Flow Intermittency Affects Leaf Decomposition and Benthic Consumer Communities of Alpine Streams: A Case Study along the Po River

Streams and rivers are becoming increasingly intermittent in Alpine regions due to the global climate change and related increases of local water abstractions, making it fundamental to investigate the occurrence of supraseasonal drying events and their correlated effects. We aimed to investigate leaf litter decomposition, the C:N ratio of the litter, and changes in associated macroinvertebrate communities in three reaches of the Po River: One upstream, consistently perennial, a perennial mid-reach with high hydrological variability, and an intermittent downstream reach. We placed leaf litter bags of two leaf types—chestnut and oak; both showed comparable decomposition rates, but the remaining litter mass was different and was attributed to the C:N ratio and palatability. Furthermore, (1) in perennial reaches, leaf litter decomposed faster than in the intermittent ones; (2) in intermittent reaches, the C:N ratio showed a decreasing trend in both leaf types, indicating that drying affected the nitrogen consumption, therefore the conditioning phase; (3) associated macroinvertebrate communities were richer and more stable in perennial reaches, where a higher richness and abundance of EPT taxa and shredders was observed. Our results suggest that the variations in the hydrology of mountain streams caused by global climate change could significantly impact on functional processes and biodiversity of benthic communities.

The Effects of Depth-Related Environmental Factors on Traits in Acropora cervicornis Raised in Nurseries

Populations of Acropora cervicornis, one of the most important reef-building corals in the Caribbean, have been declining due to human activities and global climate change. This has prompted the development of strategies such as coral farms, aimed at improving the long-term viability of this coral across its geographical range. This study focuses on comprehending how seawater temperature (ST), and light levels (LL) affect the survival and growth of A. cervicornis fragments collected from three reefs in Culebra, Puerto Rico. These individuals were fragmented into three pieces of the similar sizes and placed in farms at 5, 8, and 12 m depth. The fragments, ST and LL were monitored for 11 months. Results show that fragments from shallow farms exhibit significantly higher mortalities when compared to the other two depths. Yet, growth at shallow farms was nearly 24% higher than at the other two depths. Corals grew fastest during winter, when temperature and LL were lowest, regardless of the water depth. Fragment mortality and growth origin were also influenced by reef origin. We conclude that under the current conditions, shallow farms may offer a slight advantage over deep ones provided the higher growth rate at shallow farms and the high fragment survival at all depths.

Flattening the Curve: Learning the lessons of world history to mitigate societal crises

The world is experiencing myriad crises, from global climate change to a major pandemic to runaway inequality, mass impoverishment, and rising sectarian violence. Such crises are not new, but have been recurrent features of past societies. Although these periods have typically led to massive loss of life, the failure of critical institutions, and even complete societal collapse, lessons can be learned from societies that managed to avoid the more devastating and destructive outcomes. Here, we present a preliminary analysis of outcomes from periods of crisis in 50 historical societies and examine closely four cases of averted crisis in world history, highlighting common features. A key observation is that the structural-demographic cycles that give rise to societal crises typically incorporate a ‘gilded age’ during which more future-minded governance could avert future crises. To accomplish more forward-thinking public policy, capable not just of ‘flattening the curve’, but of actually breaking the cycle that produces societal crises in the first place, we argue that systematic quantitative analysis of patterns in world history is a necessary first step.

Using Digital Tools for Studying About and Addressing Climate Change

Grounded in research-based examples, this chapter provides a resource for students, teachers, and researchers to critically engage with issues of climate change through leveraging the affordances of digital tools. In particular, the authors discuss the affordances and challenges of students using digital tools to address climate change. They also review research in this field, including studies on visualizations, analyzing information, social media, digital videos, digital role-play, video games, and virtual and augmented reality. The chapter describes how digital tools offer meaning-making possibilities for students to propose solutions to climate change through engaging multimodal narratives, as well as share their voices through digital activism. Considering that global climate change is perhaps the most serious problem human beings have ever faced, this chapter offers implications for curriculum and instruction to aid educators with designing digital projects for students to understand climate change and find ways to take a stand.

Global Climate Change by Wetland Greenhouse Gas Fluxes

Wetlands (WLs) in the landscapes are important for the GHGs production, ingesting, and exchange with the atmosphere. In this chapter, the authors illustrated how the WLs influence climate change, even though it is typical for determining the climatic role of WLs in the broader perspective. The conclusions might be wary based on the radiative balance as the radiative forcing since the 1750s or climatic roles are continuously changing in the wetlands. Degradation of WLs leads to reducing their functioning, and GHG fluxes might change and alter the climatic roles of the WLs. The chapter demonstrated that WL disturbances might cause global warming for a longer duration even though the WLs are restored or managed by replacing them with the mitigation WLs. Thus, activities that cause disturbance in the WLs leading to carbon oxidation in the soils should be avoided. Regulating the climate is an ecosystem service in the WLs; during the planning of the WLs, protection, restoration, and creation, environmental management should be considered.

In Situ Observations of the Occlusion of a Clay-Sugar Compound within Calcite

The stability of soil organic matter (SOM) plays a key role in controlling global climate change as soil stores a large amount of organic carbon, compared with other ecological systems....

Revisiting Zanzibari Seaweed

Well before island nations began to consider rising ocean levels, a feature of global climate change, they have been concerned with the allocation of water resources. The purpose of this chapter is to revisit the efforts of Zanzibar's academic, as well as private and public institutions, as they promote environmentally responsible entrepreneurial projects, while advancing women's economic empowerment. Analysis will examine the history of seaweed production and consider how Zanzibar's seaweed farmers have recently responded to the dislocations associated with global climate change. This discussion will also consider to what extent Zanzibari seaweed production reflects the norms enshrined in the United Nation's Rio + 20 platform, and the language of the UN's 2030 sustainable development goals.