Seed Bank Dynamics of Three Co-Occurring Banksias in South Coastal Western Australia: the Role of Plant Age, Cockatoos, Senescence and Interfire Establishment.

1991 ◽  
Vol 39 (4) ◽  
pp. 385 ◽  
Author(s):  
ETF Witkowski ◽  
BB Lamont ◽  
SJ Connell
Keyword(s):  
Western Australia ◽  
Seed Bank ◽  
Quadratic Function ◽  
Seed Storage ◽  
Plant Age ◽  
The Other ◽  
Age Cohorts ◽  
Seed Bank Dynamics ◽  
Order Of Magnitude

Seed bank dynamics of three co-occurring, non-sprouting Banksia species (B. baxteri, B. speciosa and B. coccinea) in patch-burnt scrub-heath (aged 10 and 21 years) were studied in the southern sandplains of Western Australia. In the younger plants, canopy seed storage was highest in B. coccinea. However, 21-year-old B. coccinea stored an order of magnitude fewer seeds than the other species and no more than young B. coccinea. Seed storage per year increased exponentially with plant age in B. speciosa and B. baxteri, whereas a quadratic function, peaking at 16 years, best described seed storage in B. Coccinea. Degree of serotiny was lowest in B. coccinea. Seed abortion did not vary between age cohorts but was highest in B. coccinea. Granivory ranged from 18 to 42% and was highest in the older plants and in B. baxteri. Cockatoos removed about 20% of cones in B. baxteri and B. coccinea and 10% in B. speciosa. Experimental cone removal accelerated follicle opening, especially in B. coccinea, irrespective of whether cones were placed on the ground (simulating cockatoo removal) or reattached to the plant (simulating plant death). Half the 21-year-old B. coccinea were dead and the remainder were considered senescent, as most branches showed dieback and cone fertility had fallen to 8%. Death of the other species was negligible, with cone fertility rising to a mean of 45% (B. speciosa) and 66% (B. baxteri). Interfire establishment was significant only in B. coccinea. The build-up of a viable seed bank with time occurred at a slower rate than for non-sprouting banksias in the northern sandplains.

Analysis of seed-bank data confirms suitability of international seed-storage standards for the Australian flora

2007 ◽  
Vol 55 (1) ◽  
pp. 18 ◽  
Author(s):  
Andrew D. Crawford ◽  
Kathryn J. Steadman ◽  
Julie A. Plummer ◽  
Anne Cochrane ◽  
Robin J. Probert
Keyword(s):  
Western Australia ◽  
Seed Bank ◽  
Seed Storage ◽  
Storage Conditions ◽  
International Standards ◽  
Australian Flora ◽  
Western Australian

The suitability of applying international standards for long-term seed storage to the Australian flora was examined by reviewing seed-storage data from the Western Australian Threatened Flora Seed Centre. The 375 collections examined represented 176 taxa from 44 genera and 16 families. A high proportion of collections, representative of some of the most common genera in Australia, maintained viability in the short (<5 years) and medium (5–12 years) term. Declines in germination were evident for a small number of collections, representing 10 taxa, stored for 5–12 years. However, many of the declines were collection-specific and other collections of the same taxon did not decline. Five taxa showing germination declines were represented by a single collection so it was not possible to determine whether the germination decline was directly related to the taxa, storage conditions or to other factors. Only the closely related Stylidium coroniforme and S. amabile exhibited germination declines in all collections, but cut tests of seeds remaining from germination testing indicated that viability of the collections had not declined, just the proportion to germinate; for these species a change in germination conditions is a more likely explanation for the reduction in germination. The results illustrate the successful application of these seed-storage standards to threatened flora in Western Australia and highlight their suitability for the Australian flora.

scholarly journals Seed bank dynamics: the role of fungal pathogens and climate change

2000 ◽  
Vol 14 (3) ◽  
pp. 293-299 ◽  
Author(s):  
M. R. Leishman ◽  
G. J. Masters ◽  
I. P. Clarke ◽  
V. K. Brown
Keyword(s):  
Climate Change ◽  
Seed Bank ◽  
Fungal Pathogens ◽  
Seed Bank Dynamics

scholarly journals Seed bank dynamics of an invasive alien species, Helianthus annuus L.

