The Changes of Soil Seed Banks In Time Series Before And After The Invasive Artemisia Trifida Was Removed From Grassland

Abstract Artemisia trifida (giant ragweed) is an invasive weed with an expanding distribution area. In recent years it has been found to invade grasslands, bringing great challenges for effective weed control and restoration of native herbage. Although it has been reported that plant invasion can cause a decline in species richness and biodiversity in native seed banks, which may eventually lead to the depletion of native seed banks, few location- and species-specific case studies have been conducted regarding the dynamic characteristics of the invaded seed banks from invasion back to restoration. The purpose of this study was to compare and quantify the seed banks of grassland communities after (1) giant ragweed invasion for 0-8 years, and (2) giant ragweed removal, in Yili Valley, Xinjiang, China. The results showed that the duration of invasion determined whether giant ragweed could pose a significant threat to the native community seed bank. The seed bank density of native community had significantly decreased by 30.44% after 4 years of invasion, and in the sixth year, the species richness in the seed bank had decreased significantly by 12.36%. After the invasion had lasted for eight years, the seed bank density of the native community had decreased by 83.28%, the species richness in the seed bank decreased by 39.33%, and the seed bank tended to be homogeneous. After the giant ragweed was removed, the potential for restoration was limited by the residual seed bank. Three years after the restoration, although the density of seed banks increased significantly, new growth was dominated by weedy species, rather than crucial components of the grassland habitat. This study is of great significance to the control of giant ragweed and the restoration of grassland vegetation invaded by giant ragweed.

Download Full-text

Soil Seed Bank and Aboveground Vegetation in Grazing Lands of Southern Marmara, Turkey

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha3915844 ◽

2011 ◽

Vol 39 (1) ◽

pp. 96 ◽

Cited By ~ 6

Author(s):

Altıngül ÖZASLAN PARLAK ◽

Ahmet GÖKKUŞ ◽

Hasan Can DEMİRAY

Keyword(s):

Species Richness ◽

Seed Bank ◽

Soil Seed Bank ◽

Common Species ◽

Seed Banks ◽

Grazing Pressure ◽

Perennial Grasses ◽

Vegetation Survey ◽

Soil Seed Banks ◽

Grazing Lands

The composition and conservation of plant communities is greatly influenced by the soil seed bank. Information on the soil seed banks and the remaining vegetation in these ecosystems is crucial for guiding the restoration efforts. This study examines the size, species richness, diversity, uniformity, and similarity of soil seed banks and aboveground vegetation in 6 different grazing lands including coastal pasture, reseeded pasture, artificial pasture, lowland shrubland, ungrazed pasture, and hillside shrubland. Forty-eight soil samples were taken by cores with a diameter and depth of 10 cm from each of grazing lands in August of 2007. A vegetation survey was conducted using a 0.5 x 0.5-m quadrant in both the spring and fall. Eighty species were observed in soil seed banks and aboveground vegetation. The largest seed bank was observed in reseeded pasture (7,715 seed/m2), while the smallest seed bank was found in coastal pasture (2,755 seed/m2). Coastal pasture also possessed the least amount of aboveground vegetation (131 plants/m2). The most aboveground vegetation was found in ungrazed pasture (155 plants/m2). The most common species in seed banks were annual and perennial grasses in reseeded pasture, annual forbs in artificial pasture and hillside shrubland, and perennial forbs in low shrubland and ungrazed pasture. Species richness, diversity, and uniformity in seed banks were highest in lowland shrubland and lowest in artificial pasture. The seed bank and aboveground vegetation were similar in ungrazed pasture, coastal pasture, reseeded pasture, low shrubland, hillside shrubland and artificial pasture. Shrublands play an important role in species richness and the number of germinated seeds from seed banks of grazing lands in southern Marmara. The results showed that reseeding or a decrease in grazing pressure may improve the condition of grazing lands.

