Influence of diversion power stations on riparian plant communities along Dicun stream China

This article used three diversion power stations with different operating years along Dicun stream of the source of Jiulong River to study the riparian plant community and discussed the impact of power station development on riparian plants. The results showed that:(1)There were significant differences in the plant diversity of herbs, shrubs and trees among all sample plots in the study area (P < 0.05).(2) The species number of the second and third diversion power stations with longer operation time was larger than that of the fourth diversion power station with short operation time.(3) The water-borne plants were concentrated in the herb layer in the influence area of the diversion power station, and the Richness, Shannon- Wiener, Simpson and Pielou indexes of water-borne plants in the study area were significantly different (P < 0.05). (4) The appearance of diversion power station leaded to the change of environmental factors, and the river depth and flow rate had significant positive correlation with the diversity index of riparian plants and water water-borne plants (P < 0.05). In general, with the increase of the operation time of the power station, the surrounding riparian plant will form a new stable community.

Changing climate requires shift from refugia to sanctuaries for floodplain forests

Context Riparian areas are considered to undergo major alterations under changing climate, making floodplain habitats targets for conservation and landscape planning. Protected areas might provide sanctuaries especially for sessile riparian plant species, but these niches are not always persistent over time. Objectives We investigate if plant species of floodplain forests are provided with suitable habitat within currently protected areas and if these refugia persist. A coupled-modelling approach is used to gain spatially explicit information on new areas for sanctuaries. Methods We use species distribution models to predict the niche of 12 Salicion albae and 7 Fraxinion floodplain forest species along rivers in Switzerland, under current, moderate and extreme climate change scenarios up to 80 years to the future (2100). The spread of plant species from current habitat to suitable future habitat is simulated using dispersal vectors and life history traits. Results Salicion albae species are more flexible under both climate change scenarios than Fraxinion species. The main limitation for the spread of species is their dispersal ability, as only a minority of the suitable cells is colonized during the simulation process. The predicted future presence within currently protected areas decreases under both climate change scenarios in the model. Conclusions Current protected floodplains do not provide persistent refugia for the plants studied, but might still be of importance to other organisms. Planning of sanctuaries for riparian plant species and communities need to focus on connectivity along rivers to maintain viable source populations in dynamic riverine landscapes under changing climate.

A hierarchical approach linking hydraulic and ecological modeling for habitat predictions for riverine pioneer vegetation

&lt;p&gt;The distribution of sessile riparian plant species and their habitats along riverways are highly dependent on river dynamics and connectivity. River restoration and conservation of riparian plant species rely on expert knowledge and more recently also on modelling approaches to predict species&amp;#8217; occurrence. Ecological modelling on habitat suitability for terrestrial species is usually based on climatic and topographic features, whilst river hydrodynamics is rarely considered.&lt;/p&gt;&lt;p&gt;Our study aims at predicting suitable habitat for a characteristic pioneer species for dynamic riverine habitats, the German Tamarisk (&lt;em&gt;Myricaria&lt;/em&gt; &lt;em&gt;germanica&lt;/em&gt;). Habitat predictions are tested in a case study on a floodplain along Moesa river in canton Grisons in South-East Switzerland. We link two modeling approaches having two different spatial scales using a hierarchical process. First, we define a large-scale habitat suitability matrix based on climatic, geological and topographic predictors. Using a two-dimensional hydrodynamic model, inundation frequency maps and flood level maps for several significant months for German Tamarisk establishment are constructed, to further refine the niche for the riparian plant.&lt;/p&gt;&lt;p&gt;The predicted habitat suitability is evaluated with species presence data for both adult and offspring plants. Our results allow gaining insights into the importance of linking ecological and hydraulic models having different spatial and temporal scales, for more refined predictions of riparian species distribution.&lt;/p&gt;