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Accueil du site → Doctorat → Chine → 2010 → Effects of Vegetation Restoration on Soil Quality and Plant Physio-ecological Adaptability in Water-wind Erosion Region

Graduate School,Chinese Academy of Sciences (2010)

Effects of Vegetation Restoration on Soil Quality and Plant Physio-ecological Adaptability in Water-wind Erosion Region

白文娟; Bai Wen Juan

Titre : Effects of Vegetation Restoration on Soil Quality and Plant Physio-ecological Adaptability in Water-wind Erosion Region

Auteur : 白文娟; Bai Wen Juan

Grade : Doctoral Dissertation 2010

Université : Graduate School,Chinese Academy of Sciences

Résumé partiel
Ecological environment is fragile in water-wind erosion region where soil erosion is very serious. And this region is the main source of the coarse sediments of the Yellow River. Sound vegetation restoration measures are of importance to the vegetation restoration of degraded ecosystem in the study area. Vegetation-soil systems in different habitats were studied using the field survey and laboratory experiment. In detail, characteristics of standing vegetation and soil seed bank during vegetation restoration were identified. The effects of vegetation restoration on soil quality and water and photosynthesis physio-ecological adaptability were clarified. These results are helpful to reveal the interactional mechanism between vegetation and soil quality and provide theoretical basis for vegetation restoration and reconstruction in water-wind erosion region on the Loess Plateau. The main conclusions are as follows :(1) Species composition and species diversity of communities during vegetation restoration were clarified. Standing vegetation was dominated by Compositae, Gramineae and Leguminocae species, which accounted for 76% of total species numbers. For life forms, perennial hebaceous plants were dominant, which occupied 64% of total species numbers. Vegetation succession process was classified three stages.The dominant species were annuals of Artemisia scoparia and Salsola ruthenica in the.first stage ; Astragalus melitoloides in the second stage ; Stipa bungeana in the three stages (after 15a). And the role of Stipa bungeana as constructive species remanined unchanged with vegetation succession after 15a. There was no obvious tendency in richness index. Shannon-wiener and evenness index increased, while ecological dominance declined with increased years. The results indicated that species composition of community becomed even and stable along with vegetation succession. (2) Characteristic of soil seed bank and its effect on vegetation restoration were studied. The results showed that density of soil seed bank ranged from 105 to 6 301 seeds m-2 with an average of 2 095±448 seeds m-2. Soil seed bank had vertical distribution pattern that seed density at 0-5 cm depth (accounting for 72%) was greater than that at 5-10 cm depth. The seed bank was mainly composed of early successional species such as Artemisia scoparia and Eragrostis pilosa and their dentities accounted for 72% of total density (41.37% and 20.81%, respectively). Species of the later successional stages (i.e. target species) were absent. Similarity between seed bank and standing vegetation was low in the whole. Their Sorensen similarity coefficient ranges from 0 to 0.667. The tendency of diversity with increased years was consistent with the standing vegetation. The results suggested that seed bank plays an important role on vegetation in the early succession stage, while contributes little in the later succession stages. Potential for vegetation restoration from soil seed banks is limited and it is recommended to employ morderate human intervention to accelerate succession.(3) Impact of vegetation succession of abandoned croplands on soil quality was clarified.The results showed that content of >0.25 mm soil water stable aggregate and MWD increased, while destruction rate of >0.25 mm soil water stable aggregate decreased with increased years, suggesting that soil structure stability increase during vegetation restoration

Mots clés : Water-wind erosion region on the Loess Plateau; Vegetation restoration; Soil seed bank; Soil quality; Water physio-ecology; Photosynthesis physio-ecology;

Présentation (CNKI)

Page publiée le 5 mai 2013, mise à jour le 2 mai 2018