Effects of snow manipulation on larch trees in the taiga forest ecosystem in northeastern Siberia

Changes in winter precipitation (snow) may greatly affect vegetation by altering hydrological and biochemical processes. To understand the effects of changing snow cover depth and melt timing on the taiga forest ecosystem, a snow manipulation experiment was conducted in December 2015 at the Spasskaya Pad experimental larch forest in Eastern Siberia, which is characterized by a continental dry climate with extreme cold winters and hot summers. Variables including soil temperature and moisture, oxygen and hydrogen isotope ratios of soil moisture and stem water, foliar nitrogen and carbon contents and their isotopes, phenology, and soil inorganic nitrogen were observed at snow removal (SNOW−), snow addition (SNOW+), and CONTROL plots. After snow manipulation, the soil temperature at the SNOW− plot decreased significantly compared to the CONTROL and SNOW+ plots. At SNOW− plot, snowmelt was earlier and soil temperature was higher than at other plots during spring because of low soil moisture caused by less snowmelt water. Despite the earlier snowmelt and higher soil temperature in the SNOW− plot in the early growing season, needle elongation was delayed. Leaf chemistry also differed between the CONTROL and SNOW− plots. The needle nitrogen content in the SNOW− plot was lower in the middle of July, whereas no difference was observed among the three plots in August. The soil inorganic nitrogen content of each plot corresponded to these results. The amount of soil ammonium was lower in the SNOW− plot than in the other plots at the end of July, however, once production started in August, the amount of soil ammonium in the three plots was comparable. Extremely low soil temperatures in winter and freeze–thaw cycles in spring and dry soil condition in spring and early summer at the SNOW− plot may have influenced the phenology and production of soil inorganic nitrogen.

Ecological restoration through natural regeneration in Chunati Wildlife Sanctuary – a protected area of South-East Bangladesh

PurposeIn this paper, the authors show that ecological restoration potential through natural regeneration of degraded tropical rainforest is possible. This is significant because at present most of the tropical forest of the world, including of Bangladesh, are degraded.Design/methodology/approachRegeneration status of Chunati Wildlife Sanctuary (CWS) was assessed through stratified random sampling method using sample plots of 5 × 5 m in size covering 269 sample plots.FindingsA total of 3,256 regenerating seedlings/saplings of 105 species belonging to 35 families were recorded from CWS. From regenerating tree species, maximum (37.83) family importance value (FIV) index was found for Euphorbiaceae followed by Myrtaceae (18.03). Maximum importance value index (IVI) was found for Aporosa wallichii (21.62) followed by Grewia nervosa (16.41). Distribution of seedlings into different height classes of regenerating tree species was also calculated.Practical implicationsForest scientists are working to find out the best nature-based solution for ecological restoration of tropical rainforests to attain climate resilient ecosystem in a sustainable way. Tropical rain forest has huge plant diversity, and we find that ecological restoration is possible through natural regeneration from its rich soil seed bank. Natural regeneration is the best nature-based solution for sustainable management of the forest.Social implicationsThe authors believe that the findings presented in our paper will appeal to the forest and environmental scientists. The findings will allow readers to understand degraded tropical hill forest ecosystem and its management strategy.Originality/value The authors believe that this manuscript will give a clear picture about degraded tropical hill forest ecosystem and its genetic composition, diversity and soil seed bank status to apply appropriate management strategy.

The first epiphytic macrolichen and its implication to the interacting with Mesozoic forest ecosystem

Lichens are well known as pioneer organisms or stress-tolerant extremophiles playing a core role in the early formation of terrestrial ecosystems, of which epiphytic lichens make a distinct contribution to the water-cycle and nutrient cycling in forest ecosystem. But due to the scarcity of relevant fossil records, the evolutionary history of epiphytic lichens is poorly documented. Herein, based on the new material of Daohugouthallus ciliiferus, we demonstrated that the hitherto oldest macrolichen inhabited a gymnosperm branch, representing the first unambiguous Jurassic epiphytic lichen. Combing the fossil and extant macrolichen representatives, we performed the geometric morphometric analysis and comprehensive comparison to infer the systematic status of this rare Jurassic macrolichen. The results declared that D. ciliiferus cannot be assigned to any known macrolichen lineages for its elder age and particular habits, and therefore a new family, Daohugouthallaceae was proposed. This work updated the current knowledge to the historical evolution of epiphytic lichens, implying the macrolichens may have diversified much earlier than the generally accepted K–Pg boundary. In addition, our new finding also provided direct evidence for tracing the continuing joint development of epiphytic lichens and forest ecosystem since the Jurassic of 165 Mya.

DIVERSITY, DISTRIBUTION AND ABUNDANCE OF LICHEN IN SIMILIPAL BIOSPHERE RESERVE, ODISHA

Lichens are organized symbionts that have their importance due to a potential indicator of the forest ecosystem. The lichen diversity of Odisha is not well explored as compared to the other phytogeographical region of India. Though the earlier study reported the occurrence of 252 lichen species from different parts of the state, it was limited to the northeast part of the Similipal Biosphere Reserve (SBR). The objective of the present study was to survey some unexplored areas of SBR, which revealed the occurrence of 84 species of lichens belonging to 38 families and 18 genera. Most of the lichens were found growing as phorophytes on the matured bark of the trees. The western part of the SBR is rich in lichen diversity as compared to the eastern part. Species frequency was found to be highest in the southwest part of the SBR, while the density and abundance were more or less similar within all the study sites. The correlation between frequency and density was found to be significant and insignificant between frequency and abundance.