农业生产碳足迹及氮肥去向的计量研究
发布时间：2018-09-08 09:41
【摘要】：自工业革命以来,人类活动导致的全球温室气体排放快速增长,其中二氧化碳(CO_2)排放的增加主要来源于化石燃料燃烧和土地利用变化,而甲烷和氧化亚氮排放主要来自农业。农业贡献了中国人为温室气体排放总量的11%,分别占人为源甲烷(CH_4)和氧化亚氮(N_2O)排放的52%和84%。农业缓解全球温室气体排放的重大科技减排潜力在于改善作物生产田间管理。而基于生命周期分析法的作物生产碳足迹计量可以帮助识别农业温室气体减排的关键技术和措施。本论文通过实地农场调查、文献收集获取数据,采用生命周期分析法,主要研究内容:(1)量化中国农业生产(粮食作物、蔬菜和水果)碳足迹及其构成;(2)分析比较不同经营规模、不同管理模式和不同环境条件下农业生产碳足迹的差异;(3)氮肥施用是导致农业生产高排放的主要原因,对氮肥的去向与利用率变化进行了研究分析,以构建用以系统评估农业生产碳足迹的方法学体系,提出农业温室气体减排的关键途径和技术选择,为农业生产可持续性管理和食物低碳消费提供科学依据和政策建议。得到的主要结果如下:1.量化了中国主要粮食作物生产的碳足迹,识别农业温室气体减排的关键途径本研究对中国东部代表性地区进行了实地农户问卷调查,获取粮食作物生产和管理相关数据,构成碳足迹评价数据库。采用生命周期评价方法,评估水稻、小麦和玉米粮食作物生产的碳足迹。结果表明,水稻、小麦和玉米的单位面积碳足迹(土地利用碳足迹)分别为6.0±0.1、3.0±0.2和2.3±0.1 t CO_2-eq ha~(-1),而单位产量碳足迹(产品碳足迹)分别为0.80±0.02、0.66±0.03和0.33±0.02 kg CO_2-eq kg~(-1)。其中,氮肥和农用机械分别贡献了总碳足迹的44%-79%和8%~(-1)5%。水稻生产总排放中,灌溉用电排放和稻田甲烷直接排放分别占19%和25%。但在小麦和玉米生产的碳足迹中,灌溉只占了2%-3%。而且,在不同气候地区间小麦和玉米碳足迹存在显著差异,主要是由于作物管理过程中氮肥和农业机械投入的差异所导致。研究还发现,农户承包管理的农田面积大小对作物生产碳足迹也有影响。相对于承包农田面积较小(0.5 ha)的生产条件,农户承包农田面积较大(0.5ha)时小麦和玉米碳足迹减少了22%-28%,这主要归因于农田管理效率的提高。研究也表明,我国粮食作物生产碳足迹高于西方国家,具有高碳排放特征,主要是由于氮肥的不合理施用,因而减少氮肥施用提高氮肥利用效率是中国农业粮食生产温室气体减排的关键途径;2.调查了南京市周边蔬菜生产,初步表征了大棚蔬菜生产的碳足迹,揭示蔬菜碳足迹与其营养价值及销售收益间存在冲突矛盾对南京市周边大棚蔬菜基地进行农户调查,访问获取了小青菜、苋菜、空心菜、番茄、黄瓜和土豆的生产管理调查资料,建成了蔬菜生产碳足迹数据库。采用同上的计量方法,结果表明,大棚蔬菜生产的土地利用碳足迹在0.7~(-1)0.4 tCO_2-eq ha~(-1)之间,且不同蔬菜种类间没有差异。但是,小青菜和苋菜的单位产量(产品)碳足迹(分别为0.34 kg CO_2-eq kg~(-1)和0.38 kg CO_2-eq kg~(-1))显著高于其它蔬菜种类(0.07-0.17 kg CO_2-eq kg~(-1));且小青菜和苋菜生产的单位收益碳排放也较高(分别为1.95kg CO_2-eq USD~(-1)和1.82 kg CO_2-eq USD~(-1))。然而,相比小青菜、番茄、黄瓜和土豆,空心菜和苋菜(分别为0.12kg CO_2-eq ANV~(-1)和0.36kg CO_2-eq ANV~(-1))的单位营养价值碳排放较低。化肥投入对碳足迹的贡献最大,占蔬菜生产总排放的55%-82%。其次为有机肥和灌溉,分别占总排放的2%-21%和1%-26%,不同蔬菜类型间差异较大;而农机、农膜和农药对碳足迹贡献最小,分别占总排放的5%、5%和2%。因此,减少化肥施用和增施有机肥可能是蔬菜生产实现减排的重要措施。不过,鼓励农北温室气体减排的同时,如何平衡人们的营养需求和农民的经济利益仍然是一个巨大的挑战。3.调查评价了中国主要水果生产的碳足迹,明确了水果生产在土地利用碳足迹与水果产品碳足迹间的反差,提出果园施肥管理是减排的重要途径分别在陕西、福建、湖北、河北和沪宁地区选择代表性果园实地调查了苹果、香蕉、柑橘、梨和桃等中国主要水果生产,按水果生产周期评价了水果生产的碳足迹。结果表明,在所有被调查的果园中,单位面积碳足迹(土地利用碳足迹)的范围从2.9 t CO_2-eq ha~(-1)到12.8t CO_2-eq ha~(-1),而单位产量碳足迹(水果产品碳足迹)范围从0.07 kg CO_2-eq kg~(-1)到0.7kg CO_2-eq kg~(-1)。这里,水果生产的土地利用碳足迹显著高于粮食作物,但水果产品碳足迹又显著低于粮食作物。柑橘和梨的产品碳足迹(分别为0.14和0.18 kg CO_2-eq kg~(-1))显著低于苹果、香蕉和桃(分别为0.24、0.27和0.37 kg CO_2-eq kg~(-1))。然而,从不同水果的营养价值来看,柑橘的单位营养价值碳排放强度(平均0.5 kg CO_2-eq g~(-1) Vc)显著低于其他水果(3.0-5.9kg CO_2-eq g~(-1) Vc)。此外,从果农可以获得的经济效益来看,柑橘和梨的单位收益碳排放强度(分别为1.20和1.01 kg CO_2-eq USD~(-1))显著高于苹果、香蕉和桃(0.87-0.39 kg CO_2-eq USD~(-1))。在果园的管理活动中,化学氮肥是最重要的贡献者,占温室气体排放总量的47%-75%。本研究也发现,在氮肥高效管理下,水果碳足迹降低且产量提高。适当增施有机肥和提高氮肥利用率是水果生产的重要减排途径。我们的研究建议鼓励低碳水果消费,而服务于减排的同时,如何权衡人们对营养的需要和果农的经济利益是重要的政策考量。4.量化了土地管理机制和不同农田管理模式对农业生产碳足迹的影响幅度,指出发展规模经营和集约化管理可以提高农业生产效率,具有巨大的减排潜力选择了鄱阳湖周边地区不同经营规模的农户(大户,3.3ha以上;小户,3.3 ha以下),详细调查了水稻生产和管理情况,分析比较了不同经营规模下水稻生产(早稻、晚稻和单季稻)的碳足迹。在调查的农户生产中,早稻碳足迹最低,单季稻次之而晚稻最高(单位面积碳足迹和单位产量碳足迹分别是:早稻,4.54±0.44t CO_2-eq ha~(-1)和0.62±0.1 kg CO_2-eq kg~(-1);单季稻,6.84±0.79t CO_2-eq ha~(-1)和0.80±0.13 kg CO_2-eq kg~(-1)和晚稻,8.72±0.54t CO_2-eq ha~(-1)和1.1±0.17 kg CO_2-eq kg~(-1))。氮肥施用和稻田甲烷排放是水稻生产碳排放的最大贡献者,分别占总碳足迹的33%和57%。比较而言,大户双季稻产品碳足迹(0.86±0.11kg CO_2-eq kg~(-1))比小户(1.14±0.25kg CO_2-eq kg~(-1))减少了25%,主要是由于规模化种植模式下氮肥利用率得到提高和良好水分管理下甲烷排放的降低。因此,优化农田管理方式和发展规模化种植模式是减少中国农业温室气体排放的重要策略。而对江苏典型地区土地流转农场的实地调查计量表明,农户分散经营管理模式(散户)、集约型生产模式(无公害农场)和有机生产模式(有机农场)三种管理模式下水稻碳足迹存在显著差异。散户经营管理下水稻产品碳足迹(0.80 kg CO_2-eq kg~(-1))显著高于有机农场(0.56 kg CO_2-eq kg~(-1))和集约型农场管理模式(0.50 kg CO_2-eq kg~(-1))。其差异主要表现在肥料和农药投入及灌溉管理活动的不同,在集约化和有机生产管理模式下这三项投入的碳成本显著减少。而散户经营管理下灌溉用电导致的排放和稻田甲烷直接排放显著高于集约型和有机模式。有机生产管理模式中由于有机肥替代了化肥,生物农药替代了化学农药,这些有机生产资料的碳成本较低。上述结果说明,集约型农场管理模式是一种既低碳又高产的农业生产方式,当前仍具有显著的减排潜力,而改善散户经营管理可能是中国农业温室气体减排的普遍任务。5.对全球研究文献的统计和计量,揭示了提高氮肥利用率的重要途径是提高土壤中残留氮的作物吸收利用,为指导氮肥合理施用和温室气体减排提出了重要方向氮肥是农业生产不可或缺的外部投入,但氮肥利用率的问题一直困扰着肥料施用和环境管理。收集了全球范围内氮肥田间试验的已发表英文文献,获取了肥料、土壤、作物相关数据和15N标记丰度数据,建成数据库,分析评估肥料氮去向和作物吸收氮的来源,以探讨提高氮肥利用率的农田管理措施。结果表明,作物氮来源于肥料氮的比例平均不到一半,而大部分氮是直接或间接来源于土壤氮。施肥后的当季收获作物氮中来源于肥料氮的比例,玉米、水稻和其它小粒谷类作物(包括大麦、小麦、小米、燕麦和高粱)平均分别为41%、32%和37%。相比无机肥料,有机肥料(粪肥、绿肥、堆肥等)在当季作物的氮回收率平均为29%,但在后季作物中的氮回收率还可达到10%。可以认为,作物中大多数非肥料氮来自土壤和作物残留氮的周转,但后季作物对无机肥料氮总回收率仅占5%。因此,以往考虑提高肥料氮利用率时,可能忽视了作物氮最重要的来源—土壤氮。关注提高土壤中残留肥料氮的作物吸收利用和合理施用有机氮肥可能是提高氮肥利用率的重要途径。本论文量化了中国主要种植业生产(包括粮食作物、大棚蔬菜和水果)的碳足迹,并对不同环境条件、不同经营规模和不同管理模式下作物生产碳足迹进行比较,探明了中国农业生产碳足迹特征及其不同产业的碳排放差异,也为政策制定者提供低碳生产和低碳消费的科学依据。同时,对农业系统中氮肥去向与作物氮素来源的研究提示了对土壤残留氮素的利用是提高氮肥利用率的重要途径,并支持了有机肥对于提高氮肥利用率并降低温室气体排放的重要意义。本研究也提出了碳足迹在评价农业生产环境影响中的问题和挑战,例如如何权衡土地利用碳强度和农产品碳强度(反之是碳排放的生产效益),特别是考虑农产品的营养价值和农民的销售收益。这些问题,可能对于国家正在实施的生态文明建设具有重要的科学价值和政策意义,值得进一步研究。
[Abstract]:Since the Industrial Revolution, human activities have led to a rapid increase in global greenhouse gas emissions. Increases in carbon dioxide (CO 2) emissions are mainly due to fossil fuel combustion and land use change, while methane and nitrous oxide emissions are mainly from agriculture. Agriculture contributes 11% of the total anthropogenic greenhouse gas emissions in China, accounting for anthropogenic sources, respectively. Methane (CH_4) and nitrous oxide (N_2O) emissions account for 52% and 84%. Improving crop production management is a major scientific and technological potential for mitigating global greenhouse gas emissions in agriculture. Field farm survey, literature collection and data acquisition, using life cycle analysis, the main research contents: (1) quantify the carbon footprint and its composition of China's agricultural production (grain crops, vegetables and fruits); (2) analyze and compare the differences of carbon footprint of agricultural production under different management scale, different management modes and different environmental conditions; (3) nitrogen fertilizer application is the cause The main reasons for the high emission of agricultural production were studied and analyzed. A methodological system for systematically assessing the carbon footprint of agricultural production was established. The key ways and technical choices for reducing greenhouse gas emissions in agriculture were put forward, which provided scientific basis for sustainable agricultural production management and low carbon consumption of food. The main results are as follows: 1. Quantifying the carbon footprint of major grain crops in China and identifying the key ways to reduce greenhouse gas emissions in agriculture The results showed t ha t the carbon footprint per unit area (land use carbon footprint) of rice, wheat and maize were 6.0 (+0.1), 3.0 (+0.2) and 2.3 (+0.1) t CO_2-eq ha-1, respectively, while the carbon footprint per unit yield (product carbon footprint) was 0.80 (+0.02), 0.66 (+0.03) and 0.33 (+0.33) respectively. 0.02 kg CO_2-eq kg-1. Nitrogen fertilizer and agricultural machinery contributed 44-79% and 8-1.5% of the total carbon footprint respectively. Irrigation accounted for 19% and 25% of the total rice production emissions, respectively. However, irrigation accounted for only 2-3% of the carbon footprint of wheat and maize production. There are significant differences in rice carbon footprint, mainly due to the differences in nitrogen fertilizer and agricultural machinery input in the process of crop management. The carbon footprint of wheat and maize decreased by 22% - 28%, which was mainly attributed to the improvement of farmland management efficiency. The key ways to reduce greenhouse gas emissions were investigated. The results showed that the land use carbon footprint of greenhouse vegetable production was between 0.7 ~ (- 1) 0.4 tCO_2 - EQ ha ~ (- 1), and there was no difference among different vegetable types. However, the carbon footprint per unit yield (product) of pakchoi and amaranth was not different. 0.34 kg CO_2-eq kg-1 and 0.38 kg CO_2-eq kg-1, respectively, were significantly higher than those of other vegetable varieties (0.07-0.17 kg CO_2-eq kg-1), and the carbon emissions per unit income of pakchoi and amaranth production were also higher (1.95 kg CO_2-eq USD-1 and 1.82 kg CO_2-eq USD-1, respectively). Carbon emissions per unit nutrient value of Amaranth (0.12 kg CO_2-eq ANV-1) and Amaranth (0.36 kg CO_2-eq ANV-1), respectively, were lower. Fertilizer input contributed the most to carbon footprint, accounting for 55-82% of total vegetable production emissions, followed by organic fertilizer and irrigation, accounting for 2-21% and 1-26% of total emissions, respectively, with significant differences among different vegetable types. The contribution of pesticides to carbon footprint is the smallest, accounting for 5%, 5% and 2% of total emissions, respectively. Therefore, reducing the use of chemical fertilizers and increasing the use of organic fertilizers may be an important measure to reduce emissions in vegetable production. Carbon footprint of major fruit production in China was evaluated, and the contrast between land use carbon footprint and fruit product carbon footprint was clarified. It was pointed out that fertilization management was an important way to reduce emissions in orchards. The results showed t ha t the carbon footprint per unit area (land use carbon footprint) ranged from 2.9 t CO_2-eq ha~(-1) to 12.8 t CO_2-eq ha~(-1) and the carbon footprint per unit yield (fruit product carbon footprint) ranged from 0.07 kg CO_2-eq kg~(-1) in all orchards surveyed. - 1) to 0.7 kg CO_2-eq kg-1. Here, the land use carbon footprint of fruit production was significantly higher than that of grain crops, but the carbon footprint of fruit products was significantly lower than that of grain crops. The carbon footprint of citrus and pear products (0.14 and 0.18 kg CO_2-eq kg-1, respectively) was significantly lower than that of apple, banana and peach (0.24, 0.27 and 0.37 kg CO_2-eq kg-1, respectively). However, according to the nutritional value of different fruits, the carbon emission intensity per unit nutritional value of citrus (average 0.5 kg CO_2-eq g-1) Vc) was significantly lower than that of other fruits (3.0-5.9 kg CO_2-eq g-1) Vc). In addition, the carbon emission intensity per unit income of citrus and pear (average 0.5 kg CO_2-eq US-1) Vc) was significantly lower than that of other fruits (3.0-5.9 kg CO_2-eq g-1). D~(-1) was significantly higher than that of apples, bananas and peaches (0.87-0.39 kg CO_2-eq USD~(-1)). Chemical nitrogen was the most important contributor in orchard management, accounting for 47-75% of total greenhouse gas emissions. Our research suggests that low-carbon fruit consumption should be encouraged, and at the same time, how to balance the nutritional needs of people and the economic interests of fruit farmers is an important policy consideration. Developing large-scale management and intensive management can improve the efficiency of agricultural production. Farmers with different management scales (large households, more than 3.3ha; small households, less than 3.3ha) around Poyang Lake are selected with great emission reduction potential. The rice production and management situation are investigated in detail, and the rice production (early rice, late rice) under different management scales is analyzed and compared. The carbon footprint of early rice was the lowest, followed by single-cropping rice, and the highest (carbon footprint per unit area and yield per unit area) of late rice were: early rice, 4.54 (+0.44 t) CO_2-eq ha~(-1) and 0.62 (+0.1 kg) CO_2-eq kg~(-1); single-cropping rice, 6.84 (+0.79 t) CO_2-eq ha~(-1) and 0.80 (+0.13 kg) CO_2-eq ha~(-1), respectively. Nitrogen fertilizer application and methane emission from rice paddy fields were the biggest contributors to carbon emissions from rice production, accounting for 33% and 57% of the total carbon footprint respectively. Compared with the small households, the carbon footprint of double-cropping rice products (0.86 0.11 kg CO_2-eq kg-1) was lower in large households than that of small households (1.14.25 kg CO_2-eq kg-1). 25% is mainly due to the improvement of nitrogen use efficiency and the reduction of methane emission under good water management under large-scale planting mode. Therefore, optimizing farmland management mode and developing large-scale planting mode are important strategies to reduce greenhouse gas emissions in China's agriculture. The results showed that there were significant differences in rice carbon footprint among the three management modes of decentralized management (retail household), intensive production (non-polluted farm) and organic production (organic farm). The carbon footprint of rice products under retail management (0.80 kg CO_2-eq kg-1) was significantly higher than that of organic farms (0.56 kg CO_2-eq kg-1) and intensive management (0.56 kg CO_2-eq kg-1)). The difference was mainly manifested in the differences of fertilizer and pesticide input and irrigation management activities. Under intensive and organic production management, the carbon costs of these three inputs were significantly reduced, while under retail management, the emissions of irrigation electricity and direct methane emissions from paddy fields were significantly higher than those under farm management. These results indicate that intensive farm management is a low-carbon and High-yielding mode of agricultural production, which still has significant potential to reduce emissions and improve. Retail household management may be a general task for China's agricultural greenhouse gas emission reduction. 5. Statistics and measurement of global research literature reveal that an important way to improve the utilization rate of nitrogen fertilizer is to increase the uptake and utilization of residual nitrogen in soil by crops. It is proposed that nitrogen fertilizer is an important direction for guiding rational application of nitrogen fertilizer and greenhouse gas emission reduction in agricultural production. Indispensable external inputs, but the problem of nitrogen use efficiency has been plaguing fertilizer use and environmental management. Published English literature on nitrogen fertilizer field trials worldwide has been collected, fertilizer, soil, crop-related data and 15N-labeled abundance data have been obtained, and a database has been established to analyze and assess the fate of fertilizer nitrogen and the uptake of nitrogen by crops. The results showed that the proportion of crop nitrogen derived from fertilizer nitrogen was less than half on average, and most of the nitrogen was directly or indirectly derived from soil nitrogen. Compared with inorganic fertilizers, organic fertilizers (manure, green manure, compost, etc.) have an average nitrogen recovery rate of 29% in the current crop season, but the nitrogen recovery rate in the later crop season can reach 10%. It can be considered that most of the non-fertilizer nitrogen in crops comes from the turnover of residual nitrogen in soil and crops, but in the later season. In the past, the most important source of crop nitrogen, soil nitrogen, was neglected in the consideration of increasing the utilization rate of fertilizer nitrogen. It may be an important way to improve the utilization rate of nitrogen fertilizer by paying attention to increasing crop uptake and utilization of residual fertilizer nitrogen in soil and applying organic nitrogen fertilizer rationally. Carbon footprints of major crop production (including grain crops, greenhouse vegetables