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[en] Reducing emissions from deforestation and forest degradation, and enhancing carbon stocks (REDD+) is a crucial component of global climate change mitigation. Remote sensing can provide continuous and spatially explicit above-ground biomass (AGB) estimates, which can be valuable for the quantification of carbon stocks and emission factors (EFs). Unfortunately, there is little information on the fate of the land following tropical deforestation and of the associated carbon stock. This study quantified post-deforestation land use across the tropics for the period 1990–2000. This dataset was then combined with a pan-tropical AGB map at 30 m resolution to refine EFs from forest conversion by matching deforestation areas with their carbon stock before and after clearing and to assess spatial dynamics of EFs by follow-up land use. In Latin America, pasture was the most common follow-up land use (72%), with large-scale cropland (11%) a distant second. In Africa deforestation was often followed by small-scale cropping (61%) with a smaller role for pasture (15%). In Asia, small-scale cropland was the dominant agricultural follow-up land use (35%), closely followed by tree crops (28%). Deforestation often occurred in forests with lower than average carbon stocks. EFs showed high spatial variation within eco-zones and countries. While our EFs are only representative for the studied time period, our results show that EFs are mainly determined by the initial forest carbon stock. The estimates of the fraction of carbon lost were less dependent on initial forest biomass, which offers opportunities for REDD+ countries to use these fractions in combination with recent good quality national forest biomass maps or inventory data to quantify emissions from specific forest conversions. Our study highlights that the co-location of data on forest loss, biomass and fate of the land provides more insight into the spatial dynamics of land-use change and can help in attributing carbon emissions to human activities. (letter)
[en] The concepts of the cities we know nowadays, and which we are accustomed to, change at a very rapid pace. The philosophy of their design is also changing. It will base on new standards, entering a completely different, futuristic dimension. This stage is related to changes in the perception of space, location and lack of belonging to definite, national or cultural structures. Cities of the future are cities primarily intelligent, zero-energetic, zero-waste, environmentally sustainable, self-sufficient in terms of both organic food production and symbiosis between the environment and industry. New cities will be able to have new organisational structures—either city states, or, apolitical, jigsaw-like structures that can change their position—like in the case of the city of Artisanopolis, designed as a floating city, close to the land, reminiscent of the legendary Atlantis. This paper is focused on the main issues connected with problems of the contemporary city planning. The purpose of the research was to identify existing technological solutions, whose aim is to use solar energy and urban greenery. The studies were based on literature related to future city development issues and futuristic projects of the architects and city planners. In the paper, the following issues have been verified: futuristic cities and districts, and original bionic buildings, both residential and industrial. The results of the analysis have been presented in a tabular form.
[en] The utilization of agricultural residues may become one of the major sources for production of energy from biomass. The objective of this paper was to analyse the type and quantity of agricultural residues and to determine their energy potential. Area of study: The Međimurje County (north Croatia).The paper analyses three models of sustainable agricultural residues management applying the multi-criteria analysis. The assessment included potentially available quantities of residues in crops, fruit, viniculture and livestock production. For determining the most appropriate model of residues utilisation the multi-criteria analysis was applied.The results show that total quantities of agricultural biomass amount to 323,912 t with energy potential of 1,092 TJ annually. The largest sustainably available potential of agricultural biomass consists of biomass from arable crops production, with total quantity of 33,670 t followed by 281,233 t of manure from livestock production. The lowest share of potential biomass are pruning residues in fruit and grapevine production with total available residual quantity of 8,109 t. Also, it results from the multi-criteria analysis that a central large scale plant for biogas production is the most feasible facility for such production. The results of this paper provide ground for further development of the models for assessing the sustainability of using agricultural residues, and they can also serve as a basis for assessments of bioenergy projects in specific regions of the European Union.
