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1

Factors responsible for rapid diminishing of endangered grass plant Elymus farctus subsp. boreoatlanticus in phytocoenoses on dunes coast of Baltic Sea

100%
Wrobel M., Banas-Stankiewicz U.
Polish Journal of Ecology
|
2019
|
tom 67
|
nr 1
Sand couch-grass Elymus farctus (Viv.) Runemark ex Melderis subsp. boreoatlanticus (Simonet & Guin.) Melderis is a species of psammophytic perennial grass which grows on low embryo dunes, less frequently on white dunes, on a sandy substrate which is rich in chlorides, with a neutral or alkaline pH. The occurrence of E. farctus subsp. boreoatlanticus was confirmed on the Polish Baltic coast only in six stands out of 20 quoted in the 19th century and at the beginning of the 20th century, and the species is classified as critically endangered (CR). One of the largest populations of that species is situated on the Wolin Island (the Baltic Sea, west coast of Poland). The population of this species was monitored between 2015-2017 in the habitat of initial white coastal dunes (Nature 2000 site, code 2110), where the sand couch-grass is a characteristic species of Honckenyo-Agropyretum juncei R.Tx. 1955 plant association. The results of the conducted research show that the main reason for the rapid decline of the population of Elymus farctus subsp. boreoatlanticus on the western coast of Poland is recreational use of beaches, which is growing in an uncontrollable manner and puts pressure on this habitat, followed by complete destruction of psammophilous and halophilous vegetation. In addition, impact from marine abrasion inhibits the development of white coastal dunes where E. farctus subsp. boreoatlanticus occurs, and intensive aeolian sand accumulation hinder the regenerative ability of shoots and significantly limit vegetative reproduction.
2

The influence of disturbance type on precipitation − use efficiency at functional group and species scales in an arid habitat

84%
Busso C. A., Montenegro O. A., Torres Y. A., Giorgetti H. D., Rodriguez G. D.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 2
We used long-term datasets (1984–1992) to contrast precipitation-use efficiency estimates between various disturbance kinds at a functional group and/or a species scale. Effects of varying amounts of precipitation and plant cover on PUE were also examined. Field studies were conducted at northeastern, arid Patagonia, Argentina (40°39′49″S, 62°53′6.4″W). Within each management kind, biomass was sampled in 0.5 × 0.5m permanent plots (n = 30) over 9 years after defoliation at 5 cm stubble at the end of each growing season, and it was separated into species. Biomass sampling allowed determination of annual net primary production. Thereafter, species were grouped into each of three functional groups. Precipitation-use efficiency (PUE) was calculated as the total dry matter produced per unit surface area on any given year divided by the total rainfall in that year. Plant cover on 20 out of those 30 plots was determined to study the relationship between plant cover and PUE. The contribution of cool-season perennial grasses to total PUE was higher (P <0.05) than that found for the other two functional groups in all management kinds and years. PUE was similar (P> 0.05) in wet than dry years, and it was greater (P <0.05) or similar (P> 0.05), but not lower, on the more than less competitive perennial grass species in all management kinds. The relationship between plant cover and PUE was positive, linear (P <0.0000) and management-kind dependent.
3
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Biosystematic studies of Elymus repens [L.] Gould [Poaceae]: patterns of phenotypic variation

84%
Szczepaniak M.
Acta Societatis Botanicorum Poloniae
|
2009
|
tom 78
|
nr 1
51-61
Inter- and intrapopulational morphological variability of Elymus repens, a cool-season peren-nial grass and a tenacious weed that spreads both by seeds and rhizomes forming a thick and stout net, was examined. Multivariate statistical analysis of 48 initial morphological characters obtained from 44 population samples (1180 specimens) collected in different habitats revealed the conspicuous variation within E. repens. Principal Component Analysis revealed three extremes of the morphological gradient that were referred to as three varieties of E. repens: var. repens, var. aristatus and var. subulatus, not correlated with the habitat type or geographi-cal location. Canonical Discriminant Analysis proved the taxonomic usefulness of characters such as awned or awnless glumes and lemmas as well as the shape of glumes for variety di-stinction. Results of morphological analysis, in relation to the low level of genetic variation showed in the previous studies, suggest that the extensive morphological variation of E. re-pens can be caused by its plasticity where different morphological patterns are realized on the same genome basis. Additionally, the open-pollinated system of mating results in new combi-nations of morphological characters of plants that further reproduce vegetatively by rhizomes. The nomenclature, taxonomic descriptions and a key to the three varieties are provided.
4

Ecological adaptation strategies in alien species: effects of salinity, temperature and photoperiod on Spartina alterniflora Loisel. seed germination

84%
Yuan Z., Shi F.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 4
677-683
Spartina alterniflora (smooth cordgrass), a perennial grass native to the coastal marshes of eastern America, is widely distributed in northern China since 1979 of its introduction. In the tidal marshlands of north China, S. alterniflora has displaced native species and is presently dominant member of the community owing to its opportunistic characteristics. In this study we investigated S. alterniflora seed germination responses to different temperatures, between 5–25ºC in one thermoperiod (16/26ºC) and in two light treatments – 10/14h (night/day) photoperiod and dark conditions. Variations of seed germination at different storage temperatures and storage duration were also examined. In addition, the effect of different salt concentrations on seed germination was evaluated. The optimal temperature for germination was 25ºC and 16/26ºC (night/day) thermo-period – germination percentage was greater than 90%. Light intensity had no influence on the percent of seed germination and germination indices when seeds were exposed to identical temperatures. At 120 d of storage and -5, 0, and 5ºC temperatures, germination percentage exceeded 75%. The optimal salinity level for seed germination was 150 mM NaCl. Germination percentages were highest (> 90%) when salinity did not exceed 450 mM NaCl. The ability of S. alterniflora seeds to germinate under a wide range of temperature and light conditions resulted in continued seedling development under high salinity.
5

