地表覆盖方式对广西柑橘果园土壤水分特征的影响

【目的】探究不同覆盖方式对广西柑橘果园土壤性质及土壤水分变化的影响,为该区域果园杂草管理及水分管理提供参考依据。【方法】以广西柑橘果园为研究对象,设喷施除草剂对照(CK)、防草布覆盖(GPC)和自然生草割刈(NGM)3种果园地表覆盖处理,并于处理一年后测定0~10 cm、10~30 cm、30~50 cm和50~70 cm土层的土壤基本理化性质和果园土壤水分变化特征。【结果】不同地表覆盖处理对柑橘果园表层0~10 cm土壤的容重、总孔隙度和有机质含量有明显影响,对深层土壤影响较小。NGM处理使0~10 cm土层土壤容重显著降低7.52%(P<0.05,下同),土壤有机质含量提高7.99%;GPC处理使0~10 cm土层土壤容重降低3.01%,土壤有机质含量降低14.15%。相同土壤水吸力下,0~10 cm和10~30 cm土层土壤含水量表现为GPC>CK>NGM;30~50 cm土层表现为CK≈GPC>NGM;50~70cm土层表现为CK>NGM>GPC。在0~10 cm土层中,NGM处理的速效水含量(0.079 cm3/cm3)最高;在30~50 cm和50~70 cm土层,GPC处理的速效水含量最高,分别较CK提高11.00%和18.12%。GPC和NGM处理均可提高各土层的土壤含水量,其中GPC处理0~10 cm和10~30 cm土层含水量增幅更大,而NGM处理30~50 cm和50~70 cm土层含水量增幅更明显。GPC和NGM处理均可显著提高0~70 cm各土层土壤贮水量,其中GPC处理提高2.83%~4.26%,NGM处理提高4.02%~4.55%。【结论】自然生草割刈处理在改善柑橘园表层土壤环境、增强土壤蓄水保墒和供水能力方面具有较好的效果,而防草布覆盖处理在保水方面也有较大优势。在生产中建议采用自然生草割刈的管理方式。

Effects of mulching pattern on soil moisture characteristics in Guangxi citrus orchard

【Objective】To explore effects of mulching pattern on soil property and soil moisture in Guangxi citrus orchard,and to provide a theoretical basis for orchard weed and moisture management in this orchard.【Method】Taking a citrus orchard in Guangxi as research object,3 treatments,spraying herbicide(CK),grass-proof cloth coverage(GPC) and natural grass mowing(NGM) were set. After one year of treatment,basic soil physicochemical properties and soil moisture characteristics of the orchard at layers of 0-10 cm,10-30 cm,30-50 cm and 50-70 cm were measured.【Result】Different mulching treatments had significant effects on bulk density,total porosity and organic matter content of the surface soil(0-10 cm),but no significant effects on the deep soil layers. In 0-10 cm soil layer,NGM treatment significantly(P<0.05,the same below) reduced soil bulk density by 7.52% and increased soil organic matter by 7.99%;GPC treatment reduced soil bulk density by 3.01% and soil organic matter by 14.15%. Under the same soil suction,the soil moisture content in 0-10 cm and 10-30 cm soil layers was in the order of GPC>CK>NGM;in 30-50 cm soil layer was CK≈GPC>NGM;and in 50-70 cm soil layer was CK>NGM>GPC. In 0-10 cm soil layer,the highest available water content(0.079 cm3 /cm3 ) was found in NGM treatment;in 30-50 cm and 50-70 cm soil layers,the highest available water content was found in the GPC treatment,which was 11.00% and 18.12% higher than that in CK,respectively. Both GPC and NGM treatments could increase soil moisture content in each layer,and the soil moisture content in 0-10 cm and 10-30 cm layers under GPC treatment had a higher increase,while the soil moisture content in 30-50 cm and 50-70 cm layers under NGM treatment had a greater increase. GPC and NGM treatments could significantly increase soil moisture storage capacity in 0-70 cm layer,in which GPC treatment brought an increase of 2.83%-4.26%,and NGM treatment 4.02%-4.55%.【Conclusion】Natural grass mowing treatment has a good effect on surface soil environment improvement,soil moisture storage and water supply capacity enhancement of citrus orchard,and it also has great advantages of water conservation. Therefore,it is suggested to adopt natural grass mowing management pattern in production.