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WOS: 000449534900001 Biological indicators allow to define early changes in soil environment due to the impacts in land management over time. This study investigated the effects of long-term (2006-2015) two conventional (CT-1 and CT-2), three reduced (RT-1, RT-2 and RT-3) and a no-till (NT) on soil organic carbon (SOC), microbial biomass carbon (MBC) and beta-glucosidase enzyme activity (BGA) in eastern Mediterranean region, Turkey. Experimental design was randomized complete block with three replications. Results indicated that SOC, MBC and BGA significantly differed among tillage treatments. Non-disturbed soils under NT had nearly 75% higher SOC (8.80 gkg(-1)), 359% higher BGA (207.66 mg PNP kg(-1)h(-1)) and 68% higher MBC (185.9 mg C kg(-1) soil) compared with highly disturbed soils under CT-1 system. The BGA and MBC concentrations under NT were also significantly higher than the three RT treatments. In contrast to BGA and MBC, the SOC contents under RT systems did not differ from that of NT treatment. Higher concentrations of BGA and MBC under NT and partially under RT compared to CT treatments were most likely related to the increased organic matter contents and non-disturbed environmental conditions. Scientific and Technological Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [115 O 353] This research work was carried out with the financial contribution of the Scientific and Technological Council of Turkey (TUBITAK, Grant Number 115 O 353).

Common ragweed invasion poses serious risks to human health, biodiversity and agricultural production throughout the world. Although ragweed has an enormous potential to expand its range in Turkey, studies on ragweed have only concentrated on the Black Sea region. An exploratory survey was conducted to observe the level of ragweed occurrence on the nodes of predecided 10x10km grids in the Thrace region of Turkey. Ragweed populations were observed in 44 out of 129 sites in a wide range of habitats, including roadsides, pastures, agricultural fields and non-agricultural areas. The highest levels of ragweed infestation were recorded in the agricultural fields, followed by the roadsides. The most-invaded crop was sunflower. The sunflower fields had the highest ragweed coverage as well and invasion even resulted in crop failure alongside the field borders. A spatial analysis of the data indicated that ragweed exhibited an aggregated pattern over the Thrace region. Ragweed distribution was not associated with the characteristics of the soils, which had a varying range of pH, electrical conductivity and texture. The results revealed that ragweed invasion can arise as a serious weed problem, interfering with the sustainability of sunflower production in Thrace and other sunflower-producing regions of the country. A high degree of ragweed infestation also will contribute to the pollen level counts for the most crowded cities in the region, posing a serious danger to human health.