良渚古城从何而来？良渚古城外围水利系统因何而建、如何营建？良渚古城的保护和学术研究进行得怎么样了？2017年是良渚古城发现十周年，12月13日，良渚古城考古发现十周年新闻发布会举行，10年来良渚古城考古的研究和保护情况也得到梳理。
当天，第三届世界考古论坛在良渚召开，国内外著名高校和相关科研机构的近30位专家学者齐聚一堂，在激烈的观点碰撞和闪烁的思想火花中，良渚古城和外围水利系统的神秘面纱被一一揭开。
自1936年11月3日首次发掘以来，历经80多年风雨，良渚遗址考古研究取得了突破性的进展，随着良渚考古对外交流的发展，国际主流学术界逐步认识到良渚遗址在中华文明和世界文明研究中的重大价值。
堪称“中华第一城”
2007年，良渚古城发现和确认，标志着良渚遗址进入都邑考古新阶段，开启了通向良渚王国的大门。通过大规模勘探和地理信息系统分析，良渚古城包含内城3平方公里、外廓城8平方公里和外围水利系统100平方公里，在世界同类遗址中极为罕见，堪称“中华第一城”。
5300年前，良渚先民在中国长江下游的大地上建立了王国。在浙江省考古研究所的王宁远看来，良渚先民的人数在5000多年前剧增，似乎不是区域内部自然发展的结果，可能与西面太湖地区的人口迁移有关。
“气候事件导致先民由谷地向沼泽平原移动，稻作农业成为他们赖以生存和发展的新的物质基础。良渚文化正是建立在发达的稻作农业基础上。”王宁远解释说，在此过程中，专门用于稻作的农耕工具石犁等相继出现。
“古城选址三面环山，东边开放，既能保证安全，又有方便的交通，同时还包涵了一种‘居中’的概念。”在王宁远看来，良渚古城位于山间的沼泽湿地，有良渚港等河道贯穿其间。人们可以按照营建基层聚落的相同模式营建城市：采用堆墩的形式抬高居住面。堆墩也是良渚文化的显著特征之一。
选址于此也有一个最大的风险：古城西面的天目山系年降雨量达到1600至1800毫米，雨季经常暴发山洪。为了保护城邦，良渚古城外围水利系统便应运而生了。
水利工程世界领先
2015年良渚水利系统的确认，再次向世人证明了这座古城的辉煌。良渚古城外围水利系统由11条堤坝連接山体构成，是迄今已知中国最早、规模最大的水利系统，也是世界最早的拦洪水坝系统。良渚先民是怎样把水坝建起来的？除了抗洪，如此复杂庞大的水利系统还有什么功能？
据河海大学袁俊平副教授介绍，良渚先民发明了“草裹泥包”的方式堆垒加固坝体。即先用淤泥堆筑，外裹黄土，用芦荻、茅草把泥土裹成长圆形码成坝体。这种工艺类似现代人抗洪时用草包或编织袋装土筑坝，不仅增加了坝体抗拉强度，让水坝不易崩塌，也加快了堆筑速度。“草裹泥包”在良渚时期已成为临水建筑的常用工艺。
“良渚水利工程具有防洪、运输、灌溉等不同的功能。”浙江省文物考古研究所所长刘斌介绍，良渚水利工程通过高、低两级水坝，将水蓄留在山谷和低地内，解除了洪水威胁。遗址中的高坝大致可以阻挡短期内870毫米的连续降水，即可抵御本地区百年一遇的洪水。低坝内则是一个倒三角形的低洼地，根据现存的10米坝高推测，可形成面积达8.5平方公里的蓄水库区。
正是因为有了发达的水利系统，在进入稻作农业的同时，良渚文化在手工业等诸多领域也取得了进步，玉琮玉璧等开启了良渚文化玉器礼制的先河。
良渚古城与水利系统的关系如何呢？世界水利专家、来自美国辛辛那提大学的弗农·斯卡伯勒教授也分享了自己的观点。他说，过去一些经典的考古学研究显示，往往是先有城邦，再统一组织建设大型的基础设施，而良渚恰恰相反，是水利工程建设推进了都市化建设。
良渚古城水利系统的确认，也证实良渚古城由内而外具有宫城、内城、外廓的完整结构，是中国古代都城三重结构的滥觞。
遗址公园传承文脉
良渚古城遗址规模宏大，格局完整，10年来，良渚考古不断取得突破，良渚遗址已经成为中华5000多年文明史的重要物证。
在遗址保护上，我国将良渚遗址列入全国重点文物保护单位，划定了保护特区——良渚遗址保护区，设立了专门的保护机构——杭州良渚遗址管理委员会，编制了专门的保护法规——《杭州市良渚遗址保护管理条例》，使良渚古城遗址保护成为中国大遗址保护的典范。
在学术研究上，良渚古城的发现曾六次列入中国十大考古新发现，2013年被国际考古界选入“2011—2012世界10项考古新发现”，良渚古城的田野考古多次荣获中国田野考古的最高奖。浙江省考古界先后与英国伦敦大学学院、剑桥大学，日本奈良文化研究所、金泽大学，美国加州大学，中国社会科学院考古所、北京大学、河海大学、复旦大学、南京大学、浙江大学、山东大学等国内外学术机构合作，取得了许多研究成果。目前，良渚遗址国际考古研究中心正在筹建中，未来将进一步扩大国际学术交流与合作，推进跨国界、跨学科的研究。
良渚遗址的考古研究成果也为我们增强文化自信提供了强劲的考古学证据。全国统编中学《历史》教科书将良渚文化作为中国五千年文明的实证;《卞家山》《文家山》等考古报告和《权力与信仰》《良渚考古八十年》《良渚玉工》《良渚刻划符号》等图录相继整理出版;《良渚古城综合研究报告》《良渚古城垫石研究报告》即将出版。美国科学院院士、剑桥大学教授科林·伦福儒与刘斌合作的研究论文将在《古物》杂志上发表;英国伦敦大学学者庄奕杰和刘斌合作的研究文章将在美国科学院院刊上发表;良渚词条也将写入新修订的《大百科全书》。
保護良渚遗址，就是要弘扬中华文化，传承浙江文脉。“未来十年，我们将建设‘专家叫好、百姓叫座、国际领先、国内一流’的良渚文化国家公园，以还原5000年前良渚先民的生活生产情景。”杭州良渚遗址管理区党工委副书记、管委会副主任陈寿田说，目前，良渚遗址公园已列入首批（全国12家）国家考古遗址公园。
1936年的初冬，施昕更先生开启了这片土地上考古探索的先河;1959年良渚文化命名;1986年发现反山贵族墓地;1987年发现瑶山墓地和祭坛;2007年良渚古城发现;2015年良渚水利系统确认……尘封五千年的良渚文化正在逐渐揭开神秘面纱，成为中华文明新名片和世界文明史上璀璨的一笔。
On December 13， 2017， a press conference was held in Hangzhou to mark the 10th anniversary of the groundbreaking discovery of ancient Liangzhu City at Liangzhu Ruins in Yuhang District， Hangzhou. The press conference covered the latest development and informed the media of the now internationally recognized important role Liangzhu played in shaping the ancient Chinese civilization.
On the same day， an international symposium convened in Liangzhu. Over 20 top international archaeologists from renowned research institutes came all the way from Shanghai to take a closer look at Liangzhu Ruins after attending the Shanghai session of the conference in early November. The archaeologists visited Liangzhu sites on December 12.
The first archaeological dig around Liangzhu started on November 3， 1936. The study and excavation continued for decades. In 2007， the archaeological study of Liangzhu Ruins entered a brand new phase after the ruins of ancient Liangzhu City was discovered and confirmed. Data from large-scale explorations and geological studies indicate that the ancient Liangzhu City includes a three-square-kilometer inner city， an eight-square-kilometer outer city， and a 100-square-kilometer flood and irrigation system. It has been confirmed that the Liangzhu society is at least 5，000 years old.