2020 ◽  
Vol 13 (3) ◽  
pp. 313-322
Author(s):  
Alejandro Presotto ◽  
Fernando Hernández ◽  
Mauricio Casquero ◽  
Roman Vercellino ◽  
Claudio Pandolfo ◽  
...  
Keyword(s):  
Helianthus Annuus ◽  
Seed Bank ◽  
Seedling Emergence ◽  
Seed Banks ◽  
First Year ◽  
Seed Burial ◽  
Wild Sunflower ◽  
Seed Persistence ◽  
Seed Bank Dynamics

Abstract Aims The ability to form persistent seed banks is one of the best predictors of species’ potential to establish in new ranges. Wild sunflower is native to North America where the formation of persistent seed banks is promoted by disturbance and it plays a key role on the establishment and persistence of native populations. However, the role of the seed banks on the establishment and persistence of invasive populations has not been studied. Here, we evaluated the role of seed bank and disturbance on the establishment and fitness, and seed persistence in the soil in several sunflower biotypes collected in ruderal (wild Helianthus annuus) and agrestal (natural crop–wild hybrid) habitats of Argentina as well as volunteer populations (progeny of commercial cultivars). Methods In a seed-bank experiment, we evaluated emergence, survival to reproduction, survival of emerged seedlings, inflorescences per plant and per plot under disturbed and undisturbed conditions over 2 years; in a seed-burial experiment, we evaluated seed persistence in the soil over four springs (6, 18, 30 and 42 months). Important Findings Overall, seedling emergence was early in the growing season (during winter), and it was promoted by disturbance, especially in the first year. Despite this, the number of inflorescences per plot was similar under both conditions, especially in ruderals. In the second year, emergence from the seed bank was much lower, but the survival rate was higher. In the seed-burial experiment, genetic differences were observed but seeds of ruderals and agrestals persisted up to 42 months while seeds of the volunteer did not persist longer than 6 months. The agrestal biotype showed an intermediate behavior between ruderals and volunteers in both experiments. Our findings showed that wild and crop–wild sunflower can form persistent seed banks outside its native range and that disturbance may facilitate its establishment in new areas.

Seed bank dynamics of a serotinus, fire-sensitive Banksia species

1988 ◽  
Vol 36 (2) ◽  
pp. 193 ◽  
Author(s):  
BB Lamont ◽  
MJ Barker
Keyword(s):  
Western Australia ◽  
Seed Bank ◽  
Small Area ◽  
Substantial Proportion ◽  
Seed Abortion ◽  
Viable Seed ◽  
Seed Availability ◽  
Seed Bank Dynamics ◽  
Viable Seeds ◽  
Season Of Burn

Banksia burdettii is a locally abundant shrub restricted to a small area in south-western Australia. At the study site, the canopy-stored seed bank built up exponentially with plant age to yield a mean of 830 viable seeds per plant from about 212 000 ovules produced over 16 years. Seed availability was the net result per year of number of flower heads, extent of head removal by cockatoos, number of florets per head and number of fruits (follicles) per floret in the production phase and the extent of seed abortion, insect granivory, seed senescence and spontaneous seed release in the mortality phase. Plants are killed by fire and a substantial proportion of cones was consumed by a hot fire. Up to 87% of viable seed may survive and be released within 100 days of a fire, depending on intensity and season of burn. Plants which died in the absence of fire released little viable seed subsequently, while the remainder were consumed when fire occurred. Comparison of 25 reproductive attributes between B. burdettii and another two Banksia species occurring in the vicinity indicated that it has much in common with these serotinous, non-sprouters. Although viable canopy-stored seeds account for few of the original ovules, reproductive inefficiency, once a fire interval of 10 years is exceeded, cannot explain the restricted distribution of this species.

