نتایج جستجو برای: soil compaction p 0001

تعداد نتایج: 1446986  

2011
Francesca Orlando Marco Napoli Anna Dalla Marta Francesca Natali Marco Mancini Camillo Zanchi Simone Orlandini

Minimum tillage is a soil conservation practice involving a reduction in soil disturbance and topsoil compaction, which could minimize environmental impact of the tobacco cultivation system. The objectives of this study were to evaluate the development and growth responses of Nicotiana tabacum and the changes in the physical and hydrological soil properties after the application of two differen...

2013
Anusuya Rangarajan

Interest in reduced tillage methods is expanding in response to concerns for soil quality in vegetable systems. Reduced tillage (RT) refers to systems that minimize soil disturbance and maintain at least 30% residue cover. These systems can reduce soil and wind erosion, overcome compaction challenges typical of vegetable soils, conserve organic matter and improve overall soil health. In additio...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه مازندران - پژوهشکده تربیت بدنی و علوم ورزشی 1392

زمینه و هدف: پژوهش¬های همه¬گیرشناسی مقطعی فواید فعالیت بدنی را در پیشگیری از چاقی و بیماری عروق کرونر نشان می-دهد. هدف از این مطالعه بررسی ارتباط سطح فعالیت بدنی با عوامل خطرزای قلبی¬کرونری و شاخص¬های آنتروپومتریکی مردان فعال و غیر فعال بود. روش ها: میزان فعالیت بدنی 195 مرد با دامنه سنی 64-23 سال با استفاده از پرسشنامه فعالیت بدنی بک ارزیابی شد. برخی از ویژگی¬های آنتروپومتریکی و عوامل خطرزای...

2015
Herbert Borchert Christian Huber Axel Göttlein Johann Kremer

In mechanized timber harvesting, it is common practice to build brush mats from logging residues on skid trails. Protective effects of brush mats against soil compaction are documented by several studies. On the other hand, a large quantity of nutrients is concentrated on the skid trail. Fully mechanized harvesting has been criticized frequently for this reallocation of nutrients. Is there real...

2002
Jeffrey E. Herrick

ters to characterize both agricultural and rangeland A DYNAMIC CONE PENETROMETER soils, however, has been limited by concerns about (i) FOR MEASURING SOIL instrument cost, (ii) measurement repeatability, (iii) limited ranges of soil resistance that can be measured by PENETRATION RESISTANCE a single penetrometer, and (iv) difficulties in comparing Jeffrey E. Herrick* and Tim L. Jones data collec...

2002
S. S. Prihar P. R. Gajri

Yield of dryland crops grown on stored water is determined by water use from the profile which, in turn, is related to the extent of root proliferation in different layers. Plow-soles of high strength may retard root growth and adversely affect crop production. We determined the effect of initial profile water storage and soil compaction below the seed on the growth and the yield of dryland whe...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه پیام نور - دانشگاه پیام نور استان تهران - دانشکده علوم انسانی 1391

چکیده هدف کلی این تحقیق بررسی رابطه مدیریت عملکرد و رضایت شغلی دبیران زبان انگلیسی زن مدارس شهر رشت و همچنین همبستگی این متغیرها با مدرک تحصیلی و سابقه خدمت آنان است. روش تحقیق توصیفی ازنوع همبستگی می باشد .جامعه آماری شامل103 نفر از دبیران زبان انگلیسی زن مدارس شهر رشت و نمونه گیری براساس فرمول کوکران است که نمونه شامل 80 نفر از دبیران که 40 نفراز ناحیه یک و 40نفر از دبیران ناحیه دو می باشن...

2008
Stephen Sebesta Pat Harris Wenting Liu

The Texas Department of Transportation (TxDOT) employs the impact hammer method of sample compaction for laboratory preparation of road base and subgrade materials for testing. Experience has shown that this method may not adequately represent the true field performance of the materials. This report describes results investigating how different lab compaction methods influence the laboratory ch...

2016
Andrzej Pownuk Pedro Barragan Olague Vladik Kreinovich

To measure stiffness of the compacted pavement, practitioners use the Compaction Meter Value (CMV); a ratio between the amplitude for the first harmonic of the compactor’s acceleration and the amplitude corresponding to the vibration frequency. Numerous experiments show that CMV is highly correlated with the pavement stiffness, but as of now, there is no convincing theoretical explanation for t...

A.R. Sepaskhah M.M. Maharlooei S.M. Nassiri

ABSTRACT- Maize production, which is ranked after wheat and barely in Fars province, Iran, needs a considerable amount of irrigation water that is not available in scarce water conditions in drought situations. Therefore, proper planting method can improve irrigation water management. The objectives of the present study were to investigate the effects of two planting methods, on-bed and in furr...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید