The response of key ecosystem services to land use and climate change in Chongqing: Time, space, and altitude

Abstract

Mountainous landscapes are particularly vulnerable and sensitive to climate change and human activities, and a clear understanding of how ecosystem services (ES) and their relationships continuously change over time, across space, and along altitude is therefore essential for ecosystem management. Chongqing, a typical mountainous region, was selected to assess the long-term changes in its key ES and their relationships. From 1992 to 2018, the temporal variation in water yield (WY) revealed that the maximum and minimum WYs occurred in 1998 and 2006, which coincided with El Niño-Southern Oscillation and severe drought events, respectively. Soil export (SE) and WY were consistent with precipitation, which reached their highest values in 1998. During this period, carbon storage (CS) and habitat quality (HQ) both decreased significantly. ES in Chongqing showed large variations in altitude. Generally, WY and SE decreased with increasing altitude, while CS and HQ increased. For spatial distribution, WY and SE showed positive trends in the west and negative trends in the east. In regard to CS and HQ, negative trends dominated the area. Persistent tradeoffs between WY and soil conservation (SC) were found at all altitude gradients. The strong synergies between CS and HQ were maintained over time.

Fusing Satellite Precipitation Products Based on Top–Down and Bottom–Up Approaches and an Improved Double Instrumental Variable Method for the Chuanyu Region, China, from 2007 to 2019

“…Moreover, it can be seen that the increasing trend locations are gathering at the central part of the Chuanyu region, where the altitude has a significant difference. This result is consistent with the pattern of precipitation in the Chuanyu region, which has been reported by related climate studies [77,78]. Furthermore, this proves the value of the proposed method as well as that of the fused products for providing accurate precipitation information, and they could be useful for other related climatology studies.…”

Spatiotemporal Analysis and Multi-Scenario Prediction of Ecosystem Services Based on Land Use/Cover Change in a Mountain-Watershed Region, China

“…As the primary land use type supporting CS and HQ in the QJW, the forest land decreased by 1.03%. Land use type was the main factor influencing the spatial heterogeneity of CS and HQ, with q values of 0.4 and 0.5, respectively, which were similar to previous studies [64], as woodland has the highest carbon intensity level in the QJW and is less affected by human activities than other land use types, leading to higher values of CS and HQ. Meanwhile, the built-up land increased by 269.90% in the past 30 years, with enhanced disturbances of the QJW by frequent human activities.…”

Effects of maturity of citrus fruits on their stalks cutting force

“…When the solid solution content was less than 7.7%, the actual value of the solid solution content obtained in the experiment in 2020 was larger than the predicted value of the model; When the content was greater than 7.7%, the actual value was smaller than the predicted value of the model. According to the analysis of the reasons, the average temperature in Chongqing, China in October 2020 was 16.3°C, which was significantly lower than 18.1°C in the same period in 2019, and the sunshine duration was also less than that in October 2019 [37] , resulting in the solid solution content of citrus fruits during maturity in 2020 was lower than that of the same period in 2019. At the same time, since the temperature decreased earlier in 2020 than it did in 2019, the change in solid solution content of citrus fruits in 2020 was earlier than that of 2019, but the trend was still basically the same.…”