the rehabilitation of sandy desertified land in various dryland ecosystems by different management practices has a great potential to increase aggregate stability and improve soil quality. however, plants in general may have a different ability to sustain soil. the objective was to determine the effects of reclamation practices including haloxylon ammodendron and atriplex canescens plantation o...

abstract the saturated hydraulic conductivity (ks) is an important physical property of soil. the direct measurement of this property in soils is a difficult and time consuming process. pedotransfer functions (ptfs) provide an alternative by estimating soil parameters from more readily available soil data. the objective of this study is to determine effective factors on soil hydraulic conductiv...

background: the seeds of some medicinal plants and their compounds have long been valued for their numerous health benefits. objective:to investigate some physical and chemical properties of salvia spp. methods: some physico-chemical properties in five species of salvia seeds (consisted of s. officinalis l., s. macrosiphon l., s. hypoleuca l., s. sclarea l. and s. nemorosa l.) were measured at ...

Background: The seeds of some medicinal plants and their compounds have long been valued for their numerous health benefits. Objective:To investigate some physical and chemical properties of Salvia spp. Methods: Some physico-chemical properties in five species of Salvia seeds (consisted of S. officinalis L., S. macrosiphon L., S. hypoleuca L., S. sclarea L. and S. nemorosa L.) were measured ...

Given a set P of n points in a plane, the Geometric Minimum Diameter Spanning Tree (GMDST) of P is a tree that spans P and minimizes the Euclidian length of the longest path. The best known algorithm for this problem runs in slightly sub-cubic time. In this report, I have surveyed some algorithms and approximation schemes developed for this problem and investigated the relation between this pro...

Given a set P of points in the plane, a geometric minimum-diameter spanning tree (GMDST) of P is a spanning tree of P such that the longest path through the tree is minimized. In this paper, we present an approximation algorithm that generates a tree whose diameter is no more than (1+ ) times that of a GMDST, for any > 0. Our algorithm reduces the problem to several grid-aligned versions of the...

Let P be a set of n points in the plane. The geometric minimum-diameter spanning tree (MDST) of P is a tree that spans P and minimizes the Euclidian length of the longest path. It is known that there is always a monoor a dipolar MDST, i.e. a MDST whose longest path consists of two or three edges, respectively. The more difficult dipolar case can so far only be solved in O(n) time. This paper ha...