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1

Adaptive significance of and factors affecting plasticity of biomass allocation and rhizome morphology: a case study of the clonal plant Scirpus planiculmis (Cyperaceae)

100%
Ning Y., Zhang Z. X., Cui L. J., Zou C. L.
Polish Journal of Ecology
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2014
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tom 62
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nr 1
In plants, biomass allocation and rhizome morphological plasticity reflect different strategies of adaptation to the environment. The aims of this study were to explore the patterns of allocation to different components of the belowground system, and to evaluate the effects of environmental factors on the plasticity of biomass allocation and rhizome morphology. We conducted a survey of the clonal plant, Scirpus planiculmis, in the Momoge wetland in northeastern China. Samples were collected at three sites. Site I is the washland of a seasonal lake. Site II is a permanent lake. Site III belongs to the bank of a recessive river. The average number of sampled plants was 686.25±91.61 per site. We determined the biomass of different plant parts (aboveground part, root, tuber, rhizome) and measured parameters of rhizome morphology (specific rhizome length, average rhizome diameter). Edaphic factors (soil moisture content, organic matter, available phosphorus, available potassium, pH, electrical conductivity) were included as environmental variables. Differences in biomass allocation patterns were analyzed and multiple regression analyses were used to construct a model. The results showed that the structure of the belowground system varied significantly among the three sites. (1) The tubers accounted for the largest share of biomass in plants at site I; (2) plants at site III showed significantly longer rhizomes than those of plants at site II, while the plants at site II showed larger rhizome diameter; (3) pH was the crucial factor affecting biomass allocation and rhizome morphology, and was negatively correlated with root biomass of S. planiculmis. Based on these results, we concluded that: (1) greater resource allocation to the storage organ (tuber) reflects a conservative strategy to avoid damage and to maintain the potential for recolonization in a frequently disturbed habitat; (2) the morphological plasticity of the rhizome increases the ability of the clone to acquire resources. Shorter rhizomes enable rapid colonization of the habitat and efficient resource use under strong competition pressure, while longer rhizomes are useful to explore new habitats when local resources are insufficient. Our results suggest that ecological niche of S. planiculmis should be reconsidered. It may be more appropriate to classify S. planiculmis as a facultative salt-alkali plant, although a degree of tolerance to salinity and alkalinity is important for the initial formation of a population.
2

Production and allocation of biomass and radiation use efficiency in four clones of Salix viminalis L.

84%
Borek R.
Polish Journal of Agronomy
|
2009
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nr 01
3

Invariant allometric relationship between above- and below-ground biomass along a moisture gradient in North - West China

84%
Cheng D. L., Wang G.-X., Tang Q.-L., Li T., Zhong Q.-L.
Polish Journal of Ecology
|
2009
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tom 57
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nr 4
669-675
Biomass allocation pattern is an important plant characteristic which influences how plants respond to abiotic and biotic heterogeneity. Prior studies indicate that above-ground biomass scales nearly isometrically with respect to below-ground biomass regardless of environment or phyletic affinity. However, such rule has been mostly tested with data on trees and usually without drought stress. Given the importance of this predicted relationship, it should be evaluated for a wider range of species and environmental conditions. Variations of the above- and belowground biomass (MA and MR, respectively) were determined from five sites in north-west China, which compose a natural moisture gradient (aridity index ranging from 0.95 to 1.98). Model Type II regression protocols were used to compare the numerical values of MA vs MR scaling exponents (i.e. slopes of log-log linear relationships). The resulting five scaling exponents were indistinguishable and had a similar, nearly isometric slope (i.e. MA ∞ MR ͌ ¹‧⁰). Significant variation was observed in the Y-intercepts of the five regression curves, because of the absolute differences in MA or MR. These results support prior allometric theory, which reveals an isometric relationship between above- and below-ground biomass, and may provide a suitable method to estimate the regional below-ground biomass based on the direct aboveground measurements.
4

Biomass allocation, compensatory growth and internal C/N balance of Lolium perenne in response to defoliation and light treatments

84%
Wang L., Wang J., Liu W., Gan Y., Wu Y.
Polish Journal of Ecology
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2016
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tom 64
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nr 4
Light environments can have a considerable influence on how plants respond to defoliation through influencing the biomass allocation patterns and internal C/N ratio. Seedlings of Lolium perenne, a common perennial grass species, were grown for eight weeks under three different light environments (natural light, red light and shading) and two different defoliation treatments (no defoliation versus 50% aboveground biomass removal). This study was conducted to examine (1) the effects of light regimes and defoliation on biomass accumulation, biomass allocation and internal C/N ratio status in plants; (2) how the light regimes influence the pattern of compensatory growth after defoliation; and (3) the relationship between compensatory growth and the internal C/N ratio status. We found that red light altered the shoot-to-root allometry, enhanced the leaf C concentrations and induced N deficiency. By contrast, the leaf N concentrations of L. perenne were greater during shading treatment, which simultaneously enhanced shoot growth and stopped root growth. Under defoliation, red light increased shoot growth, not at the expense of root growth, which was not the same as in natural light and shading treatment. Moreover, regardless of the unclipped (no defoliation) and defoliation conditions, the L. perenne biomass partitioning between roots and shoots was significantly correlated with the leaf N concentrations and C/N ratio, indicating that allometric biomass allocation can be largely modulated by signals related to the C and N status of the plants. These results demonstrated that the leaf C and N status would be an appropriate indicator of compensatory growth after defoliation.
5

