中国农田土壤有机碳时空分布规律及影响因素研究
发布时间：2018-08-04 20:03
【摘要】：土壤有机质是土壤肥力的核心,是土壤的重要组成部分,虽然农田土壤有机碳只占土壤有机质总重量的一部分,但是农田土壤有机碳在保持土壤肥力、环境保护、农业可持续发展等方面都有着重要的作用和意义。建国以来,我国共开展了3次大规模土壤普查与测试工作,第一次土壤普查工作始于1958年,是以土壤农业性状为基础,并提出全国第一个农业土壤分类系统。第二次土壤普查工作始于1979年,是以成土条件、成土过程及其属性为土壤分类依据,采用土类、亚类、土属、土种、变种5级分类。第三次土壤测试工作始于2005年,我国开展了以国家财政补贴的全国范围测土配方施肥项目,全国所有农业县(场、单位)的土肥部门在当地大田、菜田、果园采集了大量土壤样品进行检验,主要包括土壤有机质、全氮、有效磷、速效钾、pH等项目。在区域尺度下,影响农田土壤有机碳主导因素一般是区域微观因素,如地形地貌、耕作制度、成土母质、植被、海拔高度等。但是在宏观尺度上,很多微观因素可能不是影响农田土壤有机碳分布的主要因素。本文系统整理了第一次土壤普查、第二次土壤普查和全国测土配方施肥项目的基础数据集,研究了大尺度时间上、空间上农田土壤有机碳分布规律,探讨了自然因素(年平均温度、年平均降水量,经度、纬度、气候变化、海拔高度)、土壤自身性质(pH、土壤粘粒结构、阳离子代换量等)、人为因素(施化肥、粮食产量、人口总量、秸秆还田)等主要因素对农田土壤有机碳含量与分布的影响,以期为揭示农田土壤有机碳演变规律、为政府部门制定相关政策提供理论基础,主要结果与结论如下:1.按照经度每隔10°、纬度每隔5°,将全国划为37个板块,对每个板块内60多年的农田土壤有机碳变化情况进行了分析,结果显示:60年来,我国华北地区和中部地区农田土壤有机碳含量呈现增加的趋势,而我国东北地区农田土壤有机碳含量下降明显。2.第一次土壤普查、第二次土壤普查和测土配方施肥结果显示,宏观层面上,纬度和年平均温度对农田土壤有机碳的分布有着重要的影响,农田土壤有机碳含量随着纬度的升高和年平均温度的降低呈现出升高趋势,经度和年平均降水量对农田土壤有机碳有一定的影响;在我国的东部到东北地区、西部地区,农田土壤有机碳含量随年平均温度的降低呈现升高的趋势,在我国的北部地区,农田土壤有机碳含量随着年平均降水量的降低而呈现降低的趋势;农田土壤有机碳含量随着pH的升高呈现下降的趋势,随着海拔的升高呈现先升高后降低的抛物线走势,随着粉粒、粘粒含量的升高呈现升高的趋势。3.测土配方施肥结果显示,在年平均温度小于10℃的区域范围内,农田土壤有机碳含量与年平均温度的相关性好于与年平均降水量的相关性,在10℃-20℃时的区域范围内,农田土壤有机碳含量与年平均降水量的相关性好于与年平均温度的相关性,在大于20℃时的区域范围内,农田土壤有机碳含量与年平均降水量和年平均温度的相关性都很差。但是偏相关结果表明,在在10℃-20℃时的区域范围内,农田土壤有机碳含量虽然与年平均温度和年平均降水量都有显著的正相关,但是农田土壤有机碳含量与年平均降水量的相关性要大于与年平均温度的相关性,年平均降水量才是农田土壤有机碳分布的主导因素;在年平均降水量0-200 mm的区域范围内,农田土壤有机碳含量与年平均降水量有显著的相关性,而与年平均温度的相关性很差,年平均降水量起主要驱动作用,在200-400 mm、400-600 mm、600-800 mm的年平均降水量的区域范围内,农田土壤有机碳含量与年平均温度的相关性要好于与年平均降水量的相关性,年平均温度起主要驱动作用,尤其在400-800 mm的区域范围内的半湿润地区,农田土壤有机碳含量与年平均温度的呈现极显著的关系,相关系数R=0.7430,在年平均降水量大于800 mm的区域范围内,农田土壤有机碳含量与年平均温度和年平均降水量的相关性都很差。4.虽然秸秆还田量的数据不全面,但是本研究分析2004年-2011年机械化秸秆还田面积与农用秸秆粉碎还田机拥有量具有极显著的相关性。在宏观层面上,利用中国1990年-2011年的机械化秸秆还田机数量,推算出1990年-2011年秸秆还田面积,深入分析了秸秆还田面积与农田土壤有机碳含量的关系。结果显示,20年来,我国31个省区市中,有近50%的省份的农田土壤有机碳含量呈现增加的趋势,而东北地区农田土壤有机碳含量下降较为明显。宏观层面上,秸秆还田面积变化率与农田土壤有机碳变化率在0.05水平上具有显著相关性。全国2011年机械化秸秆还田面积的平均值是1990年的2.92倍,但与全国农作物播种面积相比,我国秸秆还田的面积比例很低,只占16.89%。在宏观层面上,气候条件是影响农田土壤有机碳分布的重要外因,农田土壤有机碳库不是一个孤立的生态系统,影响农田土壤有机碳库的自然因素和人为因素中的各种因素尽管彼此之间存在着密切联系,但是人为因素作为影响农田土壤碳库变化的能动性因素,在一定时期内可以超过自然因素成为影响区域农田土壤有机碳库变化的主导因素。本研究将进一步揭示农田土壤有机碳变化规律,阐明自然因素和人为因素对农田土壤有机碳的影响,为合理制定农田土壤管理政策、促进土壤碳固定提供科学依据。
[Abstract]:Soil organic matter is the core of soil fertility and an important part of soil. Although soil organic carbon in farmland is only part of the total weight of soil organic matter, soil organic carbon in farmland has important role and significance in maintaining soil fertility, environmental protection, and sustainable agricultural development. Since the founding of the people's Republic, China has carried out 3. The first Soil Census began in 1958. The first soil survey was based on soil agricultural properties, and the first agricultural soil classification system in China was put forward. The second Soil Census began in 1979. It was based on soil forming conditions, soil forming process and its genus as the basis for soil classification, and soil, subcategory, and soil genera. 5 grade classification of soil species and variety. The third soil testing work began in 2005. China carried out a national soil testing and fertilization project with national financial subsidies. The soil and fertilizer departments of all agricultural counties (fields and units) collected a large number of soil samples in the local fields, vegetable fields and orchards, including soil organic matter, total nitrogen and effective soil. Phosphorus, quick acting potassium, pH and other projects. Under regional scale, the main factors affecting soil organic carbon in farmland are regional microcosmic factors, such as topography, tillage system, soil parent material, vegetation, altitude and so on. But on the macro scale, many micro factors may not be the main factors that affect the distribution of organic carbon in farmland soil. This paper systematically collates the factors. The first soil survey, the second soil survey and the basic data set of the national soil testing formula fertilization project, studied the distribution of soil organic carbon in the large scale time, and discussed the natural factors (annual average temperature, annual mean precipitation, longitude, latitude, climate change, altitude), soil properties (pH, soil viscosity). The effects of human factors (fertilizer application, grain yield, total population, straw returning) on the soil organic carbon content and distribution of farmland soil, in order to reveal the law of soil organic carbon evolution in farmland, provide a theoretical basis for government departments to formulate relevant policies. The main results and conclusions