Microlysimeters of different sizes(5 cm 10 cm and 15 cm in length)were used extensively in the present study for the measurements of soil evapondion in site in an extremely arid area in southern Israel.All of the data...Microlysimeters of different sizes(5 cm 10 cm and 15 cm in length)were used extensively in the present study for the measurements of soil evapondion in site in an extremely arid area in southern Israel.All of the data obtained from the microlysimeters were used to evaluate two conventional eVaporation models developed by Black et al.and Ritchie,respectively.Our results indicated that the models could overestimate total cumulative evaporation by about 30% in the extremely arid environment.Reducing the power factor of the conventional model by a faCtor of 0.1 produced good agreement between the measured and simulated cumulative evaporation.Microlysimeter method proved to be a simple and accurate approach for the evaluation of soil evaporstion.展开更多
Lichens play an unparalleledly vital role in weathering and soil-forming processes in Antarctic region. Inthis study some related chemical components and micromorphological analyses have been carried out on thesamples...Lichens play an unparalleledly vital role in weathering and soil-forming processes in Antarctic region. Inthis study some related chemical components and micromorphological analyses have been carried out on thesamples of the weathered rocks and the lichens grown on them from Fildes Peninsula, Antarctic. The resultsindicated that the major chemical components in the bioweathering surface layer of the sampled rocks havebeen obviously altered and the weathering potential in this layer has greatly decreased by an average rangearound 4.66 percent in 4 samples. In the weathering surface layer ferruginmation of some minerals in varyingdegrees was seen by means of microscopic examination through the thin section of the weathered rocks, andits products proved to be dominated by hematite, limonite, goethite and free iron oxides Meanwhile, thestudy suggested that the dissolntion and absorption of lichens by their secretion accelerated the process ofcalcitization of minerals in the bicaweathering surface layer. Eventually, the results aIso show that differentspeciesof lichens play different roles in weathering and soilforming processes.展开更多
The yeast strain （Y18） was isolated from a soil sample collected from Fildes Peninsula, Antarctica. The strain is a psychrophilic yeast with optimum and maximum growth temperatures of 10 ℃ and 18 ℃, respectively. ...The yeast strain （Y18） was isolated from a soil sample collected from Fildes Peninsula, Antarctica. The strain is a psychrophilic yeast with optimum and maximum growth temperatures of 10 ℃ and 18 ℃, respectively. Teliospores were formed after 7 d on malt agar, when the germination of teliospores was observed. Both inositol and D-glucuronate were assimilated. Positive results of the DBB （diazonium blue B） color reaction, urease test, and starch formation were observed. The major CoQ is Qs. All results indicated that Y18 belongs to the genes of Mrakia. The 18S rDNA sequence analyses showed that Y18 is closely related to Mrakiafrigida. DNA-DNA relatedness study, and some biochemistry characteristics indicated that Y18 represents a new species for which Mrakia psychrophila sp. nov. is proposed.展开更多
Nine horizon samples of three soil profiles representative of Dystri-gelic Cambisol, Fibri-gelic Histosoland Relic Ornithosol were taken from Fildes Peninsula of King George Island, Antarctica, to quantitativelydemons...Nine horizon samples of three soil profiles representative of Dystri-gelic Cambisol, Fibri-gelic Histosoland Relic Ornithosol were taken from Fildes Peninsula of King George Island, Antarctica, to quantitativelydemonstrate the enrichment, migration and loss of the elements (Si, Al, Fe, Ca, Mg, Mn, K, Na and P) insoil horizons and their behaviours within profiles by application of the concept of the enrichment coefficientcalculated in terms of the abundance of Ti. Besides, six horizon samples of 4 other profiles randomly takenfrom the studied area were examined for calculation of the redistributing enrichment coefficient, which wasapplied for a better understanding of the element redistribution between soil and clay fraction along with soildevelopment. The results showed that the enrichment, migration and redistribution of the elements variedstrongly among the investigated soils and horizons, due to the differences of weathering degrees and moisturestatus, influences of sea bird activities, etc.展开更多
From the view of energy state of material, this paper introduces a concept of weathering potential in carrying out quantitative calculation of the relevant products at different stages of rock-weathering and primary s...From the view of energy state of material, this paper introduces a concept of weathering potential in carrying out quantitative calculation of the relevant products at different stages of rock-weathering and primary soil-forming processes, elaborates respectively on weathering degree in the bio-weathering layer of rocks and during the formation of soil material and clay, and evaluats the further tendency of weathering in the above-mentioned stages. The authors have discovered that the scales of weathering potential of the materials increase successively in the three stages, which indicates that the products in the above-mentioned three stages must have undergone stronger and stronger weathering in the primitive forming process of soil in Fildes Peninsula, Antarctic. But, because of relatively weak chemical weathering, it is reasonable that there are much more skeleton grains and little clay in primary soils in this region. Meanwhile, the authors have also verified that the weathering potential of crude rock determines to some extent decrease in the products' weathering potential in the different stages in primary soil-forming, thereby plays an important role in the genesis and development of the primary soil in the studied area.展开更多
文摘Microlysimeters of different sizes(5 cm 10 cm and 15 cm in length)were used extensively in the present study for the measurements of soil evapondion in site in an extremely arid area in southern Israel.All of the data obtained from the microlysimeters were used to evaluate two conventional eVaporation models developed by Black et al.and Ritchie,respectively.Our results indicated that the models could overestimate total cumulative evaporation by about 30% in the extremely arid environment.Reducing the power factor of the conventional model by a faCtor of 0.1 produced good agreement between the measured and simulated cumulative evaporation.Microlysimeter method proved to be a simple and accurate approach for the evaluation of soil evaporstion.
