Study On Net Productivity Of Quercus Mongolica Forests,Larix Olgensis Forests In Eastern Liaoning Provinceand Pinus Tabulaeformis Forests In Western Liaoning Province

Forest productivity can directly reflect the forest production capacity under natural environmental conditions,characterize the quality of forests,and can also be used as an important factor to measure the ability of forest ecosystems to cope with climate change.The maintenance of forest productivity and related functions closely link to economic and social sustainability,and forest productivity assessments were included in the forestry《Agenda 21》.Taking natural secondary forests of Mongolia oak（Quercus Mongolia）,Larch（Larix olgensis）artificial forests in eastern Liaoning Province and Pine（Pinus tabulaeformis）artificial forests in western Liaoning Province as the research object,the net productivity model was established,and the NPP values of three forest stands were estimated,to provide basic scientific data in studies of the global carbon cycle and carbon management.The results showed that the average annual productivity of Mongolia oak in eastern Liaoning province showed that the maximum of young forest was 12.43 t·hm^-2·a^-1,and the shrub productivity of young forest was 0.27 t·hm^-2·a^-1.The maximum was 4.45 t·hm^-2·a^-1;the productivity of Mongolia oak community was 17.15 t·hm^-2·a^-1for young forests and 7.93 t·hm^-2·a^-1for middle aged forests;The average annual productivity of Larch artificial forests showed that the young forest was 7.87 t·hm^-2·a^-1,the shrub productivity mature forest was 0.67 t·hm^-2·a^-1,and the herbaceous productivity middle forest was 3.04 t·hm^-2·a^-1;Larch community productivity middle aged forest maximum 8.76 t·hm^-2·a^-1,near-mature forest minimum 4.46t·hm^-2·a^-1;Pine artificial forests plantation productivity 1.69～1.85 t·hm^-2·a^-1,the highest in near-mature forest,the shrub productivity near-mature forest was 0.06 t·hm^-2·a^-1,and the herbaceous productivity youngest forest was0.78 t·hm^-2·a^-1;Pine community productivity near-mature forest maximum 2.64 t·hm^-2·a^-1,mature forest minimum 2.02 t·hm^-2·a^-1。...