Climatic oscillations in Quaternary have shaped the co-evolutionary patterns between the Norway spruce and its host-associated herbivore

Demographic and ecological niche dynamics of the Vietnam warty newt, Paramesotriton deloustali: Historical climate influences

Quaternary climatic cycles strongly affected the genetic diversification and ranges of organisms, shaping current genetic structures and distribution patterns. Urodeles provide ideal examples for exploring these dynamics over time and across space. In this study, we integrated a phylogeographic approach and ensemble species distribution modeling (eSDM) to infer the historical demography and distribution patterns of the Vietnam warty newt, Paramesotriton deloustali. Mitochondrial data revealed two groups, West and East, which diverged approximately 1.92 million years ago (Mya). Diversification was likely driven by change in the climate during early stages of the Pleistocene, with increasing monsoon and drought intensities. Biogeographic analysis indicated that the newt's current distribution formed as a result of vicariance events. In addition, the two groups occupy distinct ecological niches. Demographic reconstruction showed signs of expansion in the effective population sizes of the two major groups beginning around 0.11 and 0.15 Mya, respectively. However, eSDM showed fluctuating predicted distributions during the last interglacial, last glacial maximum, mid-Holocene, and present. Mountain systems in northern Vietnam are likely to have served as climatic refuges and to have played a crucial role in safeguarding species from the effects of climate change.

Evaluating species boundaries using coalescent delimitation in pine-killing Monochamus (Coleoptera: Cerambycidae) sawyer beetles

Plant-feeding beetle species are diverse and often individually highly variable. Accurate classifications can be difficult to establish yet are essential for study of evolutionary patterns and processes. Molecular data are key to further characterizing morphologically difficult groups and defining genus and species boundaries. Monochamus Dejean species are ecologically and economically significant, and in coniferous forests they vector the nematode that causes Pine Wilt Disease. This study uses nuclear and mitochondrial genes to test the monophyly and relationships of Monochamus and applies coalescent methods to further delimit the conifer-feeding species. Monochamus has also included approximately 120 Old World species associated with diverse angiosperm tree species. We sample from these additional morphologically diverse species to determine their placement in the Lamiini. Through supermatrix and coalescent methods, the higher-level relationships of Monochamus show that conifer-feeders are a monophyletic group that includes the type species and has split into Nearctic and Palearctic clades. Molecular dating indicates a single dispersal of conifer-feeders to North America over the second Bering Land Bridge circa 5.3 Ma. All other Monochamus sampled fall in different parts of the Lamiini tree. Small-bodied angiosperm-feeding Monochamus group with the monotypic genus Microgoes Casey. The African Monochamus subgenera sampled are distantly related to the conifer-feeding clade. The multispecies coalescent delimitation methods BPP and STACEY delimit 17 conifer-feeding Monochamus species for a total of 18 species, and supports the retention of all current species. An interrogation with nuclear gene allele phasing reveals that unphased data can be unreliable for accurate delimitations and divergence times. The delimited species are discussed with integrative evidence, highlighting real-world challenges in recognizing the completion of speciation trajectories.

The evaluation of hazardous element content in the needles of the Norway spruce (Picea abies L.) that originated from anthropogenic activities in the vicinity of the native habitats

The aim of this research was to quantify the content of hazardous elements in the needles of Norway spruce (Picea abies L.) in the natural habitats that were accumulated from thermal power plants, mines, and metal processing industry. Fifteen natural populations of the Norway spruce were sampled from the mountain ranges in Southeastern Europe (Dinaric Alps and Balkan Mountains). Two-year-old spruce needles were evaluated the content of the following hazardous elements: heavy metals cadmium, mercury, nickel, lead and zinc, and metalloid arsenic. The effect of the distance between air pollution emitters and the Norway spruce natural habitats on the hazardous elements content in needles was also evaluated. The results of the analysis of variance confirmed interpopulation differences in the content of all analyzed hazardous elements. The effect of the air pollution source (thermal power plants, mines, and industry) on the content of hazardous elements in the spruce needles was also assessed. Significant correlation was found between the distance of air pollution emitters and the amount of zinc. This study could serve as the startup point of future monitoring programs and provide new prospect of using Norway spruce needles as the bioindicator of air pollution with hazardous elements on Balkan Peninsula since the fact that the Norway spruce natural populations inhabit wide geographic range of the continental Europe, from the Balkan Peninsula, over European Alps to Scandinavia and a large-scale of altitude from 980 to 1860 m above sea level.

The evolutionary heritage and ecological uniqueness of Scots pine in the Caucasus ecoregion is at risk of climate changes

Scots pine is one of the most widely occurring pines, but future projections suggest a large reduction in its range, mostly at the southern European limits. A significant part of its range is located in the Caucasus, a global hot-spot of diversity. Pine forests are an important reservoir of biodiversity and endemism in this region. We explored demographic and biogeographical processes that shaped the genetic diversity of Scots pine in the Caucasus ecoregion and its probable future distribution under different climate scenarios. We found that the high genetic variability of the Caucasian populations mirrors a complex glacial and postglacial history that had a unique evolutionary trajectory compared to the main range in Europe. Scots pine currently grows under a broad spectrum of climatic conditions in the Caucasus, which implies high adaptive potential in the past. However, the current genetic resources of Scots pine are under high pressure from climate change. From our predictions, over 90% of the current distribution of Scots pine may be lost in this century. By threatening the stability of the forest ecosystems, this would dramatically affect the biodiversity of the Caucasus hot-spot.

The Threat of Pests and Pathogens and the Potential for Biological Control in Forest Ecosystems

Forests are an essential component of the natural environment, as they support biodiversity, sequester carbon, and play a crucial role in biogeochemical cycles—in addition to producing organic matter that is necessary for the function of terrestrial organisms. Forests today are subject to threats ranging from natural occurrences, such as lightning-ignited fires, storms, and some forms of pollution, to those caused by human beings, such as land-use conversion (deforestation or intensive agriculture). In recent years, threats from pests and pathogens, particularly non-native species, have intensified in forests. The damage, decline, and mortality caused by insects, fungi, pathogens, and combinations of pests can lead to sizable ecological, economic, and social losses. To combat forest pests and pathogens, biocontrol may be an effective alternative to chemical pesticides and fertilizers. This review of forest pests and potential adversaries in the natural world highlights microbial inoculants, as well as research efforts to further develop biological control agents against forest pests and pathogens. Recent studies have shown promising results for the application of microbial inoculants as preventive measures. Other studies suggest that these species have potential as fertilizers.