scholarly journals Contrasting Resource Dynamics in Mast Years for European Beech and Oak—A Continental Scale Analysis

2021 ◽  
Vol 4 ◽  
Author(s):  
Anita Nussbaumer ◽  
Arthur Gessler ◽  
Sue Benham ◽  
Bruno de Cinti ◽  
Sophia Etzold ◽  
...  
Keyword(s):  
Leaf Growth ◽  
Fruit Production ◽  
Stem Growth ◽  
Leaf Production ◽  
Continental Scale ◽  
Resource Dynamics ◽  
Resource Storage ◽  
Resource Switching ◽  
The Impact ◽  
Leaf N

Resource allocation to different plant tissues is likely to be affected by high investment into fruit production during mast years. However, there is a large knowledge gap concerning species-specific differences in resource dynamics. We investigated the influence of mast years on stem growth, leaf production, and leaf carbon (C), nitrogen (N), and phosphorus (P) concentrations and contents in Fagus sylvatica, Quercus petraea, and Q. robur at continental and climate region scales using long-term data from the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) and similar datasets. We discussed the results in the light of opposing resource dynamics hypotheses: (i) resource accumulation before mast years and exhaustion after mast years (resource storage hypothesis), (ii) shifting resources from vegetative to generative compartments (resource switching hypothesis), and (iii) investing resources concurrently in both vegetative and generative compartments (resource matching hypothesis). Linear mixed-effects modelling (LMM) showed that both stem growth and leaf production were negatively influenced by weather conditions which simultaneously lead to high fruit production. Thus, the impact of generative on vegetative growth is intermixed with effects of environmental factors. Superposed epoch analyses and LMM showed that for mast behaviour in F. sylvatica, there are indicators supporting the resource storage and the resource switching hypotheses. Before mast years, resources were accumulated, while during mast years resources switched from vegetative to generative tissues with reduced stem and leaf growth. For the Quercus species, stem growth was reduced after mast years, which supports the resource storage hypothesis. LMM showed that leaf C concentrations did not change with increasing fruit production in neither species. Leaf N and P concentrations increased in F. sylvatica, but not in Quercus species. Leaf N and P contents decreased with increasing fruit production in all species, as did leaf C content in F. sylvatica. Overall, our findings suggest different resource dynamics strategies in F. sylvatica and Quercus species, which might lead to differences in their adaptive capacity to a changing climate.

scholarly journals Cambial activity of Populus tremula × Populus alba clone 717-1B4 in hydroponic culture

2006 ◽  
Vol 36 (3) ◽  
pp. 719-724 ◽  
Author(s):  
Domenico Morabito ◽  
Aurore Caruso ◽  
Sabine Carpin ◽  
Cédric Carli ◽  
Françoise Laurans ◽  
...  
Keyword(s):  
Leaf Growth ◽  
Histological Study ◽  
Secondary Growth ◽  
Cambial Activity ◽  
Wood Formation ◽  
Stem Growth ◽  
Populus Tremula ◽  
Populus Alba ◽  
Hydroponic System ◽  
The Impact

Populus tremula Michx. × Populus alba L. clone 717-1B4 plants were grown in a hydroponic system in an effort to detect cambial activity in a changing nutrient environment. The secondary growth of the stem was determined by automated measurement of radial growth, as well as by histological study. This is the first time poplar cambial activity has been recorded in a hydroponic system. Further, we demonstrate that nutrient limitations can be tested with progressive deprivation of liquid medium. The system lends itself to measurements of stomatal conductance, primary stem growth, leaf growth, and radial stem growth. In this study we found that primary and secondary growth were affected by nutrient solution limitations. This hydroponic system will be valuable in elucidating the impact of environmental, physiological, and molecular factors on cambial activity and wood formation.

The Constitutional Identity of European Micro States and the Continental Integration Mechanisms. The Influence of the Diminutive Size

ICL Journal ◽  
2020 ◽  
Vol 14 (2) ◽  
pp. 133-165
Author(s):  
Elisa Bertolini
Keyword(s):  
Foreign Relations ◽  
Council Of Europe ◽  
Continental Scale ◽  
National Tradition ◽  
Relevant Role ◽  
Integration Mechanisms ◽  
Traditional Institutions ◽  
The Impact ◽  
Constitutional Identity ◽  
The Eu

