Effects of water depth and substrate type on growth dynamics and biomass allocation of Oryza rufipogon

In the greenhouse, we investigated the growth and biomass allocation of three juvenile wetland species ( Carex tribuloides Wahl., Phalaris arundinacea L., and Rumex orbiculatus Gray) under three different water depths (–4, 0, and +2 cm relative to the soil surface), three N:P supply ratios (1:30, 1:1, 30:1), and two mycorrhizal inoculant treatments (arbuscular mycorrhizal (AM) fungi present, absent). After 6 weeks, the plants were harvested, separated to above- and below-ground parts, oven-dried, and weighed. The mycorrhizal inoculant significantly increased plant growth and reduced root:shoot ratios. At an N:P supply ratio of 30:1, plants with AM fungi had significantly greater biomass than those plants without AM fungi. However, at 1:1 N:P supply ratio, plants without AM fungi had greater biomass. Plants without AM fungi had higher root:shoot ratios at 0 and –4 cm water depth than plants with AM fungi. In general, C. tribuloides had the lowest growth, and unlike P. arundinacea and R. orbiculatus, was not affected by the water depth treatment. Growth of the wetland plants was limited more by nitrogen than by phosphorus. Our results suggest that at high N:P nutrient supply ratios and non-flooded conditions the growth of wetland seedlings can benefit by being inoculated with AM fungi.

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Rethinking root-shoot growth dynamics

10.1101/2020.06.29.177824 ◽

2020 ◽

Author(s):

David Robinson

Keyword(s):

Growth Rate ◽

Plant Growth ◽

Biomass Allocation ◽

Plant Biomass ◽

Wide Spectrum ◽

Growth Dynamics ◽

Adaptive Allocation ◽

Physiological Properties ◽

Whole Plant ◽

Rates Of Growth

AbstractUsing a simple plant growth model based on the logistic equation I re-evaluate how biomass allocation between roots and shoots articulates dynamically with the rate of whole-plant biomass production. Defined by parameters reflecting lumped physiological properties, the model constrains roots and shoots to grow sigmoidally over time. From those temporal patterns detailed trajectories of allocation and growth rate are reconstructed. Sigmoid growth trajectories of roots and shoots are incompatible with the dominant ‘functional equilibrium’ model of adaptive allocation and growth often used to explain plants’ responses to nutrient shortage and defoliation. Anything that changes the differential rates of growth between roots and shoots will automatically change allocation and, unavoidably, change whole-plant growth rate. Biomass allocation and whole-plant growth rate are not independent traits. Allocation and growth rate have no unique relationship to one another but can vary across a wide spectrum of possible relationships. When root-shoot allocation seems to respond to the environment it is likely to be a secondary illusory consequence of other primary responses such as localised root proliferation in soil or leaf expansion within canopy gaps. Changes in root-shoot allocation cannot themselves compensate directly for an impairment of growth rate caused by an external factor such as nutrient shortage or defoliation; therefore, such changes cannot be ‘adaptive’.‘The reasons are so simple they often escape notice.’ (James 2012, p. 6).

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Assessing Habitat Suitability for Native and Alien Freshwater Mussels in the River Waal (the Netherlands), Using Hydroacoustics and Species Sensitivity Distributions

Environmental Modeling & Assessment ◽

10.1007/s10666-021-09776-4 ◽

2021 ◽

Author(s):

N. Y. Flores ◽

F. P. L. Collas ◽

K. Mehler ◽

M. M. Schoor ◽

C. K. Feld ◽

...

Keyword(s):

