In search of sustainable livestock management in the Dry Chaco: effect of different shrub-removal practices on vegetation

Author:

Guzmán L. M.,Villagra P. E.,Quiroga R. E.,Pereyra D. I.,Pelliza M. E.,Ricarte A. R.,Blanco L. J.

Abstract

Increasing shrub density hinders cattle raising in central Argentina rangelands. While roller-chopping and hand-cutting are used to remove shrubs and make land accessible for cattle grazing, studies on the effects of these practices on ecosystem composition, structure and functioning are scarce. We assessed the impact of shrub removal on (a) vegetation cover, composition, species richness and diversity and (b) green biomass and seasonal phenological dynamics. We used a randomised design with three treatments (degraded rangeland; roller-chopping and hand-cutting) with four replicates, and compared the treatments with the least disturbed woodland (conserved woodland). Cenchrus ciliaris L. was sown following removal treatments and grass cover increased significantly (45% roller-chopping and 84% hand-cutting vs 27% degraded rangeland, and 13% conserved woodland), and tree cover decreased (3% roller-chopping and 2% hand-cutting vs 16% degraded rangeland, and 23% conserved woodland). Shrub cover reached 45% under roller-chopping, similar to the degraded rangeland treatment (46% degraded rangeland, 60% conserved woodland), but in hand-cutting reached only 3% cover. Hand-cutting reduced species richness and vegetation diversity, whereas roller-chopping had no effect. Shrub-removal treatments decreased normalised difference vegetation index (NDVI; proxy of green biomass) and modified ecosystem phenology. Under both shrub treatments, the maximum, minimum and integral NDVI (area under the NDVI curve) were significantly lower than those of the degraded rangeland treatment. The results suggest that shrub-removal practices increase forage for livestock, but reduce functional diversity and compromise the return to less disturbed states (woodland), where tree populations are maintained.

Funder

Instituto Nacional de Tecologia Agropecuria

Publisher

CSIRO Publishing

Subject

Ecology,Ecology, Evolution, Behavior and Systematics

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3