ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

1

Electronic Resource

15N-ammonium and 15N-nitrate uptake of a 15-year-old Picea abies plantation (1995)

Buchmann, N. ; Schulze, E.-D. ; Gebauer, G.

Springer

Oecologia 102 (1995), S. 361-370

add to mindlist on the mindlist

Details

ISSN: 1432-1939

Keywords: Picea abies (L.) Karst ; Ammonium ; Nitrate ; 15N ; Tracer

Source: Springer Online Journal Archives 1860-2000

Topics: Biology

Notes: Abstract Throughfall nitrogen of a 15-year-old Picea abies (L.) Karst. (Norway spruce) stand in the Fichtelgebirge, Germany, was labeled with either 15N-ammonium or 15N-nitrate and uptake of these two tracers was followed during two successive growing seasons (1991 and 1992). 15N-labeling (62 mg 15N m-2 under conditions of 1.5 g N m-2 atmospheric nitrogen deposition) did not increase N concentrations in plant tissues. The 15N recovery within the entire stand (including soils) was 94%±6% of the applied 15N-ammonium tracer and 100%±6% of the applied 15N-nitrate tracer during the 1st year of investigation. This decreased to 80%±24% and 83%±20%, respectively, during the 2nd year. After 11 days, the 15N tracer was detectable in 1-year-old spruce needles and leaves of understory species. After 1 month, tracer was detectable in needle litter fall. At the end of the first growing season, more than 50% of the 15N taken up by spruce was assimilated in needles, and more than 20% in twigs. The relative distribution of recovered tracer of both 15N-ammonium and 15N-nitrate was similar within the different foliage age classes (recent to 11-year-old) and other compartments of the trees. 15N enrichment generally decreased with increasing tissue age. Roots accounted for up to 20% of the recovered 15N in spruce; no enrichment could be detected in stem wood. Although 15N-ammonium and 15N-nitrate were applied in the same molar quantities (15NH 4 + : 15NO 3 - =1:1), the tracers were diluted differently in the inorganic soil N pools (15NH 4 + /NH 4 + : 15NO 3 - /NO 3 - =1:9). Therefore the measured 15N amounts retained by the vegetation do not represent the actual fluxes of ammonium and nitrate in the soil solution. Use of the molar ammonium-to-nitrate ratio of 9:1 in the soil water extract to estimate 15N uptake from inorganic N pools resulted in a 2–4 times higher ammonium than nitrate uptake by P. abies.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00329803

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

2

Electronic Resource

Growth, photosynthesis and storage of carbohydrates and nitrogen in Phaseolus lunatus in relation to resource availability (1995)

Mooney, H. A. ; Fichtner, K. ; Schulze, E.-D.

Springer

Oecologia 104 (1995), S. 17-23

add to mindlist on the mindlist

Details

ISSN: 1432-1939

Keywords: Carbohydrate ; Growth ; Nitrogen ; Phaseolus lunatus ; Storage

Source: Springer Online Journal Archives 1860-2000

Topics: Biology

Notes: Abstract Growth, photosynthesis, and storage of nitrogen (N) and total non-structural carbohydrates (TNC) of a perennial wild type and an annual cultivar of lima bean (Phaseolus lunatus) were examined at different light intensities and N supplies. Relative growth rate and photosynthesis increased with light and N availability. N limitation enhanced biomass allocation into root rather than into shoot, while light limitation enhanced growth of leaf area. The TNC concentrations increased with light intensity and thus with photosynthesis, while the concentrations of organic N and nitrate decreased. Increasing N supply had the opposite effect. Therefore, TNC and organic N concentrations were negatively correlated (r=−0.90). Pool size of N or TNC increased with N and light availability when either resource was non-limiting, but increased little or remained constant when either resource was limiting. Storage reached a minimum when both resources were supplied at an equal rate.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00365557

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

3

Electronic Resource

Decreased ribulose-1,5-bisphosphate carboxylase-oxygenase in transgenic tobacco transformed with “antisense” rbcS (1991)

Quick, W. P. ; Schurr, U. ; Scheibe, R. ; [et al.]

