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1
Content available remote The BALTEX/Baltic Earth program : Excursions and returns
EN
The Baltic Sea Experiment (BALTEX) started in 1993 as part of the Global Energy and Water Cycle Experiment (GEWEX). It was later organized into three programs: BALTEX I, BALTEX II, and Baltic Earth. Here, we examine in a brief overview the overall BALTEX achievements, including program goals, risks encountered during the research journey, and knowledge development when finalizing the programs. During three decades of climate and environmental studies of the Baltic Basin within the BALTEX/Baltic Earth programs, significant steps have been taken towards improved scientifically constructed knowledge and efforts to disseminate this knowledge to neighboring sciences and the public. These programs have illustrated the need to actively navigate the European research arena while remaining an independent science network. The well-organized International Baltic Earth Secretariat and many dedicated scientists made the research excursions safe and successful. The learning process relates to improved knowledge of the dynamics of the atmosphere–ocean–land climate system in the Baltic Sea region, the cycling of carbon and other substances, the region's anthropogenic climate and environmental changes, and how global warming and regional human activities can be detected outside natural variability.
EN
The utilization of nitrogen (N) fertilizer in peatlands, with the aim of increasing crop growth and production, is also reported to increase carbon dioxide (CO2) emissions. The application of coal fly ash (CFA) to soil may change soil physico-chemical characteristics, thereby influence carbon mineralization, but its effect on CO2 production is not yet clear. Consequently, the purpose of this study was to quantify the CO2 production of tropical peatlands that received N fertilizer and CFA. In the laboratory experiment, CFA equivalent to the application of 150 Mg•ha−1 in the field was added to peatlands with and without N fertilizer. These mixtures were then incubated at 70% waterfilled pore space (WFPS) for 30 days at room temperature. Carbon mineralization was measured on a 5-day basis, while several chemical characteristics of treated peatlands, including pH, hot water-soluble C, exchangeable-Ca, -Mg, -Fe, and -Al were measured at the conclusion of the incubation period. This study identified that N fertilizer application increased the CO2 production of tropical peatlands from 29.25 g•kg−1 to 37.12 g•kg−1. Furthermore, the application of CFA on tropical peatlands reduced CO2 production of tropical peatlands with and without N fertilizer. Decreasing the amount of hot water-soluble carbon from peatlands may account for the reduced CO2 production of peatlands with CFA. The study also showed that exchangeable-Ca, -Mg, -Fe, and -Al increased in peatlands with CFA application, and these multivalent cations were also attributed to a reduction of CO2 production. In conclusion, the negative effects of N fertilizer application on peatlands in increasing CO2 emission may be reduced by the application of CFA.
EN
The study took as a purpose to determine the Total Carbon (TC) content in the biomass, the Starch Carbon fraction (SC) and its annual dynamics in the biomass of perennial organs (stem and root) in adult trees of two of walnut tree (Carya illinoinensis). Four adult Western and Wichita tree stem and root samples were carried out monthly for a whole year. The TC was determined with an elemental analyser and the SC has gotten based on the molecular mass of the glucose (0.40 gC/gGlucose). t-Student test was performed between varieties per organ for the comparison of TC and SC through the program SPSS 15.0 with a significance of p ≤ 0.05. The results in Western variety were 160.02 kg TC and 4.90 kg SC to 7.54 kg SC in the stem; 64.58 kg TC and 1.74 kg SC to 3.09 kg SC in the root; in Wichita variety were presented 119.72 kg TC and 4.49 kg SC to 6.83 kg SC in the stem; 45.72 kg TC and 1.35 kg SC to 2.75 kg SC in the root. The root was the organ where the greatest amount of SC was stored in relation to the stem, due this latter constitutes a transport organ. Temperature has a marked inversely proportional influence on the accumulation of SC in both varieties. Global solar radiation and solar radiation proportionally influence the accumulation of SC.
