Permission to reproduce material from other sources
SPATIAL DISTRIBUTION AND LANDSCAPE IMPACT ANALYSIS OF QUARRIES IN A
HIGHLY FRAGMENTED ECOSYSTEM
Irati Carabia-Sanz, María V. Simoy, Agustina Cortelezzi, Clara
Trofino-Falasco & Igor Berkunsky
Instituto Multidisciplinario sobre Ecosistemas y Desarrollo Sustentable,
UNICEN - CICPBA, Paraje Arroyo Seco s/n, Tandil (7000), Argentina.
Correspondence: Irati Carabia-Sanz, Instituto Multidisciplinario sobre
Ecosistemas y Desarrollo Sustentable, UNICEN - CICPBA, Paraje Arroyo
Seco s/n, Tandil (7000), Argentina.
Email:irati.casanz@gmail.com
KEY WORDS: Environmental threats; quarries; habitat destruction; native
ecosystem; land cover change; conservation.
Running title: Impact of quarries in a fragmented ecosystem
Acknowledgments: The authors are grateful for funding from the
Universidad Nacional del Centro de la Provincia de Buenos Aires
(03-PIO-65H). We want to thank Felisa for their commentaries and
support. I. Carabia-Sanz was supported by fellowships from the Comisión
de Investigaciones Científicas de la Provincia de Buenos Aires (CICPBA).
A. Cortelezzi, M.V. Simoy and I Berkunsky are Research Fellows of
Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina
CONICET.
ABSTRACT - Mining activity generates significant changes in the
ecosystems in which it takes place, affecting the atmosphere and the
surrounding aquatic and terrestrial systems, causing the destruction of
landscapes, the loss of vegetation, and altering native environments. As
it is an impact associated with increasing urbanization and population
growth, the area occupied by quarries has increased worldwide. In the
province of Buenos Aires, quarries are often abandoned without any
remediation, leading to further deterioration of the ecosystem. This
work aims to analyze quarrying activity’s spatiotemporal effect on the
Pampean grassland in the Tandilia mountains (Buenos Aires province,
Argentina). Based on Landsat 5, 7, and 8 satellite imagery, from 1996 to
the present, and using QGIS software, we identified the location and
extension of quarries, and we analyzed their evolution through time.
Quarries currently occupy an area of 6428 ha, which was originally part
of the Pampean grassland. The number of open quarries increased by
129%, from 69 in 1996 to 158 in 2022, and the area used for this
activity increased by 172%, with a greater expansion being detected in
the last ten years. These results conclude that this extractive activity
represents a major threat to the Pampean grassland with the consequent
loss of biodiversity and invasion of exotic plants capable of colonizing
areas altered by human activity.
KEYWORDS: Environmental threats; quarries; habitat destruction; native
ecosystem; land cover change; conservation.
INTRODUCTION
Quarrying is an extractive activity that causes major environmental
changes (Lameed & Ayodele, 2010; Gbedzi et al., 2022). The
environmental impacts of these changes range from pre-operational mining
activities (e.g., construction of access roads, conduits, and
installation of drains and ditches) to the mining activity itself (e.g.,
creation of openings, perforation, blasting, machinery movements; Matías
et al., 2007; Souza & Sánchez, 2018). Quarrying impacts result in
severe modifications of land cover at the local scale and affect the
whole environment, including the lithosphere (rock excavation and
geomorphic changes of the landscape), atmosphere (dust and air
pollution), hydrosphere (changes in surface water), and biosphere
(habitat destruction and biodiversity loss; Lameed & Ayodele, 2010;
Bétard, 2013). The habitat destruction and fragmentation severely reduce
the environment’s ability to provide ecosystem services, severely
impacting the native flora and fauna surrounding the quarries (Sala et
al., 2010). For example, successional processes cannot proceed in areas
affected and are stuck at the early stages of colonization, mainly due
to thin topsoil, without seed banks and rootstocks (Flavenot et al.,
2015; Lamare & Singh, 2016).
The rapid population growth coupled with industrialization has increased
tremendous pressure on natural resources resulting in the rapid
exploitation of mineral resources worldwide (Bhatnagar et al., 2014).
For example, in Lebanon, quarrying had an increase of 117% in 20 years
(Darwish et al., 2011), while Bijolia (India) showed an increase of
3570% in land use from 1971 to 1992 (Sinha et al., 2000) and Odublasi
quarry in Ghana 107,66% increase from 2007 to 2014 (Koranteng &
Adu-Asare, 2018) even when quarrying affects small areas at the regional
scale (e.g., less than 1% of French national territory; Bernaud & Le
Bloch, 1998), this extractive activity still has important consequences
on the local scale (Flavenot et al., 2014).
In the Pampa ecoregion, one of the largest grassland regions of the
world, the effect of quarries has been overlooked, and the evolution of
this activity could be following the global trend. The quarrying
activity in Pampa has more than a century of history. The number of
deposits and grassland remnants affected by the activity has increased
in the last decade (Secretaría de minería, 2020). This area is typical
granite and limestone opencast mining, where topsoil is removed to
expose the rock to be extracted (Cingolani, 2011). Opencast mining
usually requires the removal of large quantities of soil and rock. It
involves the use of machinery and explosives, which has a negative
impact on the landscape, air, and water quality (Iwanoff, 1998). The
rainwater fills these opencast mine pits dissolving the minerals such as
calcium and magnesium, which percolate downwards through fractures and
joints. This increases groundwater pollution by increasing the calcium
and magnesium, along with their carbonates, sulfates, and chlorides
affecting its hardness (Milgrom, 2008; Bhatnagar et al., 2014). All
these described impacts are intensified when the lack of control by
governmental authorities results in abandoned pits without mitigation
actions (Marchevsky et al., 2017; Zhang et al., 2018). The latter is the
case of many abandoned quarries along the Tandilia mountains.
Considering the overall context, the general objective of this study is
to accomplish a spatiotemporal analysis of habitat loss due to opencast
mining activities in the Tandilia Mountains, southern of the Pampa
ecoregion. Our specific objectives were: (1) to identify the locations
where quarrying takes place, (2) to determine the area of active and
inactive quarries, their expansion speed, and their evolution over the
last 20 years, and (3) to assess the impact of the extractive activity
on the landscape. These objectives are achieved by processing satellite
images with Geographic Information Systems.
MATERIALS AND METHODS