Springer

Planta 183 (1991), S. 542-554

add to mindlist on the mindlist

Details

ISSN: 1432-2048

Keywords: Nicotiana (transformed with antisense DNA) ; Photosynthesis ; Ribulose-1,5-bisphosphate carboxylase-oxygenase ; Transgenic plant (antisense)

Source: Springer Online Journal Archives 1860-2000

Topics: Biology

Notes: Abstract Experiments were carried out to determine how decreased expression of ribulose-1,5-bisphosphate carboxylase-oxygenase (Rubisco) affects photosynthetic metabolism in ambient growth conditions. In a series of tobacco (Nicotiana tabacum L.) plants containing progressively smaller amounts of Rubisco the rate of photosynthesis was measured under conditions similar to those in which the plants had been grown (310 μmol photons · m−2 · s−1, 350 μbar CO2, 22° C). (i) There was only a marginal inhibition (6%) of photosynthesis when Rubisco was decreased to about 60% of the amount in the wildtype. The reduced amount of Rubisco was compensated for by an increase in Rubisco activation (rising from 60 to 100%), with minor contributions from an increase of its substrates (ribulose-1,5-bisphosphate and the internal CO2 concentration) and a decrease of its product (glycerate-3-phosphate). (ii) The decreased amount of Rubisco was accompanied by an increased ATP/ADP ratio that may be causally linked to the increased activation of Rubisco. An increase of highenergy-state chlorophyll fluorescence shows that thylakoid membrane energisation and high-energy-state-dependent energy dissipation at photosystem two had also increased. (iii) A further decrease of Rubisco (in the range of 50–20% of the wildtype level) resulted in a strong and proportional inhibition of CO2 assimilation. This was accompanied by a decrease of fructose-1,6-bisphosphatase activity, coupling-factor 1 (CF1)-ATP-synthase protein, NADP-malate dehydrogenase protein, and chlorophyll. The chlorophyll a/b ratio did not change, and enolase and sucrose-phosphate synthase activity did not decrease. It is argued that other photosynthetic enzymes are also decreased once Rubisco decreases to the point at which it becomes strongly limiting for photosynthesis. (iv) It is proposed that the amount of Rubisco in the wildtype represents a balance between the demands of light, water and nitrogen utilisation. The wildtype overinvests about 15% more protein in Rubisco than is needed to avoid a strict Rubisco limitation of photosynthesis. However, this “excess” Rubisco allows the wildtype to operate with lower thylakoid energisation, and decreased high-energy-state-dependent energy dissipation, hence increasing light-use efficiency by about 6%. It also allows the wildtype to operate with a lower internal CO2 concentration in the leaf and a lower stomatal conductance at a given rate of photosynthesis, so that instantaneous water-use efficiency is marginally (8%) increased.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00194276

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

4

Electronic Resource

Nitrogen and carbohydrate storage in biennials originating from habitats of different resource availability (1993)

Steinlein, T. ; Heilmeier, H. ; Schulze, E.-D.

Springer

Oecologia 93 (1993), S. 374-382

add to mindlist on the mindlist

Details

ISSN: 1432-1939

Keywords: Storage ; Accumulation ; Reserve formation ; Storage structure ; Biennial plants

