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The dominant influencing factors of changes in vegetation NPP and the relative roles of climate–human factors on the Qinghai–Tibet Plateau (QTP) differ between historical periods and are unclear. Therefore, there is an urgent need to systematically and quantitatively analyze the evolution process of the QTP’s ecosystem pattern and the driving factors of this process. Based on MOD17A3H and meteorological data, the Miami model, correlation analysis, and the residual coefficient method were used to investigate the spatiotemporal patterns of changes in vegetation NPP on the QTP from 2000 to 2020. We then quantitatively distinguished the relative roles of climate change and human activity in the process of vegetation NPP change during different historical periods. The results show the following: (1) From 2000 to 2020, zones with increasing vegetation NPP (10–30%) were the most widely distributed, and were mainly located in the Three-Rivers Headwater Region and the northern part of the Hengduan Mountains. (2) From 2000 to 2020, zones with a significant positive correlation between vegetation NPP and annual precipitation were mostly distributed in the northeastern QTP and the Three-Rivers Headwater Region, while zones with a positive correlation between vegetation NPP and annual average temperature were mostly located in southern Tibet. Zones with a significant positive correlation between NPP and annual sunshine hours were mainly distributed in the southeastern part of the QTP and the southern part of the Tanggula Mountains. In contrast, zones with a significant positive correlation between NPP and accumulated temperature (>10 °C) were mainly concentrated in the northern and eastern parts of the QTP. (3) During different historical periods, the relative roles of climate–human factors in the process of vegetation NPP change on the QTP had obvious spatiotemporal differences. These results could provide scientific support for the protection and restoration of regional ecosystems on the QTP.

Multi-scale contributions are involved in the South China Sea (SCS) summer monsoon (SCSSM) onset process. The relative roles of intraseasonal oscillation and above-seasonal component in the year-to-year variation of the SCSSM onset are evaluated in this study. The 30-90-day and above-90-day components are major contributors to the year-to-year variation of the SCSSM onset, and the former contributes greater portion, while the 8-30-day component has little contribution to the onset. In the early onset cases, the 30-90-day westerly winds move and extend eastward from the tropical Indian Ocean (TIO) to the SCS monsoon region relatively earlier, and replace the easterly winds over the SCS with the cooperation of the 30-90-day cyclone moving southward from northern East Asia. The westerly anomalies of the above-90-day component in spring jointly contribute to the early SCSSM onset. In the late onset cases, the late eastward expansion of 30-90-day westerly wind over the TIO, accompanied by the late occurrence and weakening of the 30-90-day anticyclone over the SCS, and its late withdraw from the SCS, as well as the persistent easterly anomalies of above-90-day component, suppress the SCSSM onset. However, the SCSSM outbreaks in the obvious weakening stage of 30-90-day easterly anomalies. The easterlies-to-westerlies transition of the 30-90-day 850hPa zonal wind over the SCS in spring is closely associated with sea surface temperature in the tropical western Pacific in preceding winter and spring, while the interannual variation of the above-90-day zonal wind in April-May is closely related to the decaying stage of the El Niño-Southern Oscillation events.

To overcome the shortcoming of existing studies, this paper put forward a statistical vegetation–climate relationship model with integrated temporal and spatial characteristics. Based on this model, we quantitatively discriminated on the grid scale the relative role of climate change and human activities in the desertification dynamics from 1986 to 2000 in Yulin region. Yulin region’s desertification development occurred mainly in the southern hilly and gully area and its reverse in the northwest sand and marsh area. This spatial pattern was especially evident and has never changed thoroughly. From the first time section (1986–1990) to the second (1991–1995), the desertification was developing as a whole, and either in the desertification development district or in the reverse district human activities’ role was always occupying an overwhelmingly dominant position (they were 98.7% and 101.4%, respectively), the role of climate change was extremely slight. From the second time section (1991–1995) to the third (1996–2000), the desertification process was reaching a state of stability, in the desertification development district the role of climate change was nearly equivalent to that of human activities (they were 46.2% and 53.8% separately), and yet in the desertification reverse district, the role of human activities came up to 119.0%, the role of climate change amounted to −19.0%. In addition, the relative role of climate change and human activities possessed great spatial heterogeneity. The above conclusion rather coincides with the qualitative analysis in many literatures, which indicates that this method has certain rationality and can be utilized as a reference for the monitoring and studying of desertification in other areas.

Climate change and human activities are driving forces of sandy desertification and the relative role of them in sandy desertification is the hot point in related researches. A study was carried to assess the relative role of climate change and human activities in sandy desertification of Ordos region in China. Potential NPP and the difference between potential and actual NPP were selected as indicators to assess the relative role of climate change and human activities in sandy desertification, respectively. Assessing methods were built based on some scenarios for the reversion and expansion of sandy desertification and the relative role of climate change and human activities in sandy desertification of Ordos region were assessed from 1981 to 2000. The results showed that although some local places experienced an expansion of sandy desertification, the change of sandy desertification of Ordos region from 1981 to 2000 showed a stably reversing trend. The relative role of climate change and human activities in sandy desertification of Ordos region varied at different temporal and spatial scales in the reversion and expansion processes. In the reversion of sandy desertification, climate change was the dominant factor in the period of 1981 to 1990 and the reversed areas mainly induced by climate change including Mu Us sandy land and the transition zone between temperate steppe and temperate deciduous scrubs in north east of Ordos region; however, human activities controlled the reversed process during the period from 1991 to 2000 and the areas mainly induced by human activities distributed in all banners of Ordos region. In the expansion of sandy desertification, human activities were the dominant factor in the period of 1981 to 1990 and the expanded areas mainly included the regions around common boundary of Hanggin, Dalad Banners and Dongsheng City; however, climate change dominated the expansion of sandy desertification from 1991 to 2000, the expanded areas equably distributed in the whole of Ordos region except the south east of Otog Qian, Uxin and Jungar Banners.

