Sökning: "woody vegetation"

Visar resultat 6 - 10 av 18 avhandlingar innehållade orden woody vegetation.

1. 6. Megaherbivores and Earth system functioning: Landscape-scale effects of white rhino loss on vegetation, fire and soil carbon dynamics

   Författare :Olli Hyvärinen; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Megaherbivores (> 1000 kg) have been suggested to strongly influence ecosystem functioning with consequences potentially scaling up to the global climate. However, due to poaching, we may lose some of the most vulnerable species at functional densities in the wild in the coming decades. LÄS MER

3. 7. Linking Landscapes and Livelihoods : Ecosystem services as a lens in Sudano-Sahelian West Africa

   Författare :Hanna Sinare; Line Gordon; Anders Malmer; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ecosystem services; landscapes; livelihoods; agroforestry; Sudano-Sahel; West Africa; Natural Resources Management; naturresurshushållning;

   Sammanfattning : Integrated landscape approaches are increasingly called for to reconcile multiple objectives from the perspectives of agriculture, forestry, poverty alleviation and biodiversity conservation. Sudano-Sahelian West Africa with low agricultural productivity and widespread poverty is a hotspot for these issues and has attracted international interest in interventions to improve livelihoods. LÄS MER

4. 8. Small biotopes: Landscape and management effects on pollinators

   Författare :Annika Söderman; Biodiversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Agri-environmnetal scheme; management; agriculture; landscape complexity; heterogeneity; landscape scale; mall biotopes; field boundaries; pollinating insects; pollination; bumblebees; solitary bees; hoverflies;

   Sammanfattning : The intensification of agriculture during the second half of the twentieth century, has caused sever declines of farmland biodiversity, where loss of semi-natural habitats is one of the major drivers. To halt further loss of habitat and biodiversity, agri-environmental schemes (AES) are used to compensate farmers to use methods less harmful to the environment. LÄS MER

5. 9. Bush Encroachment and the Role of Browse in Cattle Production : An ecological perspective from a bush encroached grazing system, Olifants Drift, Kgatleng District, Southeast Botswana

   Författare :Nkobi Moleele; Norman Owen-Smith; Stockholms universitet; []
   Nyckelord :savannas; bush encroachment; carrying capacity; browse; biomass; range degradation; colour infrared photographs; Landsat Thematic Mapper; mid infrared bands; tannins; toxins; aromatic substances; Dicrostachys cinerea; Grewia flava; NDVI; Olifants Drift; Botswana; naturgeografi; Physical Geography;

   Sammanfattning : The increase in density and cover of woody plant species is coincident with the introduction of cattle in southern Africa, and it is a wide spread phenomenon in the savannas of the world. The causes are little understood, but can only be speculated to be either anthropogenic or natural or a combination of both. LÄS MER

7. 10. The Role of Carbon-Nitrogen Interactions for Terrestrial Ecosystem Dynamics under Global Change - a modelling perspective

   Författare :David Wårlind; Institutionen för naturgeografi och ekosystemvetenskap; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; C-N Interactions; Ecosystem Modelling; DGVM; Nitrogen; Carbon; Climate Change;

   Sammanfattning : The nature of future climate change will depend on anthropogenic emissions of CO2, as well as climate- and CO2-mediated feedbacks through carbon (C) cycling in both terrestrial ecosystems and oceans. Terrestrial ecosystems remove presently about 25% of the anthropogenic CO2 fossil-fuel and land-use change emissions, but to attribute which mechanisms cause this uptake, and the key regions where it occurs, is a challenging task. LÄS MER