[en] Tropical forests ecosystems remain the most diverse on the planet, and store considerable amounts of biomass and carbon. Despite the importance of tropical forests, sizable knowledge gaps exist regarding species diversity, plant biomass and carbon. These knowledge gaps are particularly large in tropical systems, and even more so in the African tropics. This study provides baseline data on species composition and vegetation structure, and evaluate variation along elevational gradient transecting of four elevation-forest types: lowland, mid-elevation, sub-montane and montane forest in the Rumpi Hills Forest Reserve of Cameroon. We collected data on tree species diversity, above-ground biomass and carbon in 25 1-ha plots sampled in 500 m long x 20 m width transect. Results revealed high species diversity, particularly in lowland forest. Overall, the study enumerated 12,037 individuals (trees ≥ 10 cm dbh) of 441 species. The mean species per plot decreased with increasing elevation, 112 in lowland, 81 in mid-elevation, 60 in submontane and 38 in montane forest. Above-ground carbon averaged 162.88±50 t ha-1. We found the greatest carbon storage and tree and liana species diversity at low elevations. Our results indicate that high species diversity and occurrence of larger tree species are more important in carbon storage in lowland forest than at higher elevations. These findings are useful for management and land use planning of the forests in the Rumpi Hills Forest Reserve. (author)
[en] Agarwood is the resinous product of several tree species of family Thymelaeaceae such as Aquilaria spp. Unsustainable harvesting has threatened the existence of agarwood producing species in their natural habitat. Therefore, the present study was developed to facilitate an effective and efficient method to produce Aquilaria malaccensis seedlings by In vitro culture. Here, we optimized the aeration rate in the bubble column reactor and the immersion time on the temporary immersion system (TIS)-RITA® bioreactor and compare the growth rate of A. malaccensis with both systems. A. malaccensis shoot cultures were propagated in Murashige and Skoog (MS) semisolid medium and then pre-conditioned in thin layer culture before bioreactor cultivation. A. malaccensis shoots in the bubble column reactor were subjected to variable aeration rates of 0.05 and 0.1 vvm, while the immersion variation within the TIS-RITA® bioreactor was 5 and 15 min for every 4 h. The results showed that 15 min immersion for every 4 h increased the number of A. malaccensis shoot regeneration. Nonetheless, no significance difference was observed on biomass acquisition in both bubble column bioreactor and TIS-RITA® bioreactor. Therefore, our findings indicate that immersion period was more critical than aeration rate for A. malaccensis shoot cultivation. (author)
[en] Three weeds, Enhydra flactuans, Amaranthus viridis and Chenopodium album were considered as Cd accumulating plants. Accumulated Cd in C. album reached to 0.32 mg for each plant under soil Cd stress of 15 mg. Thus, Cd accumulation capability of weeds was decreased with the increased using rate of Cd and it was between 1.64% and 4.96%. After 45 days? of Cd stress, the redistribution of Cd content in the root and shoot was studied from underground parts to above ground parts. The outcome confirmed that weed species had sophisticated acceptance to Cd and could accumulate affectively. They did not show any abnormal growth appearance even in soils having 15 mg kg−1 Cd, and for C. album, the Cd content in the roots was up to 264.32 mg kg−1 dry biomass while in the shoots it was about 126.55 mg kg−1. This signified that three weeds behaved as decent accumulating plant although they showed infirm ability in transporting Cd from below ground biomass to above ground biomass. Afterwards, shoot:soil and root:soil further proved that, studied weed species were likely to uptake more Cd as a way of diminution of the mobility of Cd. So, this research predicts that using green technology as a process of phyto-mitigation of trace elements from the defiled soils would be a good choice. (author)
[en] To provide a basis for the reasonable utilization and protection of natural Prunella vulgaris L. resources, the current study was conducted to analyze the characteristics of reproductive allocation between sexual and asexual reproduction in P. vulgaris populations from heterogeneous environments. Multiple comparison and correlation analyses were carried out to understand the proportions of sexual and asexual reproduction of P. vulgaris in heterogeneous environments. The results showed that total biomass reached its maximum in the ripening period in heterogeneous environments. Each mode of biomass allocation among the different populations was sharp; the biomass allocation to spica and cloning changed dramatically, showing gradient differences with environment changes. The volume-weight, organic matter, water content and species diversity in heterogeneous environments played very important roles in the clonal growth process of P. vulgaris. The intensity of P. vulgaris reproductive allocation was different in different heterogeneous environments, which supports a trade-off relationship between sexual and asexual reproduction. (author)