Download Full-text

Natural vegetation regeneration from soil seed banks in the cultivated edges of Sudd wetlands in Juba, Southern Sudan

East African Journal of Science, Technology and Innovation ◽

10.37425/eajsti.v2i2.214 ◽

2021 ◽

Vol 2 (2) ◽

Author(s):

Josephine Esaete ◽

Augustine Bongo ◽

Thomas Lado ◽

Tomor Bojoi ◽

Henry Busulwa

Keyword(s):

Species Richness ◽

Species Composition ◽

Seed Bank ◽

Natural Regeneration ◽

Soil Seed Bank ◽

Seed Banks ◽

Interquartile Range ◽

Seed Density ◽

Soil Seed Banks ◽

Species Richness And Diversity

Soil seed banks are important for regeneration of degraded wetlands ecosystems. The Sudd wetlands of Juba city have long been encroached for crop cultivation. Seedling germination was monitored in a greenhouse to establish possible natural regeneration in Mindiari, Rejaf and Roton wetlands in the Sudd. Sixty-four species germinated from the soil seed bank of which 12.5% were dominated by Cyperus difformis and Typha capensis. The findings showed that median wetland species richness in Mindiari was 1.5 (interquartile range = 0.75?3.5), Rejaf 2.5 (interquartile range = 1.0 ? 4.0), Roton 3 (interquartile range = 1.0 ? 5.0) while median Shannon-Wiener diversity was 1.5 (1.14 ?1.73), 1.43 (1.01?1.66), 1.15 (0.98?1.67) for Mindiari, Rejaf and Roton respectively. Both the median seed species richness and diversity were not significantly different among the study wetlands. The median of seed density (56.1) was significantly higher in Roton than in Mindiari (36.7) and Rejaf (29.4) wetlands. The NMDS results showed that species composition of Mindiari and Rejaf was different from Roton. It is concluded that growing crops in wetlands did not influence species richness and diversity but it reduced seed density and altered species composition. Although wetland species were not significantly different in the three-wetland categories, dominance of canopy species belonging to Typhaceae and Cyperaceae indicates that these species are resilient to cultivation and could facilitate natural regeneration of cultivated wetlands edges of the Sudd region in Juba. Further research should examine effect of cultivation duration and flooding regimes on soil seed bank species richness, diversity, and density and composition.

Download Full-text

Similarity between seed bank and herb layer in a natural deciduous temperate lowland forest

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.2010.021 ◽

2011 ◽

Vol 79 (2) ◽

pp. 157-166 ◽

Cited By ~ 3

Author(s):

Maciej Wódkiewicz ◽

Anna Justyna Kwiatkowska-Falińska

Keyword(s):

Seed Bank ◽

Soil Seed Bank ◽

Similarity Index ◽

Seed Banks ◽

Herb Layer ◽

Managed Forests ◽

Lowland Forest ◽

Soil Seed Banks ◽

Dominance Structure ◽

Species Similarity

Forest seed banks mostly studied in managed forests proved to be small, species poor and not reflecting aboveground species composition. Yet studies conducted in undisturbed communities indicate a different seed bank characteristic. Therefore we aimed at describing soil seed bank in an undisturbed forest in a remnant of European lowland temperate forests, the Białowieża Forest. We compared similarity between the herb layer and seed bank, similarity of seed bank between different patches, and dominance structure of species in the herb layer and in the seed bank of two related oak-hornbeam communities. We report relatively high values of Sorensen species similarity index between herb layer and seed bank of both patches. This suggests higher species similarity of the herb layer and soil seed bank in natural, unmanaged forests represented by both plots than in fragmented communities influenced by man. Although there was a set of core seed bank species present at both plots, yielding high Sorensen species similarity index values, considerable differences between plots in seed bank size and dominance structure of species were found, indicating spatial variability of studied seed bank generated by edaphic conditions. Dominance structure of species in the herb layer was not reflected in the underlying seed bank. This stresses, that natural forest regeneration cannot rely only on the seed bank, although some forest species are capable of forming soil seed banks. While forest seed banks may not reflect vegetation composition of past successional stages, they may inform on history and land use of a specific plot.

