A novel approach to assess livestock management effects on biodiversity of drylands

Chillo, V

Ojeda, RA

Anand, M

Reynolds, JF

2022-01-26T22:12:02Z

2022-01-26T22:12:02Z

2015-01-01

2022-01-26T22:12:00Z

In drylands livestock grazing is the main production activity, but overgrazing due to mismanagement is a major cause of biodiversity loss. Continuous grazing around water sources generates a radial gradient of grazing intensity called the piosphere. The ecological sustainability of this system is questionable and alternative management needs to be evaluated. We apply simple indicators of species response to grazing gradients, and we propose a novel methodological approach to compare community response to grazing gradients (double reciprocal analysis). We assessed degradation gradients of biodiversity under different management strategies in semiarid rangelands of the Monte desert (Argentina) by analyzing changes in vegetation, ants and small mammal richness and diversity, and variation due to seasonality. At the species level, we determined the trend in abundance of each species along the gradient, and the potential cross-taxa surrogacy. At the community level, the new methodological consists of assessing the magnitude of biodiversity degradation along different piospheres by comparing the slopes of linear functions obtained by the double reciprocal analysis. We found that most species showed a decreasing trend along the gradient under continuous grazing; while under rotational grazing fewer species showed a decreasing trend, and a neutral trend (no change in the abundance along the gradient of grazing intensity) was the most common. We found that vegetation cannot be used as a surrogacy taxon of animal response. Moreover, weak cross-taxa surrogacy was found only for animal assemblages during the wet season. The double reciprocal analysis allowed for comparison of multi-taxa response under different seasons and management types. By its application, we found that constrains in precipitation interacted with disturbance by increasing the negative effect of grazing on vegetation, but not on animal assemblages. Continuous grazing causes biodiversity loss in all situations. Rotational grazing prevents the occurrence of vegetation degradation and maintains higher levels of animal diversity, acting as an opportunity for biodiversity conservation under current scenarios of land use extensification. Our approach highlights the importance of considering multi-taxa and intrinsic variability in the analysis, and should be of value to managers concerned with biodiversity conservation.

1470-160X

1872-7034

https://hdl.handle.net/10161/24232

en

Elsevier BV

Ecological Indicators

10.1016/j.ecolind.2014.10.009

Science & Technology

Life Sciences & Biomedicine

Biodiversity Conservation

Environmental Sciences

Biodiversity & Conservation

Environmental Sciences & Ecology

Degradation

Double reciprocal analysis

Fauna

Management strategies

Multi-taxa approach

Piosphere

Seasonal variation

Semiarid rangelands

Vegetation

GRAZING GRADIENTS

MONTE DESERT

TAXONOMIC GROUPS

COMMUNITIES

VEGETATION

LANDSCAPE

DIVERSITY

PIOSPHERE

ABUNDANCE

MAMMALS

A novel approach to assess livestock management effects on biodiversity of drylands

Journal article

69

78

Duke

Nicholas School of the Environment

Environmental Sciences and Policy

Published

50