نتایج جستجو برای: term exclosure increases the palatable and native species

تعداد نتایج: 21255133  

2003
Gunnar Cervin Mats Lindegarth Rosa M. Viejo Per Åberg

The effects of small-scale disturbances (80 30-cm plots) of canopy and grazers on intertidal assemblages were investigated in this 4-year experiment on sheltered rocky shores on the Swedish west coast. Canopy disturbances due to ice scouring were mimicked by removal of adult plants of the seaweed Ascophyllum nodosum (L.) Le Joli. Density of the main epilithic grazing gastropods, Littorina spp.,...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه رازی - دانشکده علوم 1390

abstract ion selective electrodes (ises) are electrochemical sensors that respond selectivity to the activity of ionic species. an ion-selective electrode is an electrochemical device that uses a thin selective membrane or film as the recognition element, and is an electrochemical half-cell equivalent to other half-cells of the zeroth (inert metal in a redox electrolyte). in common methods o...

Journal: :Environmental management 2008
Scott R Abella

Wild burros (Equus asinus), protected by the 1971 Wild Free-Roaming Horse and Burro Act on some federal lands but exotic animals many ecologists and resource mangers view as damaging to native ecosystems, represent one of the most contentious environmental management problems in American Southwest arid lands. This review synthesizes the scattered literature about burro effects on plant communit...

Journal: :Ecological applications : a publication of the Ecological Society of America 2016
Kari E Veblen Lauren M Porensky Corinna Riginos Truman P Young

The widespread replacement of wild ungulate herbivores by domestic livestock in African savannas is composed of two interrelated phenomena: (1) loss or reduction in numbers of individual wildlife species or guilds and (2) addition of livestock to the system. Each can have important implications for plant community dynamics. Yet very few studies have experimentally addressed the individual, comb...

Journal: :مرتع و آبخیزداری 0
کاظم ساعدی دکترای علوم مرتع، دانشکده مرتع و آبخیزداری، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران، و عضو هیأت علمی مرکز تحقیقات کشاورزی و منابع طبیعی کردستان عادل سپهری استاد گروه علوم مرتع، دانشکدة مرتع و آبخیزداری، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران. محمد پسرکلی استاد گروه علوم گیاهی، دانشکده کشاورزی و علوم حیاتی، دانشگاه آریزونا، توسان، آریزونا 85721، آمریکا. حسین قره داغی استادیار گروه مرتع و آبخیزداری، دانشگاه آزاد اسلامی واحد ارسنجان، ارسنجان، ایران. عادل سی و سه مرده دانشیار گروه زراعت، دانشگاه کردستان، سنندج، ایران.

this study conducted to investigate the effects of grazing in a short-term stocking system on the water-soluble carbohydrates (wsc) and nitrogen (n) reserves of permanent parts of bromus tomentellus, cephalaria kotschyi and ferula haussknekhtii in saral rangelands. a key area was selected with a permanent exclosure area and two temporary exclosure areas. root excavation was conducted at six to ...

2016
Shufeng Fan Haihao Yu Xianru Dong Ligong Wang Xiuwen Chen Dan Yu Chunhua Liu

Host-enemy interactions are vital mechanisms that explain the success or failure of invasive plants in new ranges. We surveyed the defoliation of invasive Alternanthera philoxeroides and co-occurring native plants on two islands during different seasons over three consecutive years and measured the leaf nitrogen content and the C/N ratio of each plant species. To evaluate the effects of herbivo...

Journal: :Ekologia 2021

Abstract Nowadays, the ecology and evolutionary potential of alien species are subjects several ecological studies. The goal this study was to compare feeding preference Arion ater on seedlings leaves native plant species. Seedlings three one were offered slugs individually in combination. Afterward, leaf discs from collected same source site slug’s habitat combination for slugs. When new emerg...

ایروانی, مجید , سین, جوزف, صالحی اردلی, سجاد,

Major changes in the vegetation and consequently in the ecosystem functioning of mountainous meadows has been reported in response to herbivore grazing. Nevertheless, effects of protection from herbivores on the vegetation of High-elevation meadows in Iran have not been studied so far. To assess effects of experimentally short-term exclosure treatment on production of mountainous meadows, two m...

2005

Spiders were sampled at Mpala Research Centre, Laikipia, Kenya by pitfall-trapping and sweep-netting from May 2001 to July 2002, at a Kenyan Long-term Exclosure Experiment. The aim was to establish species composition, checklist and examine spider responses to disturbances caused by cattle, megaherbivores (giraffe and elephants) and mesoherbivores (other ungulates) by looking at three levels of...

پایان نامه :دانشگاه آزاد اسلامی - دانشگاه آزاد اسلامی واحد تهران مرکزی - دانشکده ادبیات و زبانهای خارجی 1390

abstract a fundamental study of “historio-graphic metafiction” and “literary genres”, as introduced in “new historical philosophy”, and tracing them in the works of julian barnes having studied the two novels, the porcupine and arthur & george, by julian barnes, the researcher has applied linda hutcheon’s historio-graphic metafictional theories to them. the thesis is divided into five cha...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید