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1

Seed Bank and Vegetation in a Closed Depression in Agricultural Landscape : Relation to Moisture Conditions and Soil Properties

Franczak Magdalena, Franczak Łukasz

Polish Journal of Ecology

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2020

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Vol. 68, nr 3

195--210

EN

The aim of the study was to estimate the effect of habitat factors such as moisture conditions and some physicochemical soil characteristics on the structure of the vegetation and the soil seed bank, and to compare species composition of the vegetation cover and the seed bank along the soil moisture and fertility gradients in closed depression in agricultural landscape. Based on the averaged results of the extent and time of stagnation of the water, along the transect four habitat moisture zones were distinguished (dry, periodically moist, moist, and wet). In eighteen study plots we analysed flora, soil seed bank, and contents of Ca, Mg, K, Mn, Fe and pH of the soil. The analysed closed depression is characterised by high variability in moisture conditions and in the physical and chemical properties of the soil. The most important factors affecting the diversity of the vegetation cover and seed bank were the duration of water stagnation and the content of Fe and Mn in the soil. The lowest plant species richness and the smallest seed resources were determined for the wet zone of the depression. An increase in the habitat moisture level was accompanied by a decline in the floristic similarity between the vegetation cover and the seed bank.

2

Role of Seed Bank in Establishment of Single and Mixed-Sowing Artificial Grasslands of Tibetan Plateau

Ma Z., Zhang C., Zhou H.-K., Yao B.-Q., Zhao X.-Q.

Polish Journal of Ecology

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2017

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Vol. 65, nr 4

334--344

EN

Artificial grassland establishment is one of the fastest and most effective ways to restore the productivity of degraded grasslands. Little is known about the effect of different types of artificial grassland establishment (i.e., single- and mixed-sowing grassland establishment with perennial grasses) on soil seed bank in degraded grassland ecosystems. Single-sowing population of a high yield species usually has a great standing biomass causing shading that may inhibit germination of seeds in soil seed bank. Thus, we hypothesized that there is higher species richness and seed density in the soil seed bank of single-sowing than mixed-sowing grasslands. Here, we investigated the soil seed bank in four-year old single-sowing and mixed-sowing and control (degraded) grasslands on the Qinghai-Tibetan Plateau. We found that the autumn seed bank of mixed-sowing grasslands had lower species richness and seed density than single-sowing grasslands, while the summer soil seed bank (persistent seed bank) showed little differences. There were differences in biomass among the three grasslands (single-sowing > mixed-sowing > control), but there was no differences in species richness of vegetation. In sum, our results of the autumn seed bank support our hypothesis. Greater above-ground biomass in single-sowing grasslands could generally cause low light availability preventing seeds in soil from germinating and support more seed output, which both may indirectly or directly result in the relatively higher species richness and seed density in the soil seed bank. Our results also suggest that artificial grasslands usually returning to native grasslands in terms of production and species composition after several years is likely due to stability of the persistent soil seed bank.

3

New Stand of Invasive Neophyte Ambrosia artemisiifolia L. and Its Potential Reproduction

Csontos P., Angyal Z., Chmura D., Nagy J., Halbritter A., Tamás J.

Polish Journal of Ecology

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2015

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Vol. 63, nr 3

453--459

EN

A new stand, formed by some fifty individuals of Ambrosia artemisiifolia L., an invasive plant of alien origin, was discovered at the Katowice railway station (southern Poland), in 2011. Two years later, the stand (increased to more than 160 individuals in the meantime) was re-visited, phytosociological survey was made, and four soil cores (5 cm deep and 80 cm2 surface area, each) were taken for seed bank studies. The phytosociological sampling revealed 28 co-occurring vascular species, most of them representing hemicryptophyte and geophyte life forms. According to Ellenberg's values, the species pool indicated sunny (L7 and L8 species dominating) and semi-dry (mainly F4 species) habitat for the common ragweed population, whereas Zarzycki's soil granulometric data reflected coarse-grained soil. Albedo of the soil was lower than that of the vegetation thus sparsely vegetated sites were considered as heat accumulating microhabitats that might support establishment of the thermophilic A. artemisiifolia. During soil seed bank analysis a high number of naturally opened fruits (dehiscent achenes) were found (718.75 per m2) most probably indicating frequent germination in previous years. Greenhouse germination tests proved successful germination of 125 individuals per m2, which was considered enough to maintain the A. artemisiifolia stand at the station. The results call attention to a newly discovered, established population with increasing demography of A. artemisiifolia, a highly allergenic introduced weed of Poland.

