Geopolymer Concrete: an Emerging Green Material for Modern Construction

Nowadays the environmental health is considered to be the most important topic for concern. The emission of CO2 and other harmful gases to the atmosphere become a serious problem and the root cause of environmental alteration. In other ways, the production of cement is reducing continuously due to the unavailability of resources and a large amount of carbon footprint. To overcome all these problems the low CO2 emitting and alumina silicate rich sources are used as binders instead of ordinary cement. The paper reviews all the recent and experimental works done by the researchers in order to study the physical and mechanical properties of Geopolymer Concrete with different mixtures of binders and additives introduced for increasing the strength and durability. The use of different industrial by-products in concrete development is encouraged and the workability, effects of temperature variation, use of admixture, fibers and effects of water- binder ratio for the Geopolymer Concrete are examined. Reviews indicate that the compressive strength of the Geopolymer Concrete with additional hooked end steel fibers are more than that of controlled Geopolymer Concrete mix.

StEMORS: A Stochastic Eco-Hydrological Model for Optimal Reservoir Sizing

Dams design and their operation cause strong environmental alteration and therefore a long-term debate is ongoing for the scale of these projects. At the same time, the concept of Environmental Flow Assessment (EFA) is a crucial element of modified ecosystems featuring large infrastructure such as dams and reservoirs for mitigating potential environmental degradation while they operate. Nowadays, integrated scientific frameworks are required to quantify the risks caused by large infrastructure. Through the use of stochastic analysis, it is possible to quantify these uncertainties, and present a solution that incorporates long-term persistence and environmental sustainability into a balanced reservoir simulation model. In this work, an attempt is made to determine a benchmark reservoir size incorporating hydrological and ecological criteria though stochastic analysis. The primary goal is to ensure the best possible conditions for the ecosystem, and then secondarily to allow a steady supply of water for other uses. Using a synthetic timeseries based on historical inputs, it is possible to determine and preserve essential statistical characteristics of a river’s streamflow, and use these to detect the optimal reservoir capacity that maximizes environmental and local water demand reliability.

Lichen Diversity and Biomonitoring: A Special Issue

Lichens are symbiotic organisms susceptible to environmental alteration due to their morphological and physiological features. For this reason, researchers and decision-makers are extensively using lichen biomonitoring for assessing the effects of various anthropogenic disturbances. The Special Issue was launched to fulfil some knowledge gaps in this field, such as the development of procedures to interpret and compare results. The SI includes three reviews that explore the application of lichen biomonitoring for detecting the effects of climate change. Three articles and one review paper examined the use at a decision level of biomonitoring of air pollution employing lichens, including the application in environmental forensic. Finally, six research articles are illustrative examples of lichen biomonitoring in poorly known habitats, providing data from the physiological to the community level of observation, and pose the basis for extending comparable approaches on a global scale.

Ragam Liken Berdasarkan Ketinggian Dataran sebagai Bioindikator Kualitas Ekosistem di Cagar Alam Rawa Danau Serang Banten

Lichen is a symbiotic organism, made up of two or more different organisms living together. Lichen biodiversity may provide an excellent system in bio-monitoring of the ecosystem health of nature reserve areas such as Rawa Danau in Banten Province, Indonesia. The study on lichen diversity was conducted on Rawa Danau based on altitude using transect based plot in three main habitats based on altitude e.g. 90 mbsl, 100-130 mbsl, 130-160 mbsl, 160-187 mbsl. A total 63 specimens were collected from these four areas which resulted in the occurrence of 19 species of lichens belonging to 17 genera and 13 families. Shannon–Winner’s diversity index from 1.494 to 2.6678. The variation in species composition was related to the environmental habitat variables and lichens demonstrated a condition of environmental alteration.

‘That this too, too solid flesh would melt…’

Physical geographers have long shown an interest in necrogeography – the spatial study of human burial practices (especially cemeteries, gravestones, and memorials) – to the extent that their study has informed investigations concerning processes of landscape change, biogeographic developments, or environmental alteration. This paper argues that such contributions can be enhanced if set within the wider study of the commemoration of death. Since the influential work of Philippe Ariès on Western attitudes towards death, scholars have been alerted to the physical implications of cultural changes in burial practices. Alternatively, others have more recently used the concept of the ‘deathscape’ to place such changes within their analyses. The paper concludes that physical geography’s contribution to the study of necrogeography could be enhanced by the adoption of such broader frameworks.

Reframing the Environment in Neoliberal India: Introduction to the Theme

Contemporary discussions on environment emphasise the use and abuse of the environment in multiple ways and means. The collective mobilisations around environmental alteration, degradation and destruction signal the crises in the material bases of life based at the intersections of caste, class and gender. This process, it is argued, has begun on an unprecedented scale since the neoliberal turn in India. There is an emerging and significant process of appropriation of land and natural resources to help the ‘growth’ story. Marginalised groups and local communities are being sidelined from access and control of resources, whether it is land, water, forest or urban commons. There are increasing instances of land appropriation for the so-called ‘environmental’ ends. However, it involves new forms of valuation, commodification and markets for different aspects of nature being built across a range of actors and alliances, such as venture capitalists, traders and consultants, ecotourism companies, green activists and consumers who seem to have common interests. Hence, the attempt would be to unravel the underlying power relations that are hidden in the present discourse of ecological sustainability.

Human Niche Construction and Population Growth in Pre-Columbian Amazonia

The use of Niche Construction Theory in archaeological research demands that we establish empirically how human-constructed niches acted as legacies that shaped the selection pressures affecting past human populations. One potential approach is to examine whether human demography changed as a result of the continued use of landscapes enduringly transformed by past societies. This paper presents proxies for Amazonian population growth during the late Holocene and discusses their significance within the broader context of landscape legacies resulting from cumulative anthropic environmental alteration during pre-Columbian times.

Microbial metabolism directly affects trace gases in (sub) polar snowpacks

Concentrations of trace gases trapped in ice are considered to develop uniquely from direct snow/atmosphere interactions at the time of contact. This assumption relies upon limited or no biological, chemical or physical transformations occurring during transition from snow to firn to ice; a process that can take decades to complete. Here, we present the first evidence of environmental alteration due to in situ microbial metabolism of trace gases (methyl halides and dimethyl sulfide) in polar snow. We collected evidence for ongoing microbial metabolism from an Arctic and an Antarctic location during different years. Methyl iodide production in the snowpack decreased significantly after exposure to enhanced UV radiation. Our results also show large variations in the production and consumption of other methyl halides, including methyl bromide and methyl chloride, used in climate interpretations. These results suggest that this long-neglected microbial activity could constitute a potential source of error in climate history interpretations, by introducing a so far unappreciated source of bias in the quantification of atmospheric-derived trace gases trapped within the polar ice caps.