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1.
Himalayan cedar (Cedrus deodara (D. Don) G. Don) due to its long age and wide ecological amplitude in the Himalayan region has strong dendroclimatic potential.
A well replicated ring-width chronology of it, derived from the ensemble of tree-ring samples of two adjacent homogeneous
sites, has been used to reconstruct precipitation for the non-monsoon months (previous year October to concurrent May) back
to AD 1171. This provides the first record of hydrological conditions for the western Himalayan region, India during the whole
of the ‘Little Ice Age’ and latter part of the ‘Medieval Warm Period’. The reconstruction revealed the wettest and the driest
non-monsoon months during the fourteenth and the thirteenth centuries, respectively. The seventeenth century consistently
recorded dry non-monsoon months in the western Himalayan region. Surplus precipitation, especially more pronounced since the
1950s, is recorded in the current century. 相似文献
2.
The fossil remains of 43 bowhead whales were mapped on the raised beaches of western Wollaston Peninsula, Victoria Island, Canadian Arctic, near the historic summer range limit of the Bering Sea stock in the Beaufort Sea. The elevations and radiocarbon ages of the remains demonstrate that the bowhead ranged commonly into the region following the submergence of Bering Strait at ca. 10,000 14C yr B.P. until ca. 8500 14C yr B.P. During the same interval, bowheads ranged widely from the Beaufort Sea to Baffin Bay. Subsequently, no whales reached Wollaston Peninsula until ca. 1500 14C yr B.P. Late Holocene populations evidently were small, or occupations were brief, in comparison to those of the early Holocene. Although the late Holocene recurrence may relate to the expansion of pioneering Thule whalers eastward from Alaska, there are few Thule sites and limited evidence of Thule whaling in the area surveyed to support this suggestion. 相似文献