Selections of Broad-leaved Tree Species Planting in Chinese Fir Degraded Plantation Forests:Based on Carbon Stock,Productivity and Carbon-sink Economy
[Objective]Continuous cultivation of pure Chinese fir(Cunninghamia lanceolata)leads to soil degradation and reduced productivity.Mixed planting broad-leaed trees with Chinese fir can improve stand quality and productivity.This study aimed to investigate the carbon stock,productivity,and economic value of carbon sinks under the mixed mode of different broadleaf species and Chinese fir,as well as to provide technical support for the selection of broad-leaved tree species for high-efficiency carbon sink forests con-struction of degraded Chinese fir plantation forestsin south China.[Method]In this study,10 stands of dif-ferent broadleaf species mixed with Chiense fir,planted in 2004,were utilized to study the differences in carbon stocks,productivity,and economic value of carbon sinks of the stands under different mixing pat-terns.[Result]The results showed that:(1)Significant differences were detected in the diameter at breast height(6.5～21.3 cm),tree height(8.0～22.6 m),and stand density reduction(750～3 119 plant·hm-2)among 10 broad-leaved species.Mytilaria laosensis had the highest values,which were significantly high-er than Michelia maudiae(p＜0.01).Furthermore,the Mytilaria laosensis had the largest proportion of large-diameter trees,whereas the remaining 9 species were primarily medium-diameter.(2)The stem,branch,leaf,root,and total biomass of different stands ranged from 56.54 to 140.69,13.22 to 43.97,2.72 to 9.17,3.22 to 80.35,and 82.78 to 274.18 t·hm-2,respectively,and all showed significant differences(p＜0.01).Among these five biomass indicators,the largest tree species were Mytilaria laosensis,while the smallest tree species were different.Cinnamomum burmanni had the smallest biomass of stem,leaf,and total biomass,whereas Michelia odora and Castanopsis hystrix had the smallest biomass of branch and root,respectively.(3)The carbon stocks,productivity and economic value of carbon sinks of the 10 tree species varied from 15.43 to 136.66 t·hm-2,1.62 to 14.38 t·hm-2·a-1,and 0.18 to 23.9 million yuan·hm-2,re-spectively.Carbon stocks were substantially greater in Mytilaria laosensis,compared with Michelia odora and Michelia maudiae(p＜0.01).The productivity of Mytilaria laosensis was significantly higher than that of the other tree species,except for Schima superba(p＜0.01).Additionally,the economic value of carbon sink was significantly higher for Mytilaria laosensis compared with the other tree species,except for Schi-ma superba and Liquidambar formosana(p＜0.01).[Conclusion]In summary,in the transformation of de-graded Chinese fir plantation forests in northern Guangdong,it is recommended to prioritize the selections of Mytilaria laosensis,Schima superba,and Liquidambar formosana as tree species for high-efficiency car-bon sink forests,whereas when cultivating large-diameter timber forests,it is recommended to prioritize the selections of Mytilaria laosensis,Michelia chapensis,Cinnamomum burmanni,and Castanopsis hystrix.
Cunninghamia lanceolataDegraded plantation forestsCarbon stockForest productivityEconomic value of carbon sinks
万方数据
维普
