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Despite the dramatic changes in land-use arising from expansion of the palm oil industry, soil biodiversity in oil palm plantations has been little investigated. The present study aims to assess the effect of organic waste recycling (empty fruit bunches, EFB) on soil biodiversity in a mature plantation in Sumatra, Indonesia. A chronosequence was delineated taking into account the time between the applications of EFB and soil sampling; intervals of 1, 3, 6, 12, 18 and 24 months were compared with control plots without EFB application. Soil physical and chemical characteristics and macrofauna and nematofauna populations were analysed. The findings highlighted three distinct periods: a first disturbance period (0-6 months) showing a marked increase in pH, potassium content, base saturation and macrofauna abundance, especially ants, whereas earthworm, millipede and nematode populations were substantially reduced; a resilience period (6-18 months); and a final period (18-24 months) showing an improvement in most soil fertility parameters and a high density of earthworms, millipedes and nematodes. The impact of EFB application on soil quality changed as a function of time, and the present results explain the apparent discrepancy of some previous published results. This research is the first stage towards developing new strategies for enhancing soil biodiversity and related services for sustainable oil palm cultivation. Additional keywords: Elaeis guineensis, empty fruit bunches, fertilisation practices, soil macrofauna, soil nematofauna., Introduction Oil palms have been planted on 16Mha globally, mostly in Indonesia and Malaysia, representing dramatic changes in land-use. Oil palm cultivation--given the combination of societal, agricultural and environmental issues [...]

A simple two-neuron model of a discrete Hopfield neural network is considered. The local stability is analyzed with the associated characteristic model. In order to study the dynamic behavior, the Fold bifurcation is examined. In the case of two neurons, one necessary condition for yielding the Fold bifurcation is found. In addition, the stability and direction of the fold bifurcation are determined by applying the normal form theory and the center manifold theorem. [ABSTRACT FROM AUTHOR]

Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.

Assessing how much management of agricultural landscapes, in addition to protected areas, can offset biodiversity erosion in the tropics is a central issue for conservation that still requires cross-taxonomic and landscape-scale studies. We measured the effects of Amazonia deforestation and subsequent land-use intensification in 6 agricultural areas (landscape scale), where we sampled plants and 4 animal groups (birds, earthworms, fruit flies, and moths). We assessed land-use intensification with a synthetic index based on landscape metrics (total area and relative percentages of land uses, edge density, mean patch density and diversity, and fractal structures at 5 dates from 1990 to 2007). Species richness decreased consistently as agricultural intensification increased despite slight differences in the responses of sampled groups. Globally, in moderately deforested landscapes species richness was relatively stable, and there was a clear threshold in biodiversity loss midway along the intensification gradient, mainly linked to a drop in forest cover and quality. Our results suggest anthropogenic landscapes with high-quality forest covering >40 % of the surface area may prevent biodiversity loss in Amazonia., (© 2018 Society for Conservation Biology.)