Ylva Lundell

Can rehabilitation in boreal forests help recovery from exhaustion disorder? The randomised clinical trial ForRest

Modern society is faced with increasing incidence of mental and behavioural disorders. The objective of this study was to evaluate whether visits to boreal forests can be utilised for rehabilitation from exhaustion disorder (ED). This randomised controlled trial comprised of a forest rehabilitation group (n = 35) and a waiting list group (control group) (n = 43) with subsequent cognitive behavioural rehabilitation (CBR) for all participants in both groups. The recovery from ED was compared between the forest rehabilitation and the control group at baseline, after the forest rehabilitation (3 months), and at the end of the CBR (1 year). Both groups had enhanced recovery from ED after the 3-month intervention period and at the end of the CBR (1 year), and there were no significant differences between the groups in terms of psychological health measures. Mental state, attention capacity and preferences for different forest environments were studied during the forest visits. Mental state was improved, but it showed some seasonal differences. A significant effect on attention capacity was found for single forest visits, but there was no effect found for the rehabilitation period as a whole. The most popular forest environments contained easily accessible, open and bright settings with visible water and/or shelter. Forest rehabilitation did not enhance the recovery from ED compared to the control group, but the participants’ well-being was improved after single forest visits.

Soil Nutrient Availability Assessed by In Situ Ion-exchange Resin Bags as a Predictor of Growth of Swedish Coniferous Forests

Assessment of site fertility is usually based on measurements of the growth of the present stand or the composition of the field vegetation. In this study, the soil nutrient availability, assessed using in situ ion-exchange resin (IER) bags, was tested as a possible predictor of forest production. Ten Scots pine sites and five Norway spruce sites, distributed throughout Sweden, were included in the study. At the pine sites, the amounts of NO3 adsorbed by the IER correlated best to forest production ( pB 0.001), although the abundance of this ion was low. Only a weak correlation with production was found for K+ (pB 0.1). The IER adsorption of PO4 was low at the pine sites in southern Sweden.

Downslope effects of clear‐cutting in Sweden on diameter increment of picea abies and pinus sylvestris

Swedish forestry handbooks recommend that strip cutting should be practiced on forested slopes, and that uncut buffer strips should be left between clear‐cut areas and streams, because uptake by the remaining trees is believed to prevent leaching of N to the streams. We have tested this hypothesis using the assumption that, if it is true, these techniques should lead to increased diameter growth in the trees downslope of the clear‐cut because N is the growth‐limiting nutrient in Swedish mineral soils. Increment cores from trees growing downslope of 8–18‐yr‐old clear‐cuts were studied, therefore, at five sites in northern and one site in central Sweden. Growth was not influenced by the cutting at any site for the first 3 yrs, and it increased at only two of the sites thereafter. The results indicate that stands left downhill of clear‐cuts do not always act as a catch crop for leaching N.