The Impact of Animal Trampling on Free-living Nematode Abundance,Genera,and Trophic Diversity was Attenuated by Tree Canopies

• 作者: Rentao Liu Roi Meller Stanislav Pen-Mouratov Yosef Steinberger
• 来源期刊: 生命科学:英文版
• 学科: 农学
• 关键词: Grazing soil disturbances environmental factors biological indicators ecological index
• 年，卷（期）: 2019,（1）
• 页码范围: 12-33
• 页数: 22页
• 分类号: S15

摘要

Livestock grazing and trampling is an important factor in the formation and development of different terrestrial ecosystems.However,despite numerous studies on soil compaction,there is still no consensus as to which kind of effect(positive or negative)animal trampling exerts on soil nematodes.The main goal of this study was to evaluate the animal trampling effect on free-living nematode abundance and diversity,and to define the attenuating effect of the tree canopies(Cupressus sempervirens,Eucalyptus camaldulensis,and Tamarix aphylla)during wet and dry periods.The nematodes were extracted from 100 g aliquots of soil samples(brown-red sandy soils)during cold-wet(CW),warm-wet(WW),and hot-dry(HD)periods during 2013-2014,in a man-made safari-zoo habitat,using the Baermann funnel procedure.Our results revealed the impact of trampling on both free-living nematode abundance and diversity,and their soil habitat.It was found that trampling,along with seasonal fluctuation and the tree-species attenuating effect on the soil medium,resulted in the creation of the spatial-temporal heterogeneity of soil properties in the study area.In turn,variation in soil properties was reflected in soil nematode abundance and diversity,revealing tight correlation with the observed soil properties.Animal trampling had an overwhelming,mostly negative impact on soil nematode abundance,genera,and trophic diversity in the open,bare area.However,the protective effect of the tree canopies,as well as seasonal fluctuations,attenuated this negative impact.The trees had a significant attenuating effect on trampling compared with the open,bare area.However,different tree species during the wet and dry periods had a variable impact on nematode abundance,genera,and trophic diversity.During the hottest period of the year,when external adverse factors dominated the trampling effect,the ability of the trees to protect nematode communities was significantly reduced.Of all the colonizer-persister(cp)continuum of nematode functional guilds,only bacteria-feedin