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Copyright of China Mining Magazine is the property of China Mining Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The present paper aimed to analyze the spatial distribution characteristics of soil physicochemical properties and soil enzyme activities in different micro-topography and their differences, and to explore the interrelationship between them, which can provide a theoretical basis for the study of alluvial fan development mechanism, ecological restoration and agricultural production in the eastern part of the Helan Mountain. [Method] The physical and chemical properties of soil and soil enzyme activity were analyzed in different micro-topography ( alluvial terrace, high diffuse beach, slotted beach and gully bed) and soil depth ( 0 - 20, 20 - 40 cm) based on field survey sampling and laboratory analysis, and the relationship between soil enzyme activity and soil physical and chemical properties was investigated by using geographic probe combined with exemplary ranking method. The relationship between soil enzyme activity and soil physicochemical properties was investigated using a geodetector combined with the canonical ranking method. [ Result] In different micro-topography, the contents of soil gravel, organic matter, total nitrogen and alkaline nitrogen showed that alluvial terrace > alluvial terrace > trough terrace > furrow bed, and the contents of fast-acting phosphorus and fast-acting potassium showed that alluvial terrace > trough terrace > furrow bed, and the contents of each element decreased with the increase of soil thickness; The differences of soil pH, total phosphorus and total potassium were not significant in different micro-topography; Soil enzyme activities in different micro-topography showed that Alkaline phosphatase and urease activities were the highest in alluvial terraces and the lowest in gully beds, while catalase and peroxidase activities were the highest in gully beds and the lowest in alluvial terraces. The activities of alkaline phosphatase, urease and peroxidase decreased with the increase of soil thickness, and the activities of peroxidase increased with the increase of soil thickness. The results of geodetecting showed that the spatial variation of soil enzyme activities in different micro-topography in the study area was the result of the joint action of various soil physicochemical properties, and different factors had different degrees of influence on soil enzyme activities. Further redundancy analysis showed that total nitrogen, alkaline nitrogen, soil gravel content and fast-acting potassium were the main indicators influencing the variation of soil enzyme activity in the alluvial fan area of the eastern Helan Mountains, with the following order of importance: Total nitrogen > alkaline nitrogen > soil gravel content > fast-acting potassium. [Conclusion] The distribution of soil enzyme activity in the alluvial fan area of the eastern Helan Mountain varies significantly between different micro-topographic soils, and the effect of each soil physical and chemical property on soil enzyme activity varies, revealing the complexity of the relationship between soil physical and chemical properties and soil enzyme activity and the diversity of factors affecting the variation of enzyme activity spatial distribution. [ABSTRACT FROM AUTHOR]

Utilizing the ice thickness data， temperature data， relative humidity data， meteorological reanalysis data and topographic elevation data obtained from the icing monitoring system of ultra-high-voltage transmission lines in China Southern Power Grid， combined with the numerical model of icing， this paper analyze the spatial and temporal distribution characteristics of a large-scale sustained icing on transmission lines in the Yunnan-Guizhou Plateau during January 24 -28， 2018.In addition， the cause of the weather is analyzed.Results show that： （1） Transmission lines in central part of Guizhou Province are the first to monitor the ice-covered， with an overall ice-covered duration length of 60 to 120 hours， and ninety percent of transmission lines have an ice-covered thickness larger than 15 millimeters， with a maximum can reach 50.74 millimeters.Transmission lines in Yunnan Province and northeastern Guangxi Province have an ice-covered duration length of 0 to 10 hours and 40 to 80 hours， respectively， with a maximum ice-covered thickness no more than 25.22 millimeters.（2） The correlation coefficient between the model simulation results and the monitoring data is above 0.9， passing the significance test with ninety-five percent confidence level （when the P value is equal to 0.049）.However， complex terrain has a significant impact on the simulation icing on transmission lines.Best simulation of transmission line ice cover for altitudes of 920 -1060 m， slopes of 7.73°~20.3°， northwest pass and northeast pass.The liquid water content of transmission lines with elevations below 920 m or slopes greater than 20.3° is overestimated.Underestimated wind speeds on transmission lines in southwest and southeast pass.The simulation results for the above two terrain backgrounds are not good.（3） The "high north and low south" potential height field and the "two troughs and one ridge" stable circulation situation in Eurasia will continuous steadily transport the cold air gathered in the East Siberian region to the south of China.In addition， the active southern branch trough and the existence of low-level southwest rapids （wind speed larger than twenty meters per second） make the abundant water vapor in the South China Sea & the Bay of Bengal continuously transported northward， providing stable water vapor conditions for this widespread ice cover event.

