哈尔滨市主要城市绿地特征和耦合关系

采用样方法调查了哈尔滨市17块绿地的植物多样性,研究城市绿地生态系统中本土植物多样性对外来植物的影响规律。结果如下:哈尔滨市绿地有75种外来植物,外来栽培植物42种,外来非栽培植物33种。在哈尔滨市绿地植物群落中,外来栽培植物的平均盖度、平均重要值和平均出现频度均较高;外来非栽培种的平均盖度、平均重要值较低,而平均出现频度较高。绿地本土植物物种数与外来栽培种、外来非栽培种的物种数极显著正相关(P<0.01),与外来非栽培种的平均出现频度显著负相关(P<0.05)。绿地乔木层本土植物的香农威尔指数、物种丰富度与外来栽培种、外来非栽培种的物种数均显著负相关(P<0.05),乔木层本土植物的均匀度与外来非栽培种的平均出现频度极显著负相关(P<0.01);灌木层本土植物的物种丰富度与外来栽培种的平均重要值显著负相关(P<0.05);草本层本土植物的均匀度与外来非栽培种的平均相对盖度显著正相关(P<0.05)。随绿地总面积的增加,外来栽培种和外来非栽培种的物种数增加,平均出现频度均呈现显著降低的趋势。随建成时间增加,外来栽培种的平均出现频度呈非线形变化,外来非栽培种的平均出现频度呈现降低的趋势。应提高哈尔滨市绿地本土植物的多样性,严格控制新建成的、总面积较小的绿地中外来植物的引种栽培管理,以防止外来植物发展成为危害本地生态系统的入侵植物。

Characteristics and Coupling Relations of Green Space in Major Areas of Harbin

The plant diversity of 17 green spaces in Harbin was investigated by sample method, and the influence of native plant diversity on alien plants in urban green space ecosystem was studied. There are 75 alien plants, 42 alien cultivated plants and 33 alien non-cultivated plants in green space of Harbin. In the greenbelt plant community of Harbin, the average coverage, average importance and average frequency of exotic cultivated plants are higher, while the average coverage and average importance of exotic non-cultivated species are lower, but the average frequency of exotic non-cultivated species is higher. The number of native plant species was positively correlated with the number of exotic cultivated species and exotic non-cultivated species(P<0.01), and negatively correlated with the average frequency of exotic non-cultivated species(P<0.05). The Shannon-Will index and species richness of native plants in the arbor layer of green space were negatively correlated with the number of alien cultivated species and non-cultivated species(P<0.05). The homogeneity of native plants in the arbor layer was negatively correlated with the average frequency of non-cultivated species(P<0.01). The species richness of native plants in the shrub layer was negatively correlated with the average importance of exotic cultivated species(P<0.05); the evenness of native plants in herbaceous layer was positively correlated with the average relative coverage of non-cultivated species(P<0.05). With the increase of the total area of green space, the number of exotic cultivated species and exotic non-cultivated species increased, and the average frequency decreased significantly. With the increase of construction time, the average frequency of exotic cultivated species did not change linearly, while the average frequency of exotic non-cultivated species showed a decreasing trend. We should improve the diversity of native plants in Harbin green space, strictly control the introduction and cultivation management of alien plants in newly built green space with a small total area, in order to prevent the development of alien plants into invasive plants that endanger the local ecosystem.