Forests and forest ecosystems do not only provide goods and services but also may deliver nuisances and risks, sometimes even dangerous ones, for people visiting forests or living closet to forests. Mannerkoski (2012) noted that any forest (environmental) service, when it is maintained or produced “too much” can turn into disbenefit. It is also well-known, that what is very much appreciated by many people may be felt as disbenefit for others. This is also is true in particular for the first two cases, where the component of being “a disservice” is primarily related to related to the size of the population (European elk) or the size and/or location of the population (wolf). It is reminded, that this chapter is not a part of the CICES.
European elk (Alces alces) is the largest mammal, and most important game species in Finland (11141a) but causes also damage to forests and society. The damages are largest in pine seedling stands, which elks regard as the best nutrition nature can provide. Forests owners see it otherwise as this significantly reduce forest growth, increase regeneration costs and have an adverse impact on the quality of future trees. Silvicultural choices can even be limited in southern Finland. Ecologically, even the species structure is changing in protected areas (Heikkilä and Härkönen 2007). Outside forests moose and smaller deer cause damage for agricultural crops, and domestic animals and gardens. Most important disservices, however are the traffic accidents caused by moose, which cross the roads,
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often during dark times. These economic costs are calculated to be about 100-150 mill. € per year; considerable higher than agricultural and silvicultural damages (10-20 mill. € per year) (http://www.mmm.fi/fi/index/etusivu/kalastus_riista_porot/riist atalous/riistavahingot/hirvivahingot.html). The policy measures include regulation of elk population, state compensations for damages to forest owners and farmers (paid partially from hunting fees), traffic insurances and signs and most recently coloured plastic belts along road sides to direct elks to cross the roads in places where the risks for both parties are reduced.
Wolf. Due to the aims of the EU and national biodiversity policies the wolf (Canis lupus) is protected in Finland as in other EU countries.The size of present wolf population was estimated to be (February 2014) 140-155 individuals, and found to be growing after a decreasing trend (Finnish Game and Fisheries Institute 2014).. The problems with the wolfes are mainly local.
People leaving in primarily rural and remote areas feel insecurity for their kids, for themselves, for cattle and home animals. Threatening situations with wolves increase if the populations are growing too much or the wolfs assume intruding manners. Wolfs and their packs are sometimes also moving from place to place. European Elk is the major diet of wolf, which on its part reduce the risks discussed earlier – but also the catch of elk hunters. Hunters have also lost their dogs due to wolfs. There is a small quota for licensed hunting to keep the population limited but still viable. For many years rather heated debates around the wolf protection and the related policies have been going on, mainly between the conservationists, local people and the hunters. Policies and policy instruments are being sought to find a just balance between the different interests and perceptions. When found, the scale of the “wolf disservice” will be greatly reduced as is already practically occurred in the case of other larger mammal predators, brown bear (Ursus ursus), Lynx (Lynx lynx) and wolverine (Gulo gulo). Only bear is seen as a thread for human life (the risk cannot be entirely removed) while the wolverine in
148 particular takes a toll in reindeer herds, which however is compensated.
Snake. The only poisonous snake found in Finland is an adder (Vipera berus). The last time anyone died as a result of a bite from the adder was in 1994 but very often people are advised to have a specific medicine with them if moving in terrains where this small snake may appear.
Mosquitoes. If an ordinary Finn is asked about the inconveniences of forests, the most probable answer would be the mosquitoes, which are abundant in late summer and more abundant in the humid climate of Lapland. These are nuisances but not dangerous at all, making people to understand that sometimes there are no pleasures of hiking or picking berries in the forest without some cost. In Lapland the peak period of hiking is in September due to the bright colours of nature and the absence of mosquitoes which disappear after night frosts and are not found in windy higher elevations.
Indirect health risks carried by animals. Mostly, the Finnish forest provides safe opportunities for different kind of recreational and other activities. However, there are some other risks to be mentioned. The deer ked, or the deer louse fly (Lipoptena cervi), is a parasitic fly that came to southern Finland in the 1960s. The Finnish translation is “European elk fly”. They cause more inconvenience in the areas they are abundant, as they may go into hairs and clothes of people, may sometimes bite and cause for some people skin problems or allergy (Laukkanen et al. 2005). However, it can cause more serious health problems as the deer ked is a potential vector of various diseases, via e.g. bacteria of Bartonella spp. – as found in Central Europe (Dehio et al. 2004).
A longer known nuisance has been the sheep tick (Ixodes ricinus), which can dig into the skin of person and is not always easily taken off. In most cases it does cause anything else, but it also is potentially dangerous as being the transmitter of Lyme
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disease (borreliosis) and TBE (Tick Borne Encephalitis), and, less commonly, rabbit fever, each of which can have serious consequences for the health of those infected. Earlier, the TBE cases where found only in the southernmost archipelago of Ahvenanmaa, but now also elsewhere mainly in southern Finland. It is assumed that sheep tick in Finland is increasing as a result climate change. So far, however, only a few cases are found annually.
Hemorrhagic fever (Nefropatia epidemica) is caused by Puumala-virus (PUUV), which belongs to Hantaviruses.