and fruits) in China were compared under different environmental conditions, different management scales and different management modes. The characteristics of carbon footprints in agricultural production and the differences of carbon emissions in different industries were explored, and low-carbon production was provided for policy makers. At the same time, the study on the fate of nitrogen fertilizer and the source of crop nitrogen in agricultural system suggests that the utilization of soil residual nitrogen is an important way to improve the utilization rate of nitrogen fertilizer, and supports the important significance of organic fertilizer in improving the utilization rate of nitrogen fertilizer and reducing greenhouse gas emissions. Problems and challenges in assessing the environmental impact of agricultural production, such as how to balance land use carbon intensity with agricultural product carbon intensity (vice versa)
【学位授予单位】：南京农业大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：S181;S143.1
本文编号：2230155
[Abstract]:Since the Industrial Revolution, human activities have led to a rapid increase in global greenhouse gas emissions. Increases in carbon dioxide (CO 2) emissions are mainly due to fossil fuel combustion and land use change, while methane and nitrous oxide emissions are mainly from agriculture. Agriculture contributes 11% of the total anthropogenic greenhouse gas emissions in China, accounting for anthropogenic sources, respectively. Methane (CH_4) and nitrous oxide (N_2O) emissions account for 52% and 84%. Improving crop production management is a major scientific and technological potential for mitigating global greenhouse gas emissions in agriculture. Field farm survey, literature collection and data acquisition, using life cycle analysis, the main research contents: (1) quantify the carbon footprint and its composition of China's agricultural production (grain crops, vegetables and fruits); (2) analyze and compare the differences of carbon footprint of agricultural production under different management scale, different management modes and different environmental conditions; (3) nitrogen fertilizer application is the cause The main reasons for the high emission of agricultural production were studied and analyzed. A methodological system for systematically assessing the carbon footprint of agricultural production was established. The key ways and technical choices for reducing greenhouse gas emissions in agriculture were put forward, which provided scientific basis for sustainable agricultural production management and low carbon consumption of food. The main results are as follows: 1. Quantifying the carbon footprint of major grain crops in China and identifying the key ways to reduce greenhouse gas emissions in agriculture The results showed t ha t the carbon footprint per unit area (land use carbon footprint) of rice, wheat and maize were 6.0 (+0.1), 3.0 (+0.2) and 2.3 (+0.1) t CO_2-eq ha-1, respectively, while the carbon footprint per unit yield (product carbon footprint) was 0.80 (+0.02), 0.66 (+0.03) and 0.33 (+0.33) respectively. 0.02 kg CO_2-eq kg-1. Nitrogen fertilizer and agricultural machinery contributed 44-79% and 8-1.5% of the total carbon footprint respectively. Irrigation accounted for 19% and 25% of the total rice production emissions, respectively. However, irrigation accounted for only 2-3% of the carbon footprint of wheat and maize production. There are significant differences in rice carbon footprint, mainly due to the differences in nitrogen fertilizer and agricultural machinery input in the process of crop management. The carbon footprint of wheat and maize decreased by 22% - 28%, which was mainly attributed to the improvement of farmland management efficiency. The key ways to reduce greenhouse gas emissions were investigated. The results showed that the land use carbon footprint of greenhouse vegetable production was between 0.7 ~ (- 1) 0.4 tCO_2 - EQ ha ~ (- 1), and there was no difference among different vegetable types. However, the carbon footprint per unit yield (product) of pakchoi and amaranth was not different. 