武汉设施菜地土壤有机碳变化及其典型影响因素的研究
发布时间：2019-02-16 00:51
【摘要】：设施蔬菜产业为解决蔬菜供应的季节性问题,缓解我国城郊人多地少的矛盾,增加农民的收入等方面的贡献巨大。设施菜地土壤因长期处于“高温、高湿、频繁连作、连续大量施肥、无降水淋洗”等特殊环境条件下,其理化性质往往不同于露天自然条件下的土壤。土壤有机碳在全球碳循环中扮演重要角色,其积累转化过程对全球碳循环有直接影响。本文选取武汉城郊设施土壤为研究对象,采用野外实地取样分析与室内模拟实验相结合的方法,研究了设施土壤有机碳的组成、积累及垂直分布等变化规律,探讨了设施环境典型条件对设施土壤有机碳转化的影响及其作用大小。主要结果与进展如下:(1)设施菜地土壤TOC、DOC、MBC和ROOC的含量普遍高于露天菜地。其中土壤TOC、DOC和MBC含量在设施年限1~5年之间变化不大,在5~20年之间,随着设施年限的增加均逐渐增加。(2)“空心菜-大蒜”轮种模式下的土壤TOC含量比“空心菜-芹菜”轮种模式高出6.1%,而三个采样时间的MBC含量要分别高出13.5%、9.2%和37.2%,而DOC和ROOC受土壤轮作模式的影响较小。(3)与露天土壤相应土层相比,设施土壤TOC在40 cm以下土层变化不明显,MBC在60 cm后的土层变化不大,但可DOC和ROOC表现出明显的耕层积累和垂直下迁现象,在100 cm层次的含量仍高于露天土壤。(4)在4~25℃条件下,温度升高可增加设施土壤ROOC和MBC的含量,而降低土壤DOC含量;在pH在5.30~8.34的范围内,土壤酸化可降低其ROOC和MBC的含量,而提高其DOC含量;土壤盐化程度加重降低了设施土壤DOC、MBC和ROOC的含量。(5)温度升高、土壤pH越接近中性、土壤盐化程度加重,这些环境变化均使设施土壤有机碳碳矿化量降低,而使土壤胡敏酸碳与富里酸碳的比值增加。(6)不同外源性有机碳、外源性磷、温度、水分和土壤pH这5个因素中,温度和外源性有机碳种类及其交互作用对土壤有机碳转化的影响最大,而各影响因素对土壤腐殖质组分转化的影响在30天的培养时间内并不显著。
[Abstract]:The facility vegetable industry contributes a lot to solve the seasonal problem of vegetable supply, alleviate the contradiction of large number of people and less land in the suburbs of our country, and increase the income of farmers. The physical and chemical properties of vegetable soil are different from those in open air because of the special environmental conditions such as "high temperature, high humidity, frequent continuous cropping, continuous fertilization and no precipitation leaching" for a long time. Soil organic carbon plays an important role in the global carbon cycle, and its accumulation and transformation process has a direct impact on the global carbon cycle. In this paper, the composition, accumulation and vertical distribution of organic carbon in facility soil were studied by combining field sampling analysis with indoor simulation experiment. The effects of typical conditions of facility environment on organic carbon transformation of greenhouse soil were discussed. The main results and progress are as follows: (1) the contents of TOC,DOC,MBC and ROOC in vegetable soil are generally higher than those in open vegetable field. The contents of TOC,DOC and MBC in soil changed little between 1 ~ 5 years, and between 5 ~ 20 years. With the increase of facility life, the soil TOC content of the model was 6.1 higher than that of the model of "celery". (2) the content of soil TOC was higher than that of "celery" under the rotation pattern of "empty vegetable and garlic", and the content of soil TOC was much higher than that of the model of "celery". However, the MBC content of the three sampling times was higher than that of 13.5and 37.2percent, respectively, while DOC and ROOC were less affected by the soil rotation model. (3) compared with the corresponding soil layers in open-air soil, the content of DOC and ROOC in the three sampling periods were higher than those in the corresponding soil layers. The change of TOC in the soil layer below 40 cm was not obvious, but that in the soil layer after 60 cm of MBC was not obvious, but DOC and ROOC showed obvious accumulation of plough layer and vertical migration. The content of ROOC and MBC in the soil at 100 cm level was still higher than that in the open soil. (4) at 4 ~ 25 鈩，
本文编号：2423872
[Abstract]:The facility vegetable industry contributes a lot to solve the seasonal problem of vegetable supply, alleviate the contradiction of large number of people and less land in the suburbs of our country, and increase the income of farmers. The physical and chemical properties of vegetable soil are different from those in open air because of the special environmental conditions such as "high temperature, high humidity, frequent continuous cropping, continuous fertilization and no precipitation leaching" for a long time. Soil organic carbon plays an important role in the global carbon cycle, and its accumulation and transformation process has a direct impact on the global carbon cycle. In this paper, the composition, accumulation and vertical distribution of organic carbon in facility soil were studied by combining field sampling analysis with indoor simulation experiment. The effects of typical conditions of facility environment on organic carbon transformation of greenhouse soil were discussed. The main results and progress are as follows: (1) the contents of TOC,DOC,MBC and ROOC in vegetable soil are generally higher than those in open vegetable field. The contents of TOC,DOC and MBC in soil changed little between 1 ~ 5 years, and between 5 ~ 20 years. With the increase of facility life, the soil TOC content of the model was 6.1 higher than that of the model of "celery". (2) the content of soil TOC was higher than that of "celery" under the rotation pattern of "empty vegetable and garlic", and the content of soil TOC was much higher than that of the model of "celery". However, the MBC content of the three sampling times was higher than that of 13.5and 37.2percent, respectively, while DOC and ROOC were less affected by the soil rotation model. (3) compared with the corresponding soil layers in open-air soil, the content of DOC and ROOC in the three sampling periods were higher than those in the corresponding soil layers. The change of TOC in the soil layer below 40 cm was not obvious, but that in the soil layer after 60 cm of MBC was not obvious, but DOC and ROOC showed obvious accumulation of plough layer and vertical migration. The content of ROOC and MBC in the soil at 100 cm level was still higher than that in the open soil. (4) at 4 ~ 25 鈩，
本文编号：2423872
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