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Here we define a “biogeochemical niche” characterized by the species position in the multivariate space generated by its content not only of macronutrients like N, P or K, but also of micronutrients such as Mo, Mg and Ca, and trace toxic elements such as Pb and As. We then hypothesize that the flexibility of the species “biogeochemical niche” will influence the quality of plant tissue, which may have implications for herbivores, and will affect the species capacity to respond to disturbances and climate change and to adapt to the new climate conditions. We show with a simple multivariate procedure, a principal component analysis (PCA), first, that there is a strong differentiation in the total and relative (stoichiometry) content of the different elements in coexisting plant species, and, second, that there is species-specific plasticity in the response of this elemental composition to experimental climate change. The concentrations of foliar macro and micronutrients, as well as trace elements were measured in several tree species (Quercus ilex L., Phillyrea latifolia L. and Arbutus unedo L. in a Mediterranean broad leaf forest (Prades Mts) and in shrub species (Erica multiflora L., Globularia alypum L. and Dorycnium pentaphyllum Scop.) in a Mediterranean shrubland (Garraf Mts) in control plants and in plants grown in experimental drought and warming plots. The climate conditions were monitored during the period 1999–2005. During this period, in the Prades experiment the drought plots had on average a soil moisture content 9% lower than the control plots, whereas in the Garraf experiment the drought treatment led to a mean reduction in soil moisture of 21% and the warming treatment to 0.9ºC rise. The species with greater changes in biogeochemical niche under increased warming or drought, Arbutus unedo, Erica multiflora and Globularia alypum, were those that were also more affected in growth, photosynthetic capacity and other eco-physiological traits. The species differentiations indicate a strong biogeochemical niche, and that the changes in biogeochemical niche are probably an underlying factor in community structure shifts.
Black elder is a deciduous shrub widely used in medicine, pharmacy and food industry. This study presents a comparison of the elemental composition of fruits (berries) from the Black elder (Sambucus nigra L.) cultivars Albida, Bohatka, Dana, Heidegg13, Mammut and Sambo, grown in the Czech Republic and harvested in two seasons (2011 and 2013). The fruits were collected at full maturity from an experimental orchard at the Research and Breeding Institute of Pomology, Holovousy Ltd. The raw material was decomposed using hot nitric acid and the determination of the elemental content (Ca, K, P, Zn. Cu, Mn, Na, Mg) was performed by inductively coupled atomic emission spectrometry in accordance with a valid ISO standard. Concentration of all the analyzed elements in the various Sambucus nigra cultivars was different, and the differences were statistically significant (p < 0.05). All the investigated cultivars were a good source of major and trace elements. The concentration of the analyzed elements in Sambucus nigra decreased in the following order K > Ca > P > Mg > Na > Fe > Mn > Zn > Cu. The results demonstrated that Sambucus nigra fruits can be used as functional food in prevention and treatment of diseases associated with deficiency of elements in the human diet. On average, 100 g of Sambucus nigra fruits can cover about 20% of the recommended dietary allowance of main elements for women and men. In terms of the content of individual elements, the cultivars Albida and Sambo have proven to be most promising. The chemical composition of Sambucus nigra varied with the year of harvest, but the variation in the elemental content did not exceed 20% in most cases.
Crab meat is an excellent source of minerals, particularly calcium, iron, zinc, potassium and phosphours. The minerals in the edible parts of muscle of C.lucifera different sexes (male, female and berried female) were determined by digital flame photometer. Totally 11 minerals are reported in the present study. Seven (Sodium> Potassium >Magnesium >Calcium>Manganese> Iron >Zinc) minerals were reported in all sexes. Sodium was maximum (137.55 mg) and zinc was minimum (1.76 mg) in all sexes. Copper, mercury and cadmium were available in trace amount in all sexes. However, arsenic was in trace amount in berried females and totally absent in males and females. Among different sexes, berried females contain maximum amount of minerals (156.24mg) followed by females (121.76 mg) and males (95.5mg).
