About 10% of the Earth’s butterfly species inhabit the highly diverse ecosystems of China. Important for the ecological, economic, and cultural services they provide, many butterfly species experience threats from land use shifts and climate change. China has recently adopted policies to protect the nation’s biodiversity resources. This essay examines the current management of butterflies in China and suggests various easily implementable actions that could improve these conservation efforts. Our recommendations are based on the observations of a transdisciplinary group of entomologists and environmental policy specialists. Our analysis draws on other successful examples around the world that China may wish to consider. China needs to modify its scientific methodologies behind butterfly conservation management: revising the criteria for listing protected species, focusing on umbrella species for broader protection, identifying high priority areas and refugia for conservation, among others. Rural and urban land uses that provide heterogeneous habitats, as well as butterfly host and nectar plants, must be promoted. Butterfly ranching and farming may also provide opportunities for sustainable community development. Many possibilities exist for incorporating observations of citizen scientists into butterfly data collection at broad spatial and temporal scales. Our recommendations further the ten Priority Areas of China’s National Biodiversity Conservation Strategy and Action Plan (2011–2030).

Southwest China’s Yunnan province is evolving into one of the world’s largest hydro-power-producing regions. It already rivals the world’s largest hydro-producing nations. However, five of Yunnan’s six basins are international and therefore its hydropower development is of great academic and geopolitical interest. While the implementation of large projects on Yunnan’s three large rivers (Jinsha, Mekong and Nu) is relatively well studied, hydropower development outside these three main streams is hardly known. Here, we identified 128 large hydropower projects (≥50 MW) having a capacity of 16.5 GW, along with another 16.4 GW of other types of power generation, neither of which has been discussed in the academic literature yet. The paper utilizes a powershed approach to study the rapid hydropower development underway in Yunnan, both in its implication and challenges (at basin and administrative level) as well as in its trade-offs within the broader electricity context. Yunnan’s power generation and consumption patterns are characterized by diverging interests of local/provincial usage and export utilization. Within the province, the largest (hydro-) power users are energy/electricity intensive industries, which themselves have strong impacts on land use changes. Yunnan is also evolving as a major power exporter, already in 2013 exporting about one-third of its generated electricity mainly to Guangdong’s Pearl River Delta. We see a need for a critical revision of those existing generation and consumption paradigms, which includes a rethinking of major development modes, both in terms of future hydropower generation and utilization projects as well as export obligations.

The Yaluzangbu-Brahmaputra River is a hotspot for the discussions on regional security. The interactions on water between China and India are key to realizing water-related 2015 Sustainable Development Goals (SDG) targets in the basin. Using a series of secondary literature information, and the method of event studies, we created a timeline of the Sino-Indian relation events since the 1950s, analyzed the correlations among the contents, the duties by each side, the events of water cooperation, and the diplomatic events between them. We found the following dilemmas hamper water cooperation: (1) The scopes of, and steps towards, transboundary water cooperation are hampered by patchy Sino-Indian diplomatic relations; and (2) there is a lack of motivation for China to cooperate with India without benefits sharing, given that China has undertaken more duties and has often received negative feedback. However, we also found the following pathways toward improving water cooperation: (1) A national cooperation mechanism on transboundary rivers has been established, which may be beneficial for further water cooperation; and (2) a channel for interdisciplinary dialogue should be encouraged to bridge the disparate outlooks and improve interactions between policymakers and scientific experts.

To date, hydropower dams raise numerous interpretations about their impact on the Lancang-Mekong River. While most research studies analyze the negative aspects of hydropower development on people’s livelihoods and local environments, the hydropower sector was historically one of the most iconic economic segments facilitating transboundary water cooperation for decades. By using the constructive discourse analysis and critical political ecology approach, the presented text (1) outlines the current environmental narratives over the Lancang-Mekong hydropower development and (2) explores the politicization of the Chinese mainstream dams. The data were collected upon the multi-level content analysis of relevant sources and double-checked with the Lancang-Mekong Cooperation and Conflict Database (LMCCD) monitoring over 4000 water-related events among six riparian countries between 1990 and 2021. Our data show that (i) there is a stark contrast in positive and negative narratives over the rapid hydropower development, (ii) the impact of mainstream dams on the river is more often discussed than that of tributary dams, (iii) implications of the hydropower dams are often interpreted upon the non-traditional research inputs rather than widely accepted studies, and (iv) developing the contradictory arguments through social and public media contributes to greater polarization of the multi-stakeholders’ viewpoints in the accountable research dialogue.

