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EN
Temporal variation is a major source of the uncertainty in estimating the fluxes of the greenhouse gases (GHGs) in terrestrial ecosystems, and the GHG fluxes and its affecting factors in the karst region of southwest China remains weakly understood. Using the static chamber technique and gas chromatography method, the CO₂, CH₄ and N₂O fluxes were carried out between 9 and 11 a.m. at 15 day intervals from June 2008 to May 2009 in a Pinus massoniana forest. Two treatments were chosen for this study: undisturbed (soil with litter layer) and disturbed (surface litter removal). Both treatments were found to be the net source of atmospheric CO₂ and N₂O, but a sink of atmospheric CH₄. The seasonality of soil CO₂ emission coincided with the seasonal climate pattern, with high CO₂ emission rates in the hot-wet season and low rates in the cool-dry season. In contrast, seasonal patterns of CH₄ and N₂O fluxes were not clear, although higher CH₄ uptake rates were often observed in autumn and higher N₂O emission rates were often observed in spring (dry-wet season transition). The litter was active in GHG fluxes, and removal of the litter layer reduced soil CO₂ emission (17%) and increased CH₄ uptake (24%) whereas N₂O fluxes were not affected distinctly in the pine forest, indicating that litter layer had an important effect on C exchanges. In the pine forest, soil CO₂ emissions and CH₄ uptakes correlated significantly with soil temperature (r²= 0.87, P <0.01; r²= 0.34, P <0.05, respectively), but had no significant relationship with soil moisture. And there was a significant correlation between CH₄ flux and NH₄⁺-N (r²= 0.39, P < 0.05) and soil inorganic N (r²= 0.48, P <0.05), but no significant correlation was found between CH₄ flux and NO₃⁻-N. Moreover, we found a significant negative logarithmic correlation between N₂O flux and soil NO₃⁻-N concentration (r²= 0.41, P <0.05), and the relationship between CO₂ emission and soil inorganic N content (r²= 0.35, P < 0.05). These results suggested that soil temperature and mineral N dynamics largely affected the temporal GHG exchanges between forest soil and atmosphere.
EN
The reports of Intergovernmental Panel for Climate Change indicate that the growing emission of greenhouse gases, produced from the combustion of fossil fuels, mainly carbon dioxide, leads to negative climate changes. Therefore, the methods of mitigating the greenhouse gases emission to the atmosphere, especially of carbon dioxide, are being sought. Numerous studies are focused on so-called geological sequestration, i.e. injecting carbon dioxide to appropriate geological strata or ocean waters. One of the methods, which are not fully utilized, is the application of appropriate techniques in agriculture. The plant production in agriculture is based on the absorption of carbon dioxide in the photosynthesis process. Increasing the plant production directly leads to the absorption of carbon dioxide. Therefore, investigation of carbon dioxide absorption by particular crops is a key issue. In Poland, ca. 7.6 mln ha of cereals is cultivated, including: rye, wheat, triticale, oat and barley. These plants absorb approximately 23.8 mln t C annually, including 9.8 mln t C/yr in grains, 9.4 mln t C/yr in straw and 4.7 mln t C/yr in roots. The China, these cereals are cultivated on the area over 24 mln ha and absorb 98.9 mln t C/yr, including 55 mln tC/yr in grains, 36 in straw, and 7.9 mln t C/yr in roots. The second direction for mitigating the carbon dioxide emission into the atmosphere involves substituting fossil fuels with renewable energy sources to deliver primary energy. Cultivation of winter cereals as cover crops may lead to the enhancement of carbon dioxide removal from the atmosphere in the course of their growth. Moreover, the produced biomass can be used for energy generation.