EN
Due to natural mechanisms of transformation the carbon compounds contained in the atmosphere into the humus, soil is an important factor controlling the concentration of atmospheric CO2. The mass of carbon contained in organic matter accumulated in the surface layer of the Earth’s crust is greater than the mass of this element in the atmosphere or biomass of all the organisms living over the globe. Over the recent years, much attention has been paid to the role of soils in limiting the reasons of climate changes, considering the possibility of increasing carbon sequestration in this matrix. This way of approaching the problem of the greenhouse effect, which does not require an involvement of complex and expensive technological solutions aimed at capturing and storing the atmospheric CO2, and additionally contributing to improving the quality of soil and water environment, and soil productivity is fully sustainable and combines the environmental, economic and social issues.
PL
Dzięki istnieniu naturalnych mechanizmów transformacji związków węgla zawartych w atmosferze w związki próchniczne, gleba stanowi istotny czynnik kontrolujący stężenie atmosferycznego CO2. Masa węgla zawartego w materii organicznej nagromadzonej w powierzchniowej warstwie skorupy ziemskiej jest większa niż masa tego pierwiastka w atmosferze lub biomasie organizmów żywych. W ostatnich latach wiele uwagi poświęca się roli gleb w ograniczeniu przyczyn zmian klimatycznych, poddając pod rozwagę możliwości zwiększenia w nich sekwestracji węgla. Taki sposób podejścia do problemu efektu cieplarnianego, nie wymagający wprowadzania złożonych i drogich rozwiązań technologicznych nakierowanych na wychwytywanie i magazynowanie atmosferycznego CO2, a dodatkowo przyczyniający się do poprawy jakości środowiska gruntowo-wodnego oraz produktywności gleb jest w pełni zrównoważony, gdyż łączy ze sobą zarówno kwestie środowiskowe, gospodarcze i społeczne.
EN
The regional carbon budget of the climatic transition zone may be very sensitive to climate change and increasing atmospheric CO2 concentrations. This study simulated the carbon cycles under these changes using process-based ecosystem models. The Integrated Biosphere Simulator (IBIS), a Dynamic Global Vegetation Model (DGVM), was used to evaluate the impacts of climate change and CO2 fertilization on net primary production (NPP), net ecosystem production (NEP), and the vegetation structure of terrestrial ecosystems in Zhejiang province (area 101,800 km2, mainly covered by subtropical evergreen forest and warm-temperate evergreen broadleaf forest) which is located in the subtropical climate area of China. Two general circulation models (HADCM3 and CGCM3) representing four IPCC climate change scenarios (HC3AA, HC3GG, CGCM-sresa2, and CGCM-sresb1) were used as climate inputs for IBIS. Results show that simulated historical biomass and NPP are consistent with field and other modelled data, which makes the analysis of future carbon budget reliable. The results indicate that NPP over the entire Zhejiang province was about 55 Mt C yr[^-1] during the last half of the 21st century. An NPP increase of about 24 Mt C by the end of the 21st century was estimated with the combined effects of increasing CO2 and climate change. A slight NPP increase of about 5 Mt C was estimated under the climate change alone scenario. Forests in Zhejiang are currently acting as a carbon sink with an average NEP of about 2.5 Mt C yr[^-1]. NEP will increase to about 5 Mt C yr[^-1] by the end of the 21st century with the increasing atmospheric CO2concentration and climate change. However, climate change alone will reduce the forest carbon sequestration of Zhejiang.s forests. Future climate warming will substantially change the vegetation cover types; warm-temperate evergreen broadleaf forest will be gradually substituted by subtropical evergreen forest. An increasing CO2 concentration willhave little contribution to vegetation changes. Simulated NPP shows geographic patterns consistent with temperature to a certain extent, and precipitation is not the limiting factor for forest NPP in the subtropical climate conditions. There is no close relationship between the spatial pattern of NEP and climate condition.
