【作者】 黄乐艳；

【导师】 闫文德；

【作者基本信息】 中南林业科技大学 ， 生态学， 2007， 硕士

【摘要】 城市森林在维持全球和区域性的生物地球化学循环与水分循环·,涵养水源与保持水土,净化环境,维持大气平衡以及居民身心健康等方面起着十分重要的作用。因而选择长沙城市森林生态系统为研究对象,通过野外调查与监测和室内实验相结合的方式,于2006年2月至2007年1月,对大气降水、穿透水、树干茎流和地表径流的水化学特性进行了研究。对其非金属元素(NH4+-N、NO3--N、P、SiO2)、金属元素(K、Ca、Mg、Cu、Fe、Zn、Mn)及其水环境参数(DO、pH、COND、TEMP、SAL)进行了分析测定,并运用综合指数法、模糊数学法和灰色关联度法对4种不同水体的水质进行综合评价,结果将为长沙城市森林水资源的管理提供理论依据。主要研究结果如下：(1)实验地全年总降水量为1189.8mm,与近十年平均年降水量相比,降雨偏少12.63%。大气降水中非金属元素浓度最大为NH4+-N,为1.808mg.L-1；最小为P,仅有0.092mg.L-1,从大到小排列为NH4+-N>SiO2>NO3--N>P;金属元素浓度最大为Ca,为3.401mg.L-1,最小为Mn,只有0.073mg.L-1,排列顺序为Ca>K>Zn> Mg>Fe>Cu>Mn。穿透水中非金属元素浓度最大为SiO2,达到5.214mg.L-1,最小的元素为P,只有0.145mg.L-1。排序为SiO2>NH4+-N>NO3--N>P；金属元素浓度最大为Ca,为12.626mg.L-1,最小为Fe,只有0.055mg.L-1,排列顺序为Ca>K>Mg>Zn>Mn>Cu>Fe。除Cu、Fe、Zn、pH、DO外,林内雨水质浓度比天然降雨水质的浓度有所增加。其中增加幅度最大的为K,达到742.7%,其次是Mg,为606%,增加幅度最小的为TEMP,仅有1%,其次是P,为56.6%。水环境参数方面,pH,DO表现为大气降水>穿透水,COND、SAL则相反,TEMP变化趋势不明显。(2)4个树种茎流中化学元素除Cu元素表现为春、冬季高,夏、秋季低外,其他元素的浓度变化较大,具有明显的季节动态变化,即表现为秋冬季高,春、夏季低；pH最高的为木荷(Mang lietia fordiana),为6.15,最低的为湿地松(Pinus ellotii),只有4.26；而COND最大的为湿地松,达到0.721ms/cm,最小的为木荷,为0.25ms/cm,这与pH恰好相反；而DO都维持在6～7.5mg.L-1之间,变化幅度小；它们的TEMP和SAL变化不大。(3)在所有化学元素浓度中,Ca浓度最高,为32.494mg.L-1；而营养元素输入方面,Cu、P、Fe、Zn为负值,迁移量分别为0.037mg.L-1、0.082mg.L-1、0.088mg.L-1、0.201mg.L-1,这4种元素即为淋失迁移型,而NH4+-N、NO3--N、SiO2、K、Ca、Mg、Mn等元素为内贮型,其中迁移量最大的元素为K,达到29.64mg.L-1,其次为Ca,为27.566mg.L-1。迁移系数最大的为K,为25.99,最小为P,只有0.11,K与P相差236.27倍。(4)大气降水与穿透水、树干茎流、地表径流显著性的概率分别为0.012、0.008、0.027,小于0.05,因而大气降水与穿透水、树干茎流、地表径流具有显著差异。(5)采用综合指数法、模糊数学法和灰色关联度法对大气降水、树干茎流、穿透水以及地表径流水质进行综合评价。由于樟树(Cinnamomum camphora)、木荷、湿地松以及莽草(Lllicium lanceolautum)4个树种的树干茎流水质两两间显著性的概率都大于0.05,说明它们间的水质无明显差异,选择优势树种—樟树的树干茎流为代表进行水质评价。结果大气降水为Ⅲ级标准,已经被轻度污染；而树干茎流属Ⅳ类水；穿透水与地表径流都符合Ⅲ级标准。三种评价方法的综合评价结果与其中的综合指数法的评价结果一致,因而建议城市森林的水质评价采用综合指数法。更多还原

【Abstract】 Urban forest play an important role on maintaining the global and region biogeochemical cycles and water cycle,conserving water and controlling water and soil erosion, cleaning environment, maintaining the atomosphere balance and the inhabitants’healthy in mind and body.So choose the urban forest ecosystem for the study.From February,2006 to January,2007, through the ways and means comprise survey of field investigative and interior experiment, and take the biogeochemical character of rainfall, throughfall, stemflow and undergroudfall as the contents for study, the elements of nonmetal like NH4+-N,NO3--N,P,SiO2, elements of metal like K, Ca, Mg, Cu, Fe, Zn, Mn and water enviroment parameter such as DO,pH,COND,TEMP,SAL was analysed.In order to understand the improvement of the forest ecosystem of Changsha City to water quality,evaluation methods included general index,blur-mathematics and grey incidence Conseque-ntly,which can offer theoretical sustain to the construction and management for Urban Forestry of Changsha City.Main research results:(1) Result indicated that the total rainfall was 1189.8mm in the research period,which reduce 12.63% compare with annual average rainfall of the latest 10 years.The maximum concetration of nonmetal of rainfall was NH4+-N,got 1.808 mg.L-1 the min was P,only 0.092mg.L-1,the order was NH4+-N>SiO2>NO3--N>P; The maximum concetration of metal was Ca,got 3,401mg.L-1,min was Mn,only 0.073mg.L-1,the order was Ca>K>Zn>Mg>Fe>Cu>Mn.The maximum concetration of nonmetal of throughfall was SiO2,got 5.214mg.L-1,the min was P,only 0.145mg.L-1,the order was SiO2>NH4+-N>NO3--N >P;The maximum concetration of metal was Ca,got 12.626mg.L-1,min was Fe,only 0.055mg.L-1,the order was Ca>K>Mg>Zn>Mn>Cu>Fe.Except for nutrient elements like pH,DO,Cu,Fe,the concentration of inside forest increase comparing with rain outside forest.Among of them,mostly increase was K,reached 742.7%, then was Mg,reached 606%,in the opposite,smally increase was TEMP,onlyl%,then was P, got 56.6%.At the aspect of water enviroment parament,pH,DO,performance rainfall> throughfall,COND,SAL was oppsite.Tendence of TEMP was not obvious.(2) In 4 tree species,besides the nutrient element Cu performanced that concentration was high in spring and winter,low in summer and autumn,the other nutrient elements content fluctuated,but all of them tent to consistently and all displayed for high in the fall and winter,low in spring and summer.pH was higgest in Mang lietia fordiana,was 6.15,lowest was Pinus ellotii,only 4.26;COND was highest in Pinus ellotii,reached 0.721ms/cm,lowest in Mang lietia fordiana,was 0.25ms/cm,thwas was oppsite on pH;DO maintained 6-7.5,change scope was small;their TEMP and SAL also changed small.(3) In all of the chemical element content,the highest concentration was Ca,reached 32.494mg.L-1;But in the aspect of the nutritive elements input character, Cu, P, Fe, Zn was a negative value,their migration amout was 0.037 mg.L-1,0.082mg.L-1, 0.088mg.L-1 respectively,its showed that the 4 kinds of nutrient elements name type of leaching migration,but in another way,other nutrient elements like NH4+-N,NO3--N, SiO2,K,Ca,Mg,Mn was a storing type.The max migration amout was K,got 29.64mg.L-1, then was Ca,got 27.566mg.L-1.The max migration coefficient was K and min migration coefficient was P,their value was 25.99 and 0.11 respectivly,the max had 236.27 times of the min.(4) The remarkable probability between throughfall,stemflow,underground runoff and rainfall respectively for 0.012,0.008,0.027,was smaller than 0.05,so throughfall was remarkable different from the 3 other kinds of water quality.’(5) Evaluation methods included general index, blur-mathematics and grey incidence to evaluate rainfall,stemflow,throughfall and underground fall.Because remarkable probability of stemflow of 4 tree species was bigger than 0.05,so their water quality was not obvious.we can use Cinnamomum camphora’s stemflow to evaluate.The results showed:the water quality of rainfall reachedⅢdegree,polluted lightly;stemflow reached IV degree;Both throughfall and the underground runoff reachedⅢdegree.The general result of three methods was consistant with general index, so advised the water quality of urban forest take the general index as the method for evaluate.更多还原