Nitrate as a predictor of cyanobacteria biomass in eutrophic lakes in a climate change context

Abstract Dry covers can be applied above tailings to reduce and prevent formation of acid mine drainage and leaching of contaminants. Efficiency of covers is affected by different parameters, of which temperature change under climate change context is one. Here, a laboratory column leaching experiment was performed under four temperatures, 5, 10, 14, and 18 °C on unoxidized tailings from Ballangen, Norway. 600 mL of water was added to each column every second week and leachate collected and analyzed for pH, salinity, alkalinity, concentrations of sulfate, Co, Fe, Mn, Ni, and Zn. A thin layer of digested sewage sludge was added to columns after the 16th leaching cycle. In total, 21 leaching cycles were performed. Results showed low oxidation of tailings and therefore high pH and low salinity, SO42−, Fe, Ni, and Co in the leachates at leaching temperature of 5 °C. Addition of sludge cover slowed down oxidation of underlying tailings and decreased leaching of SO42−, Fe, Mn, Co, Ni, and Zn from the tailings deposit, especially at relatively high temperature. 10 °C is a threshold temperature, below which leaching is not affected by the cover addition so much. At a leaching temperature higher than 10 °C, the sludge cover addition can reduce the leaching of elements significantly.

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Co-occurrence of extreme ozone and heat waves in two cities from Morocco

Satellite Oceanography and Meteorology ◽

10.18063/som.v3i3.733 ◽

2018 ◽

Vol 3 (3) ◽

Cited By ~ 4

Author(s):

Kenza KHOMSI 1,2 ◽

Houda NAJMI 2 ◽

Zineb SOUHAILI 1

Keyword(s):

Climate Change ◽

Surface Temperature ◽

Extreme Events ◽

Global Climate Change ◽

Large Scale ◽

Heat Waves ◽

Global Climate ◽

Meteorological Factor ◽

Two Cities ◽

Change Context

Temperature is the first meteorological factor to be directly involved in leading ozone (O3) extreme events. Generally, upward temperatures increase the probability of having exceedance in ozone adopted thresholds. In the global climate change context more frequent and/or persistent heat waves and extreme ozone (O3) episodes are likely to occur during in coming decades and a key question is about the coincidence and co-occurrence of these extremes. In this paper, using 7 years of surface temperature and air quality observations over two cities from Morocco (Casablanca and Marrakech) and implementing a percentile thresholding approach, we show that the extremes in temperature and ozone (O3) cluster together in many cases and that the outbreak of ozone events generally match the first or second days of heat waves. This co-occurrence of extreme episodes is highly impacted by humidity and may be overlapping large-scale episodes.

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Optimizing the benefits of housing roofers in Ho Chi Minh City to adapt to the current climate change context

10.1063/5.0067857 ◽

2021 ◽

Author(s):

Lan-Huong Pham ◽

Tu-Phuoc-Nguyen Vo ◽

Thanh-Trung Tran ◽

T. M.-Hien Tran

Keyword(s):

Climate Change ◽

Ho Chi Minh City ◽

Current Climate ◽

Change Context

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Pond Becomes a Lake: Challenges Posed by Climate Change in the Trans-Himalayan Regions of Nepal

Journal of Forest and Livelihood ◽

10.3126/jfl.v16i1.22884 ◽

2018 ◽

Vol 16 (1) ◽

pp. 87-102 ◽

Cited By ~ 1

Author(s):

Jiban Mani Poudel

Keyword(s):

Climate Change ◽

Management Practices ◽

Ecological Systems ◽

Ethnographic Study ◽

The Past ◽

Temperature And Precipitation ◽

The Social ◽

Ecological Relationship ◽

Change Context ◽

Past Climate Variability

Satellite images, repeated photography, temperature and precipitation data, and other proxy scientific evidences support the claim that climate is changing rapidly in Nepal, including in the Trans-Himalayan regions of the country. Climate change in the Trans-Himalayan region of Nepal is altering the existing relations of functional socio-ecological system for generations. This ethnographic assessment of Nhāson village looks at the disturbance posed by climate change to the social and ecological relationship in reference to livestock management practices. It focuses on two thematic areas of communities’ verbalisation of issues and challenges faced by the mountain herders in the climate change context. This paper is the product of ethnographic study between the years 2012 and 2014 in Nhāson. The locals’ attachment to environment and witnesses of change is capable of telling the story on the disturbance of climate change in the social and ecological systems, contextually. The stories gathered during walking, herding, travelling, watching and observing of the places are “real stories” with insights into the past climate variability and fluctuation which is critically valuable to understand the environmental phenomena at times when scientific evidences are not sufficient. Ethnographic study can contribute in documenting the place and cultural specific stories as a powerful evidence to climate change and its impact on grounded social and ecological systems.

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Spatiotemporal Variations in Mercury Bioaccumulation at Fine and Broad Scales for Two Freshwater Sport Fishes

Water ◽

10.3390/w10111625 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1625 ◽

Cited By ~ 2

Author(s):

Shyam Thomas ◽

Stephanie Melles ◽

Satyendra Bhavsar

Keyword(s):

Climate Change ◽

Environmental Factors ◽

Northern Pike ◽

Space Time ◽

Fine Scale ◽

Spatiotemporal Variations ◽

Scale Models ◽

Change Context ◽

Mercury Bioaccumulation ◽

Broad Scale

Bioaccumulation of mercury in sport fish is a complex process that varies in space and time. Both large-scale climatic as well as fine-scale environmental factors are drivers of these space-time variations. In this study, we avail a long-running monitoring program from Ontario, Canada to better understand spatiotemporal variations in fish mercury bioaccumulation at two distinct scales. Focusing on two common large-bodied sport fishes (Walleye and Northern Pike), the data were analyzed at fine- and broad-scales, where fine-scale implies variations in bioaccumulation at waterbody- and year-level and broad-scale captures variations across 3 latitudinal zones (~5° each) and eight time periods (~5-year each). A series of linear mixed-effects models (LMEMs) were employed to capture the spatial, temporal and spatiotemporal variations in mercury bioaccumulation. Fine-scale models were overall better fit than broad-scale models suggesting environmental factors operating at the waterbody-level and annual climatic conditions matter most. Moreover, for both scales, the space time interaction explained most of the variation. The random slopes from the best-fitting broad-scale model were used to define a bioaccumulation index that captures trends within a climate change context. The broad-scale trends suggests of multiple and potentially conflicting climate-driven mechanisms. Interestingly, broad-scale temporal trends showed contrasting bioaccumulation patterns—increasing in Northern Pike and decreasing in Walleye, thus suggesting species-specific ecological differences also matter. Overall, by taking a scale-specific approach, the study highlights the overwhelming influence of fine-scale variations and their interactions on mercury bioaccumulation; while at broad-scale the mercury bioaccumulation trends are summarized within a climate change context.

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