AbstractThe article analyses the impact that the diminutive size of the four continental Europe micro states has upon their constitutional arrangements and their approach toward continental integration mechanisms. Generally speaking, the international commitment toward integration mechanisms is one of the distinguishing traits of micro states. It may seem a paradox, but actually the international dimension is much more strategic for micro than for macro states. However, being micro territorial enclaves demanded certain ability from the part of European micro states when managing foreign relations in order not to be swallowed by their macro neighbours. Therefore, they carried out for centuries a cautious policy of ‘guarded openness’, trying to strike a balance between the maintenance of their traditional institutions and the need to interact on a continental scale. Constitutional systems that at a first glance are unusual may be an obstacle to integration and thus have to be reformed. However, not too much, because otherwise the whole system may implode if deprived of its original constitutional balance. The protection of national tradition and identity is conservative, in the sense that it arises from the necessity of self-preservation, rather than from ideology. The article claims that the ambivalent approach of continental Europe micro states have when interacting with macro states within the Council of Europe and the EU directly derives from their diminutive size. Furthermore, the relevant role played by the diminutive size is proved by the fact that recently the EU adopted a specific micro states approach. Hence, the article also aims at investigating how they try to strike a balance between the commitment toward self-preservation – ie their constitutional identity – and the commitment toward continental integration mechanisms.

scholarly journals Genotypic traits and tradeoffs of fast growth in silver birch, a pioneer tree

Oecologia ◽  
2021 ◽  
Author(s):  
Juha Mikola ◽  
Katariina Koikkalainen ◽  
Mira Rasehorn ◽  
Tarja Silfver ◽  
Ulla Paaso ◽  
...  
Keyword(s):  
Resource Competition ◽  
Leaf Growth ◽  
N Uptake ◽  
Insect Herbivory ◽  
Fast Growth ◽  
Grass Cover ◽  
Soil N ◽  
Fast Growing ◽  
Slow Growing ◽  
Leaf N

AbstractFast-growing and slow-growing plant species are suggested to show integrated economics spectrums and the tradeoffs of fast growth are predicted to emerge as susceptibility to herbivory and resource competition. We tested if these predictions also hold for fast-growing and slow-growing genotypes within a silver birch, Betula pendula population. We exposed cloned saplings of 17 genotypes with slow, medium or fast height growth to reduced insect herbivory, using an insecticide, and to increasing resource competition, using naturally varying field plot grass cover. We measured shoot and root growth, ectomycorrhizal (EM) fungal production using ergosterol analysis and soil N transfer to leaves using 15N-labelled pulse of NH4+. We found that fast-growing genotypes grew on average 78% faster, produced 56% and 16% more leaf mass and ergosterol, and showed 78% higher leaf N uptake than slow-growing genotypes. The insecticide decreased leaf damage by 83% and increased shoot growth, leaf growth and leaf N uptake by 38%, 52% and 76%, without differences between the responses of fast-growing and slow-growing genotypes, whereas root mass decreased with increasing grass cover. Shoot and leaf growth of fast-growing genotypes decreased and EM fungal production of slow-growing genotypes increased with increasing grass cover. Our results suggest that fast growth is genotypically associated with higher allocation to EM fungi, better soil N capture and greater leaf production, and that the tradeoff of fast growth is sensitivity to competition, but not to insect herbivory. EM fungi may have a dual role: to support growth of fast-growing genotypes under low grass competition and to maintain growth of slow-growing genotypes under intensifying competition.

Fire, people and ecosystem change in Pleistocene Australia

2016 ◽  
Vol 64 (8) ◽  
pp. 643 ◽  
Author(s):  
Christopher N. Johnson
Keyword(s):  
Fire Regimes ◽  
Ecosystem Change ◽  
Future Research ◽  
Cascading Effects ◽  
Continental Scale ◽  
The Past ◽  
The 1960S ◽  
Relationship Of ◽  
The Impact ◽  
The Relationship

Since the 1960s, Australian scientists have speculated on the impact of human arrival on fire regimes in Australia, and on the relationship of landscape fire to extinction of the Pleistocene megafauna of Australia. These speculations have produced a series of contrasting hypotheses that can now be tested using evidence collected over the past two decades. In the present paper, I summarise those hypotheses and review that evidence. The main conclusions of this are that (1) the effects of people on fire regimes in the Pleistocene were modest at the continental scale, and difficult to distinguish from climatic controls on fire, (2) the arrival of people triggered extinction of Australia’s megafauna, but fire had little or no role in the extinction of those animals, which was probably due primarily to hunting and (3) megafaunal extinction is likely to have caused a cascade of changes that included increased fire, but only in some environments. We do not yet understand what environmental factors controlled the strength and nature of cascading effects of megafaunal extinction. This is an important topic for future research.

scholarly journals Has erosion globally increased? Long-term erosion rates as a function of climate derived from the impact crater inventory

2018 ◽  
Author(s):  
Stefan Hergarten ◽  
Thomas Kenkmann
Keyword(s):  
Time Scale ◽  
Impact Crater ◽  
Regional Effect ◽  
Tropical Zone ◽  
Erosion Rates ◽  
Continental Scale ◽  
River Loads ◽  
The Impact

