ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Elevated CO2 and temperature effects on soil carbon and nitrogen cycling in ryegrass/white clover turves of an Endoaquept soil (1995)
    Springer
    Plant and soil 176 (1995), S. 37-49 
    Details
    ISSN: 1573-5036
    Keywords: C cycling ; climate change ; elevated CO2 ; microbial biomass ; N mineralization ; soil respiration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Effects of elevated CO2 (700 μL L−1) and a control (350 μL L−1 CO2) on the productivity of a 3-year-old ryegrass/white clover pasture, and on soil biochemical properties, were investigated with turves of a Typic Endoaquept soil in growth chambers. Temperature treatments corresponding to average winter, spring, and summer conditions in the field were applied consecutively to all of the turves. An additional treatment, at 700 μL L−1 CO2 and a temperature 6°C higher throughout than in the other treatments, was included. Under the same temperature conditions, overall herbage yields in the ‘700 μL L−1 CO2’ treatment were ca. 7% greater than in the control at the end of the ‘summer’ period. Root mass (to ca 25 cm depth) in the ‘700 μL L−1 CO2’ treatment was then about 50% greater than in the control, but in the ‘700 μL L−1 CO2+6°C’ treatment it was 6% lower than in the control. Based on decomposition results, herbage from the ‘700 μL L−1+6°C’ treatment probably contained the highest proportion of readily decomposable components. Elevated CO2 had no consistent effect on soil total C and N, microbial C and N, or extractable C concentrations in any of the treatments. Under the same temperature conditions, it did, however, enhance soil respiration (CO2-C production) and invertase activity. The effects of elevated CO2 on rates of net N mineralization were less distinct, and the apparent availability of N for the sward was not affected. Under elevated CO2, soil in the higher-temperature treatment had a higher microbial C:N ratio; it also had a greater potential to degrade plant materials. Data interpretation was complicated by soil spatial variability and the moderately high background levels of organic matter and biochemical properties that are typical of New Zealand pasture soils. More rapid cycling of C under CO2 enrichment is, nevertheless, indicated. Futher long-term experiments are required to determine the overall effect of elevated CO2 on the soil C balance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00017673
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Soil restoration under pasture after topsoil removal: Some factors influencing C and N mineralization and measurements of microbial biomass (1990)
    Springer
    Plant and soil 127 (1990), S. 49-59 
    Details
    ISSN: 1573-5036
    Keywords: microbial biomass ; mineral-N flush ; nitrogen mineralization ; pasture plants ; soil respiration ; soil restoration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Factors influencing rates of C and N mineralization of soil and plant materials, and the reliability of different procedures for estimating microbial biomass, were measured in a soil (Typic Dystrochrept) that had been restored under grazed pasture in a temperate environment for 10–11 years after 20 cm of the original topsoil had been removed by stripping. Rates of net N mineralization were appreciably lower, but CO2-C production higher, in the stripped than in the unstripped soil. These activities were not influenced directly by levels of soil mineral-N, but they were influenced by differences in plant composition. Herbage and litter, and roots, from the stripped plots were generally mineralized more readily to CO2-C, but more slowly to net mineral-N, than were the corresponding materials from the unstripped plots. Rates of mineralization of herbage and litter, or roots, were mainly indistinguishable in stripped and unstripped soil, whereas rates of mineralization of all standing dead material were lower in stripped soil. Measurements of extractable-C flush, and of CO2-C flush (using a fumigated soil control) and mineral-N flush by fumigation-incubation procedures, indicated that microbial biomass in stripped soil had recovered to at least 88 percent of the levels in unstripped soil. Substrate-induced respiration also generally indicated high levels of recovery of microbial biomass. The fumigation-incubation procedure appeared to under-estimate microbial biomass markedly in stripped soil when unfumigated soil controls were used; the used of a large soil inoculum (20 percent w/w) only sometimes overcame this problem. Possible reasons for apparent anomalies in estimation of microbial C are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00010836
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Microbial biomass C and N, and mineralizable-N, in litter and mineral soil under Pinus radiata on a coastal sand: Influence of stand age and harvest management (1995)
    Springer
    Plant and soil 175 (1995), S. 167-177 
    Details
    ISSN: 1573-5036
    Keywords: coastal sand ; forest ; harvest management ; microbial biomass ; nitrogen mineralization ; organic matter ; Radiata pine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Microbial biomass C and N, and anaerobically mineralizable-N, were measured in the litter and mineral soil (0–10 cm and 10–20 cm depth) of Pinus radiata plantations in two trials on a nitrogen-deficient coastal sand. The trials comprised (a) stands of different age (1 to 33 years), with five of the seven stands studied being second rotation, and (b) a harvest-management trial, with stands established after different harvesting treatments of the first-rotation trees and understorey development controlled by manual weeding and chemical sprays. The harvest-management stands were sampled in the fifth year after the second-rotation establishment. In the stands of different age, the levels of microbial biomass C and N, and also mineralizable-N, in the litter and mineral soil showed no relationship with tree age and were similar to those in the oldest (33 years) stands of P. radiata. In the harvesting trial, five years after establishment of the second rotation, levels of microbial N and mineralizable-N in the litter and mineral soil were generally lowest where whole trees and the original forest floor had been removed; they were higher in associated plots in which the original forest floor had been removed but