was lower than for the other two systems, while that of nitrogen was higher than for the chemical precipitation system but lower than for the blackwater separation system. The blackwater separation system reduced both nitrogen and phosphorus to a high extent and also enabled a large proportion of both nitrogen and phosphorus to be recycled to arable land. However, a major drawback with this system was its significantly higher use of electricity, related to the aeration and stirring required when sanitising the blackwater by liquid composting. When urea treatment replaced liquid composting, the use of electricity decreased substantially in the blackwater separation system. The chemical precipitation system was efficient in reducing and recycling phosphorus, while inefficient for nitrogen. The use of fossil fuels was significantly higher than for the other two systems, primarily due to the production of the precipitation chemical.