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Understanding the variability in soil hydraulic conductivity in the mountainous headwaters is critical to the modeling of mountainous runoff and the water resources management of river basins, especially in the arid and semiarid areas. In this study, a total of 32 soil profiles with five layers within 0–70 cm were sampled under different land cover types: forest, meadow, high coverage grassland (HCG), medium coverage grassland (MCG), and barren land in the upper stream of the Heihe river watershed, Northwest China. Saturated hydraulic conductivity (KS) was measured for each sample. The vertical variation of KS and soil hydrological response under different land covers were analyzed. Results show that KS value in layer 5 was significantly lower than the values of above four layers. KS decreased in the order of forest, meadow, HCG, MCG, and barren land, corresponding to the degree of vegetation degradation. The KS decreased with depth under forest, HCG, and barren land, but increased first and then decreased under meadow and MCG. The dominant stormflow paths for different land covers were different: forest was dominated by deep percolation, HCG was dominated by subsurface flow (SSF), meadow was prevailed by Hortonian overland flow and had no SSF, while MCG and barren land were also dominated by Hortonian overland flow, but still formed SSF. This result provides important information for improving the accuracy of mountainous hydrological modeling and, in turn, leading to sustainable management of water resources in the study watershed. Copyright © 2016 John Wiley & Sons, Ltd.

Globally shaded leaves contribute to more than a half of the total increase in gross primary production (GPP; 7.6 Pg C) for 1982–2016. During 1982–2016, the fraction of shaded GPP increases by 1.1% (p < 0.01) in tropical forests and decreases by 1.4% (p < 0.01) and 1.8% (p < 0.01) in evergreen needleleaf and deciduous needleleaf boreal forests, respectively, suggesting an ecological niche of certain canopy structure for ecosystems to achieve maximum GPP. Unlike transpiration from sunlit leaves that has a turning point in the trend in 2003, global transpiration from shaded leaves steadily increased at the rate of 34 km3/year (p < 0.0001) during 1982–2016. Our study therefore suggests that shaded leaves have an increasing role in buffering the adverse impact of climate change and extremes. Further studies are still needed to reduce the uncertainties in reported trends arisen from climate forcing data, leaf area index, and land cover and land change products.

Aims To explore the role of self‐efficacy (SE) in the effect of patient empowerment on self‐management behaviours among patients with chronic illness and to investigate the moderating effect of three types of health locus of control (HLC) in this moderated mediation model. Design Cross‐sectional design. Methods Data were collected in a general tertiary hospital, and a sample of 254 patients was recruited between August and October 2020. The effect of moderation and mediation was tested by the PROCESS macro (Model 4 and Model 8) for SPSS 25.0 by Hayes using 5000 bootstrap samples. Results Self‐efficacy significantly mediated the relationship between patient empowerment and self‐management behaviour with a 95% confidence interval excluding zero. The chance HLC demonstrated a moderating effect, and the interaction effect on SE and self‐management behaviour was significant. Conclusion Patient empowerment may improve confidence and adherence to self‐management among people with chronic illness, and such benefits were conditional on the HLC of patients. Impact This study addresses the relationship between patient empowerment and self‐management behaviour in patients with different personality characteristics. This result indicated that classifying the type of HLC may enable the identification of subgroups of patients who may subsequently benefit from patient empowerment. In a patient‐centred programme, nurses and other healthcare professionals correctly identifying patients’ HLC type and understanding the implications and then providing appropriate health care plans for patients with different health beliefs may be useful to tailor the decision‐making process.

