Publications

This dataset contains concentrations of phenolic compounds in individual species of lichens and vascular plants sampled across an elevational gradient from 1120 to 1600 m above sea level near Finse in southern Norway.

Understanding and predicting biological invasions is challenging because of the complexity of many interacting players. A holistic approach is needed with the potential to simultaneously consider all relevant effects and effectors. Using networks to describe the relevant anthropogenic and ecological factors, from community-level to global scales, promises advances in understanding aspects of invasion from propagule pressure, through establishment, spread, and ecological impact of invaders. These insights could lead to development of new tools for prevention and management of invasions that are based on species’ network characteristics and use of networks to predict the ecological effects of invaders. Here, we review the findings from network ecology that show the most promise for invasion biology and identify pressing needs for future research.

It is axiomatic in ecology that the dynamics of one set of species cannot be understood without reference to the dynamics of other species and processes. For instance, biodiversity loss within a trophic level is likely to impact on species at other levels, whether directly through changes in competitive and consumer-resource interactions, or indirectly via changes in ecosystem processes (Fig. 13.1). Such interactions imply that predicting the consequences of biodiversity loss for ecosystem processes will be difficult, especially when, as is often the case, there are simultaneous reductions in diversity at more than one trophic level.

Boreal forests are frequently subjected to disturbances, including wildfire and clear‐cutting. While these disturbances can cause soil carbon (C) losses, the long‐term accumulation dynamics of soil C stocks during subsequent stand development is controlled by biological processes related to the balance of net primary production (NPP) and outputs via heterotrophic respiration and leaching, many of which remain poorly understood. We review the biological processes suggested to influence soil C accumulation in boreal forests. Our review indicates that median C accumulation rates following wildfire and clear‐cutting are similar (0.15 and 0.20 Mg ha −1 year −1 , respectively), however, variation between studies is extremely high. Further, while many individual studies show linear increases in soil C stocks through time after disturbance, there are indications that C stock recovery is fastest early to mid‐succession (e.g. 15–80 years) and then slows as forests mature (e.g. >100 years). We indicate that the rapid build‐up of soil C in younger stands appears not only driven by higher plant production, but also by a high rate of mycorrhizal hyphal production, and mycorrhizal suppression of saprotrophs. As stands mature, the balance between reductions in plant and mycorrhizal production, increasing plant litter recalcitrance, and ectomycorrhizal decomposers and saprotrophs have been highlighted as key controls on soil C accumulation rates. While some of these controls appear well understood (e.g. temporal patterns in NPP, changes in aboveground litter quality), many others remain research frontiers. Notably, very little data exists describing and comparing successional patterns of root production, mycorrhizal functional traits, mycorrhizal‐saprotroph interactions, or C outputs via heterotrophic respiration and dissolved organic C following different disturbances. We argue that these less frequently described controls require attention, as they will be key not only for understanding ecosystem C balances, but also for representing these dynamics more accurately in soil organic C and Earth system models.

Fire events in tropical peatlands often relate to dry peat conditions associated with climate variability (drought) and anthropogenic-driven ecosystem degradation. However, drought is not the only driver of long-term fire events and peatland ecosystem changes. This study used palaeoecological and geochemical proxies to investigate the long-term drivers in fire severity (FS) and the associated responses of the peatland ecosystems in Central Kalimantan, Indonesia. The results showed FS has increased from ~2300 cal. yr BP to present, and possible drivers include changes in sea level, increased frequency of El Niño events, increased biomass, and anthropogenically-driven ecosystem degradation. In response, the vegetation composition changed from a mix of peat swamp forest (PSF) and open vegetation (OV) during the late Holocene (2284 to 1129 cal. yr BP), to predominantly PSF from 1128 to 375 cal. yr BP, dry lowland mixed with swamp forest (LMS) and open vegetation (OV) from 374 to 135 cal. yr BP, and predominantly OV and freshwater swamp forest (FSF) from 134 to -62 cal. yr BP. The possible drivers of the vegetation turnover were hydrological conditions and the availability of peat nutrients, while the responses of vegetation turnover affected the accumulation and decomposition of recalcitrant organic matter in peat. The resilience of the peatland ecosystems over longer-term timeframes provided the following restoration insights: 1) PSF species (i.e. Eurya and Ilex) were resilient to high FS (charcoal influx in peat) tolerances of up to ~23 mm2cm-3yr-1 while LMS and OV species increased at lower FS threshold of ~13 mm2cm-3yr-1; 2) PSF species expanded during periods of wet conditions and high peat nutrients (i.e. TN- enriched); and 3) Future revegetation in the region can focus on tree taxa such as Euphorbiaceae, Apocynaceae plumeria, Arenga, Ficus, and Trema as they were historically able to thrive in high FS and dry hydrological conditions.