4

Post-fire changes of soil seed banks in the Elary succesionsl stage of pine forest

Kwiatkowska-Falińska A., Jankowska-Blaszczyk M., Jaroszewicz B.

Polish Journal of Ecology

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2014

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Vol. 62, nr 3

455--466

EN

Our research was conducted on abandoned fields which had been undergoing spontaneous succession for 40–50 years and then were partly burnt. The main objective of the study was to examine if spontaneous fire in the early successional stage of pine forest causes a decrease in the number of species, diversity and density of seed banks, and an increase in the share of species forming long term persistent seed banks. Standing vegetation and soil seed banks were studied on 20 permanent plots on adjacent burnt and unburnt sites one and twelve years after spontaneous fire. One year after the fire the number of species in the seed banks of both areas was similar (11 and 12 species). In the burnt area the Shannon index and the floristical similarity between the seed bank and standing vegetation were lower, and seed density five times higher than in the unburnt area (15 691.5 m-2 vs.3426.5 m-2). This was mainly the effect of the high number of seedlings of Calluna vulgaris (L.) Hull and Spergula morisonii Boreau germinating from the burnt plots. Twelve years after the fire the number of species in both seed banks had increased little, but seed density in the burnt area (1742.5 m-2) had decreased 16 times, while that of the unburnt area had changed only slightly (2875.5 m-2). At the same time the Shannon index for the burnt area increased considerably, whereas for the unburnt one it did not change. Our study shows that the long-term persistent soil seed bank plays a fundamental role at the beginning of the post-fire regeneration of temperate coniferous forest vegetation. Germination of Calluna seedlings from the burnt soil seed banks in several times higher numbers than from unburnt soil seed banks may suggest that heat from the fire promotes a loss of dormancy in the heather seeds.

5

Spatial heterogeneity of soil seed banks in sandy grasslands under fencing and grazing in Horqin sandland, Northern China

Zuo X., Zhao X., Zhao H., Zhang T., Wang S., Knops J., Kochsiek A.

Polish Journal of Ecology

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2013

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Vol. 61, nr 2

221--231

EN

Understanding composition, structure and spatial heterogeneity in soil seed banks is important for the management of grassland ecosystem. Although the effect of fencing and grazing on vegetation composition is widely known, information on species composition, seed density and spatial heterogeneity of soil seed banks in sandy grasslands under fencing and grazing is still lacking. We measured the species composition and seed density of soil seed banks in fenced grassland, grazed grassland and grazed shrubby grassland in Horqin Sand Land, Northern China. By applying the geostatistical methods, we assessed how fencing and grazing affected spatial heterogeneity of soil seed banks in sandy grasslands. Total seed density and species richness in soil seed banks were lower in fenced grassland than in either grazed grassland or grazed shrubby grassland. Seed density and species richness of annual species in soil seed banks were also lower in fenced grassland than in either grazed grassland or grazed shrubby grassland, while those of perennial species showed a reverse trend. The analysis of spatial autocorrelation ranges, fractal dimensions and distribution pattern maps from geostatistical methods showed that spatial heterogeneity of seed density and species richness in soil seed banks were also lower in fenced grassland than in either grazed grassland or grazed shrubby grassland. Continuous fencing increases the seed density and species richness of perennial species in soil seed banks, as well as results in a decrease in spatial heterogeneity of seed density and species richness in soil seed banks. So, continuous fencing should be considered to restore the degraded sandy grasslands in management of semiarid grassland ecosystems.

6

Miedze Wołynia Zachodniego jako siedliska rzadkich nawapiennych gatunków roślin

Czarnecka J.

