RESUMO
Pinus massoniana is a typical pioneer afforestation tree species widely distributed in southern China. It is crucial to study the ecological resilience of P. massoniana to disturbances under global warming, drying, and frequent pest infestation, which can shed lights on forest mana-gements. In this study, tree-ring samples collected from old-growth P. massoniana trees in Baisong Village, Xianyou County, Fujian Province, were used to develop the first standard chronology of P. massoniana ring width (1865-2014) in this region. The results showed that the low relative humidity from July to September and the extremely high temperature from May to September were the main limiting factors for tree growth. The extremely narrow years were identified in 1869, 1889, 1986, 1991 and 1993. These extremely narrow years were exacerbated after the persistently low values of the previously two years via the superposed epoch analysis (SEA). The insect infestations were more likely to happen in dry years. Insect outbreak exerted strongest effect on tree growth in 1889. The narrow tree-rings in 1986 and 1991 were affected by both insect infestation and drought. The other extremely narrow years were mainly affected by drought. The resistance of trees to insect infestation was weaker than that to drought event. The relative resilience of trees to insect infestation was higher than that to drought event, except for 1991. The relative resilience was the highest in 1889 and the lowest in 1991 under the influence of successive extreme events. Under the enhanced drying trend since 2000, more trees had died possibly due to the combined effects of insect infestation and drought.
Assuntos
Pinus , Árvores , Animais , China , Mudança Climática , Secas , InsetosRESUMO
We determined the complete mitochondrial genome (mitogenome) sequence of Sarcocheilichthys nigripinnis by using long polymerase chain reaction method. The total length of S. nigripinnis mitogenome is 16,680 bp, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs, and a noncoding control region. The overall base composition of S. nigripinnis is 26.36% for T, 26.67% for C, 30.07% for A, and 16.90% for G, with a slight AT bias of 56.43%.