Search results for "elinympäristö"
showing 10 items of 54 documents
Grasslands provide diverse opportunities for bird species along an urban-rural gradient
2021
Urbanisation is a major cause of biodiversity loss but careful habitat management and provision of green space within cities can help to mitigate its negative effects. Grasslands occupy large surface areas and have many functions but only a few studies have begun to explore how birds exploit these habitats in urban contexts. We hypothesized that the value of grasslands for nesting and feeding birds is likely to depend both on landscape context, and on local characteristics (grassland size, use and vegetation structure). We surveyed local habitat characteristics, breeding bird presence, abundance and foraging activity in 47 grassland sites, distributed along an urban-rural gradient in two Fr…
Wood-decaying fungi in old-growth boreal forest fragments: extinctions and colonizations over 20 years
2021
According to ecology theory, isolated habitat fragments cannot maintain populations of specialized species. Yet, empirical evidence based on monitoring of the same fragments over time is still limited. We studied the colonizationâextinction dynamics of eight wood-decaying fungal species in 16 old-growth forest fragments (<14 ha) over a 20-year period (1997â2017). We observed 19 extinctions and 5 colonizations; yet, the distribution of extinctions and colonizations did not differ from the one expected by chance for any of the species. Twenty-six percent of the extinctions took place in two natural fragments amid large forestâpeatland complexes. (Romell) Bourdot and Galzin decreased …
Characteristics, Main Impacts, and Stewardship of Natural and Artificial Freshwater Environments: Consequences for Biodiversity Conservation
2020
International audience; In this overview (introductory article to a special issue including 14 papers), we consider all main types of natural and artificial inland freshwater habitas (fwh). For each type, we identify the main biodiversity patterns and ecological features, human impacts on the system and environmental issues, and discuss ways to use this information to improve stewardship. Examples of selected key biodiversity/ecological features (habitat type): narrow endemics, sensitive (groundwater and GDEs); crenobionts, LIHRes (springs); unidirectional flow, nutrient spiraling (streams); naturally turbid, floodplains, large-bodied species (large rivers); depth-variation in benthic commu…
Densities of Atlantic salmon (Salmo salar L.) fry in relation to physical habitat, spawning redd distribution and parr abundance in a small subarctic…
2014
Two small-scale surveys were conducted in a small river to examine the effects of physical habitat characteristics, spatial spawning redd distribution and abundance of older juveniles on the Atlantic salmon (Salmo salar L.) fry (age 0+) distribution 1) shortly after the emergence and 2) after the assumed main dispersal period of fry. The effect of physical habitat variables (water depth, water velocity and substratum size), spatial spawning redd distribution and densities of older juveniles were examined using multiple linear regressions. Identical models were fitted with generalized habitat suitability indices to test their applicability to predict the variation in fry densities. Clear pat…
Spore production monitoring reveals contrasting seasonal strategies and a trade‐off between spore size and number in wood‐inhabiting fungi
2023
1. Traits related to reproduction and dispersal drive the assembly and dynamics of species communities and can explain and predict how species respond to habitat loss and fragmentation and to the changing climate. For fungi, such links remain poorly known. 2. We examine how spore production rate, a key demographic trait, is influenced by the interaction between environmental conditions and species traits. We monitored the spore production of 97 wood-inhabiting fungal species on 107 decaying logs for two years and analyzed the data with a hierarchical community model. 3. Our analysis demonstrates clear species differences in seasonal patterns, with spring and summer release dominating in per…
Adaptation and ecological speciation in seasonally varying environments at high latitudes: Drosophila virilis group
2022
Living in high latitudes and altitudes sets specific requirements on species’ ability to forecast seasonal changes and to respond to them in an appropriate way. Adaptation into diverse environmental conditions can also lead to ecological speciation through habitat isolation or by inducing changes in traits that influence assortative mating. In this review, we explain how the unique time-measuring systems of Drosophila virilis group species have enabled the species to occupy high latitudes and how the traits involved in species reproduction and survival exhibit strong linkage with latitudinally varying photoperiodic and climatic conditions. We also describe variation in reproductive barriers…
Contrasting responses of vascular plants and bryophytes to present and past connectivity in unmanaged grasslands
2022
AbstractThe area of semi-natural grasslands has decreased dramatically causing many grassland specialist species to persist in small habitat fragments. Furthermore, ecological communities once shaped by disturbances related to traditional agriculture now face the impacts of modern agriculture and urbanization. Many of the species have become endangered due to the combined effects of habitat destruction and degradation. We studied the responses of vascular plants and bryophytes to present and past connectivity in semi-natural grasslands, while accounting for the effects of local environmental conditions. We conducted vegetation surveys in 33 fragmented, unmanaged dry grasslands in Southwest …
Impact of mobility restrictions on active aging; cross-sectional associations and longitudinal changes parallel to COVID-19 restrictions
2021
Background: Meaningful activities can be done in or around home, but opportunities for participation and active aging decrease when moving in smaller areas. Active aging refers to having an active approach to life in line with one's goals, ability and opportunities. In adults over 75 years with different baseline neighborhood mobility levels, we studied active aging scores two years prior to and amid COVID-19, when governments restricted mobility of residents to slow the COVID-19 outbreak. Methods: AGNES cohort data were collected in 2017-2018 and spring 2020. Individuals were queried about their will, ability, and opportunity, and extent of doing 17 activities, and subsequently, item, comp…
Nature as a facilitator for physical activity : Defining relationships between the objective and perceived environment and physical activity among co…
2017
The aim was to study the correspondence between the objective and perceived environment and to assess their associations with physical activity (PA) in older people. 848 community-dwelling older people aged 75–90 were interviewed on their difficulties in walking 500 m, perceiving nature as a facilitator for outdoor mobility, and PA. The presence of water and landscape diversity were objectively assessed inside 500 m and 1000 m circular buffers around participants’ homes. Using logistic regression, participant data were analyzed together with the objectively assessed environmental features. Our results indicate that higher habitat diversity within natural areas correlates with higher PA amon…
The role of environmental factors for the onset of restricted mobility outside the home among older adults with osteoarthritis : a prospective cohort…
2017
Objectives The study examines how environmental factors contribute to the onset of restricted mobility outside the home among older adults with osteoarthritis. Methods This is a prospective cohort study of adults aged 50 years and older with osteoarthritis (n=1802). Logistic regression tested the association between the onset of restricted mobility outside the home and health, sociodemographic and perceived environmental barriers (hills and steep slopes, inaccessible public buildings, poor pavement condition, lack of access to public parks or sport facilities, heavy traffic or speeding cars and poor weather). The potential moderating role of environmental barriers on the association between…