How does mining affect the environment?

The major impact of mining on the environment is mainly due to the physical damage of the landscape and the production of large volume of harmful wastes. In general, only a small fraction of the ore is valuable, the remaining large part is waste (tailings). For example, in the Cu mining industry, only about a kilogram of the metal is extracted from one-half ton rock. (Ore is an economic term for a rock from which a mineral can be extracted profitably).

The figure above summarizes the environmental impact of mining and smelting. It shows that mining and smelting produce solid, liquid and gaseous wastes/contaminants. These cause serious environmental damage once they are discharged to the land (terrestrial ecosystem) and bodies of water (aquatic ecosystems) or when they are emitted into ambient air. In particular, they cause soil and water acidification, air, water, soil and plant contamination by trace elements, deterioration of soil biology and fertility, and soil erosion.

Studies have shown that trace metals remain in the soil for a long time ranging from hundreds to thousands of years. Cd, Ni, and Zn have a relatively shorter residence time in the soil than Pb and Cr which may remain for several thousand years. This simply means that it is not easy and cheap to rehabilitate an abandoned mining site. In fact, the physical destruction of the landscape can be irreparable. And more importantly, the health risk of the contaminants that have already entered the food chain can remain for a long time.

Photo: Manicani island, Eastern Samar. Source: www.nickelore.blogspot.com (Feb 2, 2012)

References

Skinner B.J., S.C. Porter, and J. Park. 2004. Dynamic Earth. An introduction to Physical Geology. John Wiley and Sons, NJ.

Dudka S. And D.C. Adriano. 1997. Environmental impacts of metal ore mining and processing: a review. Journal of Envi. Quality 26: 590-602.

A green soil in the highlands of Samar

A soil at the heart of Samar, the third largest island of the Philippine archipelago, and along the Paranas-Taft road at about 300 m above sea level (within the Samar Island Natural Park) easily catches the attention of travelers. This is because it is unique: it is green in color. As far as I know, no soil with such color has yet been reported in the scientific literature.

The dominant green color is probably due to the abundance of the secondary mineral called melanterite, a hydrated iron sulphate mineral (FeSO4.7H2O) formed from the decomposition of pyrite or other iron minerals due to the action of surface waters. It is commonly found in mines as a post-mining formation on mine walls, in sulfidic sedimentary and metamorphic rocks as well as in coal and lignite deposits. It indicates the possible presence of sulfuric acid and should not be handled with bare hands or inhaled (www.mindat.org).

The green soil developed from mudstone interlayered with coal deposit. The site is not far from an area which was mined for coal and pyrite and thus appears to satisfy the environmental conditions favorable for melanterite occurrence.

We had the chance to examine the soil during our fieldwork in Samar on 2-3 Feb 2012 as part of my graduate course in pedology (Soil Science 212). We plan to conduct a detailed pedological and geochemical study on this soil in the near future. For easy reference, I suggest to call it “Samar melanterite soil”.

(Members of the team: Ariel Bolledo, Mark Moreno, Pearl Carnice, Richel Lupos, Dr. Ian Navarrete (Humboldt Research Fellow), Forester Elpidio Cabahit Jr. from the Samar Island Natural Park, and myself)

The origin of the catena concept

The catena concept in soil science comes from the Latin word “catena” which means chain. So it is a chain of soils linked by topography. It also refers to a sequence of soils in different positions in the landscape. It was introduced to the scientific literature by Geoffrey Milne (1898-1942) in a paper entitled “Some suggested units of classification and mapping particularly for East African soils” published in Soil Research-Bodenkundliche Forschung, Supplement to the Proceedings of the International Union of Soil Science Vol. IV No. 3 (1935), pp: 183-198. He noted “the regular repetition of a certain sequence of soil profiles in association with topography” in East Africa which was also observed earlier (in 1911 and 1912) by the German Peter Vageler. Milne wrote that a distinctive word is needed in referring to this phenomenon hence, he proposed the word catena.