文摘Lichens play an unparalleledly vital role in weathering and soil-forming processes in Antarctic region. Inthis study some related chemical components and micromorphological analyses have been carried out on thesamples of the weathered rocks and the lichens grown on them from Fildes Peninsula, Antarctic. The resultsindicated that the major chemical components in the bioweathering surface layer of the sampled rocks havebeen obviously altered and the weathering potential in this layer has greatly decreased by an average rangearound 4.66 percent in 4 samples. In the weathering surface layer ferruginmation of some minerals in varyingdegrees was seen by means of microscopic examination through the thin section of the weathered rocks, andits products proved to be dominated by hematite, limonite, goethite and free iron oxides Meanwhile, thestudy suggested that the dissolntion and absorption of lichens by their secretion accelerated the process ofcalcitization of minerals in the bicaweathering surface layer. Eventually, the results aIso show that differentspeciesof lichens play different roles in weathering and soilforming processes.
基金Project (No. 30170001) supported by the National Natural Science Foundation of China
文摘The yeast strain （Y18） was isolated from a soil sample collected from Fildes Peninsula, Antarctica. The strain is a psychrophilic yeast with optimum and maximum growth temperatures of 10 ℃ and 18 ℃, respectively. Teliospores were formed after 7 d on malt agar, when the germination of teliospores was observed. Both inositol and D-glucuronate were assimilated. Positive results of the DBB （diazonium blue B） color reaction, urease test, and starch formation were observed. The major CoQ is Qs. All results indicated that Y18 belongs to the genes of Mrakia. The 18S rDNA sequence analyses showed that Y18 is closely related to Mrakiafrigida. DNA-DNA relatedness study, and some biochemistry characteristics indicated that Y18 represents a new species for which Mrakia psychrophila sp. nov. is proposed.
文摘Nine horizon samples of three soil profiles representative of Dystri-gelic Cambisol, Fibri-gelic Histosoland Relic Ornithosol were taken from Fildes Peninsula of King George Island, Antarctica, to quantitativelydemonstrate the enrichment, migration and loss of the elements (Si, Al, Fe, Ca, Mg, Mn, K, Na and P) insoil horizons and their behaviours within profiles by application of the concept of the enrichment coefficientcalculated in terms of the abundance of Ti. Besides, six horizon samples of 4 other profiles randomly takenfrom the studied area were examined for calculation of the redistributing enrichment coefficient, which wasapplied for a better understanding of the element redistribution between soil and clay fraction along with soildevelopment. The results showed that the enrichment, migration and redistribution of the elements variedstrongly among the investigated soils and horizons, due to the differences of weathering degrees and moisturestatus, influences of sea bird activities, etc.
文摘From the view of energy state of material, this paper introduces a concept of weathering potential in carrying out quantitative calculation of the relevant products at different stages of rock-weathering and primary soil-forming processes, elaborates respectively on weathering degree in the bio-weathering layer of rocks and during the formation of soil material and clay, and evaluats the further tendency of weathering in the above-mentioned stages. The authors have discovered that the scales of weathering potential of the materials increase successively in the three stages, which indicates that the products in the above-mentioned three stages must have undergone stronger and stronger weathering in the primitive forming process of soil in Fildes Peninsula, Antarctic. But, because of relatively weak chemical weathering, it is reasonable that there are much more skeleton grains and little clay in primary soils in this region. Meanwhile, the authors have also verified that the weathering potential of crude rock determines to some extent decrease in the products' weathering potential in the different stages in primary soil-forming, thereby plays an important role in the genesis and development of the primary soil in the studied area.
