نتایج جستجو برای: use change has strong effects on ecosystem properties

تعداد نتایج: 10675689  

2015
Wei Song Xiangzheng Deng Enrico Sciubba

Since the implementation of market oriented economic reform in 1978, China has been on the track of rapid urbanization. The unprecedented urbanization in China has resulted in substantial cultivated land loss and rapid expansion of urban areas. The cultivated land loss due to urbanization not only threatens food security in China, but has also led to ecological system degradation to which close...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شیراز - دانشکده علوم پایه 1391

a simple, rapid and low-cost scanner spectroscopy method for the glucose determination by utilizing glucose oxidase and cdte/tga quantum dots as chromoionophore has been described. the detection was based on the combination of the glucose enzymatic reaction and the quenching effect of h2o2 on the cdte quantum dots (qds) photoluminescence.in this study glucose was determined by utilizing glucose...

2016
Mariska Weijerman Elizabeth A. Fulton Russell E. Brainard

Ecosystem modelling is increasingly used to explore ecosystem-level effects of changing environmental conditions and management actions. For coral reefs there has been increasing interest in recent decades in the use of ecosystem models for evaluating the effects of fishing and the efficacy of marine protected areas. However, ecosystem models that integrate physical forcings, biogeochemical and...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه لرستان - دانشکده علوم پایه 1389

abstract part one: the electrode oxidation potentials of a series of eighteen n-hydroxy compounds in aqueous solution were calculated based on a proper thermodynamic cycle. the dft method at the level of b3lyp-6-31g(d,p) was used to calculate the gas-phase free energy differences ,and the polarizable continuum model (pcm) was applied to describe the solvent and its interaction with n-hydroxy ...

Journal: :journal of the structural engineering and geotechnics 0
n shamskia assistant professor, department of civil engineering, islamic azad university, qazvin branch, qazvin, iran

there is a worldwide interest in using fibers of different types in concrete mixtures. in this regard, as the use of pet fibers has gradually increased during the last decade, this study aims to investigate the effects of pet fibers on the mechanical properties of hardened concrete and the workability of fresh concrete. to this end, different contents of pet fibers (pc= %0, %0.5, %1 and %1.5) a...

Journal: :Ecology letters 2014
Neal T Halstead Taegan A McMahon Steve A Johnson Thomas R Raffel John M Romansic Patrick W Crumrine Jason R Rohr

Ecosystems are often exposed to mixtures of chemical contaminants, but the scientific community lacks a theoretical framework to predict the effects of mixtures on biodiversity and ecosystem properties. We conducted a freshwater mesocosm experiment to examine the effects of pairwise agrochemical mixtures [fertiliser, herbicide (atrazine), insecticide (malathion) and fungicide (chlorothalonil)] ...

2018
Boris A Tinoco Vinicio E Santillán Catherine H Graham

Land use change modifies the environment at multiple spatial scales, and is a main driver of species declines and deterioration of ecosystem services. However, most of the research on the effects of land use change has focused on taxonomic diversity, while functional diversity, an important predictor of ecosystem services, is often neglected. We explored how local and landscape scale characteri...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شیراز - دانشکده علوم 1390

a novel silver (ag) nanocomposite electrode was proposed that fabricated from metal nanostructures and ionic liquids. the combined application of unique properties of nanomaterials and ionic liquids in the design of this ag nanocomposite results in electrodes with interesting advantages compared to the conventional metal disk electrode. in the first part of this thesis, the elecrocatalytic eff...

2016
Jessica E. Halofsky David L. Peterson Kerry L. Metlen M. Gwyneth Myer Andreas Bolte

Climate change will likely have significant effects on forest ecosystems worldwide. In Mediterranean regions, such as that in southwestern Oregon, USA, changes will likely be driven mainly by wildfire and drought. To minimize the negative effects of climate change, resource managers require tools and information to assess climate change vulnerabilities and to develop and implement adaptation ac...

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