Download Full-text

Rainfall in growing season determines the size of an annual-dominated soil seed bank in a desert ecosystem

10.22541/au.160770873.35234932/v1 ◽

2020 ◽

Author(s):

Ya-Fei Shi ◽

Zengru Wang ◽

Bing-Xin Xu ◽

Jian-Qiang Huo ◽

Rui Hu ◽

...

Keyword(s):

Environmental Factors ◽

Species Composition ◽

Seed Bank ◽

Soil Seed Bank ◽

Growing Season ◽

Seed Banks ◽

Desert Ecosystem ◽

Perennial Herb ◽

Desert Ecosystems ◽

Soil Seed Banks

Soil seed banks may offer great potential for restoring and maintaining desert ecosystems that have been degraded by climate change and anthropogenic disturbance. However, few studies have explored the annual dynamics in the composition and relative abundance of these soil seed banks. We conducted a long-term observational study to assess the effects of environmental factors (meteorology and microtopography) and aboveground vegetation on the soil seed bank of the Tengger Desert, China. The desert seed bank was dominated by annual herbs. We found that more rainfall in the growing season increased the number of seeds in the soil seed bank, and that quadrats at relatively higher elevations had fewer seeds. The species composition had more similarity in the seed bank than in the aboveground vegetation, though the seed bank and aboveground vegetation did change synchronously due to the rapid propagation of annuals. Together, our findings suggest that the combined effects of environmental factors and plant life forms determine the species composition and size of soil seed banks in deserts. Thus, if degraded desert ecosystems are left to regenerate naturally, the lack of shrub and perennial herb seeds could crucially limit their restoration. Human intervention and management may have to be applied to enhance the seed abundance of longer-lived lifeforms in degraded deserts.

Download Full-text

Characterization and ecological significance of a seed bank from the Upper Pennsylvanian Wise Formation, southwest Virginia

Acta Palaeobotanica ◽

10.1515/acpa-2017-0017 ◽

2017 ◽

Vol 57 (2) ◽

pp. 165-175 ◽

Cited By ~ 2

Author(s):

Petra S. Yehnjong ◽

Michael S. Zavada ◽

Chris Liu

Keyword(s):

Seed Size ◽

Seed Bank ◽

Seedling Establishment ◽

Environmental Variability ◽

Seed Banks ◽

Evolutionary Strategy ◽

Predator Population ◽

Seed Density ◽

Soil Seed Banks ◽

Large Seed

AbstractSoil seed banks are important to the maintenance and restoration of floras. Extant seed banks exhibit unique characteristics with regard to the distribution of seed size and seed density. Seeds were recovered from the Upper Pennsylvanian Wise Formation in southwest Virginia. Structurally preserved seeds were also examined from coal balls of the Pennsylvanian Pottsville and Allegheny Groups, Ohio. The size distribution of the seeds from the Wise Formation is similar to that of structurally preserved seeds of the Upper Pennsylvanian Pottsville and Allegheny Group coal balls. In contrast, the seed size distributions in extant wetland, grassland, woodland and forest habitats are significantly narrower than that of seeds from the Pennsylvanian seed banks. Larger seeds are less dependent on light for germination, and aid in seedling establishment more than smaller seeds, especially in dense stable forests where disturbance events are rare. Large seed size may contribute to increased seed longevity, which reduces the effect of environmental variability on seed germination and development. The significantly larger size of the Palaeozoic seeds may have imparted an advantage for seedling establishment in the dense Palaeozoic forests. The preponderance of large seeds may be a result of the absence of large seed predators (e.g. herbivorous tetrapods), and may have been an evolutionary strategy to minimize damage to the embryo from a predator population dominated by small invertebrates with chewing or sucking mouthparts. The estimated seed density of 192 seeds/m2in the Palaeozoic seed bank falls within the range of modern seed banks, but at the lower end of modern seed bank densities in a variety of habitats.

