INTRO: The authors present a multi-taxa biodiversity assessment across forested and agricultural landscapes in northern and north-eastern China over the last decade. Their results suggest that rural exodus and environmental policies in China may represent an opportunity to bolster rural biodiversity and associated ecosystem service provision.
MERITS: The manuscript convincingly argues for the importance of studying the impacts of environmental policy on biodiversity patterns in rural China. Multi-taxa assessments across multiple land-cover types seem to be an appropriate means to achieve this aim.
CRITIQUE: By devoting half of the abstract to background and justification of the study, the authors leave little room to describe the methods and results of the study.
The abstract background offers the tantalising prospect that the authors will directly assess the impacts on biodiversity of environmental policy and human population movements over time. The methods and results indicate that the authors have compared multi-taxa assemblages between land-cover types. The authors do not mention if they have attempted to directly assess the impacts of policy, for example by comparing sites where habitat restoration has been undertaken or tree plantations have been established, with appropriately paired sites where unmanaged succession has taken place.
The authors do not offer the counter-argument (to the importance of secondary and plantation forests) that mature forests may harbour biodiversity not found in any other land-cover type.
DISCUSSION: The potential for Chinese government environmental policy to impact biodiversity on a large scale merits detailed study in itself. Reforestation could provide multiple benefits to both biodiversity and to human communities. Inappropriately planned and executed projects could however lead to biotic homogenisation and ecosystem degradation, for example in cases where non-native monocultures replace species-rich habitat mosaics. This research, which assesses the impacts of Chinese government environmental policy, is welcome. Moreover, continued global biodiversity loss and climatic change have prompted conservationists to consider placing a stronger emphasis on interventionist ecosystem restoration. The merits of this approach relative to preserving currently biodiverse regions, is a globally important issue which conservationists must consider.
- - -
INTRO: The manuscript describes what the effect is of reforestation campaigns on biodiversity in northern and north-eastern China.
MERITS: Given the unprecedented urbanisation across the globe, the positive and negative side-effects of urbanisations are a frequent topic of discussion. This manuscript illustrates a positive side-effect of urbanisation; namely the abandonment of agricultural landscapes and the opportunities for nature restoration that arise there. The authors show that this restoration can lead to an increase in biodiversity. Such success stories usually receive too little attention and deserve to be made public.
CRITIQUE: The abstract is well-written, clear and concises. As far as I can judge from the details given in this abstract, I see no weaknesses in the manuscript.
DISCUSSION: Rural abandonment and urbanisation are happening all across the globe and there is much ongoing discussion how to biodiversity can potentially profit from these trends. I therefore think that this manuscript addresses and important and actual topic. As a potential improvement of the research I would suggest the authors to elaborate on the effects of reforestation on food production in China. Will the loss in productive agricultural land be compensated with more intensive and potentially more polluting agriculture? Or will more food be imported from abroad, thereby exporting the problems associated to agricultural production to other countries?