The effect of anthropogenic disturbance on soil fungal communities
Failid
Kuupäev
2024-07-15
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Abstrakt
Käesolev doktoritöö uurib, kuidas inimtekkelised häiringud nagu näiteks võõrtaimede lisandumine looduslikesse kooslustesse, põllumajanduses kasutatavad mürkained ning künd mõjutavad mullaseente kooslusi. Kuna mullaseened mõjutavad otseselt taimede kasvu ning osalevad toitaineteringes, siis on neil võtmeroll ökosüsteemi funktsioonide säilitamisel ning on ülioluline hinnata, kuidas mullaseente kooslused inimmõju tagajärjel muutuvad. Antud doktoritöö tulemused näitavad, et võõrtaimede lisandumine looduslikesse koolsustesse ei toonud kaasa olulist muutust mullaseente liigirikkuses ning mitmekesisuses. Samas võimaldas võõrtaimede ning kohalike taimede tunnuste erinevust arvestav mõõdik tuvastada mullaseente koosluse koosseisus toimunud muutusi, mis võivad aja jooksul suureneda. Keemiliste häiringute mõju sõltub väga tugevalt häiringust, nii näiteks mineraalne väetis ning pestitsiidide kasutamine on mullaseentele pärssiva, samas kui orgaanilise väetise kasutamine hoopis soodustava mõjuga. Mitme keemilise häiringu samaaegsel esinemisel on neil suurem negatiivne mõju samas kui mehhaanilise häiringu esinemine võib keemilise häiringu, näiteks pestitsiidi, negatiivset mõju hoopis leevendada. Need tulemused viitavad sellele, et mitme samaaegse häiringu mõju on raskesti ennustatav ning vajab veel uurimist. Samas näitasid antud doktoritöö tulemused, et mullaseente, täpsemalt taimedega vastastikku kasulikus kooselus elevate krohmseente olemasolu soodustab taimkatte taastumist pärast väikeseskaalalist häiringut. Seega on krohmseentel oluline roll liigirikka ning produktiivse taimkatte säilitamisel. Parem teadmine sellest, kuidas inimtegevus mullaseente kooslusi mõjutab on oluline selleks, et üha suureneva inimmõju juures ökosüsteeme paremini säilitada ning taastada.
This doctoral thesis extends our understanding of how soil fungal communities respond to disturbances caused by human activities, which have led to the degradation of local biodiversity and disruption of ecosystem services. Soil fungi play a crucial role in sustaining ecosystem functions, so understanding the impact of anthropogenic disturbances on soil fungal communities is essential for fully grasping the consequences of human activities for ecosystems. This thesis found that non-native plant invasion, the most common biotic disturbance resulting from international trade, had little impact on the soil fungal community. Minor variation in soil fungal communities could be detected in relation to morphological dissimilarity between native and non-native plants, but not in relation to non-native plant abundance. In addition, common chemical abiotic disturbances, such as mineral and organic fertilizer application, have effects ranging from negative to positive on soil fungal diversity. However, mechanical disturbances such as tillage, showed no strong influence on soil fungal diversity. Interestingly, the results suggest that the combination of two chemical disturbances, such as mineral fertilizer and pesticide application, can amplify their negative effects on soil fungi, while mechanical disturbance can alleviate the negative effect of herbicide addition. This indicates that the combined effects of multiple disturbances is not simply the addition of single-factor effects, and further studies are needed as anthropogenic disturbances commonly occur simultaneously in real life. Moreover, with the intensification of human activities, small-scale disturbances in natural or semi-natural habitats have increased significantly but have received very little attention. This thesis shows that suppression of soil fungi decreases the diversity and biomass of re-established vegetation after small-scale disturbance, highlighting the importance of soil fungi in the self-recovery of plant communities following disturbance. In conclusion, soil fungi exhibit complex responses to multiple disturbances and play a crucial role in vegetation recovery. Further studies should investigate the effects of multiple disturbances on soil fungi, while considering their key role in vegetation recovery.
This doctoral thesis extends our understanding of how soil fungal communities respond to disturbances caused by human activities, which have led to the degradation of local biodiversity and disruption of ecosystem services. Soil fungi play a crucial role in sustaining ecosystem functions, so understanding the impact of anthropogenic disturbances on soil fungal communities is essential for fully grasping the consequences of human activities for ecosystems. This thesis found that non-native plant invasion, the most common biotic disturbance resulting from international trade, had little impact on the soil fungal community. Minor variation in soil fungal communities could be detected in relation to morphological dissimilarity between native and non-native plants, but not in relation to non-native plant abundance. In addition, common chemical abiotic disturbances, such as mineral and organic fertilizer application, have effects ranging from negative to positive on soil fungal diversity. However, mechanical disturbances such as tillage, showed no strong influence on soil fungal diversity. Interestingly, the results suggest that the combination of two chemical disturbances, such as mineral fertilizer and pesticide application, can amplify their negative effects on soil fungi, while mechanical disturbance can alleviate the negative effect of herbicide addition. This indicates that the combined effects of multiple disturbances is not simply the addition of single-factor effects, and further studies are needed as anthropogenic disturbances commonly occur simultaneously in real life. Moreover, with the intensification of human activities, small-scale disturbances in natural or semi-natural habitats have increased significantly but have received very little attention. This thesis shows that suppression of soil fungi decreases the diversity and biomass of re-established vegetation after small-scale disturbance, highlighting the importance of soil fungi in the self-recovery of plant communities following disturbance. In conclusion, soil fungi exhibit complex responses to multiple disturbances and play a crucial role in vegetation recovery. Further studies should investigate the effects of multiple disturbances on soil fungi, while considering their key role in vegetation recovery.
Kirjeldus
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