Promoting sustainability education through hands-on approaches: a tree carbon sequestration exercise in a Singapore green space.

During a university class project related to climate change mitigation strategies, we utilized a university green space as a "living laboratory" for collaborative learning exercise to estimate landscape-level carbon biomass storage. The key objective of the exercise was to foster sustainability awareness with regard to the effectiveness of tree-planting initiatives to offset carbon emissions. Collaborative learning is a process by which students work together in small groups to accomplish a common goal. As experiences are active, social and student-owned, the process leads to the development of a variety of cognitive and transferable skills that are beneficial in academia and the workplace. Through data collection/analysis, the carbon biomass exercise not only allowed students to assess critically the efficacy of a tree-planting initiative as a means to sequester carbon, but they became aware of the difficulties in performing research on complex environmental issues. The intention of the research was to give students an opportunity to practice data collection, data analysis, problem solving, teamwork, communication and scientific literacy skills, meanwhile utilizing the campus open green space to enhance the knowledge discovery process. Informal assessment and discussions with students demonstrated that the activity was successful in reaching a wide range of students with varying backgrounds and initial attitudes about climate change mitigating strategies, which was our objective. Our case study demonstrates how learning objectives can be integrated with university sustainability initiatives to improve learning and student engagement. Finally, we see green spaces as dynamic settings for learning about physical processes and issues related to environmental management and sustainability.

Pre-closure assessment of elevated arsenic and other potential environmental constraints to developing aquaculture and fisheries: The case of the Mae Moh mine and power plant, Lampang, Thailand.

Our assessment of 30 water bodies in the vicinity of the Mae Moh coal mine and power station in northern Thailand does not indicate substantial water quality management challenges to developing fisheries/aquaculture in peripheral reservoirs and streams. Negative water quality issues such as high concentrations of arsenic (2-17 µg/L) and ions including sulfate (868-2605 mg/L), sodium (217-552 mg/L), and total ammonia (<1-5 mg/L) were associated with groundwater and surface water resources on the facility, as well as the stream network draining from it. Total dissolved solids were also very high, ranging from 658 to 3610 mg/L. Six of seven ponds tested had As concentrations in the range of 5-17 µg/L. Although these levels are less than the Thai regulation for industrial effluent, they are elevated over background surface water concentrations. The highest concentration in a contaminated stream was 10.54 µg/L As, which is only slightly above the WHO (2017) regulation of 10 µg/L for drinking water. Ponds, contaminated streams, and deep subsurface water should not be used for fisheries/aquaculture without extensive remediation/treatment. Concentrations of these water parameters in peripheral streams and reservoirs were not of environmental concern. High water hardness (161-397 mg/L CaCO3 and potential ionic imbalances may be the greatest hindrances to developing sustainable fisheries and aquaculture in reservoirs in the study area. Routine monitoring of inorganic As species and other contaminants in water is needed to assess the full extent of arsenic risk at the site following closure.

Macroinvertebrate community assembly in pools created during peatland restoration.

Many degraded ecosystems are subject to restoration attempts, providing new opportunities to unravel the processes of ecological community assembly. Restoration of previously drained northern peatlands, primarily to promote peat and carbon accumulation, has created hundreds of thousands of new open water pools. We assessed the potential benefits of this wetland restoration for aquatic biodiversity, and how communities reassemble, by comparing pool ecosystems in regions of the UK Pennines on intact (never drained) versus restored (blocked drainage-ditches) peatland. We also evaluated the conceptual idea that comparing reference ecosystems in terms of their compositional similarity to null assemblages (and thus the relative importance of stochastic versus deterministic assembly) can guide evaluations of restoration success better than analyses of community composition or diversity. Community composition data highlighted some differences in the macroinvertebrate composition of restored pools compared to undisturbed peatland pools, which could be used to suggest that alternative end-points to restoration were influenced by stochastic processes. However, widely used diversity metrics indicated no differences between undisturbed and restored pools. Novel evaluations of restoration using null models confirmed the similarity of deterministic assembly processes from the national species pool across all pools. Stochastic elements were important drivers of between-pool differences at the regional-scale but the scale of these effects was also similar across most of the pools studied. The amalgamation of assembly theory into ecosystem restoration monitoring allows us to conclude with more certainty that restoration has been successful from an ecological perspective in these systems. Evaluation of these UK findings compared to those from peatlands across Europe and North America further suggests that restoring peatland pools delivers significant benefits for aquatic fauna by providing extensive new habitat that is largely equivalent to natural pools. More generally, we suggest that assembly theory could provide new benchmarks for planning and evaluating ecological restoration success.

Herbivore-induced infochemicals influence foraging behaviour in two intertidal predators.

Herbivore-induced defences appear ubiquitous across most biomes and habitats. Yet the direct correlation between induced changes in host plant chemistry and the population dynamics of the herbivore remain untested in many systems. In plant-herbivore interactions in the terrestrial environment, indirect or tritrophic interactions appear a successful way in which changes in the host plant chemistry induced by prior herbivory can impact on herbivore populations via increased success of natural enemies. This set of interactions remains untested in the marine system. Here, we present work from experiments using orthogonal contrasts of plants with different prior treatments (control, mechanical damage or herbivory) and the presence or absence of herbivores on the foraging behaviour of a crab, Carcinus maenas, and a fish, Lipophrys pholis. These experiments were carried out using a novel flow-through flume, i.e. as a choice chamber supplied by turbulent water from independent cue sources. Our results show that in the Ascophyllum nodosum (plant)-Littorina obtusata (herbivore) system infochemicals from induced plants can directly influence predator foraging behaviour. L. pholis was attracted to the presence of a feeding L. obtusata, but was also more attracted to odours from herbivore-induced tissue than odours from mechanically damaged or naïve A. nodosum. C. maenas was more attracted to odours from herbivore-induced tissue compared to naïve tissue, regardless of the presence of L. obtusata. This is the first demonstration of such behavioural consequences of herbivore-induced changes in plants for marine systems.