不同土地利用类型下河岸带草本植物群落结构及其影响因素
发布时间：2018-12-11 02:10
【摘要】：河岸带作为流域景观中一个重要的地理单元,是河流生态系统与陆地生态系统连接的重要纽带,其特殊的生境使其具有明显的边缘效应,能为各种生物提供栖息地,并具有较高的生物多样性。随着农业、城镇化的发展以及人为干扰影响的增强,河岸带植被,尤其是草本植物的退化和消失现象明显。而土地利用与河岸带物种多样性密切相关,因此研究人为活动下植物群落结构及其影响因素有助于进一步了解人类对河岸带生态系统的干扰程度,为河岸带植物群落结构的保护与管理提供理论依据。本研究分别于2012年、2014年对太湖流域三条入湖河流在不同土地利用类型(林地、农田、村镇)相邻的自然河岸带草本植物群落结构进行了调查,同时于2014年1月(冬季)、4月(春季)、8月(夏季)采集了三个不同时期河岸带的土壤样品,进行室内幼苗萌发实验研究种子库的动态变化。通过土壤种子库与地表物种数的相似性研究,探讨了土壤种子库对河岸带群落结构的影响,通过河岸带草本植物物种多样性与环境因子关系,解析环境因素对草本植物群落结构的影响。本研究得到以下主要结论如下：(1)对2014年地表植物进行调查,发现不同土地利用类型下,河岸带草本植物共有有23科50属55种,其中以一年生禾本科和菊科植物为主。不同土地利用下草本植物物种数的大小关系分别为村镇(44)农田(34)林地(33)。(2)比较2012年与2014年河岸带草本植物的物种数,发现两年的相同物种数仅为29种,占各自总物种数的58%和53%。物种组成上来看,2012年林地、农田、村镇的物种数分别为28种、40种、40种；2014年林地、农田、村镇的物种数分别为为33种、34种、44种；一年生草本植物在不同年际中均占有优势地位,其中2014年一年生植物物种高于2012年,而多年生植物在两年时间内稳定变化；同时,部分在2012年存在的物种,2014年已经消失,并有了新物种的替代。(3)研究不同土地利用类型下河岸带土壤种子库的季节变化,结果表明：三个季节,共萌发21科54属59种草本植物,从生活型来看,一年生草本植物在土壤种子库萌发物种中占总物种数的64%,而多年生草本植物则占总物种数的19%。从物种组成上来看,冬季、春季、夏季的萌发数分别为33种、44种、40种。河岸带土壤种子库物种较地上植被物种更加丰富。此外,春季土壤种子库储量较夏季和冬季大,为21532.9±8798.9粒/m2,且农田的种子库储量高于林地和村镇。同时,不同季节土壤种子库的物种多样性表现为：冬季受人为干扰影响较弱,林地的种子库物种多样性高于农田和村镇,而春季和夏季,林地的物种多样性显著低于农田和村镇。(4)分析不同土地类型下河岸带土壤种子库的空间垂直变化,发现河岸带土壤种子库在0-15cm土层均有不同的分布,且大多呈随着土层深度的加深,不同土地利用下土壤种子库储量、物种组成以及物种多样性逐渐下降的规律。另外,由于不同季节的干扰程度不同,土壤种子库在农田和村镇的变化差异也不断发生,干扰严重的季节,种子向下层移动明显。(5)河岸带土壤种子库与地表植物的共同物种有38种,且种子库萌发的物种数多于地表植物的物种数,仅在土壤种子库种出现的物种数有21种,而仅在地表植物出现的有17种,物种相似性为0.667。不同的生活型、不同土地利用类型下种子库与地表植物物种的相似性集中在60%-80%,相似性较高。表明该土壤种子库对河岸带群落结构的恢复有重要的作用。(6)对河岸带草本植物群落结构及其环境因子响应的模拟,发现不同土地利用类型、河岸带的坡向以及土壤pH值均会影响地表植物物种丰富度。阳坡的物种丰富度高于阴坡；下游为林地的土地利用下,pH值较高,物种数居中,而农田土地利用下pH值最低,物种数也相应降低。河岸带受水体影响较大,种子向下移动,在下游为林地的土地利用类型下物种数较高；村镇不同河流段的物种数有显著性差异,可能是受人为干扰程度不同而导致的。
[Abstract]:The riparian zone, as an important geographical unit in the landscape of the river basin, is an important link between the river ecosystem and the terrestrial ecosystem, and its special habitat has obvious edge effect, can provide habitat for various organisms, and has higher biological diversity. With the development of agriculture and urbanization and the increase of the influence of man-made interference, the vegetation of the riparian zone, especially the degradation and disappearance of the herbaceous plants, is obvious. Land use is closely related to the species diversity of the riparian zone, so the study of the plant community structure and its influencing factors in the study of man-made activities can help to understand the extent of the disturbance of the human to the riparian zone ecosystem, and provide the theoretical basis for the protection and management of the plant community structure of the riparian zone. The study of the community structure of the natural river banks with different land use types (forestland, farmland, and town) in the Taihu basin in 2012 and 2014 was investigated, and in January 2014 (winter), April (spring), In August (summer), three soil samples with different riparian bands were collected, and the dynamic changes of the seed bank were studied. The effect of soil seed bank on the community structure of the riparian zone was studied by the similarity of the soil seed bank and the surface species number, and the effect of environmental factors on the structure of the herb community was analyzed through the relationship between the species diversity and the environmental factors of the river bank. The main conclusions of this study are as follows: (1) There are 55 species of 50 genera of 23 families in the river bank with different land use types under different land use types, including annual Gramineae and Compositae plants. The size relation of the number of the herb species under different land use is the farmland (34) and the forest land (33) of the village (44), respectively. (2) The number of species of herbaceous plants in the riparian band in 2012 and 2014 was compared, and the number of the same species in two years was found to be only 