Effects of N:P Ratio and Nutrient Level on the Competition between Invasive Alternanthera philoxeroides and Native Oenanthe javanica

2012 ◽  
Vol 534 ◽  
pp. 337-342 ◽  
Author(s):  
Rui Ying Chang ◽  
Ren Qing Wang ◽  
Yi Ran Zhang ◽  
Jian Liu
Keyword(s):  
N:P Ratio ◽  
Nutrient Supply ◽  
Physiological Traits ◽  
Alternanthera Philoxeroides ◽  
Nutrient Level ◽  
Total Biomass ◽  
High Nutrient ◽  
Morphological And Physiological Traits ◽  
Oenanthe Javanica ◽  
High Nutrient Supply

This study examined the effects of N:P ratio and nutrient level on the competition between invasive Alternanthera philoxeroides and native Oenanthe javanica in terms of morphological and physiological traits and the relative dominance index (RDI). In the experiment, A. philoxeroides was grown in mixture with O. javanica at three N:P supply ratios (1,10,100) combined with three levels of nutrient supply. The results suggested that the morphological and physiological traits of invasive and native species were both significantly affected by N:P ratio and nutrient supply level. The total biomass of both species was maximal under the treatment of lowest N:P ratio and highest nutrient supply, and A. philoxeroides had higher total biomass than O. javanica in every treatment. A. philoxeroides had higher plasticity than O. javanica on total biomass, R/S, SLA, which had sensitive response to the changing nutrient conditions. Meanwhile, the RDI of A. philoxeroides under high nutrient supply was higher than that under low nutrient supply, which showed that high nutrient supply could promote the invasion of A. philoxeroides while P-limitation (high N:P ratio) may prevent the successful invasion of A. philoxeroides under the lower nutrient supply.

scholarly journals Equatorial Pacific peak in biological production regulated by nutrient and upwelling during the late Pliocene/early Pleistocene cooling

2013 ◽  
Vol 10 (3) ◽  
pp. 5535-5554
Author(s):  
J. Etourneau ◽  
R. S. Robinson ◽  
P. Martinez ◽  
R. Schneider
Keyword(s):  
Nutrient Supply ◽  
Equatorial Pacific ◽  
Sea Surface ◽  
Early Pleistocene ◽  
High Latitudes ◽  
Export Production ◽  
Eastern Equatorial Pacific ◽  
Nutrient Consumption ◽  
High Nutrient ◽  
High Nutrient Supply

Abstract. The largest increase in export production in the eastern Pacific of the last 5.3 Myr (million years) occurred between 2.2 and 1.6 Myr, a time of major climatic and oceanographic reorganization in the region. Here, we investigate the causes of this event using reconstructions of export production, nutrient supply and oceanic conditions across the Pliocene-Pleistocene in the eastern equatorial Pacific (EEP) for the last 3.2 Myr. Our results indicate that the export production peak corresponds to a cold interval marked by high nutrient supply relative to consumption, as revealed by the low bulk sedimentary 15N/14N (δ15N) and alkenone-derived sea surface temperature (SST) values. This ~ 0.6 million years long episode of enhanced delivery of nutrients to the surface of the EEP was predominantly initiated through the upwelling of nutrient-enriched water sourced in high latitudes. In addition, this phenomenon was likely promoted by the regional intensification of upwelling in response to the development of intense Walker and Hadley atmospheric circulations. Increased nutrient consumption in the polar oceans and enhanced denitrification in the equatorial regions restrained nutrient supply and availability and terminated the high export production event.

Low soil temperature reduces the positive effects of high nutrient supply on the growth and biomass of white birch seedlings in ambient and elevated carbon dioxide concentrations

Botany ◽  
2009 ◽  
Vol 87 (10) ◽  
pp. 905-912 ◽  
Author(s):  
Titus Fondo Ambebe ◽  
Qing-Lai Dang ◽  
Jacob Marfo
Keyword(s):  
Carbon Dioxide ◽  
Soil Temperature ◽  
Nutrient Supply ◽  
Interactive Effects ◽  
Mass Ratio ◽  
White Birch ◽  
Stem Biomass ◽  
Leaf Mass Ratio ◽  
High Nutrient ◽  
High Nutrient Supply