are as follows: 1. according to the following: The degree of soil organic carbon change of farmland soil in each plate for more than 60 years was analyzed every 10 degrees and 5 degrees every 5 degrees. The results showed that the soil organic carbon content of farmland soil in North China and central region showed an increasing trend in the last 60 years, and the organic carbon content of farmland soil decreased obviously in Northeast China for 60 years. .2. first soil survey, second soil survey and soil testing formula fertilization results showed that latitude and annual average temperature had an important influence on the distribution of soil organic carbon in farmland. The content of soil organic carbon in farmland increased with the elevation of latitude and the decrease of annual average temperature, longitude and annual average precipitation. The organic carbon content of farmland soil has a certain influence. In the east to the northeast of China, the organic carbon content of farmland soil decreases with the decrease of annual average temperature in the western region. In the northern part of China, the organic carbon content of farmland soil decreases with the decrease of annual average precipitation, and the organic carbon in farmland soil. With the increase of pH, the content of the content increased with the increase of the elevation and then the decrease of the parabolic trend. With the grain and the increase of the clay content, the.3. soil formula fertilization results showed that the organic carbon content of farmland soil and the annual average temperature were in the area of the average annual temperature less than 10 degrees C. The correlation is better than the annual average precipitation. The correlation between the soil organic carbon content and annual average precipitation is better than the annual average temperature in the area range of 10 -20 C. The correlation of soil organic carbon content with annual mean precipitation and annual average temperature in the area over 20 degrees centigrade is very good. The correlation results show that the organic carbon content in farmland soil has significant positive correlation with annual mean temperature and annual mean precipitation at 10 -20 C, but the correlation between soil organic carbon content and annual average precipitation is higher than that of annual mean temperature. The dominant factor in the distribution of organic carbon in farmland soil; in the regional range of annual average precipitation of 0-200 mm, there is a significant correlation between the organic carbon content of farmland soil and the annual average precipitation, but the correlation with the annual average temperature is very poor. The annual mean precipitation has the main driving effect, the annual average precipitation of 200-400 mm, 400-600 mm and 600-800 mm. The correlation between soil organic carbon content and annual average temperature in farmland is better than that of annual mean precipitation. The annual mean temperature is the main driving force, especially in the semi humid area of 400-800 mm. The organic carbon content of farmland soil has a very significant relationship with the annual average temperature, and the correlation coefficient is R=. 0.7430, the correlation of soil organic carbon content with annual mean temperature and annual mean precipitation in the area of annual average precipitation greater than 800 mm is very poor.4. although the data of straw returning amount is not comprehensive. However, this study analyses the possession of Mechanized Straw Returning surface and agricultural straw comminution machine in the year of 2004 in -2011 At the macro level, using the number of Mechanized Straw Returning machines in China in 1990 -2011, the straw returning area in 1990 was calculated in the year of 1990. The relationship between the straw returning area and the soil organic carbon content of farmland was deeply analyzed. The results showed that in the 31 provinces and regions of China, there were nearly 50% of the farmland soil in the 20 years. Organic carbon content showed an increasing trend, and the decrease of organic carbon content in farmland soil in Northeast China was more obvious. On macro level, the change rate of straw returning area and the change rate of soil organic carbon in farmland had significant correlation with the 0.05 level. The average value of Mechanized Straw Returning to farmland in 2011 was 2.92 times that of 1990, but it was the same as that of the whole country. Compared with the crop sown area, the area ratio of straw