The 800-mile Dongting has always been talked about by scholars. There are reeds and boats by the lake, and there are beautiful rice fields by the lake. From a scientific point of view, Dongting Lake, located in the middle reaches of the Yangtze River, is a natural storage lake of the Yangtze River and one of the important wetlands in the world. For thousands of years, it has been called the land of fish and rice. However, the separation between paddy field and wetland has never stopped here, because Dongting Lake has been surrounded by large-scale farmland several times in history, and the wetland ecosystem has been destroyed to some extent. Therefore, the next thing is to return the fields to the lakes. Nowadays, in Zeguo, Shui Bo, most of the cotton fields in rice fields have turned into depressions, where local people still raise fish, ducks and cages.

Xinjiang Karez was blocked by rivers to build Jiangnan.

Speaking of karez in Xinjiang, some people may ask what it has to do with rice fields. Turpan, the representative place of Karez, is rich in cash crops such as grapes, and there is basically no shadow of rice fields. However, on the edge of the desert in Shanshan, Xinjiang, due to the magic of Karez, a fertile land was created under the sand mountain. At the same time, we can see the desolation in the desert in the north of Saibei and the misty rain in the rice fields in the south of the Yangtze River, which is the charm of the agricultural engineering heritage of Karejing.

Karez was recorded as early as the year of Historical Records, and it was called well canal at that time. Most of the existing Karez wells in Xinjiang were built after the Qing Dynasty. Today, it still irrigates vast oases and fertile fields. Karez, Wan Li Great Wall and Beijing-Hangzhou Grand Canal are also called the three ancient projects in China.

The structure of Karez is generally composed of four parts: shaft, underground passage, ground passage and waterlogging dam (small reservoir). In spring and summer, a lot of rain and snow flow down the valley and sneak into the Gobi Desert. People skillfully use the slope of the mountain to irrigate farmland with underground undercurrent, creating karez. The dam will not evaporate a lot of water due to high temperature and strong wind, so the flow rate is stable and the self-flow irrigation is guaranteed.

Now, although many places in Xinjiang have built large-scale canals and reservoirs, Karez still plays a special role in modernization.

China rice culture originated in Jiangxi for ten thousand years.

After talking with Min Qingwen, a researcher at the Heritage Research Center of Institute of Geography, Chinese Academy of Sciences, I learned that in addition to the familiar terraces, there are many living agricultural heritages in China, such as the Gong Mi culture in Jiangxi. He was very excited when he mentioned the once-in-a-million-year China Rice Festival, saying that even people who often study rice can't help but admire the once-in-a-million-year Gong Mi, which is as white as jade and smells like rice flowers.

Wannian County is located in the northeast of Jiangxi Province, downstream of Le 'an River and southeast bank of Poyang Lake. With mild climate, abundant rainfall and scattered streams, it is known as the birthplace of rice culture in China. In the 1990s, Chinese and foreign archaeologists jointly excavated the Wannian Fairy Cave and the bronze ring carving site. In the early Neolithic age (about 12000 years ago) of the site, there were cultivated rice planted with silica, which suddenly advanced the rice planting history of China discovered at Hemudu site in Zhejiang by 5000 years.

Yunnan Yuanyang Terrace is a classic wonder in the history of human rice cultivation.

Paddy fields that have existed for tens of thousands of years have been given a scientific name, agricultural landscape heritage. China's agricultural cultural heritage is all-encompassing, including the Neolithic agricultural heritage; Dujiangyan, Lingqu, Karejing and other agricultural engineering heritages; Agricultural literature heritages such as Qi Yaomin's Book, Nong Sang Yao Ji and Nong Zheng Quan Shu; There are countless agricultural scientific and technological heritages such as mulberry pond, intensive cultivation and ecological textile. Among them, the most ornamental and tourist value is the agricultural landscape heritage, which mainly refers to some small agricultural facilities or agricultural elements with ornamental value. The most representative are terraced fields and villages with cultural characteristics. The most classic terrace wonder in China is Yuanyang Terrace in Honghe Hani and Yi Autonomous Prefecture.

Yunnan Yuanyang terraces are mainly distributed in the vast mountainous areas between Ailao Mountain and the lower reaches of Yunnan Red River and Lancang River. They are masterpieces handed down from generation to generation by the Hani people. The terraced fields cultivated by the Yanghani people change with the mountainous terrain and adapt to local conditions. Plow when the slope is gentle, plow when the slope is steep, and plow even the gap under the ditch. Therefore, terraces are a few acres in size, and dustpans are just the size, often thousands of acres on a slope. Yuanyang terraced fields are large-scale and magnificent, covering the four counties of Honghe, Yuanyang, Lvchun and Jinping on the south bank of Honghe. Yuanyang County alone has 6.5438+0.7 million mu of terraced fields, which is the core area of Hani terraced fields in Honghe. Yuanyang county is almost all mountains, and terraces are built around the mountains, and the slope of terraces ranges from 15 degrees to 75 degrees. As far as a hillside is concerned, the highest terrace reaches 3000, which is rare in terraced landscape at home and abroad. There are three scenic spots in Yuanhani Terrace: Bada Scenic Area includes Qingkou, Quanfuzhuang, Malicun, Zhulu, etc. 14000 mu of terraced fields; Hukou Scenic Area includes nearly 6,000 acres of terraced fields in Meng Ping, Dongpu, Amungkong and Baoshan Village. Duoyishu Scenic Area includes tens of thousands of acres of terraced fields in Duoyishu, Ai Chun and Dawazhe. So many terraces are covered by vast forests and clouds, forming a magical and magnificent landscape. These scenic spots are the core protected areas to be declared as World Heritage at present.

Tian Shan, like a giant non-written history book, intuitively shows the long history of Hani ancestors' tenacious struggle and prosperity under the dual pressure of nature and society. Many Hani legends show that Hani people believe that rice has existed since the beginning of the world. This shows that Hani nationality is one of the earliest nations to domesticate wild rice. For thousands of years, the Hani people domesticated the wild rice in the Sanjiang Gorge of Ailao Mountain into upland rice, and improved the upland rice into rice. Under the unique ecological environment, the Sanjiang Basin has become one of the areas where rice was domesticated and cultivated in the early stage.