Using precipitation data from weather stations in China and reanalysis data from National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR), the inter‐annual and inter‐decadal variability of early‐summer (May–June) and late‐summer (July–August) precipitation (hereinafter referred to as MJP and JAP, respectively) over northeast China (NEC) and their background circulation during 1951–2016 were analysed. The following new findings have been highlighted: (a) There are significantly different inter‐annual and inter‐decadal variability characteristics between MJP and JAP over NEC. The inter‐annual variability of MJP is independent from that of JAP, while the inter‐decadal variability of the former is opposite to that of the latter. A significant shift to more MJP (less JAP) occurred in the early 2000s (late 1990s). (b) In terms of the inter‐annual timescale, the large‐scale atmospheric circulations‐associated MJP is notably different from JAP over NEC. The variation in MJP is mainly dominated by the northeast China low (NECL) and the Okhotsk blocking high (OBH), while JAP is mainly influenced by the western Pacific subtropical high (WPSH), the NEC south wind (NESW), and the NECL. (c) On the inter‐decadal timescale, MJP is associated with the inter‐decadal variation of the East Asia/Pacific (EAP) teleconnection, while JAP is closely related to the inter‐decadal variation of the NECL and NESW. When the EAP is in a positive phase, MJP is more than average. Furthermore in late summer, the strong NECL and NESW are both of benefit to the convergence of water vapour from the tropical southwest and East Asian subtropical westerlies over NEC, which contributes to the more JAP than average.

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Social responses to climate change over human history have been widely discussed in academia over the last two decades. However, the transformation of the human–environment nexus crossing prehistoric and historic periods and the processes associated with it are not yet clearly understood. In this study, based on published works on radiocarbon dating, archaeobotany, zooarchaeology, and archaeological sites, together with a synthesis of historical documents and high‐resolution paleoclimatic records, we trace the extent to which human settlement patterns in the Hexi Corridor in northwestern China evolved in conjunction with climate change over the last 5,000 years. A total of 129 Neolithic, 126 Bronze Age, and 1,378 historical sites in the Hexi Corridor (n=1,633) were surveyed. Our results show that, in the Late Neolithic and Bronze Age periods (~2800–100 BC), climate change contributed to the transformation of subsistence strategies and the subsequent changes in human settlement patterns in the Hexi Corridor. The warm‐humid climate in ~2800–2000 BC promoted millet agriculture and helped the Majiayao, Banshan, and Machang Cultures to flourish. The cold‐dry climate in ~2000–100 BC resulted in the divergence and transformation of subsistence strategies in the Xichengyi–Qijia–Siba and Shajing–Shanma Cultures and in a shift in their settlement patterns. However, in the historical period (121 BC–AD 1911), human settlement patterns were primarily determined by geopolitics related to the alternating rule of regimes and frequent wars, especially in the Sui–Tang dynasties. We also find that trans‐Eurasian cultural exchange since ~2000 BC improved social resilience to climate change in the Hexi Corridor, mediating the human–environment nexus there. Our findings may provide insights into how human societies reacted to climate change in arid and semi‐arid environments over the long term.

The introduction of wheat into China between ~4500 and 4000 cal. a BP is thought to have restructured the ancient Chinese agricultural system and contributed to the formation and development of Chinese civilization. However, the spatial variation in agricultural development before and after the introduction of exotic crops across the Yellow River valley has not yet been discussed in detail. Here, we report new archaeobotanical data and radiocarbon dates from 25 sites in Sanmenxia, Henan Province, which was a hub for human migration in the middle reach of the Yellow River. Integrating our data with those of other archaeobotanical studies in northern China confirms that spatial cropping patterns in the Yellow River valley changed significantly around 4000 cal. a BP in the context of trans-Eurasia exchanges. From 7000 to 4000 cal. a BP, millet crops in the upper and middle Yellow River valley dominated the agricultural system, while mixed millet and rice agriculture developed in the lower Yellow River valley. In the subsequent period (4000–2200 cal. a BP), the cropping system in the upper Yellow River valley changed predominantly to barley and wheat agriculture, supplemented with millets. The contemporaneous cropping system in the middle and lower Yellow River valley, however, was dominated by millets, supplemented with wheat and rice. We argue that technological innovation and its dissemination in the context of trans-Eurasian cultural exchanges provided the basis for changes in the agricultural systems in northern China during the Bronze Age. Additionally, the trajectory of agricultural development was influenced by the natural environment and social change in different regions of the Yellow River valley.