Variation in vegetative and reproductive performance and leaf mineral composition among 25 populations of Colchicum autumnale (meadow saffron) from soils derived from six parent materials (limestone, marl, sandstone, greenstone, melaphyre and serpentine) in southwestern Poland has been investigated. The plant size (PS), total le-af area (TLA), leaf shape (LS), number of fruits per plant (NFP), number of seeds per plant (NFP), total weight seed per plant (TWSP) were estimated, and concentrations of seventeen elements (N, P, K, Ca, Mg, Na, S, Fe, Mn, Cu, Zn, Pb, Cd, Ni, Co, Cr, Mo) were analyzed in leaf and soil samples. In soil samples, also soil pH, organic matter content and sand, silt and clay content were determined. All soils (except melaphyre soil) contained elevated levels of Cr. Concentrations of soil Ni and Zn, Pb, Cd in serpentinite soil and polluted marl soils (respectively) were significantly higher than those of other examined soils. Meadow saffron leaves from all sites (except marl sites) contained elevated levels of Cr, Co and Ni. Statistical analysis, carried out with principal component analysis (PCA) revealed that a good correlation exists between the element content in leaves and plant performance traits and soil environment. The leaf Ca content and NFP were correlated and were much higher in populations from metal (except Cr) and nutrient-poor marl soils than in those from metal (except Ni in serpentine soil)and nutrient moderate rich soils derived from melaphyre, greenstones, serpentinite, limestones and sandstones and in those from metal-rich and nutrient-poor polluted marl soils. Meadow saffron plants tended to take up higher amounts of N, P, K, Mn, Cu and Na and lower amounts of S and had much higher TLA in populations from sandstone soils than those in populations from serpentinite, melaphyre, greenstone, marl and limestone soils. The leaf Co, Ni, Cr, Mg concentrations were correlated and were much higher in populations from serpentinite, melaphyre, greenstone, polluted marl and limestone soils than those from marl and sandstone soils. The pattern of variation in NFP and TLA across the different soil types was the opposite of that for leaf N, Cu, Na, Ni, Mg and S concentrations. Redundancy analysis (RDA) enables identification of the soil variables that best explain the variance pattern of plant response. The variation explained by the soil variables (15 soil elements and soil pH) was high (79%). The forward selection of soil variables identified soil Co, Mo, Ni, Ca and Zn concentrations as significantly influencing the ordination plant traits. The variation explained by these selected variables was 55%. Thus the five soil variables appeared to be the main factors determining the pattern variation of vegetative, reproductive and nutrient traits of Colchicum autumnale.
Celem pracy była ocena zawartości wybranych pierwiastków (Ca, Mg, Cu, Fe, Mn i Zn) w różnych rodzajach czekolad. Analizie poddano 20 czekolad, w tym: białe (B), mleczne (M) i gorzkie (G) o różnej zawartości masy kakaowej. Pogrupowano je według zawartości suchej masy kakaowej następująco [%]: G6 – 60, G7 – 70, G8 – do 85, G9 – 90. Suchą masę w próbkach oznaczono metodą suszarkowo-wagową. Oznaczenie zawartości Ca, Mg, Cu, Fe, Mn i Zn wykonano metodą płomieniowej atomowej spektrometrii absorpcyjnej (F-AAS) przy użyciu spektrometru AAS-3 Carl-Zeiss po uprzedniej mineralizacji próbek techniką spopielenia w piecu muflowym. Zaobserwowano istotnie większą zawartość Mg, Fe, Zn, Mn oraz Cu w czekoladach gorzkich w porównaniu z czekoladami mleczną i białą. Zawartość tych pierwiastków była tym większa, im większy był udział kakao w czekoladzie. W czekoladach gorzkich zawartość magnezu wynosiła 1545,40 ÷ 2862,55 μg/g s.m. Wykazano także znaczne ilości cynku (356,70 ÷ 511,35 μg/g s.m.) i żelaza (127,47 ÷ 155,74 μg/g s.m.), a mniejsze – miedzi (16,49 ÷ 25,37 μg/g s.m.) i manganu (15,85 ÷ 21,46 μg/g s.m.). Z kolei w czekoladach mlecznych i białych przeważał wapń, którego zawartość wahała się w granicach 3396,21 ÷ 4313,44 μg/g s.m. Czekolady gorzkie o większej zawartości suchej masy kakaowej mogą być dobrym źródłem Mg, Fe, Zn oraz Mn i Cu w diecie. Natomiast znaczącymi nośnikami wapnia mogą być czekolady białe i mleczne.
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