不同稳定性有机物料对砂姜黑土理化性质及玉米产量的影响

针对黄淮海平原广泛分布的砂姜黑土结构性差、有机质含量偏低的特征,通过中国科学院封丘农田生态系统国家试验站2年砂姜黑土不同外源有机物料施用处理盆栽试验共设8个处理,分别为空白(CK)、施秸秆(S)、施有机肥(M)、施1/2秸秆+1/2有机肥(SM)、施生物炭(C)、施1/2生物炭+1/2秸秆(CS)、施1/2生物炭+1/2有机肥(CM)和施1/3生物炭+1/3有机肥+1/3秸秆(CSM)],研究了等C、N输入下不同稳定性有机物料(生物炭、秸秆、有机肥)对砂姜黑土理化性质及玉米产量的影响。结果表明,与CK处理相比,施用外源有机物料能显著降低土壤容重19.60%~32.23%,增加饱和含水量7.91%~28.99%、田间持水量10.47%~30.76%,提高耕层土壤总孔隙度10.36%~28.21%,提升全量有机质11.00%~37.00%;并对活性有机质组分(低活性有机质、中活性有机质、高活性有机质)产生显著影响,其中高活性有机质增加幅度高达39.22%~83.83%。从有机物料的配比效果来看,CSM处理土壤容重最低,为1.28 g?cm?1,C、S处理土壤容重分别为1.30 g?cm?1、1.36 g?cm?1。CSM处理土壤总孔隙度最大,为58.53%;S、CS、SM处理次之,分别为55.62%、56.90%、54.38%;C、M处理最小,分别为53.18%、50.38%。CS、CM、CSM处理土壤总有机质含量较高,分别为30.76 g?kg?1、32.99 g?kg?1、31.45 g?kg?1;C、S处理相对较低,分别为25.36 g?kg?1、26.16 g?kg?1。CS、SM、CSM处理玉米产量最高,分别为463.67 g?盆?1、376.31 g?盆?1、471.77 g?盆?1,且差异性显著。可见不同稳定性有机物料施入能够改善土壤理化性质,提高玉米产量,生物炭配合秸秆、有机肥还田处理改良土壤及增产效果最佳。

Effects of different stable organic matters on physicochemical properties of lime concretion black soil and maize yield

With poor physical properties and low organic matter content, lime concretion black soil is one of the lowest productive soils and is widely distributed in the Huang-Huai-Hai Plain in China. Although the physical and chemical properties of lime concretion black soil influenced by exogenous organic matter have been widely reported, few studies have focused on the effects of synchronous application of organic materials with different stabilities in lime concretion black soil. Thus a two-year pot experiment was conducted at the State Experimental Station of Agro-Ecosystem in Fengqiu to evaluate the effects of organic materials with different stabilities (biochar, organic fertilizer and straw) on the physico-chemical properties of lime concretion black soil and maize yield. Eight treatments were designed based on applications of different organic materials with the same inputs of carbon and nitrogen, which were CK (no fertilizer), straw (S), organic manure (M), biochar (C), 1/2 straw + 1/2 organic manure (SM), 1/2 biochar + 1/2 straw (CS), 1/2 biochar + 1/2 organic manure (CM), and 1/3 biochar + 1/3 organic fertilizer + 1/3 straw (CSM). Compared with CK, the application of different organic materials decreased soil bulk density by 19.60%32.23% and increased saturated soil moisture, field capacity and total porosity by 7.91%28.99%, 10.47%30.76% and 10.36%28.21%, respectively. There were significant differences in total organic matter and labile organic matter contents of soil between CK and organic materials application treatments. The trends of increase in different components of organic matter were similar. On the other hand, the variation range of high labile organic matter was obviously greater than that of total organic matter. The high labile organic matter content increased by 39.22%8.83%, whereas that of total organic matter increased by 11.00%37.00% under organic materials treatments. Bulk density of CSM (1.28 gcm^-1) was lower than those of C (1.30 gcm^-1) and S (1.36 gcm^-1). Total porosity of CSM was highest (58.53%) among all treatments. Total porosity under CS, SM, S, C and M treatments was 56.90%, 54.38%, 55.62%, 53.18% and 50.38%, respectively. Total organic matter content of CS, CM, CSM, C and S was 30.76 gkg^-1, 32.99 gkg^-1, 31.45 gkg^-1, 25.36 gkg^-1 and 26.16 gkg^-1, respectively. Maize yield for different treatments were similar in trend to that of total organic matter content. Grain yield for CS, SM and CSM was respectively 463.67 gpot^-1, 376.31 gpot^-1 and 471.77 gpot^-1; higher than that of C, S and M. Overall, mixed application of biochar, straw and organic fertilizer was by far better than the application of sole organic material in terms of improving soil physico-chemical properties and maize yield.