Search results for "forest"
showing 10 items of 3780 documents
Über die Luftwurzeln von Oleandra
1951
Über Leitbündelisolierung in achsenartigen Organen
1949
Seventy-year changes in tree species composition and tree ages in state-owned forests in Latvia
2011
Abstract During the last 100 years, forest management in Latvia has gradually become more and more focused on industrial logging, which can be expected to have affected the tree species composition and age distribution across the landscape. These changes need to be considered in forest management and conservation of biological diversity. The aim of the study was to use forest records to reconstruct the tree species composition and age distribution in the North Vidzeme Biosphere Reserve in northern Latvia for the period, 1929–1941. These data were compared to a data-set from 2008, to determine the changes that transpired during a period of intensification of forest management. The silvicultu…
Dry years and their relationship to crop production in Sri Lanka
1981
Drought is a distinct agroclimatological hazard with far reaching consequences upon crop production. Among them, famines are regarded the most serious effects of climatological drought. Although there is no doubt about the principally valid relationship between drought and production losses it seems more problematic how this relationship can be proved statistically. In this paper annual rainfall data and production figures of the three major crops of Sri Lanka, rice (paddy), tea and rubber, are correlated, but only partially a true relationship between dry years and production losses could be observed. Reason for this may be the moderate degree of annual drought. From the results shown, the…
Application of artificial neural networks and logistic regression to the prediction of forest fire danger in Galicia using MODIS data
2012
Fire danger models are a very useful tool for the prevention and extinction of forest fires. Some inputs of these models, such as vegetation status and temperature, can be obtained from remote sensing images, which offer higher spatial and temporal resolution than direct ground measures. In this paper, we focus on the Galicia region (north-west of Spain), and MODIS (Moderate Resolution Imaging Spectroradiometer) images are used to monitor vegetation status and to obtain land surface temperature as essential inputs in forest fire danger models. In this work, we tested the potential of artificial neural networks and logistic regression to estimate forest fire danger from remote sensing and f…
Evaluating fish assemblages associated with gas platforms: Evidence from a visual census technique and experimental fishing surveys
2010
Fish assemblages associated with extractive platforms were surveyed, for the first time, using traditional fishing surveys (bottom gill net) and an underwater visual census (UVC) technique in order to test the effectiveness and to identify strengths and weaknesses of both methods. The study was carried out during three seasons at two offshore gas platforms (Eleonora and Squalo C) located in the central Adriatic Sea. Both methods recorded a similar number of fish species although with only eight species in common, thus supplying complementary information and a good estimate of the total fish species richness (39) associated with these gas platforms. The use of innovative techniques, such as …
Two uncommon fungal species from Italy
2019
Mediterranean forests continue to be an inexhaustible reservoir of fungi of considerable ecological and biogeographical interest. In this paper two rare and/or infrequent species are reported. Boletopsis grisea is a threatened species in Europe while H. subtortum is infrequent.
Relevance of Broad-Leaved Forest Stands for Maintaining Epiphytic Bryophyte Species and Functional Trait Diversity in Forest Landscape in Latvia
2021
Abstract Broad-leaved trees play an important role in supporting epiphyte richness in deciduous forests. In this study we tested which broad-leaved forest stands in terms of tree composition best predicted biodiversity in regard to bryophyte species number and their functional traits. The bryoflora was surveyed in 70 stands differing in dominant broad-leaved tree species. One circular plot with diameter 30 meters was established in each stand situated in different parts of Latvia. Fifty-three of the plots were located in stands identified as protected habitats of the European Union. In total, 82 bryophyte species were recorded. At plot level the total number of species ranged between 6 and …
Persepsi Masyarakat Lokal Terhadap Pengembangan Hutan Mangrove Sebagai Kawasan Ekowisata Di Kampung Ruar Distrik Biak Timur Kabupaten Biak Numfor
2021
The mangrove forest area of Kampung Ruar, East Biak District, is an area that has traditionally been a place for fishing and lime-making efforts by the community who have been hereditary. This condition raises questions from various parties whether this location is suitable to be developed as a mangrove ecotourism destination. Development of Mangrove Ecotourism by the Papua Provincial Forestry Service as a tourist attraction by utilizing local natural potential and supporting tourism policies in Biak Numfor Regency. This study aims to see the socio-cultural conditions of local communities in the Mangrove Forest Area of Kampung Ruar, Biak Timur District, Biak Numfor Regency as an ecotour…