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The Cu and Ni contents in aboveground biomass of oats (Avena sativa L.) used for haylage making were studied in the two-year pot experiment, which included five variants: control (not fertilised), NPK, farmyard manure, compost from Krakow and compost from Červený Újezd (Tab. 2 and 3). The final nutrients dose was IS g N, 1,1 g P and 1.75 g K-pot-1. Fertilisers were applied at one before sowing in 2001, and in the second year only 0.75 g N was added to all pots as ammonium nitrate. In 2001 the highest yield of aboveground oats biomass was obtained after mineral NPK fertilisation (Fig. 1). A significantly higher yield was noted also when compost from Červený Újezd was applied. In 2002, the biomass yields in all fertilised variants were uniform and significantly higher than in the control, and the highest yield was obtained after compost from Krakow application. In 2001, the highest Cu and Ni content in the aboveground oats biomass were found after mineral NPK application (Fig. 2 and 3). In the second year, Cu content was similar in all dressed variants and significantly higher than in control plants, and the Ni content was almost identical. The both elements contents did not exceed limits acceptable for dry feeds.
A vailability and heterogeneity of resources have a strong influence on community biomass and diversity, which provided a valuable opportunity to evaluate the responses of vegetation on fertilization, to test whether fertilisation can accelerate vegetation restoration in infertile lands. In loess hilly region of China, most newly abandoned infertile lands often undergo heavy soil erosion. It is urgent to promote the restoration of these types of lands. As availability and heterogeneity of soil nutrients have a strong influence on plant community, we conducted a fertilisation experiment with three-factor treatments, to test whether fertilisation can promote the biomass and species richness of an Artemisia scoparia-dominated old field community. The three factors were: spatial patterns (homogeneity and heterogeneity), levels (low, medium and high), and scales (three levels with small, intermediate, and large patches) of fertiliser application. Aboveand below-ground biomass and species richness were recorded. The responses of the plant community to the three factors were evaluated and compared with those of the control (no fertilisation). The results show that: (1) The application of fertiliser in either homogeneous or heterogeneous pattern significantly increased the above-ground and below-ground biomass of the plant community as compared with the control. (2) In heterogeneous conditions, the above-ground biomass in nutrient-rich patches was significantly greater than the expected value of 50%. Under intermediate and large scales of the low level and all scales of the medium and high levels, the proportion of 0–15 cm below-ground biomass was also significantly greater than 50%. (3) Both homogeneous and heterogeneous fertilisation greatly increased community richness as compared to the control. Fertilisation, particularly heterogeneous fertilisation, can effectively increase community biomass and diversity. Under patchy habitat, it seems that the responses of vegetation to heterogeneous fertilisation are related to the patches scale and the contrast among patches, nutrient usage efficiency, edge effects on plant and soil, and plant competition are responsible for the responses. The results also suggest that heterogeneous fertilisation should be applied widely in infertile old fields to accelerate secondary succession.
Voronoi area of coexisting species in a community has an important role in determining their performances as it is related with the available resources around individuals. Biomass formed within certain Voronoi area probably can be a mark of species that characterised resource competition ability of coexisting species in natural community. In this article, we tried to probe the subject in the following three aspects: 1) what is the apparent relationship between individuals’ aboveground biomass and their available Voronoi area for species in natural community? 2)what is the possible theoretic relationship between them? 3) additionally, whether there are any possible indices that can be elicited from species’ occupied Voronoi area to reflect species’ competitive ability. Using individual-based investigation of aboveground biomass and their corresponding positions, Voronoi area of all individuals of coexisting species in an old field community were computed. The growth of an individual could be regard as a process to compete for resources that is limited by the available area or volume encompassed by the neighborhood individuals. We extended logistic growth model to describe the relationship between Voronoi area and aboveground biomass of coexisting species by relating limiting rhizospheral resource with the Voronoi area around an individual. Theoretically, the individual’s aboveground biomass is also controlled by factor-ceiling effects of Voronoi area. So the extended model was fitted with boundary analysis method. And also, their linear relationship was fitted. Under the prediction that competive ability is one of the main driving factors of community succession, two parameters as the Voronoi area of coexisting species and the Voronoi area per unit of aboveground biomass were used to check whether they can designate species’ competitive abilities and competitive hierarchies. This was presented by fitting the two parameters with the successional niche positions that was represented by the ordination values along abandonment ages of old field communities in the local area. The results showed that: 1) For most species, the linear regression demonstrated that Voronoi area of an individual that occupied larger Voronoi area tended to have greater aboveground biomass. The nonlinear regression of showed that the relationship might depend upon species’ growth characteristics, like shade tolerance and root proliferation. Generally, the relationship could be better fitted by the extended logistic growth model using boundary analysis method than by the linear regression, except for some shade-preferring or clone species. If factor-ceiling effects were considered, at the highest, about 48% of the variation of aboveground biomass could be interpreted by Voronoi area. For some other species with light preference or clone proliferation, the determination coefficient was around zero. 2) Species’ averaged Voronoi area had significant and positive Kendall’s tau-b and Spearman correlations with successional niches, and species’ per-unit aboveground biomass positions of Voronoi area has significantly negative rank correlation with successional niche positions. These indicate that both of them can reflect species’ competitive ability and hierarchy to some extent.