scholarly journals Estimating seed bank accumulation and dynamics in three obligate-seeder Proteaceae species

2014 ◽  
Author(s):  
Meaghan E. Jenkins ◽  
David Morrison ◽  
Tony D. Auld
Keyword(s):  
Seed Bank ◽  
Significant Variation ◽  
Reproductive Strategies ◽  
Plant Age ◽  
Obligate Seeder ◽  
Seed Bank Dynamics ◽  
Banksia Ericifolia ◽  
Regeneration Strategies ◽  
In Fire ◽  
Number Of Seeds

The seed bank dynamics of the three co-occurring obligate-seeder (i.e. fire-sensitive) Proteaceae species, Banksia ericifolia, Banksia marginata and Petrophile pulchella, were examined at sites of varying time since the most recent fire (i.e. plant age) in the Sydney region. Significant variation among species was found in the number of cones produced, the position of the cones within the canopy, the percentage of barren cones produced (Banksia species only), the number of follicles/bracts produced per cone, and the number of seeds lost/released due to spontaneous fruit rupture. Thus, three different regeneration strategies were observed, highlighting the variation in reproductive strategies of co-occurring Proteaceae species. Ultimately, B. marginata potentially accumulated a seed bank of ~3000 seeds per plant after 20 years, with ~1500 seeds per plant for P. pulchella and ~500 for B. ericifolia. Based on these data, B. marginata and B. ericifolia require a minimum fire-free period of 8–10 years, with 7–8 years for P. pulchella, to allow for an adequate seed bank to accumulate and thus ensure local persistence of these species in fire-prone habitats.

Plasma Levels of Protein S, Protein C, and Factor X: Effects of Sex, Hormonal State and Age

1995 ◽  
Vol 74 (05) ◽  
pp. 1271-1275 ◽  
Author(s):  
C M A Henkens ◽  
V J J Bom ◽  
W van der Schaaf ◽  
P M Pelsma ◽  
C Th Smit Sibinga ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Postmenopausal Women ◽  
Protein C ◽  
Blood Donors ◽  
Premenopausal Women ◽  
Protein S ◽  
The Other ◽  
Factor X ◽  
Normal Ranges

SummaryWe measured total and free protein S (PS), protein C (PC) and factor X (FX) in 393 healthy blood donors to assess differences in relation to sex, hormonal state and age. All measured proteins were lower in women as compared to men, as were levels in premenopausal women as compared to postmenopausal women. Multiple regression analysis showed that both age and subgroup (men, pre- and postmenopausal women) were of significance for the levels of total and free PS and PC, the subgroup effect being caused by the differences between the premenopausal women and the other groups. This indicates a role of sex-hormones, most likely estrogens, in the regulation of levels of pro- and anticoagulant factors under physiologic conditions. These differences should be taken into account in daily clinical practice and may necessitate different normal ranges for men, pre- and postmenopausal women.

On the role of the dispute between "non-possessors" and "Josephites" in the culture of Moscow's prediction

1998 ◽  
pp. 61-62
Author(s):  
N. S. Jurtueva
Keyword(s):  
The Other ◽  
Moral Transformation ◽  
15Th Century ◽  
The Future ◽  
Secular Power

In the XIV century. centripetal tendencies began to appear in the Moscow principality. Inside the Russian church, several areas were distinguished. Part of the clergy supported the specificobar form. The other understood the need for transformations in society. As a result, this led to a split in the Russian church in the 15th century for "non-possessors" and "Josephites". The former linked the fate of the future with the ideology of hesychasm and its moral transformation, while the latter sought support in alliance with a strong secular power.

