Assessing the effects of agricultural intensification on natural habitats and biodiversity in Southern Amazonia

distribution range of all investigated vertebrate species could be reduced by over 99% (area- weighted change) compared to the Trend Scenario. 3.2.2. Mato Grosso. As Fig 3 shows, the assumptions made for the Trend Scenario in MT result in a strong disturbance of vertebrate species diversity. An area of 62,824 km2 of natural habitats is converted in the case of the Trend Scenario. An especially strong impact can be seen for all categories of bird species, endemic and threatened mammals and endemic amphibians. The distribution range of small-ranged mammals is slightly less affected. Small-ranged amphibian distribution ranges are least afflicted. The situa- tion concerning threatened amphibians (for all scenarios) may not be consistent with the actual situation as threatened amphibians are especially data deficient in Brazil [5]. In the case of the Legal Intensification Scenario 35,555 km2 of natural habitats were con- verted into managed land. The calculation of the area-weighted change of affected distribution ranges illustrates a reduction of 53% for all amphibian, bird and mammal taxa and categories except small ranged amphibians (-30%) and small-ranged mammals (-46%) in comparison with the Trend Scenario. Concerning the Illegal Intensification Scenario, the negative effect of a conversion of natural habitats (55,301 km2) on the distribution ranges of all investigated taxa and categories per taxon could be reduced (area-weighted change) by 44%, except small-ranged amphibians (-73%) and small-ranged mammals (-35%) despite the fact that the total converted area was

only reduced by 12% in comparison with the Trend Scenario. The assumptions made in the case of the Sustainable Development Scenario lead to a reduc- tion of converted natural habitats to 40,166 km2. The positive effect expressed as a reduction of the afflicted distribution ranges (area-weighted change) amounts to 36% for endemic amphibi- ans and mammals as well as small-ranged and threatened birds. This positive effect can also be witnessed for small-ranged amphibians (-32%), endemic birds (-44%), small-ranged (-26%) as well as threatened mammals (-38%). 3.2.3. Factors influencing natural habitat loss and the distribution ranges of vertebrate species: A scenario comparison. In MT, the area of affected natural habitats in the case of the Illegal Intensification scenario could be reduced by 12% compared to the Trend Scenario. This reduction of transformed natural habitats due to agricultural intensification is surpassed in the Legal Intensification Scenario. Here, the conversion of natural habitats could be Fig 3. Natural habitat area of investigated vertebrate species affected by conversion over total converted area in Mato Grosso. https://doi.org/10.1371/journal.pone.0225914.g003 PLOS ONE Agricultural intensification effects on natural habitats and biodiversity PLOS ONE | https://doi.org/10.1371/journal.pone.0225914 November 25, 2020 11 / 21