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We analyzed the nutritional status of urban and rural schoolchildren from Mendoza (Argentina), but avoided rural and urban categorization by generating subpopulations as a function of their socioenvironmental characteristics. We transformed weight and height data into z-scores using the CDC/NCHS growth charts; defined underweight, stunting, and wasting by z-scores of less than -2 SD; and calculated overweight and obesity, according to the cutoff proposed by the International Obesity Task Force. Socioenvironmental characteristics included housing, public services, parental resources, and farming practices; we processed these variables by categorical principal-component analysis. The two first axes defined four subgroups of schoolchildren: three of these were associated with urban characteristics, while the remaining subgroup was considered rural. Nutritional status differed across groups, whereas overweight was similar among the groups and obesity higher in urban middle-income children. Urban differences were manifested mainly as underweight, but rural children exhibited the greatest stunting and wasting. Thus, the negative effects of environment on nutritional status in children are not restricted to poor periurban and rural areas, though these are indeed unfavorable environments for growth: some urban families provide children with sufficient quantity and diversity of foods to expose them to obesity. By contrast, the more affluent urban families would appear to have greater possibilities for allowing their children to adopt a healthy life-style. Although the causes of differences in nutritional status between middle- and high-income urban groups are not clear, these determinants probably involve economic as well as educational influences.

The cities studied are in different stages of nutritional transition. Puerto Madryn is undergoing growing industrialization and urbanization and thus exhibits characteristics typical of an 'obesogenic' environment. General Alvear, a less complex urban centre, where some cultural patterns related to an agrarian way of life appear to have been retained, is situated at a less advanced stage.

An analysis of the evolution of sedimentation rates and disasters caused by surface geologic processes during the last century, at a global scale, is presented. Results show that erosion/sedimentation processes and frequency of such disasters increased substantially, especially after midtwentieth century, coinciding with the period of intense change known as the "Great Acceleration." Increases for this type of disasters are significantly greater than for other disasters related to natural processes, and about 1 order of magnitude in little more than half a century. This implies an important "global geomorphic change." Comparisons and correlations between changes observed in those processes and potential natural (rainfall) and human (degree of land surface transformation) drivers showed a strong relationship with the latter, and not so clear with the former. This suggests that the intensification of surface geologic processes is most likely due to a greater extent to a land transformation/geomorphic processes coupling than a climate/geomorphic processes one.Plain Language Summary It is usually assumed that geologic processes change extremely slowly, and this is in general the case when considered within a human time frame. However, geologic activity affecting land surface appears to be changing very rapidly. Data gathered in very different parts of the world show that since the end of the nineteenth century, very especially after midtwentieth century, sediment is accumulating more and more rapidly in very different sedimentation environments. This indicates that erosion (and soil loss) is becoming more intense in all sorts of environments and under very varied climate conditions. Also, the frequency of disasters caused by floods and landslides is increasing in a similar manner. Over tenfold increases seem to have taken place in less than a century. Of course, population growth implies greater exposure and therefore higher probability of disasters, but the magnitude of the increase observed can hardly be explained by this. Results point to an intensification of processes due to the interaction between water and land surface (geomorphic processes), as well as related (not so "natural") hazards. It appears to be one of characteristics of the so called Anthropocene (the age of humans). An analysis of the variations experienced by rainfall and by indicators of the intensity of human activities suggests that this expression of global change (global geomorphic change) is very likely caused mainly by land surface modification, rather than by climate change. If this were confirmed, it would have important implications. It would probably be better to focus mitigation of both undesirable effects not only on climate change (surely necessary) but mainly on land use management and practices. Whereas results on the former require international, global action, in the latter case results could be obtained through national or local policies.

The distribution of weight and height of schoolchildren, coming from most regions of the country, differs from those of national and international references. It should be advisable to establish a new national reference based on internationally recognized methodological criteria that adequately reflect the biological and cultural diversity of the Argentinean populations.

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The nature and amount of sediments in various lakes, intermittent swampy areas and river sectors in the humid Pampa (Buenos Aires Province, Argentina) were analysed. The aim was to determine whether recent sediments in such environments could serve as an alternative resource to the brick industry, for minimising the current, high environmental impact of soil mining. Sediment sequences were obtained, and the thicknesses of the upper sediment layers, corresponding to the suballuvial (approx. 1400-700 years BP) and alluvial (approx. 250 years BP to present) were determined. Sediment samples were collected and analysed for grain size and Atterberg limits. Suitable sediments were then selected to determine the optimal brick materials and their technical properties. Similarly, control bricks were prepared with ceramic pastes of local industries. The results show that the quality of the former is similar or superior to that of the latter. The initial estimates of the available resource indicate a long-term supply for the industry. Estimates of the current sedimentation rates indicate that resource renewal might occur at a rate comparable to current consumption. The sedimentation rates have increased significantly in the past two centuriesmore so in the past few decades (the Anthropocene?)with increasing human modification of geomorphic processes. If the results presented here are confirmed, a highly sustainable model can be implemented in the brick industry.