According to GIAHS conservation requirements, IAHS must play an important role in maintaining the livelihood of indigenous households and protecting agricultural biodiversity and the biodiversity of related species, traditional knowledge and technologies about agriculture, traditional culture, values and organization, and traditional agricultural landscapes (FAO,2021). IAHSs as living, dynamic, compound agricultural production systems must be maintained through the production activities conducted by farmers according to indigenous traditional cultivation methods. Based on these conditions, IID in IAHS sites can be defined by five criteria. 1) IAHS conservation is the precondition of industrial development and the eventual goal; 2) Indigenous farmers are the main protectors participating in industrial development; 3) The target of industrial development is to improve the income of indigenous residents; 4) Local resources must be developed creatively based on analyses of temporal-spatial characteristics, quantity and quality, industrial bases, and agglomeration effects and industrial distributions; 5) Building an appropriate organization mode and the operation mechanism for the site to realize the organic integration of agriculture, secondary industry and tertiary industry. IID in IAHS sites aims to release the economic development potential and to improve the living standard of indigenous residents through a series of measures for industrial development, and then to promote effective IAHS conservation.

The IAHS is a complex system that consists of natural, economic, social, and cultural systems. The agricultural production system was created by local people based on the natural environment in the IAHS sites. The economic, social, and cultural systems are formed under the natural environment, thus they enjoy local features of the IAHS sites. These sub-systems of IAHSs must be protected according to their traditional features. As a result, IAHS conservation through IID must abide by certain principles, or else the IAHSs may be destroyed by development. Based on the requirements of IAHS conservation proposed by FAO, the IID in IAHS sites should include five principles.

(1) Conservation is the premise of IID. Industrial development aims to promote IAHS conservation. Any type of IID cannot be implemented at the cost of IAHS destruction.

(2) Agriculture is the base of any other industry. Any other industries are developed based on the agriculture. Those industries should be closely related to the agriculture, such as agricultural sightseeing, food processing, or the hospitality industry for agro-tourism. Those industries irrelevant to agriculture and destroying the local environment should be banned.

(3) Indigenous residents are the main part of the employment. Indigenous residents, as the persons growing up in the IAHS sites, better understand the connotations and characteristics of the IAHSs. They usually have a deep affection towards these IAHSs. They are the main protector and should be the beneficiary. In the IID, these indigenous residents should be considered first as employees.

(4) Industries should reflect local features. IAHSs are usually a class of traditional agricultural systems that reflects local cultures, agricultural production features, the geographical environment, and the natural resource characteristics. Therefore, IID should be based on the resources in the IAHS sites. The industries that may destroy IAHS or impact features of IAHSs should not be developed in IAHS sites.

(5) Industries should be sustainable in the economic, social, and environmental dimensions. In IAHS sites, IID are the drivers promoting IAHS conservation, rather than the eventual aim. These industries are developed on the condition of their sustainability in the economic, social, and environmental dimensions.

Longji Terraces are in Longji Town, Longsheng Various Nationalities Autonomous County, Guangxi Zhuang Autonomous Region, which is located in the southwest foothill of Yuechengling Mountain near the northern boundary of Guangxi. Longji Terraces are distributed in the hillside with elevations ranging from 300 to 1180 m. Forests are on the top of the mountains, which provide water for villagers’ living and farmland irrigation. Villages are seated in the terraces. Under the terraces are rivers. They typically constitute a magnificent and beautiful landscape and a sustainable human-nature compound system. In Longji Terraces, crop farming is characterized by red glutinous rice planted by human power. Feng Chicken, Cui Duck, and Longji Pepper are designated as National Products of Geographical Indication of China. Most people belong to Red Yao and Zhuang Nationality, with just a small proportion of them being Han, Dong, or Miao. Longji Terraces maintain the traditional farming culture and minor nationality culture to the present. In 2014, they were designated by the Ministry of Agriculture and Rural Affairs of China (MARA) as China-Nationally Important Agricultural Heritage Systems (China-NIAHS). In 2018, Longji Terraces and other three terraces in different provinces of China parceled as an integrated unit were designated by FAO as GIAHS (FAO,2021). Using the advantages of special resources, like the terraced landscape, featured agro-products, and minority cultures, the Longji people developed tertiary industries such as farming experience activities, terraced sightseeing, restaurants, hotels, and retail outlets of featured products, etc. These industries provided local villagers with employment opportunities and improved their income. The terraces received protection as well through the integrated development of agriculture and tourism.

