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DECISION-MAKING PROCESS AND SOCIO-ECONOMIC DYNAMICS OF AGRICULTURAL ACTORS THE CASE OF A METHANISATION UNIT IN THE NORTH OF FRANCE Texto completo
2024
Rakotovao, Miravo | Godard, Lucile | Sauvée, Loïc
Currently, the agricultural sector is facing new challenges. In addition to meeting the population's food needs in sufficient quantity and quality, it must fulfill new energy and environmental functions as well as other non-food uses such as biomaterials and biomolecules. At the regional scale, there is an increase of non-food valorization projects of biomass, including the methanisation plants. In France, the methanisation sector is in full swing with a national target of 1,000 plants by 2020, as defined in the Energy Methanisation Nitrogen Energy plan (EMAA). The development of methanisation sector generates a regional dynamic involving different stakeholders and linking various business sectors. Then the regional methanisation becomes a collective process in which farmers, industrialists, waste managers and local communities are engaged. The objective of this communication consists on understanding the socio-economic conditions in which this kind of regional projects have emerged. For this purpose, the “Centrale de Biométhane du Vermandois”, a regional methanisation plant in the north of France was studied. This analysis contributes to identify the nature of the expectations of the actors engaged, to better understand the governance in place and the decision-making processes surrounding the project. The results show the success factors but also the difficulties of implementation and development of the project. The results also highlight the main motivations of farmers to join the biogas project.
Mostrar más [+] Menos [-]VERIFICATION OF APPLICABILITY OF FOREST GROWTH MODEL AGM IN ELABORATION OF FORESTRY PROJECTIONS FOR NATIONAL FOREST REFERENCE LEVEL Texto completo
2024
Lazdiņš, Andis | Šņepsts, Guntars | Petaja, Guna | Kārkliņa, Ilze
Latvia's forest reference level (FRL) should take in account the future impact of dynamic age-related forest characteristics in order to avoid unduly constraining the forest management intensity as a core element of sustainable forest management practice, with the aim of maintaining or strengthening long-term carbon sinks. The basic for calculations of GHG projections is AGM (Forest growth model) and EPIM (Emissions Projections and Inventory Model). The scope of the study is to verify applicability of the AGM model in elaboration of the forestry projections for elaboration of the FRL according to regulation (EU) 2018/841.
Mostrar más [+] Menos [-]JERUSALEM ARTICHOKE (HELIANTHUS TUBEROSUS L.) AS ENERGY RAW MATERIAL Texto completo
2024
Sawicka, Barbara | Skiba, Dominika | Skiba, Dominika | Kiełtyka-Dadasiewicz, Anna | Danilčenko, Honorata
Jerusalem artichoke is suitable for use in biorefineries due to the very high biomass production and low soil, climate and cultivation requirements. Tubers of this species can be used for the production of methane fermentation or bioethanol. The aboveground part can be used for the production of biomethane, as well as in the direct combustion process or for the production of briquettes and pellets. Of the cultivars tested, Albik and Violet de Rennes proved to be the most useful for energy purposes. An important advantage of Jerusalem artichoke is its resistance to adverse climatic conditions (drought, frost), resistance to diseases and pests and the possibility of self-renewal.
Mostrar más [+] Menos [-]DETERMINATION OF THE RATIONAL PROFILE FOR THE DISK WORKING TOOL WHEN CULTIVATING OF SOD PODZOLIC SOILS Texto completo
2024
Zabrodskyi , Pavlo | Kukharets , Savelii | Zabrodskyi, Andrii | Čėsna, Jonas
Maintaining soil fertility is one of the main objectives of agricultural production. An important factor in soil fertility is its optimal structure. For the minimum cultivation of soil widely used equipped with spherical cut-off discs heavy harrows. The purpose of their use, along with others, in the cultivation of heavy soils, for example, chernozems, is the depression of soil boulders and, thus, the optimal structure. In the conditions of intensification of agricultural production under the influence of such soil-working tools in the cultivation of malocontuitive sod-podzolic soils and running gears of mobile equipment, the destruction of the soil structure, the reduction of the number of agronomically valuable water-supply units, and the spread of soil. Thus, for the cultivation of such soils, it is necessary to use discs of another profile, which would ensure the minimum destruction of agronomically valuable watertight aggregates. In order to create such a working body, the process of structuring the agronomically valuable water-conserving aggregates, factors influencing it and analyzing the energy criteria for the formation of a water-tight structure is considered. The features, which arise during mechanical cultivation of soil, influence of cultivation on its structure and features of the stress-strain state of soil are studied. A mathematical model is developed that allows calculating the stress state of the soil and designing the most rational form of disk working bodies. In the conducted studies, the influence of the depth of cultivation, the number of cutouts, the size of the cutout angle and the length of the chord of the projection were studied. On the basis of the developed mathematical model, a rational profile of the disk working organ for the cultivation of small-coupling sod-podzolic soils was obtained and its tests were performed, which showed a decrease of the erosion-dangerous particles of the soil by (<0,25 mm) 24%.