From Container to Claustrum: Projective Identification in Couples

2014 ◽  
Vol 4 (2) ◽  
Author(s):  
Tamara Feldman
Keyword(s):  
Psychological Health ◽  
Projective Identification ◽  
The Self ◽  
The Other ◽  
Intimate Partners ◽  
And Control ◽  
The Relationship ◽  
As If

This paper is a contribution to the growing literature on the role of projective identification in understanding couples' dynamics. Projective identification as a defence is well suited to couples, as intimate partners provide an ideal location to deposit unwanted parts of the self. This paper illustrates how projective identification functions differently depending on the psychological health of the couple. It elucidates how healthier couples use projective identification more as a form of communication, whereas disturbed couples are inclined to employ it to invade and control the other, as captured by Meltzer's concept of "intrusive identification". These different uses of projective identification affect couples' capacities to provide what Bion called "containment". In disturbed couples, partners serve as what Meltzer termed "claustrums" whereby projections are not contained, but imprisoned or entombed in the other. Applying the concept of claustrum helps illuminate common feelings these couples express, such as feeling suffocated, stifled, trapped, held hostage, or feeling as if the relationship is killing them. Finally, this paper presents treatment challenges in working with more disturbed couples.

Thomas More's “rule” of pleasure before, after, and inUtopia

Moreana ◽  
2017 ◽  
Vol 54 (Number 207) (1) ◽  
pp. 36-56
Author(s):  
Gerard Wegemer
Keyword(s):  
Human Nature ◽  
The Other ◽  
Biblical Allusions ◽  
De Officiis

After establishing a context of More's lifelong engagement with the “calculus” of pleasure, this essay shows how the section devoted to the Utopians' pleasure philosophy is structured around five formulations of a “rule” to calculate “true and honest [honesta]” pleasure in ways that playfully imitate and echo the “rule” Cicero formulates several times in De officiis to discern one's duty when there seems to be a conflict between honestas et utilitas. When followed, the Utopian pleasure calculus shows the necessary role of societas, officii, iustitia, caritas, and the other aspects of human nature, most importantly friendship, that Cicero stresses in his rule and that he argued Epicurus ignored. Much of the irony and humor of this section depends on seeing the predominance of Ciceronian vocabulary in Raphael's unusual defense [patrocinium] of pleasure, rather than a Ciceronian defense of duty rooted in honestas. Throughout, however, this essay also shows how More goes beyond Cicero by including Augustinian and biblical allusions to suggest ways that our final end is not as Epicurus or the Stoics or Cicero claim; the language and allusions of this section point to a level of good cheer and care for neighbors and for God in ways quite different from any classical thinker.

BLOCKADE OF THE SURGE OF PROLACTIN AT PRO-OESTRUS BY ADMINISTRATION OF ANTI-OESTROGENIC SUBSTANCE, MER-25

1973 ◽  
Vol 74 (4) ◽  
pp. 769-774 ◽  
Author(s):  
Akira Yokoyama ◽  
Hiroshi Tomogane ◽  
Katuaki Ôta
Keyword(s):  
Strong Evidence ◽  
The Other ◽  
Other Hand

ABSTRACT A non-steroidal oestrogen antagonist, MER-25, was administered to cycling rats for elucidating the role of oestrogen in the surge of prolactin observed on the afternoon of pro-oestrus (POe). In animals injected with 20 mg of MER-25 intramuscularly on the afternoon (16.30 h) of the first day of dioestrus (D-1), the surge of prolactin was blocked while the level of prolactin on the afternoon of POe of these animals was significantly higher than that of the corresponding controls injected with oil. Ovulation was also blocked in these animals treated with the drug on the afternoon of D-l. On the other hand, treatment on the morning (10.30 h) of the 2nd day of dioestrus failed to prevent not only the surge of prolactin but also ovulation. These observations provide strong evidence for the view that oestrogen is responsible for the surge of prolactin on the afternoon of POe, and that the surge is accompanied by that of LH.

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