نتایج جستجو برای: relative factor to plant cover and soil contains canopy cover

تعداد نتایج: 18483857  

2013
Isla H Myers-Smith David S Hik

Shrubs are the largest plant life form in tundra ecosystems; therefore, any changes in the abundance of shrubs will feedback to influence biodiversity, ecosystem function, and climate. The snow-shrub hypothesis asserts that shrub canopies trap snow and insulate soils in winter, increasing the rates of nutrient cycling to create a positive feedback to shrub expansion. However, previous work has ...

Journal: :مرتع و آبخیزداری 0
فاطمه هادیان کارشناس ارشد مرتع داری، دانشکدة منابع طبیعی، دانشگاه صنعتی اصفهان رضا جعفری استادیار دانشکدة منابع طبیعی، دانشگاه صنعتی اصفهان حسین بشری استادیار دانشکدة منابع طبیعی، دانشگاه صنعتی اصفهان سعید سلطانی دانشیار دانشکدة منابع طبیعی، دانشگاه صنعتی اصفهان

because soil moisture condition affects vegetation changes hence, monitoring of drought and vegetation changes are among valuable management tools in these ecosystems. nowadays, satellite images are used as a low-cost and fast method for vegetation study in different scales. vegetation change is assessed using vegetation spectral characteristics. this study aimed to analyze and monitor the vege...

2014
Encarna Rodríguez-García Felipe Bravo Thomas A. Spies

Seedling emergence, survival and early growth of the Mediterranean conifer P. pinaster were studied under closed canopy and open canopy (gaps) cover conditions in a Mediterranean forest of central Spain during two consecutive years (March 2008 to January 2010). Our main objective was to understand how overstorey structure, shrubs and soil properties influence recruitment in this species. Natura...

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Eco-cover is ecological mulch and its application is an eco-friendly and low-cost method to improve soil environment and prevention of unwanted plants. The aim of this study was to investigate the effects of eco-cover on unwanted plants, Vetiver grass (Chrysopogon zizanioides) growth and soil Properties. For this purpose, two series of rectangular plot (with and without eco-cover), in three rep...

Journal: :مرتع و آبخیزداری 0
سید مرتضی ابطحی استادیار، پژوهش بخش تحقیقات منابع طبیعی، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی استان اصفهان، سازمان تحقیقات، آموزش و ترویج کشاورزی

the purpose of this study was to investigate vegetation dynamics and range conditions considering the climatic conditions and soil properties in doolat gharin in the south of isfahan province of an area equal to 25 square kilometer. for this purpose, after determining vegetation types and associated species, the type of rangeland utilization, grazing season, the type of livestock and other rele...

2007
Chris B. Zou Greg A. Barron-Gafford David D. Breshears

[1] The emerging interdisciplinary approaches of ecohydrology and hydropedology are sensitive to variation in soil-surface energy inputs, which are primarily modified by topography and woody plant canopies. Yet a synthesis of the interactive effects of these two modification types is lacking. We systematically estimated near-ground surface solar radiation inputs as modified by key attributes of...

Amir Mirzaei Mossivand, Ardavan Ghorbani Ehsan Zandi Esfahan Farshad Keivan Behjou

The aim of this study was to assess the regional effects of fire on the surface cover and forage production of mountainous rangelands of Delfan County, Lorestan province, Iran. The fire took placed in June 2007 with significant effects on the vegetation characteristics in the study area. Four fire affected sites were selected for sampling and a close area without fire was considered as control....

Due to soil degradation and abundant of sediment production, the exact recognition of affecting factors on gullies erosion, and the impact of various factors on gully’s formation and development, require a more accurate study. In this regard, in the present study the length of gully, the area above headcut, headcut slope, percent of closed grain, bare soil, cover vegetation, litter, saturated e...

Journal: :محیط شناسی 0
رضا تمرتاش مربی دانشگاه علوم کشاورزی و منابع طبیعی ساری محمدرضا طاطیان استادیار دانشگاه علوم کشاورزی و منابع طبیعی ساری مائده یوسفیان دانشجوی کارشناسی ارشد مرتع داری، دانشگاه آزاد اسلامی واحد نور

carbon sequestration in soil and plant biomass is the most simple and economic way for co2 decrease that is important in environment improvement. this research was done in miankaleh region of behshahr in mazandaran for comparison of carbon sequestration in different plant types. firstly, plant types were determined and dominant species was identified in each type. number and size of plots was o...

Journal: :تولید گیاهان زراعی 0
گودرز احمدوند دانشیار گروه زراعت و اصلاح نباتات، دانشکده کشاورزی، دانشگاه بوعلی سینا همدان سمیه حاجی نیا دانشجوی دکتری فیزیولوژی گیاهان زراعی، دانشکده کشاورزی، دانشگاه بوعلی سینا

background and objectives: suitable tillage methods and planting cover crops are such factors in sustainable agricultural systems, which play an important role in the sustainability of agricultural production systems. minimum and no-tillage systems methods that leave instead of usually more than 30 percent of crop residue on the soil surface, are used to reduce soil erosion, improve soil physic...

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