To investigate the interactive effects of soil temperature (Tsoil) and nutrient supply on the responses of growth and biomass of white birch ( Betula papyrifera Marsh.) to atmospheric carbon dioxide concentration ([CO2]), seedlings were grown under two [CO2] (360 and 720 µmol·mol–1), three Tsoil (5, 15, and 25 °C initially, increased to 7, 17, and 27 °C one month later), and three nutrient regimes (Low: N–P–K = 4:1.8:3.3 mg·L–1; Intermediate: N–P–K = 80:35:66 mg·L–1; and High: N–P–K = 160:70:132 mg·L–1) for 4 months. Low Tsoil reduced leaf and total biomass at high nutrient supply and root biomass at intermediate and high nutrient supply. There were significant three-factor interactive effects on root collar diameter (RCD), stem biomass, and leaf mass ratio. Low Tsoil reduced RCD at high nutrient supply and stem biomass at intermediate and high nutrient supply in elevated [CO2] while intermediate and high Tsoil enhanced them. Values of leaf mass ratio were lowest at low Tsoil and low nutrient supply in elevated [CO2]. The effect of Tsoil was generally insignificant at low nutrient supply, but the responses of growth and biomass remained significantly higher under high than low nutrient supply at all Tsoil.

Sustained High Nutrient Supply As an Allelopathic Trigger between Periphytic Biofilm and Microcystis aeruginosa

2017 ◽  
Vol 51 (17) ◽  
pp. 9614-9623 ◽  
Author(s):  
Yonghong Wu ◽  
Jun Tang ◽  
Junzhuo Liu ◽  
Bruce Graham ◽  
Philip G. Kerr ◽  
...  
Keyword(s):  
Microcystis Aeruginosa ◽  
Nutrient Supply ◽  
High Nutrient ◽  
Periphytic Biofilm ◽  
High Nutrient Supply

scholarly journals Equatorial Pacific peak in biological production regulated by nutrient and upwelling during the late Pliocene/early Pleistocene cooling

2013 ◽  
Vol 10 (8) ◽  
pp. 5663-5670 ◽  
Author(s):  
J. Etourneau ◽  
R. S. Robinson ◽  
P. Martinez ◽  
R. Schneider
Keyword(s):  
Nutrient Supply ◽  
Equatorial Pacific ◽  
Sea Surface ◽  
Early Pleistocene ◽  
High Latitudes ◽  
Export Production ◽  
Eastern Equatorial Pacific ◽  
Nutrient Consumption ◽  
High Nutrient ◽  
High Nutrient Supply

Abstract. The largest increase in export production in the eastern Pacific of the last 5.3 Myr (million years) occurred between 2.2 and 1.6 Myr, a time of major climatic and oceanographic reorganization in the region. Here, we investigate the causes of this event using reconstructions of export production, nutrient supply and oceanic conditions across the Pliocene–Pleistocene in the eastern equatorial Pacific (EEP) for the last 3.2 Myr. Our results indicate that the export production peak corresponds to a cold interval marked by high nutrient supply relative to consumption, as revealed by the low bulk sedimentary 15N/14N (δ15N) and alkenone-derived sea surface temperature (SST) values. This ∼0.6 million year long episode of enhanced delivery of nutrients to the surface of the EEP was predominantly initiated through the upwelling of nutrient-enriched water sourced in high latitudes. In addition, this phenomenon was likely promoted by the regional intensification of upwelling in response to the development of intense Walker and Hadley atmospheric circulations. Increased nutrient consumption in the polar oceans and enhanced denitrification in the equatorial regions restrained nutrient supply and availability and terminated the high export production event.

Effects of High Nutrient Supply on the Growth of Seven Bamboo Species

2014 ◽  
Vol 16 (10) ◽  
pp. 1042-1057 ◽  
Author(s):  
Julien Piouceau ◽  
Grégory Bois ◽  
Frédéric Panfili ◽  
Matthieu Anastase ◽  
Laurent Dufossé ◽  
...  
Keyword(s):  
Nutrient Supply ◽  
Bamboo Species ◽  
High Nutrient ◽  
High Nutrient Supply

scholarly journals Tournaisian (Mississippian) brachiopods from the Mobarak Formation, North Iran

GeoArabia ◽  
2011 ◽  
Vol 16 (3) ◽  
pp. 129-192 ◽  
Author(s):  
Maryamnaz Bahrammanesh ◽  
Lucia Angiolini ◽  
Anselmo Alessandro Antonelli ◽  
Babak Aghababalou ◽  
Maurizio Gaetani
Keyword(s):  
Western Europe ◽  
Cold Water ◽  
Surface Current ◽  
High Energy ◽  
Nutrient Supply ◽  
Middle Part ◽  
Russian Platform ◽  
The Other ◽  
High Nutrient ◽  
High Nutrient Supply

