Agriculture practices have an important role to play in mitigating climate change due to atmospheric enrichment of carbon dioxide, and other greenhouse gases (GHG). Land management can strongly influence soil carbon stocks and careful management can be used to sequestered soil carbon. It is important to propose contemporary management practises to farming, like the conversion from a tillage system to no-tillage, incorporation of cover crops and forages in the crop rotation, use of crop residues and biosolids e.g. mulch, implementation of biocrops, as well as integrated nutrient management which including compost/manures as well as the precision use of fertilizers and integrated pestmanagement. Sustainable management in agriculture should reduce and avoid theintroduction of carbon dioxide (CO2) to the atmosphere, which is one of three most
prevalent GHGs directly emitted by human activity. CO2 is the most importantanthropogenic GHG, and according to IPCC Fourth Assessment Report (2007), anthropogenic CO2 emissions grew by about 80% between 1970 and 2004. Carbon sequestration is a process through which agricultural and forestry practices remove carbon dioxide (CO2) from the atmosphere into a form that does not affect atmospheric chemistry (Lal, 2004a). A natural way to trap atmospheric CO2 is by photosynthesis, where carbon dioxide is absorbed by plants and turned into carbon compounds, stored or fixed C as soil organic carbon (SOC). The SOC pool consist litter, humads and humus, which it is comprised of mixtures of plant and animal residues at various stages of decomposition along with microbial by-products (Lal, 2004a). Agriculture is responsible for 13.5% of global anthropogenic GHG emissions (IPCC, 2007), but if sustainable land management practices are implemented, agricultural soils could become a carbon sink (Dumanski et al., 1998). There are five principal global carbon pools. The oceanic pool (38 Gt) is the largest, followed by the geologic (5 Gt), pedologic (2.5 Gt), biotic (0.56 Gt), and the atmospheric pool (0.76 Gt). The soils beneath the oceans are the most important reservoir of carbon in the terrestrial biosphere and contain three times the amount as compared with those that are found in vegetation (Lal, 2004b; SEC, 2009). Soils contain more than twice the carbon that can be found in the atmosphere and the loss of carbon from soils can have a significant effect on atmospheric CO2 concentrations, which can influence the climate (Smith, 2008). Many studies have examined the sequestration potential in agriculture and forestry in Europe (Smith et al., 1997; Smith et al., 2000; Vleeshouwers & Verhagen, 2002; Freibauer et al., 2004; Smith, 2004;) and globally (Smith 2004; IPCC 2007; Lal, 2004a), as well as in other regions of the world such as North America (Dumanski et al., 1998; Franzluebbers & Follett, 2005) or Africa (Ringius, 2002). The potential for carbon sequestration in the European Union (EU) is approximately 90–120 Mt C/y, in the US cropland is 75–208 Mt C/y, in Canada is approximately 24 Mt C/y, to obtain this potential, optimal land management practices have to be implemented (Hutchinson et al., 2007). It is estimated that the global potential scale of carbon sequestration in soils used for agricultural purposes is around 0.3 t C/ha/y on arable lands, and around 0.5 – 0.7 t C/ha/y on grasslands (IPCC, 2000). The conducted researches indicate existence of a high potential for carbon sequestration in soils under agricultural crops. Depending on the used method for its evaluation and it range between from 0.15-0.22 t C/ha/y for willow (Bradley & King, 2004) up to 0.93 t C/ha/y for Miscanthus (Matthews & Grogan 2001). The net soil carbon sequestration simulated for biocrops in Poland was around 0.38 – 0.95 t C/ha/y Miscanthus crops and 0.22 – 0.39 t C/ha/y for wllow coppice (Borzecka-Walker et al., 2008). There are many policies, directives, standards, as well as norms in the EU designed to stimulate and support the reduction of GHG emission and to improve the carbon mitigation potential. The publication of a Green paper “Towards a European strategy for the security of energy supply” (2000) started a debate on energy security, which is considered a key element of politico-economic independence of the EU. It stressed the need to improve the organisation's strategic stocks of raw materials and coordinate its use. Additionally, the European Commission presented a White Paper that sets out the actions necessary to strengthen the Union's ability to adapt to a changing climate. To support the biofuels industry, the Energy Taxation Directive allows exemptions or reductions from energy taxation for biofuels (Directive, 2003/96/EC). The aims of the recently released European Parliament and the Council directive on the promotion of the use of energy from renewable sources amending and subsequently repealed Directives 2001/77/EC and 2003/30/EC (Directive 2009/28/EC); are to achieve by 2020 a 20% share of energy from renewable sources in the EU's final consumption of energy and a 10% share of energy from renewable sources in each member state's transport energy consumption. Moreover the GHG emission saving from the use of biofules and bioliguids shall be at least 35%, 50% in 2017 and 60% in 2018 yrs. The aim of this review is an evaluation into the current knowledge of carbon sequestration and to present potential bioenergy crops for carbon sequestration in Poland.
Information 
Anbieter/Quelle 
Material 
Beurteilung