Water and Population in the Yucatan Peninsula

This paper explores the relation between population and water in the Yucatan Peninsula of southeastern Mexico, and how issues related to water have affected the inhabitants of the region from the time of the ancient Maya to today. The paper also discusses how water issues will affect the future population of the region. Water has historically been a scarce resource in the Yucatan. Despite a relatively humid climate, a combination of geologic and geographic conditions limit the availability of water in the region. The inhabitants of the region, from the ancient Maya to the present day population, have devised different strategies for coping with that scarcity. In recent years, however, the population of the Yucatan has grown rapidly as a result of economic development, especially the expansion of the tourism sector. With that rapid growth have come increased problems with both water supply and wastewater disposal. These problems are likely to be further magnified in the future as the population of the region continues to expand. This paper discusses future water needs of the Yucatan and different possibilities for meeting those needs. The paper also includes an annotated bibliography which provides some short notes about some of the most useful references cited and where they can be easily located

Pest, jøder og samfundsorden - forgiftningsrygter og jødeforfølgelser i forbindelse med den Sorte Død

Den Sorte Død var den største epidemikatastrofe, der ramte Europa i det 2. årtusind e.Kr. Fra 1347 til 1353 bortrev den måske 40-50 % af kontinentets befolkning. En af samtidens forklaringer var, at pesten skyldtes onde mennesker, som forgiftede drikkevandet. I det Tyske Rige blev dette rygte knyttet til jøderne. Efter at deres skyld var "bevist" ved processer i Dauphiné og Savoyen i 1348, medførte rygtet massivt pres fra befolkningen på myndighederne for at få jøderne udryddet.I artiklen gennemgås eksempler på begivenhedsforløbet i de jødeforfølgelser, som fandt sted i det Tyske Rige i 1348-1349, ligesom pavens tvetydige holdning bliver analyseret. Stillet over for et aggressivt folkekrav havde magthaverne valget mellem at beskytte jøderne og derved risikere at miste deres legitimitet eller at bevare skinnet af deres autoritet ved at ombringe jøderne. Kun de stærkest funderede fyrster og bystyrer var i stand til at fastholde den første løsning

Fractionation of iron species and iron isotopes in the Baltic Sea euphotic zone

To indentify sources and transport mechanisms of iron in a coastal marine environment, we conducted measurements of the physiochemical speciation of Fe in the euphotic zone at three different locations in the Baltic Sea. In addition to sampling across a salinity gradient, we conducted this study over the spring and summer season. Moving from the riverine input characterized low salinity Bothnian Sea, via the Landsort Deep near Stockholm, towards the Gotland Deep in the Baltic Proper, total Fe concentrations averaged 114, 44, and 15 nM, respectively. At all three locations, a decrease in total Fe of 80–90% from early spring to summer was observed. Particulate Fe (PFe) was the dominating phase at all stations and accounted for 75–85% of the total Fe pool on average. The Fe isotope composition (δ 56Fe) of the PFe showed constant positive values in the Bothnian Sea surface waters (+0.08 to +0.20‰). Enrichment of heavy Fe in the Bothnian Sea PFe is possibly associated to input of aggregated land derived Fe-oxyhydroxides and oxidation of dissolved Fe(II). At the Landsort Deep the isotopic fractionation of PFe changed between −0.08‰ to +0.28‰ over the sampling period. The negative values in early spring indicate transport of PFe from the oxic-anoxic boundary at ∼80 m depth. The average colloidal iron fraction (CFe) showed decreasing concentrations along the salinity gradient; Bothnian Sea 15 nM; Landsort Deep 1 nM, and Gotland Deep 0.5 nM. Field Flow Fractionation data indicate that the main colloidal carrier phase for Fe in the Baltic Sea is a carbon-rich fulvic acid associated compound, likely of riverine origin. A strong positive correlation between PFe and chl-a indicates that cycling of suspended Fe is at least partially controlled by primary production. However, this relationship may not be dominated by active uptake of Fe into phytoplankton, but instead may reflect scavenging and removal of PFe during phytoplankton sedimentation