【作者】 李文娟；

【导师】 黄庆丰；

【作者基本信息】 安徽农业大学 ， 森林经理学， 2010， 硕士

【摘要】 滩地是平原河床季节性淹水的微地形。滩地林业在生产中发挥着重要的作用,有效地缓解了“地少人多”的人地矛盾。因此,在国民经济中占有举足轻重的地位。然而不科学的滩地利用使滩地利用效益低下,不但对滩地造成了破坏,而且也引发了严重的环境问题和生态灾害。这些生态环境问题影响到了滩区社会经济的可持续发展,有效地开发利用滩地资源成为当前迫切需要解决的问题,皖河滩地造林模式及杨树修枝短期效应研究是解决该问题的前提和基础。在研究过程中,充分借鉴了中国森林生态系统网络体系建设“线”的研究与示范专题的研究成果,吸取了长江中、下游“以林为主”综合开发、“植树造林、抑螺防病”的成功经验。重点研究内容包括三个方面:不同杨树品系苗木生长规律与对比试验研究,2)滩地造林模式对比试验研究,3)不同修枝强度对比试验研究。初步得出以下结论:1)杨树四品系地径、苗高生长均随时间呈线性增加;不同品系苗木地径苗高生长差异显著,南林95和湘林80表现最佳。2)滩地最适模式为林-芝麻间作方式,造林密度为4 m×4 m。其经济收益最大,为5417.3元。农林间作3年,造林树种(品系)为杨树湘林80,主伐年龄为10年。3)通过对林木生长影响调查与分析表明:修枝当年(08年)林木树胸径生长速度因修枝的强度而受到抑制,但是在修枝第二年(09年)林木的胸径生长速度因修枝强度而受到促进;修枝当年林木树树高生长速度因修枝的强度而受到促进,但是在修枝第二年林木的树高生长速度因修枝强度而受到一定程度的抑制作用,表现为修枝强度最弱的生长速度表现为最大;其次为强度修枝处理。三块不同修枝强度的标准地中。通过对三块修枝强度林下植物多样性影响调查与分析表明:物种丰富度指数(S)在P1中最大为14。其大小排列顺序为P1>P2>P3;群落均匀度指数(J)在P1中最大为0.77,其大小排列顺序为P1>P3>P2;生态优势度指数(D)在P2中最大,为0.44,其大小排列顺序为P2>P3>P1;和物种多样性指数相比,在P1中表现最大,为2.04,与群落均匀度指数(J)基本上呈相同的变化趋势。三种修枝强度的标准地中各层物种丰富度指数、simpson指数、Shannon-wiene指数、Pielou均匀度指数,物种丰富度指数(S)在P1中最大为14。其大小排列顺序为P1>P2>P3;群落均匀度指数(J)在P1中最大为0.77,其大小排列顺序为P1>P3>P2;生态优势度指数(D)在P2中最大,为0.44,其大小排列顺序为P2>P3>P1;和物种多样性指数相比,在P1中表现最大,为2.04,与群落均匀度指数(J)基本上呈相同的变化趋势。P1只有草本层存在生态优势度指数,说明P1被草本层某一物种控制明显,从前面的重要值来看这一树种就是苍耳; P2、P3与P1情况相似,只有草本层存在生态优势度指数,P2被草本层中苍耳控制明显,P3被草本层苍耳和商陆控制明显。通过对滩地杨树生长和养分研究发现,杨树林土壤全N含量在1.23-1.39g/kg之间,修枝后林地土壤全氮含量降低,但修枝强度过大,影响减弱;全磷、速效磷、钾、钙、镁含量在修枝前后差异不显著(p>0.05)。不同土层深度土壤的全氮、全磷、速效磷含量均以0-10 cm层的含量最大,随土层深度加深而减少,尤其是修枝后全氮和全磷含量下降更快。同一修枝强度下,各种养分含量在不同方向的差异较小,基本持平,只有钙的含量在每个方向都是以轻度修枝最大。植物各器官中,全氮含量以根最高,但三种修枝强度下,随着年龄增大枝的全氮含量降低,根的全氮含量增加。同时,修枝对上部枝的全氮含量影响显著(p<0.05);修枝强度对中部枝和大于5 mm根的全氮含量影响显著(p<0.05)。修枝对植物各组分全磷含量影响不显著(p>0.05);除轻修与强修的中部枝的钙含量有显著差异外(p<0.05),修枝对植物钾、钙、镁的影响不显著(p>0.05),但随着枝的生长钾、钙、镁的含量有降低的趋势;随着根的生长,钾、钙、镁的含量变化规律不明显。更多还原

