Community Dynamics and Soil Seed Bank Ecology of Lane Mountain Milkvetch (Astragalus jaegerianus Munz)

2012 ◽  
Author(s):  
T. R. Huggins ◽  
B. A. Prigge ◽  
M. R. Sharifi ◽  
P. W. Rundel
1997 ◽  
Vol 13 (5) ◽  
pp. 659-680 ◽  
Author(s):  
J. W. Dalling ◽  
M. D. Swaine ◽  
Nancy C. Garwood

ABSTRACTSeasonal changes in the densities of dormant seeds in the soil around eight pioneer trees in the 50-ha Forest Dynamics Plot, on Barro Colorado Island, Panamá were studied, and how seed dispersal and seed dormancy influenced patterns of seed abundance and distribution were examined. Twenty-four, 3-cm-deep soil samples were collected on 30 m transects radiating out from each of the trees in each of four time-intervals through the year, and four 21-cm-deep samples were collected beneath the focal tree crowns. In the surface 0–3 cm of soil, germinable seed densities of all species combined declined from a peak of 1090 seeds m−2 in the mid-wet season in August, to 330 seeds m−2 by the end of the wet season in November. In contrast, at soil depths >3 cm, there was little variation in soil seed bank density through the year. Some variation in soil seed bank density for individual species could be accounted for by distance to reproductive conspecifics. Among species, abundance in the soil was negatively correlated with seed size. Seed persistence varied greatly among species at this site; after 1 y of burial in mesh bags, seed germinability of four species was near zero, while four other species showed no consistent decline in seed germinability after >2 y of burial. For at least one species, Trema micrantha, prolonged seed dormancy was also possible under natural conditions. Twenty-five percent of Trema seeds extracted from the soil at a site occupied by an isolated Trema tree that died between 1982 and 1985 were still germinable in 1994.


1998 ◽  
Vol 28 (10) ◽  
pp. 1471-1480 ◽  
Author(s):  
Geraldine L Tierney ◽  
Timothy J Fahey

The soil seed bank of the low-value, pioneer tree pin cherry (Prunus pensylvanica L.f.) appears to increase markedly after multiple, large-scale disturbance events, which may result in interference with the growth of high-value species. Seven northern hardwood forest sites of varying age and disturbance history in the White Mountains of New Hampshire were examined to quantify the patterns of accumulation and depletion of the pin cherry soil seed bank. The pin cherry seed bank accumulated in a predictable fashion based on pin cherry stem abundance. High- and low-density populations accumulated approximately 440 and 1900 viable seeds per pin cherry stem, respectively. Depletion of the seed bank appeared to be negligible in stands between age 40 and 60, and moderate (30% loss over 20 years) in stands between age 95 and 115. Short (e.g., 60-year) harvest rotation times may triple the size of the pin cherry soil seed bank, causing proliferation of this species with consequences for ecosystem and community dynamics, whereas longer rotation times of 120 years may allow enough depletion of the seed bank to stabilize population sizes.


2010 ◽  
Vol 26 (5) ◽  
pp. 714-719
Author(s):  
Ming LI ◽  
De-ming JIANG ◽  
Yong-ming LUO ◽  
Xiu-mei WANG ◽  
Bo LIU ◽  
...  

2021 ◽  
Vol 25 ◽  
pp. e01403
Author(s):  
Yao Huang ◽  
Hai Ren ◽  
Jun Wang ◽  
Nan Liu ◽  
Shuguang Jian ◽  
...  

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 500
Author(s):  
Zong Zhao ◽  
Yong Liu ◽  
Hongyan Jia ◽  
Wensheng Sun ◽  
Angang Ming ◽  
...  

Objective: To investigate the impact of different slope directions on the quantity and quality of the soil seed bank and seedling germination process of Castanopsis hystrix plantations. Method: Fixed sample plots in forest stands of Castanopsis hystrix were established on different slope directions (sunny slope, semi-sunny slope, semi-shady slope, and shady slope). The characteristics of the forest stand were investigated, and per-wood scaling was carried out. The temporal dynamics of the seed rain and seed bank were quantified using seed rain collectors and by collecting soil samples from different depths. The quantity and quality of the seeds were determined, and the vigor of mature seeds was measured throughout the study. Results: (1) The diffusion of Castanopsis hystrix seed rain started in mid-September, reached its peak from late October to early November, and ended in mid-December. (2) The dissemination process, occurrence time, and composition of the seed rain varied between the different slope directions. The seed rain intensity on the semi-sunny slope was the highest (572.75 ± 9.50 grains∙m−2), followed by the sunny slope (515.60 ± 10.28 grains∙m−2), the semi-shady slope (382.13 ± 12.11 grains∙m−2), and finally the shady slope (208.00 ± 11.35 grains∙m−2). The seed rain on the sunny slope diffused earliest and lasted the longest, while the seed rain on the shady slope diffused latest and lasted the shortest time. Seed vigor and the proportion of mature seeds within the seed rain were greatest on the semi-sunny slope, followed by the sunny slope, semi-shady slope, and the shady slope. (3) From the end of the seed rain to August of the following year, the amount of total reserves of the soil seed banks was highest on the semi-sunny slope, followed by the sunny slope then the semi-shady slope, and it was the lowest on the shady slope. The amount of mature, immature, gnawed seeds and seed vigor of the soil seed bank in various slope directions showed a decreasing trend with time. The seeds of the seed bank in all slope directions were mainly distributed in the litter layer, followed by the 0–2 cm humus layer, and only a few seeds were present in the 2–5 cm soil layer. (4) The seedling density of Castanopsis hystrix differed significantly on the different slope directions. The semi-sunny slope had the most seedlings, followed by the sunny slope, semi-shady slope, and the shady slope. Conclusions: The environmental conditions of the semi-sunny slope were found to be most suitable for the seed germination and seedling growth of Castanopsis hystrix, and more conducive to the regeneration and restoration of its population.


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