吉林省西部草原生态地球化学评价

发布时间：2018-07-15 09:47

【摘要】：吉林省西部草原位于大兴安岭森林、科尔沁草原湿地、松辽平原黑土地三个生态系统的过渡带，草原类型主要为平原草甸草原草场类、平原草甸草场类、丘陵干草原草场类。吉林省西部草原不仅是吉林省重要的生态系统和生态屏障，同时也吉林省重要的农牧产品基地。近些年来，由于人为破坏和自然环境变化，吉林省西部草原退化较为严重，因此，研究草原区土壤中矿质营养元素、重金属元素的分布特征、牧草中元素的分布及其对土壤元素富集特征，对吉林省西部草原的保护和管理等有着十分重要的意义。本文通过吉林省西部草原区土壤、牧草样品的分析测定，研究了草原区土壤中矿质营养元素、重金属元素的分布与富集特征、土壤重金属形态分布特征、牧草营养元素的分布特征，研究了土壤-牧草间元素的相关性，对土壤肥力、土壤重金属污染水平、牧草质量等进行了评价。通过研究，得到如下认识： 1.吉林省西部草原表层土壤中Al2O3、TFe2O3、MgO、B、Mn、Co、Mo、Pb、Cu、Zn、As、Hg、Ni、Cr、Cd含量均低于全国土壤背景值，Na2O、K2O含量高于全国土壤背景值，土壤CaO、N、Cl空间含量差异较大，变异系数较高。表土中矿质营养元素含量分布多呈北高南低的趋势 2.相关性分析和因子分析结果表明，本区微量营养元素如Co、Zn、Cu、Mo、Mn和重金属元素Cr、Ni、As、Pb、Hg、（Cu）、（Zn）的主要来源为成土母质，营养元素N、P、K2O、CaO和重金属元素Cd含量受成土作用等影响较大，B、MgO的含量与土壤pH相关性较大，Cl、Na2O的含量影响着土壤电导率。 3.通过土壤元素表层与深层含量比值和土壤重金属元素富集因子，本区表层土壤富集N、P、Cl、Na2O、K2O等营养元素，对重金属元素无富集。 4.本区土壤有效Mn、有效Mo、有效Zn含量处于极低水平，有效Cu含量处于适中水平，有效B、有效Fe处于极高水平。土壤水解N、有效P、有效K、有效Zn、有效B含量受土壤pH值、土壤电导率和土壤有机碳含量影响较大。土壤中As、Zn、Cr、Pb主要是以残渣态形式存在于土壤中，而Hg、Cd主要是以活性态形式存在，，Hg、Cd的潜在生态风险相对较大。 5.采用层次分析法评价本区土壤肥力等级，结果表明丘陵干草原土壤肥力最高，平原草甸草原草场肥力次之，多为二等土壤，平原草甸草场土壤肥力最低。采用内梅罗指数法评价本区土壤重金属污染情况，本区大部分土壤重金属元素含量处于安全水平，只有查干花镇周围土壤重金属达轻度污染水平，重金属元素As、Cr、Hg、Pb、Ni、Zn含量都在此区域均有一定程度富集。 6、本区牧草中As、B、Ni、Na、Ca、Cr、Mn、Fe、Co、Cd、Pb、F、P含量差异较大，草中Na、P含量与土壤pH、有机碳含量和土壤电导率显著相关，其他元素与土壤pH、有机碳含量和土壤电导率显著相关性较差。参照NRC饲料微量元素推荐值，本区牧草缺乏Zn、Cu、P，Ni含量部分超标，牧草中K、Mg、Ca、Mn、Co、Mo能满足羊生长发育和正常代谢的需求。吉林省西部草原土壤肥力水平较低，营养元素的有效态含量处于极低水平，重金属元素含量虽处于安全水平，但Hg、Cd的潜在生态风险相对较大。草原牧草缺乏Zn、Cu、P、，牧草中K、Mg、Ca、Mn、Co、Mo含量水平能满足草原动物生长需要。
[Abstract]:The western steppe of Jilin Province is located in the transitional zone of three ecosystems in the forests of Daxinganling , Horqin steppe and Songliao Plain . The steppe type is mainly the grassland of the plain meadow , the meadow of the plain meadow and the grass field of the dry grassland . In recent years , the grassland degradation in the western Jilin Province is more serious . In recent years , the distribution of mineral nutrients , heavy metal elements and the enrichment of elements in the forage grass are of great significance to the conservation and management of the grassland in the western Jilin Province .

Based on the analysis and determination of soil and forage samples in the grassland areas in western Jilin Province , the distribution and enrichment characteristics of heavy metal elements , the distribution characteristics of heavy metals in soils and the distribution characteristics of nutrient elements in soils were studied . The correlation between soil - pasture elements was studied , and the soil fertility , soil heavy metal pollution level and forage quality were evaluated .

1 . The content of Al2O3 , TFe2O3 , MgO , B , Mn , Co , Mo , Pb , Cu , Zn , As , Hg , Ni , Cr and Cd in the surface soil of the western steppe of Jilin Province is lower than that of the national soil background .

2 . Correlation analysis and factor analysis showed that the main sources of trace elements such as Co , Zn , Cu , Mo , Mn and heavy metal elements Cr , Ni , As , Pb , Hg , ( Cu ) and ( Zn ) were the main sources of soil - forming mother matter , N , P , K2O , CaO and Cd content of heavy metal elements were influenced by soil - forming effects .

3 . The nutrient elements such as N , P , Cl , Na2O and K2O are enriched in the surface soil of the soil by the ratio of the surface layer and the deep content ratio of the soil element and the enrichment factor of the heavy metal elements in the soil , and the heavy metal elements are not enriched .

4 . The soil available Mn , effective Mo , effective Zn content in the region are at very low levels , the effective Cu content is at a moderate level , the effective B and the effective Fe are at very high levels . The soil hydrolysis N , the effective P , the effective K , the effective Zn , the effective B content are influenced by the soil pH value , the soil electrical conductivity and the soil organic carbon content . As Hg and Cd are mainly in the form of the active state , the potential ecological risk of Hg and Cd is relatively large .

5 . The level of soil fertility in the region was evaluated by using analytic hierarchy process . The results showed that the soil fertility of the grassland was the highest , the soil fertility of the meadow was the lowest in the plain meadow , and the soil fertility was the lowest in the plain meadow .

6 . The contents of As , B , Ni , Na , Ca , Cr , Mn , Fe , Co , Cd , Pb , F and P in the forage grass in this area were significantly different . The contents of Na and P in grass were significantly correlated with soil pH , organic carbon content and soil electrical conductivity .

In the western part of Jilin Province , the soil fertility level is low , the effective state content of the nutrient elements is at very low level , the content of heavy metal elements is at a safe level , but the potential ecological risk of Hg and Cd is relatively large . The content of K , Mg , Ca , Mn , Co and Mo in the forage grass can meet the growth needs of the prairie animal .
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S812;X826

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