نتایج جستجو برای: fine soil

تعداد نتایج: 286635  

2014
Erik Grüneberg Daniel Ziche Nicole Wellbrock

The National Forest Soil Inventory (NFSI) provides the Greenhouse Gas Reporting in Germany with a quantitative assessment of organic carbon (C) stocks and changes in forest soils. Carbon stocks of the organic layer and the mineral topsoil (30 cm) were estimated on the basis of ca. 1.800 plots sampled from 1987 to 1992 and resampled from 2006 to 2008 on a nationwide grid of 8 × 8 km. Organic lay...

Journal: :مهندسی عمران و محیط زیست امیرکبیر 0
نازنین سهرابی کارشناسی ارشد، بخش راه و ساختمان و محیط زیست، دانشگاه شیراز نادر هاتف استاد، بخش راه و ساختمان و محیط زیست، دانشگاه شیراز

the pull- out strength of the reinforcement has a significant role on the function of the most reinforced soil structures. since the coarse grain soils have a better interaction with the reinforcement, they are mostly used in these structures. in most situations, we have to transfer these granular soils from the borrow area, usually far from the site of the project. this will impose a considera...

Journal: :international journal of civil engineering 0
m. khodaparast civil engineering department, university of qom, qom, iran a.m. rajabi civil engineering department, university of qom, qom, iran m. mohammadi civil engineering department, university of qom, qom, iran

the dynamic probe is an effective tool used in site investigation. it is more economic than the use of direct drilling, particularly in explorations with moderate depth. this paper presents an experimental study to investigate the capability of using dynamic probing to evaluate the shear strength and compaction percent of fine soil. a series of dynamic probe tests were carried out at 6 differen...

Journal: :تحقیقات آب و خاک ایران 0
عاطفه آزادی فر دانشگاه شهید چمران اهواز امیر سلطانی محمدی استادیار، گروه آیاری و زهکشی، دانشگاه شهید چمران اهواز هادی معاضد استاد، گروه محیط زیست، دانشگاه شهید چمران اهواز احمد فرخیان فیروزی استادیار دانشگاه شهید چمران اهواز ، گروه علوم خاک

the increasing use of nitrogen fertilizers due to high dynamics of nitrate in the soil would be a serious threat to groundwater, and therefore, to thuman health. this study is aimed to investigate the disperdivity values of nitrate in the coarse, medium and fine sandy soils in the short travel distance of 20, 40 and 80 cm in vitro using the hydrus-1d model. for this purpose, pure potassium nitr...

Soil or relative percentage of sand, silt and clay reflects some texture characteristics such as permeability, water holding capacity, CEC, and soil behavior in return to the plow and other tillage operations is very important. The study area covers an area of 1715.4 hectares, near the Aiej soil dam, East of Jooneghan city, Chaharmahal and Bakhtiari Province. For this study, 40 disturbed soil s...

This study focuses on evaluating the unconfined compressive strength (UCS) of improved fine-grained soils. A large database of unconfined compressive strength of clayey soil specimens stabilized with fly ash and blast furnace slag based geopolymer were collected and analyzed. Subsequently, using adaptive neuro fuzzy inference system (ANFIS), a model has been developed to assess the UCS of stabi...

2017
Petra Kubisch Christoph Leuschner Heinz Coners Andreas Gruber Dietrich Hertel

Low temperatures are crucial for the formation of the alpine treeline worldwide. Since soil temperature in the shade of tree canopies is lower than in open sites, it was assumed that self-shading may impair the trees' root growth performance. While experiments with tree saplings demonstrate root growth impairment at soil temperatures below 5-7°C, field studies exploring the soil temperature - r...

2014
Simeon J. Smaill Peter W. Clinton Robert B. Allen Alan C Leckie Murray R. Davis

A recent trial found that the presence of coarse soil in fine soil increased nutrient uptake by two plant species (Smaill et al., 2014). To determine if the additional nutrient uptake was derived directly from the coarse soil, the changes in coarse soil nutrient stocks were assessed. In most cases nutrient stocks increased, despite being associated with greater plant nutrient uptake. This sugge...

Journal: :مهندسی سازه 0
کاظم بدو

one and two dimensional contaminant transport by pure diffusion through single layer of fine grained soil was investigated using one and two dimensional laboratory models. these models simulates a simple hydrogeologic situation underneath a solid waste landfill comprising a fine grained soil overlying a bed rock. sodium chloride solution was sued as a contaminant source above a compacted clayey...

Journal: :Global change biology 2013
Luke M McCormack David M Eissenstat Anantha M Prasad Erica A H Smithwick

Fine root dynamics control a dominant flux of carbon from plants and into soils and mediate potential uptake and cycling of nutrients and water in terrestrial ecosystems. Understanding of these patterns is needed to accurately describe critical processes like productivity and carbon storage from ecosystem to global scales. However, limited observations of root dynamics make it difficult to defi...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید