有机物料对山核桃林地土壤的培肥改良效果

Organic materials improved the soil fertility in Carya cathayensis forest lands

【目的】山核桃低产区和高产区林地土壤理化性状、肥力水平差异大,比较不同有机物料改良其土壤酸性、提高土壤肥力的作用,为合理施用有机物料提供依据。【方法】选择山核桃低产(红壤)和高产(石灰岩土)林地土壤进行室内培养试验。选取生物有机肥、黄腐酸钾、竹炭和沼渣4种有机物料,按质量1%的比例添加到供试土壤中,在25℃恒温条件下,在培养开始的0、30、60、90、180天,分别测定了土壤pH、碱解氮、有效磷、速效钾及有效态铁、锰、铜、锌的含量。【结果】1)红壤经180天培养后,发现有机物料对不同养分的作用不同。与对照相比,4种有机物料中仅沼渣处理的土壤碱解氮含量显著提高,高于对照52.85 mg/kg(P <0.05);4种有机物料都提高了土壤有效磷含量,其中生物有机肥和黄腐酸钾的作用明显高于竹炭和沼渣处理,分别高于对照13.21 mg/kg、12.07 mg/kg (P <0.05);4种有机物料处理都显著提高了土壤速效钾含量(P <0.05),黄腐酸钾的作用显著优于其它3种有机物料(P <0.05),高于对照136.00 mg/kg (P <0.05);4种有机物料中,仅黄腐酸钾处理的土壤有效铁含量显著提高,高于对照71.59 mg/kg (P <0.05);仅竹炭处理的土壤有效锌含量显著提高,高于对照0.94 mg/kg (P <0.05);而对有效锰、铜均无显著提升作用。2)石灰岩土培养180天后,4种有机物料对土壤碱解氮都无显著提升效果;但都显著提高了土壤有效磷水平,其中生物有机肥的作用显著高于其它3种有机物料(P <0.05),高于对照4.67 mg/kg (P <0.05);黄腐酸钾提高土壤速效钾的作用显著高于其它3种有机物料(P <0.05),高于对照94.00 mg/kg (P <0.05);仅生物有机肥和黄腐酸钾处理显著提高了土壤有效铁的含量,分别高于对照190.61 mg/kg、249.43 mg/kg (P <0.05);生物有机肥、黄腐酸钾、竹炭处理的土壤有效锰含量显著提高,分别高于对照135.74 mg/kg、155.96 mg/kg、51.51 mg/kg (P <0.05);仅生物有机肥和黄腐酸钾处理显著提高了土壤有效铜含量,分别高于对照1.79 mg/kg、2.99 mg/kg (P <0.05);但仅沼渣处理对土壤有效锌有显著提高作用,高于对照3.23 mg/kg (P <0.05)。3)在红壤(pH 4.46)中施用4种有机物料均提高了土壤pH,但仅沼渣处理的提升作用达显著水平,高于对照0.86个单位(P <0.05);同时,仅沼渣处理显著降低了红壤的土壤交换性Al^(3+),较对照降低3.04 cmol/kg (P <0.05)。在石灰岩土(pH 6.13)中,4种有机物料对土壤pH均有显著提高作用(P <0.05),其中黄腐酸钾的作用高于其它3种有机物料,高于对照0.98个单位(P <0.05);但4种有机物料对降低石灰岩土的土壤交换性Al^(3+)均无显著效果。【结论】有机物料对不同产量水平的山核桃林地土壤的培肥改良作用不同:有机物料在高产林地上具有养分供应的提升和协调的作用;有机物料在低产林地上具有显著提高土壤速效养分、提高土壤pH、降低酸性土壤中铝的生物毒害的作用。

【Objectives】The great differences in soil productivity and soil fertility are existed among the forest soils with low-yielding and high-yielding Carya cathayensis.Comparing the differences of organic materials on the improvement of soil acidity and fertility will provide a theoretical guidance for the effective application of organic materials.【Methods】Carya cathayensis forest lands originated from red soil(low-yielding)and limestone soil(high-yielding)were chosen for the two independent incubation experiments.Four kinds of organic materials,bio-organic fertilizer(BF),potassium humate(KH),bamboo-char(BC)and biogas residue(BR),were supplied into the soils by the rate of 1%accounting for total soil weights,and incubated at a constant temperature of 25℃.Soil samples were collected at 0,30,60,90 and 180 d to measure the soil pH,available N,available P,available K and available micronutrients of Fe,Mn,Cu and Zn,respectively.【Results】1)Red soil after incubation of 180 days,organic materials affected nutrient availabilities in different levels.Available N was only significantly increased in the BR treatment and was 52.85 mg/kg higher than control(P<0.05);all of four organic materials increased soil available P,and those in the BF and KH treatments were significantly higher than in the BC and BR treatments,and were 13.21 mg/kg and 12.07 mg/kg higher than the control(P<0.05),respectively.All the four organic materials significantly increased soil available K(P<0.05),and that in KH treatment was significantly higher than those in the others,and was 136.00 mg/kg higher than control.Only the KH demonstrated significant increase of soil available Fe and that was 71.59 mg/kg higher than the control(P<0.05),the BC significantly increased soil available Zn and that was 0.94 mg/kg higher than control,and no organic materials increased soil available Mn and Cu.2)In limestone soil after incubation of 180 days,four organic materials did not improve the soil available N,but significantly increased soil available P(P<0.05).The soil available P in the BF treatment was significantly higher than those in the other three ones(P<0.05),and was 4.67 mg/kg higher than control(P<0.05).The soil available K in the KH treatment was significantly higher than those in the other three ones(P<0.05),and was 94.00 mg/kg higher than control(P<0.05).Both the BF and the KH treatments significantly increased soil available Fe,and resulted in an increase of 190.61 mg/kg and 249.43 mg/kg than the control(P<0.05).The soil available Mn in the BF,KH and BC treatments were significantly increased by 135.74 mg/kg,155.96 mg/kg and 51.51 mg/kg(P<0.05),respectively.Soil available Cu in both the BF and the KH treatments were also significantly increased,and were 1.79 mg/kg and 2.99 mg/kg higher than the control.Available Zn was only significantly increased in the BR treatment,and was 3.23 mg/kg higher than the control(P<0.05).3)In red soil(pH 4.46),only BR increased soil pH,and reduced soil exchangeable Al3+by 3.04 cmol/kg than the control(P<0.05).By contrast,in limestone soil(pH 6.13),all the four organic materials significantly increased soil pH(P<0.05),but did not greatly affect the exchangeable Al3+content.