Article history: Received 14 January 2011 Received in revised form 9 March 2012 Accepted 11 March 2012 Available online 28 March 2012 JEL classification: D1 J2 Q1

abstract oil export revenues have a major share in both iranian government incomes and gross domestic product (gdp). with regard to the importance of agricultural sector in economic growth, rural development and rural welfare improvement, this sector indubitably influenced by temporary and unexpected shocks in oil export. therefore we employed feder(1982) and auto-regressive distributed lag (ar...

development projects in natural water resources like rivers and lakes, specially transferring water to use in agriculture, domestic and industrial sector without considering environmental values, causes irrecoverable and irreversible damage to ecosystem and future options. if we consider the future generation and species rights, those damages and costs can be very much than we take in. the abov...

The extent of genetic diversity in food crops is important as it affects the risk of attack by pathogens. A drop in diversity increases this risk. Farmers may not take this into account when making crop choices, leading to what from a social perspective is an inadequate level of diversity. © 2003 Elsevier B.V. All rights reserved. JEL classification: Q1; Q2; C72

In this paper we consider the inventory problem with backorder such that both order and total demand quantities are triangular fuzzy numbers Q̃ = (q1, q0, q2), and R̃ = (r1, r0, r2) respectively, where q1 = q0−Δ1, q2 = q0+Δ2,r1 = r0−Δ3, r2 = r0+Δ4 such that 0 < Δ1 < q0, 0 < Δ2, 0 < Δ3 < r0, 0 < Δ4. Let s denote the maximum inventory quantity. Under conditions s ≤ q1 < q0 < q2 < r1 < r0 < r2, we f...

JEL classification: Q1 Q2 Q5 Most ecosystem services (ES) are neither priced nor marketed. Resource managers may fail to take into account degradation of unpriced services in their resource management decisions. Being able to estimate values for ES is fundamental to designing policies to induce resource users to provide (or improve) ES at levels that are acceptable to society. Conducting ecosys...

Wildlife Service to supply scientific information and methodologies on key environmental issues that impact fish and wildlife resources and their supporting ecosystems. Projects have been initiated in the following areas: coal extraction and conversion; power plants; mineral development; water resource analysts, including stream alterations and western water allocation; coastal ecosystems and O...

The Journal of Economic Literature codes classification system (JEL) published by the American Association (AEA) is de facto standard for research literature in economics. JEL used to classify articles, dissertations, books, book reviews, and working papers EconLit, a database maintained AEA. Over time, it has evolved extended with over 850 subclasses. This paper reviews history development sys...