Environmental characteristics, including soil and vegetation composition, in relation to the occurrence patterns of an endangered lizard, Eremias argus, in a fluvial island, South Korea

Eremias argus, known as the Mongolian racerunner, is a reptile that has been designated as a level II endangered species in South Korea since 2005 despite being listed as “Least Concern” by the International Union for Conservation of Nature. Particular vegetation and soil characteristics are critical components of the habitat of E. argus, which is an ectotherm. However, research on the environmental characteristics of E. argus living on a fluvial island is lacking. This study sought to characterize the soil environmental factors and vegetation composition of E. argus habitats on Doriseom Island, South Korea by dividing the island into an area in which E. argus occurred frequently (F zone) and an area in which E. argus occurred rarely (R zone). Both soil hardness and cobble cover were significantly higher in the R zone (soil hardness: 1.6 ± 0.2 kg‧cm-2, mean ± standard error; cobble cover: 40 ± 5%) than in the F zone (soil hardness: 0.9 ± 0.1 kg‧cm-2; cobble cover: 18 ± 3%). Plant litter cover did not differ significantly based on E. argus occurrence. The vegetation composition within F and R zones appeared distinct, though Coreopsis lanceolata dominated both zones. A sand dune sedge, Carex pumila, thrived in F zone sites, where soil hardness was low, while the endemic Aster danyangensis, which prefers cobble areas, was found largely in the R zone. In conclusion, E. argus was most commonly found in areas with low soil hardness dominated by dune vegetation. Understanding endangered species’ habitat requirements can provide important clues for establishing conservation plans and restoration measures

Silvicultural management and altitude prevail on soil properties and fungal community in shaping understorey plant communities in a Mediterranean pine forest

Understorey vegetation plays a key role in Mediterranean forest ecosystem functioning. However, we still lack a thorough understanding of the patterns and drivers of understorey composition and diversity. As a result, understoreys are often ignored during assessments of forest functioning under climate change. Here we studied the effect of silvicultural management, topography, soil fungal community composition and soil physical and chemical properties on understorey community composition and diversity. The plant cover and number of individuals of understorey perennial plants, shrubs and non-dominant trees was recorded on 24 plots (paired: control-thinned) in a Mediterranean pine-dominated mountainous area in Northeast Spain. The study area represented a broad thinning intensity gradient (from 0 to 70 % in removed stand basal area) along a 400-m altitudinal range (from 609 m to 1013 m). Our results showed that thinning intensity and topography explained the greatest proportion of the total variance in the understorey species composition, i.e., 18 % and 16 %, respectively. Interestingly, the effects of the silvicultural treatments were significant only when considering the altitudinal effect, so that, the main impacts of thinning on the understorey community composition occurred at low altitudes (between 609 m and 870 m). Moreover, we found a significant decrease in both richness and abundance of understorey species in both the control and thinned plots with increasing altitude, with thinned plots being significantly richer in species compared to the control plots. The difference in the understorey community sensitivity to forest thinning along the altitudinal gradient suggests changes in factors that limit plant growth. Low elevation plots were restrained by light availability while high altitudes plots limited by winter freezing temperatureThis work was supported by the Spanish Ministry of Science and Innovation and Universities (RTI2018-099315-A-I00). Josu G. Alday was supported by Ramon y Cajal fellowship (RYC-2016-20528). José Antonio Bonet and Sergio de Miguel benefitted from a Serra-Húnter Fellowship provided by the Generalitat of Catalonia

Environmental characteristics, including soil and vegetation composition, in relation to the occurrence patterns of an endangered lizard, Eremias argus, in a fluvial island, South Korea

Eremias argus, known as the Mongolian racerunner, is a reptile that has been designated as a level II endangered species in South Korea since 2005 despite being listed as “Least Concern” by the International Union for Conservation of Nature. Particular vegetation and soil characteristics are critical components of the habitat of E. argus, which is an ectotherm. However, research on the environmental characteristics of E. argus living on a fluvial island is lacking. This study sought to characterize the soil environmental factors and vegetation composition of E. argus habitats on Doriseom Island, South Korea by dividing the island into an area in which E. argus occurred frequently (F zone) and an area in which E. argus occurred rarely (R zone). Both soil hardness and cobble cover were significantly higher in the R zone (soil hardness: 1.6 ± 0.2 kg‧cm-2, mean ± standard error; cobble cover: 40 ± 5%) than in the F zone (soil hardness: 0.9 ± 0.1 kg‧cm-2; cobble cover: 18 ± 3%). Plant litter cover did not differ significantly based on E. argus occurrence. The vegetation composition within F and R zones appeared distinct, though Coreopsis lanceolata dominated both zones. A sand dune sedge, Carex pumila, thrived in F zone sites, where soil hardness was low, while the endemic Aster danyangensis, which prefers cobble areas, was found largely in the R zone. In conclusion, E. argus was most commonly found in areas with low soil hardness dominated by dune vegetation. Understanding endangered species’ habitat requirements can provide important clues for establishing conservation plans and restoration measures

