Pine wilt disease (PWD) severely damages the health, stability, and functions of pine forests. However, empirical evidence regarding the impact of PWD on multiple ecosystem services in these forest ecosystems remains limited. This study investigated five ecosystem services, namely carbon sequestration, water conservation, soil nutrient accumulation, biomass nutrient accumulation and understory plant diversity in subtropical Masson pine (Pinus massoniana) forests, and quantified their trade-offs along varying ages of PWD infection (uninfected (0 years), 6, 10, and 16 years). The results showed that PWD infection significantly affected ecosystem services in Masson pine forests, with decreased carbon sequestration, water conservation, and biomass nutrient accumulation in 6 years of PWD infection forests. As the duration of PWD infection increased, the composite score of ecosystem services initially decreased, then increased, and finally decreased again. In contrast, soil conservation and understory plant diversity showed an initial increase, followed by a decline. Moreover, PWD infection increased the trade-offs among ecosystem services, with the highest trade-offs for 10 years of infected forests. PWD infection altered the trade-offs between understory plant diversity and other ecosystem services from low to high levels. Our results suggest that forest management should be strengthened to accelerate the recovery of ecosystem services while controlling PWD infection in these disturbed forests.

We tested the hypothesis that the number of seedlings from the soil seed bank (SSB) in forests polluted by heavy metals and disturbed by recent fires decreases. It was also assumed that the consequences of pollution and fires for the soil seed bank are additive. We estimated the number of seedlings from the SSB of pine forests located near the Karabash copper smelter (KCS) (contaminated by Cu, Zn, Pb, and Cd) and from uncontaminated forests of the Ilmen State Reserve (ISR). In both areas, samples of the forest litter and humus horizon were taken from forests recently exposed to ground fires and long-term unburned forests. Samples were exhibited from June to September, conducting seven rounds of counting seedlings. Small peculiarities of the emergence of seedlings on the samples of the forest litter and the humus horizon were established. However, the regularities of the reaction of SSB to pollution and fire disturbances did not depend on the soil horizon. The number of seedlings on substrates from contaminated forests was 5-8 times lower than the number of seedlings on substrates from background forests. A decrease in the number of seedlings on polluted substrates was accompanied by an increase in the share of dicots in the total number of seedlings. The relationship between the number of seedlings and the age of fires was not found. The additivity of the consequences of pollution and fires has also not been established. Of the two types of damage, pollution and fires, the pollution factor is of leading importance for SSBs. The results indicate a low recovery capacity of the herb-shrub layer of polluted forests.

Numerous studies have reported that treelines are moving to higher elevations and higher latitudes. Most treelines are temperature limited and warmer climate expands the area in which trees are capable of growing. Hence, climate change has been assumed to be the main driver behind this treeline movement. The latest review of treeline studies was published in 2009 by Harsch et al. Since then, a plethora of papers have been published studying local treeline migration. Here we bring together this knowledge through a review of 142 treeline related publications, including 477 study locations. We summarize the information known about factors limiting tree-growth at and near treelines. Treeline migration is not only dependent on favorable growing conditions but also requires seedling establishment and survival above the current treeline. These conditions appear to have become favorable at many locations, particularly so in recent years. The review revealed that at 66% of these treeline sites forest cover had increased in elevational or latitudinal extent. The physical form of treelines influences how likely they are to migrate and can be used as an indicator when predicting future treeline movements. Our analysis also revealed that while a greater percentage of elevational treelines are moving, the latitudinal treelines are capable of moving at greater horizontal speed. This can potentially have substantial impacts on ecosystem carbon storage. To conclude the review, we present the three main hypotheses as to whether ecosystem carbon budgets will be reduced, increased or remain the same due to treeline migration. While the answer still remains under debate, we believe that all three hypotheses are likely to apply depending on the encroached ecosystem. Concerningly, evidence is emerging on how treeline migration may turn tundra landscapes from net sinks to net sources of carbon dioxide in the future.