A 4D sedimentological approach to reconstructing the flood frequency and intensity of the Rhône River (Lake Bourget,NW European Alps)

A high-resolution sedimentological study of Lake Bourget was conducted to reconstruct the flood frequency and intensity (or magnitude) in the area over the last 350 years. Particular emphasis was placed on investigating the spatio-temporal distribution of flood deposits in this large lake basin. The thicknesses of deposits resulting from 30 flood events of the Rhône River were collected over a set of 24 short sediment cores. Deposit thicknesses were compared with instrumental data for the Rhône River discharge for the period from 1853 to 2010. The results show that flood frequency and intensity cannot be reliably reconstructed from a single core because of the inhomogeneous flood-deposit geometry in such a large lake. From all documented flood-deposit thicknesses, volumes of sediment brought into the lake during each flood event were computed through a Kriging procedure and compared with the historical instrumental data. The results show, in this study, that reconstructed sediment volumes are well correlated to maximal flood discharges. This significant correlation suggests that the increase of embankment and dam settlements on the Rhône River during the last 150 years has not significantly affected the transport of the smallest sediment fraction during major flood events. Hence, assessment of the flood-sediment volumes deposited in the large Lake Bourget is the only way to reliably reconstruct the flood frequency and intensity.     

Impact of radiations on the long-range correlation of soil moisture: A case study of the A’rou superstation in the Heihe River Basin

Journal of Geographical Sciences - Analyses of the soil moisture evolution trend and the influence of different types of radiation on soil moisture are of great significance to the simulation and...     

Towards a potential research agenda to guide the implementation of Spatial Data Infrastructures—A case study from India

Recently, Spatial Data Infrastructures (SDIs) has been a rapidly expanding field and broadly assumed to underpin the development of information society and the knowledge economy. In this paper, we argue that the anticipated benefits of SDIs have largely not yet been generally realized in practice due to a lack of a robust theoretical framework as well as insufficient empirical research to guide the implementation efforts. We posit that learnings from the allied discipline of Information Infrastructures, which has matured during the 1990s in response to the proliferation of distributed, complex, and heterogeneous networked systems, can provide a useful theoretical lens to inform the emerging domain of SDIs. We focus on three key concepts identified in the domain of information infrastructure theory, viz. the installed base, reflexive standardization, and cultivation approach to design, to develop a theoretical framework, which is then applied to analyse the ongoing initiative to establish National Spatial Data Infrastructure (NSDI) in India. This analysis helps us to provide the basis to articulate a potential research agenda—for both theory and practice—which, we believe, offers the promise to better conceptualize and implement SDIs, particularly in developing country settings like India.     

Impact of climate change on the surface water of Kaidu River Basin

To reveal the changing trend and annual distribution of the surface water hydrology and the local climate in the Bayanbuluk alpine-cold wetlands in the past 50 years, we used temperature, precipitation, different rank precipitation days, evaporation, water vapor pressure, relative humidity, dust storm days and snow depth to analyze their temporal variations. We conclude that there were no distinct changes in annual mean temperature, and no obvious changes in the maximum or minimum temperatures. Precipitation in warm season was the main water source in the wetlands of the study area and accounted for 92.0% of the annual total. Precipitation dropped to the lowest in the mid-1980s in the past 50 years and then increased gradually. The runoff of the Kaidu River has increased since 1987 which has a good linear response to the annual precipitation and mean temperature in Bayanbuluk alpine-cold wetland. Climate change also affected ecosystems in this area due to its direct relations to the surface water environment.     

Sources and transport of organic carbon from the Dongjiang River to the Humen outlet ofthe Pearl River,southern China简

