To store or to drain - To lose or to gain? Rewetting drained peatlands as a measure for increasing water storage in the transboundary Neman River Basin.

Agriculture continues to place unwanted pressure on peatland functionality, despite international recognition calling for their conservation and restoration. Rewetting of peatlands is often the first step of restoration that aims towards improving the delivery of ecosystem services and their benefits for human well-being. Ongoing debates on peatland restoration in agricultural landscapes raise several issues based on the valuation of benefits achieved versus the costs of peatland restoration. Using the transborder Neman River Basin in North-Eastern Europe, this study aimed to quantify and evaluate the gains provided by peatland rewetting. To achieve this, this study estimated i) possible changes in water storage capacity from peatland restoration, ii) the value of expected benefits from restoration and iii) costs of restoration measures at the overarching basin level. Applying multiple assumptions, it was revealed that rewetting drained peatlands in the Neman River Basin could increase water retention by 23.6-118 M m3. This corresponds to 0.14-0.7% of the total annual Neman River discharge into the Baltic Sea. Unit increase of water retention volume due to rewetting ranged between 69 and 344 m3·ha-1. The estimated water retention value ranged between 12 and 60.2 M EUR·year-1. It was also shown that peatland rewetting at the scale of Neman River Basin would cost from 6.8 M and 51.5 M EUR·year-1 depending on the selected scenario. Applying less expensive rewetting measures (non-regulated outflow from ditch blocks), the economic gains (as water storage ecosystem service of rewetted peatlands) from rewetting exceed the costs of rewetting. Thus, rewetting peatlands at a river-basin scale can be considered technically and economically efficient measures towards sustainable management of agricultural landscapes. The novel methodology applied in this study can be used when valuing trade-offs between the rewetting of drained peatlands and leaving them drained for the uncertain future of wetland agriculture.

The role of vitamin D in health preservation and exertional capacity of athletes.

Sports training causes an increased load on the musculoskeletal, hormonal and immune system, which makes maintaining homeostasis in the organism more difficult. Maintaining metabolic balance in the athlete's body is important due to the necessity to obtain high physical fitness. One factor that facilitates optimization of health and increased endurance is a balanced diet. Proper nutrition enables provision of energy-giving and body-building substances as well as bioelements and vitamins, which influence metabolic processes and play regulatory functions. Vitamin D, also called calciferol, has an impact on maintaining effectiveness of the musculoskeletal system, on mineralization of bones and on increase of mass, strength and endurance of muscles. An association between vitamin D content in the organism and levels of anabolic hormones such as insulin and testosterone has been reported. A sufficient amount of calciferol is also necessary for effective functioning of the nervous system, including keeping balance and determining the reaction time. Maintaining an adequate vitamin D level in the athlete's body is also important due to its role in mobilizing the immune system and preventing infections, to which athletes are particularly prone. The positive impact of vitamin D on physical fitness of athletes shows how important it is to maintain its adequate level in the organism. Numerous studies indicate widespread occurrence of vitamin D deficiency, including among athletes. Climatic conditions and training in halls lead to limited endogenous production of this vitamin, which shows the importance of diet as a source of vitamin D. The aim of the study is to present the role of vitamin D in preservation of health, particularly endurance and physical fitness of athletes, on the basis of currently available scientific literature.