The heavy metal pollution caused by road run-off water constitutes a problem in urban areas. The metallic load associated with road sediment must be determined in order to study its impact in drainage systems and receiving waters, and to perfect the design of prevention systems. This paper presents data regarding the sediment collected on road surfaces in the city of Torrelavega (northern Spain) during a period of 65 days (132 samples). Two sample types were collected: vacuum-dried samples and those swept up following vacuuming. The sediment loading (g m(-2)), particle size distribution (63-2800 microm) and heavy metal concentrations were determined. The data showed that the concentration of heavy metals tends to increase with the reduction in the particle diameter (exponential tendency). The concentrations ofPb, Zn, Cu, Cr, Ni, Cd, Fe, Mn and Co in the size fraction <63 microm were 350, 630, 124, 57, 56, 38, 3231, 374 and 51 mg kg(-1), respectively (average traffic density: 3800 vehicles day(-1)). By increasing the residence time of the sediment, the concentration increases, whereas the ratio of the concentration between the different size fractions decreases. The concentration across the road diminishes when the distance between the roadway and the sampling siteincreases; when the distance increases, the ratio between size fractions for heavy metal concentrations increases. Finally, the main sources of heavy metals are the particles detached by braking (brake pads) and tyre wear (rubber), and are associated with particle sizes <125 microm.

The study of the behavior of deposited sediments on an urban surface serves to determine its characteristics of build-up, in dry periods, and of wash-off, during a rain event. Thus, these can be used later to indicate the presence of pollutants in an area. This paper presents data regarding the sediment collected on a road surface in the city of Torrelavega in northern Spain during a period of 65 days during which 132 samples were collected. The rainfall during the sampling period corresponded to 29% of the total rainfall registered in the same year. Two types of sediment collection samples were obtained: vacuumed dry samples (free load) and those swept up following vacuuming (fixed load). For each type of collected sample, the sediment loading, particle size distribution in seven fractions and moisture were determined. The data showed that the sediment loading (g m(-2)) and vacuumed availability of the load that was more strongly adhered to the surface, "fixed load", increases with the number of dry days. The particle size distribution of the collected sediment tended to be finer with the increase in number of dry days. Particle sizes less than 125 microm presented the greater rate of accumulation in dry weather and those less than 500 microm, the greater susceptibility to being washed off during a storm event.

In this regard, the tools identified are mainly used in the perception studies in farming communities (65.4%) before than in indigenous communities (34.6%). Furthermore, it was identified the following important perceptions: (i) climate variability (94.1%), (ii) temperature increase (91.2%), (iii) changes in precipitation (85.3%), and (iv) change in cultural habits (55.9%). Results suggest that the dominant perception is that there is a change was mainly due to the climatic factor; above, represented by 90.2% of the documents identified. Finally, the strategies for adaptation to climate change in Latin American local communities can be grouped into three categories: (i) agriculture (57.6%), (ii) community (48.1%), and (iii) water (40.4%).

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