Transport of organic carbon via rivers to estuary is a significant geochemical proc- ess in the global carbon cycle. This paper presents bulk total organic carbon （TOC） from the Dongjiang catchment to the adjacent Humen outlet, and discusses the applicability of 613C and ratio of carbon to nitrogen （C/N） as indicators for sources of organic matter in the surface sediments. Survey results showed that organic carbon concentration in summer were higher than in the winter. An elevated trend of TOC occurred along the river to the Humen outlet in both surveys, and the highest mean values of dissolved and particular organic carbon （DOC-279 μmol L-1 and POC-163μmol L-1） were observed in the urban deltaic region in summer flood flow. Winter samples had a wide range of b＇13C and C/N （5-3C -24.6%o to -30.0%o, C/N 4-13）, and summer ones varied slightly （8-3C -24.2%o to -27.6%0, C/N 6-18）. As results suggest that POC in the three zones of upstream-delta-outlet dominantly came from riverbank soil, phytoplankton and agricultural C3 plants in winter, whereas main sources were from the riverbank and mangrove soil in summer. Moreover, anthropogenic sewage inputs had 11% and 7% contribution to POC in the deltaic and outlet. Transport accompanied with seasonal freshwater variation, phytoplankton production and degradation, and removal be- havior caused variation of organic carbon concentration. The results also discovered that TOC export bulk in Dongjiang was approximately one quarter of Humen flux in the dry flow, and anthropogenic activity significantly impacted the river export contribution.     

Spatiotemporal mismatch of land use functions and land use efficiencies and their influencing factors:A case study in the Middle Reaches of the Yangtze River,China

Identification of the spatial mismatch between land use functions(LUFs) and land use efficiencies(LUEs) is essential to regional land use policies. However, previous studies about LUF-LUE mismatch and its driving factors have been insufficient. In this study, we explored the spatiotemporal mismatch of LUFs and LUEs and their influencing factors from 2000 to 2018 in the Middle Reaches of the Yangtze River(MRYR). Specifically, we used Spearman correlation analysis to reveal the trade-off relations...     

The cultural approach and geography ‐ the perspective of communication

An interest in culture developed in human geography from its beginning. It was rooted in a conception of 'geography as a science of places, not of men' (Vidal de la Blache), and focused on the study of man/milieu relationships through the analysis of landscapes or genres de vie , the origin and dispersal of agriculture, and the regional diversity of the earth. A neo-Weberian orientation appeared in the 1960s, but the main shift occurred in the 1970s, with the adoption of phenomenological or critical perspectives. The new cultural approach modernises the traditional orientations in the field, explores the meaning that people give to their spatial experience, and introduces new questions about the epistemological foundations of geography as a scientific discipline. In order to understand how society is produced and reproduced and how significance is given to the world, the new approach stresses the role of communication in cultural processes and spatial organisation.     

A study of the contribution of mass elevation effect to the altitudinal distribution of timberline in the Northern Hemisphere简

Alpine timberline, as the ＂ecologica tion of scientists in many fields, especially in transition zone,＂ has long attracted the atten- recent years. Many unitary and dibasic fitting models have been developed to explore the relationship between timberline elevation and latitude or temperature. However, these models are usually on regional scale and could not be applied to other regions; on the other hand, hemispherical-scale and continental-scale models are usually based on about 100 timberline data and are necessarily low in precision. The present article collects 516 data sites of timberline, and takes latitude, continentality and mass elevation effect （MEE） as independent variables and timberline elevation as dependent variable to develop a ternary linear regression meteorological data released by WorldClim and model. Continentality is calculated using the mountain base elevation （as a proxy of mass elevation effect） is extracted on the basis of SRTM 90-meter resolution elevation data. The results show that the coefficient of determination （R2） of the linear model is as high as 0.904, and that the contribution rate of latitude, continentality and MEE to timberline elevation is 45.02% （p=0.000）, 6.04% （p=0.000） and 48.94% （p=0.000）, respectively. This means that MEE is simply the primary factor contributing to the elevation distribution of timberline on the continental and hemispherical scales. The contribution rate of MEE to timberline altitude dif- fers in different regions, e.g., 50.49% （p=0.000） in North America, 48.73% （p=0.000） in the eastern Eurasia, and 43.6% （p=0.000） in the western Eurasia, but it is usually very high.     

