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Assembly processes under severe abiotic filtering: adaptation mechanisms of weed vegetation to the gradient of soil constraints.

Nikolic N, Böcker R, Kostic-Kravljanac L, Nikolic M - PLoS ONE (2014)

Bottom Line: We analysed the multivariate response of cereal weed assemblages (including biomass and foliar analyses) to a strong man-made soil gradient (from highly calcareous to highly acidic, nutrient-poor soils) over short distances (field scale).The soil gradient favoured a substitution of calcicoles by calcifuges, and an increase in abundance of pseudometallophytes, with preferences for Atlantic climate, broad geographical distribution, hemicryptophytic life form, adapted to low-nutrient and acidic soils, with lower concentrations of Ca, and very narrow range of Cu concentrations in leaves.The trends of abundance of the different ecological groups of indicator species along the soil gradient were systematically reflected in the maintenance of leaf P concentrations, and strong homeostasis in biomass N:P ratio.

View Article: PubMed Central - PubMed

Affiliation: Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia.

ABSTRACT

Questions: Effects of soil on vegetation patterns are commonly obscured by other environmental factors; clear and general relationships are difficult to find. How would community assembly processes be affected by a substantial change in soil characteristics when all other relevant factors are held constant? In particular, can we identify some functional adaptations which would underpin such soil-induced vegetation response?

Location: Eastern Serbia: fields partially damaged by long-term and large-scale fluvial deposition of sulphidic waste from a Cu mine; subcontinental/submediterranean climate.

Methods: We analysed the multivariate response of cereal weed assemblages (including biomass and foliar analyses) to a strong man-made soil gradient (from highly calcareous to highly acidic, nutrient-poor soils) over short distances (field scale).

Results: The soil gradient favoured a substitution of calcicoles by calcifuges, and an increase in abundance of pseudometallophytes, with preferences for Atlantic climate, broad geographical distribution, hemicryptophytic life form, adapted to low-nutrient and acidic soils, with lower concentrations of Ca, and very narrow range of Cu concentrations in leaves. The trends of abundance of the different ecological groups of indicator species along the soil gradient were systematically reflected in the maintenance of leaf P concentrations, and strong homeostasis in biomass N:P ratio.

Conclusion: Using annual weed vegetation at the field scale as a fairly simple model, we demonstrated links between gradients in soil properties (pH, nutrient availability) and floristic composition that are normally encountered over large geographic distances. We showed that leaf nutrient status, in particular the maintenance of leaf P concentrations and strong homeostasis of biomass N:P ratio, underpinned a clear functional response of vegetation to mineral stress. These findings can help to understand assembly processes leading to unusual, novel combinations of species which are typically observed as a consequence of strong environmental filtering, as for instance on sites affected by industrial activities.

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Related in: MedlinePlus

Response of the major groups of weeds to the pollution-induced soil gradient.Species envelope curves along the main ordination axis after NMS ordination of untransformed (a–c) and relativized (d–f) abundances are shown. Groups are defined after Indicator Species Analysis (IV>30%, P<0.01) and subsequent classification (see Figure 2). Species indicating relatively unaltered calcareous soil (a, d); species of broad valence dominant in the middle portions of the soil gradient (b, e); species indicating most severely altered, nutrient-poor acidic soils (c, f). NMS axes are scaled in standard deviations from the centroid in a normalized configuration. Relative abundance - % of the sum of OTV values in a sample.
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pone-0114290-g005: Response of the major groups of weeds to the pollution-induced soil gradient.Species envelope curves along the main ordination axis after NMS ordination of untransformed (a–c) and relativized (d–f) abundances are shown. Groups are defined after Indicator Species Analysis (IV>30%, P<0.01) and subsequent classification (see Figure 2). Species indicating relatively unaltered calcareous soil (a, d); species of broad valence dominant in the middle portions of the soil gradient (b, e); species indicating most severely altered, nutrient-poor acidic soils (c, f). NMS axes are scaled in standard deviations from the centroid in a normalized configuration. Relative abundance - % of the sum of OTV values in a sample.

Mentions: Distinct pattern of a turnover in dominance of major weed species along the soil gradient is shown in Figure 5. Relative abundances show the trends when different competition pressure from the cereal crop is accounted for. Weeds typical for the unpolluted calcareous soils (including some rather rare, specialized calcicoles like Nigella arvensis and Myagrum perfoliatum; Figure 5a, d) were the first to disappear with increasing soil acidification by the deposited mining waste. The middle parts of the soil gradient were dominated by the common, widespread species known to have a rather broad environmental adaptations (Figure 5b, e), whereas the dominant weeds of the severely altered soils were species which did not occur on the unpolluted nearby soils of the surrounding (Figure 5c, f).


