INTRODUCTION Bushes and trees with deep roots in the soil are affected from the heavy metal accumulation in the soil 1 . Tissues of plants that grow in this soil with high heavy metal concen- tration contain high ratios of those heavy metals. Heavy metal concentration in plants is used in biogeochemical studies 2-4 . This plant is termed as indicator plant and can be used as environmental monitor in mine prospection 5 . Indicator plants are living organisms that provide information about the quality of the environment they grow in. A biogeochemical study can provide geochemical data on other surface materials, which are not found in substrate. Composition of plants reflects presence of an element near root system, plants’ ability of absorption, delivery and accu- mulation of elements. The procedure in biogeochemical analyses provides dynamic nature of living plant that cause a variation in plant chemistry. In biogeochemical studies, indi- cator plants, particularly which collect some elements at high ratios, correspond to the concentrations of these elements in substrate 2,3,6-10 . Soil contaminated by these metals due to erosion and operation of ore level creates a direct health problem for the animals and humans living in that region. The animals that feed on the plants growing in these soils can store these Environmental Impact Assessment of Mining Activities in the Vicinity of Madenköy (Nigde) Using Biogeochemical Modeling TULIN GEDIK 1 and MUSTAFA AKYILDIZ 2,* 1 Mineral Research & Exploration General Directorate Department of Geology, Ankara 06800, Turkey 2 Department of Geological Engineering, Faculty of Engineering & Architecture, Çukurova University, Adana 01330, Turkey *Corresponding author: Fax: +90 322 3386715; Tel: +90 322 3387131; E-mail: akyildizm@cu.edu.tr; akyildizmst@gmail.com (Received: 2 April 2013; Accepted: 25 September 2013) AJC-14176 Detection, distribution and assessment of environmental impacts of covered mine ores uses biogeochemical methods in addition to geochemical methods. This study analyzed environmental effects of mineralization and mining activities on plants, using biogeochemical methods. The study also determined spatial distribution of biogeochemical parameters by modeling through geochemical and geostatistical methods. The study used Astragalus sp., Berberis vulgaris, Colutea cilicia, Juniperus oxycedrus, Paliurus spina-christi, Pinus nigra, Rosa canina plant species, which are abundant and widely distributed in the region. It was found that among plant species, branch of Juniperus oxycedrus were found to be indicators for Pb (r = 0.7541; p = < 0.01; n = 15) and branch of Pinus nigra were found to be indicators for Zn (r = 0.79; p = < 0.01; n = 13). Analyses showed that metal accumulation varied in each plant. It was observed that biologic absorption coefficients corresponded to strong absorption (BAC = 1-10) values in Zn and Pb elements. Key Words: Biogeochemistry, Multi-element analysis, Indicator plants, Environmental impact, Juniperus oxycedrus, Pinus nigra. Asian Journal of Chemistry; Vol. 25, No. 16 (2013), 9351-9355 http://dx.doi.org/10.14233/ajchem.2013.15563 poisonous elements in their bodies at high ratios. They can also transfer those elements to other living things, which consume milk and meat of these animals in their daily diet 1 . Madenköy (Nigde/Ulukisla) and its vicinity, which is rich in lead-zinc mineralization was called “Bulgarmaden” in ottoman period. Records of antique mining traces and slag masses which are thought to belong antiquity are found since 19. Century Pb-Zn-Cu-Au-Ag deposits in Bolkar Mountains are considered to be exploited by Hittites, Byzantium and Romans. In addition, it was reported that ore mined in other regions were brought and smeltered in Madenköy 11 . This study analyzed environmental effects of minerali- zation and mining activities in the region on plants using bio- geochemical methods. The study aimed to analyze indicator plants for each element by identifying heavy metal (Al, Fe, Mn, Pb, Cu, Zn) contents in plant and soil based on abundant and widely distributed plant species (Astragalus sp., Berberis vulgaris, Colutea cilicia, Juniperus oxycedrus, Paliurus spina- christi, Pinus nigra, Rosa canina) and soil samples in the region 12 . This paper included biogeochemical behaviours of Juniperus oxycedrus and Pinus nigra plant species. EXPERIMENTAL A total of 83 abundant and widely distributed plant (Astragalus sp., Berberis vulgaris, Colutea cilicia, Juniperus