Ernst Schlichting (1923-1988) who was professor at the University of Hohenheim in Stuttgart pioneered the approach of considering the soil always as part of the landscape. He proposed that soils in different positions in the catena exchange materials through transport processes and thus could be compared to the transfer processes between horizons in a soil profile. In Schlichting’s view, the genesis of a soil can only be understood if its relation to the other soils in the catena is taken into consideration.

Catena is now also widely used in other sciences particularly ecology albeit with a slightly different meaning (e.g. a catena of terrestrial ecosystems).

(The upper figure shows the linkages between soils in a catena according to Sommer and Schlichting 1997, Geoderma 76: 1-33. The lower figure shows the typical catena in the highlands of Leyte, Philippines).

Hohenheimer Bodenkundliche Hefte: 20 years of publishing original soil research

The Hohenheimer Bodenkundliche Hefte (ISSN 0942-0754) or Hohenheim Soil Science Book Series will be 20 years old in 2012. Since the release in 1992 of Volume 1 with the title “Stickstoff-Dynamik in Catenen einer erosionsgepraegten Loesslandschaft by G. Lorenz” (Nitrogen dynamics in catenas of an erosion-affected loess landscape), it has already published a hundred volumes of original and relevant soil research. Volume 100 which came out last year (2011), was authored by Shabnam Rathore and carried the title “Assessment of biomass production potential on salt affected land: a soil and terrain database case study (SASOTER) in Badin District, South of Pakistan.”

Published by the renowned Institute of Soil Science and Land Evaluation of the University of Hohenheim in Stuttgart, Germany, this book series publishes dissertations and habilitations carried out at the Institute. During its early years, it was edited by Prof. U. Babel (Soil Biology), Prof. W.R. Fischer (Soil Chemistry), Prof. K. Roth (Soil Physics), and Prof. K. Stahr (Soil Science and Petrography). The present editors are Prof. E Kandeler (Soil Biology), Prof. Y. Kuzyakov (Soil Biogeochemistry), Prof. K. Stahr (Soil Science and Petrography) and Prof. T. Streck (Soil biogeophysics), all internationally well-known soil scientists and authors at the Institute.

In its 20 years of existence, the Hohenheimer Bodenkundliche Hefte has clearly established itself as an important publication in soil science. As can be seen from Google Scholar, many of the titles published in the book series have been cited by papers in various prestigious international journals and books. Vol. 36 on dust deposition of soils in West Africa by Dr. Ludger Herrmann has been the most frequently cited volume of the book series.

World Soil Day

December 05 of every year is celebrated as World Soil Day by the global community of more than 60,000 soil scientists. According to the official IUSS website, World Soil Day is held on the said date since it is the birthday of H.M. King Bhumibol Adulyadej, The King of Thailand, who has officially sanctioned the event.

As a tribute to the soil as a vital resource, I am posting below a poem written in 2007 by one of my former students at Visayas State University, Juvia P. Sueta. Juvy is now finishing her PhD at the Buesgen Institute, University of Goettingen, Germany.

The Soil Beneath

by Juvia P. Sueta

The soil tells a

fascinating story

of enduring patience

and great beauty.

Out of the hardened rock,

it changes into

an interesting mass

of sand, silt, and clay.

Exposed to the rain, wind

and sunshine, it

grows to maturity.

Time polished it,

throughout all history.

Out of its bosom,

the flowers bloom

and trees grow steadily.

And in its face,

the children play.

Below it;

scholars, artists,

beggars, and poets lay.

Great is the earth,

it cares and nourishes

the whole humanity.

It is nature’s best habitat,

sustaining creatures,

strong or tiny.

It bears witness,

to all that took place

throughout the ages.

It holds the secrets

of past or future events.

it is a treasure chest,

keeping nature’s wealth.

And so nothing compares

to the soil beneath.

The impacts of mining in the Philippines

Mining is a top and very controversial environmental issue in the Philippines today. It is increasingly becoming a divisive issue too. The government cite economic benefits as sufficient justification to support and encourage mining. In fact, the Intellasia News Online (http://www.intellasia.net) reported on 08 August 2011 that the Philippines' Mines and Geosciences Bureau (MGB) has announced that about 5 million hectares of potentially mineralised areas across the archipelago are now open to local and foreign investors. On the other hand, environmental and religious groups strongly oppose mining because of its well-known negative environmental and health impacts.

