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freeze thawing soil

Licong Dai, Xiaowei Guo, Yangong Du, Fawei Zhang, Xun Ke, Yingfang Cao, Yikang Li, Qian Li, Li Lin, Guangmin Cao
The Qinghai-Tibet plateau (QTP) has the world's largest area of seasonally frozen ground. Here, shallow groundwater displays behavior that is distinct from that elsewhere in the world. In the present study, we explore the seasonal and interannual variation of the shallow groundwater levels from 2012 to 2016, and attempt to quantitatively evaluate the relative influences of individual driving factors on the shallow groundwater levels based on boosted regression trees (BRT). The results show that: (1) on a seasonal scale, the groundwater levels were characterized by a double peak and double valley relationship, while on an interannual scale the groundwater levels showed a slightly downwards trend from 2012 to 2016; and (2) during the frozen period, the seasonal variation of groundwater levels was determined by mean air temperature through its effect on the soil thaw-freeze process, accounting for 53...
October 16, 2018: Ground Water
Alla Orekhova, Miloš Barták, Josef Hájek
The soil microalgae of the genus Heterococcus are found in cold environments and have been reported for the terrestrial ecosystems of several Sub-Antarctic and Antarctic Islands. This study focused on resistance of Heterococcus sp. to sub-zero temperature. Heterococcus sp. was isolated from soil samples from James Ross Island, Antarctica. Culture of Heterococcus sp. grown in liquid medium were used to study ribitol effects at sub-zero temperatures on the species resistance to rapid freezing (RF, immersion of a sample into liquid nitrogen) and consequent cultivation on agar...
October 4, 2018: Cryobiology
Brenden Ding, Fereidoun Rezanezhad, Behrad Gharedaghloo, Philippe Van Cappellen, Elodie Passeport
Bioretention cells are a popular control strategy for stormwater volume and quality, but their efficiency for water infiltration and nutrient removal under cold climate conditions has been poorly studied. In this work, soil cores were collected from an active bioretention cell containing engineered soil material amended with a phosphate sorbent medium. The cores were used in laboratory column experiments conducted to obtain a detailed characterization of the soil's bioretention performance during six consecutive freeze-thaw cycles (FTCs, from -10 to +10 °C)...
February 1, 2019: Science of the Total Environment
Bhavna Arora, Haruko M Wainwright, Dipankar Dwivedi, Lydia J S Vaughn, John B Curtis, Margaret S Torn, Baptiste Dafflon, Susan S Hubbard
There is significant spatial and temporal variability associated with greenhouse gas (GHG) fluxes in high-latitude Arctic tundra environments. The objectives of this study are to investigate temporal variability in CO2 and CH4 fluxes at Barrow, AK and to determine the factors causing this variability using a novel entropy-based classification scheme. In particular, we analyzed which geomorphic, soil, vegetation and climatic properties most explained the variability in GHG fluxes (opaque chamber measurements) during the growing season over three successive years...
February 1, 2019: Science of the Total Environment
Rachel Mackelprang, Alyssa M Grube, Regina Lamendella, Ederson da C Jesus, Alex Copeland, Chao Liang, Randall D Jackson, Charles W Rice, Stefanie Kapucija, Bayan Parsa, Susannah G Tringe, James M Tiedje, Janet K Jansson
The North American prairie covered about 3.6 million-km2 of the continent prior to European contact. Only 1-2% of the original prairie remains, but the soils that developed under these prairies are some of the most productive and fertile in the world, containing over 35% of the soil carbon in the continental United States. Cultivation may alter microbial diversity and composition, influencing the metabolism of carbon, nitrogen, and other elements. Here, we explored the structure and functional potential of the soil microbiome in paired cultivated-corn (at the time of sampling) and never-cultivated native prairie soils across a three-states transect (Wisconsin, Iowa, and Kansas) using metagenomic and 16S rRNA gene sequencing and lipid analysis...
2018: Frontiers in Microbiology
Zibo Xu, Xiaoyun Xu, Daniel C W Tsang, Xinde Cao
Biochar has been used for immobilizing heavy metals in soils due to its abundant surface functional groups and mineral components. However, as carbonaceous material, biochar in soils is susceptible to natural aging, which could alter its structural properties and ability to retain heavy metals. In this study, the impacts of pre- and post-application aging on the properties of dairy manure and sawdust biochars and the significance of different mechanisms of complexation with surface functional groups and mineral precipitation for Cd immobilization in soils were investigated...
November 2018: Environmental Pollution
Wen Zhang, Zaimin Jiang, Han Zhao, Feng Feng, Jing Cai
In the coldest part of winter, water uptake is blocked by the frozen soil and frozen stems known as 'frost drought' causing severe embolisms in woody plants. Frost drought in stems was simulated in a centrifuge by a synergy between freeze-thaw cycles and the different tensions induced by changing the rotation speed. Frost fatigue was defined as a reduction of embolism resistance after a freeze-thaw cycle and determined from 'vulnerability curves', which showed percent losses of conductivity vs tension (positive value) or xylem pressure (negative value)...
