| The conservation of urban biodiversity is an important part of the global biodiversity agenda,as cities are centres of human activity.Forest ecosystems provide a range of ecological functions,such as carbon storage and oxygen release,which help to minimise the adverse effects of urbanisation and improve the natural environment.The unique perspective of studying natural forests shows the full potential of a sustainable approach to studying nature and exploring nature-based solutions.Landscape plant communities must be designed in accordance with nature and follow the laws of natural development.Our research is essential for managing forests to reduce ecological problems in cities and for predicting the impact of anthropogenic influences on the flow of carbon between forests and the atmosphere.This study explores the above-ground biomass and biodiversity dependence of each upper and lower forest layer in a warm temperate deciduous broad-leaved forest based on data from a large sample of 20hm~2 forest monitoring plots in the Dongling Mountains,laying the foundation for a holistic understanding of forest plant community biomass stocks and the factors influencing them,and for regional vegetation carbon assessment.The main results are as follows.(1)Taking the 20 hm~2 forest of Dongling Mountain as the research object and landscape ecology as the entry point,we elaborate on the principles of landscape ecology contained and embodied in landscape gardens,and analyse in depth the important role of the application of ecological principles in landscape gardens,in urban construction,learning the natural ecological and rational allocation of trees,shrubs,vines and grasses in a community,forming a composite hierarchy and beautiful seasonal landscape,with plants of different ecological characteristics in their respective places.The plants with different ecological characteristics each have their own place and form a stable community.It also attempts to propose specific strategies to strengthen the effectiv e application of landscape ecology in landscape gardening from three aspects: greening design,plant maintenance and pest control,so that the outstanding advantages of ecological principles can be given full play.(2)The top ten important values in the understorey are 20.13%,10.20%,10.10%,8.81%,5.88%,5.61%,3.66%,3.34%,3.27%,3.10% for Cinquefoil,Hexadoxylum,Hazelnut,Liaodong oak,Flowering willow,Black birch,Mountain poplar,Small-flowered insignia and Beijing rowan respectively.The number of these species accounted for 74.10% of the significant value of the number of species in the lower forest.In terms of species multiplicity,the highest number of individuals in the entire lower forest was Cinquefoil,with 10,319 plants,accounting for 24.46% of the number of plants in the lower forest.In terms of above-ground biomass,the lower forest biomass was mainly concentrated in Cinquefoil,followed by Hairy Clove.(3)The top ten important values in the upper forest were 33.10%,17.47%,9.64%,6.95%,6.85%,5.29%,3.08%,2.58%,2.47% and 1.95% for Liaodong oak,black birch,five-horned maple,mountain poplar,white birch,walnut rowan,Peking rowan,Mongolian linden,flowering willow and spring elm respectively,and the number of these species in the upper forest accounted for 89.39% of the significant values for the number of species in the upper forest.In terms of species multiplicity,the highest number of individuals in the entire upper forest was Liaodong oak with 3785 plants,accounting for 37.20% of the number of plants in the lower forest.In terms of aboveground biomass,the biomass of the upper forest was mainly concentrated in Liaodong oak,followed by five-horned maple.(4)There were direct positive effects of species richness in the upper forest(β=0.11,P=0.004),stand density in the upper forest(β=0.10,P=0.005),species richness in the understory(β=0.09,P=0.006)and stand density in the understory(β=0.53,P=0.000)on understory biomass.There was a direct negative effect of above-storey biomass(β=0.20,P<0.001)and soil nutrients(β=0.22,P<0.001)on understorey biomass.Soil nutrients(β=0.18,P<0.001)and above-forest stand density(β=0.35,P=0.000)had a direct positive effect on above-forest biomass.There was a direct positive effect of understorey species richness(β=0.34,P<0.001)and understorey stand density(β=0.26,P<0.001)on understorey stand density,but in contrast there was no direct effect of understorey stand density on understorey species richness.Soil nutrients(β = 0.38,P <0.001)had a direct positive effect on understorey species richness and soil nutrients(β= 0.22,P < 0.001)also had a direct negative effect on understorey stand density,but soil nutrients had no direct effect on understorey species richness or understorey stand density.There was a direct positive effect of species richness in the understory(β =0.28,P < 0.001),but a direct negative effect of species richness in the understory(β =0.30,P < 0.001)on biomass in the understory.Above-forest biomass(β = 0.24,P <0.001)had a direct negative effect on understorey stand density. |
PDF Full Text Request