Longji Terraces began to develop rural tourism in the 1990s. However, conflicts frequently arose in tourism development due to benefit imbalances among the different stakeholders. In 2004, when scientific benefit distribution schemes were designed between different stakeholders under local government participation and coordination, rural tourism evolved into a benign development status. For Longji Terraces tourism, the core attractions are the terraced landscape and the minority culture. In order to maintain sustainable development of Longji Terraces, the two classes of resources must be well maintained. However, these resources are living and must be protected by local farmers through their persistence in agricultural production and continuous participation in social communication activities. Therefore, the benefits for farmers must be safeguarded in tourism development.

In Longji Terraces, farmers’ incomes were from three sources (Fig. 3). The first source was agricultural production. Farmers planted red rice, sweet potatoes, and peppers, or they bred chickens and ducks, or cultivated fishes in the rice terraces. They were able to sell these products at a high price due to production using traditional methods. The second one was operating non-farm industries such as hotels, restaurants, retail operations, or logistics. According to our surveys, there were 187 hotels/restaurants in Dazhai Village, an administrative village in Longji Terraces, where there were 275 households in 2019. On average, each hotel/restaurant earned 100000 yuan. The third source was the dividends and compensation from tourism companies. According to the agreements signed by villages and Longji Tourism Companies and Longji Cableway Company, the villages in Longji terraced scenic region must plant rice for properly maintaining the terraced landscapes and the two companies pay a ratio of tickets as a dividend and compensation for planting to the villages. Taking Dazhai as an example, it received 7204000 yuan from the two companies in 2019, so the average household obtained 26000 yuan of dividends and compensation. The high income from tickets motivated farmers to try their best to plant rice. In conclusion, the integration of agriculture and rural tourism drove local people to actively protect Longji Terraces from destruction.

HHRTS is in Honghe Hani People Autonomous Prefecture of southwest China, which is located in the southern section of Ailao Mountain and distributed at an altitude of 1200-1900m, on the south bank of the upstream area of Red River. The rice terraces are distributed among four counties: Yuanyang County, Honghe County, Lvchun County, and Jinping County. HHRTS is a wonderful farming civilization mainly created by the Hani and Yi Nationalities in a special geographical environment. The traditional farming culture and minority culture are still well maintained in the Hani Terraces. With a long history of more than 1300 years, the terraces are still functioning today. Through long-term accumulation, Honghe Hani Terraces formed an agricultural culture that is characterized by planting red rice and Rice-Fish coculture. The landscape features are characterized by a whole ecosystem that consists of four elements of “forest-village-terraces-river systems”. Forests are situated on the top of mountains, which conserves water and provides water for villagers’ living and farmland irrigation. Villages are distributed in the terraces where farmers can easily access the fields. The rivers run from the mountains to the terraces. Honghe Hani Terraces are farmed by human power according to traditional farming methods. The red rice was designated as a National Product of Geographical Indication of China. The traditional coculture systems like Rice-Fish-Duck, Rice-Fish, and Rice-Loach, make full use of the light and heat resources. HHRTS are praised by anthropologists as a perfect example of the harmonious interaction between man and nature. In 2010, they were designated by FAO as GIAHS (FAO, 2021). In 2013, they were designated as a World Heritage Site by UNESCO. However, Hani Terraces have been confronting the threat of population outmigration due to the low economic benefit of small-scale activities without a famous product brand. For dealing with that problem, IID that is centered around red rice in Hani Terraces has played an obvious role in improving local farmers’ income to promote terrace conservation.

Like Longji Terraces, Hani Terraces also achieve the task of maintaining the terraced landscape through growing rice. Although they have landscape resources with a high value for tourism development, it is not feasible that developing the terraced tourism could motivate Hani farmers to persist in planting the Terraces. Due to the vast terraced area involving too many farmers and the differences of landscape quality among different villages, operating hotels and restaurants, as well as dividends and compensations from tourism companies, cannot benefit all the farmers in Hani Terraces. In addition, most peasant households had a low operation capacity and limited material and financial capital, which also hindered tourism development in Hani terraced region (Wang, 2020; Zhang et al., 2020). Therefore, the governments in Hani terraced areas had to lead the local farmers and enterprises in exploring a new effective pathway of IID to protect the terraces. For several years, they explored a new IID pathway suitable for Hani terrace conservation.

At first, the Hani people attempted to build an ecological agriculture brand depending on their clean farmland environment (Zhang et al.,2016), for example, developing specialized rice monoculture, a symbiotic system like Rice-Fish coculture, Rice-Fish-Duck coculture, rice-loach coculture, and traditional ecological animal husbandry and forestry (Fig. 4). In order to raise the additional value of agro-products, the governments encouraged enterprises and cooperatives to develop agro-product processing and manufacturing. Currently, the Hani terraced area produces a series of processed foods (red rice liquor, red rice noodles, red rice cookies, etc.) and daily-use chemical products (red rice shampoo, red rice shower foam, etc.). For obtaining more profits from the products, the governments also organized enterprises and farmers to build an integrated e-commerce system which includes building their own e-commerce platform, introducing agent shops, and using famous e-malls such as Tmall, Taobao, JD Mall and Alibaba. At the same time, they had also built an offline service network for farmers, cooperatives, and enterprises. Taking Yuanyang County as an example, there were 83 service points and 14 service stations to be built at the end of June 2018. The ecological agro-products and processed/made products could be sold through e-commerce. Red rice industries in Yuanyang County had created more than 200 million yuan of output value in 2017^①.(^① https://www.yndaily.com/html/2018/yuncaifu_0720/110811.html.)

