A perspective on radical transformations to sustainability: resistances,movements and alternatives

A transformation to sustainability calls for radical and systemic societal shifts. Yet what this entails in practice and who the agents of this radical transformation are require further elaboration. This article recenters the role of environmental justice movements in transformations, arguing that the systemic, multi-dimensional and intersectional approach inherent in EJ activism is uniquely placed to contribute to the realization of equitable sustainable futures. Based on a perspective of conflict as productive, and a “conflict transformation” approach that can address the root issues of ecological conflicts and promote the emergence of alternatives, we lay out a conceptual framework for understanding transformations through a power analysis that aims to confront and subvert hegemonic power relations; that is, multi-dimensional and intersectional; balancing ecological concerns with social, economic, cultural and democratic spheres; and is multi-scalar, and mindful of impacts across place and space. Such a framework can help analyze and recognize the contribution of grassroots EJ movements to societal transformations to sustainability and support and aid radical transformation processes. While transitions literature tends to focus on artifacts and technologies, we suggest that a resistance-centred perspective focuses on the creation of new subjectivities, power relations, values and institutions. This recenters the agency of those who are engaged in the creation and recuperation of ecological and new ways of being in the world in the needed transformation.     

Identifying land suitable for agricultural land reform using GIS-MCDA in South Africa

Land reform is identified as a key tool in fostering development in South Africa. Twenty years after the advent of democracy in South Africa, the land question remains a critical issue for policy makers. Several frameworks have been put in place by the government to identify land that is strategically located for land reform. However, many of these frameworks are not well aligned and not objective in defining strategically located land for land reform and often lead to unsustainable land use management practices. This has hampered the government’s land reform initiative in promoting agricultural land reform and food security. Accordingly, there is a need to develop a decision support tool that facilitates the identification of strategically located land for land reform. This study proposes the use of geographic information systems (GIS) and multi-criteria decision analysis (MCDA) to develop a strategically located land index (SLLI) to identify land suitable for agricultural land reform. Participatory workshops and the group analytical hierarchy process were utilised to identify and weigh criteria used in computing the SLLI. The results indicate that land that is suitable for agricultural land reform is scarce, and there are also competing needs on the highly suitable land for agriculture. The study demonstrates that GIS and MCDA are invaluable tools in facilitating evidence-based decision-making for land reform and sustainable land use management practices. The SLLI is not the panacea to land identification; there is also need to appreciate the contested nature of land in South Africa.     

Contributions of sustainability science to the study of environmental health problems

From the ontological point of view, environmental health problems do not differ from problems of unsustainability. This leads us to think that sustainability science could contribute to resolve important questions that studies on environmental health are not resolving. A literature review was made in order to analyse the scope and limitations of studies on environmental health problems. Based on the characteristics of environmental health studies, we highlighted some examples of questions that are being ignored and analysed four contributions that sustainability science could make to solve them. These contributions come from three key components of sustainability science: (1) the unit of analysis—social–ecological systems, (2) a theory—resilience theory and, specifically, social–ecological resilience, (3) and the approaches of complex systems and transdisciplinarity. From a sustainability science perspective, four contributions could be made: environmental health problems are redefined as social–ecological systems; environmental health is assumed to be the result of adaptation processes; the environment and society are recognized as systems, not as matrices of factors; and human action acquires content and structure and, in turn, explains the behaviour of environmental health problems.     

Social-ecological resilience and the quest for sustainability as object of science

The term ‘sustainability science’ has been employed to refer to a scientific trend, movement or program aimed at studying problems related to human–nature interactions. However, since it does not have its own set of principles for knowledge building and lack of a definition of a study object, sustainability science is not a science, at least in the usual sense of the word. A study object is the conceptual delimitation of the problems tackled by a science, and therefore, its search in the context of a science of sustainability requires exploring different notions of sustainability. This article presents different perspectives on the concept of sustainability and analyzes the viability to assume them as study object of sustainability science. Such exploration demands concepts based on a processual ontology that directs the researcher toward the dynamic, historic and temporal and social-ecological character of problems of unsustainability. The concept of social-ecological resilience seems to comply with such requirements.     

Mapping and evaluating sugarcane expansion in Brazil’s savanna using MODIS and intensity analysis: a case-study from the state of Tocantins

In Brazil, the main biofuel crop is sugarcane, and with its rapid expansion, there is much debate about what land uses and land covers it is replacing, and what are the associated environmental and social impacts. Some argue sugarcane is mainly replacing cattle pasture, thus having minimal impacts on native vegetation and small-scale family farming. In contrast, others claim sugarcane is replacing cropland traditionally under soybeans, rice, beans, and corn. Thus, food security is negatively affected and small-scale family farming livelihoods and culture are threatened. This is a proof-of-concept paper illustrating methods contributing toward the resolution of such debates. First we map land use and cover change in areas undergoing sugarcane expansion using satellite data from MODIS (Moderate Resolution Imaging Spectroradiometer); second, we test the hypothesis that sugarcane is replacing traditional annual crops using intensity analysis, via a case study of land change in the municipality of Pedro Afonso, Tocantins in northern Brazil between the 2008–2013 crop years. Maps matched reference data with overall agreements between 87–91%. Intensity analysis confirmed sugarcane is replacing annual crops much more than cattle pasture and other land uses and covers, pointing to particular economic and social processes driving land change.     