Woda-Środowisko-Obszary Wiejskie

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2011

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T. 11, z. 2

43-52

PL

Celem niniejszej pracy było udzielenie odpowiedzi na pytanie, czy miedze w krajobrazie rolniczym Wołynia Zachodniego oraz przylegające do nich marginesy pól mogą stanowić istotne refugia gatunków murawowych oraz nawapiennych chwastów o przyśródziemnomorskim typie zasięgu. Przeanalizowane zostały dane o pokrywie roślinnej 4 równoległych miedz o różnej szerokości, wieku i poziomie stabilizacji (ich łączna długość wynosi ok. 1000 m) oraz zasoby banku nasion w glebie pobranej wzdłuż najstarszej z miedz. Wzdłuż miedz stwierdzono obecność 67 gatunków roślin, w tym 9 murawowych oraz 16 nawapiennych chwastów. Na różnorodność biologiczną pokrywy roślinnej miedzy w największym stopniu wpływa wiek miedzy, z czym wiąże się jej szerokość i stopień stabilizacji. Gatunki murawowe koncentrują się w tych częściach miedz, które przylegają do murawy kserotermicznej, natomiast chwasty nawapienne są rozmieszczone równomiernie, na całej długości liniowych struktur. W glebowym banku dominują diaspory jednorocznych chwastów, a gatunki murawowe mają stosunkowo niewielki udział.

EN

The aim of the study was to check if marginal habitats (baulks and adjacent field margins) in agriculture landscape of Western Wolhynia can play a role of important refuges for grassland species and calciphilous weeds of the submediterranean range. Vegetation data were collected along four parallel baulks (total length was c.a. 1000 m; age, width and the level of stabilisation of each baulk were different); soil seed bank of one of the baulks was also analysed. Sixty seven species were found along the baulks, including 9 xerothermic grassland species and 16 calciphilous weeds. The main factor responsible for vegetation biodiversity was the baulk age, and consequently width and level of stabilisation. Grassland species were concentrated in the stretches of baulks closest to the grassland patch in contrast with calciphilous weeds distributed evenly along the baulks. Soil seed bank was dominated by annual weeds, the share of grassland species was much lower.

7

Soil seed banks in lakeshore wetlands : relation to the extant vegetation

Peng Y., Wu N., Gao X., Fang Z., Xiao W.

Polish Journal of Ecology

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2010

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Vol. 58, nr 3

449-457

EN

Seed bank composition and germination characteristics are necessary for modeling wetland vegetation composition. Yet there are few studies about the seed bank difference between plant communities in lakeshore wetlands. Seed banks are also known to play important roles in the vegetation restoration process. Environmental factors such as water level, temperature, or nutrient levels can affect vegetation composition and seed bank composition. The relationships between environmental factors and seed banks of wetlands in the field are still unknown. The Jiuzhaigou Nature Reserve is located at the eastern edge of Qinghai-Xizang Plateau. The lakeshore wetland vegetation is dominated by Phragmites australis (Cav.)Trin. ex Steud., Typha latifolia L., Carex pamirensis C. B. Clarke, Equisetum fluviatile L. The wetlands in Jiuzhaigou (118 lakes) are under strong pressure such as trampling and enhanced construction for travel. Plant restoration is necessary for protection of these areas. We investigated the soil seed bank in six lakeshore wetlands in this area using the seedling emergence method. Sediment samples (0-2 cm, 2-5 cm, 5-10 cm intervals from surface to bottom) were taken with core (diameter 5 cm) in April and from each replicate samples were spread on two plastic trays. Trays were randomly arranged in the greenhouse and watered daily. Seedlings were counted weekly after emergence, and removed as soon as they could be identified. Our study showed that seed density in all soil layers samples was negatively correlated to water depth. Water depth can explain 45% variance of species richness in surface layer in sediment. Species richness in extant vegetation can explain 45, 48, 25% variance of species richness in total 10 cm and in 2-5 cm and 5-10 cm layer sediment respectively. Dominant species cover in extant vegetation, site altitude, total nitrogen, total phosphorus and total organic carbon in soil showed no correlation with species richness in seed bank. Mean seed densities in wetlands ranged from 0 to 15945 m[^-2]. A total of 23 species germinated in seed bank, while 85 species were found in extant vegetation. The dominant species in seed bank and extant vegetation showed great difference. The total number of species and seedlings that germinated in different layers was not significantly different. But the second layer had the greatest seed density. The relationship between seed bank and extant vegetation differed from one species to another. We should use different restoration strategies for different plant communities.