Source: Springer Online Journal Archives 1860-2000

Topics: Biology

Notes: Abstract Four biennial species (Arctium tomentosum, Cirsium vulgare, Dipsacus sylvester and Daucus carota) which originate from habitats of different nutrient availability were investigated in a 2-year experiment in a twofactorial structured block design varying light (natural daylight versus shading) and fertilizer addition. The experiment was designed to study storage as reserve formation (competing with growth) or as accumulation (see Chapin et al. 1990). We show that (i) the previous definitions of storage excluded an important process, namely the formation of storage tissue. Depending on species, storage tissue and the filling process can be either a process of reserve formation, or a process of accumulation. (ii) In species representing low-resource habitats, the formation of a storage structure competes with other growth processes. Growth of storage tissue and filling with storage products is an accumulation process only in the high-resource plant Arctium tomentosum. We interpret the structural growth of low-resource plants in terms of the evolutionary history of these species, which have closely related woody species in the Mediterranean area. (iii) The use of storage products for early leaf growth determines the biomass development in the second season and the competitive ability of this species during growth with perennial species. (iv) The high-resource plant Arctium has higher biomass development under all conditions, i.e. plants of low-resource habitats are not superior under low-resource conditions. The main difference between high- and low-resource plants is that low-resource plants initiate flowering at a lower total plant internal pool size of available resources.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00317881

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

5

Electronic Resource

Carbon and nitrogen partitioning in the biennial monocarp Arctium tomentosum Mill (1986)

Heilmeier, H. ; Schulze, E. -D. ; Whale, D. M.

Springer

Oecologia 70 (1986), S. 466-474

add to mindlist on the mindlist

Details

ISSN: 1432-1939

Keywords: Biennial plants ; Carbon partitioning ; Nitrogen partitioning ; Storage ; Harvest index

Source: Springer Online Journal Archives 1860-2000

Topics: Biology

Notes: Summary Growth and nitrogen partitioning were investigated in the biennial monocarp Arctium tomentosum in the field, in plants growing at natural light conditions, in plants in which approximately half the leaf area was removed and in plants growing under 20% of incident irradiation. Growth quantities were derived from splined cubic polynomial exponential functions fitted to dry matter, leaf area and nitrogen data. Main emphasis was made to understanding of the significance of carbohydrate and nitrogen storage of a large tuber during a 2-years' life cycle, especially the effect of storage on biomass and seed yield in the second season. Biomass partitioning favours growth of leaves in the first year rosette stage. Roots store carbohydrates at a constant rate and increase storage of carbohydrates and nitrogen when the leaves decay at the end of the first season. In the second season the reallocation of carbohydrates from storage is relatively small, but reallocation of nitrogen is very large. Carbohydrate storage just primes the growth of the first leaves in the early growing season, nitrogen storage contributes 20% to the total nitrogen requirement during the 2nd season. The efficiency of carbohydrate storage for conversion into new biomass is about 40%. Nitrogen is reallocated 3 times in the second year, namely from the tuber to rosette leaves and further to flower stem leaves and eventually into seeds. The harvest index for nitrogen is 0.73, whereas for biomass it is only 0.19.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00379513

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

6

Electronic Resource

Carbon uptake and respiration in above-ground parts of a Larix decidua × leptolepis tree (1988)

Matyssek, R. ; Schulze, E. D.

Springer

Trees 2 (1988), S. 233-241

add to mindlist on the mindlist

Details

ISSN: 1432-2285

Keywords: Larix ; Carbon uptake ; Respiration ; Carbon balances ; Water loss ; Sun and shade branches

Source: Springer Online Journal Archives 1860-2000

Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Notes: Summary Shade needles of hybrid larch (Larix decidua × leptolepis) had the same rates of photosynthesis as sun needles per dry weight and nitrogen, and a similar leaf conductance under conditions of light saturation at ambient CO2 (Amax). However, on an area basis, Amax and specific leaf weight were lower in shade than in sun needles. Stomata of sun needles limited CO2 uptake at light saturation by about 20%, but under natural conditions of light in the shade crown, shade needles operated in a range of saturating internal CO2 without stomatal limitation of CO2 uptake. In both needle types, stomata responded similarly to changes in light, but shade needles were more sensitive to changes in vapor pressure deficit than sun needles. Despite a high photosynthetic capacity, the ambient light conditions reduced the mean daily (in summer) and annual carbon gain of shade needles to less than 50% of that in sun needles. In sun needles, the transpiration per carbon gain was about 220 mol mol−1 on an annual basis. The carbon budget of branches was determined from the photosynthetic rate, the needle biomass and respiration, the latter of which was (per growth and on a carbon basis) 1.6 mol mol−1 year−1 in branch and stem wood. In shade branches carbon gains exceeded carbon costs (growth + respiration) by only a factor of 1.6 compared with 3.5 in sun branches. The carbon balance of sun branches was 5 times higher per needle biomass of a branch or 9 times higher on a branch length basis than shade branches. The shade foliage (including the shaded near-stem sun foliage) only contributed approximately 23% to the total annual carbon gain of the tree.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00202378

