Context The Sanjiangyuan region of the Qinghai-Tibetan Plateau—also known as the “Three Rivers’ Headwaters”—is the origin of the Yellow, Yangtze, and Mekong Rivers and therefore the key water source for hundreds of millions of downstream residents. Protecting this region’s ecosystems is a key priority for sustainable development in China and Asia. An important social dimension of Sanjiangyuan is the long-established and widespread presence of Tibetan Buddhism, particularly as manifested in the large number of monasteries throughout the region. However, the influence of cultural factors on environmental change remains largely understudied here. Objective We focus on two types of spatial associations—point-point and point-area features—to quantitatively investigate the effects of Buddhist monasteries on land use/cover change (LUCC) in surrounding landscapes. Methods We conduct a spatially-explicit analysis of Sanjiangyuan for two periods, 1990–2000 and 2010–2015, to identify and quantify the influence of the presence and spatial distributions of Buddhist monasteries on LUCC compared to village communities that lack monasteries. Results We found that the presence of monasteries is highly correlated with the preservation of natural ecosystems, specifically of grasslands and forests. Within monastery buffer zones with radii between 1 and 10 km, 7.13–9.30% more grassland area and 7.14–7.47% more forest area remained around monasteries compared to villages. This contrast decreased with increasing distance to the monastery/village. Overall, built-up areas were also much smaller around monasteries than around villages, while unused land was more commonly transformed to forests and grasslands around monasteries. Conclusions These findings strongly support the idea that Buddhist culture, as manifested through its physical institutions and communities, are instrumental in achieving desired landscape conservation outcomes.

The Yushu Tibetan Autonomous Prefecture is a typical Tibetan plateau area, and its ecological environment is very fragile. It is necessary to explore the terrain and cultural factors for the protection of the local ecological environment. We mainly investigated and quantified the effect of terrain factors and two typical plateau cultural landscapes (temples and villages) on the spatiotemporal variation characteristics of four types of forest landscape in the Yushu Tibetan Autonomous Prefecture from 1990 to 2015 using remote sensing (RS) and geographic information system (GIS) technology. The results showed that, under the influence of terrain factors, forest landscapes were only distributed in places with an altitude of 5055 meters above sea level (masl) to 6300 masl, with a slope of 0–27°, and the largest distribution area was shrubbery. The area of the forest decreased with the increase in altitude, and it first rose and then decreased with the increase in slope. Regression analysis results showed that the influence of altitude on closed forest land and open forest land followed a polynomial function, while that on shrubbery followed a logarithmic function, and the impact of slope on the three forest landscapes followed the amplitude version of a Gaussian peak function. Considering cultural factors, temples and villages did not determine the forest distribution in the same way as natural factors do, but they motivated the amount of forest over spatiotemporal scales. Temples had a greater influence on forest protection than villages, and this positive impact was stronger within 6 km. The area of forest distributed around the temple accounts for more than 45.67% of the total forest area, and this area has not changed significantly in 25 years. In summary, altitude and slope affect the natural distribution of the forest, and temples affect the scale of forest distribution. These results reveal the impact of terrain factors and cultural landscapes on forest distribution and could motivate an even more effective management for sustainable forest development.

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To ensure the safety of the water supply of the Panjiakou reservoir, in 2016, the Chinese central government comprehensively banned the fishing cage culture that had lasted for almost 30 years. However, the long-term effects and retention impacts of the government’s mandatory intervention on the reservoir water quality are unknown. To determine the reservoir water quality, we employed statistical methods along with the mathematical model to investigate the internal relationship since the construction of the reservoir. We applied seasonal trend decomposition using loess (STL) to explore the long-term and seasonality trend of monthly total nitrogen (TN) and total phosphorous (TP). To separate the impact of upstream water quality changes from cage culture on reservoir water quality, we employed generalized additive models (GAMs). We created a model, the LAKE2K model, to investigate the internal sources of the sediment that accumulated during the aquaculture period and its retardant effect. The results revealed that the concentration of upstream TN was more affected by non-point sources than by TP. The long-term policy of encouraging aquaculture has greatly contributed to the increase in the reservoir TP concentration rather than an increase in TN; the prohibition of cage aquaculture has resulted in a sharp drop in TP. After the ban, the sediment became the main source of TP. We suspect that the TP concentration of the reservoir and sediment will decrease gradually until a new equilibrium is reached within 10 years. This study offers lake managers an opportunity to increase their insight into the interaction of management measures with water quality and provides valuable information for the natural recovery of the eutrophic system.