8

Reproductive potential of the alien species Asclepias syriaca (Asclepiadaceae) in the rural landscape

Csontos P., Bozsing E., Cseresnyes I., Penksza K.

Polish Journal of Ecology

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2009

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Vol. 57, nr 2

383-388

EN

In the beginning of its introduction Common milkweed, Asclepias syriaca L. was used in Hungary as ornamental plant. After escaping from cultivation it has become wide spread during last decades of the 20th century. Nowadays, it covers large areas especially on sandy soils, and its further appearance is expected on dry, deforested and degraded areas. Two neglected fields and one abandoned vineyard were selected. For sampling two quadrates of size 4 m[^2] were used at each stand. The stands were characterized by the following variables: density of stems, percentage of reproductive stems, average number of inflorescences, average number of fruits, fruits per all inflorescences on a stem, pods per fruited inflorescences on a stem, average number of seeds per fruit. In the same quadrates the soil seed bank was studied at two depths (0-5 cm and 5-10 cm). The results showed that the density of stand, percentage of reproductive specimens and average number of fruits were significantly higher on the neglected fields than on the abandoned vineyard. In the neglected fields large number of seeds were detected in the upper soil-layer (2.7-18.6 x 10[^3] seeds m[^-2]), but in the lower soil-layer much fewer seeds were found and only in one of the fields. Common milkweed seeds were almost completely missing from both soil layers of the abandoned vineyard. However, the seeds recovered from the soils practically did not germinated, indicating that seeds of earlier years sets have lost viability, i.e. the studied stands of A. syriaca did not form a persistent soil seed bank. Nevertheless, the fresh seed production of the neglected field populations, that can reach 7-10 thousands seeds m[^-2], may cause a very strong propagulum load not only in the site but also on the surrounding areas.

9

Rola glebowego banku nasion w renaturyzacji torfowisk na przykładzie Bagna Całowanie

Klimkowska A.

Woda-Środowisko-Obszary Wiejskie

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2006

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T. 6, z. 1

183-194

PL

W wyniku fragmentacji i zanikania ekosystemów mokradłowych, spowodowanego nieodpowiednim użytkowaniem, powierzchnia torfowisk w Europie Zachodniej zmniejszyła się w XX wieku o ponad 90%, a w Europie Centralnej i Wschodniej - szacunkowo o 50--90%. Zmeliorowane torfowiska określa się jako obszary zdegradowane przyrodniczo z powodu silnego odwodnienia, dużych wahań poziomu wód gruntowych oraz znacznego stopnia mineralizacji torfu. W celu przywrócenia i ochrony różnorodności biologicznej torfowisk, w wielu krajach są prowadzone projekty ochrony czynnej (nature management) oraz renaturyzacji (restoration) takich ekosystemów. W Polsce eksperymentalne prace renaturyzacyjne metodą usuwania zmurszałej wierzchnicy torfowiska na głębokość 20 i 40 cm są prowadzone na terenie Bagna Całowanie. Celem badań było sprawdzenie, czy w glebie znajdują się zdolne do kiełkowania nasiona roślin torfowiskowych (lub roślin łąk podmokłych), które umożliwiłyby spontaniczne odtworzenie się tej roślinności. Przeprowadzono analizy banku nasion metodą wschodu siewek. Na powierzchni, z której usunięto mursz, znaleziono niewiele zdolnych do kiełkowania nasion. Glebowy bank nasion był zdominowany przez kilka gatunków roślin ruderalnych (60% banku nasion) lub gatunków o szerokiej amplitudzie ekologicznej. Stwierdzono, że na badanym terenie istniejący glebowy bank nasion nie umożliwia spontanicznej regeneracji roślinności torfowiskowej.

EN

Due to fragmentation and disappearance of wetland ecosystems after their transformation into productive agricultural land, the surface of peatlands in Western Europe in the 20th century declined by over 90% and in Central and Eastern Europe by 50 to 90%. Severely drained peatlands suffer form desiccation, large fluctuations of groundwater levels and advanced peat mineralization. Still, some of those areas preserved natural values and fen ecosystems or semi-natural fen meadows of high biodiversity could be restored there. In many western countries, nature management or nature restoration actions are carried out in order to conserve and improve the biodiversity of peatland areas. In Poland such actions are applied in Całowanie Fen, where the top soil removal method is tested (removal of 20 and 40 cm of top soil). This technique allows local improvement of moisture conditions, nutrient impoverishment and removal of the ruderal and nitrophilous vegetation together with its seed bank. The objective of this study was to check if any viable seeds of the typical plant species of fens or fen meadows are still present in the soil seed bank. If present, the soil seed bank would contribute to the re-establishment of target vegetation on the restoration plots. Lack of persistent seed bank and limited natural dispersal of the target plant species have been identified as main limitations of meadow restoration in Western Europe. The soil seed bank analyses were done with the seed germination method. In the process of degradation, the target species seed bank has been depleted. In order to assess the extent of this depletion, the soil seed bank of the degraded fen (Całowanie Fen) and well-preserved fen (fen near village Lipsk) were compared. On restored plots after top soil removal few viable seeds have been found and the soil seed bank was dominated by a few ruderal (60%) or common species that tolerate wide range of environmental conditions (e.g. Juncus articulatus). We concluded that in the studied site, the restoration of fen meadow community can not rely on spontaneous recovery of vegetation from the soil seed bank.

10

Resumption of Growth of Weed Seeds from Soil in Laboratory Conditions.

Sławiński J., Połcik B.

Chemia i Inżynieria Ekologiczna

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1999

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Vol. 6, nr 7

665-672

EN

In pot experiments (1996 - 1998) the ability of weed seeds to resume growth in soil samples were studied. In general 4674 weeds/m2 emerged: 28% in 0-10 cm , 44% in 10-20 cm and 28% in 20-30 cm soil layer. Among the seedlings were summer annuals and summer or winter annuals. During the experiments 13 simulated tillages (rotary cultivator, plow) and 2 fallowings were made. After 148 days of experiments (3 tillages) emerged 51% total amonut of weeds, the next 349 days (fallowing - 171 +4 tillages - 178 days) resulted in 34% seedlings and during the last 412 days (fallowing 166 + 6 tillages - 246 days) were received 15% resumption of growth of seeds. In 776 days all viable seeds of Echcg emerged and after 909 days other 20 plants of Galpa/m2 and 22plants of Thlar/m2 (0,6% and 0,5% of the total amount of weeds resumed growth). Species: Echcg, Thlar and Galpa showed periodicity of resumption of growth of seeds.

PL

W doświadczeniach laboratoryjnych (1996-1998) badano wschody chwastów z nasion znajdujących się w próbkach glebowych. Ogółem wzeszło 4674 sztuk chwastów /m2, w tym 28% w 0-10 cm, 44% w 10-20 cm i 28% w 20-30 cm warstwie gleb. W czasie badań wykonano 13 symulacji uprawowych (bronowanie, orka) i 2 ugorowania. Łącznie z trzech warstw (0-30 cm) po 148 dniach badań (3 uprawy) wzeszło 51% chwastów, po dalszych 349 dniach 34% a po ostatnich 412 dniach wschody zwiększyły się o 15%. Po 776 dniach wyeliminowano z glebowego banku całkowity zapas żywotnych nasion Echcg (48 sztuk/m2), natomiast po 909 dniach badań zanotowano jeszcze wschody Galpa i Thlar w liczbie odpowiednio: 29 i 22 szt/m2. Gatunki: Echinochloa crus-galli, Thlaspi arvense i Galinsoga parviflora wykazały periodyczność wznawiania wzrostu z nasion.