Kiribati: an environmental ‘perfect storm’

Recent environmental discourses and headlines on small island developing states (SIDS) have heralded the grave and impending threats of global warming and associated sea-level rise. These are undoubtedly significant challenges for SIDS, including atoll nations such as Kiribati. Nevertheless, securing small island state futures also requires a renewed commitment to addressing the obvious and immediate threats of urbanisation, pollution and sanitation. Looking at pressures of development on freshwater, this article argues that the future survival of small island states and their societies also greatly depends on managing the impacts of development. Approaches which can concurrently strengthen the resilience of communities and their ecosystems will result in mutual benefits for both sustainable development and climate change adaptation.     

Holocene precipitation δ18O as an indicator of temperature history in arid central Asia: an overview of recent advances

Holocene δ¹⁸O records from various archives (ice cores, cave stalagmites, and peat sediments) from the Xinjiang region of northwestern China, in arid central Asia (ACA), are all derived ultimately from local precipitation δ¹⁸O (δ¹⁸O_p). Nevertheless, they have been proposed as indicators of different climatic parameters, such as wetness and temperature changes. This article summarizes previously reported records of moisture sources for the Xinjiang region and the results of modern observations conducted at an ice core site and a peat site in the Altai Mountains. The findings are used to propose that the overall positive trends in Holocene δ¹⁸O records from the various archives from the Xinjiang region primarily reflect the Holocene's long-term warming trend. It is concluded that more site-specific modern observations are needed to further elucidate the environmental significance of Holocene δ¹⁸O records from this region, especially for the separation of different seasonal temperature signals present within δ¹⁸O records.     

Vulnerability and adaptation of an oasis social–ecological system affected by glacier change in an arid region of northwestern China

The Hexi Inland River Basin in an arid region of northwestern China was chosen as the study area for this research. The authors define the vulnerability of an oasis social-ecological system to glacier change; select 16 indicators from natural and socioeconomic systems according to exposure, sensitivity, and adaptive capacity; and construct a vulnerability-assessment indicator system aimed at an inland river basin in the arid region of Northwestern China. Vulnerability of the oasis socialecological system affected by glacier change in the study area is evaluated by Spatial Principal Component Analysis(SPCA) under the circumstance of glacier change. The key factors affecting the vulnerability are analyzed. The vulnerability of the oasis social-ecological system in the Hexi Inland River Basin affected by glacier change is of more than medium grade, accounting for about 48.0% of the total number of counties in the study area. In terms of the spatial pattern of the vulnerability, the oasis economic belt is the most vulnerable. With the rapid development of the area's society and economy, the exposure of the system to glacial changes is significantly increased; and an increase in glacial meltwater is not enough to overcome the impact of increased exposure, which is the main reason for the high vulnerability. Based on the result of the vulnerability analysis and combined with the present industrial structure in the Hexi Inland River Basin, near-,medium-, and long-term adaptation initiatives are put forward in the article.     

The potential model – an analysis of some methodological problems

Stokkan, J. The potential model – an analysis of some methodological problems. Norsk geogr. Tidsskr. 29, 111–132.

The article is concerned with operational problems of the potential model. In connection with a general discussion of operational problems, a base model is constructed. This model is applied to a study area in order to determine the model's sensitivity to the area of the analytical unit, the distance exponent, and distances within the unit. The analysis shows that the potential is to a large degree dependent upon the definition of these three factors.     

Cracking in an expansive soil under freeze–thaw cycles

Expansive soils located in cold regions can easily endure the action of frost heaving and cyclic freezing–thawing. Cracking can also occur in expansive clayey soils under freeze–thaw cycles, of which little attention has been paid on this issue.In this study, laboratory experiment and cracking analysis were performed on an expansive soil. Crack patterns were quantitatively analyzed using the fractal concept. The relationships among crack pattern, water loss, number of freeze–thaw cycles, and fractal dimension were discussed. It was found that crack patterns on the surface exhibit a hierarchical network structure that is fractal at a statistical level. Cracks induced by freeze–thaw cycles are shorter, more irregularly oriented,and slowly evolves from an irregularly rectilinear pattern towards a polygonal or quasi–hexagonal one; water loss, closely related to specimen thickness, plays a significant role in the process of soil cracking; crack development under freeze-thaw cycles are not only attributed to capillary effect, but also to expansion and absorption effects.     