Allometric partitioning theory versus optimal partitioning theory: the adjustment of biomass allocation and internal C-N balance to shading and nitrogen addition in Fritillaria unibracteata (Liliaceae)

84%
Guo H., Xu B., Wu Y., Shi F., Wu C., Wu N.
Polish Journal of Ecology
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2016
|
tom 64
|
nr 2
Fritillaria unibracteata is a classic perennial alpine herb. In this study, we examined it's responses to shading (SH) and nitrogen addition (NA), as well as its correlation with internal C-N balance to detect how it adjusted to the changes of habitat conditions. Randomized block experiment was carried out in the field in Chuanbeimu Research Station in Songpan County, Sichuan Province, China (32°09′54″N, 103°38′36″E, altitude 3300 m a.s.l.). Two growing seasons after NA and SH, Fritillaria unibracteata's total plant biomass decreased significantly, with the proportion of biomass allocated to aboveground significantly increased. In addition, in this study, under both SH and NA treatments, Fritillaria unibracteata increased its biomass allocation to above-ground, which consisted with optimal partitioning theory. Moreover, Fritillaria unibracteata's biomass allocation was significantly correlated with its internal C-N status, regardless of nitrogen and light condition. We conclude that Fritillaria unibracteata optimizes its biomass allocation between root and shoot by adjusting its internal C-N balance, which would not be changed by the specialized resource storage organ-bulb.
6

Life history strategy influences biomass allocation in response to limiting nutrients and water in an arid system

84%
Mao W., Allington G., Li Y.-L., Zhang T.-H., Zhao X.-Y., Wang S.-K.
Polish Journal of Ecology
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2012
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tom 60
|
nr 3
The optimal partitioning theory (OPT) predicts that a plant should allocate relatively more biomass to the organs that acquire the most limiting resource. However, variation in biomass allocation among plant parts can also occur as a plant grows in size. As an alternative approach, allometric biomass partitioning theory (APT) asserts that plants should trade off their biomass between roots, stems and leaves, and this approach can minimize bias when comparing biomass allocation patterns by accounting for plant size in the analysis. We analyzed the biomass allocation strategy of the two species: annual Setaria viridis (L.) Beauv and perennial Pennisetum centrasiaticum Tzvel from the Horqin Sandy Land of northern China by treating them with different availabilities of soil nutrient and water (added in summer and winter), and hypothesized that the two species have different patterns of biomass allocation strategy in response to different soil water content and soil nitrogen content. After taking plant size into account, the biomass allocation strategy of S. viridis and P. centrasiaticum differed in response to nitrogen and water; leaves and root:shoot ratio (RTS) of S. viridis were “true” in response to various soil nitrogen contents. The plasticity of roots was also “true” in response to fluctuation in soil water content. However, P. centrasiaticum showed a different pattern with no shift of biomass allocation strategy in response to nitrogen and water. Adjustment in organs biomass allocation pattern of S. viridis in response to nitrogen and water limitation was dramatic, this suggested that S. viridis support optimal partitioning theory (OPT). P. centrasiaticum has better tolerance to varied environments and more likely support the allometric biomass partitioning theory (APT), this characteristic may allow P. centrasiaticum to keep dominance in fragile habitats.
7
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Biomass dynamics in young silver birch stands on post-agricultural lands in Central Poland

84%
Zasada M., Bijak S., Bronisz K., Bronisz A., Gaweda T.
Drewno. Prace Naukowe. Doniesienia. Komunikaty
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2014
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tom 57
|
nr 192
The paper analyses the production and allocation of biomass in young, spontaneoussilver birch afforestation occurring on post-agricultural lands in the Mazowszeregion (central Poland). We investigated 114 sample plots of age varying from 1 to 19 years. During the first 15 years after their establishment on abandoned farmland, the naturally regenerated silver birch stands produced on average approximately 75 tons of dry biomass per hectare. The major (50–70%) part of this biomass was stored in the tree stems and this share increased with age. The fractions of biomass in the foliage and roots decreased over time, while the share of biomass in the branches remained rather constant. The significant age-dependency of the allometric relationships suggested the need to use age-sensitive biomass expansion factors to estimate the biomass from the stem volume.
8

Generative reproduction in Rumex confertus Willd. populations

84%
Stosik T.
Electronic Journal of Polish Agricultural Universities. Series Biology
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2007
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tom 10
|
nr 4
9

Growth, biomass allocation and nutrients accumulation in needles of Abies alba seedlings growing three years on humus from different forest sites

84%
Robakowski P., Komisarek J., Nowinski M., Bulaj B.
Acta Physiologiae Plantarum
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2007
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tom 29
|
nr 1 Suppl.
10
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Content available

