Success Factors of Irrigation Projects Based on A "Public–Private Partnership" Model in A Mountainous Area: A Case Study in the Nujiang River Valley, China

Irrigation systems are critical for food security and drought adaptation in mountainous areas. However, lack of funding and low efficacy of government-funded irrigation projects hinders irrigation infrastructure development. A public–private partnership (PPP) model is recommended for irrigation development, but its application in mountainous areas has not been well-documented and analyzed. Based on a case study of pumping station projects in the Lujiang Flatland in the Nujiang River Valley of Southwestern China, this paper aims to reveal the critical success factors of the PPP model in the development of agricultural irrigation infrastructure in mountainous areas. Results showed that the basic models of PPP projects in the study area can be described as follows: (1) private companies invested in and constructed pumping stations; (2) communities operated the stations; (3) farmers paid for the services; and (4) private companies profited from charging water fees, obtaining policy supports, or utilizing farmlands. The main success factors include: (1) rational project design according to local conditions; (2) multi-centered management mechanisms; (3) balanced cost- and risk-sharing mechanisms; and (4) building mutual trusts among stakeholders. This study offers applicable lessons and useful insights for irrigation water development projects and adaptation to drought in mountainous rural communities.

Evaluation of Various Precipitation Products Using Ground-Based Discharge Observation at the Nujiang River Basin, China

Precipitation observation and prediction is difficult in many high elevation regions due to the complex terrain and the lack of in situ observations for comparison. The Nujiang River (upper and middle Salween River) basin in the Tibetan Plateau is no exception. Because of this shortcoming, we propose the use of gauge-observed discharge time series at the basin outlet (e.g., Jiayuqiao hydrological station) to evaluate the performance of four different precipitation products (e.g., satellite-based products and reanalysis datasets). A physically-based distributed cryosphere hydrological model with coupled snow and frozen soil physics was adopted to transfer the basin-wide gridded precipitation into the basin-outlet discharges. First, we corrected and evaluated the four precipitation products. A correlation relationship was established between each precipitation product and the available (limited) gauge rainfall within different elevation zones, and then used to correct the four precipitation products in the study basin. Secondly, a distributed cryosphere hydrological model was used to simulate the basin-outlet runoff driven by each corrected precipitation product. The results indicated that modern-era retrospective analysis for Research and Applications, version 2 (MERRA2) precipitation has better performance in the upper Nujiang River basin relative to the other precipitation products based on comparisons of observed and simulated runoff.

A new species of Behningia Lestage, 1929 (Ephemerotera: Behningiidae) from China

A new species of sand-burrowing mayfly (Ephemeroptera: Behningiidae), Behningia nujiangensis Zhou & Bisset, is described based on more than 50 nymphs collected from the Nujiang River in Yunnan Province, P.R. China. This is the first species of the family Behningiidae discovered in China. It is also the second species of genus Behningia, and the third species of the family Behningiidae collected from the Oriental biogeographic region. The shapes of the labrum and the labium in B. nujiangensis are markedly different from those found in other species of Behningia. Differences in the mandibles, the galea-lacina of maxillae, and both the prothoracic and metathoracic legs differentiate B. nujiangensis from both B. baei and B. ulmeri. The biology of and conservation challenges for B. nujiangensis are also briefly discussed.