Abstract. Worldwide erosion rates seem to have increased strongly since the beginning of the Quaternary, but there is still discussion about the role of glaciation as a potential driver and even whether the increase is real at all or an artefact due to losses in the long-term sedimentary record. In this study we derive estimates of average erosion rates on the time scale of some tens of million years from the terrestrial impact crater inventory. This approach is completely independent from all other methods to infer erosion rates such as river loads, preserved sediments, cosmogenic nuclides and thermochronometry. Our approach yields average erosion rates as a function of present-day topography and climate. The results confirm that topography accounts for the main part of the huge variation of erosion on Earth, but also identifies a significant systematic dependence on climate in contrast to several previous studies. We found a fivefold increase in erosional efficacy from the cold regimes to the tropical zone and that temperate and arid climates are very similar in this context. Combining our results to a worldwide mean erosion rate we found that erosion rates on the time scale of some tens of million years are at least as high as present-day rates and suggest that glaciation has a rather regional effect with a limited impact at the continental scale.

scholarly journals Effect of sowing density and nitrogen top-dress fertilisation on growth and yield of chia (Salvia hispanica L.) in a Mediterranean environment: first results

2015 ◽  
Vol 10 (3) ◽  
pp. 163 ◽  
Author(s):  
Rocco Bochicchio ◽  
Roberta Rossi ◽  
Rosanna Labella ◽  
Giovanni Bitella ◽  
Michele Perniola ◽  
...  
Keyword(s):  
Southern Italy ◽  
Plant Density ◽  
Fruit Production ◽  
Growth And Yield ◽  
Leaf Production ◽  
Salvia Hispanica ◽  
Area Index ◽  
First Results ◽  
Salvia Hispanica L ◽  
Set Up

The demand for sources of nutraceuticals has led to the rediscovery and diffusion of traditional crops such as chia (<em>Salvia hispanica</em> L.), whose leaves and fruits are rich in W3 fatty acids and anti-oxidants. Chia originates in Central America but it is rapidly expanding to new areas. A field experiment conducted at Atella in Basilicata (Southern Italy) was set up to test the response of chia to N top-dress fertilisation (0 and 20 kg ha<sup>–1</sup>) and to sowing density (D1=125, D2=25, D3=8 and D4=4 plants m<sup>–2</sup>) in a split-plot design with three replications. First results show maximum leaf area index values up to 7.1 and fresh vegetative biomass production at early flowering ranging between 50.87 (D4) and 59.71 (D1) t ha<sup>–1</sup>. Yield increased with plant density: a significantly (P&lt;0.01) higher production (398 kg ha<sup>–1</sup>) was reached in D1. N top-dressing had a detrimental effect on yield and corresponded to higher lodging and lower maturation percentage of seeds, though non-significant. Based on our first results it seems worthwhile to continue agronomical trials for chia in herbaceous systems of southern Italy for leaf production based on traditional genotypes, while fruit production might be pursued by adopting high sowing density and the search for longer-day genotypes.

scholarly journals EFFECT OF CRUDE OIL ON THE DEVELOPMENT OF WHITE MANGROVE SEEDLINGS (Avicennia germinans) IN THE NIGER DELTA, NIGERIA

2008 ◽  
Vol 30 (70/72) ◽  
Author(s):  
A. C. Chindah ◽  
S. A. Braide ◽  
J. O. Amakiri ◽  
J. Onokurhefe
Keyword(s):  
Crude Oil ◽  
Human Life ◽  
T Test ◽  
Avicennia Germinans ◽  
Growth Responses ◽  
Leaf Production ◽  
Wilcoxon Sign Rank ◽  
Mangrove Seedlings ◽  
Growth Attributes ◽  
The Impact

Crude oil is a complex hydrogen whose introduction into the may be hazardous to aquatic and human life, and consequently a threat to natural resources. The severity of the impact of crude oil depends on a variety of factors, including characteristics of the oil itself, natural conditions, such as water temperature and weather, and the sensitivities of receiving or biota. Consequently, various types of biological resources such as mangrove seedlings have different sensitivities to oil spills. The long term persistence of oil in the environment may cause defoliation and possibly death. Recruitment of seedlings into the oiled area may also be affected. This study is designed to evaluate the acute and chronic effects of crude oil (Bonny Light) on the growth performance of mangrove seedlings in a laboratory condition; monitoring critical plant growth attributes such as stem height and diameter, leaf length, width and numbers of leaves (leaf production), senescence and seedlings survival, for sixteen weeks. The study revealed that the mangrove seedlings responded differently in growth attributes with varying treatment. Evidence of crude oil effects were remarkably demonstrated between control and acute (Wilcoxon sign –rank t-test (1.0) > P (0.29)0.05 and chronic (Wilcoxon sign – rank, t-test (1.0) > p (0.47)0.05. The mangrove critical growth responses by mangrove seedlings as a result of the treatments were further explained by the cluster and correspondence analyses.

scholarly journals Foliar analysis in experimentally grown Lacatan bananas in relation to leaf production and bunch weight.

