Sökning: "northern wetlands"

Visar resultat 1 - 5 av 15 avhandlingar innehållade orden northern wetlands.

1. 1. Methane dynamics in northern wetlands: Significance of vascular plants

   Författare :Anna Joabsson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; aquatic ecology; marine biology; Hydrobiology; Växtekologi; Plant ecology; climate change; arctic wetlands; northern wetlands; plant-microbe interactions; methane emission; vascular plants; limnology; Marinbiologi; limnologi; akvatisk ekologi; Ecology; Ekologi;

   Sammanfattning : The studies presented in Papers I to VI illustrate several different aspects of the impact of vascular plants on methane emissions from northern natural wetlands. The subject has been approached on different scales, ranging from the study of microbial substrates in the vicinity of a single plant root, to an attempt to extrapolate some of the results to the entire northern hemisphere north of 50°N. LÄS MER

3. 2. Landscape hydrogeochemistry of Fe, Mn, S and trace elements (As, Co, Pb) in a boreal stream network

   Författare :Louise Björkvald; Carl-Magnus Mörth; Hjalmar Laudon; Christine Alewell; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; landscape hydrogeochemistry; boreal streams; spring flood; Fe; Mn; S; As; Co; Pb; sulphur isotopes; sulphate; organic S; DOC; spatial variability; temporal variability; wetlands; Earth sciences; Geovetenskap; geokemi; Geochemistry;

   Sammanfattning : The transport of elements by streams from headwater regions to the sea is influenced by landscape characteristics. This thesis focuses on the influence of landscape characteristics (e.g. LÄS MER

4. 3. Wetlands as a means to reduce the environmental impact of mine drainage waters

   Författare :Åsa Sjöblom; Bert Allard; Karsten Håkansson; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lakvatten; våtmarker; vattenrening; miljö; Water in nature and society; Vatten i natur och samhälle;

   Sammanfattning : In many mining regions of the world, pollution of surface water and groundwater by drainage water originating from mines aiming waste poses either a serious threat to the environment, or a severe environmental problem. During the last two and a half decades, treatment of mine drainage water in constructed and natural wetlands has emerged as an alternative to more conventional methods to handle the problem. LÄS MER

5. 4. Invading Herbivory. Effects of the Golden Apple Snail (Pomacea canaliculata) in Asian Wetlands

   Författare :Nils Carlsson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; gastropoda; invasive species; golden apple snail; herbivory; wetland functioning; biodiversity; sustainable control; indigenous predators; size-dependent competitive ability; akvatisk ekologi; limnologi; Marinbiologi; limnology; Hydrobiology; aquatic ecology; marine biology;

   Sammanfattning : The South American golden apple snail (Pomacea canaliculata) was intentionally introduced to aquacultures in South East Asia to produce snails for human consumption, but the aquatic snails soon escaped and started to consume large amounts of rice seedlings. The aim of this thesis was to quantify the effects of this invasive herbivore on aquatic plants in natural wetlands since previous research has focused on effects of the snail in rice fields. LÄS MER

7. 5. Hus och gård i Hälsingland : en studie av agrar bebyggelse och bebyggelseutveckling i norra Hälsingland Kr.f.-600 e.Kr

   Författare :Lars Liedgren; Umeå universitet; []
   Nyckelord :HUMANIORA; HUMANITIES; Roman Iron Age; Migration Period; Central Norrland; Hälsingland; sedentary; establishment of settlement; colonization; settlement expansion; farm site; house foundations; graves; house foundation terraces; building constructions; three-aisled houses; agrarian; cultivation; cereals; macro-fossil analysis; metalwork.;

   Sammanfattning : The subject of this dissertation is the sedentary agrarian settlement in northern Hälsingland and how it developed during the period AD 1-600.The study is based on a body of archaeological source material comprising archaeological remains and finds which can be linked to the sedentary agrarian economy. LÄS MER