位于青海杂多的吉富山是湄公河的上游澜沧江发源的地方，这里有着众多的源头，有科考的结果，也有人们心中的圣地。而对于我，在这片荒野上，豹子喝水的地方就是江的源头。枯草深处有一座绛红色的房子，那是这条河上最靠近源头的寺庙，自此而始，“众神”汩汩而出，直到三角洲，神的名目繁多，成了诸神的“容器”。在沿河流域苛刻的自然环境中没有“神”的陪伴，人们的祖先何以在此地敷衍生息？
河流穿过横断山脉，沿着澜沧江峡谷跃下高原，变得雄浑而喧嚣。人类的活动逐渐密集，消费时代的种种诉求也变得愈加直白与急迫。迅速提升的现代化的生活品质伴随着与传统生活方式和生活环境改变的冲突。祖辈的村庄湮没在拦河的水坝下，而另一些村庄则在二十一世纪用上了电灯。城市沿着河谷逶迤而建，新修的公路穿越了茶叶的产区，这条大河目睹了人们起高楼。
离开西双版纳，两岸的景色已经变成了热带雨林。澜沧江在这里离开中国，成了国际河流，被称为湄公河，历史上这一片广袤的山地因地形的阻隔与通讯的不便成了人们避难的处所，过去几百年里，周边国家不断的政权更迭、农民起义和经济危机将大量的人口从东向西从北向南推向这里，他们带来的鸦片的种植技术，使这里一度成为世界上最大的鸦片产地。几十年来，国际社会和当地政府的共同努力使得大规模的毒品交易已经遁形，而现代化的通讯技术和交通工具也迅速瓦解了这里的无政府社会。
热带的气候已经改变了人与河流的关系，早起做工的人们乘渡船离开家时，河边聚集起了洗漱的人群，一天的生活就这样开始。捕鱼的人们在河边用树干搭个架子铺上树枝便成了“家”，清晨划船出去捕鱼，完成交易后，便返回那个树枝搭成的“家”，他们与这条河相依为命。河水浇灌的三角洲，原本是人们的“米缸”。上游过量利用水资源，使得湄公河水量逐年减少，加之全球气候变暖导致海平面上升引发的海水倒灌，已经影响到了一千多万人的生存。
西贡，这座城市在1975年就改了名字，如今它叫“胡志明市”，历史上，这里是法属印度支那联邦实际上的经济中心，给这里留下了特殊的色彩和氛围。湄公河这时已分成了几条支流流向大海。那场渐渐被遗忘了的战争离结束并不久远，在博物馆里，我看到当年的美国士兵和从稻田、雨林里走出来的游击队员们站在一起，看着展墙上的照片，想起他们亲历了的战争流泪了。
黄昏降临，我回到河边，湄公河缓缓地流淌着，老迈而疲惫。湄公河，我们在青藏高原初次见面时就为你年轻而充满活力的美丽而感动，十年后的今天我们又在这里见面了，“与你那时的容貌相比，我更爱你现在备受摧残的面容。”
湄公河，我不知道是否会再见到你。
Jifu Mountain, located in Zaduo, Qinghai, is the birthplace of the Lancang River—the upper reaches of the Mekong. There are many recognized “sources” here: some identified by scientific expeditions, others held sacred in people’s beliefs.For me, on this stretch of wilderness, the place where a leopard drinks marks the river’s beginning. Amid the withered grass stands a crimson house—the monastery closest to the river’s source.
From that point onward, “the gods” begin to flow, murmuring all the way to the delta, where their countless names merge into one great vessel of divinity. In such a harsh environment along the river basin, without the companionship of gods, how could our ancestors have survived and endured here?
The river cuts through the Hengduan Mountains, plunges down the plateau along the Lancang Gorge, and grows mighty and restless. Human activity becomes denser; the desires of the consumer age more direct and urgent. Rapid modernization raises living standards while colliding with traditional ways of life and the natural environment. Ancestral villages are submerged beneath dammed waters, while others, in the twenty-first century, have only just received electric light. Cities stretch along the valleys; new highways carve through tea-growing regions. The great river bears witness as people build their towers high.
Leaving Xishuangbanna, the scenery on both banks turns to tropical rainforest. Here, the Lancang leaves China and becomes the international river known as the Mekong. Historically, this vast mountainous region, isolated by terrain and distance, became a place of refuge. Over centuries, waves of regime changes, peasant uprisings, and economic crises pushed populations east to west, north to south, into these lands.
With them came the cultivation of opium, once making this region the largest producer in the world. Decades of international cooperation and local governance have since diminished the large-scale drug trade, while modern communication and transportation have rapidly dismantled the once anarchic order.
The tropical climate has reshaped the relationship between people and the river.
At dawn, workers cross the river by ferry; along the banks, people gather to wash—the day begins this way. Fishermen build simple shelters of branches by the river, rowing out in the morning and returning after trading their catch. They live by and for the river. The delta irrigated by the Mekong was once the region’s “rice bowl.” But excessive water use upstream has reduced the river’s volume year by year, and global warming has caused seawater intrusion from rising tides— threatening the livelihoods of more than ten million people.
Saigon—a city renamed Ho Chi Minh City in 1975—was once the economic heart of French Indochina, still retaining a distinctive color and atmosphere from that past.
Here the Mekong divides into several tributaries before reaching the sea. The war that ended not so long ago is gradually fading from memory. In a museum, I saw American soldiers standing beside former guerrillas who had once emerged from rice fields and jungles. They looked at photographs on the wall and wept, remembering what they had lived through.
At dusk I returned to the riverbank. The Mekong flowed slowly—old and weary. When we first met on the Qinghai–Tibet Plateau, I was moved by your youthful strength and beauty.
Ten years later, meeting again here, I realize: “Compared to your youthful face, I now love even more your scarred and timeworn one.”
Mekong River— I do not know if we shall ever meet again.