Wang Yuanning， a researcher with Zhejiang Institute of Archaeology， pictured at the press conference what ancient Liangzhu City looked like and how it became what archaeologists see today.
A society flourished in Liangzhu about 5，300 years ago. The population grew fast possibly due to the migration of people from the west of Taihu Lake. Changes in weather enabled our ancestors living in valleys to move out to plains and marshes. Rice farming became the new material foundation for the survival and growth of the region. The Liangzhu Culture was firmly established on rice farming， as evidenced by unearthed stone ploughs and other farming tools.
The site of the city was in a place flanked by mountains on three sides， with the east opening to the outside world. Security and transport convenience must have been the two important factors for the choice of building a city there.
Floods from Tianmu Mountain to the west of Liangzhu were the biggest threat to the large-scale settlement as the annual rainfall averaged about 1，600 to 1，800 millimeters. The hydraulic system came into being to safeguard the city. Eleven dams have been discovered to have stood and connected with the adjacent hills to form a system. With the dams at different two levels， flood waters were contained in valleys and lowlands. Studies find that the high dams could have withstood the onslaught of a continuous 870-mm rainfall within a short period. In other words， the dams could have held out against once-in-a-century floods. The reservoir， encircled by low dams which now stand 10 meters tall， must have covered an area of 8.5 square kilometers. All the gates of the city allowed ships to enter and leave. The whole city was surrounded by a system of rivers， moats， and canals.
One archaeological discovery reveals how a technology now known as grass-wrapped mud made rapid dam building possible. Soil was the major building material for dams. Grass and reeds were used to wrap up soil cubes and wrapped mud cubes were heaped upon the slopes of dams. The mud cubes wrapped up in grass sacks gave strength to dams and made dam-building fast and efficient.
Unlike some ancient settlements in foreign countries where cities formed and then relevant infrastructures followed， the infrastructure in Liangzhu came first before the whole city was constructed.
The hydraulic system of Liangzhu culture is the earliest large-scale hydraulic system found in China. The recovery of the 5000-years-old hydraulic system is very important to the investigation of ancient Chinese hydraulic history. It is also the earliest flood control system in the world.
The hydraulic system has also proved that the ancient walled settlement of Liangzhu culture had a complete capital city structure with palace wall， inner city wall， outer city wall， and with the hydraulic system surrounded outside the city. This structure has strongly influenced the constructions of capital cities in later periods， which provides significant research information for the investigation of the Chinese city history.
The ancient settlement of Liangzhu culture signifies one of the earliest state patterns in China. This is a solid and convincing piece of evidence for 5，000 years of Chinese civilization. The recovery of the hydraulic system outside the walled enclosure has significantly contributed to the investigation of the appearance and development of the early state of Liangzhu and the origin of Chinese civilization. Moreover， it is also important to the research of the history of world civilizations.