PL
Z raportów Międzynarodowego Zespołu ds. Zmian Klimatu (IPCC) wynika, że rosnąca emisja gazów cieplarnianych, głównie dwutlenku węgla pochodzącego ze spalania paliw kopalnych, prowadzi do negatywnych zmian klimatu. Wobec takiego zagrożenia poszukuje się metod prowadzących do ograniczenia emisji do atmosfery gazów cieplarnianych, w szczególności dwutlenku węgla. Badania nad ograniczeniem emisji dwutlenku węgla koncentrują się głównie nad tzw. sekwestracją geologiczną, czyli zatłaczaniem dwutlenku węgla do odpowiednich pokładów geologicznych lub wód oceanicznych. Jednym ze sposobów, nie w pełni wykorzystanych, jest stosowanie odpowiednich technik w rolnictwie. Roślinna produkcja w rolnictwie oparta jest na absorpcji dwutlenku węgla w procesie fotosyntezy. Zwiększenie produkcji roślinnej prowadzi bezpośrednio do wzrostu absorpcji dwutlenku węgla. Dlatego ważnym zagadnieniem jest poznanie absorpcji dwutlenku węgla przez poszczególne uprawy. W Polsce na obszarze o powierzchni 7,6 mln ha uprawia się zboża: żyto, pszenicę, pszenżyto, owies i jęczmień. Rośliny te absorbują rocznie około 23,8 mln t C, z tego 9,8 mln t C/rok w ziarnach, 9,4 mln t C/rok w słomie i 4,7 mln t C/rok w korzeniach. W Chinach zboża te uprawiane są na powierzchni przekraczającej 24 mln ha i absorbują 98,9 mln t C/rok, z tego w ziarnach 55 mln t C/rok, w słomie 36 mln t C/rok, a 7,9 mln t C/rok w korzeniach. Drugim kierunkiem ograniczania emisji dwutlenku węgla do atmosfery jest zastępowanie paliw kopalnych, stanowiących źródło energii pierwotnej, przez odnawialne źródła energii. Uprawa zbóż ozimych jako roślin okrywowych może prowadzić do intensyfikacji usuwania dwutlenku węgla z atmosfery. Ponadto wyprodukowana biomasa może być wykorzystana jako surowiec do produkcji energii.
EN
An important question stated in the presented paper is: Could rotifers be the indicators of climate change in the Antarctic environments? Rotifers are one of the most important components of the invertebrate fauna of the Antarctic freshwater and terrestrial ecosystems. However, investigations of their distribution, diversity and an ecological role in the environment have been widely neglected, mainly due to the methodological and taxonomical difficulties. During the investigations 176 species of rotifers were found, including the endemic and cosmopolitan species. Their existence is directly proportional to microvariations of humidity factor. Scientists still have poor knowledge about the occurrence of rotifer species in recently studied habitats e.g. cryoconite holes, nunataks or soil. Probably rotifers could be the indicators of climate change in the Antarctic freshwater and terrestrial ecosystems but more investigations and monitoring studies are needed.
EN
In 72 samples collected from various types of habitats of West Spitsbergen 150 algal taxa have been identified, including 100 taxa of Cyanoprokaryota, 40 of Chlorophyceae, and 10 of Xanthophyceae. Seventy-two species, mainly blue-green algae (55 taxa) are considered as new for Svalbard flora.
EN
Colonization of terrestrial ecosystems by the first land plants, and their subsequent expansion and diversification, were crucial for the life on the Earth. However, our understanding of these processes is still relatively poor. Recent intensification of studies on various plant organisms have identified the plant cell walls are those structures, which played a key role in adaptive processes during the evolution of land plants. Cell wall as a structure protecting protoplasts and showing a high structural plasticity was one of the primary subjects to changes, giving plants the new properties and capabilities, which undoubtedly contributed to the evolutionary success of land plants. In this paper, the current state of knowledge about some main components of the cell walls (cellulose, hemicelluloses, pectins and lignins) and their evolutionary alterations, as preadaptive features for the land colonization and the plant taxa diversification, is summarized. Some aspects related to the biosynthesis and modification of the cell wall components, with particular emphasis on the mechanism of transglycosylation, are also discussed. In addition, new surprising discoveries related to the composition of various cell walls, which change how we perceive their evolution, are presented, such as the presence of lignin in red algae or MLG (1→3),(1→4)-β-D-glucan in horsetails. Currently, several new and promising projects, regarding the cell wall, have started, deciphering its structure, composition and metabolism in the evolutionary context. That additional information will allow us to better understand the processes leading to the terrestrialization and the evolution of extant land plants.
