Search results for "WATERS"
showing 10 items of 281 documents
Ojituksen ja ennallistamisen aiheuttamat muutokset kasvilajistossa ja –yhteisöissä
2013
Verkostonäkökulma ennallistamiskohteiden valinnassa
2013
Verkostonäkökulma korostuu vahvasti luonnonsuojelun suunnittelussa Suomessa ja maailmalla. Suojelualueita ei voi nähdä yksittäisinä eristyneinä alueina, vaan luonnonsuojelualueiden verkosto ja koko ympäröivä maisema ylläpitävät yhdessä tietyn alueen eliölajistoa. Parhaiden alueiden kytkeytyvyyden varmistamista ja verkostojen ylläpitämistä on myös ehdotettu ratkaisuksi biodiversiteetin säilyttämiselle, kun ilmastonmuutos pakottaa lajeja siirtymään uusille asuinalueille. Verkostonäkökulma kannattaa huomioida myös ennallistamiskohteiden valinnassa – mikä ei kuitenkaan ole yksiselitteistä ja helppoa. nonPeerReviewed
Ekosysteemin ennallistamisen ja luonnonhoidon ekologia
2013
The Inland Water Copepod Fauna of a Traditional Rural Landscape in a Mediterranean Island (Crustacea, Copepoda)
2022
Although the Mediterranean area is a well-known hotspot of biological diversity, the crustacean assemblages inhabiting inland waters of the Mediterranean islands are to date unevenly known, and detailed information is missing for most taxa and areas. In the frame of this paper, we provide a checklist and a characterization of the copepod fauna of the lentic water bodies occurring in a traditional rural landscape of Sicily, where the co-existence of agriculture, woodlands, and pastoral activities lead to the presence of a wide range of different aquatic habitats. Overall, 22 copepod species belonging to the orders Calanoida, Cyclopoida, and Harpacticoida have been found in the 92 surveyed si…
Aquatic Macrophytes Occurrence in Mediterranean Farm Ponds: Preliminary Investigations in North-Western Sicily (Italy)
2021
Mediterranean wetlands are severely affected by habitat degradation and related loss of biodiversity. In this scenario, the wide number of artificial farm ponds can play a significant role in the biodiversity conservation of aquatic flora. In the present contribution we show the preliminary results of a study on Mediterranean farm ponds of north-western Sicily (Italy), aimed to investigating the environmental factors linked to the occurrence of submerged macrophytes (vascular plants and charophytes). We studied the aquatic flora of 30 ponds and determined the chemical and isotopic composition of their water bodies on a subset of the most representative 10 sites. Results show that (1) farm p…
Dangerous relationships : biases in freshwater bioassessment based on observed to expected ratios
2018
Copyright by the Ecological Society of America The ecological assessment of freshwaters is currently primarily based on biological communities and the reference condition approach (RCA). In the RCA, the communities in streams and lakes disturbed by humans are compared with communities in reference conditions with no or minimal anthropogenic influence. The currently favored rationale is using selected community metrics for which the expected values (E) for each site are typically estimated from environmental variables using a predictive model based on the reference data. The proportional differences between the observed values (O) and E are then derived, and the decision rules for status ass…
Desafíos y oportunidades de Sentinel-2 en la monitorización de las aguas continentales
2023
En los ecosistemas de agua dulce, la escasez y la contaminación de este recurso está promoviendo que los organismos gubernamentales incluyan en sus agendas estrategias para mitigar esta situación a través de una gestión sostenible. La Directiva Marco del Agua establece entre sus requerimientos la monitorización del estado ecológico de las aguas continentales para determinar su calidad. Las imágenes satelitales ofrecen una visión sinóptica y continua a partir de la que es posible derivar métricas del estado ecológico. Esas métricas son un complemento a los tradicionales muestreos ya que se incrementa la cobertura espacial y la periodicidad en la monitorización. Sentinel-2, con su sensor Mult…
Comparing the monitoring and evaluation systems of watershed management related development projects in Amhara, Ethiopia
2012
Natural resource degradation is both a cause and a result of poverty in Ethiopia. Therefore it is important to include watershed management into efforts to reduce poverty and food insecurity in the country. In order to see if different interventions are effective in restoring the degraded environment, it is important to have a functioning monitoring and evaluation system that includes natural resource degradation and other environmental factors. This study compares the monitoring and evaluation systems used by five different projects involved in watershed management in the Amhara region, Ethiopia. The objective is to find out whether these systems are providing adequate and scientifically v…
VARIABILITY OF REMOTE SENSING SPECTRAL INDICES IN BOREAL LAKE BASINS
2018
Remotely sensed hyperspectral data has widely been used to determine water quality parameters in oceanic waters. However in freshwater basins the dependence between the hyperspectral data and the parameters is more complicated. In this work some ideas are presented concerning the study of this dependence. The data used in this study were collected from the lake Hiidenvesi in southern Finland. The hyperspectral data consists of reflectances in 36 bands in the wavelength area 508…878 nm and the separately measured water quality parameters are turbidity, blue-green algae, chlorophyll, pH and dissolved oxygen. Hyperspectral data was used as bare band reflectances, but also in the …
What makes segmentation good? A case study in boreal forest habitat mapping
2013
Segmentation goodness evaluation is a set of approaches meant for deciding which segmentation is good. In this study, we tested different supervised segmentation evaluation measures and visual interpretation in the case of boreal forest habitat mapping in Southern Finland. The data used were WorldView-2 satellite imagery, a lidar digital elevation model (DEM), and a canopy height model (CHM) in 2 m resolution. The segmentation methods tested were the fractal net evolution approach (FNEA) and IDRISI watershed segmentation. Overall, 252 different segmentation methods, layers, and parameter combinations were tested. We also used eight different habitat delineations as reference polygons agains…