I am convinced that the publication of The Return of Rivers will be appreciated by readers，and we will gain inspiration and reference from it.
Original Deputy Director of Shanghai Urban Construction andEnvironmental Protection Commission，the Standing Committee of NPC and original Director General of Shanghai Afforestation AdministrationHu Yunhua2014.12.15
序三
人与天
调而后天下之美生
这是中国古代哲学家管子的一句名言。我欲为之写序的书名叫作《回归的江河》。这个书名打动了我，因为是回归自然，实际上是回归对自然的认知。为什么要“以文会友，与古为徒”呢？因为人类的文化是千秋万代积累而成的，前车之鉴乃后车之师也。中华民族的宇宙观是“天人合一”，“天人之际，合二为一”。人有自然性和社会性的双重性，视宇宙为两元即自然与人，简赅而言即天人，人是天人的合一体。天是君，人为臣。而人的主观能动性表现在“人杰地灵”，对风景园林则表现为“景物因人成胜概”。在上海市政总院成立六十华诞之际，作为上海市政总院中的景观设计研究院以其十年来的工作业绩为总院纪念成立六十周年献礼那是太有意义了。社会上，特别对于学科在实践和理论宝库里增加了这么一笔物质和精神的财富。为此首先要致谢这一群辛勤的园丁。
在引荐、赞赏以外我还想提两个问题来共同探讨。古代水利成功之作都江堰有治水的十字诀刻在石上唯恐失传。前四个字“安流湏轨”，安定水流要提供水流运行的轨道，亦即相应容量的河床。后六个字“深淘滩，低作堰”。河底淤积成滩要深掏以保证足够运行的过水断面积，这样堤就可低作，让市民看得见水。上海地处长江出海口，主要导江入海。因此，水流运行的通畅至关重要。而黄浦江以钢渣填河造陆、长江口崇明岛滩地投巨资作石坝以稳定淤积滩地，都是缩小了河床的容积。统计数字显示长江入海口海平面年升高值大于世界平均值。长江口河面聚集物漂流不易散，崇明岛湿地公园建成后候鸟的数量和候鸟品种的数量呈持续递减形势发展。森林、海洋、湿地是世界三大自然资源，是不可人造的，湿地是候鸟的天堂。湿地属自然保护区，不应将候鸟的天堂改建为人的天堂。应引起广泛的讨论，按科学发展观办事。近年水灾低流量高水位的特点说明河床容积因自然或人为积滩而减少。
中国历来视治水为国家大事，因为古代国策就是“国必依山川”。我国版图有百分之六十以上是山，山间多是漫流的水，世界屋脊在中国，高山冰雪化为洪水而危害人的生命。夏禹以疏导法引江入海而奏效。以疏浚之土堆“九州山”，生民因山得救，生产斗争上升到哲学成为“仁者乐山，知者乐水。仁者静，知者动。知者乐，仁者寿”流传至今。
上海市政总院景观设计研究院有志于水，多年来通过对中国多条大江滨水空间/的考察技术实践和实地调查研究/树立了专项发展的系统思考。并一直寻觅跨学科整合的途径。从水生态、水环境、水城镇、水经济和水文化多方面进行全面、综合的设计和研究。在实践中注入人文和生态的理法，使城市服从河流、使河流肩负城市安全、公众游览休息和水空间设计得以融汇一体，成功地建成了国内多项高品质的城市滨水公共开放空间。屡获IFLA土地资源管理杰出奖、全国优秀勘察设计奖、上海优秀勘察设计奖，“天道酬勤”也。读者有幸可看到他们十年来实践代表作品二十项目。旨在向社会各界表达年轻的团队在多学科的支持下设计创新的思路，从而引发更广泛和深入的研讨，共觅当代中国风景园林设计之梦。
中国工程院院士
北京林业大学教授
孟兆祯
2014.12.15
Foreword
Follow the law of nature
and be in harmonious with nature
This is a famous saying by Guanzi，an ancient Chinese philosopher.The book for which I am going to write preface is The Return of Rivers.The name of this book impresses me because the concept of returning to nature，in fact，is the return to the cognition for nature.Why would us "make friends through literature，and learn from ancient times"？The reason is that human culture is an accumulation of generations，and past experience，if not forgotten，is a guide for the future.The cosmology of Chinese is "the nature and man unites as one"，“the harmony between the heaven and human”.People have a natural and social duality.If the universe is divided into two parts——nature and man，then human is the combination of heaven and man.Heaven is the monarch，and man is his subjects.Man's initiative performance is reflected by "the greatness of a man lends glory to a place"，and is manifested in the concept of "the scene looks more beautiful because of human design"on landscape.On the occasion of the 60th birthday of Shanghai Municipal Engineering Design Institute，it is very meaningful to celebrate this big occasion with ten year's work performance of the Landscape Design and Research Institute.It adds a material and spiritual treasure to the practice and theory of discipline in terms of society.For this reason we must first give our thanks to the hard work of this gardeners group.
Besides referral，appreciation，I would like to propose two questions to discuss together.We have ancient successful flood—controlling cases such as Dujiang Dam，and the method of which has only ten words，carved in a stone.The first four words are “appease water，provide tracks”，which means providing a stable water flow tracks，i.e.corresponding bed capacity.The other six words are "deep clean beaches and low weir".It means that if the river silts into beach，we need to dig deep in order to ensure adequate water run—off area，thus we can low the weir，so that the public can see the water.Shanghai is located in the Yangtze River estuary.It guides river into the sea.Therefore，the flowing of water is rather important.The Huangpu River filled rivers and lands with slag.Chongming Beach Land in Yangtze Delta has invested heavily on building a stone dam to stabilize the silted beaches，so as to reduce the volume of the riverbed.Statistics show that the value of the sea level rise of the Yangtze River is greater than that of the world average.The aggregations near Yangtze estuary are hard to disperse.After the completion of Chongming Wetland Park，the number of migratory birds and migratory species showed a continuous decreasing trend.Forests，oceans and wetlands are the world's three major natural resources，and are not man—made.Wetlands，being a part of the nature protection area，should not be transformed from a haven for migratory birds to a heaven for man.We should carry out wide discussions，and work according to the scientific concept of development work.In recent years，the characteristic of high—water flooding and low—flow explains that the volume of the riverbed decreased due to the siltation of sands because of natural or man—made reasons.