The effect of Puccinia komarovii Tranzsch. infection on characters of Impatiens parviflora Dc. in Galio Sylvatici-Carpinetum [R. Tx. 1937] Oberd. 1957 forest association

84%
Piskorz R., Klimko M.
Acta Societatis Botanicorum Poloniae
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2006
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tom 75
|
nr 1
51-59
The aim of the present study was to determine how internal diversity of oak-hornbeam forest modifies the course and effects of infestation of small-flowered balsam (Impatiens parviflora) with rust Puccinia komarovii. The study investigated the effect of the disease on the demography of the population, and the habit and biomass allocation of the infested specimens, as well as the initiation of non-specific defense mechanisms. It was shown that: 1) the percentage of infected specimens was independent of the undergrowth-coverage rate and of the I. parviflora density; 2) infected populations differ from healthy ones in the seasonal dynamics of abundance changes; 3) high mortality is observed as early as May and the first part of June, i.e. it pertains to specimens, which did not begin reproduction; 4) the presence of infection and its intensity stimulate the growth of the stem and the hypocotyl; 5) fresh weight of infected specimens is by almost 30% lower in comparison to the weight of uninfected plants; the weight of badly infected plants decreases by 20% in comparison to the less severely infected balsam plants; the weight of generative organs drops most significantly, even by over 50%; 6) biomass allocation does not fluctuate considerably; 7) reproduction effort expressed by the ratio of the weight of fruits (or only seeds) to the total biomass shows a distinct downward trend; 8) the environmental factor does not affect the force of defense mechanisms, the strength of biochemical response of diseased plants depends on the degree of their infestation.
11
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Reproductive effort as an element of life strategy of Lythrum salicaria L. populations

84%
Czarnecka B., Franczak M., Nowak K.
Acta Agrobotanica
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2007
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tom 60
|
nr 2
The aim of the study was to compare some life strategy traits of individuals of Purple Loosestrife Lythrum salicaria within three meadow populations existing under various habitat conditions. The study attempted to answer the following questions: Do different habitat conditions affect the biomass allocation between particular organs of individuals? Can the individuals belonging to different populations of the same species realise their own unique reproductive strategy, in other words, can their reproductive effort represent various levels? In the case of L. salicaria the reproductive effort, measured by the participation of inflorescence biomass in the biomass of aboveground parts of genets, exhibits similar values (14.2-15.1%) in all the study populations, despite their habitat conditions. This fact proves that at the population level, the reproductive effort is relatively stable. Great differences are visible in the case of particular individuals within each of the populations. Specific genets in a population, depending on the habitat microstructure and the biotic relations with other individuals both of their own and other species, may realise their own reproductive strategies, being a part of their life strategies.
12

Variation of sexual and clonal reproduction in Eremosparton songoricum (Litv.) (Fabaceae) on drought in arid regions: an experimental approach

67%
Wang J.-C., Shi X., Yin L.-K., Zhang D.-Y.
Polish Journal of Ecology
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2012
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tom 60
|
nr 1
Clonal plants combine sexual and clonal reproduction, which contribute differently to plant fitness. We investigated the consequence of natural selection on the two reproductive modes and the ecological factors that affect the reproductive modes of Eremosparton songoricum (Litv.) Vass. in order to understand the reproductive strategies of a clonal plant and the relationship between sexual and clonal reproduction. Morphological characteristics and biomass allocation patterns were m easured and compared at the clonal fragment level in two natural populations (riverside population A and hinterland population B) in the Gurbantunggut Desert, China. The flowering plant ratio, inflorescence number per plant, flower number per raceme, fruit number, mass of 100 seeds, root biomass, fruit biomass and ramet height were significantly higher, whereas fruit set, ramet density, rhizome biomass and length, and root number were significantly lower, in population A compared with those in population B. We estimated that the importance of clonal reproduction varies in two populations of E. songoricum, and the investment adjustment in the two reproductive modes may be based on cost required for each new plant to generate the more survival progeny in the plant life time.
13
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Content available

Fine roots biomass and morphology in a chronosequence of young Pinus sylvestris stands growing on a reclaimed lignite mine spoil heap

67%
Jagodzinski A. M., Kalucka I.
Dendrobiology
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2010
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tom 64
The morphology of fine roots ( 2 mm diameter) as well as fine and coarse root biomass was investigated in a chronosequence consisting of 6-, 9-, 11-, 15-, 17- and 20-year-old Scots pine (Pinus sylvestris) stands growing on a reclaimed lignite mine spoil heap. Core method of destructive root sampling was used to establish whether root morphology and biomass varied with stand age in the upper 20 cm of soil. Fine root biomass ranged from 0.78 to 3.11 Mg ha-1, coarse root biomass ranged from 0.82 to 2.74 Mg ha-1, whereas root necromass ranged from 1.03 Mg ha-1 to 2.87 Mg ha-1 in the chronosequence studied. Fine root diameter as well as length, projected area, and surface area expressed per unit area increased significantly with stand age. Moreover, our study revealed that when stand age increases, specific fine root biomass increases, whereas specific root length and area decreases. The results support our hypothesis that stand age has an effect on standing fine root biomass and morphology.
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