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

7

Electronic Resource

Decreased ribulose-1,5-bisphosphate carboxylase-oxygenase in transgenic tobacco transformed with ‘antisense’ rbcS (1991)

Stitt, M. ; Quick, W. P. ; Schurr, U. ; [et al.]

Springer

Planta 183 (1991), S. 555-566

add to mindlist on the mindlist

Details

ISSN: 1432-2048

Keywords: Flux control (photosynthesis) ; Nicotiana (transformed with antisense DNA) ; Ribulose-1,5-bisphosphate carboxylase-oxygenase (control of photosynthesis) ; Transgenic plant (antisense)

Source: Springer Online Journal Archives 1860-2000

Topics: Biology

Notes: Abstract Transgenic tobacco (Nicotiana tabacum L.) plants transformed with ‘antisense’ rbcS to produce a series of plants with a progressive decrease in the amount of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) have been used to investigate the contribution of Rubsico to the control of photosynthesis at different irradiance, CO2 concentrations and vapour-pressure deficits. Assimilation rates, transpiration, the internal CO2 concentration and chlorophyll fluorescence were measured in each plant. (i) The flux-control coefficient of Rubisco was estimated from the slope of the plot of Rubisco content versus assimilation rate. The flux-control coefficient had a value of 0.8 or more in high irradiance, (1050 μmol·m−2·s−1), low-vapour pressure deficit (4 mbar) and ambient CO2 (350 μbar). Control was marginal in enhanced CO2 (450 μbar) or low light (310 μmol·m−2·s−1) and was also decreased at high vapour-pressure deficit (17 mbar). No control was exerted in 5% CO2. (ii) The flux-control coefficients of Rubisco were compared with the fractional demand placed on the calculated available Rubisco capacity. Only a marginal control on photosynthetic flux is exerted by Rubisco until over 50% of the available capacity is being used. Control increases as utilisation rises to 80%, and approaches unity (i.e. strict limitation) when more than 80% of the available capacity is being used. (iii) In low light, plants with reduced Rubisco have very high energy-dependent quenching of chlorophyll fluorescence (qE) and a decreased apparent quantum yield. It is argued that Rubisco still exerts marginal control in these conditions because decreased Rubisco leads to increased thylakoid energisation and high-energy dependent dissipation of light energy, and lower light-harvesting efficiency. (iv) The flux-control coefficient of stomata for photosynthesis was calculated from the flux-control coefficient of Rubisco and the internal CO2 concentration, by applying the connectivity theorem. Control by the stomata varies between zero and about 0.25. It is increased by increased irradiance, decreased CO2 or decreased vapour-pressure deficit. (v) Photosynthetic oscillations in saturating irradiance and CO2 are suppressed in decreased-activity transformants before the steady-state rate of photosynthesis is affected. This provides direct evidence that these oscillations reveal the presence of “excess” Rubisco. (vi) Comparison of the flux-control coefficients of Rubisco with mechanistic models of photosynthesis provides direct support for the reliability of these models in conditions where Rubisco has a flux-control coefficient approach unity (i.e. “limits” photosynthesis), but also indicates that these models are less useful in conditions where control is shared between Rubisco and other components of the photosynthetic apparatus.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00194277

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext