Search

Abstract Studies of in situ plant response and adaptation to complex environmental stresses, are crucial for understanding the mechanisms of formation and functioning of ecosystems of anthropogenically transformed habitats. We study short- and long-term responses of photosynthetic apparatus (PSA) and anti-oxidant capacity to complex abiotic stresses of common plants Calamagrostis epigejos and Solidago gigantea in semi-natural (C) and heavy metal contaminated habitats (LZ). We found significant differences in leaf pigment content between both plant species growing on LZ plots and their respective C populations. The average values of leaf chlorophyll indexes were 27% lower in the LZ populations of both species and significantly lower in Sg plants in comparison to Ce ones. The average values of the anthocyanin index in CeLZ and SgLZ populations were significantly higher (by 18%) than in their respective controls. In both Ce and Sg plants occurring on LZ plots, the average leaf flavonol indexes were higher than on their controls by 31% and 15% and this index was significantly higher in SgLZ population than CeLZ and CeC plants (by 34% and 54%, respectively). Both Ce and Sg populations growing on LZ plots showed significantly lower photosynthetic rate (A), transpiration rate (E) and stomatal conductance (g s ) in comparison to controls. On the other hand, a significantly higher photosynthetic rate was detected in SgLZ than in CeLZ populations. The catalase activities were significantly higher than recorded in Sg than in Ce tissues, irrespective of the plot type. They were also higher in LZ populations than those in controls for both species. Moreover, the H2O2 content in Sg tissues was significantly higher than those in Ce. Hydrogen peroxide content in CeLZ and SgLZ were respectively 39% (non-significant) and 57% higher, compared to their controls. The reverse pattern was found in the case of MDA, whose concentration was significantly higher in the leaves of Ce population compared to the control population. The average MDA concentration in CeLZ populations was 17% higher than in the CeC. In the case of Sg no significant differences were found. Mechanisms of plant species adaptation to industrial areas are crucial for species selection and planning effective reclamation of them. The analysis of chlorophyll fluorescence induction curves as well as well as the results of JIP test revealed the decreased of Fj value despite positive ΔK–band in SgLZ and CeLZ plants suggesting the increased rate of electron transfer from QA to QB at the acceptor side of PSII, thus a high quantity of P680+ and/or effective quenching by exogenous molecules. The increase in the I–P part of the induction curve typically attributed to the reduction of electron transporters (ferredoxin, intermediary acceptors, and NADP) of the PSI acceptor side was observed in both SgC and SgLZ but not in CeLZ populations. These changes demonstrate species-specific effects on electron transport during the light phase of photosynthesis under complex environmental stress. Our results show that Sg and Ce individuals developed a range of structural and functional adaptations to protect PSA against complex environmental stresses (possible combination of heavy metals, water deficiency, temperature, nutrient deficiency and salinity). Both species from LZ plots could tolerate high levels of Cd, Zn and Pb in leaf tissues. Therefore they can be potential candidates for use in phytoremediation of HM contaminated areas. However, further long-term field and experimental research on plant traits response and adaptation to complex environmental stresses on industrial habitats are needed.

Determining the level of solid pollution in beach sands located near artificial inland water bodies in order to maintain high safety standards is a difficult and expensive task. The tests aimed at determining beach pollution caused by solid wastes through analysis of toxic and chemical concentrations, are time-consuming and usually require several days before the results are available. In addition, the maintenance of the beach area involving beach raking or grooming, and the seasonal replenishment of sand makes it difficult to realistically determine the chemical or bacterial contamination of the tested material. Solid pollutants, such as glass, caps, cans, thick foil, metal, and plastic fragments, pose a greater health risk to beachgoers. The above-mentioned pollutants, especially small ones, are hardly visible on the surface or they are buried at shallow depths. Beach garbage poses a serious threat that can lead to infections from cuts and scratches. These injuries can become infected, further jeopardizing the health and lives of beachgoers due to risks like tetanus, staphylococcus, etc. The authors presented a new petrographic method aimed at assessing the quality of sand by examining the content of solid pollutants. The obtained results allowed us to conclude that the mentioned procedure can be used for a quick quantitative estimation of the content of potentially dangerous and undesirable pollutants in beach sands. Consequently, the method implemented to determent the amount of solid pollutants in beach sands has proven to be a valuable tool for recreational facility administrators, helping them in taking necessary measures to ensure the safety of beach users. Petrographic analysis of beach sands revealed the presence of pollutants of plant origin (0.4–1.8%), plastic (0.1–0.4%), paper (0.1–0.6%), charcoal (0.1–0.5%), glass (0.1–0.4%), metals (0.1–0.4%), rust (0.1–0.3%), ash and slag (0.1–0.3%), and fossil coals (0.1–0.2%).

W niniejszej pracy zestawiono środowiskowy i prawny aspekt rozwoju zielonej infrastruktury na terenach miejskich, ze szczególnym uwzględnieniem dachów zielonych. Wykazano, że zarówno istniejąca zielona infrastruktura, obejmująca parki, obszary chronione, lasy, pola itd., jak i kreowana de novo, np. w postaci dachów zielonych, minimalizuje skutki zmian klimatu i jest kluczowa dla zrównoważonego rozwoju. Zidentyfikowane korzyści płynące z wprowadzania dachów zielonych to m.in.: oszczędność energii, poprawa jakości powietrza i wody, wspieranie renaturyzacji miast i wzrost różnorodności biologicznej, które łącznie sprzyjają polepszeniu jakości życia w miastach. Dlatego też wskazano potrzebę usankcjonowania rozwoju zielonej infrastruktury na terenach miejskich w systemie prawnym. Dostrzegając aktualne zagrożenia środowiskowe oraz korzyści z zielonej infrastruktury, ustawodawca europejski podał wytyczne dotyczące jej tworzenia. W artykule dokonano przeglądu stanu prawnego i oceniono, w jaki sposób polityka Unii Europejskiej została zaimplementowana do wspólnotowego oraz krajowego porządku prawnego. W szczególności zbadano, w jakim zakresie organy samorządu terytorialnego uwzględniają zieloną infrastrukturę w miejscowych planach zagospodarowania przestrzennego.

Using local wild plant resources to create green roofs in urban areas is a sustainable solution that supports cities' adaptation strategies to climate change. Creating extensive green roofs, in accordance with the Nature-Based Solutions concept, supports minimizing the effects of climate change, loss of biodiversity and human health. The aim of this paper is to identify, based on an analysis of published research results, the main criteria for selecting vegetation introduced to green roofs and the role of green roofs in minimizing the effects of climate change in the context of NBS. The data were collected by analyzing the results of studies published in the last 10 years, focusing on plant selection. It was found that species selection often fails to consider plant functional traits. The potential of wild plants in urban-industrial areas for creating green infrastructure and optimizing ecosystem services remains largely unrecognized. However, certain plants with desirable functional traits, originating e.g. from habitats such as post-industrial coal mining waste heaps, show promise in providing functional support to urban ecosystems in minimizing the effects of climate change.

Abstract Perennial ryegrass is a grass species used to establish lawns in urban areas where pollution is a major environmental problems. Cadmium (Cd) and nickel (Ni) contribute significantly to these pollutants and may cause photosynthetic limitation. The main objective of this work was to perform a comprehensive analysis of photosynthetic efficiency of perennial ryegrass seedlings under Cd and Ni stress. Some of the main indices of photosynthetic efficiency (prompt and delayed chlorophyll-a fluorescence signals and modulated reflectance at 820 nm) were compared with growth parameters. Two cultivars were tested: 'Niga' and 'Nira'. A decrease in photosystem (PS) II and PSI activity was observed. This was due to an increase in nonradiative dissipation of the PSII antenna, a decrease in PSII antenna size, or a decrease in the number of photosynthetic complexes with fully closed PSII RCs. Efficiency of electron transport was decreased. The effect on the modulated reflectance signal could indicate a restriction in electron flow from PSII to PSI. The correlation between photosynthetic efficiency parameters, such as Area, Fo, Fm, and Fv, and growth parameters, confirmed that some photosynthetic efficiency parameters can be used as indicators for early detection of heavy metal effects.

Abstract Identifying environmental factors that improve plant growth and development under nitrogen (N) constraint is essential for sustainable greenhouse production. In the present study, the role of light intensity and N concentrations on the biomass partitioning and physiology of chrysanthemum was investigated. Four light intensities [75, 150, 300, and 600 µmol m−2 s−1 photosynthetic photon flux density (PPFD)] and three N concentrations (5, 10, and 15 mM N L−1) were used. Vegetative and generative growth traits were improved by increase in PPFD and N concentration. High N supply reduced stomatal size and gs in plants under lowest PPFD. Under low PPFD, the share of biomass allocated to leaves and stem was higher than that of flower and roots while in plants grown under high PPFD, the share of biomass allocated to flower and root outweighed that of allocated to leaves and stem. As well, positive effects of high PPFD on chlorophyll content, photosynthesis, water use efficiency (WUE), Nitrogen use efficiency (NUE) were observed in N-deficient plants. Furthermore, photosynthetic functionality improved by raise in PPFD. In conclusion, high PPFD reduced the adverse effects of N deficiency by improving photosynthesis and stomatal functionality, NUE, WUE, and directing biomass partitioning toward the floral organs.

Due to advances in the industrial development of light-emitting diodes (LEDs), much research has been conducted in recent years to get a better understanding of how plants respond to these light sources. This study investigated the effects of different LED-based light regimes on strawberry plant development and performance. The photosynthetic pigment content, biochemical constituents, and growth characteristics of strawberry plants were investigated using a combination of different light intensities (150, 200, and 250 μmol m−2 s−1), qualities (red, green, and blue LEDs), and photoperiods (14/10 h, 16/8 h, and 12/12 h light/dark cycles) compared to the same treatment with white fluorescent light. Plant height, root length, shoot fresh and dry weight, chlorophyll a, total chlorophyll/carotenoid content, and most plant yield parameters were highest when illuminated with LM7 [intensity (250 μmol m−2 s−1) + quality (70% red/30% blue LED light combination) + photoperiod (16/8 h light/dark cycles)]. The best results for the effective quantum yield of PSII photochemistry Y(II), photochemical quenching coefficient (qP), and electron transport ratio (ETR) were obtained with LM8 illumination [intensity (250 μmol m−2 s−1) + quality (50% red/20% green/30% blue LED light combination) + photoperiod (12 h/12 h light/dark cycles)]. We conclude that strawberry plants require prolonged and high light intensities with a high red-light component for maximum performance and biomass production.

Abstract Knowledge about biotic (plant species diversity, biomass) and/or abiotic (physicochemical substrate parameters) factors that determine enzyme activity and functional diversity of the substrate on hard coal spoil heaps is limited. Spontaneously developed vegetation patches dominated by herbaceous species commonly occurring on these spoil heaps: grasses (Poa compressa, Calamagrostis epigejos) and forbs (Daucus carota, Tussilago farfara), were examined. The activity of dehydrogenase and alkaline phosphatase was twice as high in plots dominated by grass species compared with those dominated by forbs. Significant positive correlations were found between the activity of dehydrogenase and alkaline phosphatase with pH, available P, soil moisture, and water holding capacity and negative correlations between the activity of urease and soil organic carbon. Strong positive correlations were found between values for Shannon–Wiener diversity index, evenness, species richness and soil functional diversity in plots dominated by grasses. We found that the soil physicochemical parameters had a greater impact on enzyme activity of the substrate than plant biomass and species diversity. However, grasses, through their extensive root system, more effectively increased enzyme activity and health of the substrate than other herbaceous species, and as they stabilize the substrate and form dense plant cover, they can be recommended for reclamation purposes.

