Contemporary research of lightening. Spatial and temporal distribution of lightening activity in Estonia in 2005-2008.
Sven-Erik Enno describes the frequency of lightening activity in Estonia and elsewhere – nowadays research focuses on counting lightening flashes rather than on counting thunder days. In Northern countries, lightening flashes are identified by using detectors. Since 2004, there is a detector also in Tõravere. The data derived enables to count the average number of lightning flashes per km2 per year. Although the current temporal series is too short to study the territorial distribution of flashes, some conclusions can be made. An area between Pärnu and Viljandi counties, as well as the uplands of Sakala and Otepää have somewhat more flashes that other areas. Most flashes occur between 3-5 p.m., when the ground temperature is the highest, creating favourable conditions for the development of thunderstorms.
Estonian Nature enquires
Tiit Kändler writes about the summer school of teadus.ee.
Ena Drenkhan summarizes the building of Pokumaa.
The mining of constructional resources should be better planned
Rainer Kuuba gives an overview of the audit of the National Audit Office of Estonia: it turns out that the interests of the local people and the natural environment are not taken into serious consideration and the used quarries are mostly not taken care of. In recent years, the volume of mined constructional resources has increased significantly. The audit revealed that the inspection of mining volumes is insufficient, although inspection should be carried out be three different authorities.
Horse-chestnut leaf miner: a new invasive plant pest in Estonia
Eha Švilponis, Marika Mänd and Eve Veromann warn the dendrophils against a new insect species, which carves the leaves of horse-chestnuts – one alien species weakens another. The horse-chestnut leaf miner has spread very fast all over Europe during the new millennium and it always gains immense diversity. In case of strong damage, the premature loss of leaves can be as extensive as 70-100%. Since there is no means of biocontrol, the only way to deal with the pests is to compost all leaves in autumn.
Tree of the Year: Hazelnut breeding in Estonia
Kalju Kask takes a glance at the breeding history of domestic hazelnut tree – there is only one possible candidate for a new variety as a result of decades of work. The variety was bred by Alli Süvalepp. Estonian winters are generally too harsh to breed varieties with large nuts.
Tree of the Year: Hazelnut tree, the domestic nut tree
Urmas Kokassaar looks at hazelnuts from the viewpoint of edibility: they are good, only those allergic to nuts should be careful. Nuts are rich in oils and proteins, as well as different vitamins. Most nuts weigh only 0.5 grams.
Our Amanitas 3.
Mall Vaasmaa continues her lessons about Amanitas with the help of Vello Liiv’s illustrations.
Interview: Muhu’s way could be balanced diversity
Kadri Tüür and Juhan Javoiš have interviewed Aado Keskpaik, the developmental counselor of the Muhu rural municipality and economic geographer.
Hiking trail. Puhtulaid: there is no hiking trail here and almost nothing to see.
Toomas Kukk gives directions to those wandering on the protected area and around the biology station of Puhtulaid, near Virtsu: only curious and polite visitors are welcomed here. There are several natural values on Puhtulaid, such as broad-leaved forest or park-forest, meadows, a multitude of protected plant species, ancient oak trees and pines as well as the spring and autumn migration of birds. Puhtulaid used to be an islet, but was joined with mainland in 19th-20th century as a result of land uplift. In the 19th century, there were many houses built by the local landlords, mostly by the Uexküll family. In 1939 Puhtulaid was declared as a nature protection area.
The coastal cliffs of Hiiumaa
Tapio Vares views the coastal cliffs of Hiiumaa – most of these are so well hidden that may not be found on the first attempt. Hiiumaa is located between two klint belts and is therefore quite absent of cliffs. There are some low cliffs on the surrounding islets, as well as on the few places along the shore. The author has drawn illustrations of the cliffs he discovered.
Fond of flies and butterflies
Juhani Püttsepp recalls his memories of his teacher, Professor Hans Remm on the occasion of his 80th birthday. Hans Remm was a very serious and dedicated scientist, interested in all kinds of insects. He was always prepared to catch some new flies or butterflies.
235 new species of Ceratopogonidae
Mait Talts adds the details to Hans Remm’s biography and scientific research. He described 235 new species of Ceratopogonidae in his doctoral dissertation. One of his most important activities was compiling guides for identification of different insect groups.