【Abstract】 Beach is micro-topography which is seasonally flooded river plains. Forest beach plays important role in the manufacture, which effectively relieves the contradiction between people of densely populated. Therefore, it has a important role in national economy. However, unscientific beach use beach use inefficient, which not only destroys the beach but also causes serious environmental problems and ecological disasters. Those ecological environmental problems affect the sustainable development. Beach resources′effective development becomes a pressing problem which need to be solved, forestation model beach of WAN river and short-term effects of pruning poplar are premise and basis of solving this problem.In the course of the study, this paper fully refers study of Chinese forest ecosystem network system“line”and research of demonstration project, absorbs succeed experience of“priority to forests”in Yangtze river and“forestation, snail disease prevention”. The main content of this paper includes three fields: 1) growth pattern and comparative study for different strains of poplar seedlings,2) comparative study of forestation model beach,3) comparative study of different pruning intensity. Have made a preliminary conclusion:1) The growth of seedling height and diameter of four strains of poplar increase linearly with time; the different growth of diameter and height is conspicuous in different strains, south forest 95 and Xianglin 80 are optimal.2) The mode of forest-sesame is the best mode, its density is 4m×4m. Its economic benefits is the biggest, is 5417.3yuan. The intercropping of agriculture and forestry is three years, the tree species (strain) is poplar 80 Xianglin. The age of felling is ten years.3) Through the growth of investigation and analysis show that: the strength of pruning inhibits the grown rate of tree DBH in pruning year (2008), but the strength of pruning promotes the grown rate of tree DBH in next pruning year. The inhibition and advancement due to the strength of tree DBH grown rate shows that: in the weakest strength of pruning the grown rate is the biggest; secondly, it is the treatment of pruning intensity.The investigation and analysis of influence of the understory plants diversity for three pruning intensity shows that: the maximum of species richness index (S) is 14 in P1. The order is P1>P2>P3; The maximum of community evenness index (J) is 0.77 in P1, The order is P1>P3>P2; The maximum of ecology dominance index (D) is 0.44 in P2, The order is P2>P3>P1; Compared with the maximum of species diversity index which is 2.04 in P1, the community evenness index (J) has the same trend. The maximum of species richness index is 14 during the species richness index、simpson index、Shannon-wiene index、pielou uniformity index in the normal land of three pruning intensity. The order is P1>P2>P3; The maximum of community evenness index (J) is 0.77 in P1, The order is P1>P3>P2; The maximum of ecology dominance index (D) is 0.44 in P2, The order is P2>P3>P1; Compared with the maximum of species diversity index which is 2.04 in P1, the community evenness index (J) has the same trend. Only the existence of herb layer has the ecology dominance index in P1, it shows that P1 is obviously controlled by a species of herb layer. We found that it is xanthium through the important value in the front part; P2、P3 is similar with P1, only the existence of herb layer has the ecology dominance index, P2 is obviously controlled by xanthium of herb layer, P3 is obviously controlled by xanthium and phytolacca of herb layer.Through the study of poplar growth and nutrient we can find that total N content is between 1.23~1.39g/kg in poplar forest soil, Nitrogen decreased after pruning in woodland soil. But excessive pruning intensity could reduce the influence; the content of total phosphorus、available phosphorus、potassium、calcium、magnesium has not significant difference before and after pruning(p>0.05). The content of total nitrogen、total phosphorus and available phosphorus in different soil of soil depth is the biggest in 0-10cm layer, decreased with soil depth get deeper, especially, total nitrogen and total phosphorus decreased faster after pruning. Under the same intensity of pruning all kinds of content of nutrient has little difference in different directions, basically flat, only the content of calcium is the biggest by light pruning in every direction.The root contains the largest nitrogen in the plant organ. But under three kinds of pruning strength, the content of total nitrogen get lower along with the growing age and the content of total nitrogen get higher in the root. At the same time, the content of total nitrogen which is in upper branch is obviously affected by pruning (p<0.05); the content of total nitrogen which is in central branch and more than 5 mm length is obviously affected by pruning (p<0.05). The content of total phosphorus which is in every plant components is not obviously affected by pruning (p>0.05); besides the content of total calcium which is in central branch is obviously affected by light pruning and strong pruning (p<0.05), the content of potassium、calcium and magnesium is not obviously affected by pruning (p>0.05), but along with the growing of the branch, the content of potassium、calcium and magnesium tend to decrease; Along with the growing of the root, the content of potassium、calcium and magnesium does not change significantly.更多还原