Mostrar más [+] Menos [-]COMPARISON OF COSTS IN PRE-COMMERCIAL THINNING USING MEDIUM-SIZED AND SMALL-SIZED HARVESTERS Texto completo
2024
Kalēja, Santa | Zimelis, Agris
The aim of this study is to compare productivity and costs of medium-sized and small-sized harvesters in pre-commercial thinning. In this study the data on harvesting productivity were obtained in stands, where biofuel was prepared using two medium-sized and two small-sized harvesters equipped with different harvester heads. In total 677 m3 of wood was prepared with medium-sized harvester, but with small-sized harvesters 1 164 m3 of wood was prepared. Although the total annual costs of small-class harvesters are lower by 16 %, comparing with middle-class harvesters, the productivity rates shown by the middle-class harvester John Deere 1070 E (equipped with H 754 harvester head) are significantly higher and the average wood preparation costs are lower, comparing with the other harvesters employed.
Mostrar más [+] Menos [-]EDUCATION AS BASIS OF SUSTAINABLE DEVELOPMENT Texto completo
2024
Feher, Andrea | Adamov, Tabita | Orboi, Manuela Dora | Raicov, Miroslav | Băneș, Adrian
The main objective of the article is to present the level of education in some selected countries, and to explain how education determines a sustainable growth. Education is the main factor to achieve both economic and employment growth. At the same time, education plays an important role for a sustainable improvement of the standard of living in the world. Supporting education is also one of the aims of the 2030 Agenda for Sustainable Development (Goal 4), but education appears in a number of other SDG targets too. The countries that allocate the most capital for education are Norway, Denmark, Sweden, United Kingdom, Belgium, Finland (over 6.7% of GDP). The share of GDP allocated for education in Romania is only 2.7. This directly affects both the physical conditions for carrying out educational and research activities in school units and the qualitative level of the educational act. The Pearson correlation coefficient (r) between the real GDP/capita (VAR01) and share of GDP for education (VAR02) for our study is 0.694, which again underlines the close correlation between the allocation of funds for education and research and the level of development from a country. The Pearson correlation coefficient (r) between supporting education from GDP and top 100 universities is relatively low (r = 0.287), reflecting an insufficient correlation between the two variables. As a result, the education system in a country must be adjusted and supported both financially and through the adoption of viable policy decisions that will ensure increased performance in the educational system.
Mostrar más [+] Menos [-]METHOD FOR SHALLOW DRAINAGE DITCH NETWORK GENERATION USING REMOTE SENSING DATA Texto completo
2024
Melniks, Raitis | Ivanovs, Janis | Lazdins, Andis
Aim of this study is to develop a method for automatic shallow drainage ditch generation to drain terrain depressions using four factor least cost surface which is obtained using LiDAR (light detection and ranging) data and Sentinel-2 multispectral satellite imagery. LiDAR data are used for depression mapping in DEM, flow accumulation and slope modelling as well as CHM (canopy height model) to obtain relative vegetation height. Sentinel-2 imagery was used for land cover type identification as well as separating coniferous and deciduous forest stands. Study area is located in western Latvia and is 25 km2 large. Least cost surface connects DEM depressions and already existing drainage ditches by best possible path for shallow ditch network digging. Different methods are applied to determine depressions which can be drained as well as changes of affected drained area and depression depth. This results in suitable areas where to create shallow ditches to improve water runoff. Results show that using this method average reduction of area of depressions is 79% and average length of shallow ditches on each drained depression hectare is 370 m.
