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Striking 20-year grasshopper declines tied to quality of prairie grasses（图）
20-year grasshopper declines tied quality prairie grasses
2020/3/13
A new study shows that grasshopper numbers have declined more than 30% in a Kansas grassland preserve over the past two decades. The results were published in the journal Proceedings of the Natio...
Modifying the elastomechanics of the stem and the crown needle mass distribution to affect the diameter increment distribution: A field experiment on 20-year old Abies grandis trees
Abies grandis elastomechanics field experiment stress strain diameter increment distribution
2015/2/2
In the spring of 2000, field experiments were begun on three 20-year old grand fir (Abies grandis) to influence the elasto-mechanical behavior of the stem, as well as the distribution of the assimilat...
Variation in Growth of 20-Year-Old Provenance Trial of Sitka spruce（Picea sitchensis（Bong.）Carr.）in Great Britain
Sitka Spruce Site-Seed Origin-Provenance Growth Rate-Tree Volume-Tree Diameter at Breast Height
2009/1/14
Variation in growth of the cambial age (tree diameter) and tree volume was investigated in eight seed origins of Sitka spruce Picea sitchensis (Bong.) Carr.) grown at two sites in Great Britain. The ...