Game strategies in government-led eco-compensation in the Xin’an River Basin from the perspective of the politics of scale

China's policy on ecological compensation (eco-compensation) in watershed eco-systems is of economic,social and environmental significance for China's ecological gov-ernance and protection of natural areas.It involves balancing the interests of regional stakeholders,coordinating the development of regional environments and establishing effec-tive cooperation models,making it a classic topic for geographical research.This study in-troduces the concept of institutional "stickiness" to the theory of politics of scale to analyze the features and mechanisms of the game behavior of government entities in the process of im-plementing watershed eco-compensation in the Xin'an River Basin.Our results show the following:government entities at various levels,including the central,provincial and municipal governments,experienced the three stages of game strategy of competition,cooperation and"coopetition";building a government community of shared interests can promote watershed eco-compensation,and "appropriate intervention" by the central govemment is key to achieving inter-provincial watershed eco-compensation;there was clear institutional stickiness during the transition from a "vertical" model of watershed eco-compensation to a "vertical-horizontal"model,with government entities using policy innovations and social participation to limit and reduce stickiness so as to reshape the watershed eco-compensation system;scalar jumping is the core mechanism that promoted eco-compensation in the study basin,and government entities shaped the discourse on watershed eco-compensation by redistributing powers and capital and creating informal constraints,which promoted the transformation of eco-compensation from a "strong state-weak society" structural model,to a "strong state-strong society" model in the Xin'an River Basin.These results can provide theoretical support for the construction of inter-regional watershed eco-compensation mechanisms,pro-vide a scientific basis for the rational evaluation and guidance of watershed eco-compensation practices,and promote the coordinated and sustainable socioeconomic development of watersheds.     

The coastal erosion and evolution of the Yellow River Delta abandoned lobe

1IntroductionThe river deltas are generally those areas with a wealth of natural resources, and lots of ports, moreover they are important locations of human activity. Therefore, deltaic areas around the world, such as the Mississippi River delta, the Nile River delta, and the Yangtze River delta, have attracted the attentions of governments, scientists and common people. There are three big deltas in China, i.e., the Yangtze River, the Zhujiang River and the Yellow River deltas. The for…     

The application of GPR to barrier-lagoon sedimentation study in Boao of Hainan Island

Sedimentary successions and internal structure of the coastal barrier-lagoon system of Boao, eastern Hainan Island were studied through utilizing data from test holes and trenches and ground-penetrating-radar (GPR) profiles. During late Pleistocene, fluvial and delta plains developed over an unevenly eroded bedrock during low sea level stand, followed by the formation of littoral and lagoon facies and defined coastal barrier-lagoon-estuary system during the post-glacial uppermost Pleistocene-lower Holocene eustatic rise of the sea level, and the upper Holocene high stand. GPR results show that Yudaitan, a sandy coastal bar backed by a low-laying land (shoal) just east of the active lagoon, is a continuous, parallel and slightly-wavy reflectors indicating homogeneous sandy or sandy gravel sediments, and inclined reflectors partly caused by progradation and accumulation of beach sand and gravel. Quasi-continuous, hummocky and chaotic reflectors from the shoal of Nangang village correspond to mixed accumula     

Water quantity-quality combined evaluation method for rivers＇ water requirements of the instream environment in dualistic water cycle： A case study of Liaohe River Basin

In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed, and compared with the meaning of unitary water cycle. Based on the analysis of the relationship between environmental flows of river requirements, the efficiency of water resource usage, the consumption coefficient, and the concentration of waste water elimination, the water quantity and water quality calculation method of the environmental flows of river requirements in dualistic water cycle is developed, and the criteria for environmental flows of river requirements are established, and therefore the water quantity-quality combined evaluation of natural river flows requirements are realized Taking the Liaohe River as a model, the environmental flows of river requirements for Xiliao River, Dongliao River, mainstream Liaohe River, Huntai River and northeast rivers along the coasts of the Yellow and Bohai seas in unitary water cycle are calculated, each taking up 39.3%, 63.0%, 43.9%, 43.3% and 43.5% of runoff respectively. Evaluated according to Tennant recommended flow, the results show that： except Xiliao River is ＂median＂, the rest are all upon ＂good＂, the Dongliao River is even ＂very good＂. The corresponding results in dualistic water cycle are that, the proportion of natural flows for each river is 57.5%, 74.1%, 60.8%, 60.3% and 60.4%; while the combined evaluation results show that： considering ＂quantity＂, except Xiliao River, the rest rivers can all achieve the ＂quantity＂ criteria of the en- vironmental flows of river requirements, but if considering the aspect of ＂quality＂, only Dongliao River can reach the ＂quality＂ standard. By water quantity-quality combined evaluation method, only Dongliao River can achieve the criteria. So the water quality is the main factor that determines whether the environmental flows can meet the river ecosystem demands.     

