Knowledge of altitudinal patterns in soil C, N and P distribution is important for understanding biogeochemical processes mountainous forests, yet the influence slope aspects on stoichiometry has been largely neglected previous studies. In this paper, a total number 150 topsoil samples at four altitudes (3700, 3900, 4100, 4380 m a.s.l.) sunny shady slopes Sygera mountains Southeastern Tibet wer...

Analyze the static simulation of the dam by using the strength reduction principle, get the stress, strain and displacement distribution rule and the corresponding safety factor in the water level change and rainfall infiltration are two working conditions of the reservoir’s retaining dam body respectively, get the displacement of the slip plane when the unstable failure happens on the dam, the...

The capability of evaluating and managing rockfall related risks is largely based on numerical modelling. Nevertheless, the reliability and accuracy of rockfall models is greatly affected by the strong uncertainty and spatial variability which characterise all the relevant parameters. In particular, 3D effects related to the variability of slope geometry and micro-topography play a major role i...

A series of soil conservation measures have been carried out to reduce soil loss on the Loess Plateau of China since 1950s, and the biologic measures were implemented according to topographic factors such as slope and elevation; therefore, the changes in topographic factors of land use can indicate the effects of the biologic measures. The objectives of this study were to (i) analyze the land u...

An investigation of terrestrial bryophyte species diversity and community structure along an altitudinal gradient from 2,001 to 4,221 m a.s.l. in Gongga Mountain in Sichuan, China was carried out in June 2010. Factors which might affect bryophyte species composition and diversity, including climate, elevation, slope, depth of litter, vegetation type, soil pH and soil Eh, were examined to unders...

abstract spacing between check dams depends on the stream bed slope, effective height of check dams and slope of deposited sediments behind the check dams. the slope of deposited sediments is more important than the other two factors because of complications in the way of its occurrence and its measurement after several years of dam construction. this research presents the effective factors aff...

The use of scanning gradients can significantly reduce method-development time in reversed-phase liquid chromatography. However, there is no consensus on how they best be used. In the present work we set out to systematically investigate various factors and formulate guidelines. Scanning are used establish retention models for individual analytes. Different were compared by computing Akaike inf...

Many practical optimization problems are nonsmooth, and derivative-type methods cannot be applied. To overcome this difficulty, there are different approaches to replace the derivative of a function f : Rn → R: interval slopes, semigradients, generalized gradients, and slant derivatives are some examples. In this paper we study the relationships among these approaches for nonsmooth Lipschitz op...

Urban tunnels often easily become traffic bottlenecks. Once accidents occur, congestion, environmental pollution, personnel and property damage other problems restrict the sustainable development of tunnels. In order to reveal factors affecting incidence tunnel accidents, this paper quantitatively analyzes influence single geometric conditions control measures on in Jiaozhou Bay underwater tunn...

In April 1995, the USDA Forest Service conducted a prescribed burn along with a south-facing slope of southern Appalachian watershed, Nantahala National Forest, western NC. Fire had been excluded for over 70 years and the purpose of the burn was to create a mosaic of fire intensities to restore a degraded pine/hardwood community and to stimulate forage production and promote oak regeneration al...