TY - JOUR T1 - Depasturation Effects on Physical Characteristics, Fertility , and Tilth Index of Soil: A Case Study of Boroojen TT - مطالعه موردی تاثیر تبدیل مراتع به اراضی کشاورزی بر برخی ویژگی های فیزیکی ، حاصل خیزی ، و شاخص کشت پذیری خاک در بروجن JF - JCPP JO - JCPP VL - 6 IS - 1 UR - http://jcpp.iut.ac.ir/article-1-9-en.html Y1 - 2002 SP - 149 EP - 161 KW - Depasturation KW - Tilth index KW - Soil degradation KW - Iran N2 - Due to physiography and weak structure, the pasture soils in Boroojen are potentially degradable. Converting pastures to agricultural land accelerates the degradation processes. A study was conducted in 1999 to show the effects of almost 20 years of farming on originally pasture land on soil physical properties, fertility, and tilth index of pastures in Boroojen region in Chahar Mahal and Bakhtiari Province (central Zagrous). Soil texture, clay content, bulk density, organic matter, saturation moisture percent, cone index, plasticity index, mean weight diameter and aggregate size and distribution, nitrogen, phosphorus, and potassium were measured. After 20 years of cultivation, bulk density increased about 20% while organic matter decreased by 30%. Cone index was lower in the undisturbed pasture but nitrogen and phosphorus contents were higher compared to the disturbed pasture. The undisturbed pasture contained more larger (> 1 mm) aggregates, while the disturbed pasture had more smaller aggregates. Sustainable use of natural resources will lead to their long term workability, while negligence of conservational practices including appropriate farming management practices will result in the destruction of these resources. M3 ER -