The potential habitats of two submerged macrophytes,

We examined the environmental factors that characterize the habitats of two submerged macrophytes, Myriophyllum spicatum and Hydrilla verticillata, in South Korea using generalized additive models (GAMs). We performed a vegetation survey and measured water depth and water velocity from May to September, 2014–2015. Averaged water quality data from the Ministry of Environment's national water quality measurement network from January 2012 to October 2015 were used for modeling. Potential habitats of M. spicatum were linked with chlorophyll a, nitrate nitrogen, suspended solids, water temperature, water depth, and water velocity (deviance explained = 28.7%, accuracy = 74%). In the case of H. verticillata, electrical conductivity and suspended solids were key habitat factors (deviance explained = 23.4%, accuracy = 75%). Model results were highly consistent with observations and field data. Model performances were evaluated by the accuracy rate, the area under the receiver operating characteristic curve, the kappa value, and field verification, and were in generally good agreement. Few studies have evaluated the developed models using the independent field data. By understanding the environmental factors that characterize the habitats for submerged macrophytes, our results contribute to the development of conservation and management strategies for river ecosystems

The potential habitats of two submerged macrophytes, Myriophyllum spicatum and Hydrilla verticillata in the river ecosystems, South Korea

We examined the environmental factors that characterize the habitats of two submerged macrophytes, Myriophyllum spicatum and Hydrilla verticillata, in South Korea using generalized additive models (GAMs). We performed a vegetation survey and measured water depth and water velocity from May to September, 2014–2015. Averaged water quality data from the Ministry of Environment's national water quality measurement network from January 2012 to October 2015 were used for modeling. Potential habitats of M. spicatum were linked with chlorophyll a, nitrate nitrogen, suspended solids, water temperature, water depth, and water velocity (deviance explained = 28.7%, accuracy = 74%). In the case of H. verticillata, electrical conductivity and suspended solids were key habitat factors (deviance explained = 23.4%, accuracy = 75%). Model results were highly consistent with observations and field data. Model performances were evaluated by the accuracy rate, the area under the receiver operating characteristic curve, the kappa value, and field verification, and were in generally good agreement. Few studies have evaluated the developed models using the independent field data. By understanding the environmental factors that characterize the habitats for submerged macrophytes, our results contribute to the development of conservation and management strategies for river ecosystems

Successional changes in plant composition over 15 years in a created wetland in South Korea

Backgrounds The main purpose of this research was to assess changes in vegetation structure, wetland index, and diversity index for a 15-year-old created wetland in Jincheon, South Korea. The created wetland consists of four sub-wetlands: a kidney-shaped wetland, a ditch, an ecological pond, and a square wetland. Vegetation and water depth data were collected at each site in 1999 and 2013, and Shannon diversity and wetland indices were calculated. Results The total number of plant species increased from 18 in 1999 to 50 in 2013, and the ecological pond in 1999 and the ditch in 2013 presented the highest diversity indices (2.5 and 3.2, respectively). Plant species were less diverse in 1999 than in 2013, presumably because these initial wetlands were managed periodically for water purification and installation of test beds. The proportion of wetland plants, including obligate wetland and facultative wetland species, decreased from 83 to 56%, whereas upland plants, including obligate upland and facultative upland species, increased from 17 to 44%. After ceasing water supply, water depth in all four sub-wetlands declined in 2013. Thus, upland plants established more readily at these sites, resulting in higher diversity and lower wetland indices than in 1999. Conclusions The major floristic differences between 1999 and 2013 were an increase in the number of upland plants and a decrease in wetland species. Although wetland indices were lower in 2013, the created wetland performed important ecosystem functions by providing habitats for wetland and upland plants, and the overall species diversity was high

Silvicultural management and altitude prevail on soil properties and fungal community in shaping understorey plant communities in a Mediterranean pine forest

Understorey vegetation plays a key role in Mediterranean forest ecosystem functioning. However, we still lack a thorough understanding of the patterns and drivers of understorey composition and diversity. As a result, understoreys are often ignored during assessments of forest functioning under climate change. Here we studied the effect of silvicultural man-agement, topography, soil fungal community composition and soil physical and chemical properties on understorey com-munity composition and diversity. The plant cover and number of individuals of understorey perennial plants, shrubs and non-dominant trees was recorded on 24 plots (paired: control-thinned) in a Mediterranean pine-dominated mountainous area in Northeast Spain. The study area represented a broad thinning intensity gradient (from 0 to 70 a/o in removed stand basal area) along a 400-m altitudinal range (from 609 m to 1013 m). Our results showed that thinning intensity and topography explained the greatest proportion of the total variance in the understorey species composition, i.e., 18 a/o and 16 a/o, respectively. Interestingly, the effects of the silvicultural treatments were significant only when considering the altitudinal effect, so that, the main impacts of thinning on the understorey community composition occurred at low altitudes (between 609 m and 870 m). Moreover, we found a significant decrease in both richness and abundance of understorey species in both the control and thinned plots with increasing altitude, with thinned plots being signifi-cantly richer in species compared to the control plots. The difference in the understorey community sensitivity to forest thinning along the altitudinal gradient suggests changes in factors that limit plant growth. Low elevation plots were restrained by light availability while high altitudes plots limited by winter freezing temperature