【作者】 涂洁；

【导师】 刘琪璟；

【作者基本信息】 南昌大学 ， 环境工程， 2007， 博士

【摘要】 采用热扩散式探针法对湿地松（Pinus elliottii）树干液流密度及环境因子进行长期连续测定，同时辅以树干（枝条）解析等生长量调查方法，建立了我国亚热带红壤丘陵地带湿地松水分耗失与碳蓄积之间的耦合关系，主要结论如下：（1）湿地松胸径、树高、材积生长模型均以二次曲线的拟合优度最高，相关关系的判定系数在0.99以上。树干、树冠生长量与胸径生长量间均呈显著的幂函数相关关系，相关关系的判定系数分别为0.8242和0.9568。（2）阳坡向湿地松胸径生长主要受≥10℃积温、日照时数、和前一年降雨量影响，复相关系数为0.935；阴坡向胸径生长仅受相对湿度影响，相关系数为0.901。两坡向树高生长主要受均温、日照时数、相对湿度、前一年降雨量影响，复相关系数分别为0.827和0.882。两坡向材积生长主要受均温、≥10℃积温、日照时数、相对湿度影响，复相关系数分别为0.749和0.723。当年降雨量对该区湿地松生长不起限制作用。（3）各器官碳素含量为叶（52.62±0.38～54.38±0.26）％＞枝（51.18±0.55～52.26±0.41）％＞干材（51.41±0.39）％＞根（51.28±0.22～51.77±0.32）％＞干皮（50.92±0.46）％。灌木层、草本层、凋落物层碳素含量分别为（44.90±0.45～45.47±0.35）％、（42.13±0.44～42.42±0.39）％、（40.88±0.31）％。土壤（0～60cm）碳素含量为（0.26±0.07～0.65±0.06）％。生物量加权法得出湿地松林平均碳素含量为（51.71±0.37）％。19年生湿地松乔木层碳贮量为86.78t·hm^-2，年净固定CO₂量为16.77t·hm^-2，年净释O₂量为12.20t·hm^-2。各种方法计算出的固碳释氧效益在6072.31～10610.78元·hm^-2·a^-1波动。（4）湿地松各生长期白天液流密度的日变化规律基本一致，但液流启动、到达峰值及开始下降的时间存在差异。3～9月液流量分别占全年总量的4.3820％、7.7036％、17.2084％、18.4208％、14.3629％、11.2381％、8.8279％、7.5221％。整个生长期液流量占全年总量的89.6658％，非生长期仅占10.3342％。（5）湿地松边材面积与胸径（带皮）呈极显著二次函数相关，相关关系的判定系数达0.943。液流速率平均值、最大值与胸径均呈显著的幂函数关系，相关关系的判定系数均在0.98以上。各生长期日累计液流量与边材面积间均呈极显著的线性相关关系，相关系数的判定系数都在0.95以上。（6）液流密度与冠层温度、冠层相对湿度、光合有效辐射均呈显著的线性相关关系。液流密度与上述3个因子建立的多元线性回归方程相关性显著，各因子偏相关系数显著性检验的概率p均小于0.001。各气象因子与液流密度相关程度大小顺序为冠层相对湿度＞光合有效辐射＞冠层温度。（7）2004年整个湿地松标准地（20m×20m）耗水量为177.8526m³·a^-1，换算成单位面积上的水深为444.63mm·a^-1，低于该区多年平均降雨量（1000mm以上）。经预测，未来10年湿地松林分潜在耗水量（单位：mm）依次为469.76、494.92、520.28、545.66、571.13、596.67、622.28、647.96、673.72、699.54。湿地松水分利用效率为58.5123μmolCO₂·mmol^-1H₂O或1.7731g干物质·kg^-1H₂O。更多还原

