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freeze thawing soil

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
Qi Yuan, Glenn Telling, Shannon L Bartelt-Hunt, Jason C Bartz
Chronic wasting disease (CWD) is an emerging prion disease in North America. Recent identification of CWD in wild cervids from Norway raises the concern of the spread of CWD in Europe. CWD infectivity can enter the environment through live animal excreta and carcasses where it can bind to soil. Well-characterized hamster prion strains and CWD field isolates in unadsorbed or soil-adsorbed forms that were either hydrated or dehydrated were subjected to repeated rounds of freezing and thawing. We found that 500 cycles of repeated freezing and thawing of hydrated samples significantly decreased the abundance of PrPSc and reduced protein misfolding cyclic amplification (PMCA) seeding activity that could be rescued by binding to soil...
April 15, 2018: Journal of Virology
Yuanyuan Hu, Lei Zhong, Yaoming Ma, Mijun Zou, Kepiao Xu, Ziyu Huang, Lu Feng
During the process of land-atmosphere interaction, one of the essential parameters is the land surface temperature (LST). The LST has high temporal variability, especially in its diurnal cycle, which cannot be acquired by polar-orbiting satellites. Therefore, it is of great practical significance to retrieve LST data using geostationary satellites. According to the data of FengYun 2C (FY-2C) satellite and the measurements from the Enhanced Observing Period (CEOP) of the Asia-Australia Monsoon Project (CAMP) on the Tibetan Plateau (CAMP/Tibet), a regression approach was utilized in this research to optimize the split window algorithm (SWA)...
January 28, 2018: Sensors
Qiang Fu, Renjie Hou, Tianxiao Li, Ruiqi Jiang, Peiru Yan, Ziao Ma, Zhaoqiang Zhou
In this study, the spatial variations of soil water and heat under bare land (BL), natural snow (NS), compacted snow (CS) and thick snow (TS) treatments were analyzed. The relationship curve between soil temperature and water content conforms to the exponential filtering model, by means of the functional form of the model, it was defined as soil water and heat relation function model. On this basis, soil water and heat function models of 10, 20, 40, 60, 100, and 140 cm were established. Finally, a spatial variation law of the relationship effect was described based on analysising of the differences between the predicted and measured results...
January 22, 2018: Scientific Reports
Weihua Wang, Tonghua Wu, Lin Zhao, Ren Li, Changwei Xie, Yongping Qiao, Huiwen Zhang, Xiaofan Zhu, Shuhua Yang, Yanhui Qin, Junming Hao
Ground ice is a distinctive feature of permafrost terrain. The vertical distribution and factors controlling the hydrochemistry of ground ice are important for studying soil moisture and salt migration during the freeze-thaw process in soil. These factors are also important components of hydrological cycles in cold regions. The hydrochemical characteristics of ground ice on the Qinghai-Tibetan Plateau (QTP) are not well known. We examined the characteristics of ground ice hydrochemistry using data from 9 soil profiles in permafrost regions of the central QTP...
June 1, 2018: Science of the Total Environment
Zuolin Liu, Brandon Dugan, Caroline A Masiello, Leila M Wahab, Helge M Gonnermann, Jeffrey A Nittrouer
Biochar may improve soil hydrology by altering soil porosity, density, hydraulic conductivity, and water-holding capacity. These properties are associated with the grain size distributions of both soil and biochar, and therefore may change as biochar weathers. Here we report how freeze-thaw (F-T) cycling impacts the grain size of pine, mesquite, miscanthus, and sewage waste biochars under two drainage conditions: undrained (all biochars) and a gravity-drained experiment (mesquite biochar only). In the undrained experiment plant biochars showed a decrease in median grain size and a change in grain-size distribution consistent with the flaking off of thin layers from the biochar surface...
2018: PloS One
Han Zhang, Zhisheng Yao, Kai Wang, Xunhua Zheng, Lei Ma, Rui Wang, Chunyan Liu, Wei Zhang, Bo Zhu, Xiangyu Tang, Zhenghua Hu, Shenghui Han
Annual nitrous oxide (N2 O) emissions from high-altitude alpine meadow grasslands have not been effectively characterized because of the scarcity of whole-year measurements. The authors performed a year-round measurement of N2 O fluxes from three conventionally grazed alpine meadows that represent the typical meadow landscape in the eastern Qinghai-Tibetan Plateau (QTP). The results showed that annual N2 O emissions averaged 0.123±0.053 (2SD, i.e., the double standard deviation indicating the 95% confidence interval) kgNha-1 yr-1 across the three meadow sites...
June 1, 2018: Science of the Total Environment
Jiusheng Ren, Changchun Song, Aixin Hou, Yanyu Song, Xiaoyan Zhu, Grace Ann Cagle
Diurnal freeze-thaw cycles (FTCs) occur in the spring and autumn in boreal wetlands as soil temperatures rise above freezing during the day and fall below freezing at night. A surge in methane emissions from these systems is frequently documented during spring FTCs, accounting for a large portion of annual emissions. In boreal wetlands, methane is produced as a result of syntrophic microbial processes, mediated by a consortium of fermenting bacteria and methanogenic archaea. Further research is needed to determine whether FTCs enhance microbial metabolism related to methane production through the cryogenic decomposition of soil organic matter...
June 1, 2018: Science of the Total Environment
Ziming Han, Mingwen Deng, Anqi Yuan, Jiahui Wang, Hao Li, Jincai Ma
Soil freeze-thaw cycles (FTCs) change soil physical, chemical, and biological properties, however information regarding their vertical variations in response to FTCs is limited. In this work, black soil (silty loam) packed soil columns were exposed to 8 FTCs, and soil properties were determined for each of vertical layer of soil columns. The results revealed that after FTCs treatment, moisture and electrical conductivity (EC) salinity tended to increase in upper soil layers. Increments of ammonium nitrogen (NH4 + -N) and nitrate nitrogen (NO3 - -N) in top layers (0-10cm) were greater than those in other layers, and increments of water soluble organic carbon (WSOC) and decrease of microbial biomass carbon (MBC) in middle layers (10-20cm) were greater than those in both ends...
June 1, 2018: Science of the Total Environment
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