辽东山区三种林型土壤动物群落特征及其在凋落物分解中的作用研究

发布时间：2018-06-19 07:34

本文选题：土壤动物 + 森林类型　；参考：《河北农业大学》2015年硕士论文

【摘要】：我国次生林面积约占森林总面积的55%,东北地区高达60%以上,为满足人们对木材的需求,落叶松人工林的面积在次生林生态系统中逐渐增加,形成了人工林与次生林镶嵌的景观结构,但是落叶松人工林取代次生林出现了许多问题,地力衰退尤为突出,凋落物分解受阻是重要原因之一,土壤动物通过取食或刺激土壤微生物活性调控凋落物分解和养分释放,是影响凋落物分解的主导因素之一,明确土壤动物的群落结构及其对不同凋落物分解的贡献,是解决地力衰退的基础。本文以辽东山区天然阔叶次生林、落叶松人工林、落叶松林下阔叶树种天然更新形成的混交林为研究对象,调查了3种林型土壤动物群落组成;采用凋落物袋法对林分内自然凋落物(阔叶凋落物、针叶凋落物和针阔混合凋落物)进行了原位分解和交互分解试验;利用不同孔径凋落物袋控制参与凋落物分解的土壤动物,并对其进行分类统计。通过方差分析、主成分分析(PCA)以及冗余分析(RDA)等分析方法,分析研究了3种林型内土壤动物群落结构的差异及其与环境因子间关系,探讨了土壤动物在自然凋落物分解和养分释放过程中的作用,主要结果如下:(1)辽东山区3种林型共获得中小型土壤动物102667只,属于3门10纲,90个类群,甲螨亚目、等节跳科、疣跳科和棘跳科为优势类群,中气门亚目、前气门亚目、鳞跳科、颤蚓目、长角跳科、短角亚目幼虫和长角亚目幼虫为常见类群,该地区中小型土壤动物个体密度变化范围是7.55×10~3~6.45×10~4ind·m~(-2);水平分布上,落叶松人工林中小型土壤动物个体密度最高,垂直分布上,中小型土壤动物具有较明显的表聚性。重复度量方差分析表明,季节对个体密度、类群、各多样性特征指数、捕食性类群个体密度、腐食性类群个体密度和植食性类群个体密度有显著性影响(P0.05),取样层次对个体密度、类群、多样性特征指数、腐食性类群个体密度和植食性类群个体密度有显著性影响(P0.05),林型对类群和各多样性特征指数有显著性影响(P0.05)。通过环境因子与中小型土壤动物群落的冗余分析(RDA)可知,凋落物层中小型土壤动物群落结构主要受凋落物的p H值和凋落物层含水率影响(P0.05),而土壤层土壤动物群落受土壤p H值、土壤含水率和土壤有机质含量影响显著(P0.05)。(2)获得大型土壤动物4046只,属于3门8纲,71个类群,总生物量为454.32g,优势类群为正蚓目、颤蚓目和地蜈蚣目,常见类群为漏斗蛛科、金龟总科幼虫、隐翅甲科、短角亚目幼虫、倍足纲马陆目和长角亚目幼虫。该地区大型土壤动物的个体密度变化范围是30.37~164.44ind·m~(-2),生物量变化范围是2.29~25.47g·m~(-2)。重复测量方差分析表明,季节对大型土壤动物个体密度、类群数、总生物量、蚯蚓生物量、各多样性特征指数、捕食性类群个体密度、腐食性类群个体密度和植食性类群个体密度影响显著(P0.05),取样层次对个体密度、类群数、总生物量、蚯蚓生物量、各多样性特征指数和腐食性类群个体密度影响显著(P0.05),林型对类群数和各多样性指数影响显著(P0.05)。通过大型土壤动物群落与各环境因子的冗余分析显示,该地区凋落物含水率、厚度、p H值和全C含量是影响凋落物层大型土壤动物分布的重要因子(P0.05),土壤全C、全N和有机质是影响土壤层大型土壤动物群落分布的重要因子(P0.05)。(3)经过1年自然分解,5mm孔径凋落物袋中阔叶凋落物、针阔混合凋落物和针叶凋落物在3种林型中损失率分别为50.42%、53.83%和33.92%,根据Olson衰减模型计算,3种凋落物分解的周转期分别为4.34~8.88年,3.92~6.49年和8.61~10.95年。3种凋落物在分解期间表现出较明显的阶段性,水热条件好的盛夏至初秋时节分解速率高于初冬至春末夏初时节;各凋落物分解过程中,C元素含量呈下降趋势,表明C元素一直在释放,而N和P的含量呈现明显的波动,表明N和P有明显的富集,并且在分解过程中以富集为主,C/N则一直呈现下降趋势。(4)在第1年分解过程中,参与凋落物分解的土壤动物类群主要有甲螨亚目、等节跳科、中气门亚目、棘跳科、疣跳科、颤蚓目、鳞跳科、长角亚目幼虫、短角亚目幼虫和长角跳科,以腐食性类群为主,通过主成份分析(PCA),针叶凋落物与阔叶凋落物和针阔混合凋落物中的土壤动物群落有较大差异,特别是在8月,并且这种差别主要体现在个体密度上。(5)通过不同孔径凋落物袋控制参与凋落物分解的土壤动物类群进行3种凋落物野外试验,分解1年后,土壤动物对阔叶凋落物分解贡献率为24.75%,其中大型土壤动物贡献率为7.40%,中小型土壤动物贡献率为17.35%,土壤动物对针阔混合凋落物分解贡献率为22.36%,大型土壤动物贡献率为7.51%,中小型土壤动物贡献率为14.85%,土壤动物对针叶凋落物分解贡献率为11.05%,大型土壤动物的贡献率为3.25%,中小型土壤动物的贡献率为7.80%。土壤动物对不同凋落物分解和养分元素释放促进作用不同,分解过程中中小型土壤动物的作用大于大型土壤动物的作用,中小型土壤动物对3种凋落物的分解主要表现为促进作用,对阔叶凋落物和针阔混合凋落物的促进作用较大,而对针叶凋落物的促进作用相对较小,并且中小型土壤动物的作用从5月至10月先增加后降低,大型土壤动物的作用则未表现出规律性,并且一些时间段大型土壤动物可能对凋落物分解具有抑制作用。土壤动物对C元素的释放促进作用较明显,而对N和P元素更多表现出了抑制作用。
[Abstract]:The area of secondary forest in China accounts for about 55% of the total forest area, and more than 60% in the northeast to meet the demand for wood. The area of the larch plantation is gradually increased in the secondary forest ecosystem, forming a mosaic structure of artificial forests and secondary forests, but the replacement of secondary forest with larch plantation has many problems. One of the important reasons for the decline of the litter is that the litter decomposition is one of the important reasons. Soil animals regulate litter decomposition and nutrient release by feeding or stimulating soil microbial activity. It is one of the leading factors affecting litter decomposition. The community structure of soil animals and their contribution to the decomposition of different litter are the basis for solving the decline of the soil. In this paper, the natural broadleaved forest in Liaodong mountain area, the larch plantation and the mixed forest of the natural regeneration of the deciduous broad-leaved tree species under the larch forest as the research object, 3 kinds of forest type soil animal community composition were investigated, and the litter bag method was used to carry out the natural