EN
Decomposition of litter is a crucial process in terrestrial ecosystems, determining global carbon budget and nutrient turnover. Soil faunas have been shown to accelerate the rates of litter decomposition and nutrient cycling in terrestrial ecosystems. Litter decomposition has recently been observed in winter in alpine/subalpine ecosystems, but the contribution of soil fauna to the decomposition process is not clear. Field experiment using litterbags was conducted in order to quantify the contributions of soil fauna to mass losses of fir (Abies faxoniana) and birch (Betula albosinensis) litters during a freeze-thaw season in three representative alpine/subalpine forests. The litterbags of mesh sizes 0.02 mm, 0.125 mm, 1.0 mm and 3.0 mm were placed on the forest floor in October 2010, and collected after each of the three stages of the freeze-thaw season: OF, the onset of freezing stage (26 October to December 31); DF, the deeply frozen stage (1 January to 4 March 2011); and TS, the thawing stage (5 March to 30 April 2011) over the entire 2010/2011 winter. Over the whole freeze-thaw period, the mass losses of fir litter were 11–12% (0.02 mm), 12–13% (0.125 mm), 14–15% (1.0 mm) and 17–19% (3.0 mm), and that of birch litter were 10–13% (0.02 mm), 12–15% (0.125 mm), 13–18% (1.0 mm) and 17–22% (3.0 mm), respectively, depending on the altitude. The mass losses caused by microfauna, mesofauna and macrofauna for the fir litter accounted for 6–9, 12–13 and 22–25%, respectively and that for the birch litter accounted for 8–11, 13–15 and 25–27%, respectively. Furthermore, the contributions of soil fauna to mass loss showed an increasing trend with increasing body size regardless of species at three stages of the freeze-thaw period. These results suggest that soil fauna contributes strongly to litter decomposition during the freeze-thaw period in alpine/subalpine regions.
EN
The aim of the present research work was to evaluate the influence of lithogenic conditions on the physico-chemical properties, quantity and quality of humus components in the black earths from the Małopolska Upland. Soil samples were collected from 5 soil profiles which represented proper black earth (profiles No. 1-4) and degraded black earth (profile No. 5). All the investigated soils were under sward. The examined black earths were characterised by different physico-chemical properties strongly related to the parent rock type. Their pH level and sorption capability were decreasing with a decrease in the clay content of the soil texture. Humus resources were the lowest in sandy black earths (average 212 t ha-1) and the highest in the black earh derived from clay (454 t ha1). In the humus composition of the examined black earths, humic acids dominated over fulvic acids. In the A horizons, the Ch:Cf ratio was close to 1, and lower in the upper parts of these horizons which is typical of turf soils. Humus horizons in some of the investigated black earths were classified as epipedon anthropoid according to phosphorus content soluble in 1% citric acid (109 P kg-1 soil).
EN
Anthropogenic alterations of the recent millennia of our era, in the loess areas of the Lublin Upland are clearly visible in the composition and character of the sediments that fill river valleys. This paper is an attempt to review this issue on the example of a small river valley that runs through the loess relief regions near Lublin. Samples were taken from deep drilling (up to 6 m) in the three cross-sections of the valley (Ożarów, Jastków, Snopków). A total of 172 samples taken from 5 drillings were investigated. The results obtained allow to conclude that delluvial processes dominated in the course of sediment formation that filled the Ciemięga river valley. Those delluvial processes started in the Neolyth by climatic changes and cutting down forests for the incoming agriculture - and have been intensified since the Middle Ages up till now. It is seen in a clear correlation between the growing part of ash components and mineral interbeddings in the peat deposits, as well as in the presence of cereal grains and weed pollen from cultivated fields in the investigated samples. In the chemical composition of the sediments, anthropogenic enrichment of K, P, Fe, Mn, Pb, Cr, Cu, Zn, and Co is observed.
EN
In the last Vistulian glacial period, the profiles of periglacial perstructions and the profiles of old cryosols were formed in the extra glacial and gradually released from retreating continental glacier regions, originally in conditions of over 6-8 ka existing arctic desert before approximately 14.5 ka, and then from 14.5 to 10.5 ka BP, in the changing short rhythms of glacier deserts, shrub and park tundras as well as in short lasting pine-birch and birch forests. The whole profile thickness of the remaning periglacial horizons of the pleistocene paleosoils at the earth surface consists of a sequence or series of periglacial frost perstruction zones. In the cryogenic perstruction process of surface and subsurface sediment layers in the periglacial environment there were diagnostic horizons - cryosideric - crBv, cryoargillic - crBt, and cryospodic - crBk formed. Their localisation in the perstruction profile, in the soil horizons profile and the grain size profile, with readily recognisable associations of cold climate characteristics, may be used for quantification and diagnosis of rusty and parabrown paleosoils in the framework of superordinatektaxonomic unit of paleocryosols.
