A Study On The Historical Changes And Current Strategies Of Aquatic Plants In The Summer Palace

The Summer Palace,formerly known as the Qingyi Garden,is one of the largest and bestpreserved royal gardens in the world.The plant landscape in it is an important part of the historical and cultural heritage.Its cultural and landscape value cannot be ignored,and the aquatic plant landscape also occupies a large proportion.From the tourist attraction in Jin and Yuan Dynasties to its opening as a park,the Summer Palace has undergone different historical periods.The aquatic plant landscape has also changed,with problems such as loss of historical authenticity,excessive planting density,and eutrophication of local water bodies.I studied the historical changes of the aquatic plants by reading ancient and modern literature(local history,poetry and articles,government reports,archives,scientific research reports),and referred to materials such as inscribed boards,couplets,and historical images of the garden.Meanwhile,I surveyed the current aquatic plants in the Summer Palace through field surveying,photographing and recording,and obtained results on the species and distribution of aquatic plants in the Summer Palace.Based on the results,the historical landscape of the aquatic plants is compared with the current plant landscape,and the similarities and differences between the ancient and the modern landscape are analyzed.This study puts forward further maintenance and improvement strategies for similar aquatic plant landscapes while proposing to transform different ones.The optimal design of the aquatic plant planting design at the local nodes of the Summer Palace is also proposed,so that it can provide a reasonable reference for restoring its historical authenticity,adjusting,and improving the overall landscape effect of the Summer Palace.The main conclusions are as follows:(1)Before the Qingyi Garden was built,the research area had the most abundant aquatic plants.By the Ming Dynasty,it had developed into a landscape of aquatic plants with ornamental,practical,cultural,and ecological functions.Water caltrop(Trapa bispinosa),Gorgon Fruit(Euryale ferox)and arrowhead(Sagittaria trifolia var.sinensis)for medicinal and edible purposes were no longer widely cultivated afer this period.(2)During the period of Qingyi Garden,aquatic plants were both ornamental and practical,and had a deeper cultural mood due to the combination with surrounding scenic spots and buildings,forming unique thematic landscapes.The rural scenery and the royal and magnificent scenery were integrated by plants.The embellishments of the landscape complement each other.(3)During the period of the Summer Palace,the number of aquatic plants was greatly reduced.The aquatic plant landscape was transformed into a lotus(Trapa bispinosa)-based landscape.In addition to the well-maintained Iinner Lake area,the rest of the water of the garden were deserted in the late Qing Dynasty;the rice landscape was annihilated with history.The mooring gradually changed from soft to hard,so plants such as radix angelicae(Angelica dahurica),smartweed(Polygonum orientale),and pampas grass(Cortaderia selloana)gradually disappeared.(4)The current aquatic plant landscape in the Summer Palace is still dominated by lotus.The reeds(Phragmites australis)and cattails(Typha orientalis)are mainly planted along the shoreline,and the lythrum(Lythrum salicaria)and are water onions(Scirpus validus)planted in some areas.Compared with ancient times,plant species such as lythrum,water onionss,calamus(Acorus calamus),and yellow calamus(Iris pseudacorus)are added.Aquatic plants are mainly used for ornamental.(5)Most of the current aquatic plant species and landscape features in the Summer Palace do not match the ones in the Qingyi Garden period.The lotus takes up too much space in the water area,the aquatic plant landscape richness is low,and the ornamental effect is not good.(6)On the basis of meeting the needs of contemporary people for landscape,it is recommended to restore the aquatic plant landscape in the Qingyi Garden period properly,reduce the plants with poor current landscape effects,give full play to the landscape value of various attractions and buildings in the garden,rebuild the aquatic plant community,improve the quality of the ecological environment of waters and achieve sustainable development.