We studied the relationship between tree-species diversity and the above-ground biomass on an example of two natural Polish forest with different altitiudinal range, plant species pool, vegetation and climatic conditions. The study sought to determine whether: (1) above-ground biomass in natural forests correlates with tree-species diversity irrespective of the kind of forest (montane or lowland), and (2) the relationship in question is negative, (3) the above-ground biomass is greater in montane forests than in lowland ones. Natural forests present in 1º Polish Gorce Mountains (montane forest) alongside comparable data for the 2º world-renowned lowland forest that is present in the Białowieża National Park. Data were collected within 558 sample plots (á 200-square-metre). The diameter at breast height of all trees with girths of or exceeding 12 cm was measured. To compute above-ground biomass we calculated dry masses for each tree on the basis of values for dbh and height, next we summed these values for all species present within each plot. The number of tree species on a plot ranged from only one (mainly in spruce stands) to six (in mixed deciduous lowland forest stands). The above-ground accumulated biomass ranged from 6 to 1155 (average 251±13) t ha–1 within the lowland forest, and from 2 to 849 (average 242±8) t ha–1 within the montane forest. We concluded that there was a humped-back shaped relationship between tree-species diversity and above-ground biomass in both lowland and montane natural forests.
It is not clear to what extent trees growing on anthropogenic sites change their growth and biomass allocation to different organs. We assessed the aboveground biomass in a chronosequence of six Scots pine monocultures (between 6 and 20 years old) to examine how precisely the site-specific or control allometric equations may reflect the value of biomass accumulation and allocation in stands growing in harsh site conditions on the overlayer spoil heap made as a result of opencast brown coal mining. The site is characterized by poor edaphic and water conditions and nutrient deficiency. The control equations were developed from Scots pine stands growing on post-agricultural lands in the close vicinity of the spoil heap. We found that equation type significantly influenced results of predicted biomass accumulation for all biomass components studied (although results were only marginally significant for total aboveground biomass, P=0.08). Total aboveground biomass in younger stands (6–9 years old) estimated using site-specific equations was >40% higher and for older stands (17–20 years old) from 7 to 27% lower than estimated using equations developed for the control sites. Our study revealed that under harsh environmental conditions in spoil heaps, biomass of young Scots pine stands significantly differ from values calculated based on control equations developed for more fertile soils with better water conditions in the same region. The control biomass equations may not be suitable to estimate biomass accumulation in stands growing on infertile habitats with poor water conditions, if the control equations are developed for nearby stands but growing under better site conditions.
