Plants provide fundamental support systems for life on Earth and are the basis for all terrestrial ecosystems; a decline in plant diversity will be detrimental to all other groups of organisms including humans. Decline in plant diversity has been hard to quantify, due to the huge numbers of known and yet to be discovered species and the lack of an adequate baseline assessment of extinction risk against which to track changes. The biodiversity of many remote parts of the world remains poorly known, and the rate of new assessments of extinction risk for individual plant species approximates the rate at which new plant species are described. Thus the question ‘How threatened are plants?’ is still very difficult to answer accurately. While completing assessments for each species of plant remains a distant prospect, by assessing a randomly selected sample of species the Sampled Red List Index for Plants gives, for the first time, an accurate view of how threatened plants are across the world. It represents the first key phase of ongoing efforts to monitor the status of the world’s plants. More than 20% of plant species assessed are threatened with extinction, and the habitat with the most threatened species is overwhelmingly tropical rain forest, where the greatest threat to plants is anthropogenic habitat conversion, for arable and livestock agriculture, and harvesting of natural resources. Gymnosperms (e.g. conifers and cycads) are the most threatened group, while a third of plant species included in this study have yet to receive an assessment or are so poorly known that we cannot yet ascertain whether they are threatened or not. This study provides a baseline assessment from which trends in the status of plant biodiversity can be measured and periodically reassessed.

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Background Despite its wide distribution worldwide, only 4.6% of temperate grasslands are included within systems of protected areas. In Argentina, this situation is even more alarming: only 1.05% is protected. The study area (central area of the southern Salado River basin) has a large extent of grasslands of Paspalum quadrifarium (Pq) which has been target since the middle of the last century of a variety of agricultural management practices including fire burning for cattle grazing. Methods Five binary images of presence-absence data of Pq from a 42-year range (1974–2016) derived from a land cover change study were used as base data. Morphological Spatial Pattern Analysis (MSPA), Morphological Change Detection (MCD) and Network Connectivity Analysis (NCA) were performed to the data using Guidos Toolbox (GTB) for the estimation of habitat and connectivity dynamics of the Pq patches (fragments). Results A loss of the coverage area and habitat nuclei of this grassland was observed during the study period, with some temporal oscillation but no recovery to initial states. Additional drastic reduction in connectivity was also evident in resulting maps. The number of large Pq grassland fragments (>50 ha) decreased at beginning of the study period. Also, fragmentation measured as number of components (patches) was higher at the end of the study period. The Pq pajonal nuclei had their minimum representativeness in 2000, and recovered slightly in area in 2011, but with a significant percentage increase of smaller patches (=islets) and linear elements as bridges and branches. Large corridors (mainly edge of roads) could be observed at the end of the study period, while the total connectivity of the landscape pattern drops continuously. Statistics of links shows mean values decreasing from 1974 to 2016. On the other hand, maximum values of links decreased up to 19% in 2011, and recovered to a 54% of their original value in 2016. Discussion Pq fragmentation and habitat reduction could have an impact on the ecosystem functioning and the mobility of some species of native fauna. The connecting elements of the landscape were maintained and/or recovered in percentage in 2011 and 2016. This fact, although favoring the dispersion of the present diversity in the habitat nuclei could cause degradation by an edge effect. Part of the area has the potential to be taken as an area of research and as an example of livestock management, since it is the one that would most preserve the biodiversity of the Pq environment. On the methodological side, the use of a proved tool as GTB is useful for monitoring dynamics of a grassland-habitat fragmentation.

Background. Despite its wide distribution worldwide, only 4.6% of temperate grasslands are included within systems of protected areas. In Argentina, this situation is even more alarming: only 1.05% is protected. The study area (central area of the southern Salado River basin) has a large extent of grasslands of Paspalum quadrifarium (Pq) which has been target since the last century of a variety of agricultural management practices including fire burning for cattle grazing. Methods. Binary images of presence-absence data of Pq from a 42-year (1974-2016) land cover change study were used as base data. MSPA (Morphological Spatial Pattern Analysis) and Network Analysis were performed to the data using Guidos Toolbox for the estimation of habitat and connectivity dynamics of the Pq patches (fragments). Results. A loss of the coverage area and habitat nuclei of this grassland was observed between the beginning and the end of the study period. A drastic reduction in connectivity was also evident in resulting maps. The number of large Pq grassland fragments (> 50 ha) decreased during the study period, and fragmentation measured as number of components (patches) was higher at the end of study period. The Pq pajonal nuclei had their minimum representativeness in 2000, and recovered slightly in 2011, but with a significant percentage increase of the small patches (=islets) and linear elements as bridges and branches. Large corridors (mainly edge of roads) could be observed at the end of study period, while the total connectivity of the landscape pattern drops abruptly. Discussion. The habitat reduction could have an impact on the ecosystem functioning and the mobility of some species of native fauna. The connecting elements of the landscape were maintained and/or recovered in percentage in 2011 and 2016. This fact, although favoring the dispersion of the present diversity in the habitat nuclei could cause degradation by an edge effect. On the methodological side, the use of a proved tool as Guidos Toolbox for evaluating forest fragmentation could also be useful for monitoring dynamics of a grassland-habitat fragmentation.

Background. Despite its wide distribution worldwide, only 4.6% of temperate grasslands are included within systems of protected areas. In Argentina, this situation is even more alarming: only 1.05% is protected. The study area (central area of the southern Salado River basin) has a large extent of grasslands of Paspalum quadrifarium (Pq) which has been target since the last century of a variety of agricultural management practices including fire burning for cattle grazing. Methods. Binary images of presence-absence data of Pq from a 42-year (1974-2016) land cover change study were used as base data. MSPA (Morphological Spatial Pattern Analysis) and Network Analysis were performed to the data using Guidos Toolbox for the estimation of habitat and connectivity dynamics of the Pq patches (fragments). Results. A loss of the coverage area and habitat nuclei of this grassland was observed between the beginning and the end of the study period. A drastic reduction in connectivity was also evident in resulting maps. The number of large Pq grassland fragments (> 50 ha) decreased during the study period, and fragmentation measured as number of components (patches) was higher at the end of study period. The Pq pajonal nuclei had their minimum representativeness in 2000, and recovered slightly in 2011, but with a significant percentage increase of the small patches (=islets) and linear elements as bridges and branches. Large corridors (mainly edge of roads) could be observed at the end of study period, while the total connectivity of the landscape pattern drops abruptly. Discussion. The habitat reduction could have an impact on the ecosystem functioning and the mobility of some species of native fauna. The connecting elements of the landscape were maintained and/or recovered in percentage in 2011 and 2016. This fact, although favoring the dispersion of the present diversity in the habitat nuclei could cause degradation by an edge effect. On the methodological side, the use of a proved tool as Guidos Toolbox for evaluating forest fragmentation could also be useful for monitoring dynamics of a grassland-habitat fragmentation.