نتایج جستجو برای: biomass productivity index

تعداد نتایج: 532745  

F. Hosseinzadeh Lotfi F. Rezai Balf, M. Alizadeh Afrouzi

One of the most popular approaches to measuring productivity changes is based on using Malmquist productivity indexes. In this paper we propose a method for obtaining interval Malmquist productivity index (IMPI). The classical DEA models have been before used for measuring the Malmquist productivity index. The current article extends DEA models for measuring the interval Malmquist productivity ...

2014
Kevin M. Potter Christopher W. Woodall

Biodiversity conveys numerous functional benefits to forested ecosystems, including community stability and resilience. In the context of managing forests for climate change mitigation/adaptation, maximizing and/or maintaining aboveground biomass will require understanding the interactions between tree biodiversity , site productivity, and the stocking of live trees. Species richness may not be...

Journal: :international journal of mathematical modelling and computations 0
m. fallah jelodar department of mathematics, islamic azad university, firoozkooh branch, firoozkooh, iran. m. sanei department of mathematics, islamic azad university, firoozkooh branch, firoozkooh, iran. s. mamizadeh chatghayeh

the index is excellent by the malmquist index as extended to productivity measurement. the index developed here is defined in terms of input cost rather than input quantity distance functions in supply chain. therefore, we propose productivity change is decomposed into overall efficiency and cost technical change. these decompositions provide a clearer situation of the root sources of supply ch...

Journal: :Tree physiology 1996
R E Keane K C Ryan S W Running

A mechanistic, biogeochemical succession model, FIRE-BGC, was used to investigate the role of fire on long-term landscape dynamics in northern Rocky Mountain coniferous forests of Glacier National Park, Montana, USA. FIRE-BGC is an individual-tree model-created by merging the gap-phase process-based model FIRESUM with the mechanistic ecosystem biogeochemical model FOREST-BGC-that has mixed spat...

2007
Stephanie A. Henson Andrew C. Thomas

[1] In the California Current System, strong mesoscale variability associated with eddies and meanders of the coastal jet play an important role in the biological productivity of the area. To assess the dominant timescales of variability, a wavelet analysis is applied to almost nine years (October 1997 to July 2006) of 1-km-resolution, 5-day-averaged, Seaviewing Wide Field-of-view Sensor (SeaWi...

2015
Wei Li Ji-Min Cheng Kai-Liang Yu Howard E. Epstein Liang Guo Guang-Hua Jing Jie Zhao Guo-Zhen Du Takeshi Miki

Past studies have widely documented the decrease in species diversity in response to addition of nutrients, however functional diversity is often independent from species diversity. In this study, we conducted a field experiment to examine the effect of nitrogen and phosphorus fertilization ((NH4)2 HPO4) at 0, 15, 30 and 60 g m-2 yr-1 (F0, F15, F30 and F60) after 4 years of continuous fertiliza...

2013
Geertje M. van der Heijden Stefan A. Schnitzer Jennifer S. Powers Oliver L. Phillips

Mature tropical forests sequester large quantities of atmospheric CO2, which they store as plant biomass. These forests are changing however, including an increase in liana abundance and biomass over recent decades in Neotropical forests. We ask here how this increase in lianas might impact the tropical forest carbon cycle and their capacity for carbon storage and sequestration. Lianas reduce t...

M. Fallah Jelodar M. Sanei S. Mamizadeh Chatghayeh

The index is excellent by the Malmquist index as extended to productivity measurement. The index developed here is defined in terms of input cost rather than input quantity distance functions in supply chain. Therefore, we propose productivity change is decomposed into overall efficiency and cost technical change. These decompositions provide a clearer situation of the root sources of supply ch...

M. Khoveyni, R. Eslami,

The Malmquist productivity index evaluates the productivity change of a decision making unit (DMU) between two time periods. In this current study, a method is proposed to compute the Malmquist productivity index in several time periods (from the first to the last periods) in data envelopment analysis (DEA) and then, the obtained Malmquist productivity index is compared with Malmquist produ...

M. Vaez-Ghasemi

In recent years, measuring and analyzing productivity changes is the main focus of variousresearches who study performance of organizations. All through widespread application ofMalmquist Productivity Index, different types of data should be considered thoroughly,otherwise any defective study of the related data and deciding factors may yield poor results.Practical Malmquist Productivity Index ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید