The Earth : climate and anthropogenic interactions in a long time perspective
(2013)- Abstract
- The Earth is a highly complex and dynamic system. Life has shaped the entire planet and evolved in response to living conditions. Ecosystems are heavily affected by climate. Rapidly changing conditions imply considerable stress on several species and ecosystems, as well as to the most dominant species on the planet.
The main focus of this thesis is to investigate climate and anthropogenic interactions with a longer time perspective, with an overall objective to learn from the past. Climate change, terrestrial carbon dynamics and biodiversity impacts are investigated, focusing on the Holocene time period.
Climatic impacts on European biodiversity are apparent, with earlier spring events at rates of... (More) - The Earth is a highly complex and dynamic system. Life has shaped the entire planet and evolved in response to living conditions. Ecosystems are heavily affected by climate. Rapidly changing conditions imply considerable stress on several species and ecosystems, as well as to the most dominant species on the planet.
The main focus of this thesis is to investigate climate and anthropogenic interactions with a longer time perspective, with an overall objective to learn from the past. Climate change, terrestrial carbon dynamics and biodiversity impacts are investigated, focusing on the Holocene time period.
Climatic impacts on European biodiversity are apparent, with earlier spring events at rates of three to five days per decade and northward range shifts by tens of kilometres per decade for several species. However, responses vary greatly between species, resulting in temporal and spatial mismatches which are major concerns for the future.
Pre-industrial human effect on terrestrial carbon cycling was investigated with a dynamic vegetation model (LPJ-GUESS). The effects of climate and atmospheric CO2 on increasing total terrestrial carbon storage were stronger than the opposite effect from land use, resulting in terrestrial carbon accumulation throughout most of the Holocene. An early substantial impact of human activities on terrestrial carbon cycling and climate is unlikely, but considerable uncertainties remain. Key uncertainties are identified: the climate effect on vegetation, the extent of human land use at temporal and spatial scale, and the land use effect on soil carbon dynamics.
A new methodology for pollen-based land use reconstructions was developed, estimating temporal and spatial extents of early anthropogenic land use in north-western Europe. The impact of past land use on terrestrial carbon storage was estimated by vegetation modelling, and for the pollen based land use scheme found to result in a carbon release of about 25% of the potential total terrestrial carbon storage.
A novel combination of ecosystem models was developed, and applied to reconstruct the Holocene range of European bison, a methodology which can be further used to improve range reconstructions and conservation planning for endangered species. (Less) - Abstract (Swedish)
- Popular Abstract in Swedish
Jorden är ett ytterst komplext och dynamiskt system. Livet har format planeten och utvecklats i takt med förändrade livsvillkor. Ekosystemen kontrolleras i hög grad av klimatet. Snabbt förändrade villkor innebär betydande påfrestningar för åtskilliga arter och ekosystem, inklusive planetens mest dominerande art, människan.
Avhandlingens huvudfokus är att undersöka samspelet mellan klimat och människan i ett långt tidsperspektiv, med det övergripande målet att lära av historien. Klimatförändringar, kolbalansen i vegetation och mark samt biologisk mångfald behandlas, med fokus på Holocen tid, dvs. sedan slutet av den senaste istiden.
Klimatförändringens... (More) - Popular Abstract in Swedish
Jorden är ett ytterst komplext och dynamiskt system. Livet har format planeten och utvecklats i takt med förändrade livsvillkor. Ekosystemen kontrolleras i hög grad av klimatet. Snabbt förändrade villkor innebär betydande påfrestningar för åtskilliga arter och ekosystem, inklusive planetens mest dominerande art, människan.
Avhandlingens huvudfokus är att undersöka samspelet mellan klimat och människan i ett långt tidsperspektiv, med det övergripande målet att lära av historien. Klimatförändringar, kolbalansen i vegetation och mark samt biologisk mångfald behandlas, med fokus på Holocen tid, dvs. sedan slutet av den senaste istiden.
Klimatförändringens inverkan på den biologiska mångfalden i Europa är redan uppenbar. Våren kommer allt tidigare för många arter, tre till fem dagar tidigare per decennium, och ett flertal arter har förflyttat sig norrut med flera mil per decennium. Men, förändringarna har varit mycket olika för olika arter, och dessa så kallade “mis-matches” kommer troligtvis bli ännu fler med fortsatta klimatförändringar.