0.34 kg CO_2-eq kg-1 and 0.38 kg CO_2-eq kg-1, respectively, were significantly higher than those of other vegetable varieties (0.07-0.17 kg CO_2-eq kg-1), and the carbon emissions per unit income of pakchoi and amaranth production were also higher (1.95 kg CO_2-eq USD-1 and 1.82 kg CO_2-eq USD-1, respectively). Carbon emissions per unit nutrient value of Amaranth (0.12 kg CO_2-eq ANV-1) and Amaranth (0.36 kg CO_2-eq ANV-1), respectively, were lower. Fertilizer input contributed the most to carbon footprint, accounting for 55-82% of total vegetable production emissions, followed by organic fertilizer and irrigation, accounting for 2-21% and 1-26% of total emissions, respectively, with significant differences among different vegetable types. The contribution of pesticides to carbon footprint is the smallest, accounting for 5%, 5% and 2% of total emissions, respectively. Therefore, reducing the use of chemical fertilizers and increasing the use of organic fertilizers may be an important measure to reduce emissions in vegetable production. Carbon footprint of major fruit production in China was evaluated, and the contrast between land use carbon footprint and fruit product carbon footprint was clarified. It was pointed out that fertilization management was an important way to reduce emissions in orchards. The results showed t ha t the carbon footprint per unit area (land use carbon footprint) ranged from 2.9 t CO_2-eq ha~(-1) to 12.8 t CO_2-eq ha~(-1) and the carbon footprint per unit yield (fruit product carbon footprint) ranged from 0.07 kg CO_2-eq kg~(-1) in all orchards surveyed. - 1) to 0.7 kg CO_2-eq kg-1. Here, the land use carbon footprint of fruit production was significantly higher than that of grain crops, but the carbon footprint of fruit products was significantly lower than that of grain crops. The carbon footprint of citrus and pear products (0.14 and 0.18 kg CO_2-eq kg-1, respectively) was significantly lower than that of apple, banana and peach (0.24, 0.27 and 0.37 kg CO_2-eq kg-1, respectively). However, according to the nutritional value of different fruits, the carbon emission intensity per unit nutritional value of citrus (average 0.5 kg CO_2-eq g-1) Vc) was significantly lower than that of other fruits (3.0-5.9 kg CO_2-eq g-1) Vc). In addition, the carbon emission intensity per unit income of citrus and pear (average 0.5 kg CO_2-eq US-1) Vc) was significantly lower than that of other fruits (3.0-5.9 kg CO_2-eq g-1). D~(-1) was significantly higher than that of apples, bananas and peaches (0.87-0.39 kg CO_2-eq USD~(-1)). Chemical nitrogen was the most important contributor in orchard management, accounting for 47-75% of total greenhouse gas emissions. Our research suggests that low-carbon fruit consumption should be encouraged, and at the same time, how to balance the nutritional needs of people and the economic interests of fruit farmers is an important policy consideration. Developing large-scale management and intensive management can improve the efficiency of agricultural production. Farmers with different management scales (large households, more than 3.3ha; small households, less than 3.3ha) around Poyang Lake are selected with great emission reduction potential. The rice production and management situation are investigated in detail, and the rice production (early rice, late rice) under different management scales is analyzed and compared. The carbon