PL
Szybko zwiększające się zużycie zasobów Ziemi stanowi realne zagrożenie ich bliskiego wyczerpania. Oznacza to, że jeśli nie nastąpi jakiś przełom w nauce, zagrożona jest możliwość realizacji idei zrównoważonego rozwoju mówiącej: "postępuj tak, aby zapewniając możliwość zaspokajania potrzeb obecnych pokoleń, nie zagrażać zdolności przyszłych pokoleń do zaspokajania ich własnych potrzeb". Wyczerpaniu zasobów towarzyszy zanieczyszczanie geoekosystemów Ziemi poprzez wydalenie do nich związków chemicznych w trakcie wydobywana, przerobu i użytkowania tych zasobów przez cywilizację ludzką. Przyroda wykształciła mechanizmy eliminacji szkodliwego oddziaływania większości związków chemicznych występujących w przyrodzie, to jednak człowiek poprzez swoją działalność cywilizacyjną wielokrotnie zwiększa ilość tych związków emitowanych do geoekosystemów, przekraczając naturalne zdolności do samooczyszczania. Jednak rozwój techniki i technologii, w szczególności inżynierii środowiska, umożliwia eliminacje zagrożeń pochodzących od zanieczyszczeń poprzez intensyfikację naturalnych procesów samooczyszczania będących integralną częścią naturalnych cykli węgla, azotu i tlenu. Wprowadzone są także nowe, nieznane w przyrodzie procesy, które umożliwiają neutralizacje negatywnego wpływu zanieczyszczeń na geoekosystemy. Można więc powiedzieć, że z technicznego punktu widzenia możliwe jest utrzymanie geoekosystemów w stanie zapewniającym pełną możliwość korzystania z nich przez przyszłe pokolenia. Problem jednak w tym, że z uwagi na wysokie koszty, a także brak woli, degradacja geoekosystemów ciągle postępuje, zbliżając się na niektórych obszarach do stanu nieodwracalnej dewastacji. Tak więc człowiek dysponuje odpowiednimi mocami technicznymi pozwalającymi na zachowanie zrównoważoności środowiska, nie czyni tego jednak - i to na wielu obszarach - głównie z braku woli skierowania odpowiednich środków materialnych. Kwestią otwartą pozostaje w jaki sposób kształtować postawy, wspomagane przez nakazy wynikające z uregulowań prawnych, zapewniając realizację zrównoważoności w zakresie środowiska naturalnego.
EN
The rapidly increasing consumption of the Earth's resources carries with it the threat of these being exhausted over the shorter or longer terms. What this means is that, if no major breakthrough in science takes place, a threat will also be posed to sustainable development itself, inasmuch as that this entails such a means of proceeding with development as "meets the needs of the present without compromising the ability of the future to meet its own needs". The tendency for resources to run out goes hand in hand with the pollution of the world's geoecosystems through the release into them of chemical compounds - as the said resources are being extracted, processed or utilised by human civilisation. Nature has come up with mechanisms by which the majority of chemical compounds present in it can be neutralised, but human activity has gone far beyond natural systems' capacity for self-purification, in terms of the sheer amounts of chemical compounds emitted. Equally, the development of techniques and technologies - in environmental engineering in particular - is capable of eliminating most threats associated with the pollutants already released into the environment, the trick being to derive intensified versions of the various means of natural selfpurification inherent in the processes by which carbon, nitrogen and oxygen in particular are cycled within geoecosystems. It has further proved possible to introduce new processes unknown in nature whereby the negative impacts of pollution on geoecosystems can be neutralised. In consequence, it is reasonable to suggest that we possess the technology to allow geoecosystems to be maintained in a state that does indeed allow future generations undiminished possibilities for making use of them. The problem here is that, thanks to the high costs involved - and (in part in consequence of that) a perceptible lack of will to act, there is ongoing degradation of geoecosystems - so ongoing in fact that an "irreversible" state of degradation may be being approached in certain areas. Thus, while humankind may be in possession of the appropriate technical and technological power allowing for environmental sustainability to be achieved, this aim is not being pursued in many areas on account of an absence of the will to target the necessary material resources at the problem. A question that therefore remains open concerns the ways in which we might shape attitudes (also as necessary using the force of law to order the carrying out of certain tasks) in such a way that sustainability as regards the natural environment is achieved.
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