X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Soil formation, nutrient supply and ecosystem productivity on basaltic lava vs rhyolitic pumice on Alcedo Volcano, Galápagos
    CSIRO Publishing ; 2021
    In:  Soil Research Vol. 60, No. 2 ( 2021-11-4), p. 173-186
    Details
    In: Soil Research, CSIRO Publishing, Vol. 60, No. 2 ( 2021-11-4), p. 173-186
    Abstract: Context Rock type may exert strong control on pedogenesis and resulting soil characteristics. Little is known on how different volcanic lithologies influence soil formation and nutrient supply and thereby affect ecosystem productivity in volcanic landscapes. Aims The aim of this study was to investigate lithologic control on the mentioned properties and processes. Methods We conducted a side-by-side comparison of two contrasting sites in close proximity on Alcedo Volcano, Galápagos, one on basaltic lava and the other on rhyolitic pumice. Key results The lava site was covered by lush, stratified woodland, whereas the pumice site was covered by grassland with only few plant species. The soil on lava was a Leptosol, whereas on pumice, an Andosol had formed. Both soils had similar pH (6.0–6.5 in H2O), but the soil organic carbon stocks at the lava site were almost twice as high as at the pumice site (13.1 ± 1.6 vs 7.6 ± 1.3 kg m−2 to 25 cm depth). The soil at the pumice site had considerably lower levels of Mehlich-3-extractable P, Ca, Mg, Cu, Zn and B. Soil microbes at the pumice site had lower biomass P (and a higher C:P ratio) and excreted more phosphatase. The grass biomass here also showed lower (and deficient) levels of P and other nutrients compared to the lava site. Conclusions and implications The contrasting lithologies and their bearings on soil formation and nutrient availability diversify the aboveground and belowground ecosystems and favour the development of distinct ecological niches in close proximity.
    Type of Medium: Online Resource
    ISSN: 1838-675X , 1838-6768
    URL: Article
    DOI: 10.1071/SR21148
    Language: English
    Publisher: CSIRO Publishing
    Publication Date: 2021
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 2
    Online Resource
    Online Resource
    Capillary electrophoresis characterisation of humic acids: application to diverse forest soil samples
    CSIRO Publishing ; 2011
    In:  Environmental Chemistry Vol. 8, No. 6 ( 2011), p. 589-
    Details
    In: Environmental Chemistry, CSIRO Publishing, Vol. 8, No. 6 ( 2011), p. 589-
    Abstract: Environmental contextAnalysis of soil organic matter is important for understanding turnover and stabilisation processes of organic carbon in soils. Capillary electrophoresis is used here to investigate humic acids from soils of diverse forest sites, and show that the patterns of signals are indicative of soil characteristics. The method provides useful information of soil types and complements the existing set of methods for humic acid characterisation. AbstractAnalyses of humic substances provide very useful information about turnover characteristics and stabilisation processes of soil organic matter in environmental soil samples. The present study investigates 113 samples of forest soils from three different layers (undecomposed litter (L), if present, mixed samples of F (intermediate decomposed) and H (highly decomposed) organic matter (FH) and upper mineral soil layers (Ah horizon) from 0 to 5 cm) by extracting humic acids (HAs) and recording electropherograms. Five signals of these electropherograms were evaluated and correlated with basic parameters from soil (organic carbon, Corg, and total nitrogen, Nt, and extraction yields of HAs) and HAs (total carbon, Ct, and Nt), and with signals from photometry, mid-infrared and fluorescence spectroscopy. The developed method was able to separate HAs from different soil layers by calculating a discriminant function based on the five evaluated electrophoretic signals. The dataset of this work opened the opportunity to correlate the observed electrophoretic signals with the other determined soil parameters and spectroscopic signals. This can be seen as a very important step in the direction to assignments of the obtained electrophoretic signals. Soil characteristics were reflected quite well by this method and, combined with the other approaches, it is suitable for applications in further studies.