[en] Plant responses to abiotic stresses such as drought, salt, and heat, have been studied separately, but in fact, plants are exposed simultaneously to a combination of stresses. Therefore, the objective of this study was to explore the morpho-physiological responses of the guar plant to the combination of heat, drought, and salinity with respect to that to an individual stress. Five treatments including heat, drought, salinity, a combination of multiple stresses and control were applied to two guar accessions namely “BWP-5595” and “24320”. The results showed that heat stress enhanced biomass, plant height, leaf number, leaf elongation, and prolonged time to flowering. However, it reduced root length and water use efficiency, but it had moderately negative effect on leaf area, stomatal conductance and number of pods. Contrastingly, drought stress improved root length, water use efficiency, and leaf elongation. It affected negatively leaf area, plant height, and prolonged days to flowering. Drought stress moderately reduced leaf number, biomass, stomatal conductance, and number of pods. Comparatively, salinity stress had a moderately negative impact on all studied traits except leaf number, which was reduced significantly. However, the combination of multiple stresses severely affected all studied traits except water use efficiency. These results show that the adverse effects of the combination of all three stresses were more pronounced than those of either of the individual stresses. Of the two guar accessions used, BWP 5595 showed better performance than accession 24320 in most of the traits measured. This indicates that the effect of multiple stresses differs among the accessions of a species. (author)
[en] Energy is only a utility, it should not lead to feelings or dreams; it is only a question of choosing the most efficient means of heating, cooking, moving, machining, etc., while preserving a pleasant environment. Whether by one means or another, this in itself is of no importance to the citizen. However, if we look at statements and positions, this rationality is often absent; orders of magnitude, availability in space and time, are often forgotten. We move from the pilot experiment to the upheaval of society, forgetting the stages that can be dead ends. We confuse objectives and means by getting enthusiastic about attractive but unrealistic ideas
[fr]L'energie n'est qu'une utilite, elle ne devrait entrainer ni sentiment ni reve; il s'agit seulement de choisir les moyens les plus efficaces pour se chauffer, cuisiner, se deplacer, usiner, etc., tout en preservant un environnement agreable. Que ce soit par une voie ou par une autre, cela n'a pas d'importance en soi pour le citoyen. Pourtant, si l'on regarde les declarations et prises de position, cette rationalite est souvent absente; les ordres de grandeur, les disponibilites dans l'espace et dans le temps, sont souvent oublies. On passe de l'experience pilote au bouleversement de la societe en oubliant les etapes qui peuvent etre des impasses. On confond objectifs et moyens en s'enthousiasmant sur des idees seduisantes mais irrealistes
[en] Ongoing climate change affects complex and long-lived infrastructures like electricity systems. Particularly for decarbonized electricity systems based on variable renewable energies, there is a variety of impact mechanisms working differently in size and direction. Main impacts for Europe include changes in wind and solar resources, hydro power, cooling water availability for thermoelectric generation and electricity demand. Hence, it is not only important to understand the total effects, i.e., how much welfare may be gained when accounting for climate change impacts in all dimensions, but also to disentangle various effects in terms of their marginal contribution to the potential welfare loss. This paper applies a two-stage modeling framework to assess RCP8.5 climate change impacts on the European electricity system. Thereby, the performance of two electricity system design strategies - one based on no anticipation of climate change and one anticipating impacts of climate change - is studied under a variety of climate change impacts. Impacts on wind and solar resources are found to cause the largest system effects in 2100. Combined climate change impacts increase system costs of a system designed without climate change anticipation due to increased fuel and carbon permit costs. Applying a system design strategy with climate change anticipation increases the cost-optimal share of variable renewable energy based on additional wind offshore capacity in 2100, at a reduction in nuclear, wind onshore and solar PV capacity. Compared to a no anticipation strategy, total system costs are reduced.