南方地区冷浸田土壤质量调查与评价指标体系研究

发布时间：2018-12-10 09:50

【摘要】：我国南方地区冷浸田面积大、分布广、产量低,冷浸田具有物理性质差、有机质积累多、还原性强、土壤温度低、有效养分缺乏、通透性差等一系列特点。本研究以我国南方地区7个省份冷浸田以及相应的非冷浸田为调查对象,调查冷浸田土壤理化性状和生物学性状,明确冷浸田的主要障碍因子,筛选冷浸田土壤质量评价指标,建立起土壤质量评价的最小数据集。研究结果对冷浸田土壤质量评价、土壤改良具有重要意义。主要研究结论如下:(1)冷浸田土壤有机质(44.04±1.52 g/kg)、全氮(2.27±0.08 g/kg)、C/N(11.34士0.26)均显著高于非冷浸田,分别较非冷浸田高26.1%、11.2%、12.3%,冷浸田土壤全磷、全钾、碱解氮、速效钾含量与非冷浸田差异不显著。冷浸田土壤速效磷(5.39±0.92 mg/kg)显著低于非冷浸田,较非冷浸田低84.6%。冷浸田土壤含水量、有效铁、有效锰、有效锌、Fe2+、Mn2+、还原性物质总量含量均显著高于非冷浸田,平均值分别为 45.13%、905.44 mg/kg、117.11 mg/kg、6.42 mg/kg、956.10 mg/kg、61.36 mg/kg、2.48 cmol/kg,分别较非冷浸田高 37.6%、91.5%、108.1%、17.0%、349.5%、143.1%、217.9%。(2)冷浸田土壤微生物生物量碳(228.24±69.37 mg/kg)、磷酸酶活性(95.31±11.62 mg/kg/h)均显著低于非冷浸田,分别较非冷浸田低43.8%、25.2%;冷浸田土壤过氧化氢酶活性显著高于非冷浸田,高出21.1%;蔗糖酶活性与非冷浸田相比无显著差异。(3)冷浸田土壤线虫数量为301.95条/100 g干土,显著低于非冷浸田(584.31±151.30条/100g干土)。冷浸田与非冷浸田土壤线虫群落组成以及营养结构相似,总体表现为植物寄生线虫食细菌线虫食真菌线虫捕食-杂食线虫。优势线虫属丝尾垫刃属(Filenchus)、潜根属(Hirschmanniella)以及常见属头叶属(Cephalobus)、滑刃属(Aphelenchoides)在我国南方水稻田广泛分布。冷浸田土壤线虫群落的多样性指数(H')和丰富度指数(SR)总体显著高于非冷浸田。(4)采用配对样本t检验和主成分分析方法,结果表明冷浸田土壤质量评价的最小数据集为全氮、速效磷、有效锰、Fe2+、pH、丰富度指数(SR)6个指标,冷浸田土壤质量指数显著低于非冷浸田。综上所述,冷浸田土壤养分含量不低,但土壤水分以及还原性物质过多,因此水利工程改良是冷浸田土壤改良的首要任务,另外耕作改良和施肥改良也是提高冷浸田产量的重要途径。
[Abstract]:The cold soaking field in southern China has a series of characteristics, such as large area, wide distribution, low yield, poor physical properties, accumulation of organic matter, strong reduction, low soil temperature, lack of available nutrients, poor permeability and so on. In this study, the soil physicochemical and biological characters of cold soaking field were investigated, the main obstacle factors of cold soaking field were determined, and the evaluation index of soil quality was screened. The minimum data set for soil quality evaluation was established. The results are of great significance for soil quality evaluation and soil improvement in cold soaking fields. The main results were as follows: (1) soil organic matter (44.04 卤1.52 g/kg), total nitrogen (2.27 卤0.08 g/kg), C / N (11.34 卤0.26) were significantly higher in cold soaking field than in non-cold soaking field. The soil contents of total phosphorus, total potassium, alkali-hydrolyzed nitrogen and available potassium in cold soaking field were not significantly different from those in non-cold soaking field, and the content of total phosphorus, total potassium, alkali-hydrolyzed nitrogen and available potassium in cold soaking field were higher than that in non-cold soaking field, respectively. Soil available phosphorus (5.39 卤0.92 mg/kg) in cold soaking field was significantly lower than that in non cold impregnated field and 84.6% lower than that in non cold impregnated field. The soil water content, available iron, available manganese, available zinc, Fe2, Mn2 and total content of reductive substances in cold-soaked field were significantly higher than those in non-cold-soaked field, the average values were 45.13 mg/kg,117.11 mg/kg,6.42 mg/kg, and 905.44 mg/kg,117.11 mg/kg,6.42 mg/kg, respectively. 956.10 mg/kg,61.36 mg/kg,2.48 cmol/kg, was 37. 6% higher than that in non-cold soaking fields, including 91. 5% 108. 1 and 17. 0% about 3. 34. 5% and 1. 43. 1% 217.9. (2) soil microbial biomass carbon (228.24 卤69.37 mg/kg) and phosphatase activity (95.31 卤11.62 mg/kg/h) were significantly lower than those in non-cold soaking field (43.8g / 25.2, respectively); (2) soil microbial biomass C (228.24 卤69.37 mg/kg) and phosphatase activity (95.31 卤11.62 mg/kg/h) were significantly lower than those in non-cold soaking field (P < 0.05). The activity of catalase in cold soaking field was significantly higher than that in non cold soaking field and was 21. 1% higher than that in non-cold soaking field. (3) the number of nematode in soil in cold soaking field was 301.95 / 100g dry soil, which was significantly lower than that in non-cold soaking field (584.31 卤151.30 dry soil). The community composition and nutritional structure of soil nematodes in cold immersion field and non cold impregnated field were similar, and the general characteristics were plant parasitic nematode, bacterial nematode, nematode eating fungus nematode predation and omnivorous nematode. Dominant nematodes are widely distributed in rice fields in southern China, including (Filenchus), (Hirschmanniella), and (Cephalobus), (Aphelenchoides). The diversity index (H') and richness index (SR) of soil nematode community in cold soaking field were significantly higher than those in non cold impregnated field. (4) paired sample t test and principal component analysis were used. The results showed that the minimum data sets of soil quality evaluation in cold soaking field were total nitrogen, available phosphorus, available manganese, Fe2, pH, richness index (SR), and the soil quality index of cold soaking field was significantly lower than that of non cold soaking field. To sum up, the soil nutrient content is not low, but the soil moisture and reducing material are too much, so water conservancy engineering improvement is the primary task of soil improvement in cold soaking field. In addition, tillage improvement and fertilization improvement are also important ways to increase yield of cold soaking field.
【学位授予单位】：南京农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S159.2

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