Forests in Serbia as the Factor of Environment Protection in the Conditions of Global Climate Changes

Transcription

1 Forests in Serbia as the Factor of Environment Protection in the Conditions of Global Climate Changes Stanimir Kostadinov Belgrade University, Faculty of Forestry Kneza Višeslava 1, Belgrade, Serbia

2 CLIMATE CHANGES IN SERBIA In the study ''Regional climate model: impact of climate change for soil erosion and conservation in central Serbia'' (Kadović et al., 2013), using CRCM (Coupled Regional Climate Model) was analysed climat in different periods : Period Годишња промена температуре +1,0-1,1 o C падавина +5-10% Годишња промена

3 Period Годишња промена температуре +3,6-3,8 o C Годишња падавина -5-10% промена

4 Based on the climate changes which could be expected, it is almost certain that in the near future in our geographic latitudes it would come to: increase in the air temperature; decrease of precipitation; aggravation of physical characteristics of the soil; increased tendency to soil erosion ; decrease in vegetation s protective role; worsen conditions of natural and artificial revival of vegetation All this will have the direct and indirect influence to the intensifying and spreading of all kinds degradation processes.

5 Forest ecosystems belong to the natural systems which have been estimated as to be exposed to unfavorable effects of climate changes in almost all parts of the world.

6 Forests in Serbia Forests are an important component of the global carbon cycle, either as the source or accumulator of carbon. Their potential in the efforts that are being taken to mitigate global climate change and protect the environment has been characterized as high. Forests represent the most significant type of vegetation in terms of a net source of carbon, carbon sequestration and retention in land. Also forests are the most important component for soil and water protection against degradation, first of all against soil erosion ( water and wind erosion).

7 Table 1 Land use in Serbia Land use Area ha % Forests 2,252, Other wooded land 382, Barren land 92, Agricultural land 3,594, Meadows and pastures 1,029, Built-up area 312, Inland water 85, Total 7,748,

8 According to the first reports of the Republic of Serbia to the United Nations Framework Convention on Climate Change (2010) regarding the emissions of CO2 from fossil fuel combustion the effect of forests for CO 2 sequestration was 11.41% in Taking into account the data, the annual potential of forests for CO 2 absorption for the year 2012 is 18.8%, according to the baseline scenario of emissions from fossil fuel combustion, and 19.1% according to the alternative scenario. Assuming that the program of afforestation in Serbia is implemented by 2015, with an increase of 100,000 hectares of new forests, the potential for CO 2 absorption will have increased to up to 14,512 Gg per year, and according to the baseline scenario of emissions from the combustion of fossil fuels for 2015 that would amount to 21.0% and 22.8% according to the alternative scenario.

9 As forests are gaining increasing importance as a means of carbon sequestration, future forest management systems are likely to be evaluated with regard to their effectiveness in the fulfillment of this function. This will result in the silviculture of pro-c forests (for carbon sequestration from the atmosphere). The adoption and implementation of such a long-term policy will create additional benefits for other environmental goals, including the protection of biological, water and land resources.

10 Table 2. Distribution of water erosion processes in Serbia Category Erosion Processes Intensity Area km 2 % I Excessive Erosion 2, II Intensive Erosion 9, III Medium Erosion 19, IV Weak Erosion 43, V Very weak Erosion 13, Total 88, Source: Kostadinov et al, 2006a

11 19 00 ' ' ' ' ' ' ' ' ' WATER MASTER PLAN ' ' REPUBLIC OF SERBIA EROSION MAP LEG EN D EROSIO N CATEGORY I EKSC ESI VEERO SION SP ECIFIC PRODUCTI ON Z= Ws p> 3300 m / km / year II STRONG ERO SION SP ECIFIC PRODUCTI ON Z= Ws p= 1800 m / km / year I II M ED IUM ERO SION SPEC IFI C PRODUCTIO N Z=0.55 Ws p= 950 m 3/ km 2/ yea r IV SMALL ERO SION SPEC IFI C PRODUCTIO N Z=0.30 Ws p= 400 m 3/ km 2/ yea r V M INIM UM ERO SION SPECI FI C PRO DUCTIO N Z= Wsp= 80 m / km / year ' NOVI S AD ' ' km B EOGR AD ' ' ' ' ' ' NI[ ' ' ' ' ' ' ' ' Ins titute for D ev elopment of Wa ter Res our ce "Ja roslav Cerni" ' ' ' ' ' '