Copyright of Plateau Meteorology is the property of Plateau Meteorology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plant functional traits can reflect response strategies of plants to environmental changes. In this study, we used a one-way ANOVA and redundancy(RDA)to compare the differences in leaf functional characters of Dicranopteris pedata in three micro-topographies(ridge, slope and valley of the ephemeral gully)and to analyze the response and adaptation strategy of D. pedata to shallow trench micro-topography. The results were as follows:(1)The overall variation degree of leaf functional characters of D. pedata was between 0.05 and 0.47. Both leaf thickness and leaf area were showed as the order of valley > slope > ridge(P<0.05). The leaf N content at the slope was significantly higher than that at the ridge and valley. The leaf P content was significantly lower at the ridge than those at the slope and valley. There was no significant differences in specific leaf area and leaf C content among three micro-topographies.(2)D. pedata at the ridge reduced water loss to protecte itself by reducing leaf area. D. pedata at the slope increased the photosynthetic rate of leaves to promote growth by increasing the N content of leaves. D. pedata at the valley improved light capture ability to promote growth by increasing the leaf area. The above results indicate that due to the differences of soil nutrients, temperature and humidity conditions, D. pedata can achieve better adaption to the environment by adjusting nutrient content and changing leaf morphology. [ABSTRACT FROM AUTHOR]

Near-surface vegetation and micro-topography have a great impact on the surface runoff process in the mountainous areas of southwestern China. It is, therefore, necessary to clarify the combined influence on the soil and water loss of steep slopes. In this study, 10 natural runoff plots were set to reveal the effects of cypress spatial pattern and micro-topography on the surface runoff. Pearson correlation coefficient method was applied to determine the correlation between cypress spatial pattern, micro-topography, and characteristic parameters of surface runoff. A response surface method (RSM) was also utilized to analyze the measured cypress spatial pattern and micro-topography in the process of precipitation and surface runoff. The results showed that: 1) The peak flow coefficient in all runoff plots behaved short-duration rainstorm (the rainfall lasted no more than 3 h, and the maximum 1 h rainfall intensity exceeded 30 mm/h) > long-duration rainstorm (the rainfall lasted more than 3 h, and the average rainfall intensity exceeded 2.5 mm/h) > long-duration heavy rainfall (the rainfall lasted more than 3 h, and the average rainfall intensity was between 1.5-2.5 mm/h), indicating that the blocking effect of different underlays on surface runoff decreased, with the increase of rainfall intensity and concentration of precipitation. 2) Five factors were significantly correlated with the peak flow (P<0.05) in the long-duration heavy rainfall or rainstorm, including topographic relief, surface roughness, runoff path density, contagion index of cypress, and stand density of cypress. Nevertheless, there was no significant correlation with the peak flow under the condition of short-duration rainstorm. 3) In long-duration heavy rainfall or rainstorm, the response of peak flow to the composite index were that: a) There was no significant change in the peak flow, when the composite index for cypress spatial pattern (V) was below 20.5, while the composite index of micro-topography (U) was below 10.5 (Low surface roughness, high runoff path density, and low stand density of cypress). b) The peak flow was relatively promoted, as the composite index for cypress spatial pattern increased within a certain range, when U > 9.0 (High surface roughness, low runoff path density, low stand density of cypress, and uniform structure among cypress). c) The peak flow was reduced significantly with the increase of V value, when U < 7.5 and V > 18 (Low runoff path density, while high stand density of cypress). As such, when the V value was adjusted to 41 under the condition of long-duration heavy rainfall (rainstorm), an optimal combination was achieved, where the peak flow was reduced from 39.6 L/10 min (14.2 L/10 min) to 6.3 L/10 min (4.2 L/10 min), while the reduction rate reached 84% (70%). d) Once the V value exceeded the critical one (the specific critical value increased with the increase of U value), the dominant influencing factor of peak flow shifted gradually from cypress spatial pattern to micro-topography. This finding can provide promising theoretical support to accurately adjust the vegetation patterns for the prevention and control of soil erosion in the mountainous areas of southwest China. