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Results for “Small Wars Journal”

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3 recordsLinked to original sources
USGS2014

The role of conflict minerals, artisanal mining, and informal trading networks in African intrastate and regional conflicts

The relationship between natural resources and armed conflict gained public and political attention in the 1990s, when it became evident that the mining and trading of diamonds were connected with brutal rebellions in several African nations. Easily extracted resources such as alluvial diamonds and gold have been and continue to be exploited by rebel groups to fund their activities. Artisanal and small-scale miners operating under a quasi-legal status often mine these mineral deposits. While many African countries have legalized artisanal mining and established flow chains through which production is intended to travel, informal trading networks frequently emerge in which miners seek to evade taxes and fees by selling to unauthorized buyers. These networks have the potential to become international in scope, with actors operating in multiple countries. The lack of government control over the artisanal mining sector and the prominence of informal trade networks can have severe social, political, and economic consequences. In the past, mineral extraction fuelled violent civil wars in Sierra Leone, Liberia, and Angola, and it continues to do so today in several other countries. The significant influence of the informal network that surrounds artisanal mining is therefore an important security concern that can extend across borders and have far-reaching impacts.

Small Wars Journal↗
USGS2025

Analysis of a human-mediated microbioinvasion: The global spread of the benthic foraminifer Trochammina hadai Uchio, 1962

A non-indigenous species (NIS) of benthic foraminifera was first identified in a core collected in 1993 in San Francisco Bay, California, USA, and subsequently identified as Trochammina hadai Uchio, 1962. Archived samples and literature reviews were used to determine that the species, which is native to Asia, arrived in San Francisco Bay between the early 1960s and 1983. Through molecular analyses of specimens, archived samples and literature reviews from 1930–1983, and site surveys of harbors and estuaries along the western North American seaboard in 1994–2024, in total more than 2500 samples, we documented the presence of T. hadai at 73 locations in the USA and four in Canada. Trochammina hadai has also been recovered at nine sites in Sweden, two in France, three in Brazil, and two locations at one site in Australia. The rapid temporal and geographic spread of the NIS T. hadai in a non-native location is illustrated by a time series from 1930 to 2024 in San Francisco Bay. Between 1980 and 1986, the species' range expanded from low abundance (1.5 %) at a single site to cover nearly the entire South Bay with > 70 % abundance at some locations. By 1995 and continuing into 2010, the species expanded its range into the central and northern portions of San Francisco Bay, commonly with abundances of > 30 % and sometimes exceeding 70 %. This expansion may predate 1995, but a lack of samples makes it difficult to be more precise. Unfortunately, two Pb-210 and Cs-137-dated cores (BC01 and BC02) recovered from northern South Bay and Central Bay did not clarify this point, but additional cores may. Trochammina hadai is an infaunal opportunist that thrives in polluted locations. We surmise the species was introduced along the west coast of the USA in Puget Sound between 1902 and the 1920s, with cultivated oysters and oyster larvae and associated plant matter and residual sediment. This probably also happened in some areas of France, Sweden, and Brazil, where Japanese oysters were introduced in 1966, 1970, and 1975, respectively. After World War II, commercial shipping expanded dramatically and, with it, the release of ballast water and sediment in receiving ports, which introduced NIS worldwide. This primary vector of introduction occurred in large industrial harbors in several countries, sometimes followed by secondary introductions in small industrial centers and marinas by mud attached to the anchors and anchor chains of smaller boats.

Journal of Micropalaeontology↗
USGS2011

Lake sturgeon response to a spawning reef constructed in the Detroit river

Prior to the First World War, the bi-national Detroit River provided vast areas of functional fish spawning and nursery habitat. However, ongoing conflicting human uses of these waters for activities such as waste disposal, water withdrawals, shoreline development, shipping, recreation, and fishing have altered many of the chemical, physical, and biological processes of the Detroit River. Of particular interest and concern to resource managers and stakeholders is the significant loss and impairment of fish spawning and nursery habitat that led to the decline in abundance of most fish species using this ecosystem. Lake sturgeon ( Acipenser fulvescens ) populations for example, were nearly extirpated by the middle of the 20th century, leaving only a small fraction of their former population. Fisheries managers recognized that the loss of suitable fish spawning habitat is a limiting factor in lake sturgeon population rehabilitation in the Detroit River. In efforts to remediate this beneficial water use impairment, a reef consisting of a mixture of natural rock and limestone was constructed at the upstream end of Fighting Island in 2008. This paper focuses on the response by lake sturgeon to the different replicates of suitable natural materials used to construct the fish spawning habitat at Fighting Island in the Detroit River. Pre-construction fisheries assessment during 2006–2008 showed that along with the presence of adult lake sturgeon, spawning conditions were favorable. However, no eggs were found in assessments conducted prior to reef construction. The 3300 m 2 Fighting Island reef was placed at the upstream end of the island in October of 2008. The construction design included 12 spawning beds of three replicates each consisting of either round rock, small or large (shot-rock) diameter limestone or a mixture thereof. An observed response by spawning lake sturgeon occurred the following year when spawning-ready adults (ripe), viable eggs, and larvae were collected during May and June 2009. Additional eggs and spawning-ready adults were found in 2010 (no larval sampling occurred in 2010) as well as collection of three age-0 juvenile lake sturgeon in bottom trawls fished downstream of the reef during July 2010. Spawning lake sturgeon showed no repeatable preference for any of the four particular substrate types but showed a high degree of preference for the island side of the channel, where faster water current velocities occurred. In 2009, overall lake sturgeon egg densities across all replicates averaged 102 m -2 and seven larvae were found in night drift-net samples. In 2010, average lake sturgeon egg density was 12 m -2 and three age-0 lake sturgeon averaging 120 mm TL were collected in bottom trawls in deepwater (∼8 m depth) downstream from the constructed reef. These results demonstrated successful reproduction by lake sturgeon on a man-made reef and suggested that additions and improvements to fish spawning habitat could enhance reproduction and early life history survival of lake sturgeon in the Detroit River.

Michigan;Ontario↗