August 23, 2018: Physiologia Plantarum
Bo Peng, Jianfei Sun, Jun Liu, Weiwei Dai, Lifei Sun, Guangting Pei, Decai Gao, Chao Wang, Ping Jiang, Edith Bai
Nitrous oxide (N2 O) is an important greenhouse gas and is involved in the destruction of ozone layer. However, the underlying mechanisms of the high soil N2 O emission during the freeze-thaw (FT) period are still unclear. Here, we conducted a mesocosm study with high frequency in situ measurements to explore the responses of soil microbes to the FT cycles and their influences on soil N2 O emission. We found the high N2 O emission rate during the FT period was mainly due to the release of substrates, the maintenance of high enzyme activities at the freezing stage, and the fast recovery of microbial biomass nitrogen (MBN) and high microbial activities at the thawing stage...
January 15, 2019: Science of the Total Environment
Yinghua Juan, Nan Jiang, Lulu Tian, Xiaodong Chen, Wentao Sun, Lijun Chen
Freeze-thaw (FT) events can influence soil functions. However, the overall impact of FTs on soil bacterial communities, especially in temperate regions, remains unclear. In this study, soil samples were collected from a midtemperate region in the northeast of China, and three incubation tests were then designed with varied FT amplitudes (i.e., at a freezing temperature of -15, -9, and -3°C, respectively), frequencies of FT cycles (i.e., under one, six, and 15 FT cycles, respectively) and soil water content (SWC) values (i...
2018: BioMed Research International
Qi Qian Wu, Chuan Kuan Wang
Changes in snow-cover patterns induced by global climate change profoundly influence ecological processes in terrestrial ecosystems, including litter decomposition and soil nutrient cycling. Forest, a major terrestrial ecosystem, plays a crucial role in global biogeochemical cycling. Here, we reviewed the effects of changes in seasonal snow-cover on litter decomposition and soil nitrogen (N) cycling in forests. Global climate change would result in increasing or decreasing seasonal snow-cover depending on local conditions, with direct and indirect effects on forest litter decomposition...
July 2018: Ying Yong Sheng Tai Xue Bao, the Journal of Applied Ecology
Doerthe Tetzlaff, Thea Piovano, Pertti Ala-Aho, Aaron Smith, Sean K Carey, Philip Marsh, Philip A Wookey, Lorna E Street, Chris Soulsby
Use of isotopes to quantify the temporal dynamics of the transformation of precipitation into run-off has revealed fundamental new insights into catchment flow paths and mixing processes that influence biogeochemical transport. However, catchments underlain by permafrost have received little attention in isotope-based studies, despite their global importance in terms of rapid environmental change. These high-latitude regions offer limited access for data collection during critical periods (e.g., early phases of snowmelt)...
June 15, 2018: Hydrological Processes
Diana Araújo, Patrícia Concórdio-Reis, Ana C Marques, Chantal Sevrin, Christian Grandfils, Vítor D Alves, Elvira Fortunato, Maria A M Reis, Filomena Freitas
In this study, the flocculation properties of FucoPol, a bacterial extracellular polysaccharide, were investigated. FucoPol is a high molecular weight polymer and negatively charged due to the presence of glucuronic acid and the acyl groups succinyl and pyruvyl. High flocculation rate values (>70%) were achieved with a low bioflocculant dosage of 1 mg/L, for pH values in the range 3-5 and temperature within 15-20°C. The bioflocculant was also shown to be stable after freezing/thawing and heating up to 100°C...
July 13, 2018: Environmental Technology
Jin-Bo Li, Nan Yao, Xiu Li, Ying Zhao, A-Feng Zhang, Zhi-Long Lan, Ting Fan
In order to evaluate the effect of grazing on the mechanism for greenhouse gas emissions in the seasonal frozen soils for a typical steppe in Inner Mongolia, variations of N2 O and CO2 concentrations in different soil layers were monitored by an in situ gas collection system. Three conditions were selected:ungrazed since 1979 (UG79), ungrazed since 1999 (UG99), and continuously grazed (CG). The results showed that the profile soil N2 O and CO2 concentrations demonstrated a significant spatio-temporal distribution...
May 8, 2018: Huan Jing Ke Xue= Huanjing Kexue
Jie Yang, Zhao-Qiu Qian, Jing Wang
The impact of solidification and stabilization effects on arsenic (As) contaminated soil before and after repeated freezing and thawing or high temperature aging was investigated by tests of unconfined compressive strength (UCS), permeability, leaching concentration and fractionation. The microstructure appearance of the soil was observed using SEM. The results show that the UCS of solidified soil decreases and its permeability increases after repeated freezing and thawing or high temperature aging. In stabilized soil, the unstable species of As increase and the leaching concentration of As rises accordingly after both treatments...