footprint of early rice was the lowest, followed by single-cropping rice, and the highest (carbon footprint per unit area and yield per unit area) of late rice were: early rice, 4.54 (+0.44 t) CO_2-eq ha~(-1) and 0.62 (+0.1 kg) CO_2-eq kg~(-1); single-cropping rice, 6.84 (+0.79 t) CO_2-eq ha~(-1) and 0.80 (+0.13 kg) CO_2-eq ha~(-1), respectively. Nitrogen fertilizer application and methane emission from rice paddy fields were the biggest contributors to carbon emissions from rice production, accounting for 33% and 57% of the total carbon footprint respectively. Compared with the small households, the carbon footprint of double-cropping rice products (0.86 0.11 kg CO_2-eq kg-1) was lower in large households than that of small households (1.14.25 kg CO_2-eq kg-1). 25% is mainly due to the improvement of nitrogen use efficiency and the reduction of methane emission under good water management under large-scale planting mode. Therefore, optimizing farmland management mode and developing large-scale planting mode are important strategies to reduce greenhouse gas emissions in China's agriculture. The results showed that there were significant differences in rice carbon footprint among the three management modes of decentralized management (retail household), intensive production (non-polluted farm) and organic production (organic farm). The carbon footprint of rice products under retail management (0.80 kg CO_2-eq kg-1) was significantly higher than that of organic farms (0.56 kg CO_2-eq kg-1) and intensive management (0.56 kg CO_2-eq kg-1)). The difference was mainly manifested in the differences of fertilizer and pesticide input and irrigation management activities. Under intensive and organic production management, the carbon costs of these three inputs were significantly reduced, while under retail management, the emissions of irrigation electricity and direct methane emissions from paddy fields were significantly higher than those under farm management. These results indicate that intensive farm management is a low-carbon and High-yielding mode of agricultural production, which still has significant potential to reduce emissions and improve. Retail household management may be a general task for China's agricultural greenhouse gas emission reduction. 5. Statistics and measurement of global research literature reveal that an important way to improve the utilization rate of nitrogen fertilizer is to increase the uptake and utilization of residual nitrogen in soil by crops. It is proposed that nitrogen fertilizer is an important direction for guiding rational application of nitrogen fertilizer and greenhouse gas emission reduction in agricultural production. Indispensable external inputs, but the problem of nitrogen use efficiency has been plaguing fertilizer use and environmental management. Published English literature on nitrogen fertilizer field trials worldwide has been collected, fertilizer, soil, crop-related data and 15N-labeled abundance data have been obtained, and a database has been established to analyze and assess the fate of fertilizer nitrogen and the uptake of nitrogen by crops. The results showed that the proportion of crop nitrogen derived from fertilizer nitrogen was less than half on average, and most of the nitrogen was directly or indirectly derived from soil nitrogen. Compared with inorganic fertilizers, organic fertilizers (manure, green manure, compost, etc.) have an average nitrogen recovery rate of 29% in the current crop season, but the nitrogen recovery rate in the later crop season can reach 10%. It can be considered that most of the non-fertilizer nitrogen in crops comes from the turnover of residual nitrogen in soil and crops, but in the later season. In the past, the most important source