Determination of biomass, minerals content and depletion of nutrients as a result of different systems of utilisation in clear-cut Scots Pine forests prof. dr hab. Roman Gornowicz mgr inż. Krzysztof Polowy Poznan University of Life Sciences, Poland
Plan of the presentation 1. The purpose of the study 2. Study area 3. Results 4. Conclusions
The purpose of the study Determination of dry mass of different tree parts Determination of mineral content of different tree parts Calculation of mineral loss as a result of different harvesting systems Determination of mineral capital of soil Calculation of rate of nutrient loss in relation to soils nutrient capital
Study area Nadleśnictwo Bolewice
Study area mature clear-cut stands Scots Pine (Pinus sylvestris L.) 95-year-old forest site type: coniferous fresh site
Division of a tree 1. Wood 2. Bark 3. Branches 4. Needles 5. Roots
Results dry mass distribution of dry mass [%] Fresh mass of the stand 327 Mg/ha Dry mass of the stand 154 Mg/ha 5,8 1,9 11,0 16,7 64,6 stem wood bark branches needles roots
Results Humidity 160,00 Average relative and absolute humidity [%] of the analysed tree parts 140,00 132,15 136,69 139,94 120,00 100,00 80,00 109,50 82,74 average relative humidity 60,00 40,00 51,08 42,80 56,25 57,68 57,81 average absolute humidity 20,00 0,00 stem wood stem bark branches needles stump and roots
Results 800,00 700,00 Average weight of one tree divided into different tree parts [kg] 722,60 600,00 500,00 400,00 467,10 340,20 fresh 300,00 200,00 224,30 dry 100,00 0,00 24,00 35,00 79,70 41,60 13,50 5,70 120,7051,20 stem wood stem bark branches needles stump and roots total
Results minerals content Nitrogen [% d. m.] 1,6000 1,4000 1,2000 1,0000 0,8000 0,6000 0,4000 0,2000 0,0000 0,1108 0,1797 0,3278 0,3372 0,2053 0,2170 1,2107 1,3767 0,1622 0,1855 stem wood stem bark branches needles stump and roots lowest mean value on the plot highest mean value on the plot
Results minerals content Phosphorus [% d. m.] 0,3000 0,2500 0,2613 0,2000 0,1500 0,1000 0,2245 lowest mean value on the plot highest mean value on the plot 0,0500 0,0000 0,0192 0,0263 0,0117 0,0208 0,0173 0,0193 0,0163 0,0158 stem wood stem bark branches needles stump and roots
Results minerals content Potassium [% d. m.] 0,7000 0,6000 0,5717 0,5000 0,4000 0,3000 0,2000 0,4108 lowest mean value on the plot highest mean value on the plot 0,1000 0,0000 0,0308 0,0183 0,0833 0,0858 0,0708 0,0595 0,0383 0,0295 stem wood stem bark branches needles stump and roots
Results minerals content Calcium [% d. m.] 0,9000 0,8000 0,7867 0,7000 0,6000 0,5000 0,4000 0,3000 0,2000 0,1000 0,0000 0,0925 0,1233 0,4608 0,2333 0,2883 0,3417 0,3800 0,0650 0,0755 stem wood stem bark branches needles stump and roots lowest mean value on the plot highest mean value on the plot
Results minerals content Magnesium [% d. m.] 0,0700 0,0648 0,0600 0,0500 0,0400 0,0528 0,0540 lowest mean value on the plot 0,0300 0,0200 0,0210 0,0340 0,0232 highest mean value on the plot 0,0100 0,0157 0,0160 0,0120 0,0000 0,0065 stem wood stem bark branches needles stump and roots
Results minerals content Sodium [% d. m.] 0,0500 0,0450 0,0400 0,0350 0,0300 0,0250 0,0200 0,0150 0,0100 0,0050 0,0000 0,0038 0,0078 0,0162 0,0263 0,0027 0,0072 0,0247 0,0468 0,0037 0,0068 stem wood stem bark branches needles stump and roots lowest mean value on the plot highest mean value on the plot
Systems of utilisation utilisation of stem wood only stem wood with the bark all the aboveground parts of the tree whole tree
Systems of utilisation utilisation of stem wood only stem wood with the bark all the aboveground parts of the tree whole tree
Systems of utilisation utilisation of stem wood only stem wood with the bark all the aboveground parts of the tree whole tree
Systems of utilisation utilisation of stem wood only stem wood with the bark all the aboveground parts of the tree whole tree with stump and roots
Results nutrient loss 300 250 Nitrogen [kg/ha] 237,97 278,76 200 150 133,96 169,97 100 50 0 stem wood stem wood in bark aboveground tree parts whole tree with stump and roots
Results nutrient loss 35,00 30,00 25,00 Phosphorus [kg/ha] 26,50 30,27 20,00 15,00 10,00 5,00 14,53 17,10 0,00 stem wood stem wood in bark aboveground tree parts whole tree with stump and roots
Results nutrient loss 70,00 60,00 50,00 Potassium [kg/ha] 57,17 64,97 40,00 30,00 20,00 10,00 24,33 32,54 0,00 stem wood stem wood in bark aboveground tree parts whole tree with stump and roots
Results nutrient loss 250,00 200,00 150,00 Calcium [kg/ha] 165,70 217,20 233,56 100,00 105,11 50,00 0,00 stem wood stem wood in bark aboveground tree parts whole tree with stump and roots
Results nutrient loss 35,00 30,00 25,00 Magnessium [kg/ha] 22,38 27,30 29,15 20,00 18,45 15,00 10,00 5,00 0,00 stem wood stem wood in bark aboveground tree parts whole tree with stump and roots
Results nutrient loss 12,00 10,00 8,00 Sodium [kg/ha] 7,74 9,36 10,49 6,00 5,62 4,00 2,00 0,00 stem wood stem wood in bark aboveground tree parts whole tree with stump and roots
Results nutrient loss 300 250 200 150 100 50 0 stem wood stem wood in bark aboveground tree parts Nitrogen [kg/ha] Phosphorus [kg/ha] Potassium [kg/ha] Calcium [kg/ha] Magnessium [kg/ha] Sodium [kg/ha] whole tree with stump and roots
Soil analysis rate of nutrient loss in relation to soils nutrient capital for each soil horizon down to 50 cm
Soil analysis 4000 3500 3389,4 Average amounts of accesible nutrients in top soil to 50 cm [kg/ha] 3000 2500 2000 1500 1000 Nitrogen Phosphorus Potassium Calcium Magnesium 500 227 185,2 130,9 76 0 Organic carbon 63 903,3 kg/ha
Results 200,0 180,0 160,0 140,0 120,0 100,0 80,0 60,0 40,0 20,0 0,0 nutrient loss in relation to its content in the soil in different systems of utilisation [%] 80,3 126,6 165,9 178,4 35,9 30,9 35,1 38,4 29,4 24,3 13,1 17,6 4,0 6,4 5,0 7,5 11,7 13,3 7,0 8,2 stem wood stem wood in bark aboveground tree parts Nitrogen Phosphorus Potassium Calcium Magnessium whole tree with stump and roots
Conclusions Utilising the forest causes mineral withdrawal from the environment Limiting the harvesting scope to stem wood with the bark would significantly decrease mineral withdrawal Leaving the bark in the forest would especially save the calcium the question of practice and costs
Conclusions Stump lifting comparing to utilising aboveground parts of the tree does not increase the mineral loss significantly but serious considerations need to be made regarding physical damage to the soil.
THANK YOU FOR YOUR ATTENTION! Prof. dr hab. Roman Gornowicz mgr inż. Krzysztof Polowy