INTRO: By using data from national forest inventories the authors have found evidence of altered species composition and function in northern forest understory plant communities from anthropogenic stressors such as intensified forest management, eutrophication and climate change.
MERITS: + interesting that data from National Forest Inventories (NFI) can be used for predicting large-scale effect in ecosystems.
+ most pronounced effects was found in areas with the highest anthropogenic impact, with high nitrogen deposition and intensive land-use change.
+ higher effects was found in higher trophic levels influencing nutrient dynamics and possibly ecosystem productivity etc.
+ good language, well-written, comprehensible.
CRITIQUE: none
DISCUSSION: important work showing quite dramatic effects of forest in Sweden from climate change and other antropogenic effects.
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INTRO: Northern forests are under increasing anthropogenic impact, which affects their ecosystem functions and services. This study investigated how species composition and function of pristine boreal forests in Sweden have changed due to increased anthropogenic impact. The results demonstrate that during the past half century, the forest understory vegetation has overgone drastic changes linked nitrogen deposition and land-use changes.
MERITS: The abstracts greatest merit of many is its important and interesting topic regarding global changes affecting ecosystems. Another impressive merit is the temporally extensive data provided by the National Forest Inventories, which makes the results robust.
CRITIQUE: I recommend rephrasing few sentences, for making the message more clear and objective (please find the file attached with "Track changes"). Otherwise, the abstract is very good.
DISCUSSION: As said, this is an important and interesting topic regarding global changes affecting ecosystems. The burning research question combined together with the long-term data provides us insights into the consequences of anthropogenic impact on the largest biome of the world. This information can be implied on both forest management and forest conservation. In addition, this study will inspire more research on this important matter.
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INTRO: The abstract outlines an interesting study using a Swedish national forestry database including species composition combined with plant trait data and environmental data to address questions surrounding human impact on semi-wild forest communities.
MERITS: The study approach coupling human drivers, species and traits is a novel one and more should be made of selling this approach.
CRITIQUE: There is a jumble of environemntal factors influencing the understorey community here - the introduction outlines a climate gradient, nitrogen deposition and forest land use. The story can be streamlined more so that only the main factors influencing the community are mentioned in the abstract.
It is not necessary to justify why Sweden in the abstract - this will save some words from the methods, so the results can be explained more.
It is not clear in the methods where the trait data came from? Was it collected as part of the Forestry inventory data?
The statement 'All these effects were most pronounced in areas with the highest anthropogenic impact, suggesting a link to drivers such as nitrogen deposition and land-use changes' is unclear. Was species composition change positively correlated with N depsoition and what landuse changes resulted in greatest change of species? Please specify.
DISCUSSION: The below statement is a bit speculative given that only species composition and traits have been measured and no processes i.e. decomposition between the two time points may change due to changes in N availability rather than species/trait change per se. How has this been uncouple? It is better to keep the results broad and highlight the strength of the approach of looking at the impact of human drivers on species and traits.
"Possible associated changes in ecosystem functions and services include effects on higher trophic levels and higher decomposition rates of plant litter in the expanding vegetation types, which can influence nutrient dynamics, with subsequent effects on ecosystem productivity and C sequestration."
What do the results mean for forest management? Is there spatial explicit/context dependency for forest management for plant biodiversity/ecosystem functioning?