Habitat specificity can blur the predictions of species–energy theory: A case study of tenebrionid beetles adapted to aridity

Species–energy theory predicts a positive relationship between species richness and energy. The mechanism assumed by this theory is that high energy promotes high population abundance, which in turn promotes high species richness. Evaluations of this mechanism have rendered conflicting evidence, suggesting that more effort is needed to understand the theory’s limitations. Several studies have addressed these limitations, contributing to expand the theory’s scope by incorporating energy variation, whereas others have demonstrated scale dependence of the more individuals hypothesis. We propose that another limitation of this theory is related to its application to groups of species with strong habitat specificity. We suggest that the expected relationship between energy and richness is not necessarily positive at large scales for groups of species adapted to harsh environments. Using data on tenebrionid beetles from arid areas of southern South America, we contrasted four hypotheses that lead to contrasting predictions about the strength and direction of the species–energy relationship on tenebrionid richness. We found a negative relationship between richness and energy availability. We propose that this negative relationship is the result of a constraint in the mechanisms assumed by species?energy theory because organisms evolve adaptations to survive climatic harshness, which influences population abundances.     

The Application of Basement Tectonic Research to the Development of Natural Resources—Example Midcontinent North America

An understanding of an area in four dimensions is an important factor in utilizing our natural resources. The additional aspect of change through time, particularly the tectonic processes that have shaped the architecture of an area, can influence the interpretation of the origin and characterization of a resource. An example is provided of the influence that the patterns created during the formation of the continent in central North America demonstrates the continued influence of the original tectonic features and how they have persisted through time. It is this persistence and rejuvenation, that has controlled the occurrence of many of the natural resources on which we depend. Other references are provided to specific examples of the relationships between tectonics, particularly within the crystalline basement rocks, and our natural resource system.     

A Review of “The Geography of Bliss: One Grump's Search for the Happiest Places in the World”

In contrast to the conventional gravity model that estimates flows between cities of given sizes, the reverse gravity model attempts to reconstruct the theoretical gravitational attractions of cities from network flow data. This article introduces the particle swarm optimization (PSO) method in solving the reverse gravity model. With comparison to the linear programming (LP) and the simplified algebraic method (SAM), the advantages of the PSO method include flexibility in the impedance function and better goodness of fit. The method is applied to the case study of air passenger transport in China. The results indicate that estimated nodal attractions in cities are generally in line with their population sizes, but there are significant discrepancies between them. A close examination of the discrepancies reveals that a better developed tertiary sector and higher tourism revenue per capita are associated with overestimated attractions in air transport, and stronger railway dominance influences their underestimation. The changes of gravitational attractions in major cities from 2001 to 2008 indicate the declining dominance of the largest cities and a move toward a more balanced development in the air transport system of China.     

Mediterranean cities under fire. A critical approach to the wildland–urban interface

Wildfires are widely reviewed as key inputs to Mediterranean ecosystems. However, research is often flawed by major biases. (1) The approach adopted by most planners focusing on forest fires dismisses the human dimension of fire as a component of agricultural production systems. (2) The Wildland–Urban Interface (WUI) concept postulates that cities and wildlands/wildfires are, and should remain, worlds apart, a statement whose truth is increasingly questioned by recent disastrous “urban wildfires”. (3) The Mediterranean Basin as a fire-prone area is all the more fantasized, as it is almost never studied as a whole.The present paper takes a critical view of city–wildland/wildfire interrelationships through a large-scale study of the Mediterranean Basin based on MODIS MCD12Q1 (Land Cover Type) and MCD45A1 (Burned Area Product) data collected between 2001 and 2013. The Mediterranean is an ideal place to investigate, as its human-dominated and urbanized landscapes are known to be extremely vulnerable to fire hazards. Data processing reveals that (wild)fires and cities maintain indissoluble ties, as if both elements could not be considered mutually exclusive on a geographical basis. Urban sprawl, reduced rural autonomies, changes in forest covers, old agricultural practices, and military conflicts provide the framework for an extended mitigation process challenging the WUI concept as a space divider.     