Download Full-text

Dynamics in the emergence of dormant and non-dormant herbaceous species from the soil seed bank from a Brazilian dry forest

Journal of Plant Ecology ◽

10.1093/jpe/rtaa008 ◽

2020 ◽

Vol 13 (3) ◽

pp. 256-265 ◽

Cited By ~ 1

Author(s):

José Djalma de Souza ◽

Bruno Ayron de Souza Aguiar ◽

Danielle Melo dos Santos ◽

Vanessa Kelly Rodrigues de Araujo ◽

Júlia Arruda Simões ◽

...

Keyword(s):

Seed Bank ◽

Linear Models ◽

Temporal Dynamics ◽

Soil Seed Bank ◽

Seed Banks ◽

Dry Forest ◽

Herbaceous Species ◽

Physical Dormancy ◽

Soil Seed Banks ◽

Interspecific Differences

Abstract Aims In dry tropical forests, herbaceous species may have dormancy mechanisms and form persistent and transient seed banks in the soil. Evolutionarily acquired, these mechanisms are efficient for the establishment and survival of these herbs, especially in forests with unpredictable climates, such as the Caatinga. Thus, our objective was to verify whether the studied herbaceous species adopt the physical dormancy mechanism and how these natural barriers are overcome, to understand the temporal dynamics existing in the soil seed bank from a Brazilian dry tropical forest. Methods Seeds of five native herbaceous species from the Caatinga forests were selected and submitted to pre-germinative treatments for verifying the presence of physical dormancy. We collected soil samples in the rainy and dry seasons for four consecutive years and monitored the emergence of the selected herbaceous in the greenhouse. We verified the differences in germination and seed bank emergence in the soil by generalized linear models. Important Findings The presence and absence of physical dormancy were observed in seeds from Caatinga herbaceous species. We found intraspecific and interspecific differences in the herbaceous emergence from soil seed banks between years and climatic seasons. In perennial herbs, consecutive lack of emergence between seasons and years was frequent, which suggests a direct relationship with the mechanism of physical dormancy and the environmental conditions necessary to overcome integument barriers. In these species, seed dimorphism and dormancy may confer additional advantages to their survival. Moreover, presenting intermediate levels of physical dormancy in an annual species may be an evolutionary adjustment to rainfall unpredictability. In contrast, we found that the annual herb without dormancy is more sensitive to seasonal and interannual climate changes, as evidenced by the increase and significant reduction of its emergence in the soil seed bank. These differences acquired evolutionarily are advantageous for the establishment of herbaceous populations, mainly in semiarid regions with an unpredictable climate.

Download Full-text

The role of seedbanks in invasions by Hyparrhenia hirta (L.) Stapf in Australia

The Rangeland Journal ◽

10.1071/rj19039 ◽

2019 ◽

Vol 41 (5) ◽

pp. 383 ◽

Cited By ~ 1

Author(s):

Vinod K. Chejara ◽

Paul Kristiansen ◽

R. D. B. (Wal) Whalley ◽

Brian M. Sindel ◽

Christopher Nadolny

Keyword(s):

South African ◽

Seed Production ◽

Seed Dormancy ◽

Seed Bank ◽

Soil Seed Bank ◽

Perennial Grass ◽

Seed Banks ◽

Invasive Weed ◽

South Wales ◽

Poor Seed

Hyparrhenia hirta (L.) Stapf (also known as Coolatai grass, South African bluestem or thatching grass) has become a serious invasive weed in Australia. Within its native range, it is generally regarded as a useful grass particularly for thatching, and seed production is low with a low soil seed bank of from 2 to 200seedsm–2. Several hundred accessions of H. hirta were deliberately introduced into Australia up until the 1980s and nearly all were discarded because of poor seed production. However, at least one introduction in the 1890s in northern New South Wales (NSW), Australia, has possibly contributed to the present serious weed problem. Annual seed production from roadside stands in northern NSW ranged from 7000 to 92000seedsm–2 in 2015. The soil seed bank under dense H. hirta infestations in the same region in 2006 and 2007, was found to be ~30000seedsm–2 mostly confined to the top 2cm, with few dormant seeds and a large reduction of these numbers over the next 12 months when further seed input was prevented. Similar studies of other perennial grass weeds have found seed banks of similar sizes, but dormancy mechanisms ensure that their seed banks last for at least 10 years without further seed input. These results suggest that the present weedy populations of H. hirta have dramatically increased fecundity enabling a large seed bank to develop beneath dense stands. The development of seed dormancy and consequently a long-lived seed bank would make this weed even more difficult to control. Until seed dormancy develops, control of H. hirta in northern NSW can be effective provided further input into the seed bank can be prevented.