EN
An attempt was made to evaluate the response of the ecosystem to changes of climate in ten pine forest stands. It was assumed that the ecosystem response to environmental change can be evaluated by examining differences in ecosystem structures and would be measured through the change in the rates of ecosystem processes. The changes of structures and rates are registered along the longest, N-S transect available on the European Continent above 50°N. This transect is within the belt crossing Northern Scandinavia (Norway and Finland up to 70°N), the Baltic States (Estonia, Latvia, Lithuania) and Eastern Poland (from 50°N). The transect covers 20 degrees of latitude and is more than 2000 km long. The difference in average annual temperature (long-term measurements) between the two extreme sites exceeds 9°C, and there is a regular southward increase of average site temperature. Precipitation does not show any regular pattern of change along the transect. Average site elevation is 86 m a.s.l., and the average forest age 110 years. All sites are dominated by an overstory of Scots pine, and in the Braun-Blanquet classification they all belong to Vaccinio-Piceetea class of forests, which are common in Europe. During four years of study (1997, 1998, 1999 and 2000) four expeditions to the transect were organized. The following studies were conducted on each site: the origin and structure as well as physical and chemical features of soils; tree stand age, height, basal area, biomass and carbon content; vertical and horizontal structure of ground vegetation, its diversity, biomass and carbon content; litter fall, its decomposition and accumulation; and radial growth of trees.
EN
The aim of this study was to analyse the acidity and buffer abilities of selected soils occurring within terrestrial (forest, arable and meadow) ecosystems, under specific form of protection within the Lasy Janowskie Landscape Park. The results of the study indicate that the very acid and acid reaction of the soil environment is the result of natural processes, such as relations between mother rock and plant cover (low pH, high value of hydrolytic and exchangeable acidity, and high content of mobile aluminum), and low degree of saturation of the sorption complex with bases. The greatest buffering abilities showed typic gley soil (Dystric Gleysol), peat soil (Terric Histosol), and accumulation horizons of other soil types.
EN
In Poland, soil cover has been identified in detail in terms of spatial variability which resulted in soil records that comprise data on soil properties put in order according to the criteria of administrative and physiographic division. These data were not available in the numerical format till quite recently which meant that their application did not fully meet present requirements of agriculture, environment and landscape conservation, modification of functions, etc. The newly created numerical soil map at the scale of 1.500 000 corrects this difficulty. The main information content of the map at the scale of 1:500 000 covers complexes of soil usefulness and soil types and subtypes. Basic characteristics such as granulometric composition, origin of the parent rock and land use attributes, i.e.: forest, grassland, arable land, waters or barren land, are also included. Apart from the soil coverage, the map contains 13 topographic coverages.
EN
The distribution of total lithium content with depth was studied in soils of selected forest ecosystems, with regard to their physicochemical properties and possible anthropogenic impact. The six soil profiles, representing forest soils, were selected for the study: Udipsamments formed from sandr sand, eolian sand and alluvial sand, and Haplorthods Humic formed from eolian sand, Dystrochrepts formed from alluvial silt and Eutrochrepts formed from boulder loam. The total Li content was determined after previously dissolving the samples in a mixture of concentrated acids: hydrofluoric and nitric (HF+HNO3). The content of Li in solutions was determined using the FAS method on PU-9100 X Philips spectrometer. The total lithium content in studied soils under investigations occurs in range of 1.63 to 229.68 mg kg-1 and was considerably lower in organic horizons (1.63-8.07 mg kg-1 ) than in mineral (17.58-229.68 mg kg-1). The concentration of lithium in subhorizons of forest litter increases according to the litter decomposition degree (01<0f<0fh). The Li concentrations found in all forest soils formed from sand were much higher than its natural content in surface mineral horizons of arable soils 1.30-56.00 mg kg-1. The total lithium content in studied soils was negative statistically correlated with the content of organic carbon (-0.6062), silt and clay fraction (-0.7131 and -0.6322), hydrolytic acidity (-0.5222), sum of exchangeable bases (-0.6196) and cation exchange capacity (-0.6277).
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