Stream Discharge and Riparian Land Use Influence In-Stream Concentrations and Loads of Phosphorus from Central Plains Watersheds

Total annual nutrient loads are a function of both watershed characteristics and the magnitude of nutrient mobilizing events. We investigated linkages among land cover, discharge and total phosphorus (TP) concentrations, and loads in 25 Kansas streams. Stream monitoring locations were selected from the Kansas Department of Health and Environment stream chemistry long-term monitoring network sites at or near U.S. Geological Survey stream gauges. We linked each sample with concurrent discharge data to improve our ability to estimate TP concentrations and loads across the full range of possible flow conditions. Median TP concentration was strongly linked (R ² = 76%) to the presence of cropland in the riparian zones of the mostly perennial streams. At baseflow, discharge data did not improve prediction of TP, but at high flows discharge was strongly linked to concentration (a threshold response occurred). Our data suggest that on average 88% of the total load occurred during the 10% of the time with the greatest discharge. Modeled reductions in peak discharges, representing increased hydrologic retention, predicted greater decreases in total annual loads than reductions of ambient concentrations because high discharge and elevated phosphorus concentrations had multiplicative effects. No measure of land use provided significant predictive power for concentrations when discharge was elevated or for concentration rise rates under increasing discharge. These results suggest that reductions of baseflow concentrations of TP in streams without wastewater dischargers may be managed by reductions of cropland uses in the riparian corridor. Additional measures may be needed to manage TP annual loads, due to the large percentage of the TP load occurring during a few high-flow events each year.     

营养物质对细菌质粒pEA9∷Km在土壤中接合转移频率的影响

用成团肠杆菌(Enterobacter agglomerans) T7(pEA9∷Km)为供体菌,以E.a.339(pEA9-)为受体菌在天然土壤中进行接合实验,测定各种营养物质对重组质粒pEA9∷Km同源接合转移频率的影响.实验发现,如果在土壤中只加入生理盐水或无机盐培养基,就观察不到细菌数量的增加和质粒的转移;只有加入碳源物质后才检测到细菌数量的增加和质粒的接合转移,接合转移频率的大小位于1.2×10-4～4.4×10-4之间,与所加碳源物质的种类关系不大.图2 表1 参13     

Snapping Turtles (Chelydra serpentina) As Monitors for Mercury Contamination of Aquatic Environments

We assessed the distribution of mercury in snapping turtles(Chelydra serpentina) by analyzing front shoulder muscle,back leg muscle, tail muscle, blood, liver, and marginalcarapacial scute (shell) of 26 adult turtles from five smalllakes. Total mercury concentration in muscle ranged from 50 to500 ng g^–1 wet weight and was highly correlated among the threetissue locations. There was no relationship between musclemercury concentration and body size. Mercury concentration inblood was similar to muscle; the correlation with muscle mercuryconcentration was significant but there was some variability. Mercury concentration in shell was much higher than in muscle orblood, ranging from 500 to 3300 ng g^–1, and was highly correlatedwith muscle mercury concentration. Liver mercury concentrationwas similar to shell, but was highly variable and uncorrelatedwith any other tissue. We conclude that snapping turtlesaccumulate mercury from their environment and may be usefulmonitors of mercury contamination.     

Survey on fluoride, bromide and chloride contents in public drinking water supplies in Sicily (Italy)

Six hundred and sixty-seven water samples were collected from public drinking water supplies in Sicily and analysed for electric conductivity and for their Cl(-), Br(-) and F(-) contents. The samples were, as far as possible, collected evenly over the entire territory with an average sampling density of about one sample for every 7,600 inhabitants. The contents of Cl(-) and Br(-), ranging between 5.53 and 1,302 mg/l and between <0.025 and 4.76 mg/l respectively, correlated well with the electric conductivity, a parameter used as a proxy for water salinity. The highest values were found both along the NW and SE coasts, which we attributed to seawater contamination, and in the central part of Sicily, which we attributed to evaporitic rock dissolution. The fluoride concentrations ranged from 0.023 to 3.28 mg/l, while the highest values (only three exceeding the maximum admissible concentration of 1.5 mg/l) generally correlated either with the presence in the area of crystalline (volcanic or metamorphic) or evaporitic rocks or with contamination from hydrothermal activity. Apart from these limited cases of exceeding F(-) levels, the waters of public drinking water supplies in Sicily can be considered safe for human consumption for the analysed parameters. Some limited concern could arise from the intake of bromide-rich waters (about 3% exceeding 1 mg/l) because of the potential formation of dangerous disinfection by-products.     

The Potential Use of Synthetic Aperture Radar for Estimating Methane Ebullition From Arctic Lakes1

Abstract: Arctic lakes are significant emitters of methane (CH₄), a potent greenhouse gas, to the atmosphere; yet no rigorous quantification of the magnitude and variability of pan‐Arctic lake emissions exists. In this study, we demonstrate the potential for a new method using synthetic aperture radar (SAR) imagery to detect methane bubbles in lake ice to scale up whole‐lake measurements of CH₄ ebullition (bubbling) to regional scales. We estimated ebullition from lakes, which is often the dominant mode of lake emissions, by mapping the distribution of bubble clusters frozen in early winter ice across surfaces of seven tundra lakes and one boreal forest lake in Alaska. Applying previously measured ebullition rates associated with four distinct classes of bubble clusters found in lake ice, we estimated whole‐lake emissions from individual lakes. The percent surface area of lake ice covered with bubbles (R² = 0.68) and CH₄ ebullition rates from lakes (R² = 0.59) and were correlated with radar return values from RADARSAT‐1 Standard Beam mode 3 for the tundra lakes, suggesting that with appropriate scaling and consideration for variability in lake‐ice conditions, this technique has the potential to be used for estimating broader‐scale regional and pan‐Arctic lake methane emissions.