returning in China is very low, only 16.89%. is on the macro level. Climate conditions are the important factors affecting the distribution of organic carbon in farmland soil. The soil organic carbon bank of farmland is not an isolated ecosystem, which affects the natural factors and human factors of soil organic carbon pool in farmland soil. Although there is a close relationship with each other, human factors as a dynamic factor affecting the change of soil carbon pool in farmland can exceed the natural factors in a certain period to be the dominant factor affecting the change of organic carbon pool in farmland soil. This study will further reveal the regularity of soil organic carbon change in farmland and clarify the natural causes. The effects of vegetation and anthropogenic factors on soil organic carbon in farmland provide scientific basis for rational formulation of farmland soil management policies and promotion of soil carbon fixation.
【学位授予单位】：吉林农业大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S153.6
本文编号：2164990
[Abstract]:Soil organic matter is the core of soil fertility and an important part of soil. Although soil organic carbon in farmland is only part of the total weight of soil organic matter, soil organic carbon in farmland has important role and significance in maintaining soil fertility, environmental protection, and sustainable agricultural development. Since the founding of the people's Republic, China has carried out 3. The first Soil Census began in 1958. The first soil survey was based on soil agricultural properties, and the first agricultural soil classification system in China was put forward. The second Soil Census began in 1979. It was based on soil forming conditions, soil forming process and its genus as the basis for soil classification, and soil, subcategory, and soil genera. 5 grade classification of soil species and variety. The third soil testing work began in 2005. China carried out a national soil testing and fertilization project with national financial subsidies. The soil and fertilizer departments of all agricultural counties (fields and units) collected a large number of soil samples in the local fields, vegetable fields and orchards, including soil organic matter, total nitrogen and effective soil. Phosphorus, quick acting potassium, pH and other projects. Under regional scale, the main factors affecting soil organic carbon in farmland are regional microcosmic factors, such as topography, tillage system, soil parent material, vegetation, altitude and so on. But on the macro scale, many micro factors may not be the main factors that affect the distribution of organic carbon in farmland soil. This paper systematically collates the factors. The first soil survey, the second soil survey and the basic data set of the national soil testing formula fertilization project, studied the distribution of soil organic carbon in the large scale time, and discussed the natural factors (annual average temperature, annual mean precipitation, longitude, latitude, climate change, altitude), soil properties (pH, soil viscosity). The effects of human factors (fertilizer application, grain yield, total population, straw returning) on the soil organic carbon content and distribution of farmland soil, in order to reveal the law of soil organic carbon evolution in farmland, provide a theoretical basis for government departments to formulate relevant policies. The main results and conclusions are as follows: 1. according to the following: The degree of soil organic carbon change of farmland soil in each plate for more than 60 years was analyzed every 10 degrees and 5 degrees every 5 degrees. The results showed that the soil organic carbon content of farmland soil in North China and central region showed an increasing trend in the last 60 years, and the organic carbon content of farmland soil decreased obviously in Northeast China for 60 years. .2. first soil survey, second soil survey and soil testing formula fertilization results showed that latitude and annual average temperature had an important influence on the distribution of soil organic carbon in farmland. The content of soil organic carbon in farmland increased with the elevation of latitude and the decrease of annual average temperature, longitude and annual average precipitation. The organic carbon content of farmland soil has a certain influence. In the east to the northeast of China, the organic carbon content of farmland soil decreases with the decrease of annual average temperature in the western region. In the northern part of China, the organic