November 8, 2017: Huan Jing Ke Xue= Huanjing Kexue
Minna Männistö, Jaana Vuosku, Sari Stark, Karita Saravesi, Marko Suokas, Annamari Markkola, Françoise Martz, Pasi Rautio
The northern regions are experiencing considerable changes in winter climate leading to more frequent warm periods, rain-on-snow events and reduced snow pack diminishing the insulation properties of snow cover and increasing soil frost and freeze-thaw cycles. In this study, we investigated how the lack of snow cover, formation of ice encasement and snow compaction affect the size, structure and activities of soil bacterial and fungal communities. Contrary to our hypotheses, snow manipulation treatments over one winter had limited influence on microbial community structure, bacterial or fungal copy numbers or enzyme activities...
September 1, 2018: FEMS Microbiology Ecology
Zhi Jie Li, Wan Qin Yang, Ruo Yang He, Li Yan Zhuang, Kai Jun Yang, Qun Liu, Ting Ting Li, Zhen Feng Xu
Warming-induced decrease in seasonal snow cover has a great potential to affect soil nitrogen cycle in alpine cold forest ecosystems. In this study, a wooden-shelter method was used to remove the snow accumulation. Soil nitrogen pools and mineralization rates in the snow removal and control plots were measured synchronously in three critical periods (early snow cover, deep snow cover and snow cover melting) in a subalpine spruce forest of western Sichuan, China. Seasonal snow cover kept soil from cold air temperature...
June 18, 2017: Ying Yong Sheng Tai Xue Bao, the Journal of Applied Ecology
Narayan Kumar Shrestha, Junye Wang
An ecosystem in a cold climate river basin is vulnerable to the effects of climate change affecting permafrost thaw and glacier retreat. We currently lack sufficient data and information if and how hydrological processes such as glacier retreat, snowmelt and freezing-thawing affect sediment and nutrient runoff and transport, as well as N2 O emissions in cold climate river basins. As such, we have implemented well-established, semi-empirical equations of nitrification and denitrification within the Soil and Water Assessment Tool (SWAT), which correlate the emissions with water, sediment and nutrients...
August 2018: Environmental Pollution
Nicholas C Parazoo, Almut Arneth, Thomas A M Pugh, Ben Smith, Nicholas Steiner, Kristina Luus, Roisin Commane, Josh Benmergui, Eric Stofferahn, Junjie Liu, Christian Rödenbeck, Randy Kawa, Eugenie Euskirchen, Donatella Zona, Kyle Arndt, Walt Oechel, Charles Miller
The springtime transition to regional-scale onset of photosynthesis and net ecosystem carbon uptake in boreal and tundra ecosystems are linked to the soil freeze-thaw state. We present evidence from diagnostic and inversion models constrained by satellite fluorescence and airborne CO2 from 2012 to 2014 indicating the timing and magnitude of spring carbon uptake in Alaska correlates with landscape thaw and ecoregion. Landscape thaw in boreal forests typically occurs in late April (DOY 111 ± 7) with a 29 ± 6 day lag until photosynthetic onset...
August 2018: Global Change Biology
S K Schmidt, E M S Gendron, K Vincent, A J Solon, P Sommers, Z R Schubert, L Vimercati, D L Porazinska, J L Darcy, P Sowell
Here we describe recent breakthroughs in our understanding of microbial life in dry volcanic tephra ("soil") that covers much of the surface area of the highest elevation volcanoes on Earth. Dry tephra above 6000 m.a.s.l. is perhaps the best Earth analog for the surface of Mars because these "soils" are acidic, extremely oligotrophic, exposed to a thin atmosphere, high UV fluxes, and extreme temperature fluctuations across the freezing point. The simple microbial communities found in these extreme sites have among the lowest alpha diversity of any known earthly ecosystem and contain bacteria and eukaryotes that are uniquely adapted to these extreme conditions...
August 2018: Antonie Van Leeuwenhoek
Andreas Kellerer-Pirklbauer
Solifluction is a widespread periglacial phenomenon. Little is known about present solifluction rates in Austria. The author monitored five solifluction lobes during a four-year period. Annual rates of surface velocity, vertical velocity profiles, depths of movement, and volumetric velocities were quantified using near-surface markers and painted lines. Environmental conditions were assessed using air temperature, soil texture, and ground temperature-derived parameters. The latter were used to estimate the relevance of needle-ice creep, diurnal frost creep, annual frost creep, and gelifluction...
2018: Norsk Geografisk Tidsskrift. Norwegian Journal of Geography
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