Vertical patterns and determinants of soil nutrients are critical to understand nutrient cycling in high-altitude ecosystems; however, they remain poorly understood in the alpine grassland due to lack of systematic field observations. In this study, we examined vertical distributions of soil nutrients and their influencing factors within the upper 1 m of soil, using data of 68 soil profiles surveyed in the alpine grassland of the eastern Qinghai-Tibet Plateau. Soil organic carbon (SOC) and total nitrogen (TN) stocks decreased with depth in both alpine meadow (AM) and alpine steppe (AS), but remain constant along the soil profile in alpine swamp meadow (ASM). Total phosphorus, Ca2+, and Mg2+ stocks slightly increased with depth in ASM. K+ stock decreased with depth, while Na+ stock increased slightly with depth among different vegetation types; however, SO42- and Cl- stocks remained relatively uniform throughout different depth intervals in the alpine grassland. Except for SOC and TN, soil nutrient stocks in the top 20 cm soils were significantly lower in ASM compared to those in AM and AS. Correlation analyses showed that SOC and TN stocks in the alpine grassland positively correlated with vegetation coverage, soil moisture, clay content, and silt content, while they negatively related to sand content and soil pH. However, base cation stocks revealed contrary relationships with those environmental variables compared to SOC and TN stocks. These correlations varied between vegetation types. In addition, no significant relationship was detected between topographic factors and soil nutrients. Our findings suggest that plant cycling and soil moisture primarily control vertical distributions of soil nutrients (e.g. K) in the alpine grassland and highlight that vegetation types in high-altitude permafrost regions significantly affect soil nutrients. (C) 2017 Elsevier B.V. All rights reserved.
Rockfall is one of the main geomorphological processes that affects the evolution and stability of rock-walls. At high elevations, rockfall is largely climate-driven, very probably because of the warming of rock-wall permafrost. So with the ongoing global warming that drives the degradation of permafrost, the related hazards for people and infrastructure could continue to increase. The heatwave of summer 2015, which affected Western Europe from the end of June to August, had a serious impact on the stability of high-altitude rock-walls, including those in the Mont Blanc massif. A network of observers allowed us to survey the frequency and intensity of rock-wall morphodynamics in 2015, and to verify its relationship with permafrost. These observations were compared with those of the 2003 summer heatwave, identified and quantified by remote sensing. A