The climate of the Holocene and its landscape and biotic impacts

Abstract

The Holocene Epoch has abundant paleoclimatic archives at relatively high temporal and spatial resolution, which have helped to reveal the patterns of natural climate variation during the present interglacial period and the impacts of that variation on landscapes and biota. This article presents a personal review of some interesting insights that have emerged from analysis of Holocene paleoclimatic records from continental archives at orbital to multidecadal scales. These include how the increased density of sites in Asia, South America and Africa have revealed unforeseen spatial patterns of variation in the dynamics of the monsoon systems at orbital scales and a better characterisation of the magnitude of multidecadal and centennial variation in various parts of the globe. Among interglacial periods, the Holocene is unique as the period in which more complex human civilisations and agriculture developed, and many recent studies have evolved our understanding of the nature of the human impact relative to natural dynamics prior to large-scale population expansion

Community Abundance of Resprouting in Woody Plants Reflects Fire Return Time, Intensity, and Type

“…The short time interval covered by the remote-sensed fire products leads to uncertainty in the estimated FRI, particularly in regions with long return times and given the highly stochastic nature of fire occurrence. Although we truncated the FRI estimates at 5000 years, it is unlikely that the higher-end estimates are realistic, given known changes in climate and vegetation over the late Holocene [54][55][56] and their impacts on fire regimes [3,57,58]. However, in the absence of better-controlled estimates of the FRI, we assume that the trend towards decreasing proportions of resprouters with increasing FRIs is realistic, even if the absolute magnitude of the estimated FRI values is not.…”

Holocene Lacustrine Environment in the Western Eritrea-evidence from Freshwater Shells

“…A number of studies have been carried out on the impact of climatic change after the mid-Holocene Epoch in the East and North African countries by examining Holocene freshwater shells. From the previous data compiled by [20], numerous paleoclimatic data show that in parts of tropical Africa precipitation increased in the early to mid-Holocene which produced the well-documented greening of the Sahara and Sahel, and large lakes of the Holocene have now disappeared in the northern Africa, where higher water levels throughout East Africa were estimated. The discovery of these shells and their 14 C age confirmed the existence of a lake in western Eritrea during the mid-Holocene epoch.…”