29 species, accounting for 58% and 53% of the total species. On the basis of species composition, the number of species of forest land, farmland and town in 2012 is 28 species, 40 species and 40 species, respectively. The number of species in forest land, farmland and town in 2014 is 33 species, 34 species and 44 species, respectively. Of these, the annual plant species in 2014 were higher than in 2012 and the perennial plants were stable over the last two years; at the same time, some of the species present in 2012 have disappeared in 2014 and have been replaced by new species. (3) The seasonal variation of the soil seed bank of the riparian zone under different land use types was studied. The results showed that, in the three seasons, there were 59 species of 54 genera of the 21 families, and the annual herb accounted for 64% of the total species in the soil seed bank. and the perennial herbs account for 19% of the total species. From the species composition, the number of germination in winter, spring and summer is 33 species, 44 species and 40 species, respectively. The species of the soil seed bank in the riparian zone is richer than that on the ground. in addition, that reserve of the soil seed bank in spring is great in the sum of summer and winter, and is 21532.9-87998. 9/ m2, and the storage of the seed bank in the field is higher than that of the forestland and the village. At the same time, the species diversity of the soil seed bank in different seasons is as follows: the winter is affected by man-made interference, the diversity of the seed bank of the forest land is higher than that of the farmland and the town, and the species diversity of the forest land is obviously lower than that of the farmland and the village in the spring and the summer. (4) analyzing the spatial vertical change of the soil seed bank of the riparian zone under different land types, and finding that the soil seed bank of the riparian zone has different distribution in the 0-15cm soil layer, Species composition and the gradual decline of species diversity. In addition, due to the different degree of interference in different seasons, the variation of the soil seed bank in the farmland and the village and the village is also taking place, and the seeds move to the lower layer obviously during the severe season. (5) There are 38 species of the soil seed bank and the surface plant in the riparian zone, and the number of species in the seed bank is more than that of the surface plants, and there are only 21 species in the soil seed bank, and only 17 species are present in the surface plants, and the species similarity is 0. 667. The similarity of the seed bank and the surface plant species in different land-use types is in the range of 60% -80% and the similarity is high. It is shown that the soil seed bank plays an important role in the restoration of the community structure of the riparian zone. (6) The structure of the plant community and the response of the environmental factors of the plant community in the riparian zone were simulated, and different land use types, the slope of the riparian zone and the soil pH were found to affect the richness of the plant species on the surface. The species richness of the male slope is higher than that of the negative slope; in the land use of the forest land downstream, the pH value is higher and the number of species is the middle, and the pH value of the land use of the farmland is the lowest, and the number of species is correspondingly reduced. The water of the riparian zone is affected by the water body, the seeds move downwards, and the species number is higher at the lower reaches of the land use type of the forest land; the species number of the different river sections of the villages and towns has a significant difference, which can be caused by the difference of the man-made interference degree.
