Contrasting Altitude and Long-term Geographical Isolation Shaped Phylogeography of Himalrandia  lichiangensis, an Endemic Species from the Dry Hot Valley of Southwest China

Author(s):  
Yaomei Qiao ◽  
Jian Liu ◽  
Xun Gong

Abstract Background: The eastern Sino-Himalayan region of southwest China, as one of the world’s biodiversity hotspots, has undergone dramatic geomorphological and climatic changes during the Late Tertiary/Quaternary. The dry-hot valleys in southwest China is overlapping with the Hengduan Mountains. However, when this endemism was assembled in dry-hot valleys and how the climatic oscillations and/or tectonic movements influence their phylogeographical patterns remained largely unknown. Himalrandia lichiangensis is a shrub of Rubiaceae, endemically distributes in dry-hot valleys of southwest China. By integrating evidences from phylogeography, population dynamic and ecological niche modelling, we are aiming to trace the evolutionary history and explain the origin of biodiversity and endemism in the dry-hot valleys of southwest China. Results: Based on sequencing four chloroplastic non-coding regions (psbM-trnD, trnD-trnT, atpB-rbcL and accD-psaI) and two single-low copy nuclear genes CAMX (Calmodulin) and ITS of 423 individuals from 23 populations, we found high genetic variation mainly existed between the populations (cpDNA: 89.80%, ITS: 84.55%, CAMX: 95.68%). Haplotypes in different river basins showed significant phylogeographical structure. The geographical distribution of haplotypes indicated that there is a high degree of genetic differentiation and this differentiation is associated with altitude discrepancy. BARRIER analysis detects a strong geographic barrier between the Nanpan River and Jinsha River. The MaxEnt result shows that the suitable distribution area was the largest in the LGM. The future climate warming will lead to the niche expansion for H. lichiangensis but will also cause fragmented distribution.Conclusions: Our study highlighted the importance of altitude in explaining the genetic differentiation. The current phylogeographical pattern of H. lichiangensis may be shaped by long-term geographical isolation resulted from the uplifting of Himalaya, which gives rise to the barriers from the Hengduan Mountain or multiple river systems, and the vertical altitude discrepancies that both limited gene flow among regions. The Middle Jinsha River valley is most likely to be a main refuge for H. lichiangensis till now, and the glaciation retreat may account for the high endemism of plants in the dry-hot valleys of southwest China.

2004 ◽  
Vol 359 (1442) ◽  
pp. 265-274 ◽  
Author(s):  
Joachim W. Kadereit ◽  
Eva Maria Griebeler ◽  
Hans Peter Comes

Molecular clock approaches applied previously to European alpine plants suggest that Primula sect. Auricula , Gentiana sect. Ciminalis and Soldanella diversified at the beginning of the Quaternary or well within this period, whereas Globularia had already started diversifying in the (Late–)Tertiary. In the first part of this paper we present evidence that, in contrast to Globularia and Soldanella , the branching patterns of the molecular internal transcribed spacer phylogenies of both Primula and Gentiana are incompatible with a constant–rates birth–death model. In both of these last two taxa, speciation probably decreased through Quaternary times, perhaps because of some niche–filling process and/or a decrease in specific range size. In the second part, we apply nonlinear regression analyses to the lineage–through–time plots of P. sect. Auricula to test a range of capacity–dependent models of diversification, and the effect of Quaternary climatic oscillations on diversification and extinction. At least for one major clade of sect. Auricula there is firm evidence that both diversification and extinction are a function of temperature. Intriguingly, temperature appears to be correlated positively with extinction, but negatively with diversification. This suggests that diversification did not take place, as previously assumed, in geographical isolation in high–altitude interglacial refugia, but rather at low altitudes in geographically isolated glacial refugia.


2008 ◽  
Vol 20 (3) ◽  
pp. 409-450 ◽  
Author(s):  
James N. Stanford

AbstractSui clan exogamy can serve as a laboratory for investigation of dialect contact and immigration. The Sui people, an indigenous minority of southwest China, have marriage customs requiring that a wife and husband have different clan origins, and the wife permanently immigrates to the husband's village at the time of marriage. Due to subtle interclan dialect variation, a married woman may have different dialect features than her husband and other local villagers. This study presents an acoustic analysis of such clan-level variation in lexical tone, asociotoneticanalysis. Results show that the immigrant women maintain the tone variants of their home clan dialects to a high degree despite spending a decade or more in the husband's village, thus illustrating a case where linguistic identity is maintained in the face of close, long-term contact.


Water ◽  
2018 ◽  
Vol 10 (2) ◽  
pp. 235 ◽  
Author(s):  
Yu Feng ◽  
Jianzhong Zhou ◽  
Li Mo ◽  
Zhe Yuan ◽  
Peilun Zhang ◽  
...  

