Browsing by Subject "kaupunkimetsät"

Luontopohjaiset ratkaisut (NBS, Nature-based solutions) ovat tietoisesti suunniteltuja ratkaisuja komplekseihin haasteisiin, ja niiden ytimessä ovat ”luonnon” elementit, kuten valikoidut mikrobit ja kasvillisuus. Nämä elementit ovat luontopohjaisen ratkaisun ytimessä, ja näin tekevät NBS:stä usein ekologisesti kestävämmän vaihtoehdon perinteisille teknisille maisemaratkaisuille. Suuri osa olemassaolevasta kirjallisuudesta on siten keskittynyt NBS:n ekologiseen ulottuvuuteen huolimatta niiden sisäsyntyisestä moniulotteisuudesta. Sosiaaliset elementit ovat kuitenkin paitsi olennainen osa NBS:n suunnittelua ja toimintaa, myös niiden pitkän tähtäimen onnistumisen edellytys. Aiempi tutkimus on osoittanut, että luontopohjaisten ratkaisujen menestys riippuu ennen kaikkea niiden paikallisen yhteisön saavuttamasta yhteydestä ja omistajuudesta. Näiden suhteiden muodostuminen tapahtuu usealla tasolla, mukaan lukien psykologisella ja asuinaluetasolla. Siksi tämä tutkimus tarkastelee luontopohjaisiin ratkaisuihin yhdistettäviä merkityksiä ja näkemyksiä paikallisen, karttapohjaisen, audio-visuaalisen kyselyn kautta. Vastauksista nousee esiin kaksi primääristä huomiota: Ensiksi, aineistosta on mahdollista erottaa NBS- ja äänimaailmamieltymysten, sekä avointen paikan merkitysten pohdintojen kautta vähintään kaksi paikallista arkkityyppiä, jotka lähestyvät luontopohjaisia ratkaisuja uniikeilla tavoilla. Toiseksi, erot näiden arkkityyppien reaktioissa paikallisiin luontopohjaisiin ratkaisuihinsa voivat selittyä osin luontosuhteen ja paikallishistorian kautta. Nämä löydöt korostavat yhtäältä olemassaolevan henkilökohtaiseen psykologiseen ulottuvuuteen keskittyvän NBS-tutkimuksen merkitystä, ja toisaalta paikallisen ja yhteisötason ymmärrystä kokonaisen

Woodlands are a significant part of the Finnish nature and especially in cities an important source of wellbeing of the citizens. Urban woodlands are entities shaped by natural dynamics and intensive recreational pressure. As the population of the Earth is urbanizing and urban areas cover constantly increasing proportion of the Earths surface the meaning of urban nature is getting more important. Intensive recreational use, especially outside established routes, is posing a threat on the regeneration of the urban woodlands in Helsinki region. Intensive recreational use has been shown to be associated with the depletion of urban woodlands and the deterioration of regenerative capacity. Recreation in urban forests is important for the city dwellers, and a strong restriction on recreational use is not meaningful. The areas favorable to renewal can be created and protected by focusing the wear of the forest floor by controlling the passage of forest users. Natural barriers, such as downed logs, are a suitable solution for controlling the passage of forest users because of their aesthetic and ecological benefits. However, the most important thing is to figure out how they function as the drivers of the passage of forest users, which was explored in this study. In 1998, 18 experimental plots were established in worn urban woodland parcels in Helsinki region to investigate whether downed logs could be useful in limiting the passage and wear of the forest floor and thereby supporting sapling establishment. The plots were rectangular in shape and 225-550 m² in size. After the first data collection, in 1998, the treatments were conducted; in the log treatment, a tree was downed into the plot, in the gap treatment the downed tree was taken out of the plot to create a just a hole in the canopy. Gap treatment functioned as a procedural control. There were six experimental plots for each treatment, plus six control plots. Data from the experimental plots was collected in 1998 prior to the treatment, and again in 2000 and 2010 after the treatments. The map data was converted to digital format using GIS (ArcMap) and edited in Microsoft Excel to be analyzed in Rstudio. The results of the study give an indication that downed logs can be functional in supporting the regeneration of urban woodlands. The intensity of the seedlings on the experimental plots was highest in the immediate vicinity of the downed logs. The spatial distribution of seedlings on the experimental plots was most influenced by the wear class (on a scale of 0-4), so that in the wear class 0 the seedling intensity was the highest and in wear classes 3 and 4 the lowest. On the basis of this study, downed logs can be expected to have an indirect positive effect on the occurrence of seedlings through the addition of unworn forest floor. The statistical models used in the study showed that downed logs had an effect on the sapling material of the experimental plots, but failed to fully describe the studied phenomenon. As a result of the development of statistical models, we will hopefully receive more detailed information on the significance of downed logs for the regeneration of worn urban woodlands in the near future.