Hantavirus is naturally maintained in persistently infected rodents and can be transmitted to humans via the inhalation of aerosols. In Finland it is spread by forest mole (Myodes glareolus), which is found through the whole country except the northernmost Lapland. The fever usually is high in the beginning and can include pains in the back, tiredness but also more serious side-effects. The death risk is low, 0.1 % and no permanent impacts remains. Once a person had suffered the fewer, it gives lifetime protection. It is not transmitted from human to human. The most probable risk group is the scientist investigating forest rodents (Brummer-Korvenkontio et al. 1982, Henttonen et al. 1996). Later another risk group has been found, as it has been noted that to the surest way to get molefever is chopping firewood in late autumn inside the wood storage building (Henttonen 2013).
According to Voutilainen (2013) forest habitats disturbed by intensive forest management were associated with a higher likelihood of PUUV infection in bank voles. This finding could be explained by the poorer quality of these habitats, leading to lower condition and higher susceptibility, and also by more favourable environmental conditions for virus survival outside the host. Despite the higher infection prevalence in voles, the total number of PUUV-infected bank voles was 46-64% lower in young, intensively managed than in undisturbed, old forests.
Thus, environmental change per se does not automatically lead to relative success of species that serve as reservoirs for zoonotic pathogens, and thereby, to increased human disease risk.
150 Poisonous plants and mushrooms. Approximately ten species of dangerously poisonous plants are found in Finland.
Edible plants eaten raw or wrongly processed may cause severe symptoms (Hoppu et al. 2011). Fatal intoxications by poisonous plants and mushrooms are, however, rare. Unitary deaths have been caused by lily of the valley (Convallaria majalis, cf. 32112a), Solomon’s seal (Polygonatum odoratum) and cowbane (Cicuta virosa).
None of the common berries are poisonous although red berries of brush mezereon (Daphne mezereum) look attractive but the taste is not pleasant.
Among the mushrooms, the Finnish Mycologicl Association (http://www.funga.fi/category/myrkkysienet/) lists as deadly poisonous six species: death cap (Amanita phalloides), destroying angel (Amanita virosa), ergot fungus (Claviceps purpurea), Galerina marginata and deadly webcap (Cortinarius rubellus) as well as false morel (Gyromitra esculenta). However, false morel after several parboils in abundant water is very tasty in particular as mushroom sauce or soup. In this case, the difference between ecosystem good and ecosystem bad is drawn into boiling water.
Deadly webcap has caused deaths as it can be confused with many edible mushrooms. Common roll-rim (Paxillus involutus) is an example of many other less poisonous mushrooms, which can easily be mixed with edibles species.
Pollen allergy. Alder (Alnus spp.) and birch (Betula spp.) pollens occur in south and mid- Finland in quantities capable of causing allergy symptoms. Except for birch pollen, allergenic pollens occur in far lower concentrations than in central Europe.
In northern Lapland only birch and pine pollen concentrations are high. Pollens may occur without signs of local flowering when there are southerly winds. This finding suggests that long-distance transport is an essential contributing factor to the occurrence of pollens. Pollen allergy is rather common seasonal problem among population.
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Ozone forming potential of forests. Biogenic volatile organic compounds (BVOC) emitted by terrestrial ecosystems into the atmosphere play an important role in determining atmospheric constituents including the oxidants and aerosols that control air quality and climate (Guenther 2013).
BVOCs are part of Volatile organic compounds (VOCs), which affect atmospheric chemistry and thereafter also participate in the climate change in many ways. The long-lived greenhouse gases and tropospheric ozone are the most important radiative forcing components warming the climate, while aerosols are the most important cooling component (Ruuskanen 2009).
Also VOCs can have warming effects on the climate: they participate in tropospheric ozone formation and compete for oxidants with the greenhouse gases thus, for example, lengthening the atmospheric lifetime of methane. Some VOCs, on the other hand, cool the atmosphere by taking part in the formation of aerosol particles (Ruuskanen 2009). So, VOCs of forests may not only be disservices34.
There are hundreds of BVOCs emitted into the atmosphere, but a relatively few compounds (e.g., isoprene, methanol, -pinene, acetone, and ethene) dominate the total flux. All BVOCs can influence atmospheric composition, if they are emitted at sufficient rates, but some BVOCs have a relatively high impact due to their reaction rates, products, ozone production potentials, organic aerosol yields, and other properties.
(Guenther 2013). Accurate quantitative estimates of BVOC emissions are needed to understand the processes controlling the earth system and to develop effective air quality and climate management strategies.
In Finland the biogenic VOC emissions are estimated to be almost twofold compared to the anthropogenic emissions and
34 In fact, when the volatile organic compounds are experienced by people inside the forests, they are found to lower blood pressure. It is also thought that many other health effects of staying in forests are due these compounds.
These are widely used in traditional medicine and aromatherapy in Russia, Ukraine, China and Japan (Vasara et al. 2013)
152 are dominated by monoterpenes (45% of the total annual emissions of 319 kt, i.e. 0.71 t of monoterpenes/ km2 forest land), whereas the isoprene emission is only about 7% of the total (Lindfors and Laurila 2000). It is also assumed that the increased monoterpene flux due to the damages caused by herbivory could strongly increase the total amount of monoterpenes emitted into the atmosphere. Since the predicted climate change can increase the frequency of outbreaks (e.g. caused by sawfly) there is a potential to significantly increase the herbivore-induced emission of monoterpenes (Räisänen et al. 2008).
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