The family of Papilionidae (Lepidoptera: Papilionoidea) is a group of butterflies with high ecological and conservation value. The Hengduan Mountains (HMDs) in Southwest China is an important diversity centre for these butterflies. However, the spatial distribution pattern and the climate vulnerability of Papilionidae butterflies in the HDMs remain unknown to date. The lack of such knowledge has already become an obstacle in formulating effective butterfly conservation strategies. The present research compiled a 59-species dataset with 1938 occurrence points. The Maxent model was applied to analyse the spatial pattern of species richness in subfamilies Parnassiinae and Papilioninae, as well as to predict the response under the influence of climate change. The spatial pattern of both subfamilies in the HDMs has obvious elevation prevalence, with Parnassiinae concentrated in the subalpine to alpine areas (2500–5500 m) in western Sichuan, northwestern Yunnan and eastern Tibet, while Papilioninae is concentrated in the low- to medium-elevation areas (1500–3500 m) in the river valleys of western Yunnan and western Sichuan. Under the influence of climate change, both subfamilies would exhibit northward and upward range shifts. The majority of Parnassiinae species would experience drastic habitat contraction, resulting in lower species richness across the HDMs. In contrast, most Papilioninae species would experience habitat expansion, and the species richness would also increase significantly. The findings of this research should provide new insights and a clue for butterfly diversity and climatic vulnerability in southwestern China. Future conservation efforts should be focused on species with habitat contraction, narrow-ranged distribution and endemicity with both in situ and ex situ measures, especially in protected areas. Commercialised collecting targeting these species must also be regulated by future legislation.

The Tijuana River Estuary (TRE) has been a public health hazard and point of contention between the United States and Mexico for decades, with sources of pollution on both sides of the border. The goal of our study is to determine the presence and dynamics of chemical contamination in the TRE. We sampled sediment from four TRE locations in the U.S. during stable dry conditions and immediately after a wet weather period. Organic chemicals were initially screened with non-targeted analysis using gas chromatography high-resolution mass spectrometry (GC/HRMS) that tentatively identified 6978 chemicals in the NIST 20 database. These tentative identifications were filtered using the USEPA CompTox database to guide quantitative targeted analysis at detection limits below 1 ng/g dry weight sediment. Quantitative targeted analysis of 152 organic pollutants and 18 inorganic elements via GC/HRMS revealed generally higher concentrations of contaminants in dry weather sediments compared to wet weather sediments. The highest concentrations of all chemical classes were detected at the site closest to the U.S.-Mexico border, followed by an urban area near Imperial Beach, California, U.S. All sites exhibited a mixture of petrogenic and pyrogenic polycyclic aromatic hydrocarbons (PAHs). Current-use pesticides were dominated by pyrethroid insecticides and the thiocarbamate herbicide s-Ethyl dipropylthiocarbamate (EPTC), while the U.S.-banned organochlorine pesticides were dominated by chlordanes, dieldrin, and dichlorodiphenyltrichloroethane (DDT) and its degradation byproducts. Polychlorinated biphenyl (PCB) concentrations were greatest at the site closest to the U.S.-Mexico border but in the low nanogram-per-gram range. Phthalates were only found at the same site, with relatively high concentrations of bis(2-ethylhexyl) phthalate. This study provides positive identification and quantitative concentrations for organic pollutants in TRE sediments. Our data suggest that there are multiple sources of chemical contamination in the estuary, including possible transboundary movement of pollutants from Mexico.