نتایج جستجو برای: habitat diversity

تعداد نتایج: 235221  

Journal: :مرتع و آبخیزداری 0
سید حمزه حسینی کهنوج دانشجوی کارشناسی ارشد مرتع داری دانشکدة منابع طبیعی دانشگاه تربیت مدرس رضا عرفان زاده دانشیار گروه مرتع داری دانشکدة منابع طبیعی دانشگاه تربیت مدرس حسین آذرنیوند استاد گروه احیای مناطق خشک و کوهستانی، دانشکدة منابع طبیعی دانشگاه تهران

this study aimed to investigate the effect of habitat kind on soil seed bank characteristics viz. density diversity, richness and similarity between seed bank and above ground vegetation. two different habitats (grassland and forest) were selected in vaz, mazandaran province. the grassland habitat located in the upper end of the forest habitat, adjacent to each other. then in each habitat, 7 tr...

Journal: :Proceedings. Biological sciences 2006
Simon M Smart Ken Thompson Robert H Marrs Mike G Le Duc Lindsay C Maskell Leslie G Firbank

Changing land use and the spread of 'winning' native or exotic plants are expected to lead to biotic homogenization (BH), in which previously distinct plant communities become progressively more similar. In parallel, many ecosystems have recently seen increases in local species (alpha-) diversity, yet gamma-diversity has continued to decline at larger scales. Using national ecological surveilla...

2017
MICHAEL J. LACKI JOSEPH W. HUMMER

Mammal communities were studied from May through August, 1988 to 1990, at four wetland sites in Coshocton and Muskingum counties, OH. Sites represented varying degrees of disturbance from mining activity and subsequent reclamation techniques, including a wetland constructed to treat mine water drainage. Each site was composed of a series of three cattail (Typba latifolid) cells for a balanced e...

2017
Richard E. Toth

The U.5. Environmental Protection Agency's (EPA Science Advisory Board, in its report Reducing Risk: Priorities and Strategies for Environmental Protection (U.S. EPA, 1990), identified the highest priority environmental risks to the United States, based primarily on geographic extent and irreversibility of effects. Habitat modification and loss of species diversity were ranked at the highest le...

2006
Françoise Daverat Karin E. Limburg Isabel Thibault Jen-Chieh Shiao Julian J. Dodson François Caron Wann-Nian Tzeng Yoshiyuki Iizuka Håkan Wickström

Habitat use patterns of 3 species of temperate eels, Anguilla anguilla, A. japonica and A. rostrata, were investigated using otolith strontium:calcium ratio life history transects. Published and unpublished data from 6 sites (Canada, United States, Sweden, France, Taiwan and Japan) sampled across the geographical range of each eel species were compiled. Sr:Ca patterns indicated that the 3 speci...

2006
J. E. BARRETT

Data from six sites in Victoria Land (72–77oS) investigating co-variation in soil communities (microbial and invertebrate) with biogeochemical properties showthe influence of soil properties on habitat suitability varied among local landscapes as well as across climate gradients. Species richness of metazoan invertebrates (Nematoda, Tardigrada and Rotifera) was similar to previous descriptions ...

2012
Shao-ji Hu Da-ying Fu Xiao-jun Liu Tao Zhao Zhong-liang Han Jian-ping Lü Hai-long Wan Hui Ye

A field survey of the overwintering planthoppers (Hemiptera: Delphacidae) associated with the rice agroecosystems in southern Yunnan was carried out during January-February in 2010 and 2011. 22 species of planthoppers were collected and identified, with one species representing the subfamily Stenocraninae and the other 21 species in Delphacinae. Nycheuma cognatum (Muir), Peregrinus maidis (Ashm...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید