Integrating revised DPSIR and ecological security patterns to assess the health of alpine grassland ecosystems on the Qinghai-Tibet Plateau.

Alpine grassland ecosystems on the Qinghai-Tibet Plateau (QTP) provide critical services but face threats from human activity and climate change. Ensuring ecosystem health is vital for sustainability and preserving ecosystem services and processes, especially in delicate ecosystems such as the Gannan alpine grasslands. However, there is currently a lack of a comprehensive model that integrates ecosystem structure, function, processes, and socioeconomic factors.

Estimating rainfall interception loss of three dominant shrub species in an oasis-desert ecotone using in situ measurements and the revised Gash analytical model.

Canopy interception loss affects the local water budget by removing a non-negligible proportion of rainfall from the terrestrial surface. Thus, quantifying interception loss is essential for thoroughly understanding the role of vegetation in the local hydrological cycle, especially in dryland ecosystems. However, sparse shrubs in dryland ecosystems have not been sufficiently studied, owing to time- and labor-intensive field experiments and challenging model parameterization.

Experimental partitioning of rainfall into throughfall, stemflow and interception loss by Haloxylon ammodendron, a dominant sand-stabilizing shrub in northwestern China.

Rainfall partitioning by the vegetation canopy represents a significant component of the local hydrological cycle by reshaping the amount and spatial distribution of rainfall. Measuring the components of rainfall partitioning, however, has been a challenging task due to laborious- and time-consuming field experiments. In this study, to probe the influences of long-term afforestation on dynamic patterns of rainfall partitioning, the dominant sand-stabilizing shrub Haloxylon ammodendron at three different ages was selected for field measurements during the 2020-2021 growing season.

[Dynamics of sap flow density in stems of typical desert shrub Calligonum mongolicum and its responses to environmental variables].

Independent measurements of stem sap flow in stems of Calligonum mongolicum and environmental variables using commercial sap flow gauges and a micrometeorological monitoring system, respectively, were made to simulate the variation of sap flow density in the middle range of Hexi Corridor, Northwest China during June to September, 2014. The results showed that the diurnal process of sap flow density in C. mongolicum showed a broad unimodal change, and the maximum sap flow density reached about 30 minutes after the maximum of photosynthetically active radiation (PAR) , while about 120 minutes before the maximum of temperature and vapor pressure deficit (VPD).

Temporal variations of CO2 concentration near land surface and its response to meteorological variables in Heihe River Basin, northwest China.

Atmospheric CO2 concentration (CC) near land surface and meteorological variables have been measured at four sites, named Yeniugou (alpine meadow and permafrost), Xishui (mountainous forest), Linze (oasis edge) and Ejina (lower desert), respectively, in Heihe River Basin, northwest China. The results showed that, the half hourly CC at night was larger than in daytime, and the daily averaged CC was the largest in winter. The averaged CC of 932 d at the Linze was about 418 ppm, was about 366 ppm in the 762 d at the Ejina.