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Background. The glaciers in the Alps, as in other high mountain ranges and boreal zones, are generally retreating and leaving a wide surface of bare ground free from ice cover. This early stage soil is then colonized by microbes and vegetation in a process of primary succession. It is rarely experimentally examined whether this colonization process is linear or not at the ecosystem scale. Thus, to improve our understanding of the variables involved in the carbon accumulation in the different stages of primary succession, we conducted this research in three transects on the Matsch glacier forefield (Alps, N Italy) at an altitude between 2350 and 2800 m a.s.l. Methods. In three field campaigns (July, August and September 2014) a closed transparent chamber was used to quantify the net ecosystem exchange (NEE) between the natural vegetation and the atmosphere. On the five plots established in each of the three transects, shading nets were used to determine ecosystem response function to variable light conditions. Ecosystem respiration (Reco) and gross ecosystem exchange (GEE) was partitioned from NEE. Following the final flux measurements, biometric sampling was conducted to establish soil carbon (C) and nitrogen (N) content and the biomass components for each transect. Results. A clear difference was found between the earlier and the later successional stage. The older successional stages in the lower altitudes acted as a stronger C sink, where NEE, GEE, and Reco were significantly higher than in the earlier successional stage. Of the two lower transects, the sink capacity of intermediate-succession plots exceeded that of the plots of older formation, in spite of the more developed soil. Total biomass (above- and belowground) approached its maximum value in the intermediate ecosystem. Whilst, the later stage of succession predominated in the corresponding belowground organic mass (biomass, N and C). Outlook. We found that the process of carbon accumulation along a glacier retreat chronosequence is not linear, and after a quite rapid increase in carbon accumulation capacity in the first 150 years, in average 9 g C m-2 y-1, it slows down, taking place mainly in the belowground biomass components. Concurrently, the photosynthetic capacity peaks in the intermediate stage of ecosystem development. If confirmed by further studies on a larger scale, this study would provide evidence for a predominant effect of plant physiology over soil physical characteristics in the green-up phase after glacier retreat, which has to be taken into account in the creation of scenarios related to climate change and future land use.

Considering ecosystem disservices (EDS) of urban forests alongside the services (ES) can lead to better-informed decisions about tree species selection and placement in cities. Finding a common assessment framework, that does not rely on a financial model, can be tricky, and many studies consider, but do not include, EDS in their tree appraisals. Compound indicators represent a means to neatly combine disparate ecosystem data into one meaningful metric. In this study quantitative field measurements, model outputs, and categorical data relating to some of the major ES and EDS of the urban forest of Meran, Italy, were successfully compressed into a single unit, overcoming epistemological boundaries surrounding different urban ecosystem valuation methods. Several methods of compound indicator construction were considered and uncertainty and sensitivity analysis carried out on the species rankings which were produced. Significant differences in ES/EDS provision were observed between trees on public and private land. Spatial analysis revealed hotspots of high ES provision and low EDS provision, and vice versa. With correct use, compound indicators can stand alongside other methods of measuring and valuing positive and negative aspects of urban ecosystems. © 2018 The Authors

Additional file 4. Correlations between number of germinated diagnostic species of the main vegetation types of Asinara island with number of viable species in the dung of donkeys and goats with rs and p value.

Bioindicators are organisms able to provide indirectly or directly information on the impact of pollutants in the environment. The content of heavy metals or other toxic compounds in these living organisms is of great interest to assess the level of contaminants. Leaves of the most common deciduous trees (Acer pseudoplatanus L., Betula pendula Roth, Carpinus betulus L., Cercis siliquastrum L., Ginkgo biloba L., Liquidambar styraciflua, Quercus robur L. and Tilia cordata Miller) and two invasive tree species Ailanthus altissima P. Mill. and Robinia pseudoacacia L., in the City of Bolzano (southern Alps in Northern Italy), were therefore studied to assess their suitability as bioindicators for the trace elements Cd, Cu, Mn, Pb, and Zn, mainly considered as traffic related elements. Leaves and soil samples were investigated, both from high-density traffic roads and control sites of minor traffic impact, such as parks. Our data reveal that Betula pendula has a considerable Zn accumulation potential compared to the other investigated tree species. The maximum value measured for Zn in a Betula specimen is 200 mg kg-1 dry weight. With regard to the soils, considering the geoaccumulation index, most of the analyzed soils belong to the first class, i. e. uncontaminated (Igeo ≤ 0) for all analyzed elements. Moreover, in several samples collected in high traffic areas, Cu and Zn show values within 1 < Igeo ≤ 2 (moderately contaminated). This allows to hypothesize a traffic-related origin for these elements. For this reason, B. pendula can be considered a potential heavy metal accumulator and therefore a good bioindicator for these urban pollutants. Since B. pendula is widely distributed in urban areas in Central and Northern Europe, it can be considered a species suitable for a systematic and comparative monitoring network. Bioindikatoren sind Organismen, die Informationen über die Auswirkungen von Schadstoffen in der Umwelt direkt oder indirekt bereitstellen. Den Gehalt von Schwermetallen und anderen toxischen Verbindungen in diesen Organismen zu bestimmen, ist von großem Interesse, um die Schadstoffbelastung der Umwelt zu bewerten. Daher wurden Blätter der häufigsten Laubbäume entlang der Straßen in der Stadt Bozen (S-Alpen in Norditalien) untersucht, namentlich von Acer pseudoplatanus L., Ailanthus altissima P. Mill., Betula pendula Roth, Carpinus betulus L., Cercis siliquastrum L., Ginkgo biloba L., Liquidambar styraciflua, Quercus robur L., Robinia pseudoacacia L. und Tilia cordata Miller, um deren Eignung als Bioindikatoren für die Spurenelemente Cd, Cu, Mn, Pb und Zn zu bewerten. Blätter und Bodenproben von Straßen mit hoher Verkehrsbelastung wurden mit denen mit geringer Verkehrsbelastung (z. B. Parks) verglichen. Unsere Daten belegen, dass Betula pendula ein erhebliches Akkumulationspotenzial von Zn im Vergleich zu den anderen untersuchten Baumarten hat. Der Maximalwert für Zn in einer Blattprobe der Birke beträgt 200 mg kg-1 Trockengewicht. Bezüglich des bodenkundlichen geoaccumulation index gehören die meisten der untersuchten Böden für alle analysierten Elemente zur ersten Klasse, das heißt „unbelastet“ (Igeo ≤ 0). Allerdings weisen Proben von stark verkehrsbelasteten Straßen Cu- und Zn-Werte von 1 < Igeo ≤ 2, d. h. „mäßig belastet“ auf. Dies lässt auf die Herkunft dieser Elemente aus dem Straßenverkehr schließen. Mit ihrer Eigenschaft Schwermetalle anzureichern, wurde die Birke (B. pendula) als ein potenzieller Bioindikator in Städten identifiziert. Da B. pendula in Stadtgebieten Mittel- und Nordeuropas weit verbreitet ist, scheint die Art für ein systematisches und vergleichendes Monitoring geeignet zu sein.

In G. T. Cirella & S. Zerbe (Eds.), Sustainable Water Management and Wetland Restoration Strategies in Northern China (pp. 1���10).

In G. T. Cirella & S. Zerbe (Eds.), Sustainable Water Management and Wetland Restoration Strategies in Northern China (pp. 137���155).

In G. T. Cirella & S. Zerbe (Eds.), Sustainable Water Management and Wetland Restoration Strategies in Northern China (pp. 173���187).

In G. T. Cirella & S. Zerbe (Eds.), Sustainable Water Management and Wetland Restoration Strategies in Northern China (pp. 69���81).