神农架不同海拔山地土壤中磷素赋存形态及其环境意义
发布时间：2018-09-11 15:19
【摘要】：磷是植物的必需营养元素,生态系统中磷的生物有效性取决于磷含量和形态。无机磷可以直接被植物和微生物利用,因而受到较多关注,而对有机磷的研究关注较少。作为环境中磷库重要组分的有机磷,人们对其土壤化学行为和植物营养贡献至今仍然理解不够;山地土壤受人为扰动小,水热条件变化规律性强,为探讨自然环境中磷形态的转化特征及周转过程提供了条件。因此,本研究就不同海拔高度的土壤在不同母质、不同植被不同土壤类型以及各种影响因子的作用下,土壤中磷和有机磷的分布、形态及其演变过程开展研究。取得了以下主要结果:(1)土壤样品采自湖北省神农架林区不同海拔高度(560 m、834 m、1200 m、1552 m、1750 m、2115 m、2425 m、2687 m和3093 m)的A、B层土壤,分为黄棕壤、山地黄棕壤、山地棕壤、山地暗棕壤、山地棕色针叶林土。土壤母质以页岩砂页岩为主,海拔高处以辉绿岩为主,植被主要是阔叶林、落叶阔叶林、针阔混交林等,土壤湿度随着海拔的升高逐渐先升高再减少的趋势。气温随海拔的升高而降低。土壤的粘土矿物以2:1型层状矿物为主(水云母和1.4 nm矿物含量占85%以上),1:1型高岭石含量很少,说明神农架垂直土壤风化作用较弱;随着海拔的升高1.4 nm矿物含量先减少后增多,水云母的含量先增多后减少,表明该区土壤中2:1型矿物的淋溶脱钾和层间羟基铝化作用相应地先减弱后增强。A、B两层土壤之间的差异性不明显,土壤呈酸性,p H呈先增大后减小趋势,A层土壤中的有机质含量明显高于B层。不同海拔高度的中的土壤铁铝氧化物差异显著,随着海拔的升高,非晶形铁氧化物和活化度都随着海拔的增高明显增大。(2)土壤全磷(TP)含量随海拔呈上升趋势,说明随着海拔升高,P周转慢,淋失少,且A层土壤总磷高于B层,随着土壤磷的再分配和淋洗的流失,土壤全磷是随着土壤深度的变化逐渐减少,说明表层土壤受植被影响富集磷的能力更强;而在黄棕壤海拔834 m处所有的各形态磷普遍偏低,可能受地形影响造成植被固磷能力下降所致。除山地棕色针叶林土(海拔3093 m)外,土壤总磷含量变化同土壤表层有机质含量变化相一致,这也表明山地土壤中P与有机质密切相关。(3)运用连续提取方法把土壤磷分为树脂磷(resin-P)、Na HCO3提取态有机磷和无机磷(Na HCO3-Po、Na HCO3-Pi)、Na OH提取态有机磷和无机磷(Na OH-Po、Na OH-Pi)、D.HCl、浓盐酸提取态有机磷和无机磷(Conc.Pi、Conc.Po)和残渣态磷(resual-P),不同形态的磷含含量随着海拔的变化差异性明显。供试土壤中活性磷(resin-P+Na HCO3-P)占全磷6-26%,随海拔变化呈减小趋势,表明在长期的成土过程中土壤物质不断释放磷进行补充;土壤Na OH-P(即中稳态有效磷)也是土壤磷的主要存在形态,占全磷含量的24%-57%左右,随着海拔的升高Na OH-P含量呈上升的趋势。浓盐酸提取态磷(Conc.P即闭蓄态磷)占总磷含量10.8-39.5%,在土壤中含量也比较高,一般认为是和土壤风化、发育的层次有关;残渣磷(resual-P)含量变化不大,占全磷范围在8.5-22%。随海拔升高,有机磷占土壤总磷从44.8-70%变化,说明有机磷是所有供试土壤中最主要的磷库,随海拔的变化趋势不是很明显;Na HCO3-Po在有机磷中的百分含量均随着土壤风化度的增大而增多,因此,在低海拔处土壤高温多雨,干湿季节明显,风化淋溶作用强烈,活性磷组分Na HCO3-Po组分含量比较高。有机磷库中含量最多的是中稳定态有机磷(即Na OH-Po),占有机磷的40.4-77.4%,远远大于无机磷的含量。我们认为中稳定态有机磷主要是与铁铝矿物结合形态的有机磷,XRD衍射鉴定表明中稳定态磷部分为与针铁矿结合形式存在。(4)土壤母质、气候、植被、温度和p H等因素的不同所导致土壤有机磷呈不同变化趋势。土壤活性磷(resin-P+Na HCO3-Pi)含量随着海拔的升高含量升高,这同土壤有机质含量的增多有着密切的联系。土壤中Na HCO3-Po、Na OH-Po与土壤中有机质含量、游离氧化铁铝呈极显著正相关性,表明铁铝氧化物在稳定土壤有机磷库中起重要作用。以上结果为阐明山地土壤磷素,尤其是其中有机磷的赋存形态、演化及其地球化学循环过程提供了科学依据。
[Abstract]:Phosphorus is an essential nutrient element for plants, and the bioavailability of phosphorus in the ecosystem depends on the content and form of phosphorus. Inorganic phosphorus can be used directly by plants and microorganisms, so much attention has been paid to it, but less attention has been paid to the study of organic phosphorus. As an important component of phosphorus pool in the environment, people pay attention to its soil chemical behavior and plant camp. Up to now, the nutrient contribution is still poorly understood; the mountain soils are little disturbed by human activities, and the water and heat conditions change regularly, which provides the conditions for studying the transformation characteristics and turnover process of phosphorus forms in the natural environment. The distribution, morphology and evolution of phosphorus and organic phosphorus in soils were studied. The main results were as follows: (1) Soil samples were collected from different altitudes (560 m, 834 m, 1200 m, 1552 m, 1750 m, 2115 m, 2425 m, 2687 m and 3093 m) in Shennongjia forest region of Hubei Province. The A and B layers of soils were divided into yellow brown soil, mountain yellow brown soil, mountain brown soil, mountain brown soil, and mountain brown soil. Dark brown soil, mountain brown coniferous forest soil. Soil parent material is mainly shale sand shale, diabase at high altitude. Vegetation is mainly broadleaf forest, deciduous broad-leaved forest, coniferous and broad-leaved mixed forest. Soil moisture increases first and then decreases with elevation. Air temperature decreases with