1962 ◽  
Vol 10 (2) ◽  
pp. 118-126 ◽  
Author(s):  
W.J. Brezowsky ◽  
J. Van Biesen
Keyword(s):  
Rainy Season ◽  
Foliar Analysis ◽  
Depressing Effect ◽  
Leaf Production ◽  
Positive Effect ◽  
Leaf N

Foliar analyses from October to April (the drier part of the year) showed a positive effect of an increased potash application on leaf K, and a depressing effect on leaf Mg. Both these effects were statistically insignificant just before and during the period when most of the plants started to shoot. There was no significant effect of increased N applications on leaf N, except in the early part of the rainy season. Increased K also had a significant effect on bunch weight, hand weight and the number of hands per stem.-Cameroons Develop. Corp. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Effects of Nitrogen Addition and Reproductive Effort on Nutrient Resorption of a Sand-Fixing Shrub

2020 ◽  
Vol 11 ◽  
Author(s):  
Lilong Wang ◽  
Yulin Li ◽  
Yulong Duan ◽  
Jie Lian ◽  
Yongqing Luo ◽  
...  
Keyword(s):  
Reproductive Effort ◽  
Fruit Production ◽  
Nutrient Resorption ◽  
N Recovery ◽  
N Addition ◽  
Resorption Efficiency ◽  
Temporal Separation ◽  
N Resorption ◽  
N Resorption Efficiency ◽  
Leaf N

Caragana microphylla is a sand-fixing leguminous shrub with strong resistance to drought, cold, and low soil fertility. As a result, it plays an essential role in combating desertification in northern China, but little is known about its nutrient budget. Nutrient resorption is a key process in plant nutrient conservation and has marked ecological implications for plant fitness and ecosystem nutrient cycling. We studied the effects of both nitrogen (N) addition and reproductive effort on leaf N resorption of C. microphylla in a temperate semi-arid sandy land in China. The results showed that sprouting of the early leaves from over-wintered buds employs a strategy for slow returns on nutrient investment with smaller specific leaf area (SLA) and higher N resorption efficiency, whereas the late leaves, which sprout from current-year buds, employ a strategy for quick returns on nutrient investment with higher SLA and lower N resorption efficiency. N addition significantly increased the N resorption efficiency from early leaves while exerting no impact on late leaves, suggesting that the increased N recovery from early leaves is done to sustain the high N demands of late leaves. Reproductive effort did not affect the N resorption from early or late leaves due to the temporal separation between fruit production and leaf senescence. Taken together, our results demonstrate that C. microphylla has evolved different investment strategies for leaf N in early and late leaves to conserve nutrients and facilitate its growth in desertified environments.

scholarly journals Fertilization the Omission One Test as Determination Limiting Factors for Maize Biomass (Zea mays L.)

2021 ◽  
Vol 4 (2) ◽  
pp. 94-105
Author(s):  
Koko Tampubolon ◽  
Bagus Fitra Azmi ◽  
Perdana Andriano Tamba ◽  
Ayu Widya Lestari ◽  
Kamaruddin Kamaruddin ◽  
...  
Keyword(s):  
Plant Height ◽  
Leaf Growth ◽  
Block Design ◽  
Relative Yield ◽  
Animal Husbandry ◽  
Dry Weight ◽  
Limiting Factors ◽  
Limiting Factor ◽  
Test Technique ◽  
The Impact

Introduction: The research was aimed to obtain information on the impact of omission one test fertilization as a determination limiting factors for the growth and biomass of maize in variety Bonanza F1. Materials and Methods: The research was located in the experimental field, Faculty of Agriculture and Animal Husbandry, Universitas Tjut Nyak Dhien, Medan from December 2020 until February 2021. The research was applied by Randomized Block Design in non-factorial through fertilization of omission one test that has been converted (urea : SP-36 : KCl = 0.75 : 0.50 : 0.125 g polybag-1). The treatment of this research include P0 = non-fertilization; P1= N+P+K; P2= P+K; P3= N+K; P4= N+P using three replications. The parameters include plant height, leaf growth, total fresh weight, total dry weight, and the percentage of relative yield then processed using ANOVA and continued with DMRT at 5% ± standard error with SPSS v.20 software. Results: Informed that the omission one test technique significantly improved all the characteristics of maize in the variety Bonanza F1. The highest increase in plant height was found in the N+P of 83.65%, meanwhile, the highest leaf and biomass growth characters were found in N+P+K, ranged of 50.00 to 177.81% and 487.60 to 507.37%, respectively. It was obtained that the limiting factor for the maize growth in variety Bonanza F1 was found in the un-fertilization of nitrogen.

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