12 Damages caused by erosion and torrents a) General damages - Soil loss - Water loss - Disturbance of runoff regime ( torrential floods) - Reservoir siltation - Irrigation and drainage systems siltation b) Ecological effects On-site effects - Environment degradation Off-site effects - Mechanical pollution of water in the streams and reservoirs - Chemical pollution of water by manures and fertilizers - Chemical pollution by pesticides

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15 Rill erosion on arable land

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18 Effect Of Forest Cover On The, Soil Erosion And Sediment Transport In Mountainous Watersheds The researches were caried out in three small experimental watersheds in West Serbia: Dubošnički Potok, Lonjinski Potok and Đurinovac Potok. All the three experimental watersheds are the right tributaries of the river Drina and they are torrential streams. The watersheds are situated on the territory of the community Ljubovija in West Serbia. The main watershed parameters are given in Table 4 (Kostadinov, 1994, 1996).

19 Table 4. Parameters of the watershed areas Parameters Symbol Dubošnički Potok Lonjinski Potok Đurinovac Potok Watershed area F km Watershed perimetre O km Watershed length L gl km Drainage density G km km Mean elevation of the watershed area Mean slope of the watershed area N sr m I sr % Stream-bed slope I t % Erosion coefficient Z

20 The vegetative cover, i.e. land use, is different in the three experimental watersheds. As it can be seen, in the Lonjinski Potok watershed 70.35% area is under well-stocked forests, in the Dubošnički Potok watershed 48.52%, and in the Đurinovac Potok watershed 39.5%. The vegetative cover in all the three watersheds has the same characteristics. Significant areas are covered by very degraded forests transformed into very thin brushwood of eastern hornbeam, ash and oak, where very strong rill erosion occurs.

21 Table 6. Annual characteristics of rainfall and sediment transport NAME OF DRAINAGE BASIN YEAR PRECIPITATION H year mm SEDIMENT TRANSPORT h max M R M V M G m 3 km -2 DUBOŠNIČKI POTOK average value LONJINSKI POTOK average value DJURINOVAC POTOK

22 Discussion of the Results The results of the research show that forest cover has a considerable effect on the formation of the runoff regime from the watershed. With all the other conditions being equal or similar (rainfall, relief, parent rock, soil) in Lonjinski Potok (70% of the watershed area under well-stocked forest) there is a balanced regime of runoff whereas the torrents Đurinovac Potok (39.5% of watershed under forest) and Dubošnički Potok (48.5% under forest) have unbalanced regime of runoff. Runoff in those two watershed was discontinuous with large intervals of drought and the discharge was mainly in the form of flood waves.

23 The specific mean annual transport of total sediment transport in the Lonjinski Potok (70% of watershed under well-stocked forest) was 4.5 times lower than in the Dubošnički Potok (48.5% under forest) and 3.5 times lower than in the Đurinovac Potok (39.5% under forest). Such a degree of forest cover in a watershed dominates, energetic potential of the watershed (relief) and the erosion activity of rainfall, which has been proved by the example of the Lonjinski Potok watershed. All the above proves that forest cover is a powerful means of flood peaks control (water conservation), soil erosion intensity and sediment transport in the small mountainous watershed.

24 Effect of afforestation of bare land in the Vlasina river watershed

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26 Conclusion Woodland area in Serbia equals 29.6% of total territory, which is considerably less than optimum woodiness of 41.4%. Insufficient afforestation is one of the reasons for intensive degradation of soil and water (water and wind erosion) in Serbia. Researches conducted in experimental watersheds in Serbia confirmed that forests are powerful when it comes to obtaining balanced runoff regime and successful erosion control. Forests in Serbia, as well as other ecosystems, are under the influence of global climate changes which are present in the last years, and they could present even greater danger according to some scenarios. In order to mitigate the influence of global changes in Serbia, it is necessary to improve the existing woodland, afforest greater areas until optimum woodiness (41.4%) is reached and to afforest areas around cities and industrial zones. Increase in woodland areas will reduce soil erosion, sediment transport and all the damages caused by these processes to agriculture, water management and other branches of the economy.

27 Thank You!