Climate change and human activities are the two kinds of driving forces in desertification, and assessing their relative role in desertification is of great significance to deeply understanding the driving mechanisms and preventing desertification expansion. This paper has systematically reviewed the progress of the researches on assessing the relative role of climate change and human activities in desertification from qualitative, semi-quantitative and quantitative aspects respectively. The authors found that there were still some problems in the previous researches. For example, the subjectivity in assessment was obvious, the assessment cannot be easily repeated, and the assessment and its results were always based on administrative regions and less taken and expressed in a continuous space. According to the progress of previous researches and the works conducted by the authors recently, we put forward a quantitative approach by selecting NPP as a common indicator to measure the relative role of climate change and human activities in desertification and dividing the ecological process of “driving force effect-dynamic response of desertified land” into several scenarios. Meanwhile, validation and scale of assessment should be taken into account when quantitative assessment of the relative role of climate change and human activities in desertification are carried out.

Recent studies have suggested that root-feeding nematodes influence plant community dynamics, but few studies have investigated the population dynamics of the nematodes. In coastal foredunes, feeding-specialist cyst nematodes (Heterodera spp.) are dominant in the soil nematode community and greenhouse studies pointed at bottom-up control by their host plant. Here we examine the population dynamics of H. arenaria in the field in relation to resource quantity in the root zone of Ammophila arenaria (marram grass). Ammophila arenaria is a pioneer grass in mobile coastal foredunes of northwestern and Mediterranean Europe. Every year, the plant expands clonally into freshly deposited layers of wind-blown sand, followed by dispersal and build-up of the nematode population into the new root zone. In a newly developing root zone the first H. arenaria cysts were observed one month after the first new roots were detected, indicating that nematode dispersal is not limiting the initial establishment of new populations. Throughout the growth season, the numbers of cysts, as well as the numbers of eggs and juveniles within cysts, were related to the quantity of roots. However, cyst density varied between years. Therefore, we conclude that in new root layers of A. arenaria cyst nematodes are bottom-up controlled by resource quantity, but that other factors, for example resource quality, influence the relation between nematode abundance and resource quantity. In deeper root zones the nematode abundance declines over time. Here, numbers of cysts were not related to root biomass, while numbers of eggs and juveniles inside the cysts were weakly related. This points at other factors than resource quantity, for example the quality of the roots or unsuitable abiotic environmental conditions that have a stronger influence on cyst numbers than resource quantity. We discuss how bottom-up control of cyst nematodes may indirectly protect the plant against harmful root knot nematodes.

This chapter contains sections titled: Abstract Introduction Failure Criteria in Pore Fluid Factor–Differential Stress Space Examples of λ–σ Failure Mode Diagrams Paths to Failure: The Relative Roles of Changes in Stress and Fluid Pressure States in Driving Failure and Permeability Regeneration Conclusions Acknowledgements References

This chapter contains sections titled: Overview and clinical significance Pathophysiology and risk factors Diagnosis Complications Management Prevention Follow‐up Conclusion Suggested reading

Objective The current study uses insights from the stress process model and role theory to examine the relationship between familial incarceration, three key social roles—spouse, parent, and employee—and African American women's mental health. Background Research documents the spillover effects of mass incarceration on the families of those incarcerated. Approximately half of black women have at least one family member currently incarcerated; yet the potential psychological costs of familial incarceration among black women remains under‐investigated, particularly among those who are not parents. Method Utilizing the National Survey of American Life, a nationally representative sample of never‐incarcerated African American women (N = 1,961), this study used regression to examine the association of mental health (measured by psychological distress and depressive symptomatology), familial incarceration, and combinations of social roles. Results Familial incarceration was associated with higher levels of depressive symptoms and psychological distress. Women that were employed only typically had improved psychological adjustment compared to other role combinations; yet, employment did not mute the mental health costs of familial incarceration. Conclusion African American women disproportionately experience the incarceration of family members, and the findings demonstrate that this experience is detrimental to mental health. Though social roles variably provide social, psychological, and economic resources to cope with familial incarceration, results show that the mental health costs of incarceration are generally consistent across role combinations. The expansive criminal justice system holds large implications for the well‐being of populations at the intersection of race, gender, and social roles.

Rank-order relative-performance evaluation, in which pay, promotion, symbolic awards, and educational achievement depend on the rank of individuals in the distribution of performance, is ubiquitous. Whenever organizations use rank-order relative-performance evaluation, people receive feedback about their rank. Using a real-effort experiment, we aim to discover whether people respond to the specific rank that they achieve. In particular, we leverage random variation in the allocation of rank among subjects who exerted the same effort to obtain a causal estimate of the rank response function that describes how effort provision responds to the content of rank-order feedback. We find that the rank response function is U-shaped. Subjects exhibit “first-place loving” and “last-place loathing”: that is, subjects work hardest after being ranked first or last. We discuss implications of our findings for the optimal design of performance feedback policies, workplace organizational structures, and incentives schemes. Data and the supplementary web appendix are available at https://doi.org/10.1287/mnsc.2017.2907 . This paper was accepted by Uri Gneezy, behavioral economics.