Variation Features of Soil Physical Property of Different Forest Land Types in Southern Slope of Qilian Mountain

In chilliness area, the temperature drop of oil in buried pipeline is affected by soil temperature field, and the thermal diffusivity is one of the main of physical property the soil, which affects the temperature drop of oil directly. This paper introduced the test principle of the thermal diffusivity of soil, and researched the influence of thermal diffusivity of soil on the soil physical property, such as soil natural temperature field, soil frozen days, depth of freezing and temperature delay, which can offer theory support for the calculation of hot oil temperature drop in buried pipeline.

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Temporal and spatial variation of NPP and its response to climatic factors in main river valleys on the southern slope of Qilian Mountains

E3S Web of Conferences ◽

10.1051/e3sconf/201913101044 ◽

2019 ◽

Vol 131 ◽

pp. 01044

Author(s):

Rong-rong Yang ◽

Guang-chao Cao ◽

Sheng-kui Cao ◽

Yao Lan ◽

Zhuo Zhang ◽

...

Keyword(s):

Spatial Distribution ◽

Climatic Factors ◽

Growing Season ◽

Qilian Mountains ◽

River Valley ◽

Distribution Characteristics ◽

Southern Slope ◽

Qilian Mountain ◽

Main River ◽

River Valleys

Based on the NPP products of MODIS data, the spatial and temporal distribution characteristics of grassland NPP and its response to climatic factors in the vegetation growing season of the main river valleys in the southern slope of Qilian Mountains from 2000 to 2016 were carried out by correlation analysis and spatial interpolation. The research further provides a scientific basis for the quality evaluation of grassland ecosystems on the southern slope of Qilian Mountain and the rational use of grassland resources along the river. The results show that: (1) With the increasing distance of buffers on both sides of the river, the NPP of grassland in each year shows the characteristics of “single-peak” distribution, which is increased first and then decreased; (2) the NPP of grassland in the main river valley of the southern slope of Qilian Mountain The spatial distribution characteristics show a trend of increasing from northwest to southeast. (3) The spatial distribution of NPP and air temperature in the main river valleys of the southern slope of Qilian Mountains is gradually increasing from northwest to southeast, but the spatial distribution correlation coefficient of NPP and precipitation in the river valley grassland of vegetation growing season basically shows a trendof decreasing from northwest to southeast.

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Spatial-temporal Pattern Evolution of Ecological Land Use in Hebei Province

E3S Web of Conferences ◽

10.1051/e3sconf/201911803045 ◽

2019 ◽

Vol 118 ◽

pp. 03045

Author(s):

Qian Wang ◽

Jinlu Li ◽

Zhongya Liang

Keyword(s):

Land Use ◽

Temporal Pattern ◽

Water Area ◽

Hebei Province ◽

Forest Land ◽

High Concentration ◽

Gis Technology ◽

Related Area ◽

Evolution Characteristics ◽

Land Types

Ecological land use is an important component of ecosystem. This study presents spatial and temporal pattern evolution characteristics of ecological land for the period from 2009 to 2017, based on GIS technology and mathematical statistics. The results show that ecological land structure is stable, amount tends to decrease, average annual decrease of 21, 000 hm2. Ecological land types were mainly transformed into farmland and urban land, Internal transformed mainly between woodland and grassland. Spatial aggregation were existed, Aggregation degree: forest land > grassland > water area and wetland > desert. But high concentration areas (“HH” related area) is reduced from 11 counties to 9 counties, and low concentration areas (“LL” related areas) increased from 37 counties to 40 counties, from 2009 to 2017. According to the results, proposals for ecological land use were put forward.

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