Flow Velocity ◽

Water Depth ◽

Habitat Suitability ◽

Future Research ◽

Suitable Habitat ◽

Substrate Type ◽

Species Sensitivity ◽

Mussel Species ◽

Type Water ◽

Species Sensitivity Distributions

AbstractLongitudinal training dams (LTDs) in the river Waal are novel river training structures that protect the littoral zone from the adverse effects of navigation providing new habitats for riverine macroinvertebrates. In order to inform river management and to better understand their ecological value for native and alien mussel species, it is important to assess the habitat suitability of the protected LTD shore channels. We applied spatial hydroacoustics surveys consisting of side-scan sonar (SSS) and acoustic Doppler current profiler (ADCP) of the substrate type, water depth and flow velocity in three shore channels in combination with species sensitivity distributions (SSDs) to predict habitat suitability for native and alien mussel species. SSDs allowed for the prediction of habitat suitability as a potentially occurring fraction (POF) of a species pool. High substrate type, water depth, and near-bottom flow velocity POFs were found for ≥ 70%, 100%, and 4–51% of the total shore channel area, respectively, suggesting that shore channels provide suitable habitat for both native and alien mussel species. To enhance the shore channels as habitat for native mussel species, we recommend increasing shallow areas dominated by fine (silt/clay) and sand substrate types with low near-bottom flow velocities (near 0 m/s). In contrast, the total area of hard substrate (e.g., boulders) in the shore channels should be reduced as it strongly favored invasive alien mussel species in our study. Future research should include additional abiotic parameters to enhance the habitat suitability predictions and compare the results for different riverine habitats.

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Growth dynamics,biomass allocation and ecological adaptation inCeratocarpus arenariusL.

Acta Ecologica Sinica ◽

10.5846/stxb201105250689 ◽

2012 ◽

Vol 32 (11) ◽

pp. 3352-3358 ◽

Cited By ~ 1

Author(s):

全杜娟 QUAN Dujuan ◽

魏岩 WEI Yan ◽

周晓青 ZHOU Xiaoqing ◽

严成 YAN Cheng

Keyword(s):

Biomass Allocation ◽

Growth Dynamics ◽

Ecological Adaptation

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Occurrence of Soft and Hard Corals at Igang Bay and Villa Corazon, Nueva Valencia, Guimaras, Philippines

JPAIR Multidisciplinary Research ◽

10.7719/jpair.v7i1.155 ◽

2012 ◽

Vol 7 (1) ◽

Author(s):

Melchor Magramo ◽

Mary Mar Esmaña ◽

June Raymond Peter Flores ◽

Marlon Terunez

Keyword(s):

Water Depth ◽

Environmental Conditions ◽

Soft Corals ◽

Substrate Type ◽

Anatomical Features ◽

Structural Composition ◽

A Value ◽

Physico Chemical ◽

Sampling Points ◽

Chemical Conditions

The distribution of soft and hard corals is due to prevailing environmental conditions, coral anatomical features and structural composition and presence or absence of predators and competitors. The study determined the occurrence of soft and hard corals in Igang Bay, Nueva Valencia, Guimaras, Philippines. Ocular survey was conducted at front beach of Villa Igang and transect – quadrat sampling was carried out. . The results showed that soft corals found in Igang Bay include the genera Lobophytum, Radianthus, Sarcophyton, Sinularia and Xenia and hard corals include those that belong to Acropora, Coeloseris, Coscinaraea, Favia, Favites, Fungia, Lonophyllia, Millepora, Montipora and Porites genera. Hard corals had a greater cover with a total of 38.94% while soft corals had 3.33%. In each transect, hard corals occupied more space than soft corals. There were 6 colonies for hard corals and none for soft corals. Physico – chemical conditions, particularly the salinity did not vary between three sampling points with a value of 29 ppt. and the temperature between surface and bottom had an average of 31°C and 31.7°C.The water depth ranged from 0.9 to 1.1 meters. Generally, the substrate type was rocky and sandy with presence of some coral rubbles in some portions along the transect lines. Keywords – hard corals, soft corals, salinity, temperature, Igang Bay

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The blackflies (Diptera: Simuliidae) of insular Newfoundland. III. Factors affecting the distribution and migration of larval simuliids in small streams on the Avalon Peninsula

Canadian Journal of Zoology ◽

10.1139/z75-015 ◽

1975 ◽

Vol 53 (2) ◽

pp. 114-123 ◽

Cited By ~ 6

Author(s):

David J. Lewis ◽

Gordon F. Bennett

Keyword(s):

Population Dynamics ◽

Chemical Composition ◽

Water Depth ◽

Current Velocity ◽

Substrate Type ◽

Factors Affecting ◽

Small Streams ◽

And Migration ◽

Avalon Peninsula ◽

Significant Factors

Factors affecting the population dynamics, distribution, and migration of nine species of simuliid larvae in a complex of small streams on the Avalon Peninsula, Newfoundland, were studied. The most significant factors affecting the distribution and migration of simuliid larvae were current velocity, substrate type, and water depth; temperature, light, chemical composition of the water, and parasites were found to be of little or no significance.