elevation. Clay minerals in soil are 2:1 type. Layered minerals were dominant (hydromica and 1.4 nm minerals accounted for more than 85%), and the content of 1:1 kaolinite was small, indicating that the vertical soil weathering in Shennongjia was weak; with the elevation increasing, the mineral content of 1.4 nm first decreased and then increased, and the content of hydromica first increased and then decreased, indicating that the leaching of 2:1 type minerals and the interlayer hydroxyaluminium in the soil of this area were weaker. The difference between the two layers of soil A and B was not obvious, the soil was acidic, and the content of organic matter in the A layer was higher than that in the B layer. (2) Total phosphorus (TP) content in soil increased with altitude, indicating that with altitude increasing, P turnover was slow and leaching was less, and total phosphorus in layer A was higher than that in layer B. With the redistribution and leaching of soil phosphorus, total phosphorus in soil decreased gradually with the change of soil depth, indicating that topsoil was enriched by vegetation. In addition to the mountain brown coniferous forest soil (altitude 3093 m), the change of soil total phosphorus content was consistent with the change of soil surface organic matter content, which also indicated that P and organic matter were dense in the mountain soil. (3) Soil phosphorus was classified into resin-P, Na HCO3-extracted organic phosphorus and inorganic phosphorus (Na HCO3-Po, Na HCO3-Pi), Na OH-extracted organic phosphorus and inorganic phosphorus (Na OH-Po, Na OH-Pi), D.HCl, concentrated hydrochloric acid-extracted organic phosphorus and inorganic phosphorus (Conc.Pi, Conc.Po) and residual phosphorus (resual-P). The content of reactive phosphorus (resin-P+Na HCO3-P) in the tested soils accounted for 6-26% of total phosphorus, and decreased with the change of altitude, indicating that phosphorus was continuously released during the long-term soil-forming process to supplement; Na OH-P (i.e. moderately stable available phosphorus) was also the main form of soil phosphorus, accounting for 24% of total phosphorus content. Concentrated hydrochloric acid extractable phosphorus (Conc.P) accounted for 10.8-39.5% of total phosphorus, and its content in soil was also relatively high, generally believed to be related to soil weathering and development level; residual phosphorus (resual-P) content changed little, accounting for 8.5-22% of total phosphorus. The percentage of organic phosphorus in soil varied from 44.8% to 70%, indicating that organic phosphorus was the most important phosphorus pool in all tested soils, and the trend of change was not obvious with altitude. The percentage of Na HCO3-Po in organic phosphorus increased with the increase of soil weathering degree. Therefore, the soil at low altitude was high temperature and rainy, and in dry and wet seasons was obvious. The content of Na HCO3-Po in the organic phosphorus pool is the highest, which is 40.4-77.4% of the organic phosphorus, much higher than that of inorganic phosphorus. The content of soil organic phosphorus (resin-P+Na HCO3-Pi) increased with the increase of altitude, which was closely related to the increase of soil organic matter content. Po, Na OH-Po are positively correlated with soil organic matter content and free iron and aluminum oxide, indicating that iron and aluminum oxides play an important role in stabilizing soil organic phosphorus pool.