Theoretical and field studies on seed size and plant abundance relationship have been conducted in various communities. However, inconsistent patterns have emerged from these studies, and still little is known about alpine meadows. Here we identified four models and their predictions: the seed size/number trade-off model (SSNTM), the succession model (SM), the spatial competition model (SCM), and the triangle model (TM), in order to assess the relationship between seed size and abundance in alpine meadows, and to elucidate underlying mechanisms. The study site was situated on the eastern Qinghai-Tibetan Plateau at 3500 m above sea level. From 1999 through 2001, two indices of plant abundance (aboveground biomass and density) were simultaneously measured in 45 quadrates (0.25 m²). Data for 101 plant species (mostly Cyperaceae, Poaceae, Asteraceae, Ranunculaceae and forbs) showed that seed size is like log normal distributed, and it slightly skewed in smaller-sized seeds. The SSNTM, the TM, the SM and the SCM models were not supported in this alpine meadow, and the relationship between seed size and abundance was always positive (although in some samples, the relationship was not significant). The positive correlation between seed size and abundance observed for some grassland communities was also demonstrated in the alpine meadow. It suggests that seed size depends on the plant growth form, but the biomass-density relationship is inconsistent with previous studies. This suggests that the measure of abundance used in these studies is not the only reason for inconsistency of seed size.
The study was carried out in 39- and 43-year-old stands of noble fir (Abies procera Rehder) grown in the Rogów Arboretum of the Warsaw University of Life Sciences (Poland). The main objectives of our study were (1) to estimate stem volume over bark of noble fir grown out of its natural range, (2) to develop suitable allometric equations for estimating aboveground woody biomass components and (3) to estimate aboveground woody biomass components using site-specific allometric equations and to compare them with biomass estimated using allometric equations developed in stands grown within natural range of noble fir. The study showed that the mean DBH of trees was 20.14 cm in the younger stand and 22.25 cm in the older stand. The basal area of the 39-year-old stand was 49.01 m2·ha-1 and 43-year-old stand was 47.53 m2·ha-1. Based on the developed equation stem volume over bark was 374.87 m3·ha-1 and 356.24 m3·ha-1 in the 39- and 43-year-old stands, respectively. Based on the developed site-specific allometric equations total aboveground woody biomass in the 39-year-old stand was 189 Mg·ha-1 whereas in the 43-year-old stand it was 184 Mg·ha-1. Branch biomass in both stands equaled 19.9% of total aboveground wood biomass. Total aboveground woody biomass, estimated by allometric equations published by Ter-Mikaelian and Korzukhin [1997], equaled 233 Mg·ha-1 and 228 Mg·ha-1 in the 39- and 43-year-old stands, respectively. This means that the aboveground woody biomass is overestimated by ca. 23% in comparison with biomass estimated by our site-specific allometric equation. Generally, the existing equations published by Ter-Mikaelian and Korzukhin [1997] overestimated total aboveground woody biomass and stem biomass, while branch biomass was underestimated across all tree sizes compared to directly obtained biomass data.
The aim of this study was to specify the above-ground biomass structure of black alder as well as to assess the influence of habitat conditions on biomass size and on allometric relation between biomass and breast height diameter. The empirical material consisted of 67 sample trees in age from 6 to 20 years selected from 17 stands growing on two types of forest habitat. The average share of stem wood in aboveground biomass of trees was 61.04%, branches 18.89%, bark and leaves 11.31% and 8.76% respectively. The fact that the examined stands constituted habitat type did not substantially influence either the biomass size or the relation between biomass and breast height diameter.
Activity of soil dehydrogenase (DHA) was measured in the mineral soil in a forest stand of 15 to 16-year-old Scots pine (Pinus sylvestris L.) from geographically diverse populations, as an indicator of biological activity of soil microorganisms, in a provenance experiment in Poland. The pine populations originated from six European countries (Sweden, Russia, Latvia, Poland, Germany, France) and differed widely in aboveground biomass and productivity. Soil DHA during two growing seasons showed pronounced seasonal variability, which was significantly related to the fine root concentration of nonstructural carbohydrates. Higher DHA was found in soil under canopies of the central and southern European populations than in those from more northern parts of the Scots pine range. Significant positive correlation between soil DHA and aboveground tree biomass suggest that these patterns most likely resulted from differences in carbon dynamics and productivity among populations.
