Restoration of Neotropical grasslands degraded by quarrying using hay transfer

Abstract

AbstractAimThe campos rupestres are species‐rich tropical mountain grasslands in southeast Brazil that are threatened by mining and quarrying. Eight years following a strong disturbance (i.e. quarrying for gravel exploitation during the asphalting of highway MG‐010), spontaneous succession did not occur on degraded areas. This study was therefore designed to test the restoration technique of hay transfer as a means of enhancing seed dispersal from the reference ecosystems to the degraded areas.LocationCampo rupestre grasslands, Serra do Cipó, Minas Gerais, Brazil.MethodsNine degraded areas representing three kinds of substrate (latosol, sandy and stony) were selected. Hay transfer was carried out using hay collected in two kinds of grassland (i.e. campos arenosos and campos pedregosos) year‐round in 2010, in order to maximize the seed pool. The collected hay was distributed on 40 cm × 40 cm quadrats among the three types of substrate, with and without geotextile, according to the following protocol: hay from campo arenoso grasslands was spread on all types of substrate, while hay from campo pedregoso grasslands was used on stony substrate only.ResultsFew seedlings emerged within 14 mo of the treatment application, despite the large number of seeds contained in the hay, indicating that hay transfer may not be a useful method for restoring degraded areas of campos rupestres. The seedlings emerging on the degraded areas mainly belonged to ruderal species. Therefore, we suggest that, although poor soil conditions could limit seedling establishment, germination issues of the campo rupestre species are the first limitation for restoring degraded campos rupestres using hay transfer.ConclusionOur results highlight the inherent difficulty in restoring degraded areas of campos rupestres; their protection must be made a high conservation priority.