Pesticide use cannot be completely abandoned in modern agriculture. Among agrochemicals, glyphosate is one of the most popular and, at the same time, most divisive herbicide. Since the chemicalization of agriculture is detrimental, various attempts are being made to reduce it. Adjuvants—substances that increase the efficiency of foliar application—can be used to reduce the amount of herbicides used. We propose low-molecular-weight dioxolanes as adjuvants for herbicides. These compounds quickly convert to carbon dioxide and water and do not harm plants. The aim of this study was to evaluate the efficacy of RoundUp® 360 Plus supported by three potential adjuvants: 2,2-dimethyl-1,3-dioxolane (DMD), 2,2,4-trimethyl-1,3-dioxolane (TMD), and (2,2-dimethyl-1,3-dioxan-4-yl)methanol (DDM), on a common weed species Chenopodium album L., under greenhouse conditions. Chlorophyll a fluorescence parameters and analysis of the polyphasic fluorescence (OJIP) curve, which examines changes in the photochemical efficiency of photosystem II, were used to measure plant sensitivity to glyphosate stress and verified the efficacy achieved by tested formulations. The effective dose (ED) values obtained showed that the weed tested was sensitive to reduced doses of glyphosate, with 720 mg/L needed to achieve 100% effectiveness. Compared to the glyphosate assisted with DMD, TMD, and DDM, ED was reduced by 40%, 50%, and 40%, respectively. The application of all dioxolanes at a concentration equal to 1 vol.% significantly enhanced the herbicide’s effect. Our study showed that for C. album there was a correlation between the change in OJIP curve kinetics and the applied dose of glyphosate. By analyzing the discrepancies in the curves, it is possible to show the effect of different herbicide formulations with or without dioxolanes at an early stage of its action, thus minimizing the time for testing new substances as adjuvants.

Satureja khuzistanica Jamzad is a valuable and endemic medicinal plant. Boron and zinc are essential elements for the vegetative and reproductive growth of plants and have significant effects on yield, essential oil composition and the seed production of plants. To investigate the effects of the foliar application of zinc and boron on the growth, yield, seed production and phytochemical properties of S. khuzistanica, a study was conducted in a factorial experiment with three replicates in two consecutive years based on a randomized complete block design. The foliar application of boron (B) at three concentrations (control or distilled water, 0.4% and 0.8% as H3BO3) and zinc (Zn) at three concentrations (control or distilled water, 0.3% and 0.6% as ZnSO4) was carried out. Our results showed that the foliar application of B resulted in a significant increase in the fresh and dry weights of plants, the dry weight of stems, drug yield, seed yield, seed germination and 1000-seed weight. At the same time, the application of B resulted in a significant decrease in seed emptiness. The fresh and dry weights of plants, drug yield, seed yield, 1000-seed weight and seed germination were also significantly improved by Zn foliar spraying compared to the control. Application of 0.8% B resulted in a significant decrease in seed emptiness by 14.16% and 22.37%, as compared to the control. The foliar spraying of B and Zn improved the total phenolic content, the essential oil content and the yield and antioxidant activity of S. khuzistanica. Moreover, B application generally concentrated more carvacrol in the essential oil (in the first experimental year). In contrast, no significant differences were observed between Zn treatments in carvacrol content and total flavonoids. The use of several microelements, such as B and Zn, could improve both the quantity and quality of S. khuzistanica. Additionally, improvement of seed set and seed quality by the foliar spraying of Zn and B may be useful for growing plants in arid and semi-arid areas.

GABA (gamma-aminobutyric acid) and melatonin are endogenous compounds that enhance plant responses to abiotic stresses. The response of Vicia faba to different stressors (salinity (NaCl), poly ethylene glycol (PEG), and sulfur dioxide (SO2)) was studied after priming with sole application of GABA and melatonin or their co-application (GABA + melatonin). Both melatonin and GABA and their co-application increased leaf area, number of flowers, shoot dry and fresh weight, and total biomass. Plants treated with GABA, melatonin, and GABA + melatonin developed larger stomata with wider aperture compared to the stomata of control plants. The functionality of the photosynthetic system was improved in primed plants. To investigate the photosynthetic functionality in details, the leaf samples of primed plants were exposed to different stressors, including SO2, PEG, and NaCl. The maximum quantum yield of photosystem II (PS II) was higher in the leaf samples of primed plants, while the non-photochemical quenching (NPQ) of primed plants was decreased when leaf samples were exposed to the stressors. Correlation analysis showed the association of initial PIabs with post-stress FV/FM and NPQ. Stressors attenuated the association of initial PIabs with both FV/FM and NPQ, while priming plants with GABA, melatonin, or GABA + melatonin minimized the effect of stressors by attenuating these correlations. In conclusion, priming plants with both GABA and melatonin improved growth and photosynthetic performance of Vicia faba and mitigated the effects of abiotic stressors on the photosynthetic performance.