litter in the stand (broad leaf litter, coniferous litter and coniferous and broad-leaved litter). In situ decomposition and interaction decomposition test, the soil animals involved in litter decomposition were controlled by different aperture litter bags and classified. By analysis of variance analysis, principal component analysis (PCA) and redundancy analysis (RDA), the differences of soil animal community structure in the 3 forest types and their environmental factors were analyzed and studied. The effects of soil fauna on decomposition and nutrient release of natural litter are discussed. The main results are as follows: (1) 102667 middle and small soil animals were obtained from 3 forest types in Liaodong mountain area, belonging to 3 gate 10 classes, 90 groups, mite suborders, and eanthaceas, and the wart and eanthotaxis were dominant groups, middle Qi gate suborder, anterior suborder suborder, scaly jump. The vermiculdae, the vermiculdae, the long horned family, the short horned larva and the long horned suborder larva are common groups. The variation range of the individual density of small and medium soil animals in this area is 7.55 x 10~3~6.45 x 10~4ind. M~ (-2), and the individual density of the small soil animals in the larch plantation is the highest in the horizontal distribution, and the small and medium soil animals are more obvious in the vertical distribution. The analysis of repeated measures of variance showed that season has a significant influence on individual density, group, diversity characteristic index, individual density of predatory groups, individual density of predatory groups and individual density of herbivorous groups (P0.05), sampling level on individual density, group, diversity characteristic index, individual density and planting of humic groups. There was a significant influence on the individual density of the diet group (P0.05), and the forest type had a significant influence on the group and the diversity index (P0.05). Through the environmental factors and the redundancy analysis of the small and medium soil animal communities (RDA), it was found that the structure of the small and medium soil animal communities in the litter layer was mainly influenced by the P H value of litter and the water content of litter layer (P0. 05), the soil layer soil animal community is affected by soil P H value, soil moisture content and soil organic matter content significantly (P0.05). (2) 4046 large soil animals are obtained, belonging to 3 8 classes, 71 groups, the total biomass is 454.32g, the dominant groups are vermis, vermis and ground centipede, common groups are funnel arachnoid, larva of Tortoise Tortoise Tortoise, cryptowing Larva of family armydifamily, short horned suborder, dippod and larva. The variation range of the individual density of large soil animals in this area is 30.37~164.44ind. M~ (-2), and the range of biomass is 2.29~25.47g. M~ (-2). Repeated measurements of variance analysis show that the individual density, group number, total biomass, earthworm life of large soil animals in the season The individual density of predatory groups, individual density of predatory groups, individual density of predatory groups and individual density of phytophagous groups were significantly affected (P0.05). Sampling levels had significant influence on individual density, group number, total biomass, earthworm biomass, diversity index and individual density of herbivorous groups (P0.05). The diversity index has a significant impact (P0.05). Through the redundancy analysis of large soil animal communities and environmental