carbon content of farmland soil decreases with the decrease of annual average precipitation, and the organic carbon in farmland soil. With the increase of pH, the content of the content increased with the increase of the elevation and then the decrease of the parabolic trend. With the grain and the increase of the clay content, the.3. soil formula fertilization results showed that the organic carbon content of farmland soil and the annual average temperature were in the area of the average annual temperature less than 10 degrees C. The correlation is better than the annual average precipitation. The correlation between the soil organic carbon content and annual average precipitation is better than the annual average temperature in the area range of 10 -20 C. The correlation of soil organic carbon content with annual mean precipitation and annual average temperature in the area over 20 degrees centigrade is very good. The correlation results show that the organic carbon content in farmland soil has significant positive correlation with annual mean temperature and annual mean precipitation at 10 -20 C, but the correlation between soil organic carbon content and annual average precipitation is higher than that of annual mean temperature. The dominant factor in the distribution of organic carbon in farmland soil; in the regional range of annual average precipitation of 0-200 mm, there is a significant correlation between the organic carbon content of farmland soil and the annual average precipitation, but the correlation with the annual average temperature is very poor. The annual mean precipitation has the main driving effect, the annual average precipitation of 200-400 mm, 400-600 mm and 600-800 mm. The correlation between soil organic carbon content and annual average temperature in farmland is better than that of annual mean precipitation. The annual mean temperature is the main driving force, especially in the semi humid area of 400-800 mm. The organic carbon content of farmland soil has a very significant relationship with the annual average temperature, and the correlation coefficient is R=. 0.7430, the correlation of soil organic carbon content with annual mean temperature and annual mean precipitation in the area of annual average precipitation greater than 800 mm is very poor.4. although the data of straw returning amount is not comprehensive. However, this study analyses the possession of Mechanized Straw Returning surface and agricultural straw comminution machine in the year of 2004 in -2011 At the macro level, using the number of Mechanized Straw Returning machines in China in 1990 -2011, the straw returning area in 1990 was calculated in the year of 1990. The relationship between the straw returning area and the soil organic carbon content of farmland was deeply analyzed. The results showed that in the 31 provinces and regions of China, there were nearly 50% of the farmland soil in the 20 years. Organic carbon content showed an increasing trend, and the decrease of organic carbon content in farmland soil in Northeast China was more obvious. On macro level, the change rate of straw returning area and the change rate of soil organic carbon in farmland had significant correlation with the 0.05 level. The average value of Mechanized Straw Returning to farmland in 2011 was 2.92 times that of 1990, but it was the same as that of the whole country. Compared with the crop sown area, the area ratio of straw returning in China is very low, only 16.89%. is on the macro level. Climate conditions are the important factors affecting the distribution of organic carbon in farmland soil. The soil organic carbon bank of farmland is not an isolated ecosystem, which affects the natural factors and human factors of soil organic carbon pool in farmland soil. Although there is a close relationship with each other, human factors as a dynamic factor affecting the change of soil carbon pool in farmland can exceed the natural factors in a certain period to be the dominant factor affecting the change of organic carbon pool in farmland soil. This study will further reveal the regularity of soil organic carbon change in farmland and clarify the natural causes. The effects of vegetation and anthropogenic factors on soil organic carbon in farmland provide scientific basis for rational formulation of farmland soil management policies and promotion of soil carbon fixation.
【学位授予单位】：吉林农业大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S153.6
【参考文献】
相关期刊论文 前1条
1 张金屯;全球气候变化对自然土壤碳、氮循环的影响[J];地理科学;1998年05期
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