Search results for "LATITUDINAL GRADIENTS"
showing 3 items of 3 documents
Spatio‐temporal patterns of tree growth as related to carbon isotope fractionation in European forests under changing climate
2019
Aim The aim was to decipher Europe‐wide spatio‐temporal patterns of forest growth dynamics and their associations with carbon isotope fractionation processes inferred from tree rings as modulated by climate warming. Location Europe and North Africa (30‒70° N, 10° W‒35° E). Time period 1901‒2003. Major taxa studied Temperate and Euro‐Siberian trees. Methods We characterize changes in the relationship between tree growth and carbon isotope fractionation over the 20th century using a European network consisting of 20 site chronologies. Using indexed tree‐ring widths (TRWi), we assess shifts in the temporal coherence of radial growth across sites (synchrony) for five forest ecosystems (Atlantic…
Beta diversity of stream insects differs between boreal and subtropical regions, but land use does not generally cause biotic homogenization
2021
Made available in DSpace on 2021-06-25T10:17:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-01 Previous studies have found mixed results regarding the relationship between beta diversity and latitude. In addition, by influencing local environmental heterogeneity, land use maymodify spatial taxonomic and functional variability among communities causing biotic differentiation or homogenization. We tested 1) whether taxonomic and functional beta diversities among streams within watersheds differ between subtropical and boreal regions and 2) whether land use is related to taxonomic and functional beta diversities in both regions.Wesampled aquatic insects in 100 subtropical (Brazil…
Temporal species turnover and plant community changes across different habitats in the Lake Engure Nature Park, Latvia
2014
Veģetācijas dinamikas izpētē reti ir gadījumi, kad monitoringu vienlaicīgi veic vairākās atšķirīgās ekosistēmās. Tomēr šāda veida pētījumi ļauj padziļināti izprast veģetācijas struktūras un pazīmju izmaiņu mehānismus. Šajā pētījumā aplūkotas lakstaugu stāva izmaiņas, sugu aprite un sugu skaita-laika attiecība dažādu biotopu griezumā 12 gadu periodā ILTER monitoringa stacijā Engures ezera dabas parkā. Sugu aprite laikā definēta kā atšķirība sugu sastāvā starp diviem laika periodiem. Sugu skaita-laika attiecība tika novērtēta, izmantojot slīdošo logu pieeju. Detrendētā korespondentanalīze izmantota, lai noskaidrotu ikgadējās izmaiņas sugu sastāvā. Sugu skaits un kumulatīvais skaits, kā arī da…