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Southern Agriculture is the property of Journal of Southern Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Influence of molding pressure on Ca(OH)2 carbonation reaction was analyzed by temperature and humidity monitoring, cube compressive strength testing, XRD and SEM test. The conclusions are as follows: calcium hydroxide test block formed under 8 MPa exhibited the most violent carbonation reaction, which is reflected in the high temperature and humidity in the carbonation kettle during the carbonation reaction process. When the molding pressure increases from 10 MPa to 14 MPa, the cube compressive strength and weight gain rate both decreased obviously. For 8 MPa molding pressure, the strongest diffraction peak of calcite exhibited sharper front and smaller half height and width, and the calcite generated by Ca(OH)2 reacting with CO2 presents ellipsoidal shape. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plant functional traits are closely tied to the performance of plants in specific microenvironments, and reflect their ability to adapt to those microenvironments. In areas with complex topography, analyzing the responses of plant functional traits to micro-topographical changes is crucial to understanding the adaptive strategies of plants in diverse environments. This paper analyzed fluctuations in soil nutrients as well as correlations between plant functional traits and changes in topography at the family and community levels in selected natural vegetation communities in the forest-steppe zone of the loess hilly and gully region in Loess Plateau of China. Significant differences in plant functional traits were primarily driven by the phylogenetic background or species composition of the community. Slope aspect exerted less impact while slope positions had no significant effect on plant traits at the community level. No significant changes in plant functional traits were observed with changes in topography at the community level. However, leaf nitrogen and root nitrogen contents of Leguminous and Compositae species differed significantly with slope positions. The root tissue density of Graminaceous species differed significantly with slope positions. Root density exhibited significant positive correlations with soil nutrient and carbon contents at the community level. Both leaf nitrogen and root nitrogen contents of Leguminous species were positively correlated with soil phosphorus content, while leaf nitrogen and root nitrogen contents of both Graminaceous and Compositae species were significantly positively related to soil nitrogen content. The results demonstrate the different responses of species of different families to changes in micro-topography and their distinctive adaptive strategies to the environment. [ABSTRACT FROM AUTHOR]

Ravine and slope are the two typical micro-topographies in the Great Xing'an Mountains. Permafrost in the two micro-topographies is extremely sensitive to global warming. To compare the differences in responses of Larix gmelinii radial growth to rapid warming in the recent 30 years, tree-ring samples were collected from northern part of Great Xing'an Mountains in Inner Mongolia and tree ring-width chronologies were developed. The results showed that the divergence between tree growth and temperature occurred in 1980 in Mo'erdaoga and in 2000 in Hanma, respectively. Since 2000, tree growth on ravine sites was greater than that on the slope stands. Chronology of two topographies reached significant level by t test in 1984-2008, the Euclidean distance was 0.937-2.742 between chronologies, and far greater than the average (0.809-1.304). The rapid warming caused a significant radial growth response in L. gmelinii to hydrothermal conditions. On the slope sites, tree growth was mainly controlled by temperature and declined gradually in recent years, while the trees growing in ravines showed an accelerating growth rate with permafrost degeneration. L. gmelinii was undergoing profound environmental pressures caused by rapid warming, and it would experience a complex growth and development process. More seriously, L. gmelinii might disappear in China with a warming climate and permafrost degeneration.