Effect Of Liberation Cutting Intensity On The Carbon Storage And Annual Net Carbon Sequestration Of Korean Pine Forests By Planting Conifer And Reserving Broad-leaved Tree In Xiaoxing’an Mountains Of China

To reveal the influence rule of Liberation Cutting intensity on the medium term carbon sink of Korean Pine forests by planting conifer and reserving broad-leaved tree(PCRBT),and to provide basis for the restoration of zonal climax vegetation broad-leaved Korean pine forest(White birch Korean pine forest,Populus Korean pine forest,Quercus mongolica Korean pine forest).The carbon storage(vegetation and soil),vegetation net annual carbon sequestration(ANCS)of the mid-term(35a)Korean pine forests by PCRBT under the different Liberation Cutting(LC)intensity(control(C),Low-intensity LC(L)-1/7,moderate-intensity LC(M)-1/5,and High-intensity LC(H)-1/4(volume ratio))were measured simultaneously by using the relative growth equation and carbon/nitrogen analysis method in temperate Xiaoxing’an Mountains of China,to reveal the law and mechanism of the effect of the Liberation Cutting on the carbon sink of the Korean Pine Forest.The results show that:After liberation cutting 30 years of the White birch Korean pine forest,the vegetation carbon storage(81.15±3.63～85.48±2.30 t.hm-2)of the Korean Pine Forests by PCRBT were significantly lower than that of control treatment(100.24±1.10 t.hm-2)by 14.7%-19.0%but the difference of vegetation carbon reserves was not significant among the low-,medium-,and high-intensity liberation cutting.The soil carbon storage(108.32±6.27～121.42 ± 11.75 t·hm-2)of the Korean Pine Forests by PCRBT were similar to that of control(-8.4%～2.7%,P>0.05),however,the spatial distribution patterns of soil carbon storage were changed by the liberation cutting.The carbon storage of ecosystem(189.47±5.16～218.44±0.65 t·hm-2)of the Korean pine Forest by PCRBT has been recovered under low intensity LC(-5.3%,P>0.05),but moderate-intensity and High-intensity LC still made them significantly lower than that of the control by 9.3%and 13.3%(P<0.05),and the carbon storage distribution ratio of the ecosystem were slightly changed by all the three intensity LC treatments(the carbon storage ratio of vegetation was reduced by 3.06%～4.57%).The ANCS(3.72±0.37～4.42±0.37 tC.hm-2·yr-1)of the Korean pine forest under low intensity liberation cutting treatment have been restored(-9.7%,P>0.05),while moderate-intensity and High-intensity liberation cutting still made them significantly lower than that of the control by 14.0%～15.8%(P<0.05),but there was no significant difference among the different liberation cutting intensity treatments.After liberation cutting 30 years of the Populus Korean pine forest,the vegetation carbon storage(58.79±8.75～85.67±4.77 t·hm-2)was significantly reduced by 28.0%～31.4%by different liberation cutting intensities,but there was no significant difference among different liberation cutting intensities.Soil carbon storage(111.8±7.6～133.3±13.5t·hm-2)was increased by 13.4%and 18.7%compared with the control under M,while that under moderate and intense liberation cutting was similar to that of the LC.Among the three kinds of liberation cutting intensity treatments,the M and H increased by 14.0%and 19.2%compared with the L,and showed an increasing trend with the increase of L.L,M and H restored the ecosystem carbon storage(173.47±13.19～197.99±12.93 t·hm-2),and changed the proportion of carbon storage(vegetation carbon storage decreased 7.71%～12.67%).L,M and H restored the VNCS(2.88±0.23～3.05±0.28 tC·hm-2.yr-1),and there was no significant difference in the intensity of light transmittance.After liberation cutting 25 years of the Quercus mongolica Korean pine forest,the vegetation carbon storage of the middle stage(47.52±1.38～71.59±3.86t·hm-2)was significantly reduced by 19.3%-33.6%,the M and H was still significantly lower than L by 14.0%and 17.7%.Soil carbon storage(64.67±13.18～76.54±18.66t·hm-2)was slightly higher than that of the control under L,M and H.Among the three kinds of light penetration intensity treatments,moderate and intense liberation cutting increased by 1.8%and 9.3%compared with mild liberation cutting intensity,and showed an increasing trend with the increase of liberation cutting intensity.L,M and H restored the carbon storage(120.96±3.82～136.26±9.72 t·hm-2),and changed the proportion of carbon storage(vegetation carbon storage decreased 7.33%～14.24%).The distribution of VNCS were 1.66±0.15-2.05±0.30 tC·hm-2·yr-1 under light transmittance treatment.The VNCS under light transmittance treatment were slightly lower than those of the control,but the difference was not significant.The VNCS under light transmittance treatment were 18.2%and 19.0%lower than those of the control.However,there was no significant difference in VNCS among different liberation cutting intensities.