1,721,041 research outputs found
Vegetation as an ecological indicator of surface instability in rock glaciers
No full textWe studied relationships between vegetation, substrate texture, and surface movement
velocity in two active rock glaciers in the Central Alps (northern Italy). We also compared
the vegetation on the two active rock glaciers with that of adjacent stable areas and with
that of an inactive rock glacier. The vegetation patterns on the two active rock glaciers
differed sharply from those on the stable areas nearby and on the inactive rock glacier with
respect to both total plant cover and floristic composition. Surface movement on the two
active rock glaciers ranged from 0-5 to 35-40 cm yr.1 and was largely independent
of slope inclination. The most unstable sites were almost free of mosses and lichens and
were characterized by vascular species tolerating surface instability in virtue of varying
morphological adaptations. However, the distributional pattern of vascular species could
not be directly related to surface instability but depended on a combination of substrate
texture and movement intensity
Long-term monitoring of vegetation dynamics and carbon dioxide exchange in alpine peatlands
No full textHabitat di transizione e specie a rischio di estinzione: Kosteletzkya pentacarpos (L.) Ledeb.
No full textLa stretta interazione tra le terre emerse e il mare che caratterizza i territori del Delta del Po, antico e moderno, determina la formazione di una ricca varietà di habitat naturali di transizione, modellati e influenzati sia da fattori marini che terrestri. Si tratta di ambienti fragili particolarmente interessati dal cambiamento climatico con perdita di ecosistemi naturali per erosione, inondazione e invasione di specie alloctone (IPCC, 2021). Per questi motivi le aree di transizione sono sottoposte ad un elevato regime di tutela sia a livello nazionale che europeo (Riserve Naturali dello Stato, S.I.C., Z.P.S., Zone Ramsar, Parchi), per garantire il rispetto della biodiversità ambientale, delle specie animali e vegetali. È questo infatti l’habitat di specie altamente specializzate in grado di adattarsi alla variabilità dei fattori ambientali e di specie rare sia per la loro limitata diffusione naturale sia per la contrazione del loro areale dovuto per lo più a cause antropiche. Ne è un esempio Kosteletzkya pentacarpos (L.) Ledeb. o ibisco litorale, specie ritenuta estinta in Emilia-Romagna e ritrovata nel 2012 nei canneti e nei prati umidi delle Riserve Naturali “Po di Volano” e “Bosco della Mesola” (nel 2013), in provincia di Ferrara
Obiettivo 15: "vita sulla terra": Considerazioni sulla biodiversità vegetale della provincia di Ferrara
No full textViene presentato lo stato delle conoscenze della biodiversità vegetale per la provincia di Ferrara in relazione al Goal 15 Vita sulla Terra. I focus riguardano principalmente il Parco del Delta del Po con un approfondimento sulla Riserva Naturale del Bosco della Mesola e il ruolo degli Orti Botanic
Bedrock geology interacts with altitude in affecting leaf growth and foliar nutrient status of mountain vascular plants
No full textAims: Altitude is often used as a proxy for ascertaining how warming affects plant growth and leaf level properties. However, we have a poor understanding of how the effects of altitude-related warming varies across geology. Therefore, this study examined the independent and interactive effects of altitude and geology and species on plant growth and foliar nutrient status. Methods: We determined leaf growth rates and concentrations of major nutrients (nitrogen, N and phosphorus, P) in leaves of five species across two altitudinal gradients (1200-2200 m) in the Dolomites (south-eastern Alps, Italy). The two transects were located on carbonate bedrock and silicate bedrock, respectively. We also determined concentrations of inorganic and organic N and P forms in soils, and δ 15N signature in leaves and soils. Important Findings: Foliar N concentrations were unrelated to bedrock geology. The negative foliar δ 15N signature suggested that organic N was the primary source of N supply across the gradients. Foliar P concentrations were strongly affected by bedrock geology and their altitudinal patterns depended on the concentrations of organic and inorganic P forms in the soil. Phosphates and organic P appeared to be the main sources of P supply. Leaf growth rates increased with higher altitude on silicate bedrock and decreased with higher altitude on carbonate bedrock and presented a significant positive correlation with foliar N:P. In conclusion, bedrock geology interacted with altitude in controlling the foliar nutrient status mainly owing to availability of soil Pand its effect on foliar nutrient stoichiomctry
Bedrock geology interacts with altitude in affecting leaf growth and foliar nutrient status of mountain vascular plants
No full textAims
Altitude is often used as a proxy for ascertaining how warming affects plant growth and leaf level properties. However, we have a poor understanding of how the effects of altitude-related warming varies across geology. Therefore, this study examined the independent and interactive effects of altitude and geology and species on plant growth and foliar nutrient status.
Methods
We determined leaf growth rates and concentrations of major nutrients (nitrogen, N and phosphorus, P) in leaves of five species across two altitudinal gradients (1200 – 2200 m) in the Dolomites (south-eastern Alps, Italy). The two transects were located on carbonate bedrock and silicate bedrock, respectively. We also determined concentrations of inorganic and organic N and P forms in soils, and δ 15 N signature in leaves and soils.
Important Findings
Foliar N concentrations were unrelated to bedrock geology. The negative foliar δ 15 N signature suggested that organic N was the primary source of N supply across the gradients. Foliar P concentrations were strongly affected by bedrock geology and their altitudinal patterns depended on the concentrations of organic and inorganic P forms in the soil. Phosphates and organic P appeared to be the main sources of P supply. Leaf growth rates increased with higher altitude on silicate bedrock and decreased with higher altitude on carbonate bedrock and presented a significant positive correlation with foliar N : P. In conclusion, bedrock geology interacted with altitude in controlling the foliar nutrient status mainly owing to availability of soil P and its effect on foliar nutrient stoichiometry
Intraspecific functional differences of subalpine plant species growing in low-altitude microrefugia and high-altitude habitats
No full textMountain ice holes are microrefugia at low altitudes characterized by colder temperatures compared to the surrounding areas. Ice holes harbor extra-zonal plant communities composed of plant species that generally grow at higher altitudes in subalpine habitats. Understanding how subalpine species adjust their functional traits to extra-zonal environmental conditions in ice holes can improve our knowledge of plants’ ability to cope with environmental changes. We compared the intraspecific trait variability of four species growing in ice holes and in subalpine areas in the south-eastern Alps of Italy. Plant functional traits presented different patterns of variation between the two habitats. Leaf area, leaf nitrogen and phosphorus content and stomatal traits (stomatal density and stomatal length) differed consistently between habitats in all species. Conversely, specific leaf area and leaf dry matter content varied differently between habitats depending on species. The four species developed differing strategies for adapting leaf functional traits to the peculiar environment of ice holes. Two species, Vaccinium myrtillus and Rhododendron ferrugineum, took advantage of extra-zonal location by developing a more competitive ecological strategy. Conversely, Vaccinium vitis-idaea and Homogyne alpina adopted a more conservative strategy by optimizing adaptation of leaf traits to cold temperature. Our study represents a first attempt to understand the role of marginal populations within the total functional variation of a species. We highlighted the importance of protecting ice holes as important reservoirs of functional diversity for subalpine plant species
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