today, environmental crisis and loss of natural resources are the principle causes of the creation of environmental management systems. the optimal management of natural resources requires the assessment and classification of ecological and environmental potentials. using this method, the abilities and restrictions of resources can be recognized, and their future trends can be predicted. nebka ...

There are two main challenges in managing natural resources. One is to respond appropriately to the ecological characteristics of a given environment, preserving its integrity and functions while assuring a flow of benefits from it. This challenge is mostly about content— the what and when of managing natural resources. The other is to respond to the social characteristics of the same environme...

Discusses the implications of the economic valuation of natural resources used for tourism and relates this valuation to the concept of total economic valuation. It demonstrates how applications of the concept of total economic valuation can be supportive of the conservation of natural resources used for tourism. Techniques for valuing tourism’s natural resources are then outlined and criticall...

This paper summarizes and extends previous research that has shown evidence of a `curse of natural resourcesa } countries with great natural resource wealth tend nevertheless to grow more slowly than resource-poor countries. This result is not easily explained by other variables, or by alternative ways to measure resource abundance. This paper shows that there is little direct evidence that omi...

Renewable natural resources include those resources useful to human economies that exhibit growth, maintenance, and recovery from exploitation over an economic planning horizon. The economics of such resources has traditionally considered stocks of fish, forests, or freshwater, much like a banker would tally interest on cash deposits. From an economic point of view, the management of biomass, s...

introduction: age-related decreases in cognitive functions such as executive functions are a common phenomenon. cognitive rehabilitation with two main approaches, compensation and remediation, is used to help elderlies coping with these deficits. despite reported benefits, there are doubts on the efficacy of each of these approaches. we tried to provide effective computerized cognitive tasks as...