comparison between the two years shows a fairly similar rockfall pattern in respect of total volumes and high frequencies (about 160 rockfalls >100 m(3)) but the total volume for 2003 is higher than the 2015 one (about 300,000 m(3) and 170,000 m(3) respectively). In both cases, rockfalls were numerous but with a low magnitude and occurred in permafrost-affected areas. This suggests a sudden and remarkable deepening of the active layer during these two summers, rather than a longer-term warming of the permafrost body. (C) 2017 Elsevier B.V. All rights reserved.
本发明公开了一种基于站点的冻土指数确定方法及电子设备,涉及信息处理技术领域,包括:获取目标监测站点的历史监测数据,所述历史监测数据包括:预设时间段内所述目标监测站点采集的每日平均气温和每日平均地温以及土壤属性;将所述每日平均气温、每日平均地温及土壤属性输入到预设的冻土指数模型中,得到所述目标监测站点所对应的多个温度相关的冻土指数及多个深度相关的冻土指数,所述预设的温度模型包括多个用于计算温度相关的冻土指数的函数关系式和多个用于计算深度相关的冻土指数的函数关系式。本发明提供了一种基于站点的冻土指数确定方法,具有准确性高,运算方式简单等优点,为计算冻土指数提供一种便捷手段。
2017-12-29本发明提供了一种纯天然无伤害的洗护液,它采用椰子油、磺酸、月桂酸单甘油酯、二乙醇酰胺、烷基葡萄糖苷、片碱、氯化钠、碳酸钠、植物糖苷液、冰川活化水等原料,以中医理论为依托,主要采用天然制剂作为原料制作而成,对衣物起到很好的清洁作用,同时大大降低了洗护液对人体的伤害;多组分相互配合,能够很好的起到清洁杀菌的效果,经试验验证具有极强的去污效果。
2017-12-29本发明涉及一种人工湿地系统的净水方法,通过构建适用于低温环境的人工湿地系统,并在非冬季运行所述人工湿地系统时,关闭加热机构和曝气机构,通过所述进出水管路机构控制水流依次流经水平潜流湿地单元、垂直流湿地单元逐级进行水质净化,在冬季运行所述人工湿地系统时,将水平潜流湿地单元满水后作为冻土层,打开加热机构和曝气机构,通过进出水管路机构控制水流直接经垂直流湿地单元进行水质净化。本发明的净化方法与采用传统保温措施的人工湿地净化相比,能够显著提高湿地运行温度,具有脱氮除磷效果好、投资运行成本低、不易堵塞等优点,能够在寒冷的冬季依然保证净化效果。
2017-12-29冻胀、融沉灾害是多年冻土区对管道工程产生不良影响的主要因素,对埋地常温输油管道的安全运行造成一定的危害,因此在设计施工中要引起足够重视。通过对冻融形成的原因及冻融灾害对输油管道产生的危害进行分析,结合中俄漠大线和漠大二线两条输油管道经过多年冻土区的实践经验,以及随着管道输油温度的提升,面临高油温、并行敷设新工况对管道带来的影响,提出了行之有效的冻融防治措施。对于冻胀防治采取截流、排导、增加管道埋深以及管沟开挖换填土措施,融沉防治采取增加管道壁厚、保温敷设、热棒、混凝土桩连系梁支撑架空、木屑或生态袋护坡措施,同时对多年冻土区管道融沉情况进行实时监测,以保证输油管道安全稳定运行。
冻胀、融沉灾害是多年冻土区对管道工程产生不良影响的主要因素,对埋地常温输油管道的安全运行造成一定的危害,因此在设计施工中要引起足够重视。通过对冻融形成的原因及冻融灾害对输油管道产生的危害进行分析,结合中俄漠大线和漠大二线两条输油管道经过多年冻土区的实践经验,以及随着管道输油温度的提升,面临高油温、并行敷设新工况对管道带来的影响,提出了行之有效的冻融防治措施。对于冻胀防治采取截流、排导、增加管道埋深以及管沟开挖换填土措施,融沉防治采取增加管道壁厚、保温敷设、热棒、混凝土桩连系梁支撑架空、木屑或生态袋护坡措施,同时对多年冻土区管道融沉情况进行实时监测,以保证输油管道安全稳定运行。
冻胀、融沉灾害是多年冻土区对管道工程产生不良影响的主要因素,对埋地常温输油管道的安全运行造成一定的危害,因此在设计施工中要引起足够重视。通过对冻融形成的原因及冻融灾害对输油管道产生的危害进行分析,结合中俄漠大线和漠大二线两条输油管道经过多年冻土区的实践经验,以及随着管道输油温度的提升,面临高油温、并行敷设新工况对管道带来的影响,提出了行之有效的冻融防治措施。对于冻胀防治采取截流、排导、增加管道埋深以及管沟开挖换填土措施,融沉防治采取增加管道壁厚、保温敷设、热棒、混凝土桩连系梁支撑架空、木屑或生态袋护坡措施,同时对多年冻土区管道融沉情况进行实时监测,以保证输油管道安全稳定运行。
冻胀、融沉灾害是多年冻土区对管道工程产生不良影响的主要因素,对埋地常温输油管道的安全运行造成一定的危害,因此在设计施工中要引起足够重视。通过对冻融形成的原因及冻融灾害对输油管道产生的危害进行分析,结合中俄漠大线和漠大二线两条输油管道经过多年冻土区的实践经验,以及随着管道输油温度的提升,面临高油温、并行敷设新工况对管道带来的影响,提出了行之有效的冻融防治措施。对于冻胀防治采取截流、排导、增加管道埋深以及管沟开挖换填土措施,融沉防治采取增加管道壁厚、保温敷设、热棒、混凝土桩连系梁支撑架空、木屑或生态袋护坡措施,同时对多年冻土区管道融沉情况进行实时监测,以保证输油管道安全稳定运行。
冻胀、融沉灾害是多年冻土区对管道工程产生不良影响的主要因素,对埋地常温输油管道的安全运行造成一定的危害,因此在设计施工中要引起足够重视。通过对冻融形成的原因及冻融灾害对输油管道产生的危害进行分析,结合中俄漠大线和漠大二线两条输油管道经过多年冻土区的实践经验,以及随着管道输油温度的提升,面临高油温、并行敷设新工况对管道带来的影响,提出了行之有效的冻融防治措施。对于冻胀防治采取截流、排导、增加管道埋深以及管沟开挖换填土措施,融沉防治采取增加管道壁厚、保温敷设、热棒、混凝土桩连系梁支撑架空、木屑或生态袋护坡措施,同时对多年冻土区管道融沉情况进行实时监测,以保证输油管道安全稳定运行。