As a result, the farmers in Hani Terraces obtained employment opportunities. Their incomes became diverse, for example, salary income from enterprises and non-farm income through operating e-shops or delivery industries other than agriculture. Farmers can generate more income through the operation of ecological agriculture in terraces and working non-farm jobs during a slack farming season in their own hometown. Therefore, the terraced landscape became an important resource and has been maintained well by the local farmers.

ADFS is in Aohan Banner of southeastern Chifeng City, Inner Mongolia Autonomous Region, China, located in the transitional zone between China’s farming culture and grassland culture. The Agricultural Heritage System is characterized by dryland farming combined with forestry and husbandry, a long foxtail millet and broomcorn millet farming history of 7700-8000 years, diverse grain varieties, traditional agricultural skills, and experience in use as well as the traditional dryland farming culture. Foxtail millet and broomcorn millet are the most important crops in ADFS, which play a core role in the economic development of the system as a whole.

As an agricultural system adapting to the local climate environment, ADFS contributes to local food security and disaster relief, such as for droughts. The diverse dry crops in the system provide various nutrients for people, which help the local people maintain the nutrient balance in their bodies. With chronic diseases increasing, these millets have been of interest to more and more people. Besides, these diverse traditional crops are also the genetic resources for cultivating new crop varieties. In ADFS, there are abundant indigenous farming skills and experiences with water-saving irrigation, comprehensive recycling of crops, and ecological disease and pest control. These traditional knowledge resources have important reference values for the sustainable evolution of modern development.

However, due to the impacts of modern farming methods and models with high efficiency, rural social structures and farmers’ core values have changed. This traditional agricultural system is facing threats and challenges, so it is urgent to explore an effective pathway for IAHS conservation based on developing the rural economy to improve farmers’ income in the ADFS site.

In recent years, to motivate farmers to grow dry crops according to traditional methods, the Aohan government had explored an IID road based on their agricultural features. The IID road is comprised of ecological agriculture, agro-product processing, and comprehensive marketing (Fig. 5). For ADFS, dryland farming is the core element in need of protection. It is also a precious resource due to its specificity. Around the farming system, ecological traditional grain growing practices were developed, for example, planting millet, bean, sorghum, and buckwheat. The grain products were bought by processing enterprises or cooperatives which processed them into manufactured products, for example, five colors millet, postpartum, and stone rolled millet. The straws from the crops were used to breed donkeys. The donkeys were also purchased by enterprises or cooperatives to produce commercial meat and milk. These processed products were sold by the enterprises, cooperatives, and individual businesses through various marketing channels including both online and offline sales. The online sales mainly depended on e-commerce marketing platforms, like Tmall, Pinduoduo, and Alibaba. The offline sales included supermarket sales and direct supply to the cafeterias of companies or governments. For example, Aohan millet had gone into 11 supermarket enterprises in Beijing, such as Wu Mart. In 2019, the gross sale of Aohan agro-products was up to 156 million yuan. One hundred and twenty-eight poverty-stricken households escaped from poverty.

With the industrial chain extending, income channels of farmers in the ADFS site have become increasingly diverse. They earned agricultural operation income through farming crops, breeding donkeys, and selling agro-products; they gained salary income from the processing enterprises or cooperatives by working in these business entities; they obtained non-farm operation income through cooperating with e-commercial enterprises, cooperatives, or operating their own individual business. Besides, the products continued to increase in price, and the production scale also grew due to the ascending popularity of the IAHS brand in recent years. For example, in Aohan, the price of foxtail millet rose to 8-15 yuan in 2019 from 4 yuan before 2014. The planting area of the millets increased to 9.2×10⁵ mu (about 61333.3 ha) in 2019 from 4×10⁵ mu (about 26666.7 ha) in 2012. With the increasing planting area of millet in Aohan, the number of donkeys being bred was also rising rapidly. According to the statistical data, the number of donkeys on-hand increased to 3.13×10⁵ in 2019 from 8.8×10⁴ in 2015. The people’s income was thus enhanced by 860 yuan in 2019.

