GM crops are well suited to high-input monoculture agricultural systems that are highly productive but largely unsustainable in their reliance on external, non-renewable inputs. Intellectual property rights granted for GM crops often close down, rather than open up further innovation potential, and stifle investment into a broader diversity of innovations allowing a greater distribution of thei...

Two-stage utility maximization theory has been widely used in the literature to estimate import demand for agricultural commodities that are often inputs. This article examines the overlooked conceptual and empirical limitations of applying two-stage utility maximization theory to model the demand for imported commodities that are inputs. A discussion is presented about how the underutilized th...

This paper proposes the construction of tables for emergy synthesis of agricultural systems using internet resources. The general model considered for these tables can be used for simple agricultural systems like chemical farming but also for complex systems as organic, agroecological and forestrycattle-agriculture systems. The construction of tables was possible due to a research on XML (exten...

Assessments of long-term relationships between changes in nutrient inputs and wetland nutrient concentrations can be complicated by fluctuations in other environmental factors as well as by problems typical of long-term monitoring data. Consequently, statistical analysis of these types of data sets requires careful consideration of environmental covariates, potential biases in the monitoring de...

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abstract-due to the important role productivity plays in future decision making and programming, the productivity indexes should have accurate quantities. in this study, auto-regressive distributed lag (ardl) and genetic algorithm (ga) methods are applied to time series of 1978-2008 to accurately measure total factor productivity (tfp) in the agricultural sector of iran. the comparison of these...