| 1. |
- Sandström, Jennie, et al.
(författare)
-
Impacts of dead-wood manipulation on the biodiversity of temperate and boreal forests - A systematic review
- 2019
-
Ingår i: Journal of Applied Ecology. - : Wiley. - 0021-8901 .- 1365-2664. ; 56:7, s. 1770-1781
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Dead wood (DW) provides critical habitat for thousands of species in forests, but its amount, quality and diversity have been heavily reduced by forestry. Therefore, interventions aiming to increase DW might be necessary to support its associated biodiversity, even in protected forests, which may be former production forests. Our aim was to synthesize the current state of knowledge drawn from replicated experimental studies into solid quantitative evidence of the effects of DW manipulation on forest biodiversity, with a focus on protected forests.We conducted a full systematic review of effects of DW manipulation on forest biodiversity in boreal and temperate regions. We included three intervention types: creation of DW from live trees at the site, addition of DW from outside the site and prescribed burning. Outcomes included abundance and species richness of saproxylic insects, ground insects, wood-inhabiting fungi, lichens, reptiles and cavity-nesting birds. In total, we included 91 studies, 37 of which were used in meta-analyses. Although meta-analysis outcomes were heterogeneous, they showed that increasing the amount of DW (“DW enrichment”) has positive effects on the abundance and richness of saproxylic insects and fungi. The positive effect on saproxylic pest insect abundance tended to be less than that on saproxylic insects in general. No significant effects were found for ground insects or cavity-nesting birds.Although reviewed studies were mainly short term, our results support that management that increases DW amounts has the potential to increase the abundance of DW-dependent species and, in most cases, also their species richness. Studies of burning showed positive effects on the abundance of saproxylic insects similar to those of other interventions, even though burning on average resulted in a smaller enrichment of DW amounts.Policy implications. The findings of the review suggest that manipulating dead wood (DW) can be an effective part of conservation management to support biodiversity in protected areas. The findings also indicate that the diversity of DW types is important, a mix of DW qualities should be favoured. Burning seems to be an effective method to increase biodiversity but to benefit cavity-nesting birds, snag losses need to be minimized.
|
|
| 2. |
- Granath, Gustaf, 1980-, et al.
(författare)
-
Trade-offs in berry production and biodiversity under prescribed burning and retention regimes in boreal forests
- 2018
-
Ingår i: Journal of Applied Ecology. - : Wiley. - 0021-8901 .- 1365-2664. ; 55:4, s. 1658-1667
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Green tree retention and prescribed burning are the practices used to mitigate negative effects of boreal forestry. Beside their effects on biodiversity, these practices should also promote non-timber forest products (NTFPs). We assessed: (1) how prescribed burning and tree retention influence NTFPs by examining the production of bilberry, Vaccinium myrtillus and cowberry, Vaccinium vitis-idaea; (2) if there are synergies or trade-offs in the delivery of these NTFPs in relation to the delivery of species richness, focusing on five groups of forest-dwelling species. We used a long-term experiment located in eastern Finland, with three different harvesting treatments: clear-cut logging, logging with retention patches and unlogged, which were combined with or without prescribed burning. Eleven years after the treatment application, we scored plant cover and berry production in different microhabitats within these treatments, while species richness data for five species groups (ground layer lichens and bryophytes, vascular plants, saproxylic beetles, pollinators?here bees and hoverflies) were collected at the stand level. Logging favoured cowberry production, particularly for plants growing in the vicinity of stumps. Logging was detrimental for cover and berry production of bilberry. Retention mitigated these negative effects slightly, but cover and berry production were still substantially lower compared to unlogged forests. Prescribed burning increased the cowberry production in retention patches and in unlogged forest. Bilberry production decreased with burning, except in unlogged forest where the effect was neutral. No single management treatment simultaneously favoured all values?NTFPs and richness?and trade-offs among values were common. Only bilberry production and beetle diversity were higher under retention forestry, or in unlogged stands, compared to logged stands. Prescribed burning favoured many values when performed in combination with retention forestry, or in unlogged stands, but different treatment combinations favoured different species groups. Synthesis and applications. Our results demonstrate that widely applied conservation practices in managed boreal forests are unlikely to benefit all ecosystem values everywhere. If high multifunctionality is desired, managing at a landscape scale, countering the local trade-offs among values, may be more appropriate than the stand-scale conservation practices commonly practiced today.
|
|
