assessment of crawler tractor effects on soil surface properties

نویسندگان

a. najafi

h. sam daliri

چکیده

skidding operations can cause considerable and wide spread soil disturbance. the objective of this study was to evaluate the effects of ground skidding operations on soil compaction, moisture content, and total porosity at different levels of slope and traffic frequency. four levels of traffic intensity (3, 8, 13, and >13 passes of a crawler tractor onezhets ? 110) and three levels of slope ( 20%) were applied to assess soil disturbance. the soil samples from the depth interval 0-10 cm were collected with a soil hammer and rings. results showed that dry bulk density, moisture content and total porosity were affected considerably by slope and traffic frequency of skid trails. bulk density was drawing near to the critical value after 8 passes in the trail with the slope >20%; when the number of machine passes increased from 8 to 13 passes, the additional bulk density increment was negligible. irrespective of traffic frequency, dry bulk density increased significantly in the slope >10% compared to the slope 20% . minimum moisture content was measured as 27% on the skid trail versus 47% in the undisturbed area. a negative correlation was found between moisture content and dry bulk density. total porosity was measured as a maximum 58% to a minimum 44% on the skid trail treatments, and 65% in the undisturbed area. soil disturbance was extended dramatically on the treatments with slopes >20%, so dry bulk density on the treatments with 8 passes and slopes >20% (1.38 g cm-3) was significantly higher than on the treatment with 13 passes and slopes 10% increased soil disturbance quite dramatically.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Assessment of Crawler Tractor Effects on Soil Surface Properties

Skidding operations can cause considerable and wide spread soil disturbance. The objective of this study was to evaluate the effects of ground skidding operations on soil compaction, moisture content, and total porosity at different levels of slope and traffic frequency. Four levels of traffic intensity (3, 8, 13, and >13 passes of a Crawler Tractor Onezhets ? 110) and three levels of slope ( ...

متن کامل

Geostatistical assessment of Pb and the related soil physical and chemical properties in near-surface soil around Sepahanshahr, Isfahan

This paper presents a survey on soil Pb concentration around Sepahanshahr town located in vicinity of Isfahan. Due to the lack of regulation and environmental education and awareness, Sepahanshahr is now a rapid growing residential area suffering from the considerable consequences of poorly regulated mining activities operating in its vicinity. The aim of this study is to explore the spatial st...

متن کامل

Impact of the Repeated Tractor Passes on Some Physical Properties of Silty Loam Soil

Soil compaction caused by machinery traffic in agriculture is a well recognised problem in many parts of the world as one of the most important factor responsible for soil physical degradation and has important consequences on crop production and environment (Soane and van Ouwerkerk, 1994; Keller and Arvidsson, 2004). It is estimated to be responsible for the degradation of an area of 68 millio...

متن کامل

Soil moisture and soil-litter mixing effects on surface litter decomposition: A controlled environment assessment

Recent studies suggest the long-standing discrepancy between measured and modeled leaf litter decomposition in drylands is, in part, the result of a unique combination of abiotic drivers that include high soil surface temperature and radiant energy levels and soil-litter mixing. Temperature and radiant energy effects on litter decomposition have been widely documented. However, under field cond...

متن کامل

the effects of error correction methods on pronunciation accuracy

هدف از انجام این تحقیق مشخص کردن موثرترین متد اصلاح خطا بر روی دقت آهنگ و تاکید تلفظ کلمه در زبان انگلیسی بود. این تحقیق با پیاده کردن چهار متد ارائه اصلاح خطا در چهار گروه، سه گروه آزمایشی و یک گروه تحت کنترل، انجام شد که گروه های فوق الذکر شامل دانشجویان سطح بالای متوسط کتاب اول passages بودند. گروه اول شامل 15، دوم 14، سوم 15 و آخرین 16 دانشجو بودند. دوره مربوطه به مدت 10 هفته ادامه یافت و د...

15 صفحه اول

منابع من

با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید


عنوان ژورنال:
caspian journal of environmental sciences

ناشر: university of guilan

ISSN

دوره 11

شماره 2 2013

میزبانی شده توسط پلتفرم ابری doprax.com

copyright © 2015-2023