Search results for "habitaatti"

Do the ecological drivers of lake littoral communities match and lead to congruence between organism groups?

2020

AbstractLake littoral environments are heterogeneous, and different organisms typically show specific responses to this environmental variation. We examined local environmental and spatial factors affecting lake littoral biodiversity and the structuring of assemblages of phytoplankton, zooplankton and macroinvertebrates within and among three basins of a large lake system. We explored congruence of species composition and species richness among the studied organism groups to evaluate their general indicator potential to represent spatial variation in other groups. We expected that effects of water chemistry on plankton assemblages were stronger than effects of habitat characteristics. In co…

Effects of a mobile disturbance pattern on dynamic patch networks and metapopulation persistence

2021

Abstract Motivation Certain early-succession habitats may emerge only at restricted locations following disturbance. Therefore, whether disturbances tend to occur at certain sites or not can significantly affect habitat availability and metapopulation persistence of early-successional habitat specialists. Available models that combine metapopulation and landscape processes do not address how to model mobile, spatially shifting disturbance intensities independent of factors of site suitability. We present a model that allows the study on how a mobile disturbance pattern, of either natural or anthropogenic origin, affects patch network and metapopulation dynamics in realistic, heterogeneous l…

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 colonization–extinction dynamics of eight wood-decaying fungal species in 16 old-growth forest fragments (<14 ha) over a 20-year period (1997–2017). 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 forest–peatland 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…

Are sacred caves still safe havens for the endemic bats of Madagascar?

2018

AbstractDespite conservation discourses in Madagascar increasingly emphasizing the role of customary institutions for wildlife management, we know relatively little about their effectiveness. Here, we used semi-structured interviews with 54 adults in eight villages to investigate whether sacred caves and taboos offer conservation benefits for cave-dwelling bats in and around Tsimanampetsotsa National Park, south-west Madagascar. Although some caves were described as sites of spiritual significance for the local communities, most interviewees (c. 76%) did not recognize their present-day sacred status. Similarly, only 22% of the interviewees recognized taboos inhibiting bat hunting and consum…

From habitat use to social behavior: natural history of a voiceless poison frog, Dendrobates tinctorius

2019

AbstractDescriptive studies of natural history have always been a source of knowledge on which experimental work and scientific progress rely. Poison frogs are a well-studied group of small Neotropical frogs with diverse parental behaviors, distinct calls, and bright colors that warn predators about their toxicity; and a showcase of advances in fundamental biology through natural history observations. The dyeing poison frog, Dendrobates tinctorius, is emblematic of the Guianas region, widespread in the pet-trade, and increasingly popular in research. This species shows several unusual behaviors, such as the lack of advertisement calls and the aggregation around tree-fall gaps, which remain …

Movement of forest-dependent dung beetles through riparian buffers in Bornean oil palm plantations

2022

1. Fragmentation of tropical forests is increasing globally, with negative impacts for biodiversity. In Southeast Asia, expansion of oil palm agriculture has caused widespread deforestation, forest degradation and fragmentation. 2. Persistence of forest-dependent species within these fragmented landscapes is likely to depend on the capacity of individuals to move between forest patches. In oil palm landscapes, riparian buffers along streams and rivers are potential movement corridors, but their use by moving animals is poorly studied. 3. We examined how six dung beetle species traversed riparian buffers connected to a continuous forest reserve area within an oil palm plantation in Sabah, Ma…

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…

Muhos- ja Sanginjoki lohikalojen elinympäristöinä

2006

Semi-natural habitats in the European boreal region: Caught in the socio-ecological extinction vortex?

2022

AbstractWe propose to consider semi-natural habitats—hotspots for biodiversity—being caught in a socio-ecological extinction vortex, similar to the phenomenon described for species threatened with extinction. These habitats are essentially socioecological systems, in which socioeconomic drivers are interlinked with ecological processes. We identify four highly interlinked and mutually reinforcing socio-economic processes, pertaining to the importance of semi-natural habitats for (i) agricultural production, (ii) policy, research and development; (iii) vocational education in the fields of agricultural sciences and (iv) public’s experiences with semi-natural habitats. Evidence from six count…