【作者】 李萍；

【导师】 郑有飞；

【作者基本信息】 南京信息工程大学 ， 环境科学， 2012， 硕士

【摘要】 近年来,地表太阳辐射减弱强度和03浓度升高均呈增加趋势,太阳辐射减弱和O3增加会影响作物的生长发育及作物对N、P元素的吸收。本文基于开顶式气室(OTC)和黑色遮阳网模拟地表03浓度增加和太阳辐射减弱情况,共设置了9个实验处理：CKl(野外大田组,完全自然环境)；S1(太阳辐射减弱20%)；S2(太阳辐射减弱40%)；S3(太阳辐射减弱60%)；CK2(仅增加OTC气室,不进行03曝气和遮光)；T(03浓度为100±8n1·L-1)；TS1(T与S1复合),TS2(T与S2复合),TS3(T与S3复合)。研究了整个生育期内太阳辐射减弱和03胁迫对冬小麦各器官中N、P元素和麦田耕层土壤理化性质、土壤酶活性的影响。主要结论如下：(1)太阳辐射减弱(S1、S2、S3)会增大土壤含水量,导致根区土壤全N和速效K含量增大,土壤速效P含量降低；太阳辐射减弱会增大冬小麦各器官中N、P含量,且根、茎和营养器官中N、P含量均与太阳辐射减弱强度呈极显著正相关,降低根中N、P累积量和分配率,增大叶中N、P累积量,降低营养器官中N、P的总转运量和转运率。(2)单因子03增加(T)会降低土壤过氧化氢酶活性,增大土壤脲酶活性,增大土壤速效P、K和全P、K含量；T处理会增大冬小麦各器官中N、P含量和营养器官中N、P的总转运率,降低叶中N、P的转运量,降低冬小麦各器官中P的累积量,降低出苗-抽穗期根、茎、叶对N、P的阶段累积吸收,降低抽穗期-成熟期穗中P的阶段累积吸收和根、茎、叶中P的阶段输出量,增大抽穗期-成熟期根、茎和营养器官中N的阶段输出量。(3)不同程度的太阳辐射减弱条件下的03增加处理(TS1、TS2、TS3)会增大冠层空气日平均相对湿度,降低冠层空气日平均温度；增大孕穗期-成熟期冬小麦各器官中N、P含量,降低营养器官对N的总累积吸收和植株对P的总累积吸收,降低根、叶和营养器官中N、P的转运量及穗中P的累积和分配,且叶中N、P的转运量随着太阳辐射强度的降低而降低,降低出苗期-抽穗期茎、叶对N、P元素的阶段累积吸收,降低抽穗期-成熟期茎、叶中N、P的输出量和穗中P的阶段累积吸收。(4)土壤含水量与冬小麦各器官中N、P含量显著正相关,与各器官中N、P累积量显著负相关,土壤pH值与各营养器官中N、P含量显著负相关。通径分析表明,土壤含水量增大对营养器官中N、P含量的直接促进作用最大,但是在一定程度上对营养器官中N、P的总累积量会产生直接阻碍作用,日平均太阳瞬时辐射强度对营养器官中N、P的总累积量的直接促进作用最大。更多还原

【Abstract】 In recent years, the weakening of the surface solar radiation and elevated O3showed an increasing trend, the decreased solar radiation and increased O3will affect crop growth and absorption of N, P elements. In this paper, we simulated the enhanced O3concentration and reduced solar radiation by using open-top chamber (OTC) and black shade nets, set up9experimental treatments:CK1(field cornfield group, completely natural environment); S1(solar radiation attenuated by20%); S2(solar radiation weakened40%); S3(solar radiation weakened60%); CK2(only add the chamber without ozone aeration and shading); T(O3concentration of100±8n1·L-1); TS1(T and S1composite), TS2(T and S2composite), TS3(T and S3composite). Research was conducted comprehensive under the reduced solar radiation and enhanced O3conditions to detect the regularity of N、P concentration in different organ of winter wheat plants (Triticum aestivum L, Yang Mai13), cornfield topsoil physicochemical properties and soil enzyme activity. The main results indicated as follows:(1) The treatments of decreased solar radiation (S1, S2, S3) was increased soil moisture, increased the concentration of soil total N and available K, decreased soil available P concentration; The shading treatments increased the concentration of N, P in root, stem, leaf and vegetative organ, and N、P concentration in root, stem and nutritorium and the sun radiation abate strength was showed a significant positive correlation, the decreased solar radiation treatments reduced N, P cumulant and distribution rate of root, increased N and P cumulant of leaf, reduced the total transfer volume and transfer rates of N and P in the nutritorium.(2) The treatments (T) of single increasing O3concentration was reduced soil catalase activity, increased urease activity and concentration of soil available P, K and total P, K; increased N, P concentration in the various organs of winter wheat and N, P total transfer rates of nutritorium, reduced translocation amount of N, P of leaf, reduced the cumulant of P in various organs of winter wheat, reduced the stage accumulation of N, P in root, stem and leaf in the seeding stage-heading stage, reduced the stage accumulation of P in spike and the phase output of P cumulant in root, stem and leaf during the heading stage and the maturity stage, increased output of N cumulant in root, stem and vegetative organ in the heading stage-mature stage.(3) The treatmens of increased O3under different levels of reduced solar radiation conditions (TS1, TS2, TS3) increased canopy air relative humidity, reduced the daily average temperature of canopy air, promoted N and P concentration in different organs of winter wheat plant, reduced the total N cumulant of nutritorium and the P cumulant in winter wheat plant, decreased N, P transfer amount in root, leaf and nutritorium, reduced P cumulant and distribution rates in spike, decreased the stage accumulation of N, P in stem and leaf during seeding stage and heading stage, reduced N, P phase output of stem, leaf and P cumulated absorption of spike in the heading stage-mature stage, and the N, P transfer amount was reduced as the weaken intensity of solar irradiance.(4) The soil moisture and N, P concentration in various organs of winter wheat was showed a significant positive correlation, showed a significant negative related with N, P cumulant in the different organs, soil pH was significant negative correlated with N, P concentration in various nutrient organs. Path analysis showed that soil moisture increases promoted N, P concentration in nutritorium of the largest direct role, but produced direct impediment on N, P total cumulant in nutritorium to some extent, daily average solar instantaneous radiation intensity had the largest role in direct promoting N, P total cumulant in nutritorium of winter wheat.更多还原