Abstract. Management of native forests offers opportunities to store more carbon in the land sector through two main activities. Emissions to the atmosphere can be avoided by ceasing logging. Removals of carbon dioxide from the atmosphere can be increased by allowing forests to continue growing. However, the relative benefits for carbon storage of managing native forests for wood production versus protection are contested. Additionally, the potential for carbon storage is impacted upon by disturbance events, such as wildfire, that alter the amount and longevity of carbon stocks.Using a case study of montane ash forests in southeastern Australia, we demonstrated that the total biomass carbon stock in logged forest was 55% of the stock in old growth forest. Total biomass included above-and belowground, living and dead. Biomass carbon stock was calculated spatially as an average across the landscape, accounting for variation in environmental conditions and forest age distribution. Reduction in carbon stock in logged forest was due to 66% of the initial biomass being made into products with short lifetimes (,3 years), and to the lower average age of logged forest (,50 years compared with .100 years in old growth forest). Only 4% of the initial carbon stock in the native forest was converted to sawn timber products with lifetimes of 30-90 years.Carbon stocks are depleted in a harvested forest system compared with an old growth forest, even when storage in wood products and landfill are included. We estimated that continued logging under current plans represented a loss of 5.56 Tg C over 5 years in the area logged (824 km 2 ), compared with a potential gain of 5.18-6.05 TgC over 5 years by allowing continued growth across the montane ash forest region (2326 km 2 ). Avoiding emissions by not logging native forests and allowing them to continue growing is therefore an important form of carbon sequestration. The mitigation value of forest management options of protection versus logging should be assessed in terms of the amount, longevity and resilience of the carbon stored in the forest, rather than the annual rate of carbon uptake.

The value for biodiversity of large intact areas of native vegetation is well established. The biodiversity value of regrowth vegetation is also increasingly recognised worldwide. However, there can be different kinds of revegetation that have different origins. Are there differences in the richness and composition of biotic communities in different kinds of revegetation? The answer remains unknown or poorly known in many ecosystems. We examined the conservation value of different kinds of revegetation through a comparative study of birds in 193 sites surveyed over ten years in four growth types located in semi-cleared agricultural areas of south-eastern Australia. These growth types were resprout regrowth, seedling regrowth, plantings, and old growth. Our investigation produced several key findings: (1) Marked differences in the bird assemblages of plantings, resprout regrowth, seedling regrowth, and old growth. (2) Differences in the number of species detected significantly more often in the different growth types; 29 species for plantings, 25 for seedling regrowth, 20 for resprout regrowth, and 15 for old growth. (3) Many bird species of conservation concern were significantly more often recorded in resprout regrowth, seedling regrowth or plantings but no species of conservation concern were recorded most often in old growth. We suggest that differences in bird occurrence among different growth types are likely to be strongly associated with growth-type differences in stand structural complexity. Our findings suggest a range of vegetation growth types are likely to be required in a given farmland area to support the diverse array of bird species that have the potential to occur in Australian temperate woodland ecosystems. Our results also highlight the inherent conservation value of regrowth woodland and suggest that current policies which allow it to be cleared or thinned need to be carefully re-examined.

Aim To quantify at multiple spatial scales: (1) spatial dependence in several measures of aggregate bird biodiversity, (2) the role of native vegetation cover in explaining variation in aggregate bird biodiversity and (3) relationships between change over 8 years in bird diversity and changes in native vegetation.Location South-eastern Australia.Methods We gathered data on birds between 2002 and 2010 on 184 (2 ha) sites nested within 46 (1000 ha) farms nested within 23 (10,000 ha) landscapes. We statistically estimated spatial and temporal components of variation at the landscape, farm and site scale for several composite indices of bird diversity. Second, we modelled the relationships between aggregate bird biodiversity and log % of native vegetation cover at each spatial scale and over time.Results Variation in bird biodiversity at the landscape, farm and site scale exhibited significant, intrinsic scale-specific effects. This dependence was largely accounted for by native vegetation cover with aggregate biodiversity increasing with increasing native vegetation cover at each spatial scale and over time. Every doubling of % cover resulted in an increase of 3.1, 2.3 and 0.7 species per landscape, farm and site, respectively. Similar statistically significant positive relationship between proxy abundance and richness of species of conservation concern and % cover of vegetation were also found. Species richness at the site scale also was related to vegetation cover in the surrounding landscape. Over the period of study, relationships between changes in bird biodiversity and changes in vegetation cover were not statistically significant.Main conclusions We used 'diminishing returns' response curves to model relationships between measures of bird biodiversity and vegetation cover at all spatial scales. Absolute gains in biodiversity per unit increase in vegetation cover were greatest at relatively low amounts of vegetation cover. These results can help prioritize investment strategies such as replanting native vegetation under agri-environment schemes.

AimTo quantify changes over a 15-year period in bird functional diversity within woodland patches where woodland patches remained unchanged, but the surrounding landscape context has been altered by exotic plantation establishment.Location South-eastern Australia.Methods Using statistical modelling and principal coordinate analysis, we explored how a suite of functional diversity measures, bird species richness and the composition of the bird assemblage changed over time and in response to key covariates, including time since plantation establishment, woodland patch size, number of woodland patch boundaries surrounded by plantation and woodland vegetation type. ResultsThere was no significant change in species richness over time (with woodland patch size being the only significant effect on this measure). In contrast, we identified marked changes in the composition of bird assemblages, as well as significant temporal changes in functional diversity. The most substantial declines in functional diversity occurred in woodland patches completely surrounded by long-established stands of radiata pine. Plantation age also affected the functional diversity of bird assemblages through attracting new (typically closed forest-associated) species to the region. We also found reduced overlap in the amount of functional trait space defined by sets of species surveyed in successive years. This was linked to a shift away from solitary or pairforming species found in open-woodland environments and which consume seeds and various other food resources, towards insectivorous, nectarivorous and closed forest-associated taxa that occur in flocks or groups.Main Conclusions Examination of temporal changes in functional diversity added new insights into the biotic changes associated with landscape transformation and the functional role of species being replaced.