ABSTRACT Following detailed stratigraphic work on the Mississippian marlstone and bioclastic limestone of the Mobarak Formation of the Alborz Mountains in North Iran, forty-eight of the most important brachiopod taxa are here systematically described and illustrated. The ranges of the taxa are given along the Abrendan and Simeh Kuh stratigraphic sections, located north of Damgham. The examined brachiopod species date the base of the Mobarak Formation to the Tournaisian, in absence of age-diagnostic foraminifers. Change in brachiopod settling preferences indicates a shift from high energy, shallow-water settings with high nutrient supply in the lower part of the formation to quieter, soft, but not soppy substrates, with lower nutrient supply in the middle part of the Mobarak Formation. Brachiopod occurrence is instead scanty at its top. The palaeobiogeographic affinity of the Tournaisian brachiopods from North Iran indicates a closer relationship to North America, Western Europe and the Russian Platform than to cold-water Australian faunas, confirming the affinity of the other biota of the Alborz Mountains. This can be explained by the occurrence of warm surface-current gyres widely distributing brachiopod larvae across the Palaeotethys Ocean, where North Iran as other peri-Gondwanan blocks acted as staging-posts.

The effects of nutrient variation and age on the resistance of three winter-dormant white birch species to mammalian herbivores

2004 ◽  
Vol 34 (11) ◽  
pp. 2230-2239 ◽  
Author(s):  
Jaana Laitinen ◽  
Matti Rousi ◽  
Jorma Tahvanainen ◽  
Heikki Henttonen ◽  
Jaakko Heinonen
Keyword(s):  
Betula Pendula ◽  
Nutrient Status ◽  
Nutrient Supply ◽  
Good Growth ◽  
White Birch ◽  
Resistance Response ◽  
Mammalian Herbivores ◽  
Nutrient Levels ◽  
High Nutrient ◽  
High Nutrient Supply

In this study, we investigated variation in the resistance of winter-dormant white birch species (Betula resinifera Britt., Betula pendula Roth, and Betula platyphylla Sukatchev var. japonica Hara) at different ontogenetic phases to mountain hares (Lepus timidus L.) and field voles (Microtus agrestis L.). The birches were grown for 4 years in outdoor pots and in a field experiment at different nutrient levels. The species differed in their overall levels of resistance to mountain hares and in their resistance responses at different nutrient levels. The exotic species, B. resinifera and B. platyphylla, were more resistant than the native B. pendula. Variation in resistance to voles between and within species at different fertilizer levels was less pronounced. The resistance response of white birches to hares seems to be related to their ontogeny, as well as to the nutrient status of the soil. At high nutrient supply, young birch seedlings achieve good growth and high resistance, with no tradeoff between growth and resistance, but the effect of fertilization on resistance stabilizes in aging trees. Before we can arrive at any general conclusions about the resistance responses of trees in variable environmental conditions, the effect of ontogeny must be considered, as well as differences between plant genotypes.

scholarly journals The Control of Tillering in the Barley Plant II. The Control of Tiller-Bud Growth During Ear Development

1963 ◽  
Vol 16 (2) ◽  
pp. 285 ◽  
Author(s):  
D Aspinall
Keyword(s):  
Considerable Increase ◽  
Nutrient Supply ◽  
Mineral Nutrient ◽  
Barley Plant ◽  
Grain Number ◽  
High Nutrient ◽  
Bud Growth ◽  
Nitrogen Contents ◽  
High Nutrient Supply ◽  
Tiller Bud

Tho intoraction between grain number and the level of mineral nutrient supply in the control of tiller-bud elongation has been examined in two varieties of barley (cv. Pil'oline, free tillering; cv. CI. 3576, restricted tillering). It was found in Pil'oline that the level of the nutrient supply did not alter the effect of the grains, although a considerable increase in tillering at all levels of grain removal resulted from an increase in the mineral nutrient supply. In CI. 3576, on the other hand, increasing the nutrient supply decreased the influence of the grains although it required an extremely high nutrient supply to completely suppress the grain effect. The hypothesis that tillering in this variety was primarily controlled by competition between the grains and WIer buds for a limited nutrient supply was supported by an examination of the nitrogen contents of the grains and emel'ging tillers.

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