Hopp til hovedinnholdet

Publikasjoner

NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.

2018

Til dokument

Sammendrag

Soil macroporosity affects field-scale water-cycle processes, such as infiltration, nutrient transport and runoff1,2, that are important for the development of successful global strategies that address challenges of food security, water scarcity, human health and loss of biodiversity3. Macropores—large pores that freely drain water under the influence of gravity—often represent less than 1 per cent of the soil volume, but can contribute more than 70 per cent of the total soil water infiltration4, which greatly magnifies their influence on the regional and global water cycle. Although climate influences the development of macropores through soil-forming processes, the extent and rate of such development and its effect on the water cycle are currently unknown. Here we show that drier climates induce the formation of greater soil macroporosity than do more humid ones, and that such climate-induced changes occur over shorter timescales than have previously been considered—probably years to decades. Furthermore, we find that changes in the effective porosity, a proxy for macroporosity, predicted from mean annual precipitation at the end of the century would result in changes in saturated soil hydraulic conductivity ranging from −55 to 34 per cent for five physiographic regions in the USA. Our results indicate that soil macroporosity may be altered rapidly in response to climate change and that associated continental-scale changes in soil hydraulic properties may set up unexplored feedbacks between climate and the land surface and thus intensify the water cycle.

Til dokument

Sammendrag

Phytometers are indicator transplants that provide information on site conditions based on plant survival,growth and reproduction. Since this is a relatively new approach, standards for its implementation remain to bedefined, for example, during peatland restoration. Peatland restoration frequently aims at recovering char-acteristic communities, and a key attribute of successfully restored ecosystems is their capacity to sustain viablepopulations of target species. When not actively introduced, these species are expected to establish on their ownafter improving site conditions, for example by rewetting. Assessments to determine whether this goal is metrequire the long-term monitoring of species’ presence, whereas the underlying causes of these observations, i.e.site or dispersal limitation, often remain unknown. Using phytometers within ecological restoration helps ad-dressing this question. The goal of this study is to compare the responses of several species and traits to en-vironmental conditions in restored peatlands. Three target species (Drosera rotundifolia, Eriophorum vaginatum,Vaccinium oxycoccos) were planted in restored montane peatlands in central Germany, while in a greenhouseexperiment, the same species were grown on peat from the field sites and exposed to two water levels. Severalplant traits were measured and compared with variation in light, water and soil conditions. The response tohabitat conditions was species-specific, indicating that the use of different phytometers increases the reliabilityof monitoring. Survival and growth traits were suitable to assess a wide range of abiotic conditions, whiledifferences in reproductive output were more time-consuming to measure. Survival provided the most conclusiveresults for species sensitive to stressful habitat conditions. Biomass and other size metrics of the phytometers, aswell as growth and reproductive traits were partly redundant. Thus, we suggest recording survival and biomassand use non-destructive growth measurements for repeated assessments, while the choice of the most suitablesize trait should depend on the growth form. Our study stresses the potential of phytometers for monitoring therestoration outcome, while highlighting the importance of species and trait selection.

Til dokument

Sammendrag

Persistence of restored populations depends on growth, reproduction, dispersal, local adaptation, and a suitable landscape pattern to foster metapopulation dynamics. Although the negative effects of habitat fragmentation on plant population dynamics are well understood, particularly in grasslands, the population traits that control grassland restoration are less known. We reviewed the use of population traits for evaluating grassland restoration success based on 141 publications (1986–2015). The results demonstrated that population demography was relatively well‐assessed but detailed studies providing information on key stages of the life cycle were lacking despite their importance in determining population viability. Vegetative and generative performances have been thoroughly investigated, notably the components of plant fitness, such as reproductive output, while genetic and spatial population structures were largely ignored. More work on the population effects of ecological restoration would be welcomed, particularly with a focus on population genetics. Targeted species were principally common and dominant natives, or invasive plants while rare or threatened species were poorly considered. Evaluation of ecological restoration should be conducted at different scales of ecological complexity, but so far, communities and ecosystems are over represented, and more focus should be directed towards a population approach as population traits are essential indicators of restoration success.