Increases in soil water content after the mortality of non-native trees in oceanic island forest ecosystems are due to reduced water loss during dry periods

The complete chloroplast genome sequence of Casuarina equisetifolia

Casuarina equisetifolia, as windbreaks, soil erosion, and sand dune stabilization with high resistant to typhoon force winds, drought and salinization, belongs to the Casuarinaceae family. In this study, the complete chloroplast genome of C. equisetifolia was sequenced by Illumina sequencing platform and annotated by Geneious Prime. The complete chloroplast genome size is 156,128 bp in length, with a large single copy region (LSC: 86,192 bp) and a small single-copy region (SSC: 18,462 bp), which was separated by a pair of 25,737 bp inverted repeated regions (IRs). The chloroplast genome of C. equisetifolia encodes total 127 genes, including 82 protein-coding genes, 37 tRNA genes, and eight rRNA genes. The phylogenomic relationship analysis suggested that the Casuarinaceae family, which includes C. equisetifolia, was more closely related to the family of Betulaceae.

When scientists become detectives: investigating systematic tree poisoning in a protected cove

The systematic killing of trees is usually aimed at eradicating pests or alien plant species susceptible to harm existing natural ecosystems. In some cases, trees may become the subject of dispute between neighbors, which sometimes ends in tree death after months or years of dispute. In this paper, we analyze a case of clandestine tree killing and look into ways through which evidence left by delinquents can be analyzed a posteriori with state-of-the-art approaches. The investigation presented here looks at a series of old-growth trees that were supposedly poisoned inside a protected, nineteenth century grove in Switzerland. After the sudden, unexplained death of several old Black poplar (Populus nigra) trees along the main alley in fall 2015 and their subsequent removal, the dying of five additional, neighboring Sycamore maple (Acer pseudoplatanus) and English walnut (Juglans regia) trees in 2016 promptly triggered a suite of criminal investigations at the property. During an initial inspection, a large number of boreholes was found in the root plates of the dying trees. We present findings obtained from tree-ring, wood anatomical and dendrogeochemical investigations performed on root, stem and leave material from the assumedly poisoned trees and show that massive amounts of chemical elements – supposedly in the form organic pesticides with high Al, As, Fe, Cr, Ni contents, aluminum phosphides or glyphosate-based pesticides – were injected into 36 boreholes drilled into the roots around September 2016. Results obtained in this study are currently used in criminal investigations, and are a nice example of how scientific detectives can help their “real World” colleagues in identifying delinquents.

Response of Soil Moisture to Single-Rainfall Events under Three Vegetation Types in the Gully Region of the Loess Plateau

Precipitation is the main source of soil moisture recharge in the gully region of the Loess Plateau, and soil moisture is the main and most important water resource for vegetation activities in semiarid regions. To identify the contributions to soil moisture replenishment from rainfall of different intensities, this study conducted a soil moisture monitoring experiment involving continuous measurements at 30-min intervals in areas of Robinia pseudoacacia artificial forestland, Pinus tabulaeformis artificial forestland, and grassland from 1 March to 31 November 2017. The results indicated that there was a positive relationship between the infiltration coefficient and precipitation until the relationship obtained a stable value. When the precipitation was greater than 30 mm, soil moisture was replenished up to the 150 cm soil layer in grassland, and when the precipitation was greater than 40 mm, soil moisture was replenished up to the 150 cm soil layer in P. tabulaeformis artificial forestland. However, only precipitation greater than 50 mm replenished the soil moisture at the 150 cm soil layer in R. pseudoacacia artificial forestland. These three vegetation communities play important roles in soil and water conservation during ecological restoration. The results of this study can guide vegetation configurations in vegetation recovery and reconstruction efforts in the gully region of the Loess Plateau.