The growth and quality of natural seedlings are important goals of forest management in uneven-aged high stands. In this study, the recovery process of the physical and chemical properties of soil, as well as growth variables of beech seedlings on the skid trails after skidding operations in three time periods (10, 20, and 30 years) were investigated in the Hyrcanian forests of Iran.
Piping erosion is one form of water erosion that leads to significant changes in the landscape and environmental degradation. In the present study, we evaluated piping erosion modeling in the Zarandieh watershed of Markazi province in Iran based on random forest (RF), support vector machine (SVM), and Bayesian generalized linear models (Bayesian GLM) machine learning algorithms.
Soil erosion determines landforms, soil formation and distribution, soil fertility, and land degradation processes. In arid and semiarid ecosystems, soil erosion is a key process to understand, foresee, and prevent desertification. Addressing soil erosion throughout watersheds scales requires basic information to develop soil erosion control strategies and to reduce land degradation.
With the increasing concentration of population and economic activities in metropolitan regions, dwelling shortages and housing quality have become critical issues in urban management. Town plans considering social, economic, political, and cultural features of local communities have been developed with the aim of supporting housing, especially in emerging economies.
In this study, we measured and characterized the relative dielectric constant of mineral soils over the 0.3–3.0 frequency range, and compared our measurements with values of three dielectric constant simulation models (the Wang, Dobson, and Mironov models). The interrelationship between land cover and soil texture with respect to the dielectric constant was also investigated.
Arid and semi-arid regions are particularly vulnerable to global environmental change because of their fragile climatic conditions. The rapid development of land use is expected to affect aquatic ecosystems in these regions. In this study, we focused on how land use change affects the stream flow and inflow to Urmia Lake in the Mordagh Chay basin, Iran.
l'eau - source de sécurité alimentaire Journée mondiale de l'alimentation: 16 octobre 2002
Water - Source of food security. World Food Day: 16 October 2002.<p></p>Water and food security are intimately connected. Many of the over 800 million people in the world who still go hungry live in water-scarce regions.
La FAO a soumis ft titre de contribution ft la Conférence des Nations Unies sur l'eau un document de base intitulé "L'eau pour l'agriculture" (DOC. E/CONF. 70/11). Ce document passe en revue les aspects techniques, économiques et sociaux de l'eau en agriculture et propose un programme d'action pour augmenter la production alimentaire.
Increasing world population has led to product more foods and crops, while agricultural lands have been decreased. Then, it is necessary to use the maximum potential of these lands which product maximum yield without any damage. To reach this objective, land suitability evaluation is the most important way that can reach-this objective.
