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To date, the effect of habitat conditions on the characteristics of pollen has not been extensively investigated; however, it needs to be remembered that it may be highly significant for the quality of their generative reproduction success. It was decided to conduct the analyses on Convallaria majalis as a common species, naturally found in many different forest habitats. Moreover, the investigations covered pollen morphology and for the first time also the variability of pollen grains in this species. The plant material came from 98 natural sites located in Poland, in nine differing forest habitats. In total, 2940 pollen grains were analyzed in terms of five quantitative features (i.e., the length of the longest and shortest polar axes–LA and SA, exine thickness–Ex, the LA/SA and Ex/LA ratios) as well as the following qualitative ones: pollen outline and shape, sulcus type and exine ornamentation. Our studies revealed that the most important pollen characteristics in C. majalis included sulcus type, exine ornamentation, distribution and size of perforations, LA and pollen shape. The study showed the response of pollen to different habitat conditions found in the nine investigated habitats. The Ex/LA ratio and Ex were these pollen characteristics, which exhibited the most marked response to the different habitat conditions. Pollen from two habitats, moist mixed coniferous forest and upland mesic broadleaved forest, exhibited the most distinct characteristics.

The intensive use or discontinuation of the use of swards can compromise biodiversity, yields, and feed quality; thus, leading to the degradation of permanent grasslands. Various methods of renovation are employed to restore the usability of degraded swards. In the years 2013–2016, a monofactorial field experiment was carried out on the Experimental Farm in Grabów (province of Mazowieckie, Poland). The experiment involved swards being reseeded after ploughing (P) and after disking with a compact harrow (H), with a non-renovated sward as the control treatment. The plots under renovation were reseeded with a lucerne–grass mixture. Both seedbed preparation methods for the renewed sward, ploughing (P) or shallow disking to a depth of 5 cm (H), were found to be effective for increasing sward yields, restricting weed growth, and reducing the number of weeds in the sward. The ploughing-based renovation method (P) had a strongly restrictive effect on biodiversity, as expressed by the H’ function value vis-à-vis the harrow method (H) and the non-renewed control (NR). Dicotyledonous species accounted for 92.3% of the weed population in the studied treatments. Of these, Taraxacum officinale, Achillea milefolium, Capsella bursa-pastoris, and Plantago maior occurred in the highest numbers.

The importance of mineral elements, both in animal and plant nutrition, has been well recognized, but, in the case of sedges, the mineral composition is relatively poorly known. Studies usually relate to the content of the elements in sedge communities, or sward or hay communities with sedge participation, and rarely of Carex representatives. The objective of our study was to determine the concentrations of C, N, Ca, P, Mg, Na, K, Si, Cu, Zn, Mn, Fe, Cr and Ni in the biomass of 11 Carex species commonly occurring on natural sites of Central European lowland. Interspecific differentiations have been observed in concentrations of the major and trace elements among studied sedge species. The elemental composition of examined Carex species is diversified but generally similar to the composition of grasses. The study shows that sedges can increase fodder value and, therefore, they should be considered in meadow management as a valuable component of economically important meadow communities. Moreover, the data reported herein can be used for modelling the phytoaccumulation of various elements in the biomass of sedges. This will help in creating different patches suitable for obtaining adequate fodder. Our results can supplement current knowledge concerning the fodder value of meadows with sedge participation.