Can a plant cause more harm than good in an ecosystem? The beautiful crowberry makes green, carpeted heath and tasty berries, and it stores carbon. But for many species in the ecosystem, it is a poor collaborator. The leaves of crowberry contain substances that can prevent other plant species from germinating and growing, and a number of soil organisms give up in the presence of crowberry. Grazing animals avoid crowberry-dominated areas. Crowberry also affect freshwater systems. Fry can be harmed when in rivers where crowberry is abundant along the riverbanks. Hence, when crowberry now seems to benefit from climate change and increases in abundance, the ecosystem consequences can be severe.
In MONEC we are documenting how much, and in which habitats, crowberry has changed its distribution over the last two to five decades. With this information we will anticipate where, and at what rate, crowberry will encroach in the future. Next we are testing actions that both limit crowberry and promote local biodiversity and primary production. Biodiversity and primary production are ecosystem services that are not directly harvestable by us. By nevertheless including these services into economic models we can test if actions that limit crowberry and promote biodiversity, also prove to be economically viable. The testing is in collaboration with reindeer herders and sheep farmers in their pastures in Northern Norway. Finally, we will assess if, in the long term, there is ecological and economical benefit from limiting crowberry, or if the ecosystem services that crowberry deliver outperforms its disservices.
In this project we will challenge the current management model of the socio-ecological system of reindeer husbandry by evaluating management effects of crowberry, a native invasive species. The system is currently managed in terms of animal numbers. Moreover, because reindeer husbandry shares pastures with sheep husbandry and a range of wildlife species, a potential failing management to what seems to be a decreasing carrying capacity of the rangeland pastures, can have serious ecosystem ramifications.
Crowberry has ecological ramifications to the biodiversity terrestrial ecosystem and likely also the connected freshwater ecosystem, in turn likely impacting on the socio-ecological system as well as more general ecosystem functioning to the extent it can be considered an ecosystem disservice. However, managing a native invasive species may seem like an impossible task. In this project we evaluate the costs and benefits of management of crowberry to the socio-ecological system as well as to other ecosystem services.
As our evaluation system we will combine a set of approaches including revisiting large scale areas to assess the impact of the above mentioned pressures over the last decades. We will focus on biodiversity and ecosystem functioning of the terrestrial ecosystem, and assess associated ecosystem services of both the terrestrial and the connected freshwater systems. We will explore ways to value biodiversity and ecosystem functioning as input to bio-economic modelling. Finally, we will provide a policy-relevant cost-benefit analysis of consequences of multiple pressure management, exploring whether management of the ecosystem disservices of a native invasive plant is advisable.