Mostrar más [+] Menos [-]CHARACTERIZATION OF MICROALGAE-BASED FEED SUPPLEMENT AND THEIR POSSIBLE INFLUENCE ON CATTLE RUMEN MICROBIAL ECOSYSTEM Texto completo
2024
Malyugina, Svetlana | Černohous, Milena | Látal, Oldřich
Rumen is a complex ecosystem where feed consumed by animals is digested by the help of rumen protozoa. They plays an important role in contributing nutrients to the host animal. This study aimed to investigate the effects of dietary inclusion of unicellular microalgae Chlorella vulgaris spp. on total count and generic composition of protozoa in cows rumen. In this study, dietary treatments were tested during three 21-d experimental periods. Each of period content different amount of microalgae supplement. In the first experimental period in cows feed was added 30g (3,14g/kg of DM) of Chlorella, in second period-90g (9,6g/kg of DM) of Chlorella and in third period-170g (18,7 g/kg of DM). As a result of this study, ciliates of 10 genera were detected and identified. The number of this genera and total amount of ciliates were counted. The analysis of rumen protozoa population in tested cows shows visible effect of the presence of microalgae in cows dietary. In particular, the density of ciliates protozoa of the cows treated with 90 and 170 g of algal supplement was visibly higher compare to results from the control diet. Microalgae-based supplement diet had stimulative effect on ruminal protozoa population and caused increasing of many protozoa genera such as Isotricha, Dasytricha, Charonina, Buetschlia, Ostracodinium, Ophryoscolex.
Mostrar más [+] Menos [-]SUSTAINABLE, CIRCULAR AND INNOVATIVE VALUE CHAINS USING GROWING SUBSTRATA ALTERNATIVE TO PEAT FOR THE CULTIVATION OF NUTRACEUTICAL SPECIES Texto completo
2024
Greco, Carlo | Comparetti, Antonio | Mammano , Michele Massimo | Orlando, Santo
The modern agricultural system is wasteful, with Europe generating some 700 million tonnes of agricultural and food waste each year. In the context of the agri-food chain, the ‘circular economy’ aims to reduce waste while also making best use of the ‘wastes’ produced by using economically viable processes and procedures to increase their value. In this paper we will try to frame the key issues associated with food waste into the emerging bioeconomy and circular-economic mode, suggesting that these three concepts are intertwined, and considering them unitarily might provide win-win solutions that minimize wastage, promote income growth and job creation, and prompt sustainable local development. In terms of performance and economic considerations, peat is in many ways an ideal constituent of soilless growing media. Peat has become the material of choice throughout plant production systems from propagation to saleable ‘finished plant’ material. However, the extraction of peat has well documented negative impacts on the environment; arguably the most important of these is the release of stable, sequestered carbon into the active carbon cycle, thereby exacerbating climate change. During the last 20 years, peat extraction has come under increasing scrutiny throughout Europe and particularly in the UK. This has generated an abundance of studies examining a diverse range of alternative materials (as compost, vermicompost, digestate, biochar). In the selection of new materials, environmental considerations have become as important as performance and economic cost. In this context there has been a justifiable emphasis on organic materials derived from agricultural, industrial and municipal waste streams. For future urban sustainability it is necessary to develop integrated processes, which can be part of a circular bio-economy. However the challenge still remains of simultaneously recycling the nutrients from the waste. The greenhouse horticulture applied to nutraceutical species is the ideal sector for improving the conversion rate of organic waste into food and health friendly products. On farm composting/vermicomposting/pyrolysis/anaerobic digestion and the use of the end-product to the partial substitution of peat in nursery activity allows reducing the environmental and economic costs in the production of potted plants.
Mostrar más [+] Menos [-]CUT-AWAY PEATLAND RE-CULTIVATION WITH FAST GROWING WOODY PLANTATIONS: COST-BENEFIT ANALYSIS. Texto completo
2024
Makovskis, Kristaps | Lazdina, Dagnija | Popluga, Dina
In Latvia peat production is historically important economic sector, giving significant contribution to rural economic development and providing work places in rural areas, where other job opportunities are limited. Every peat extraction field has certain lifespan, based on economic, social or ecological assumptions. Every peat field could be extracted for set period of time, after which peat extraction is not feasible any more. Current legislation in Latvia requires re-cultivating of places, where mineral resources, including peat, were extracted. Aim of the study is to evaluate afforestation as one of the cut-away peatland re-cultivation possibility. Economic analysis were done for extracted peat field afforestation with birch, black alder, grey alder, pine, spruce, hybrid aspen, poplar and willow. The economic calculations were done comparing different timber products from plantations, different planting materials and plantation lifespans. Lowest investment costs for plantation establishment on cut-away peatlands are for pine and spruce plantations and highest for willow plantations. Highest revenues in plantations with 20 years rotation cycle are in poplar plantations with 0.2 m cuttings and lowest in grey alder plantations. In plantations with rotation cycle 40 years highest revenues are in hybrid aspen plantations and lowest in pine plantations.
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