Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes
Understory vegetation and fungi are regarded as important ecological drivers of processes like productivity and nutrient cycling in boreal forests. Whilst those processes are linked to soil water content, relatively little is known about the sources of soil water for these forest components. During...
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| Formato: | H2 |
| Lenguaje: | Inglés sueco |
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SLU/Dept. of Forest Ecology and Management
2013
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| Materias: |
| _version_ | 1855570918918586368 |
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| author | Segura, Javier |
| author_browse | Segura, Javier |
| author_facet | Segura, Javier |
| author_sort | Segura, Javier |
| collection | Epsilon Archive for Student Projects |
| description | Understory vegetation and fungi are regarded as important ecological drivers of processes like productivity and nutrient cycling in boreal forests. Whilst those processes are linked to soil water content, relatively little is known about the sources of soil water for these forest
components. During early autumn in boreal forests, temperature falls and large events of rain are frequent which may influence soil water availability. To better understand the autumn plant-soil-fungi water relationships in this ecosystem, I used stable isotopes techniques in this
study to examine the water sources for ericaceous shrubs and fungi in a Scots pine forest following a large, early autumn rain event. I hypothesize that ericaceous shrubs of two functional groups (evergreen vs. deciduous) utilize different soil water sources as a result of differences in their morphology. I also hypothesize sporocarps of saprotrophic and ectomycorrhizal fungi utilize different water sources based on previous studies that have shown a vertical separation of these fungi within the soil profile. My isotopic results showed xylem water δ18O values did not differ between evergreen and deciduous shrubs (means ranged between -9.25 and -9.98 ‰). Using a two source mixing model, it appeared that saprotrophic fungi drew 20-100 % of its water from shallow sources (organic matter -1 cm deep), whereas in general, ectomycorrhizal fungi used deeper water sources (4-75 cm deep). Moreover, rather than using water at different depths, uptake patterns and sources of water for understory vegetation and fungi appeared to be greatly influenced by a large rain event that occurred two weeks prior to sampling. This study clearly shows the importance of autumn large rain events for understory vegetation and highlights the need for further examining if the mechanisms observed are the same year to year. Therefore, more comprehensive studies integrating seasonality, soil water availability and the phenological characteristics of the plants and fungi would provide a more integrated picture of the soil water-plant-fungi continuum in the boreal forests. |
| format | H2 |
| id | RepoSLU5881 |
| institution | Swedish University of Agricultural Sciences |
| language | Inglés swe |
| publishDate | 2013 |
| publishDateSort | 2013 |
| publisher | SLU/Dept. of Forest Ecology and Management |
| publisherStr | SLU/Dept. of Forest Ecology and Management |
| record_format | eprints |
| spelling | RepoSLU58812013-07-11T14:57:49Z Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes Höstens markvattenkällor för svamp - och undervegetationen i boreala skogar : en utvärdering med stabila isotoper Segura, Javier Ericaceous shrubs fungi Pinus sylvestris rain event soil profile water stable isotopes Understory vegetation and fungi are regarded as important ecological drivers of processes like productivity and nutrient cycling in boreal forests. Whilst those processes are linked to soil water content, relatively little is known about the sources of soil water for these forest components. During early autumn in boreal forests, temperature falls and large events of rain are frequent which may influence soil water availability. To better understand the autumn plant-soil-fungi water relationships in this ecosystem, I used stable isotopes techniques in this study to examine the water sources for ericaceous shrubs and fungi in a Scots pine forest following a large, early autumn rain event. I hypothesize that ericaceous shrubs of two functional groups (evergreen vs. deciduous) utilize different soil water sources as a result of differences in their morphology. I also hypothesize sporocarps of saprotrophic and ectomycorrhizal fungi utilize different water sources based on previous studies that have shown a vertical separation of these fungi within the soil profile. My isotopic results showed xylem water δ18O values did not differ between evergreen and deciduous shrubs (means ranged between -9.25 and -9.98 ‰). Using a two source mixing model, it appeared that saprotrophic fungi drew 20-100 % of its water from shallow sources (organic matter -1 cm deep), whereas in general, ectomycorrhizal fungi used deeper water sources (4-75 cm deep). Moreover, rather than using water at different depths, uptake patterns and sources of water for understory vegetation and fungi appeared to be greatly influenced by a large rain event that occurred two weeks prior to sampling. This study clearly shows the importance of autumn large rain events for understory vegetation and highlights the need for further examining if the mechanisms observed are the same year to year. Therefore, more comprehensive studies integrating seasonality, soil water availability and the phenological characteristics of the plants and fungi would provide a more integrated picture of the soil water-plant-fungi continuum in the boreal forests. Undervegetation och svampar betraktas som viktiga, drivande ekologiska komponenter för processer som produktivitet och näringsomsättning i boreala skogar. Medan dessa processer är kopplade till markens vattenhalt, relativt lite är känt om källorna till markvatten för dessa skogskomponenter. Under början av höst en är fallande temperaturer och stora regnmängder vanliga, vilket kan påverka markvattnets tillgänglighet. För att bättre förstå höstens vattenrelationer mellan växt -jord-svamp i detta ekosystem, använde jag stabila isotops tekniker i denna studie, för att undersöka erikaceer och svampars vattenkällor i en tall skog, efter att ett stort regn inträffat under tidig höst. . En hypotes var att de två funktionella grupperna av ljungväxter (vintergröna vs lövfällande) använder olika markvattenkällor på grund av skillnader i deras morfologi. En annan hypotes var att fruktkroppar av saprotrofiska och ectomykorrhiza svampar använder olika vattenkällor, baserat på tidigare studier som har visat en vertikal separation av dessa svampar i markprofilen. Mina isotopiska resultat visade att xylem-vatten δ18O-värden inte skiljer sig mellan vintergröna och lövfällande erikaceer och varierade mellan -9,25 och -9,98 ‰. En två-käll-blandning modell visade att saprotrofiska svampar utvann 20-100% av sitt vatten från ytliga källor (organiskt material -1 cm djup), medan ectomykorrhiza svampar generellt använde djupare vattenkällor (4-75 cm djup). Istället för att använda vatten på olika djup, påverkades upptagningsmönstret och typen av vattenkällor för undervegetationen och svampar i hög grad av ett stort regnfall som inträffade två veckor före provtagningen. Denna studie visar tydligt betydelsen av stora regnfall för undervegetationens vattenupptag och understryker behovet av att ytterligare undersöka om de observerade mekanismerna är desamma år efter år. Fortsatta studier bör integrera säsongsvariationer, markvattnets tillgänglighet samt växters och svampars fenologiska egenskaper, vilket kan ge en mer samlad bild av markvatten-växt-svampar kontinuum i boreala skogar. SLU/Dept. of Forest Ecology and Management 2013 H2 eng swe https://stud.epsilon.slu.se/5881/ |
| spellingShingle | Ericaceous shrubs fungi Pinus sylvestris rain event soil profile water stable isotopes Segura, Javier Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes |
| title | Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes |
| title_full | Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes |
| title_fullStr | Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes |
| title_full_unstemmed | Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes |
| title_short | Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes |
| title_sort | autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes |
| topic | Ericaceous shrubs fungi Pinus sylvestris rain event soil profile water stable isotopes |