    Type of Medium: Online Resource
    ISSN: 1448-2517
    URL: Article
    DOI: 10.1071/EN11054
    Language: English
    Publisher: CSIRO Publishing
    Publication Date: 2011
    detail.hit.zdb_id: 2150372-2
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 3
    Online Resource
    Online Resource
    Spectroscopic behaviour of 14C-labeled humic acids in a long-term field experiment with three cropping systems
    CSIRO Publishing ; 2009
    In:  Soil Research Vol. 47, No. 5 ( 2009), p. 459-
    Details
    In: Soil Research, CSIRO Publishing, Vol. 47, No. 5 ( 2009), p. 459-
    Abstract: The stabilisation of 14C-labelled farmyard manure was investigated under different cropping systems (crop rotation, monoculture, and bare fallow) in a long-term field experiment established in 1967. Solid-state 13C-NMR of bulk soils yielded a gradient of increasing aromatic properties in the order: straw manure–crop rotation  〈  straw manure–monoculture  〈  straw and farmyard manure–bare fallow. The opposite trend was observed for O-alkyl groups. The farmyard manure–bare fallow treatment was used to investigate changes of humic acids (HAs) with time. The FT-IR bands of aromatics, carbonyl groups, and a band of methyls and benzene rings increased over the 36 years of the experiment, whereas 2 amide bands and a band of sulfone and/or ester groups decreased. Fluorescence spectroscopy verified the increase in aromatic properties with age. Consequently, during soil organic matter stabilisation, HAs showed increasing properties of carbonyl and aromatic groups, whereas amidic groups decreased. The dynamic character of HAs, as shown by 14C, was also reflected by distinct spectroscopic changes over the period of investigation.
    Type of Medium: Online Resource
    ISSN: 1838-675X
    URL: Article
    DOI: 10.1071/SR08231
    Language: English
    Publisher: CSIRO Publishing
    Publication Date: 2009
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 4
    Online Resource
    Online Resource
    Agriculture changes soil properties on the Galápagos Islands – two case studies
    CSIRO Publishing ; 2019
    In:  Soil Research Vol. 57, No. 3 ( 2019), p. 201-
    Details
    In: Soil Research, CSIRO Publishing, Vol. 57, No. 3 ( 2019), p. 201-
    Abstract: The Galápagos Islands have faced a huge rise in the number of inhabitants and tourists over recent decades. As a consequence, natural forest vegetation has been converted to arable land to meet the increasing demand for agricultural produce. However, studies on soils and soil use change in the Galápagos Islands are scarce. In this study, we assessed the impacts of agricultural land-use on the islands of Santa Cruz and San Cristóbal. The site on Santa Cruz was called El Cascajo (EC, Leptosol, 5 years after conversion to intensive agriculture) and that on the oldest island of the Galápagos archipelago, San Cristóbal, Cerro Verde (CV, Ferralsol, 15 years after conversion). At both sites, we compared arable soils to soils under forests within the adjacent Galápagos National Park, which had formed on the same parent materials. Several soil properties showed a significant impact of the arable use. Soil organic carbon (Corg) stocks were relatively high at both sites (between 94 ± 28 and 142 ± 10 Mg ha–1). At CV, the stocks were 25% lower in arable plots compared with natural forest, but the observed decrease at EC was non-significant. Many other parameters like total nitrogen and several Mehlich-III extractable nutrients were closely correlated with the changes in Corg. Microbial biomass carbon (Cmic) and dissolved organic carbon were significantly lower in arable plots compared with forest at both sites. At EC, Cmic/Corg dropped by a factor of 1.9. Changes in pH and the use of agrochemicals, evidenced by pesticide residues detected in the soil, might be a possible explanation. Ammonium-N decreased and nitrate-N increased tremendously in the arable plots on both islands. Our research shows that present agricultural practices have potential for improvements towards a more sustainable agricultural use of soil resources on the Galápagos Islands.
    Type of Medium: Online Resource
    ISSN: 1838-675X
    URL: Article
    DOI: 10.1071/SR18331
    Language: English
    Publisher: CSIRO Publishing
    Publication Date: 2019
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
Nothing or not found what you are looking for? Please check your search query or use the Interlibrary Loan Search.
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages