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Questions Evaluating seed production as a community function in species-rich temperate grasslands, we asked: (1) Do ancient and restored grasslands differ in the composition of seed-producing species? (2) Do seed-producing species of ancient and restored grasslands differ in their functional traits and habitat origin of their species? (3) How does seed production change during the season considering management; is seed production different for the whole community and for the subset of species occurring in both types of grasslands? Location White Carpathian Mts. (Czech Republic). Methods We assessed the species composition of flowering and fruiting species and collected propagule samples from three ancient and three restored grasslands. From the measured parameters, we estimated seed production for particular fruiting species. We combined these reproductive parameters with data on plant traits and plant status. Results Flowering species in restored grasslands produced three times higher seed numbers and three times lower seed mass than flowering species in ancient grasslands. At ancient sites, most seeds belonged to meadow specialist species; at restored sites, seeds of ruderal and generalist species prevailed. Prior to mowing, in both grassland types the seed producing species were characterised by a high capability of clonal reproduction, high leaf dry matter content, and wind pollination. After mowing, seed producing species were insect-pollinated species at ancient sites. This reflects dominance of grasses before mowing and forbs after mowing. Conclusions Higher seed number, lower seed mass and lower reliance on pollinators in restored grasslands indicate a different ecosystem functionality related to these parameters, in comparison with ancient grasslands. Specifically, seeds act as source for generative regeneration of resident species while resources for pollinators and seed herbivores are reduced. This maintains a differentiation of restored and ancient grasslands not only in terms of species composition but also in their effect on other trophic levels.

Effective restoration of meadows requires seeds of local provenance to preserve not only the species diversity but also the genetic identity of plant communities. We compared three different methods of seed harvesting from local meadow communities and assessed their efficiency in meadow restoration on ex-arable land. These methods were: brush harvesting once only, brush harvesting three times during a season, and green hay transfer. We observed the composition of species and functional traits of seed source meadows, sampled the three harvested seed mixtures and monitored plant communities restored on ex-arable land with this seed over the five following years. Green hay transfer was the method producing the highest amount of seeds (expressed as mass) and the highest number of species per unit of source-meadow area, followed by brush harvesting three times during one season and once only, respectively. This resulted in the highest establishment rate of species on ex-arable land in the green hay transfer method, followed by brush harvesting three times during one season and once only, respectively. Across all methods, species abundant in the seed mixture, having a low specific leaf area and a low capacity for lateral clonal spread, were the most successfully harvested and established ones. In the restored communities, mainly species number and cover of legumes but also of target meadow species increased with time, while ruderal weedy species decreased. Concerning species number and composition as well as trait spectrum, green hay transfer was the most successful method of restoration, resulting in a community most similar to the seed source meadow.

We present data of the grassland restoration experiment performed in the Bílé Karpaty Mts. (White Carpathians, Czech Republic) in dry species-rich meadows. First we harvested seed material in a preserved source meadow (donor site hereafter) by brush harvesting the vegetation once (B1 hereafter), brush harvesting three times during the season (B3 hereafter), and by cutting green hay (GH hereafter). Then we determined the species composition and seed quantity of the harvested material. Furthermore, we transferred the seeds to an experimental site on ex-arable land (receptor site hereafter), and monitored the development of the meadow communities in the following five years. Data are interpreted in: Á-J. Albert, O. Mudrák, I. Jongepierová, K. Fajmon, I. Frei, M. Ševčíková, J. Klimešová, J. Doležal, Grassland restoration on ex-arable land by transfer of brush-harvested propagules and green hay. Agriculture, Ecosystems & Environment 272 (2019), 74–82. Keywords: Bílé Karpaty, Functional traits, Grassland, Old field, Monitoring, Seed addition methods, Seed dispersal

Question Based on the spontaneous vegetation development of old-fields in the Nyirseg and Kiskunsag sand regions (Hungary), we aimed to answer the following questions using the chronosequence method: (1) how do the proportions of different functional groups change during succession; (2) which target species establish successfully in the old-fields during the course of succession; and (3) how successful is spontaneous succession in the recovery of target grasslands? Location Two sand regions of the Great Hungarian Plain: (1) the Nyirseg sand region (East Hungary, acidic sand, moderately continental climate) and the Kiskunsag (Central Hungary, calcareous sand, continental climate). Methods Altogether 24 old-fields were classified into young (

In the present paper we report original thousand-seed weight data for the flora of the Pannonian Basin. Our goal was to demonstrate the usefulness of seed weight databases by analysing seed weight data in relation to social behaviour types and life forms. We specifically asked the following questions: (i) how the seed weights are related to social behaviour type categories; (ii) how the life form of the species influences seed weight differences between respective social behaviour types? Own weight measurements are provided for 1,405 taxa; and for 187 taxa we published seed weight data for the first time: these were mostly endemics, orchids and/or species with Pontic, Caspian or continental distribution. Several taxonomic or functional groups are underrepresented in our database, like aquatic plants, rare arable weeds and sub-Mediterranean species. Problematic taxa, some difficult-to-harvest species or species with low seed production and cultivated adventives are also underrepresented. We found that the plant strategies expressed by social behaviour types were significantly different in terms of seed weights. The lowest seed weight scores were found for natural pioneers, whereas the highest ones were found for adventives and introduced cultivated plants. Short-lived herbaceous species had significantly higher seed weight scores than herbaceous perennials. No significant differences were found between specialists and generalists within the stress tolerant group. We found that short-lived graminoids possess heavier seeds than perennial graminoids, perennial and annual forbs. Naturalness scores were negatively correlated with seed weights. Our findings showed that seed collections and databases are not only for storing plant material and seed weight data, but can be effectively used for understanding ecological trends and testing plant trait-based hypotheses. Even the identified gaps underline the necessity of further seed collection and measurements.

Competition from native species is a key mechanism for biotic resistance to invasion. Accelerated germination to pre-empt resources or delayed germination and induced dormancy until the next growing season are two alternative strategies for annual invasive plants to avoid the drawbacks of competition at the seed stage. In Ambrosia artemisiifolia, both of these tactics could theoretically increase its long-term fitness. However,their relative importance has never been tested. We studied the germination pattern of A. artemisiifolia seeds in various competitive environments by experimentally modifying the life stage (seed, seedling,adult), density (low, high) and also the identity (intraspecific and 3 interspecific competitors) of neighbours in controlled conditions. When facing competition of seeds and seedlings at high densities or of particular identity, A. artemisiifolia accelerated its germination. In contrast, A. artemisiifolia followed a competition avoidance strategy in the presence of established adult heterospecific neighbours by delaying germination and reducing the germination fraction through induction of secondary dormancy. By testing the seedlings’ performance in the same competition situations as those of seeds, we showed that the germination responses were beneficial in the case of heterospecific, but not of conspecific neighbours. Keywords: common ragweed, competition, plant–plant interaction, environmental cueing, perception, density dependence