A Fact-Finding Team composed of human rights and environmental experts from the United Kingdom which looked into the impact of mining on the environment and peoples' livelihoods in the Philippines highlighted the occurrence of mining-related human rights abuses affecting local communities especially indigenous people; extrajudicial killings of persons protesting against mining; corruption in the mining sector; political pressure on the judiciary resulting in pro-mining decisions; and environmental impacts.

The team observed that "the record of mining companies with regard to environmental protection, disasters and post-mining clean-up in the Philippines is widely acknowledged, even with the government, to be very poor. As of 2003, there had been at least 16 serious tailing dam failures in the preceding 20 years and about 800 abandoned mine sites have not been cleaned up. Clean-up costs are estimated in billions of dollars and damage will never be fully reversed."

It warned that "water contamination from mining poses one of the top three ecological security threats in the world. Many mining applications in the Philippines are in water catchment areas close to the sea, and pose major threat to valuable marine resources." The severe pollution of the Taft river system in Eastern Samar as a result of the mining activities in Bagacay is a vivid example (please see related article in this blog).

The report also emphasized the very high geo-hazard risks in the Philippines. "In the Philippines, over half of the active mining concessions and two-thirds of exploratory concessions are located in areas of high seismic risk where earthquakes are likely."

"The Philippines is considered as the hottest hotspot in the world in terms of threats to its mega diverse biodiversity. Thus there is an urgent need to properly manage its natural resources. It is estimated that 37% of Philippine forests may be exposed to new mining."

Should universities campaign for or against mining?

Some leading state universities in the Philippines are reportedly being pressured by environmental and religious groups to take an “official” anti-mining stand. Universities may take lead in promoting responsible mining and in fact should conduct relevant scientific investigations to prevent or minimize the impacts of mining on the environment and people. But universities should not take an anti or a pro mining stand. They should remain neutral and allow their constituents (the researchers and scientists) to evaluate facts and decide for themselves what stand to take about mining. A university should strive to seek the truth. Always.

Reference:

Doyle C, Wicks C, and Nally F. 2007. Mining in the Philippines: Concerns and Conflicts. Report of a Fact-Finding mission to the Philippines. Society of St. Columban, West Midlands, UK, 63pp.

Jackfruit is suitable for Leyte and Samar islands

Jackfruit (Artocarpus heterophyllus) is now an important crop in Leyte and Samar islands or Eastern Visayas (Region 8) in the Philippines. In fact, the Department of Agriculture (Region 8) and the Visayas Consortium for Agriculture and Resources Program (ViCARP) based at VSU have made it a priority crop for the region. Consequently, more studies are now being conducted by research centers and universities to improve jackfruit productivity and to develop jackfruit-based food products.

A research funded by the Bureau of Agricultural Research (Manila) from 2000 to 2003 titled "Characterizing biophysical environments for research prioritization and agricultural production in Region 8 (VB Asio, BB Dargantes, PP Garcia, K Israel)" produced the first solid scientific evidence that jackfruit is generally suitable for the region based on climate, geology, topography, land use, and soil factors. Among the significant outputs of this research were the suitability maps developed using GIS for jackfruit, rambutan, mango, abaca, coconut, sweetpotato and cassava which were distributed to all government agencies in the region starting 2004.

The suitability maps and other highlights of the research were also presented during the First Regional Fruit Congress in Tacloban City in 2003 which was attended by researchers, agricultural technicians, farmers, and policymakers. It was agreed at this congress to give priority to jackfruit and not mango which was found generally unsuitable for most parts of the region (except the northwestern side of Leyte whose climatic, geologic and soil characteristics are closely similar to those of the nearby Cebu island).

(The land suitability map for jackfruit shown was the first draft version we developed in 2002. Photo of jackfruit tree was taken from www.backpackingmalaysia.com)

Reference:

Asio VB, BB Dargantes, PP Garcia and K Israel. 2004. Characterizing biophysical environments for research prioritization and agricultural production in Region 8 (Leyte-Samar). Terminal Report, LSU-DA-BAR GIS Project.