Transplanted Ginkgo growth rates indicate common Chinese nursery techniques may severely limit urban ecosystem services.

China has experienced history's largest rural-to-urban migration. The social, economic, and environmental challenges brought about by urbanization are diverse and complex. Given China's national goal to achieve carbon neutrality by 2060 and commitment to urban sustainability, large cities have focused on urban greening initiatives. Yet, studies seeking to quantify ecosystem services and disservices only assess healthy, mature trees, rather than those with severe damage, declining health, or lack of vitality due to poor management. In this short communication, we conducted a case-study in one of China's major nursery stock-producing cities, Chengdu, on a common street tree, Ginkgo biloba, to assess the long-term impact of one of the most common yet extreme nursery transplant practices on tree growth (traumatic root-cutting of 'super-large' nursery stock). We used tree-ring data collected in a typical urban greenspace from 23 Ginkgo trees, including 18 trees transplanted as 'super-large' nursery stock and a control group (5 trees) transplanted as small-caliper trees. We found the trees transplanted as 'super-large' nursery stock experienced declining tree growth with decades of lost landscape potential likely due to traumatic root-cutting at the time of transplant from nursery to landscape. The control group allowed contrast between the growth patterns of 'super-large' transplanted trees with those that remained healthy, being transplanted as smaller-caliper trees. For the 'super-large' trees, we found a decrease in carbon sequestration from 7.6 kg C yr-1 on average per tree in 2001 to about 1.5 kg C yr-1 on average per tree in 2021, while no decreasing trends were observed among the control trees. This implies a negative impact on multiple expected ecosystem services including carbon sequestration, shade, canopy coverage, and pollutant mitigation. These results highlight the unrecognized costs of common Chinese nursery and transplant techniques on urban landscape trees, necessitating more research, science-based policies, and better management techniques.

An ethnobotanical survey of wild edible plants used by the Yi people of Liangshan Prefecture, Sichuan Province, China.

BACKGROUND: Due to historical perceptions of Liangshan Yi Autonomous Prefecture (Sichuan Province, China) as being a violent place, and due to its rugged terrain, cultural differences, and relative inaccessibility, few researchers have conducted in-depth ethnobotanical investigations in Liangshan. But wild edible plants (WEPs) are widely consumed by the Yi people of Liangshan, and their associated ethnobotanical knowledge remains relatively unknown, especially outside of China. This study aimed to (1) investigate the WEPs used by the Liangshan Yi, (2) document the traditional knowledge held about these plants, (3) analyze their special preparation methods and consumption habits, and (4) identify species with important cultural significance to the Liangshan Yi. METHODS: During 2016-2017, 396 Yi individuals were interviewed in 1 county-level city and 6 counties across Liangshan. Prior informed consent was obtained, and multiple ethnographic methods were utilized, including direct observation, semi-structured interviews, key informant interviews, informal discussions, and field visits. Market surveys were conducted in April, July, and August 2017 by interviewing 38 Yi merchants selling WEPs in 6 Liangshan traditional markets. We collected information about the parts consumed, preparation methods, consumption habits, growth pattern of species, collection months, market prices, and other uses of WEPs. Use values (UVs) were calculated to analyze the relative cultural importance of each WEP. RESULTS: In total, 105 plant species belonging to 97 genera and 62 families were recorded. Rosaceae was the family with the largest number of species (14), and herbs (58 species) were the dominant growth form reported. Fruits (34 species), roots (21 species), and tender shoots (20 species) were the primary plant parts used for snacking and cooking. There were 6 main preparation and consumption methods of WEPs reported, ranging from primary food, famine food, snack, spice, culinary coagulant, and medicine, among a few other uses. The Liangshan Yi mainly collect WEPs from March to October, seldom collecting from November to February. There were 35 species of WEPs sold in the markets we visited in Liangshan. The price of medicinal plants was much higher than the price of food and fruits. In total, we documented 49 species of edible medicinal plants in Liangshan, accounting for 44.7% of all WEPs. They can be used for treating 27 medical conditions, including cough, diarrhea, injury, and headaches. The plants with the highest UVs were Berberis jamesiana (1.92), Pyracantha fortuneana (1.87), and Artemisia capillaris (1.44) indicating that these species are the most commonly used and important to the Liangshan Yi's traditional life and culture. CONCLUSIONS: The traditional knowledge of WEPs from the accumulated experience of the Yi people's long period residing in Liangshan reflects the cultural richness of the Yi and the plant diversity of the region. Future research on the nutrition, chemical composition, and bioactivity of the WEPs are needed. Some species with high medicinal value but with sharp wild population decline should be surveyed for resource assessment, conservation, and domestication potential.