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Effects of water depth on clonal characteristics and biomass allocation of Halophila ovalis (Hydrocharitaceae)

Journal of Plant Ecology ◽

10.1093/jpe/rtq038 ◽

2011 ◽

Vol 4 (4) ◽

pp. 283-291 ◽

Cited By ~ 8

Author(s):

N.-N. Xu ◽

X. Tong ◽

P.-K. E. Tsang ◽

H. Deng ◽

X.-Y. Chen

Keyword(s):

Biomass Allocation ◽

Water Depth ◽

Halophila Ovalis

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Vegetation of the aquatic and marshland habitats in the Orava region, including the first records of Potametum alpini, Potametum zizii and Ranunculo-Juncetum bulbosi in the territory of Slovakia

Biologia ◽

10.2478/s11756-011-0060-z ◽

2011 ◽

Vol 66 (4) ◽

Cited By ~ 4

Author(s):

Richard Hrivnák ◽

Judita Kochjarová ◽

Helena Oťaheľová

Keyword(s):

Plant Communities ◽

Water Depth ◽

Marsh Plant ◽

Substrate Type ◽

Indicator Values ◽

Ecological Gradient ◽

Type Conductivity ◽

Phytosociological Relevés ◽

Dominance Principle ◽

Marshland Habitats

AbstractThe vegetation of the aquatic and marshland habitats of the Orava region (north of Slovakia) was studied in 2009, using traditional phytosociological methods. Sixteen aquatic and eighteen marsh plant communities were described within 96 phytosociological relevés by using TWINSPAN with the application of the dominance principle. Three associations, Potametum alpini, Potametum zizii and Ranunculo-Juncetum bulbosi, were found as new communities for Slovakia. Myriophylletum verticillati, Potametum nodosi, Potametum graminei and Alisma gramineum community were recorded in the northernmost localities in Slovakia. Among marsh communities, Calletum palustris is very rare, both in the Orava region and in Slovakia as a whole. According to Ellenberg’s indicator values (EIV), moisture was evaluated as the main ecological gradient. Plant communities are ordered along the first Detrended Correspodence Analysis (DCA) axis in a typical hydroseries (Potametea → Lemnetea → Phragmition communis → Phalaridion arundinaceae, Oenanthion aquaticae and Sparganio-Glycerion → Magnocaricion elatae). The second DCA axis was most correlated with EIV for nutrients. Among the five directly measured ecological characteristics (temperature, pH and conductivity of water, water depth, and substrate type), conductivity of water (0.44, P < 0.01) and substrate type (0.32, P < 0.05) were the statistically significant variables explaining the variability along the first DCA axis.

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Clothing the Emperor: Dynamic Root–Shoot Allocation Trajectories in Relation to Whole-Plant Growth Rate and in Response to Temperature

Plants ◽

10.3390/plants8070212 ◽

2019 ◽

Vol 8 (7) ◽

pp. 212

Author(s):

David Robinson ◽

John Henry Peterkin

Keyword(s):

Growth Rate ◽

Plant Growth ◽

Biomass Allocation ◽

Growth Dynamics ◽

Maximum Size ◽

Environmental Drivers ◽

Shoot Biomass ◽

Root Mass ◽

Whole Plant ◽

Mass Fractions

We quantified how root–shoot biomass allocation and whole-plant growth rate co-varied ontogenetically in contrasting species in response to cooling. Seven grass and four forb species were grown for 56 days in hydroponics. Growth was measured repeatedly before and after day/night temperatures were reduced at 28 days from 20 °C/15 °C to 10 °C/5 °C; controls remained unchanged. Sigmoid trajectories of root and shoot growth were reconstructed from the experimental data to derive continuous whole-plant relative growth rates (RGRs) and root mass fractions (RMFs). Root mass fractions in cooled plants generally increased, but this originated from unexpected and previously uncharacterised differences in response among species. Root mass fraction and RGR co-trajectories were idiosyncratic in controls and cooled plants. The RGR–RMF co-trajectories responded to cooling in grasses, but not forbs. The RMF responses of stress-tolerant grasses were predictably weak but projected to eventually out-respond faster-growing species. Sigmoid growth constrains biomass allocation. Only when neither root nor shoot biomass is near-maximal can biomass allocation respond to environmental drivers. Near maximum size, plants cannot adjust RMF, which then reflects net above- and belowground productivities. Ontogenetic biomass allocations are not equivalent to those based on interspecific surveys, especially in mature vegetation. This reinforces the importance of measuring temporal growth dynamics, and not relying on “snapshot” comparisons to infer the functional significance of root–shoot allocation.

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