scholarly journals Response Mechanism of Sediment Organic Matter of Plateau Lakes in Cold and Arid Regions to Climate Change: a Case Study of Hulun Lake, China

2021 ◽  
Author(s):  
Wenwen Wang ◽  
Li Zhao ◽  
Wei Li ◽  
Junyi Chen ◽  
Shuhang Wang
Keyword(s):  
Climate Change ◽  
Organic Matter ◽  
Feedback Mechanism ◽  
Sediment Organic Matter ◽  
Sedimentary Evolution ◽  
Terrestrial Source ◽  
Nitrogen Ratio ◽  
Hulun Lake ◽  
Extractable Organic Matter

Abstract Lake organic matter is one of the important forms of terrestrial carbon, and its sedimentary evolution is affected by many factors such as climate and source. However, few studies have been conducted on the bidirectional feedback mechanism between the sedimentary evolution of organic matter and climate change in cold and arid lakes. Historical variations of the sediment organic matter (SOM) and source construction of Hulun Lake, a typical lake in the cold and arid region of China, were studied by multiple methods. The interactions and feedback mechanisms between the sedimentary evolution, climate change, and source construction change were also discussed. Overall, the characteristic indexes of the SOM showed obvious and uniform characteristics of periodical changes. The indexes were relatively stable before 1920, and fluctuated from 1920 to 1979. Since the 1980s, the total organic carbon, carbon stable isotope, and fluorescence intensity of the protein-like component in the water extractable organic matter in the SOM has increased, while the carbon to nitrogen ratio decreased. The absolute dominant contribution of terrestrial source to the SOM had changed, and the relative average contribution rate of autochthonous source increased from 17.6% before 1920 to 36.9% after 2000. The increase of temperature, strong evaporation concentration effect, and the source construction change are the important driving factors of the sedimentary evolution of organic matter in Hulun Lake.

scholarly journals Airborne fungi in Longyearbyen area (Svalbard, Norway) — case study

2021 ◽  
Vol 193 (5) ◽  
Author(s):  
Wojciech Pusz ◽  
Jacek Urbaniak
Keyword(s):  
Climate Change ◽  
Organic Matter ◽  
Airborne Fungi ◽  
The Arctic ◽  
Saprotrophic Fungi ◽  
Svalbard Archipelago ◽  
Arctic Environment ◽  
Dead Organic Matter ◽  
Polar Ecosystems

AbstractStudies on the presence of atmospheric fungi in both Arctic and Antarctic polar areas are rare, and many of them were carried out briefly. Currently, when climate change is a fact, polar areas may be subject to various changes and fluctuations, negatively affecting sensitive polar ecosystems. The paper presents the results of tests on presence of fungi in the air over 30 years after the last investigations at the Svalbard Archipelago. A total of fifteen taxa of fungi were isolated in area of Longyearbyen, the majority of which were saprotrophic fungi of the genus Cladosporium that are associated with dead organic matter. Therefore, the presence of this taxon may be a good bioindicator of changes occurring in the Arctic environment, indirectly indicating the melting of glaciers and exposing increasingly larger areas inhabited by microorganisms, including fungi, which increase in number in the air. Additionally, the number of tourists visiting Longyearbyen is increasing, which may significantly affect the number and type of fungi in the air.

scholarly journals Differences in the Composition, Source, and Stability of Suspended Particulate Matter and Sediment Organic Matter in Hulun Lake, China

2021 ◽  
Author(s):  
Wenwen Wang ◽  
Junyi Chen ◽  
Shuhang Wang ◽  
Wei Li
Keyword(s):  
Organic Matter ◽  
Stable Carbon Isotope ◽  
Water Environment ◽  
Three Dimensional ◽  
Organic Matters ◽  
Relative Contribution ◽  
Suspended Particulate ◽  
Fluorescence Characteristics ◽  
Hulun Lake ◽  
Extractable Organic Matter

Abstract Sediment (SOM) and suspended particulate (SPOM) organic matters are two important organic matters in water. Their occurrence, migration and transformation, and stability have important effects on the environmental behaviors of carbon, nitrogen, phosphorus, and other pollutants in a water environment. The content, composition, fluorescence characteristics, source, and stability of SOM and SPOM in Hulun Lake, a typical lake in cold and arid region of China, were compared by sequential extraction, three-dimensional fluorescence spectroscopy, parallel factor technique, carbon–nitrogen ratio, and stable carbon isotope. SOM and SPOM in north and west were higher than those in east and south. The average content of SPOM (24.70 ± 4.63 g/kg) was slightly higher than that of SOM (23.04 ± 10.27 g/kg), but the difference was not significant. Humin was the dominant component in SOM and SPOM, accounting for 73.7% and 61.2%, respectively. Humus was the main fluorescence component of water-extractable organic matter in SOM and SPOM, accounting for 79.9% and 70.4%, respectively, of the total fluorescence intensity. SOM and SPOM were derived from terrestrial sources with relative contribution rate of about 70%. SPOM was more influenced by autochthonous sources and had significantly lower humification degree and stability than SOM. Effects of climate changes on migration, transformation, stability, and bioavailability of organic matters and endogenous pollutants closely related to organic matters in lakes of cold and arid regions should be paid attention in the future.

Understanding the Outcomes of Climate Change Campaigns in the Australian Environmental Movement

2019 ◽  
Vol 3 (1) ◽  
pp. 1-9
Author(s):  
Robyn Gulliver ◽  
Kelly S. Fielding ◽  
Winnifred Louis
Keyword(s):  
Climate Change ◽  
Collective Action ◽  
Environmental Advocacy ◽  
Personal Support ◽  
Governmental Organizations ◽  
Collective Response ◽  
Non Governmental Organizations ◽  
Advocacy Network ◽  
Australian Climate

Climate change is a global problem requiring a collective response. Grassroots advocacy has been an important element in propelling this collective response, often through the mechanism of campaigns. However, it is not clear whether the climate change campaigns organized by the environmental advocacy groups are successful in achieving their goals, nor the degree to which other benefits may accrue to groups who run them. To investigate this further, we report a case study of the Australian climate change advocacy sector. Three methods were used to gather data to inform this case study: content analysis of climate change organizations’ websites, analysis of website text relating to campaign outcomes, and interviews with climate change campaigners. Findings demonstrate that climate change advocacy is diverse and achieving substantial successes such as the development of climate change-related legislation and divestment commitments from a range of organizations. The data also highlights additional benefits of campaigning such as gaining access to political power and increasing groups’ financial and volunteer resources. The successful outcomes of campaigns were influenced by the ability of groups to sustain strong personal support networks, use skills and resources available across the wider environmental advocacy network, and form consensus around shared strategic values. Communicating the successes of climate change advocacy could help mobilize collective action to address climate change. As such, this case study of the Australian climate change movement is relevant for both academics focusing on social movements and collective action and advocacy-focused practitioners, philanthropists, and non-governmental organizations.

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