جستجوی مقالات مرتبط با کلیدواژه « ارزیابی اراضی » در نشریات گروه « آبخیزداری، بیابان، محیط زیست، مرتع »

Al land use changes pose a most serious challenge to agricultural production, resulting in the loss of fertile soil and food security. The present study was conducted to investigate the challenges associated with fertile agricultural lands in Iran as an attempt to examine and identify the different aspects of the threats agricultural lands are faced with. As a second step, the laws and regulations governing land use change in different countries and in Iran were reviewed and the general policies related to the protection of agricultural lands were examined.  The review of land use laws in Iran showed that, despite their abundance, they have suffered from poor law enforcement as a result of both social and historical reasons as well as a public negligence of and non-adherence to the laws. Evaluations of temporal changes in the growth and development of metropolises as provincial centers revealed that they had greatly expanded beyond their original limits to annex fertile agricultural lands in the suburbs to these large cities. The five-year statistics of the requests submitted for land use change in each province also revealed landlords’ increasing demands submitted for land use change motivated by more profits out of their property, which result in loss of fertile soil, decreased agricultural production, and endangered food security.

With the new concepts and goals defined under global ecosystem sustainability and the potential contributions of soil ecosystems to the sustainability of nature and natural resources, efforts have been made to redefine the role of the science of evaluation in achieving the goals thereby defined. Introducing the components of a sustainable ecosystem, the present study strives to explore the functions of soil ecosystem and to define the role of land assessment in developing a road map toward environmental sustainability. Although the science of evaluation serves as the foundation for decision and policy making processes, it has not yet been properly and systematically exploited to achieve optimally integrated resource management. Environmental assessment, no matter how it is employed, is still the missing link in decision and policy making processes as part of sustainable resource management. It, indeed, requires due consideration in all such processes as it plays a pivotal role in bridging all environmental, economic, and engineering disciplines. Land evaluation is a disciple that characterizes soil composition in terms of its quality, degradation, flexibility, safety, health, productivity, behavior, and efficiency and, in conjunction with an evaluation of soil ecosystem functions, defines the roles each of the soil characteristics plays in integrated land management.

Many of scientists, managers, and the public are interested in assessing the health of communities and ecosystems. This has resulted in increased studies of the usefulness of different indicators as a measure of stressors and contaminants. Monitoring ecosystem health requires the use of a suite of bioindicators that are biologically, methodologically, and societal, and can be used effectively over time to assess trends and provide early warning. In a successful and continuous management of lands, Bioindicators can be considered as constructive elements in assessment of soil quality. Earthworms are often referred to as bioindicators of soil quality, because they are an important part of soil ecosystem and are always present in the soils. Because of extraordinary role that earthworms have in physical, chemical and biological process in soils, and also because of the wide distribution of earthworms in soils, these creatures have been used for a lot of toxicity tests and environmental evaluations. Bioaccumulation of metals by earthworms can be used as an environmental indicator for availability of metals. In this article, the above topics including a variety of indicators and their application in land management and environmental assessments, and especially the use of earthworms as a bioindicator of soil quality in efficient monitoring will be discussed in details.

Soil degradation means lose of soil quality which usually is caused by improper use of land by human. Decline of soil quality includes lose of physical, chemical and biological properties of soil. This study aimed to identify and assess the quality of soil and land, to determine the type of land degradation and estimates their severity based on completed forms gathered field data and mapping the corresponding in GIS environment. The results showed that the soils of Arab-lu and Ordushahi regions are saline and Jabal-Kandy is also a component of saline and alkaline. Most of surface area is affected by surface erosion. Physical degradation, salinization and erosion of soil nutrients and organic matter occupied the next grades. Salinization especially on the edge of the lake as well as in some parts of the Urmia plain is visible. Recommendations for improving the quality of traditional agricultural practices into modern methods can be effective in reducing soil erosion, land degradation and leaching of nutrients and organic matter of the soil. Type of needed operations for land reclamation is available based on the type, degree and extent of degradation from related maps and can be used by experts.