Description: © The Author(s), 2014]. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Scientific Reports 4 (2014): 6648, doi:10.1038/srep06648.

Description: Sediments from Tibetan lakes in NW China are potentially sensitive recorders of climate change and its impact on ecosystem function. However, the important plankton members in many Tibetan Lakes do not make and leave microscopically diagnostic features in the sedimentary record. Here we established a taxon-specific molecular approach to specifically identify and quantify sedimentary ancient DNA (sedaDNA) of non-fossilized planktonic organisms preserved in a 5-m sediment core from Kusai Lake spanning the last 3100 years. The reliability of the approach was validated with multiple independent genetic markers. Parallel analyses of the geochemistry of the core and paleo-climate proxies revealed that Monsoon strength-driven changes in nutrient availability, temperature, and salinity as well as orbitally-driven changes in light intensity were all responsible for the observed temporal changes in the abundance of two dominant phytoplankton groups in the lake, Synechococcus (cyanobacteria) and Isochrysis (haptophyte algae). Collectively our data show that global and regional climatic events exhibited a strong influence on the paleoecology of phototrophic plankton in Kusai Lake.

Description: This research was supported by grants from the National Natural Science Foundation of China (Grant Nos. 41030211 and 41302022), the National Basic Research Program of China (Grant No. 2011CB808800), and State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Nos GBL11410 and GBL11201).

Description: An anaerobic nitrate-reducing Fe(II)-oxidizing bacterium, Pseudogulbenkiania sp. strain 2002, was used to investigate As immobilization by biogenic Fe oxyhydroxides under different initial molar ratios of Fe/As in solutions. Results showed that Fe(II) was effectively oxidized, mainly forming lepidocrocite, which immobilized more As(III) than As(V) without changing the redox state of As. When the initial Fe/As ratios were kept constant, higher initial Fe(II) concentrations immobilized more As with higher Asimmobilized/Feprecipitated in biogenic lepidocrocite. EXAFS analysis showed that variations of initial Fe(II) concentrations did not change the As–Fe complexes (bidentate binuclear complexes (2C)) with a fixed As(III) or As(V) initial concentration of 13.3 μM. On the other hand, variations in initial As concentrations but fixed Fe(II) initial concentration induced the co-occurrence of bidentate binuclear and bidentate mononuclear complexes (2E) and bidentate binuclear and monodentate mononuclear complexes (1V) for As(III) and As(V)-treated series, respectively. The coexistence of 2C and 2E complexes (or 2C and 1V complexes) could contribute to higher As removal in experimental series with higher initial Fe(II) concentrations at the same initial Fe/As ratio. Simultaneous removal of soluble As and nitrate by anaerobic nitrate-reducing Fe(II)-oxidizing bacteria provides a feasible approach for in situ remediation of As-nitrate cocontaminated groundwater.

Description: Sustainability, Vol. 10, Pages 3325: Influence of Livelihood Capitals on Livelihood Strategies of Herdsmen in Inner Mongolia, China Sustainability doi: 10.3390/su10093325 Authors: Wenqiang Ding Saheed Olaide Jimoh Yulu Hou Xiangyang Hou Weiguo Zhang Herders’ living strategy is a function of the capitals at their disposal which also serve as a buffering mechanism when shocks arise. An insight into the connection between livelihood strategies and capitals owned by herders provides guidance to recognize their living situation. This study evaluated the different livelihood capitals of herders across the five ecological types (meadow, typical, desert, sandy, and desert steppe) in Inner Mongolia region of China, using the sustainable livelihood framework approach. An evaluation index was developed and used to investigate how the livelihood capitals of herders affects preferential selection of livelihood strategies using multinomial logit model. Results indicate that: (1) The stocks of human and social capitals were higher while those for natural, physical, and financial capitals were lower. (2) There were significant regional differences in the livelihood capital stock of herders’ families with zonal horizontal decrease from east to west. (3) Natural capitals affects the preferential selection of livelihood strategies by herders positively implying that possession of more natural capitals by herders leads to selection of livelihood strategies that are devoid of pastoral production; the preferred livelihood strategy of herders was significantly negatively affected by physical and financial capitals, an indication that, when herders possess more physical and financial capitals, they tend to choose livelihood strategies that involve pastoral production. The living strategy of herders was not affected by human and social capitals. (4) Production of rented pasture capital index affected the preferential selection of livelihood strategies by herders positively while cash income capital index had negative influence on how pastoralists select their livelihood strategies. In conclusion, the total livelihood capital of herders in Inner Mongolia is low, and there is perceived benefit in the differentiation of herders families into petty-herders and non-grazing families from the perception of natural resource management and sustainability. This requires income diversification programs such as capacity building and business education that will aid the smooth transition of households to these less resource exploiting livelihood strategies.