Download Full-text

Soil Seed Banks of Adjacent Unlogged Rain-Forest Types in North-Queensland

Australian Journal of Botany ◽

10.1071/bt9900261 ◽

1990 ◽

Vol 38 (3) ◽

pp. 261 ◽

Cited By ~ 17

Author(s):

AW Graham ◽

MS Hopkins

Keyword(s):

Seed Bank ◽

Forest Type ◽

Soil Seed Bank ◽

Floristic Composition ◽

Seed Banks ◽

Scaling Analysis ◽

Forest Types ◽

Total Size ◽

Soil Seed Banks ◽

Secondary Species

The size and floristic composition of soil seed banks under four adjacent, unlogged and structurally different rainforest types were assessed by exposing 17 surface soil samples (to 40mm depth) to germination-house conditions. The mean size of the seed bank in the undisturbed forest types was 240 seeds m-2 (s.d. 139). Seeds of secondary species dominated the soil seed banks in all forest types, although weed seeds constituted only 0.6-4.0%. Some forest types had characteristic component secondary species in the buried seed bank. Agglomerative classification and multidimensional scaling analysis of quantitative sample data indicated that the parent structural-environmental forest type was the dominant influence in determining composition of the soil seed banks. Comparisons of the seed banks of the intact rainforest with those of nearby disturbed forests showed the former to be 35 to 50% smaller in total size, and lacking in some distinctive secondary species. It was concluded that disturbance, both within and adjacent to rainforest, may influence soil seed bank compositions, and hence future patterns of regeneration.

Download Full-text

Germination asynchrony is increased by dual seed bank presence in two desert perennial halophytes

Botany ◽

10.1139/cjb-2019-0071 ◽

2019 ◽

Vol 97 (11) ◽

pp. 639-649 ◽

Cited By ~ 1

Author(s):

Arvind Bhatt ◽

Narayana R. Bhat ◽

Flavio Lozano-Isla ◽

David Gallacher ◽

Andrea Santo ◽

...

Keyword(s):

Seed Bank ◽

Environmental Conditions ◽

Germination Rate ◽

Soil Surface ◽

Seed Banks ◽

Viable Seed ◽

Plant Recruitment ◽

Soil Seed Banks ◽

Desert Habitat

Maintaining a viable seed bank throughout the germination season is considered very important for plant recruitment in desert environments, where environmental conditions are unpredictable. Seeds from fully matured Seidlitzia rosmarinus Bunge ex Boiss and Halothamnus iraqensis Botsch. were collected in December 2016, then April, June, and September 2017 from both soil-surface and aerial seed banks. Both of the species were selected mainly by their capacity to rehabilitate saline coastal sites. Germination was analyzed under two photoperiods (0 or 12 h light per day), with winged or dewinged perianths. Seidlitzia rosmarinus had a shorter seasonal range in comparison with H. iraqensis (6 and 9 months, respectively), and the presence of a winged perianth reduced the germination rate of both species. A permanent winged perianth significantly inhibited the germination rate in both species. In the absence of perianth, the germination registered in December 2016 was mostly 100%, but declined to around 20% in September 2017. Seeds are thus more likely to germinate after scarification from wind mobilization, and do not require burial. Our results show that seeds of both the aerial and soil banks are transitory, and viable only during the winter months. Taken together, the combination of aerial and soil seed banks has greatly facilitated germination asynchrony in their environmentally unpredictable desert habitat.

Download Full-text