【学位授予单位】：南京大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：Q948
本文编号：2371662
[Abstract]:The riparian zone, as an important geographical unit in the landscape of the river basin, is an important link between the river ecosystem and the terrestrial ecosystem, and its special habitat has obvious edge effect, can provide habitat for various organisms, and has higher biological diversity. With the development of agriculture and urbanization and the increase of the influence of man-made interference, the vegetation of the riparian zone, especially the degradation and disappearance of the herbaceous plants, is obvious. Land use is closely related to the species diversity of the riparian zone, so the study of the plant community structure and its influencing factors in the study of man-made activities can help to understand the extent of the disturbance of the human to the riparian zone ecosystem, and provide the theoretical basis for the protection and management of the plant community structure of the riparian zone. The study of the community structure of the natural river banks with different land use types (forestland, farmland, and town) in the Taihu basin in 2012 and 2014 was investigated, and in January 2014 (winter), April (spring), In August (summer), three soil samples with different riparian bands were collected, and the dynamic changes of the seed bank were studied. The effect of soil seed bank on the community structure of the riparian zone was studied by the similarity of the soil seed bank and the surface species number, and the effect of environmental factors on the structure of the herb community was analyzed through the relationship between the species diversity and the environmental factors of the river bank. The main conclusions of this study are as follows: (1) There are 55 species of 50 genera of 23 families in the river bank with different land use types under different land use types, including annual Gramineae and Compositae plants. The size relation of the number of the herb species under different land use is the farmland (34) and the forest land (33) of the village (44), respectively. (2) The number of species of herbaceous plants in the riparian band in 2012 and 2014 was compared, and the number of the same species in two years was found to be only 29 species, accounting for 58% and 53% of the total species. On the basis of species composition, the number of species of forest land, farmland and town in 2012 is 28 species, 40 species and 40 species, respectively. The number of species in forest land, farmland and town in 2014 is 33 species, 34 species and 44 species, respectively. Of these, the annual plant species in 2014 were higher than in 2012 and the perennial plants were stable over the last two years; at the same time, some of the species present in 2012 have disappeared in 2014 and have been replaced by new species. (3) The seasonal variation of the soil seed bank of the riparian zone under different land use types was studied. The results showed that, in the three seasons, there were 59 species of 54 genera of the 21 families, and the annual herb accounted for 64% of the total species in the soil seed bank. and the perennial herbs account for 19% of the total species. From the species composition, the number of germination in winter, spring and summer is 33 species, 44 species and 40 species, respectively. The species of the soil seed bank in the riparian zone is richer than that on the ground. in addition, that reserve of the soil seed bank in spring is great in the sum of summer and winter, and is 21532.9-87998. 9/ m2, and the storage of the seed bank in the field is higher than that of the forestland and the village. At the same time, the species diversity of the soil seed bank in different seasons is as follows: the winter is affected by man-made interference, the diversity of the seed bank of the forest land is higher than that of the farmland and the town, and the species diversity of the forest land is obviously lower than that of the farmland and the village in the spring and the summer. (4) analyzing the spatial vertical change of the soil seed bank of the riparian zone under different land types, and finding that the soil seed bank of the riparian zone has different distribution in the 0-15cm soil layer, Species composition and the gradual decline of species diversity. In addition, due to the different degree of interference in different seasons, the variation of the soil seed bank in the farmland and the village and the village is also taking place, and the seeds move to the lower layer obviously during the severe season. (5) There are 38 species of the soil seed bank and the surface plant in the riparian zone, and the number of species in the seed bank is more than that of the surface plants, and there are only 21 species in the soil seed bank, and only 17 species are present in the surface plants, and the species similarity is 0. 667. The similarity of the seed bank and the surface plant species in different land-use types is in the range of 60% -80% and the similarity is high. It is shown that the soil seed bank plays an important role in the restoration of the community structure of the riparian zone. (6) The structure of the plant community and the response of the environmental factors of the plant community in the riparian zone were simulated, and different land use types, the slope of the riparian zone and the soil pH were found to affect the richness of the plant species on the surface. The species richness of the male slope is higher than that of the negative slope; in the land use of the forest land downstream, the pH value is higher and the number of species is the middle, and the pH value of the land use of the farmland is the lowest, and the number of species is correspondingly reduced. The water of the riparian zone is affected by the water body, the seeds move downwards, and the species number is higher at the lower reaches of the land use type of the forest land; the species number of the different river sections of the villages and towns has a significant difference, which can be caused by the difference of the man-made interference degree.
【学位授予单位】：南京大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：Q948
【参考文献】
相关期刊论文 前1条
1 刘华;蒋齐;王占军;潘占兵;;不同封育年限宁夏荒漠草原土壤种子库研究[J];水土保持研究;2011年05期
，本文编号：2371662
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