Mulberry-dyke & Fish-pond System is a famous traditional circular agricultural system in southern China. The HMFS is seated in Zhejiang Province, and was created in the low-lying plain on the south of Taihu Lake. The agricultural system originated from the Spring and Autumn Periods (more than 2500 years ago). In the low plain, flood disasters frequently happen during the rainy season. In order to prevent flood disasters, the local people explored effective water conservancy works to store and drain excessive water through a network of “Zongpu” (narrow rivers in the north-south direction) and “Hengtang” (wide rivers in the east-west direction). They dug out low areas as fish ponds and piled the sludge around the ponds as dykes. The ponds are used to breed fishes. Mulberry trees are planted on the dykes. The mulberry leaves are harvested to feed silkworms; The silkworm excrement is used to feed fish; The fish excrement enriches the pond mud; The mud used as fertilizer is dug up for the mulberry trees. The landscape of HMFS consists of interconnected Mulberry-dykes and Fish-ponds, with the appearance of a chessboard. Based on the ancient ecological agricultural system, the IAHS site has formed a series of cultures, such as colorful traditional silk cultures and fish cultures, which are related to mulberry-planting, silkworm-rearing, and fish-raising.

In 2019, the system still had approximately 4000 ha of mulberry tree dykes and approximately 10000 ha of fish ponds. It was the largest, most concentrated, and well-conserved area of Mulberry-dyke & Fish-pond System in China. The circular system of agriculture takes full advantage of the water and soil resources based on the local natural environment, generating almost no pollution, promoting sustainable development of the local economy, and maintaining the livelihood of the local people. As an artificial wetland, the system enjoys rich biodiversity, including agricultural species like mulberry, silkworm, fish, and relevant biodiversity. It also has multiple ecosystem functions, such as water storage and flood regulation. The place which was not previously suitable for the survival of mankind was modified by the local people as a rich and world- renowned region. In 2018, it was designated by FAO as a GIAHS.

At present, the GIAHS conservation is confronted by many threats and challenges, for example, serious rural population aging, young labor outmigration due to outside work, and a lack of enthusiasm for aquaculture, as well as modern mechanized crafts replacing traditional handicrafts. This system needs an appropriate conservation pathway.

As a developed region in China, IAHS conservation in Huzhou Prefecture confronts many new problems in addition to some common problems. For example, planting mulberry trees for breeding silkworms has a high opportunity cost because they need lots of labor inputs due to the difficulty of industrialized and large-scale production. The lower benefit of planting mulberry for breeding silkworms relative to that of other models has become the main factor influencing the sustainability of HMFS (Liu et al., 2018b). Some Mulberry-dykes are broken due to lack of maintenance by the farmers. To address these problems, in recent years the local government, researchers, enterprises, and farmers commonly have explored an effective IID model to protect the GIAHS. At present, in Huzhou, an IID model of agriculture + tourism of studies and learning has been formed under the stakeholders’ participation (Fig. 6).

For HMFS, the Mulberry-dyke & Fish-pond landscape and the knowledge and culture regarding the planting of mulberry and breeding of silkworms and fishes are key elements. They are also the core resources for achieving IID. For effectively conserving HMFS, the local government invested 2.2 million yuan to establish a state-owned enterprise to manage the core conservation of HMFS. At the same time, it developed popular scientific education to improve the public’s perception of HMFS ^②(^② http://zj.chinadaily.com.cn/a/201901/17/WS5c3ff1dba31010568bdc43c5.html?from=groupmessage.). It encouraged enterprises and farmers to operate the circular ecological agriculture according to the traditional methods through authorizing the use rights of GIAHS LOGO. For example, Mrs. Qian, a farmer in Digang Village, contracted 2000 mu (about 133.3 ha) of ponds to operate the ecological agriculture. She earned a handsome income by breeding fishes and silkworm seeds. The fishes she bred were sold in large cities such as Shanghai and Hangzhou due to the GIAHS brand and the clean water environment in the ponds. She earned 5 million yuan in 2018 according to our survey.

Depending on the HMFS landscapes and traditional mulberry knowledge and culture, some enterprises developed tourism items on studies and learning for the public, for example, a museum for historical cultural displays, entertainment for experiencing the fish culture, or creative agricultural items based on HMFS. These tourism items on studies and learning attracted lots of tourists. Some local farmers and enterprises invested in operating services for tourists, for instance, hotels, restaurants, retail, and logistics. Diverse industries provided a great many employment positions for local farmers. Local farmers obtained earnings from multiple approaches including agricultural income by doing agriculture; salary income by doing non-farm jobs in tourism companies, service companies or agricultural companies; or non-farm income by operating hotels, restaurants, retail, and logistics. Overall, HMFS has formed an industrial chain on the landscape and traditional knowledge and culture, which is typical of the IID model comprised of primary industry and tertiary industry. This model brings considerable benefits to the stakeholders, and it has encouraged them to protect HMFS.