外源碳输入对烤烟光合特性及土壤有机碳组分的影响

Effects of exogenous carbon input on photosynthetic characteristics and soil organic carbon fractions of flue-cured tobacco

以烤烟品种‘K 326’为供试材料,采用土培盆栽试验,研究了添加不同种类生物炭及高碳基修复肥对烤烟叶绿素含量、光合气体交换参数、各器官干物质积累及土壤有机碳组分含量变化的影响。结果表明,添加外源碳处理的烟株净光合速率显著增加,其中以高碳基土壤修复肥(T4)增加比例最高,达到35.84%。3种外源碳处理的总生物量分别比对照增加了1.51倍(T4)、1.00倍(T2)和56.92%(T3)。不同种类外源碳能够显著提高土壤有机碳组分含量,外源碳处理的总有机碳(TOC)含量分别比对照增加了94.18%(T4),53.69%(T2),29.16%(T3);易氧化态碳(ROC)含量分别比对照增加了25%(T2),26.52%(T3),56.82%(T4);可溶性有机碳(DOC)含量以T4处理增加比例最高,达到45.44%,微生物量碳(MBC)含量最大值也出现在T4处理。综合而言,施用外源碳增加了叶片光合色素含量,提高了烟株的光合生产能力,促进了光合产物积累,并有利于土壤有机碳的积累,改善土壤微生态环境,提高土壤肥力,进而达到固碳增产的目的。

The effects of adding different kinds of biochar and high carbon based soil repair fertilizer on chlorophyll content,photosynthetic physiological index,dry matter accumulation in various organs and soil organic carbon fractions of flue-cured tobacco cultivar‘K326’were studied by pot experiment.The results showed that thenet photosynthetic rate(Pn)was significantly improved by application of exogenous carbon,and the highest increase rate reached 35.84%appeared in high carbon based soil remediation fertilizer treatment.The dry matter accumulation of three exogenous carbon treatments was higher than the control,respectively increased by 1.51 times(T4:High carbon based fertilizer add conventional fertilizer application),1.00 times(T2:Peanut shell biochar add conventional fertilizer application)and 56.92%(T3:Rice husk biochar add conventional fertilizer application).The content of soil organic carbon fractions was significantly increased in the different treatments of exogenous carbon.Compared with control,the total organic carbon(TOC)content increased by 94.18%(T4),53.69%(T2)and 29.16%(T3),respectively.The content of readily oxidizable organic carbon(ROC)increased by 25%(T2),26.52%(T3)and 56.82%(T4),respectively.The highest increase proportion of dissolved organic carbon(DOC)was 45.44%in the T4 treatment of high carbon based restoration fertilizer(T4),and the maximum content of microbial biomass carbon(MBC)also appeared in the T4 treatment of high carbon based soil repair fertilizer.In conclusion,the application of exogenous carbon could increase the content of photosynthetic pigment,improve the photosynthetic performance,and eventually promote the accumulation of photosynthetic products eventually.Meanwhile,the exogenous carbon,as a positive role in improving soil micro ecological environment,was beneficial to the accumulation of soil organic carbon and the carbon fixation and yield increase.