fertilizer N was regularly applied. No marked differences were then found between the other harvest treatments, viz. whole-tree harvest, stem-only harvest with slash remaining on site, and stem-only harvest plus extra added slash materials. In each trial, levels of microbial C and N and mineralizable-N were closely related to total C, and especially total N, in 0–10 cm depth mineral soil, but not generally in litter. Respiratory measurements strongly suggest that the microbial populations in mineral soil had a high metabolic activity. On an area basis in the harvest-management trial, total tree N and microbial N in the litter and mineral soil were lowest in stands where the original forest floor had been removed. In this particular treatment, microbial N in the litter plus mineral soil (0–20 cm depth) after five years of second-rotation growth comprised 7.3% of the total ecosystem N; values in the other treatments ranged between 5.6 and 6.0%. Our results emphasise the importance of slash and litter, and probably volunteer shrubs and herbaceous under-storey species, in conserving pools of potentially available N during the early stages of tree development.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00011352
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Elevated CO2 effects on carbon and nitrogen cycling in grass/clover turves of a Psammaquent soil (1996)
    Springer
    Plant and soil 182 (1996), S. 185-198 
    Details
    ISSN: 1573-5036
    Keywords: C cycling ; elevated CO2 ; microbial biomass ; N mineralization ; plant decomposition ; soil respiration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Effects of elevated CO2 (525 and 700 μL L−1), and a control (350 μL L−1 CO2), on biochemical properties of a Mollic Psammaquent soil in a well-established pasture of C3 and C4 grasses and clover were investigated with continuously moist turves in growth chambers over four consecutive seasonal temperature regimes from spring to winter inclusive. After a further ‘spring’ period, half of the turves under 350 and 700 μL L−1 were subjected to ‘summer’ drying and were then re-wetted before a further ‘autumn’ period; the remaining turves were kept continuously moist throughout these additional three consecutive ‘seasons’. The continuously moist turves were then pulse-labelled with 14C-CO2 to follow C pathways in the plant/soil system during 35 days. Growth rates of herbage during the first four ‘seasons’ averaged 4.6 g m−2 day−1 under 700 μL L−1 CO2 and were about 10% higher than under the other two treatments. Below-ground net productivity at the end of these ‘seasons’ averaged 465, 800 and 824 g m−2 in the control, 525 and 700 μL L−1 treatments, respectively. in continuously moist soil, elevated CO2 had no overall effects on total, extractable or microbial C and N, or invertase activity, but resulted in increased CO2-C production from soil, and from added herbage during the initial stages of decomposition over 21 days; rates of root decomposition were unaffected. CO2 produced h−1 mg−1 microbial C was about 10% higher in the 700 μL L−1 CO2 treatment than in the other two treatments. Elevated CO2 had no clearly defined effects on N availability, or on the net N mineralization of added herbage. In the labelling experiment, relatively more 14C in the plant/soil system occurred below ground under elevated CO2, with enhanced turnover of 14C also being suggested. Drying increased levels of extractable C and organic-N, but decreased mineral-N concentrations; it had no effect on microbial C, but resulted in lowered microbial N in the control only. In soil that had been previously ‘summer’-dried, CO2 production was again higher, but net N mineralization was lower, under elevated CO2 than in the control after ‘autumn’ pasture growth. Over the trial period of 422 days, elevated CO2 generally appears to have had a greater effect on soil C turnover than on soil C pools in this pasture ecosystem.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00029050
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Soil restoration under pasture after lignite mining: Management effects on soil biochemical properties and their relationships with herbage yields (1992)
    Springer
    Plant and soil 140 (1992), S. 85-97 
    Details
    ISSN: 1573-5036
    Keywords: invertase ; lignite mining ; microbial biomass ; nitrogen mineralization ; pasture production ; soil restoration ; sulphatase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The recovery of soil biochemical properties under grazed, grass-clover pasture, after simulated lignite mining, was studied over a 5-year period in a mesic Typic Dystrochrept soil at Waimumu, Southland, New Zealand. The restoration procedures involved four replacement treatments, after A, B, and C horizon materials had been separately removed, from all except the control, and stockpiled for 2–3 weeks. In each replacement treatment, the effects of ripping to 1.8 m depth, mole drainage, and the use of fertilizer nitrogen were also investigated. Replacement treatment markedly influenced the recovery of herbage production and soil organic C and total N contents, N mineralization, microbial biomass (as indicated by mineral-N flush) and invertase and sulphatase activities. The effectiveness of replacement treatments decreased in the order: 1. control (no stripping or replacement). 2 A, B, and C horizon materials replaced in the same order. 3. A, B, and C horizon materials each mixed with an equal amount of siltstone overburden and replaced in order, 4. A and B horizon materials mixed before replacing over C horizon material. Ripping increased herbage production, net N mineralization, and to some extent microbial biomass. Drainage had little, if any, effect. Fertilizer N also stimulated herbage production, but depressed clover growth. Over 2.5 years, it had little detectable effect on the soil properties. Increases in soil invertase and, to a lesser extent, sulphatase activity during the trial were closely related to changes in herbage production. Microbial biomass increased more rapidly than did soil organic C in the early stages of the trial. Rates of net N mineralization strongly suggest that N availability would have limited pasture growth, especially in the treatments with mixed soil materials.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00012810
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...