What controls an earthquake's size? Results from a heterogeneous cellular automaton

The controls on an earthquake's size are examined in a heterogeneous cellular automaton that includes stress concentrations which scale with rupture size. Large events only occur when stress is highly correlated with strength over the entire fault. Although the largest events occur when this correlation is the highest, the magnitude of the correlation has no predictive value as events of all magnitudes occur during times of high stress/strength correlation. Rather, the size of any particular event depends on the local stress heterogeneity encountered by the growing rupture. Patterns of energy release with time for individual ruptures reflect this heterogeneity and many show nucleation-type behaviour, although there is no relation between the duration of nucleation phase and the size of the event. These results support the view that earthquake size is determined by complex interactions between previous event history and dynamic stress concentrations and suggest that deterministic earthquake prediction based on monitoring nucleation zones will not be possible.     

The harmonious relationship between land use and environment in Xi’an

1 Introduction Generally, it is the urbanization that causes the structural change of landscape environment, and the structure, scale, benefit and effectiveness of LUCC are all the spatial appearance and important results of Xi’an’s urbanization. It no…     

Metropolitan dynamics in Israel: an emerging “metropolitan island state”?

This study analyzes metropolitan dynamics in a small country with an “island state” context of closed boundaries, using commuting data and mobile phone tracking data. We examine whether the Israeli context encourages the formation of a monocentric “metropolitan state,” characterized by increasing links between localities throughout the country and its principal metropolitan node (Tel Aviv)—rather than with secondary metropolitan areas—and by fuzzy, overlapping metropolitan boundaries. Commuting data from the 1995 and 2008 censuses show that metropolitan expansion processes in Israel are gradual. Mobile phone tracking data for 2013 reveal similar patterns, confirming the urban structure’s stability and the reliability of tracking data as a means of assessing metropolitan processes. The “island state” context supports growing monocentricity, but, when it comes to commuting and travel for other purposes, Israel is not yet a metropolitan state; metropolitan boundaries are not as fuzzy and rapidly changing as expected.     

SPIDER—an interactive statistical tool for the analysis of spatially distributed data

Interactive statistical graphics are reviewed in the contexts of spatial data and geographical information systems (GIS). GIS provide the user with an active geographical view of the data—a map that can be used as an entry point to the data base. Prototype software—SPIDER—illustrates the possibilities of using statistical graphics as further views of the data, which can be made active and thus provide alternative means of querying the data. These views can be cross-referenced by 'linking'. It is argued that such a system can provide a very rich environment for pursuing exploratory statistical analysis of spatial data.     

Is there an observable lack of reciprocity in PKP(DF) traveltimes?

On average, traveltimes of PKP_DF for equatorial ray paths through the quasieastern hemisphere of the inner core are around 0.5 s faster than equivalent ray paths through its quasiwestern hemisphere. In these observations, the eastern hemisphere is sampled primarily by westward and the western hemisphere by eastwardpropagating waves. Noting that westward propagation is faster than eastward propagation inside a rotating earth, I estimate the expected traveltime difference from Coriolis splitting of the displacement eigenfunctions of the PKP_DF equivalent modes. It turns out that Coriolis effects are too small to give rise to residuals of the required magnitude. Thus, the observations must be primarily due to velocity heterogeneities.     

Observations of the Drainage of an Ice-Dammed Lake — Strupvatnet,Troms, Norway

The behaviour of the ice-dammed lake, Strupvatnet, Troms County, Norway, is described. Past observations are noted and related to observations in 1959 and to other ice-dammed lakes. Mechanisms for opening and maintaining water flow during a ‘hlaup’ are discussed. It is considered that Liestol's melt widening process operates after initiation by a pressure gradient across the dam. The lake and the internal drainage system of the glacier are thus linked. There is no evidence of lifting of the ice dam at Strupbreen.     

An Evaluation of an Object-Oriented Paradigm for Land Use/Land Cover Classification∗

Object-oriented image classification has tremendous potential to improve classification accuracies of land use and land cover (LULC), yet its benefits have only been minimally tested in peer-reviewed studies. We aim to quantify the benefits of an object-oriented method over a traditional pixel-based method for the mixed urban–suburban–agricultural landscape surrounding Gettysburg, Pennsylvania. To do so, we compared a traditional pixel-based classification using maximum likelihood to the object-oriented image classification paradigm embedded in eCognition Professional 4.0 software. This object-oriented paradigm has at least four components not typically used in pixel-based classification: (1) the segmentation procedure, (2) nearest neighbor classifier, (3) the integration of expert knowledge, and (4) feature space optimization. We evaluated each of these components individually to determine the source of any improvement in classification accuracy. We found that the combination of segmentation into image objects, the nearest neighbor classifier, and integration of expert knowledge yields substantially improved classification accuracy for the scene compared to a traditional pixel-based method. However, with the exception of feature space optimization, little or no improvement in classification accuracy is achieved by each of these strategies individually.     

