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This article considers the history of a particular Latvian cultural landscape, located on the coast of the Baltic Sea. Known as an aizjomi landscape, it consists of small, humanly made tilths on the seashore. These features are both physical elements and repositories of historical and cultural meaning. In one sense, through hard labor humans created the aizjomi landscape, adjusting the morphological and dynamic elements of the landscape and continually maintaining them. These human efforts made agriculture possible in the dunes, and in so doing they fashioned a means for producing a livelihood and, indeed, for sustaining life. The aizjomi landscape became a materialization of the people's day‐to‐day life in the middle and late nineteenth century and can thus be considered a “taskscape,” pulsating simultaneously with the rhythm of nature and historical events. I have analyzed empirical evidence from archival documents, reviewed ecological and historical studies, and conducted field research on specific farming practices that shaped the landscape that, in turn, shaped agricultural activities. Through a retrospective analysis I trace the development and decline of the aizjomi landscape.  相似文献   
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Beach sands located above the sea water level exist in an unsaturated, rather than a fully saturated or dry state. Within the unsaturated zone, a steep excavated surface can be sustained for some unknown but finite time, and some slopes may remain stable for extended time periods due to capillary forces. These observations clearly indicate small but nonzero values for attraction strength (tensile strength and cohesion) in unsaturated beach sands, especially apparent but not confined to settings where there are low stress levels. Thus, experiments were carried out to quantify the magnitude of attraction strength in moist sands (D r ?=?30%) and to examine the variation of these values as a function of moisture content and presence of a small amount of fines. Tensile strength, which is significantly different from zero, increases with increasing moisture content and fines. However, the influences of fines on the tensile strength are substantially dependent on the water content. Apparent cohesion strength is also identified in moist sands. A simple relationship between tensile strength and apparent cohesion is proposed using the obtained data. This study would help to further understand the phenomenon of stability of beach sands.  相似文献   
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