生物炭和炭基肥施用对绿地土壤性质及大叶罗勒生长特性的影响

Effects of biochar and biochar-based fertilizer to green space soil properties and growth of Ocimum basilicum var.majus

城市绿地土壤理化性质退化是城市绿化景观效果提升的主要障碍因子,生物炭和炭基肥施用可有效提高农田土壤肥力和作物产量,但生物炭和炭基肥对城市绿地土壤肥力和绿化植物生长的影响目前还不明确。采用盆栽试验,分别设置生物炭和炭基肥添加0%、0.5%、1%、2%、4%和6%的处理,探究不同用量生物炭和炭基肥施用对绿地土壤物理、化学性质以及大叶罗勒生长的影响。结果表明,与对照相比,添加生物炭降低了土壤容重,而炭基肥对土壤容重影响较小。添加生物炭对土壤pH无显著影响,而添加炭基肥能显著降低土壤pH 0.23~1.09个单位;添加生物炭对土壤碱解氮无显著影响,而添加炭基肥显著增加土壤碱解氮含量4.78~53.55 mg/kg;生物炭和炭基肥均能显著增加土壤有效磷含量,增加幅度分别为1.26~6.05和1.11~8.51 mg/kg;生物炭和炭基肥增加土壤速效钾的幅度分别为22.6~326.9和43.2~174.7 mg/kg。添加生物炭和炭基肥后土壤阳离子交换量较对照分别升高了0.79~1.27和1.16~2.42 cmol/kg。与对照相比,炭基肥能提高大叶罗勒叶绿素含量,生物炭对大叶罗勒叶绿素含量无显著影响。生物炭添加量大于1%时大叶罗勒生物量显著增加,炭基肥添加量小于2%时大叶罗勒生物量显著增加。因此,添加生物炭具有改善绿地土壤物理性质;生物炭和炭基肥均能提高土壤保肥性,改善土壤性状;生物炭和炭基肥均能提高土壤速效氮磷钾养分含量;综合作物生长,推荐炭基肥用量不能超过1%,而生物炭改良园林土壤可与适量氮肥配合施用以增加绿化植物叶绿素含量和观赏性。

Soil physical and chemical index deterioration of urban green space is the main obstacle factor of urban green landscape beautification.Biochar and biochar-based fertilizer application can effectively improve the production of soil fertility and crop yield of farmland,but the effect of biochar and biochar-based fertilizer on urban green space soil fertility and green plant growth is still not clear.A pot experiment was conducted to evaluate the effect of biochar and biochar-based fertilizer and their application rates 0%,0.5%,1%,2%,4%and 6%on soil physical and chemical properties and growth of Ocimum basilicum var.majus.The results showed that biochar significantly decreased soil bulk density,while biochar-based fertilizer had no effect on soil bulk density as comparing with the control.There was no significant difference in soil pH after amending with biochar,while biochar-based fertilizer markedly decreased soil pH by 0.23~1.09 units.Biochar-based fertilizer amendment treatments significantly increased soil available N by 4.78~53.55 mg/kg than that of the control,while biochar treatments had no difference with the control treatment.There was significant increase in soil available phosphorus by 1.26~6.05 and 1.11~8.51 mg/kg for biochar and biochar-based fertilizer treatments,respectively.There was also significant increase in soil available potassium by 22.6~326.9 and 43.2~174.7 mg/kg for biochar and biochar-based fertilizer treatments,respectively.As compared with the control,both biochar and biochar-based fertilizer treatments significantly increased soil cation exchangeable capacity by 0.79~1.27 and 1.16~2.42 cmol/kg,respectively.Biochar-based fertilizer treatments significantly increased chlorophyll content of O.basilicum var.majus compared to the control,and biochar had no significant effect on the content of chlorophyll.When the amount of biochar was more than 1%,the biomass of the O.basilicum var.majus increased significantly,and the biomass of the O.basilicum var.majus significantly increased when the biocharbased fertilizer was less than 2%.The results indicated that biochar and biochar-based fertilizer could effectively improve soil physical property,and both amendments could improve soil available nutrients and nutrient preserving capability.Taking the plant growth into consideration,1%of biochar-based fertilizer was recommended under the conditions of this experiment.