Re-constructing the urban landscape through community mapping: an attractive prospect for sustainability?

Community mapping is a relatively new tool with considerable potential in giving practical effect at the local level to sustainable development rhetoric. As a repository of socially constructed knowledge, it has considerable value in democratizing information both in terms of what is recorded and public access to it, in a manner that facilitates more meaningful participation of non-experts in planning and advocacy processes. Focusing on a community mapping project in Galway, Ireland, this research paper explores how the city's municipal authority is employing community mapping not just to record and promote the city's social, environmental, economic and cultural assets but also as a practical tool to bolster public participation in policy-making and to improve local communities' trust in the municipal authority, thereby shaping sustainability practices through enhanced governance.     

2007 Annual Academic Conference of China Society of Natural Resources Held in Xi＇an

The 2007 Annual Academic Conference of China Society of Natural Resources （CSNR） was held on July 28-30 in Xi＇an, Shaanxi Province of Northwest China. This conference was co-sponsored by CSNR and Shaanxi Normal University, and also supported by the Institute of Geographic Sciences and Natural Resources Research. A total of more than 500 scholars from over 140 universities, institutions and the government departments concerned in mainland China participated in this conference.[第一段]     

Investigating the geomorphic characteristics of an Amazonian headwater stream draining a páramo ecosystem

Páramos are neotropical alpine grasslands located in the northern Andes of South America. Although they cover important headwater regions, little is known about the hydro-geomorphic characteristics of páramo river systems, which are increasingly being impacted by human use and climate change. The objective of this research is to characterize the geomorphology of the Ningar River, Ecuador, an Amazonian headwater river that drains a 22.7 km2 páramo sub-basin, by (1) classifying the geomorphology based on common geomorphic classifications, (2) deriving downstream hydraulic geometry relationships, and (3) performing a global comparison with mountain river systems. Common geomorphic field surveying techniques were used to acquire the necessary data. Results suggest that the Ningar River has similar form-function characteristics as other known mountain headwater streams and corresponds to commonly known stream classification systems, but displays more of an alluvial character than might be expected for montane headwater streams as a result of a convexity in the stream’s longitudinal profile. Additionally, preliminary analyses suggest that other páramo headwater streams may exhibit similar characteristics; thus, the findings of this research are important for future management and protection of these valuable headwater ecosystems.     

Why are glacial lakes in the eastern Tianshan Mountains expanding at an accelerated rate?

Monitoring alpine lakes is important for understanding the regional environmental changes caused by global warming. In this study, we provided a detailed analysis of alpine lake changes in the Tianshan Mountains (TS) and discussed their driving forces based on Landsat TM/ETM+/OLI, WorldView-2, Bing, Google Earth, and ASTER imagery, along with climatic data from 1990 to 2015. The results showed that during the study period, the total number and area of alpine lakes in the eastern TS exhibited an increasing trend, by 64.06% and 47.92%, respectively. Furthermore, the continuous expansion of glacial lakes contributed 95.12% and 94.17% to the total increase in the number and area, respectively, of alpine lakes. Non-glacial lakes exhibited only intermittent expansion. Since the 1990s, the new glacial lakes in the eastern TS have been mainly proglacial and extraglacial lakes. Over the past 25 years, eastern TS has experienced a temperature increase rate of 0.47 °C/10a, which is higher than that in other TS regions. The rapidly warming climate and glacier recession are the primary causes of the accelerated expansion of glacial lakes in the eastern TS.     

The end of an affair? Geography and fertility in late post‐transitional societies

A common theme in the writings of population geographers with a fertility interest has been a concern with the convergence of interregional fertility differentials. It is now clear, however, that the widespread achievement in western societies of below‐replacement fertility has resulted in a dramatic diminution of most forms of differential fertility, whether sectoral or spatial. The question of ‘what remains for the spatial analyst working in the traditional ecological mode?’ must therefore be posed. An analysis of small‐area fertility differentials in NSW in 1986 suggests (a) that most of the variability in local marital and total fertility is not statistically significant, and (b) that even if this problem is ignored, traditional ecological analysis has only trivial ‘explanatory’ power. While complete spatial uniformity is unlikely ever to be achieved, it is argued that the intrasocietal convergence of reproductive norms and behaviour has proceeded so far that conventional geographic approaches to the analysis of fertility are unlikely any longer to be — if they ever were — fruitful.