of crop nitrogen, soil nitrogen, was neglected in the consideration of increasing the utilization rate of fertilizer nitrogen. It may be an important way to improve the utilization rate of nitrogen fertilizer by paying attention to increasing crop uptake and utilization of residual fertilizer nitrogen in soil and applying organic nitrogen fertilizer rationally. Carbon footprints of major crop production (including grain crops, greenhouse vegetables and fruits) in China were compared under different environmental conditions, different management scales and different management modes. The characteristics of carbon footprints in agricultural production and the differences of carbon emissions in different industries were explored, and low-carbon production was provided for policy makers. At the same time, the study on the fate of nitrogen fertilizer and the source of crop nitrogen in agricultural system suggests that the utilization of soil residual nitrogen is an important way to improve the utilization rate of nitrogen fertilizer, and supports the important significance of organic fertilizer in improving the utilization rate of nitrogen fertilizer and reducing greenhouse gas emissions. Problems and challenges in assessing the environmental impact of agricultural production, such as how to balance land use carbon intensity with agricultural product carbon intensity (vice versa)
【学位授予单位】：南京农业大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：S181;S143.1
【相似文献】
相关期刊论文 前10条
1 曹淑艳;谢高地;;中国产业部门碳足迹流追踪分析[J];资源科学;2010年11期
2 ;消除碳足迹 企业在行动[J];绿化与生活;2011年02期
3 胡炜;;减少碳足迹,你我须努力[J];创新科技;2012年05期
4 芮加利;王子彦;;减少碳足迹的政府作为[J];环境保护与循环经济;2009年03期
5 吴明;;追寻“碳足迹”[J];大众标准化;2009年10期
6 王微;林剑艺;崔胜辉;吝涛;;碳足迹分析方法研究综述[J];环境科学与技术;2010年07期
7 罗运阔;周亮梅;朱美英;;碳足迹解析[J];江西农业大学学报(社会科学版);2010年02期
8 秦却;;“碳足迹”行动[J];新经济导刊;2010年04期
9 王奉安;;碳足迹——环保新坐标[J];环境保护与循环经济;2010年07期
10 祁悦;谢高地;盖力强;张彩霞;李士美;;基于表观消费量法的中国碳足迹估算[J];资源科学;2010年11期
相关会议论文 前10条
1 陈展展;;各国碳足迹评估工作概览及其启示[A];经济发展方式转变与自主创新——第十二届中国科学技术协会年会（第一卷）[C];2010年
2 王立国;廖为明;黄敏;邓荣根;;基于终端消费的旅游碳足迹测算[A];第八届博士生学术年会论文摘要集[C];2010年
3 董雪;柯水发;;国内外碳足迹计算方法、评估标准及研究进展[A];绿色经济与林业发展论——第六届中国林业技术经济理论与实践论坛论文集[C];2012年
4 曹磊;刘尊文;岳文淙;;中国产品碳足迹评价制度设计初探[A];2013中国环境科学学会学术年会论文集（第四卷）[C];2013年
5 郑凯;陈学渊;韦文珊;吴永常;;农村社区碳足迹的内涵与计算方法研究[A];中国人口·资源与环境2013年专刊——2013中国可持续发展论坛（一）[C];2013年
6 梁淳淳;宋燕唐;云鹭;;产品碳足迹标准化研究[A];市场践行标准化——第十一届中国标准化论坛论文集[C];2014年
7 李志强;刘春梅;;碳足迹及其影响因素分析——基于中部六省的实证[A];2009年南昌大学中国中部经济发展研究中心学术年会暨“贯彻国务院《促进中部地区崛起规划》”研讨会论文集[C];2009年
8 ;碳足迹与碳标签[A];江苏纺织学会通讯（总第127期）[C];2011年
9 赵先贵;肖玲;郝高建;高利峰;戴兵;;陕西省铜川市碳足迹动态分析[A];2013中国环境科学学会学术年会论文集（第二卷）[C];2013年
10 李志强;刘春梅;;碳足迹及其影响因素分析——基于中部六省的实证[A];第六届中国科技政策与管理学术年会论文集[C];2010年
相关重要报纸文章 前10条
1 本报记者 石琨;“碳足迹”计算该信谁[N];文汇报;2009年
2 记者 高天宇;专家：碳足迹标准不权威[N];国际商报;2010年
3 记者 张丽娜;油墨企业降低能耗减控碳足迹[N];消费日报;2010年
4 郑平;大学生用行为艺术宣传“碳足迹”[N];科技日报;2008年
5 资深媒体人士 林益楷;让“碳足迹”更加透明化[N];中国能源报;2010年
6 特约编译 王晋;新西兰葡萄酒企业率先标明碳足迹[N];华夏酒报;2010年
7 青石;碳足迹标准将制约石材出口[N];中国建材报;2011年
8 杨威;新民科技成为 吴江首批“碳足迹”认证企业[N];中国纺织报;2011年
9 记者 罗晖;中粮两产品获碳足迹盘查第三方国际认证[N];科技日报;2012年
10 本报记者 苏南;碳足迹盘查仍处初级阶段[N];中国能源报;2012年
相关博士学位论文 前6条
1 徐中岳;从单元操作角度研究不同冻结和冻藏方式对猪肉碳足迹和质量的影响[D];华南理工大学;2016年
2 闫明;农业生产碳足迹及氮肥去向的计量研究[D];南京农业大学;2015年
3 林涛;天津市能源消耗碳足迹影响因素研究[D];天津大学;2013年
4 冯超;城市框架内的碳足迹量化方法及影响因素研究[D];华南理工大学;2014年
5 程永宏;碳排放政策下供应链定价与产品碳足迹决策及协调研究[D];重庆大学;2015年
6 田慎重;基于长期耕作和秸秆还田的农田土壤碳库演变、固碳减排潜力和碳足迹分析[D];山东农业大学;2014年
相关硕士学位论文 前10条
1 丁华艳;洪泽湖湿地生态旅游碳足迹研究[D];西华师范大学;2015年
2 梁修如;我国出口谷物产品的碳足迹分析[D];中国科学技术大学;2015年
3 方蕾;基于生命周期理论的船舶碳足迹研究[D];宁波大学;2015年
4 朱捷;松嫩平原旱作农田土壤CO_2排放规律及碳足迹研究[D];东北农业大学;2015年
5 肖圣杰;中国30省市碳足迹测算及影响因素研究[D];江西财经大学;2015年
6 周鹏飞;碳足迹评估对竹产品企业的潜在影响及策略选择[D];浙江农林大学;2015年
7 谢栌乐;基于灌溉效益和碳足迹的河北省农业可持续发展研究[D];河北科技大学;2015年
8 薛景洁;河南省旅游碳足迹测算及影响因素研究[D];燕山大学;2015年
9 江永楷;中国各地区及工业行业水-碳足迹核算及情景模拟研究[D];清华大学;2015年
10 徐延菊;基于碳足迹视角的安徽省种植业低碳化研究[D];安徽农业大学;2014年
，本文编号：2230155
本文链接：https://www.wllwen.com/kejilunwen/nykj/2230155.html