Assembly processes under severe abiotic filtering: adaptation mechanisms of weed vegetation to the gradient of soil constraints.

Nikolic N, Böcker R, Kostic-Kravljanac L, Nikolic M - PLoS ONE (2014)

Response of the major groups of weeds to the pollution-induced soil gradient.Species envelope curves along the main ordination axis after NMS ordination of untransformed (a–c) and relativized (d–f) abundances are shown. Groups are defined after Indicator Species Analysis (IV>30%, P<0.01) and subsequent classification (see Figure 2). Species indicating relatively unaltered calcareous soil (a, d); species of broad valence dominant in the middle portions of the soil gradient (b, e); species indicating most severely altered, nutrient-poor acidic soils (c, f). NMS axes are scaled in standard deviations from the centroid in a normalized configuration. Relative abundance - % of the sum of OTV values in a sample.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4256224&req=5

pone-0114290-g005: Response of the major groups of weeds to the pollution-induced soil gradient.Species envelope curves along the main ordination axis after NMS ordination of untransformed (a–c) and relativized (d–f) abundances are shown. Groups are defined after Indicator Species Analysis (IV>30%, P<0.01) and subsequent classification (see Figure 2). Species indicating relatively unaltered calcareous soil (a, d); species of broad valence dominant in the middle portions of the soil gradient (b, e); species indicating most severely altered, nutrient-poor acidic soils (c, f). NMS axes are scaled in standard deviations from the centroid in a normalized configuration. Relative abundance - % of the sum of OTV values in a sample.
Mentions: Distinct pattern of a turnover in dominance of major weed species along the soil gradient is shown in Figure 5. Relative abundances show the trends when different competition pressure from the cereal crop is accounted for. Weeds typical for the unpolluted calcareous soils (including some rather rare, specialized calcicoles like Nigella arvensis and Myagrum perfoliatum; Figure 5a, d) were the first to disappear with increasing soil acidification by the deposited mining waste. The middle parts of the soil gradient were dominated by the common, widespread species known to have a rather broad environmental adaptations (Figure 5b, e), whereas the dominant weeds of the severely altered soils were species which did not occur on the unpolluted nearby soils of the surrounding (Figure 5c, f).

Bottom Line: We analysed the multivariate response of cereal weed assemblages (including biomass and foliar analyses) to a strong man-made soil gradient (from highly calcareous to highly acidic, nutrient-poor soils) over short distances (field scale).The soil gradient favoured a substitution of calcicoles by calcifuges, and an increase in abundance of pseudometallophytes, with preferences for Atlantic climate, broad geographical distribution, hemicryptophytic life form, adapted to low-nutrient and acidic soils, with lower concentrations of Ca, and very narrow range of Cu concentrations in leaves.The trends of abundance of the different ecological groups of indicator species along the soil gradient were systematically reflected in the maintenance of leaf P concentrations, and strong homeostasis in biomass N:P ratio.

View Article: PubMed Central - PubMed

Affiliation: Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia.

ABSTRACT

Questions: Effects of soil on vegetation patterns are commonly obscured by other environmental factors; clear and general relationships are difficult to find. How would community assembly processes be affected by a substantial change in soil characteristics when all other relevant factors are held constant? In particular, can we identify some functional adaptations which would underpin such soil-induced vegetation response?

Location: Eastern Serbia: fields partially damaged by long-term and large-scale fluvial deposition of sulphidic waste from a Cu mine; subcontinental/submediterranean climate.

Methods: We analysed the multivariate response of cereal weed assemblages (including biomass and foliar analyses) to a strong man-made soil gradient (from highly calcareous to highly acidic, nutrient-poor soils) over short distances (field scale).

Results: The soil gradient favoured a substitution of calcicoles by calcifuges, and an increase in abundance of pseudometallophytes, with preferences for Atlantic climate, broad geographical distribution, hemicryptophytic life form, adapted to low-nutrient and acidic soils, with lower concentrations of Ca, and very narrow range of Cu concentrations in leaves. The trends of abundance of the different ecological groups of indicator species along the soil gradient were systematically reflected in the maintenance of leaf P concentrations, and strong homeostasis in biomass N:P ratio.

Conclusion: Using annual weed vegetation at the field scale as a fairly simple model, we demonstrated links between gradients in soil properties (pH, nutrient availability) and floristic composition that are normally encountered over large geographic distances. We showed that leaf nutrient status, in particular the maintenance of leaf P concentrations and strong homeostasis of biomass N:P ratio, underpinned a clear functional response of vegetation to mineral stress. These findings can help to understand assembly processes leading to unusual, novel combinations of species which are typically observed as a consequence of strong environmental filtering, as for instance on sites affected by industrial activities.

Show MeSH
Related in: MedlinePlus