Uncertainties in the geographic context of health behaviors: a study of substance users’ exposure to psychosocial stress using GPS data

ABSTRACT

This study examined how contextual areas defined and operationalized differently may lead to different exposure estimates. Substance users’ exposures to environmental stress (in terms of two variables: community social economic status and crime) were assessed from global positioning systems (GPS) data. Participants were 47 outpatients with substance use disorders admitted for methadone maintenance at a research clinic in Baltimore, Maryland. From 35.2 million GPS tracking points, we compared 7 different methods for defining activity space. The different methods yielded different exposure estimates, which would lead to different conclusions in studies using only one method. These results have important implications for future research on the effect of contextual influences on health behaviors and outcomes: whether a study observes any significant influence of an environmental factor on health may depend on what contextual units are used to assess individual exposure.     

Shaking and splashing—A case study of far-field effects of the Mjølnir asteroid impact on depositional environments in the Barents Sea

The Mjølnir impact crater in the Norwegian Barents Sea features among the 20 largest impact craters listed in the Earth Impact Database. The impact is dated to 142 ± 2.6 Ma, corresponding closely to the Jurassic/Cretaceous boundary in the Boreal stratigraphy. Multidisciplinary studies carried out over the last three decades have suggested that the up to 40 km wide crater was created by a 1–3 km diameter impactor colliding with a shallow epicontinental sea, causing regional havoc and a regional ecological crisis that followed in its wake. Only minor evidence for the consequences of the impact for the surrounding depositional basins has been documented so far. This study describes a large submarine slump penetrated by hydrocarbon exploration well 7121/9-1, located in the southern Hammerfest Basin and approximately 350 km away from the impact site. The slump is dated by a black shale drape, which contains characteristic impact-related biotic assemblages and potential ejecta material. This precise dating enables us to associate the slump with large-scale fault movements and footwall collapse along the basin-bounding Troms-Finnmark Fault Complex, which we conclude were caused by shock waves from the Mjølnir impact and the passage of associated tsunami trains. The draping black shale is interpreted to represent significant reworking of material from the contemporary seabed by tsunamis and currents set up by the impact.     

The Northern Myth Revisited? Aborigines,environment and agriculture in the Ord River Irrigation Scheme,Stages One and Two

Western Australia's Ord River Irrigation Scheme has been controversial since its establishment more than twenty-five years ago. A substantial expansion of the scheme, known as Ord Stage Two, is currently underway as a joint project of the Western Australian and Northern Territory governments. In this study I examine and compare Stages One and Two in the context of the significant social and economic changes that have occurred during this period, focusing on attitudes to, and conceptualisations of, nature and the human place in it. Despite a context in which consideration of both Aboriginal and environmental issues is now integrated into the development process, three colonial themes persist in the rhetoric of Stage Two. These are the empty landscape, the invisible Aborigine, and the idealisation of agricultural land use. When expressed together these three help to naturalise the development process as both inevitable and strategically implemented. The contradictions inherent in this process enhance existing doubts about the social and ecological sustainability of continuing attempts to 'develop' Australia's north.     

Precipitation cycles in the middle and lower reaches of the Yellow River （1736-2000）

Based on the long-term precipitation series with annual time resolution in the middle and lower reaches of the Yellow River and its four sub-regions during 1736-2000 reconstructed from the rainfall and snowfall archives of the Qing Dynasty, the precipitation cycles are analyzed by wavelet analysis and the possible climate forcings, which drive the precipitation changes, are explored. The results show that： the precipitation in the middle and lower reaches of the Yellow River has inter-annual and inter-decadal oscillations like 2-4a, quasi-22a and 70-80a. The 2-4a cycle is linked with El Nino events, and the precipitation is lower than normal year in the occurrence of the El Nino year or the next year; for the quasi-22a and the 70-80a cycles, Wolf Sun Spot Numbers and Pacific Decadal Oscillation （PDO） coincide with the two cycle signals. However, on a 70-80a time scale, the coincidence between solar activity and precipitation is identified before 1830, and strong （weak） solar activity is generally correlated to the dry （wet） periods; after 1830, the solar activity changes to 80-100a quasi-century long oscillation, and the adjusting action to the precipitation is becoming weaker and weaker; the coincidence between PDO and precipitation is shown in the whole time series. Moreover, in recent 100 years, PDO is becoming a pace-maker of the precipitation on the 70-80a time scale.