Celem badań była ocena sposobu i terminu zakładania plantacji pokrzywy oraz określenie optymalnego terminu zbioru. Plantację założono sposobem wegetatywnym (z podziemnych kłączy) i generatywnym (wysiew nasion) w trzech terminach jesiennych (pierwsza dekada września, października i listopada 1991 r.) oraz wiosennym (pierwsza dekada kwietnia 1992 r.). Rośliny zbierano w trzech fazach rozwojowych: wegetatywnej (przed pąkowaniem), w pełni pąkowania i w pełni kwitnienia. Plantacja założona z kłączy zapewnia wyższe plony świeżej i suchej masy roślin niż z nasion. Optymalnym terminem wysadzenia kłączy jest wczesna jesień (pierwsza dekada września), zaś wysiewu nasion – późna jesień (listopad lub październik). Stwierdzono, iż wraz ze zbiorem roślin w późniejszych fazach rozwojowych notowano wyższe plony roślin, ale o mniejszym udziale liści.
Celem pracy było określenie wpływu zróżnicowanego udziału Medicago media Pers. w mieszance z Festulolium braunii (K. Richt.) A. na plon biomasy nadziemnej, plon białka oraz względną zawartość chlorofilu w liściach festulolium. Badania przeprowadzono w latach 2011- 2013. Ścisłe doświadczenie polowe zlokalizowano w Stacji Dydaktyczno-Badawczej Uniwersytetu Warmińsko-Mazurskiego w Olsztynie, na glebie mineralnej, klasy bonitacyjnej IVa, kompleksu żytniego bardzo dobrego. Badaniami objęto festulolium uprawianą w siewie czystym oraz w mieszance z lucerną mieszańcową. Czynnikiem doświadczalnym był zróżnicowany udział nasion lucerny w mieszance: 30, 50, 70%. Uzyskane wyniki wykazały, że udział lucerny w mieszankach systematycznie wzrastał w kolejnych latach badań, przy czym jej udział w biomasie nadziemnej był większy do ilości wysianych nasion. Wprowadzenie lucerny jako komponentu mieszanki spowodowało wzrost względnej zawartości chlorofilu w liściach festulolium, jednak między obiektami z 30 i 50% udziałem lucerny nie stwierdzono istotnych różnic. Mieszanki plonowały istotnie wyżej w stosunku do siewu czystego festulolium. W zależności od udziału lucerny w mieszance plonowanie było o ok. 40 do 46% większe i wierniejsze w latach badań. Wprowadzenie lucerny do mieszanki istotnie zwiększyło plon białka z jednostki powierzchni. W porównaniu do siewu czystego festulolium plon białka mieszanek wzrósł o ok. 61-80%. Wysoce istotne współczynniki korelacji dowodzą, że indeks zieloności liści można uznać za ważny wskaźnik prognozowania wielkości plonowania roślin oraz plonu uzyskanego białka.
W latach 2008–2010 wykonano doświadczenia na polu z piaskiem gliniastym lekkim, które miały na celu porównanie plonów świeżej i suchej masy nadziemnej i korzeni oraz oddziaływania antymątwikowego (Globodera rostochiensis) dziesięciu odmian gorczycy białej uprawianych w plonie głównym. Odmiany gorczycy białej różniły się istotnie plonem masy nadziemnej i korzeni oraz antymątwikowym oddziaływaniem. Największymi plonami świeżej i suchej masy części nadziemnej charakteryzowały się odmiany Accent, Concerta, Bardena i Radena, a w przypadku plonów korzeni – Accent, Radena, Bardena i Concerta. Poziom plonowania biomasy nadziemnej uzależniony był głównie od wysokości roślin. Ilości świeżej masy plonu ogólnego gorczycy białej stanowiły 51–71% średniej dawki obornika bydlęcego (35 t·haˉ¹), stosowanej pod ziemniaki. Uprawa wszystkich badanych odmian gorczycy białej ograniczała populację mątwika ziemniaczanego w glebie. Najsilniejszy efekt antymątwikowy wykazały odmiany Bardena, Rota, Accent, Sirola i Radena. Lata badań miały istotny wpływ na badane parametry plonowania. W 2010 roku, przy największym zagęszczeniu mątwika w glebie i najmniejszej masie korzeni gorczycy białej, stwierdzono najmniejszy efekt antymątwikowy.
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