【Abstract】 Whole-tree sap flow density （SFD） was measured on 6 trees continuously in anartificial Pinus elliottii forest using Granier’s thermal dissipation probe method withseveral environmental factors including meteorological variables and soil variablesmeasured simultaneously in Qian Yanzhou Experimental Station, located in Taihecounty, Jiangxi Province. At the same time, stem analysis and branch analysis wereutilized to investigate whole-tree growth. The aim of this paper was to explore thecoupling relationship between water consumption and carbon sequestration of P.elliottii and provide scientific methods and fundamental data for the research onwater-carbon coupling cycle in subtropical red earth hilly area of our country. Themain obtained results were as follows:First, significant quadratic correlations were found between three growth indexincluding diameter at breast height （DBH）, tree height, stem volume and tree age withall r² high above 0.99. Stem growth and crown growth both correlated significantlywith DBH increment in power function, with r² 0.8242 and 0.9568 separately.Second, the DBH increment of P. elliottii in sunny slope was mainly affected by≥10℃accumulated temperature （≥10℃AT）, sunshine hours （SH） and precipitation inthe year before （PB） with r² 0.935. The DBH increment in shady slope correlated onlywith relative humidity （RH） with r² 0.901. The height increment in both sunny slopeand shady slope were affected by average temperature （AT）, SH, RH, PB with r²0.827 and 0.882 separately. The volume increment in both slope sides dependedmainly on AT,≥10℃AT, SH, RH with r² 0.749 and 0.723 separately. Precipitation inthe current year had no limitation to P. elliottii growth in this area. The correlationtests for all equations were significant at the level of 0.05.Third, the carbon content in different organs of P. elliottii decreased in the order ofleaf （52.62±0.38～54.38±0.26） %＞branch （51.18±0.55～52.26±0.41） %＞wood（51.41±0.39） %＞root （51.28±0.22～51.77±0.32） %＞bark （50.92±0.46）%. Thecarbon content in branches and leaves increased with the age of organs. The leaf carbon content of mid-layer was slightly higher than that of the mid-and up-layers.And the branch carbon content of the down-layer was much higher than that of theother two layers. The carbon content in shrub, herb and litter floor was （44.90±0.4545.47±0.35） %, （42.13±0.44～42.42±0.39）%, （40.88±0.31）%, respectively. Theaverage carbon content in the soil ranged between （0.26±0.07）% and （0.65±0.06）%, and declined with the soil depth. The average carbon content of P. elliottiicalculated from biomass weight methods was ablout （51.71±0.37）%. The totalcarbon storage of 19-year-old P. elliottii over storey amounted to 86·18t·hm^-2. Theannual net CO₂ fixation and O₂ production were calculated as 16.77t·hm^-2 and12.20t·hm^-2separately. The benefits from CO₂ fixation and O₂ estimated fromdifferent methods varied in the range of 6072.31～10610.78yuan.hm^-2·a^-1.Fourth, diurnal sap flow in different growing periods was basically similar. Butsome differences still occurred in the time of starting, reaching peaks and descending.The accumulative sap flux from March and September accounted for 4.3820%,7.7036%, 17.2084%, 18.4208%, 14.3629%, 11.2381%, 8.8279%, and 7.5221% of thewhole-year sap flux separately. To sum up, the growing periods and non-growingperiods occupied 89.6658% and 10.3342.% of total sap flux, respectively.Fifth, a significant quadratic correlation was found between sapwood area （SWA）and DBH with r² 0.943 of P. elliottii. SFD correlated well with DBH in powerfunctions with r² higher than 0.98. Daily cumulative sap flow in different growingperiods correlated linearly with sapwood area with all r² higher than 0.95.Six, SFD was mainly affected by three meteorological factors including canopytemperature （CT）, canopy relative humidity （CRH） and photosynthetically activeradiation （PAR）. Correlations between, SFD and the three separate factors wereexpressed well by linear regression models. Multiple-linear model between SFD andthe three integrated factors was also established. All equations and correlationparameters were significant at the level of 0.01. The sequence of correlated degrees ofthree factors was as follows: CRH＞PAR＞CT.（7） The total water consumption of P. elliottii stand （20m×20m） in 2004 was177.8526m³·a^-1(444.63mm·a^-1 expressed as water depth per area), much lower thanthe average annual precipitation （1000mm） in this area. Estimated from potential water consumption model, the water consumption of P elliottii plantation in futural10 years were 469.76mm, 494.92mm, 520.28mm, 545.66mm, 571.13mm, 596.67 mm,622.28mm, 647.96mm,673.72mm,699.54mm. Based on the results of tree growth andwater use, the WUE of P. elliottii was calculated as 58.5123μmolCO₂·mmol^-1H₂O or1.7731 gDW-kg^-1H₂O.更多还原