Människans påverkan på växtlighetens och markens kolbalans under Holocen har uppskattats med en vegetationsmodell (LPJ-GUESS). Klimatet och atmosfärens ökade koldioxidhalt har enligt studien haft större positiv inverkan på denna kolbalans än utsläppen orsakade av ökad markanvändning. En slutsats är därför att människan troligen inte haft någon avgörande påverkan på klimatet eller kolbalansen under större delen av Holocen. Betydande oklarheter kvarstår dock: Klimatets effekt på vegetationen, utbredningen av mänsklighetens markanvändning i tid och rum samt jordbrukets långvariga inverkan på kolbalansen i marken.
En ny metodik har utvecklats för att med hjälp av pollenprover rekonstruera Holocen markanvändning, och med denna har den tidiga markanvändningen i nordvästra Europa rekonstruerats. Kolutsläppet orsakat av denna förindustriella markanvändning har därefter uppskattats till cirka en fjärdedel av kolet i vegetation och mark.
En ny kombination av ekosystemmodeller har utvecklats för att rekonstruera utbredningen av europeisk bison under Holocen. Metoden kan även användas för att förbättra uppskattningar av hotade arters tidigare utbredning samt bevarande. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/3732052
- author
- Olofsson, Jörgen LU
- supervisor
-
- Martin Sykes LU
- Anna Broström LU
- opponent
-
- Professor Bradshaw, Richard, University of Liverpool, Department of Geography and Planning, Liverpool, UK
- organization
- publishing date
- 2013
- type
- Thesis
- publication status
- published
- subject
- keywords
- anthropogenic, climate change, land use, biodiversity, carbon, dynamic global vegetation model, Holocene, pre-industrial, pollen, bison
- publisher
- Department of Physical Geography and Ecosystem Science, Lund University
- defense location
- Pangea auditorium, Lund
- defense date
- 2013-05-23 10:00:00
- ISBN
- 978-91-85793-35-8
- language
- English
- LU publication?
- yes
- id
- 982371da-bc54-4b41-9017-428537a0803c (old id 3732052)
- date added to LUP
- 2016-04-04 11:36:38
- date last changed
- 2020-09-23 11:55:33
@phdthesis{982371da-bc54-4b41-9017-428537a0803c,
abstract = {{The Earth is a highly complex and dynamic system. Life has shaped the entire planet and evolved in response to living conditions. Ecosystems are heavily affected by climate. Rapidly changing conditions imply considerable stress on several species and ecosystems, as well as to the most dominant species on the planet.<br/><br>
<br/><br>
The main focus of this thesis is to investigate climate and anthropogenic interactions with a longer time perspective, with an overall objective to learn from the past. Climate change, terrestrial carbon dynamics and biodiversity impacts are investigated, focusing on the Holocene time period.<br/><br>
<br/><br>
Climatic impacts on European biodiversity are apparent, with earlier spring events at rates of three to five days per decade and northward range shifts by tens of kilometres per decade for several species. However, responses vary greatly between species, resulting in temporal and spatial mismatches which are major concerns for the future.<br/><br>
<br/><br>
Pre-industrial human effect on terrestrial carbon cycling was investigated with a dynamic vegetation model (LPJ-GUESS). The effects of climate and atmospheric CO2 on increasing total terrestrial carbon storage were stronger than the opposite effect from land use, resulting in terrestrial carbon accumulation throughout most of the Holocene. An early substantial impact of human activities on terrestrial carbon cycling and climate is unlikely, but considerable uncertainties remain. Key uncertainties are identified: the climate effect on vegetation, the extent of human land use at temporal and spatial scale, and the land use effect on soil carbon dynamics.<br/><br>
<br/><br>
A new methodology for pollen-based land use reconstructions was developed, estimating temporal and spatial extents of early anthropogenic land use in north-western Europe. The impact of past land use on terrestrial carbon storage was estimated by vegetation modelling, and for the pollen based land use scheme found to result in a carbon release of about 25% of the potential total terrestrial carbon storage.<br/><br>
<br/><br>
A novel combination of ecosystem models was developed, and applied to reconstruct the Holocene range of European bison, a methodology which can be further used to improve range reconstructions and conservation planning for endangered species.}},
author = {{Olofsson, Jörgen}},
isbn = {{978-91-85793-35-8}},
keywords = {{anthropogenic; climate change; land use; biodiversity; carbon; dynamic global vegetation model; Holocene; pre-industrial; pollen; bison}},
language = {{eng}},
publisher = {{Department of Physical Geography and Ecosystem Science, Lund University}},
school = {{Lund University}},
title = {{The Earth : climate and anthropogenic interactions in a long time perspective}},
year = {{2013}},
}