【学位授予单位】：华中农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S153.6
本文编号：2237069
[Abstract]:Phosphorus is an essential nutrient element for plants, and the bioavailability of phosphorus in the ecosystem depends on the content and form of phosphorus. Inorganic phosphorus can be used directly by plants and microorganisms, so much attention has been paid to it, but less attention has been paid to the study of organic phosphorus. As an important component of phosphorus pool in the environment, people pay attention to its soil chemical behavior and plant camp. Up to now, the nutrient contribution is still poorly understood; the mountain soils are little disturbed by human activities, and the water and heat conditions change regularly, which provides the conditions for studying the transformation characteristics and turnover process of phosphorus forms in the natural environment. The distribution, morphology and evolution of phosphorus and organic phosphorus in soils were studied. The main results were as follows: (1) Soil samples were collected from different altitudes (560 m, 834 m, 1200 m, 1552 m, 1750 m, 2115 m, 2425 m, 2687 m and 3093 m) in Shennongjia forest region of Hubei Province. The A and B layers of soils were divided into yellow brown soil, mountain yellow brown soil, mountain brown soil, mountain brown soil, and mountain brown soil. Dark brown soil, mountain brown coniferous forest soil. Soil parent material is mainly shale sand shale, diabase at high altitude. Vegetation is mainly broadleaf forest, deciduous broad-leaved forest, coniferous and broad-leaved mixed forest. Soil moisture increases first and then decreases with elevation. Air temperature decreases with elevation. Clay minerals in soil are 2:1 type. Layered minerals were dominant (hydromica and 1.4 nm minerals accounted for more than 85%), and the content of 1:1 kaolinite was small, indicating that the vertical soil weathering in Shennongjia was weak; with the elevation increasing, the mineral content of 1.4 nm first decreased and then increased, and the content of hydromica first increased and then decreased, indicating that the leaching of 2:1 type minerals and the interlayer hydroxyaluminium in the soil of this area were weaker. The difference between the two layers of soil A and B was not obvious, the soil was acidic, and the content of organic matter in the A layer was higher than that in the B layer. (2) Total phosphorus (TP) content in soil increased with altitude, indicating that with altitude increasing, P turnover was slow and leaching was less, and total phosphorus in layer A was higher than that in layer B. With the redistribution and leaching of soil phosphorus, total phosphorus in soil decreased gradually with the change of soil depth, indicating that topsoil was enriched by vegetation. In addition to the mountain brown coniferous forest soil (altitude 3093 m), the change of soil total phosphorus content was consistent with the change of soil surface organic matter content, which also indicated that P and organic matter were dense in the mountain soil. (3) Soil phosphorus was classified into resin-P, Na HCO3-extracted organic phosphorus and inorganic phosphorus (Na HCO3-Po, Na HCO3-Pi), Na OH-extracted organic phosphorus and inorganic phosphorus (Na OH-Po, Na OH-Pi), D.HCl, concentrated hydrochloric acid-extracted organic phosphorus and inorganic phosphorus (Conc.Pi, Conc.Po) and residual phosphorus (resual-P). The content of reactive phosphorus (resin-P+Na HCO3-P) in the tested soils accounted for 6-26% of total phosphorus, and decreased with the change of altitude, indicating that phosphorus was continuously released during the long-term soil-forming process to supplement; Na OH-P (i.e. moderately stable available phosphorus) was also the main form of soil phosphorus, accounting for 24% of total phosphorus content. Concentrated hydrochloric acid extractable phosphorus (Conc.P) accounted for 10.8-39.5% of total phosphorus, and its content in soil was also relatively high, generally believed to be related to soil weathering and development level; residual phosphorus (resual-P) content changed little, accounting for 8.5-22% of total phosphorus. The percentage of organic phosphorus in soil varied from 44.8% to 70%, indicating that organic phosphorus was the most important phosphorus pool in all tested soils, and the trend of change was not obvious with altitude. The percentage of Na HCO3-Po in organic phosphorus increased with the increase of soil weathering degree. Therefore, the soil at low altitude was high temperature and rainy, and in dry and wet seasons was obvious. The content of Na HCO3-Po in the organic phosphorus pool is the highest, which is 40.4-77.4% of the organic phosphorus, much higher than that of inorganic phosphorus. The content of soil organic phosphorus (resin-P+Na HCO3-Pi) increased with the increase of altitude, which was closely related to the increase of soil organic matter content. Po, Na OH-Po are positively correlated with soil organic matter content and free iron and aluminum oxide, indicating that iron and aluminum oxides play an important role in stabilizing soil organic phosphorus pool.
【学位授予单位】：华中农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S153.6
【参考文献】
相关期刊论文 前5条
1 成瑞喜;神农架自然保护区土壤的研究——Ⅱ.土壤腐殖质性质[J];华中农业大学学报;1989年03期
2 来璐,郝明德,彭令发;土壤磷素研究进展[J];水土保持研究;2003年01期
3 成瑞喜,李卫东,艾云祥;神农架垂直带土壤养分状况及林木立地条件[J];土壤通报;1993年01期
4 胡佩,周顺桂,刘德辉;土壤磷素分级方法研究评述[J];土壤通报;2003年03期
5 蒋柏藩,顾益初;石灰性土壤无机磷分级体系的研究[J];中国农业科学;1989年03期
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