2021 ◽  
pp. 088626052098781
Author(s):  
Marin R. Wenger ◽  
Brendan Lantz

Prior research suggests that many crime types are spatially concentrated and stable over time. Hate crime, however, is a unique crime type that is etiologically distinct from others. As such, examination of hate crime from a spatial and temporal perspective offers an opportunity to understand hate crime and the spatial concentration of crime more generally. The current study examines the spatial stability of hate crimes reported to the police in Washington, D.C., from 2012 through 2018 using street segments, intersections, and block groups as units of analysis. Findings reveal that hate crime is spatially concentrated, with less than 4% of street segments and intersections experiencing hate crime over the study period. Results reveal a high degree of spatial stability, both year-to-year and over the long term even when restricting the analysis to units that experienced at least one hate crime.


Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 903 ◽  
Author(s):  
Ivan Trifonov ◽  
Dmitry Trukhan ◽  
Yury Koshlich ◽  
Valeriy Prasolov ◽  
Beata Ślusarczyk

In this study we aimed to determine the extent to which changes in the share of renewable energy sources, their structural complex, and the level of energy security in Eastern Europe, Caucasus and Central Asia (EECCA) countries in the medium- and long-term are interconnected. The study was performed through modeling and determination of the structural characteristics of energy security in the countries. The methodology of the approach to modeling was based on solving the problem of nonlinear optimization by selecting a certain scenario. For the study, the data of EECCA countries were used. The ability of EECCA countries to benefit from long-term indirect and induced advantages of the transformation period depends on the extent to which their domestic supply chains facilitate the deployment of energy transformation and induced economic activity. This study provides an opportunity to assess the degree of influence of renewable energy sources on the level of energy security of countries in the context of energy resource diversification. The high degree of influence of renewable energy sources on energy security in the EECCA countries has been proven in the implementation of the developed scenarios for its increase. Energy security is growing. At the same time, its level depends not only on an increase in the share of renewable sources but also on the structure of energy resources complex of countries, and the development of various renewable energy sources. Therefore, today the EECCA countries are forced not only to increase the share of renewable energy sources but also to attach strategic importance to the structural content of their energy complex.


Author(s):  
Behnam Jahangiri ◽  
Punyaslok Rath ◽  
Hamed Majidifard ◽  
William G. Buttlar

Various agencies have begun to research and introduce performance-related specifications (PRS) for the design of modern asphalt paving mixtures. The focus of most recent studies has been directed toward simplified cracking test development and evaluation. In some cases, development and validation of PRS has been performed, building on these new tests, often by comparison of test values to accelerated pavement test studies and/or to limited field data. This study describes the findings of a comprehensive research project conducted at Illinois Tollway, leading to a PRS for the design of mainline and shoulder asphalt mixtures. A novel approach was developed, involving the systematic establishment of specification requirements based on: 1) selection of baseline values based on minimally acceptable field performance thresholds; 2) elevation of thresholds to account for differences between short-term lab aging and expected long-term field aging; 3) further elevation of thresholds to account for variability in lab testing, plus variability in the testing of field cores; and 4) final adjustment and rounding of thresholds based on a consensus process. After a thorough evaluation of different candidate cracking tests in the course of the project, the Disk-shaped Compact Tension—DC(T)—test was chosen to be retained in the Illinois Tollway PRS and to be presented in this study for the design of crack-resistant mixtures. The DC(T) test was selected because of its high degree of correlation with field results and its excellent repeatability. Tailored Hamburg rut depth and stripping inflection point thresholds were also established for mainline and shoulder mixes.


Author(s):  
Leijin Long ◽  
Feng He ◽  
Hongjiang Liu

AbstractIn order to monitor the high-level landslides frequently occurring in Jinsha River area of Southwest China, and protect the lives and property safety of people in mountainous areas, the data of satellite remote sensing images are combined with various factors inducing landslides and transformed into landslide influence factors, which provides data basis for the establishment of landslide detection model. Then, based on the deep belief networks (DBN) and convolutional neural network (CNN) algorithm, two landslide detection models DBN and convolutional neural-deep belief network (CDN) are established to monitor the high-level landslide in Jinsha River. The influence of the model parameters on the landslide detection results is analyzed, and the accuracy of DBN and CDN models in dealing with actual landslide problems is compared. The results show that when the number of neurons in the DBN is 100, the overall error is the minimum, and when the number of learning layers is 3, the classification error is the minimum. The detection accuracy of DBN and CDN is 97.56% and 97.63%, respectively, which indicates that both DBN and CDN models are feasible in dealing with landslides from remote sensing images. This exploration provides a reference for the study of high-level landslide disasters in Jinsha River.


Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 746
Author(s):  
Yifan Wang ◽  
Dengju Wang ◽  
Rong Zhao

To achieve the dual goal of poverty alleviation and ecological restoration, the policy of ecological forest rangers (EFRs) was implemented in rural poverty-stricken areas in China, where local residents commonly depend on nearby forest resources for livelihoods. This study aimed to analyze the short-term and long-term effectiveness of the EFRs policy in China mainly in poverty alleviation and income growth, with a brief discussion on the ecological effect of the policy. A questionnaire survey was conducted in four counties in the Karst rocky desertification region in southwest China. By combing through the early literature on REDD+, community forestry, leasehold forestry, etc., this paper summarizes the experience and lessons of similar community forest management models, aiming to explain the unsustainability of EFRs policy from the perspective of forest tenure and governance. The findings of the effectiveness analysis of EFRs policy in the four poverty-stricken counties reflect different degrees of effect in rural households with different income levels. We believe that the EFRs policy has played important roles in short-term regional poverty alleviation while its potential for long-term income growth has not been stimulated. For the amendment of EFRs policy, we put forward the following points: (1) It is necessary to redesign the selection and recruitment mechanism, as well as the exit mechanism of EFRs adapting to the local conditions. (2) It is advisable to further improve the local assessment and monitoring system of forest protection quality of EFRs and optimize the establishment of benefit linkage mechanism between protection effectiveness and EFRs remuneration. (3) The EFRs remuneration standards should be dynamically raised to assure the active participation of EFRs in forest protection. Furthermore, there is a need for one more effective integration model of forest protection and rural livelihoods improvement, which is considered as a potential future research direction.


2021 ◽  
pp. 205789112110192
Author(s):  
Peng Lin

Engaging in disaster relief and, more recently, post-disaster reconstruction in developing countries with critical geoeconomic and geopolitical interests has become an increasingly regular and institutionalized component of China’s evolving humanitarian diplomacy over the past decade. Drawn upon novel evidence from China’s growing disaster-related humanitarian assistance to Nepal and unprecedented engagement in Nepal’s long-term post-earthquake rebuild since 2015, this article explores the dynamics behind China’s transforming humanitarian diplomacy. The findings of this article suggest that: 1) geopolitical and geoeconomic interests, represented by the Belt-and-Road Initiative, serve as a critical driver for the development of China’s bilateral partnership with other countries in the disaster sector; 2) long-term cooperation with underdeveloped countries like Nepal provides China, both government and non-state actors (NSAs), with an effective channel to engage with the international humanitarian community and to internalize humanitarian norms; 3) although humanitarian missions remain contingent and instrumental in China’s international relations, they are laying the foundations for a specialized humanitarian policy area with more relevant normative assets, more professional actors, and more sophisticated institutions; 4) NSAs, represented by private foundations and civil NGOs, have played active roles in the state-dominant cooperation in disaster management. This article also suggests that intensified geopolitical confrontations, such as military clashes between India and China along their disputed borders over the past year, would lead to a high degree of politicization of humanitarian missions and partnerships counter-conducive to humanitarian goals.


Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 121
Author(s):  
Noriko Yamaguchi ◽  
Toshiaki Ohkura ◽  
Atsuko Hikono ◽  
Yohey Hashimoto ◽  
Aomi Suda ◽  
...  

Global concerns for the sustainability of agriculture have emphasized the need to reduce the use of mineral fertilizer. Although phosphorus (P) is accumulated in farmland soils due to the long-term application of fertilizer, most soil P is not readily available to plants. The chemical speciation of P in soils, which comprise heterogeneous microenvironments, cannot be evaluated with a high degree of specificity using only macroscopic analyses. In this study, we investigated the distribution and speciation of P accumulated in soils by using both macro- and microscopic techniques including chemical extraction, solution and solid-state 31P NMR, bulk- and micro- P K-edge X-ray absorption near edge structure (XANES), and electron probe microanalysis (EPMA). Soil samples were collected from a field in which cabbage was cultivated under three amendment treatments: i) mineral fertilizer (NPK), ii) mineral fertilizer and compost (NPK + compost), and iii) mineral fertilizer plus compost but without nitrogen fertilizer (PK + compost). Macro-scale analyses suggested that accumulated P was predominantly inorganic P and associated with Al-bearing minerals. The repeated application of compost to the soils increased the proportion of P associated with Ca which accounted for 17% in the NPK + compost plot and 40% in the PK + compost plot. At the microscale, hot spots of P were heterogeneously distributed, and P was associated with Fe and Ca in hot spots of the NPK + compost (pH 6) and PK + compost (pH 7) treated samples, respectively. Our results indicate that application of compost contributed to creating diverse microenvironments hosting P in these soils.


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