Effects of nutrient availability and competition between two grass species Leymus chinensis [Trin.] Tzvel. and Phragmites communis Trin. on the plant performance

67%
Ba L., Xiao N., Xu W., Wang D.
Polish Journal of Ecology
|
2008
|
tom 56
|
nr 3
453-462
Leymus chinensis (Trin.) Tzvel., a perennial grass, is a dominant species from arid to semi-arid steppes in northern China and eastern Mongolia. Phragmites communis Trin. is also a perennial grass, and is distributed widely in the world. In the natural grasslands of northeastern China, both species always co-exist as co-dominating species due to their common characteristics such as propagation both by seeds and vegetative reproduction. Replacement series experiments were used to test the effects of nutrient availability and competitive interaction on the growth performance of two clonal plant species. The experimental treatments included five nutrient levels (3.6, 7.2, 10.8, 14.4 and 18.0 kg organic matter per pot, 20 cm diameter and 15 cm deep) and five species proportions (20:0, 16:4, 10:10, 4:16 and 0:20 for L. chinensis and P. communis, respectively) with twenty tillers in total per pot. Each treatment had 10 replications. Growth characteristics including tiller height, tiller number, plant biomass, rhizome length and bud number of plants in monoculture and mixture culture were recorded and compared to examine the effects of nutrient and competitive interaction on the plant performance. The growth of L. chinensis and P. communis in mixture was influenced by the nutrient availability and competition, which depended on the combination between nutrient level and species proportion. The results implied that the intensity of competition should be lower in nutrient-poor habitats when the co-existing species demanded on the same limiting resource. P. communis benefited from coexisting with L. chinensis, especially under nutrient-rich conditions. The aboveground relative yield (RYabove) expressed in units of tiller height, dry biomass and daughter tiller number was recommended as an effective and simple index to predict the relative competitive ability for clonal plants. It was based on the regression for RY above and RYbelow (the belowground relative yield) against RY (relative yield), measured as yield in mixture divided by that in monoculture.
6

The ecological profit in phenology and pollination of alien species Spartina alterniflora [Loisel] introduced to coastal wetlands in Northern China

67%
Shi F., Yuan Z., He K. S., Li J., Guo S.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 2
283-289
For the plant species, effective phenology and pollination syndromes can increase viable seeds which enhance the species to colonize new areas. So the species with a suit of advantageous characteristics inherent in its reproductive ecology is critical to its dispersion. Spartina alterniflora – a perennial grass native to coastal marshes of America was introduced to China in 1979 and now it is distributed in the Tianjin coastal wetlands of northern China. Flowering phenology was examined and indicated that in northern localities, flowering initiated in mid-August and senescence occurred by the end of October. The pollen-ovule ratio was 9875 (±2150). Abundant pollen grains compensated for a lack of pollen viability. Pollen viability was 10% approximately when pollen released 4 hours, but stigma receptivity was above 10% when stigmas exserted 7 hours. Stigmas maintained viability longer than the period of pollen release, ensuring successful pollination. Scanning electron microscopy was used to observe stigma surface characters and pollen viability. Further investigation proved stigma adaptations to increase pollen capture and exterior pollen tube growth following pollination was beneficial to fertilization. The results suggested that flowering phenology and pollination traits are vital to pollination and production of viable seed, enabling the species to spread rapidly and succeed in new habitats of northern China.
7

Tillage options to control Cynodon dactylon in maize crops in semi-arid Zimbabwe

67%
Twomlow S. J., Riches C., Mabasa S., Nyahunzvi S.
Bibliotheca Fragmenta Agronomica
|
1997
|
tom 2B
8

Water runoff and soil erosion control in crop rotations

67%
Pabat I. A.
Bibliotheca Fragmenta Agronomica
|
1997
|
tom 2B
9

Wpływ nawożenia organicznego na wybrane cechy agronomiczne traw wieloletnich wskazanych dla rolnictwa tradycyjnego i ekologicznego

51%
Czembor E.
Biuletyn Instytutu Hodowli i Aklimatyzacji Roślin
|
2013
|
nr 270
10

Mikoryza Miscanthus x giganteus na terenie o podwyższonej zawartości Cd, Zn i Pb w podłożu

51%
Gucwa-Przepiora E., Sas-Nowosielska E., Kucharski R., Kita A., Malkowski L.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
2010
|
tom 545
Określono status mikoryzowy Miscanthus х gigantem Greef et Deuter - azjatyckiego gatunku wieloletniej trawy uprawianej obecnie do celów energetycznych. Miskanta uprawiano na terenie zanieczyszczonym Cd, Zn i Pb w Bytomiu oraz na poletku kontrolnym w Katowicach. Na wszystkich poletkach badawczych w korzeniach miskanta stwierdzono obecność struktur typowych dla mikoryzy arbuskularnej. Nie zaobserwowano różnic w poziomie kolonizacji mikoryzowej pomiędzy poletkiem kontrolnym a poletkami zanieczyszczonymi metalami. Kumulacja Cd, Zn i Pb w pędach i korzeniach miskanta rosła wraz z ich całkowitą zawartością w glebie. W większości przypadków wyższe zawartości metali odnotowywano w korzeniach niż w pędach.
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