factors, the water content of litter, thickness, P H value and total C content in this area are important factors affecting the distribution of large soil animals in the litter layer (P0.05). The whole soil C, full N and organic matter are the factors affecting the large soil animal community in the soil layer. The important factor of cloth (P0.05). (3) after 1 years of natural decomposition, the loss rates of broadleaf litter in the 5mm aperture litter bag, the coniferous and broad-leaved litter and the coniferous litter in the 3 forest types were 50.42%, 53.83% and 33.92% respectively. According to the Olson attenuation model, the turnover period of 3 litter decomposition was 4.34~8.88 years, 3.92~6.49 and 8.61~10.95 years respectively. The decomposition of.3 species showed a distinct stage during the decomposition period. The decomposition rate of the warm summer to early autumn was higher than that in the early winter to the early summer and early summer in the early autumn. The content of C elements showed a downward trend during the litter decomposition process, indicating that the C elements had been released, while the content of N and P showed obvious fluctuations, indicating that N and P had obvious enrichment. (4) during the first year decomposition process, the soil animal groups involved in litter decomposition were mainly the methodea, the middle gas gate suborder, the eanthodiptera, the verrucinia, the vermis, the larva of the long horned suborder, the short horned larva and the long horned hopefamily in the first year decomposition process. The group is dominated by the principal component analysis (PCA). There are great differences in the soil animal communities in the coniferous litter and the broad leaf litter and the coniferous and broad-leaved mixed litter, especially in August, and this difference is mainly reflected in the individual density. (5) 3 species of soil fauna, which are involved in litter decomposition by different pore litter bags, are carried out. After 1 years of field test, the contribution rate of soil fauna to broadleaf litter decomposition was 24.75%, of which the contribution rate of large soil animals was 7.40%, the contribution rate of small and medium soil animals was 17.35%, the contribution rate of soil animal to the mixed litter decomposition was 22.36%, the contribution rate of large soil animals was 7.51%, and the contribution rate of small and medium soil animals. 14.85%, the contribution rate of soil fauna to coniferous litter decomposition was 11.05%, the contribution rate of large soil animals was 3.25%. The contribution rate of small and medium soil animals was 7.80%. soil animals to promote different litter decomposition and nutrient element release, and the effect of small and medium soil animals in the process of decomposition was greater than that of large soil animals. The decomposition of the 3 species of litter was mainly promoted by the small and medium soil animals, which played a greater role in promoting broadleaf litter and coniferous and broad-leaved litter, while the promotion of coniferous litter was relatively small, and the role of small and medium soil animals increased from May to October, and the effect of large soil animals was not apparent. Regularity, and some time periods of large soil animals may inhibit the decomposition of litter. The release of soil animals on the release of C elements is more obvious, and more inhibition of N and P elements.
【学位授予单位】：河北农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S714

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