Feldspars as a source of nutrients for microorganisms
نویسندگان
چکیده
Phosphorus and nitrogen are essential macronutrients necessary for the survival of virtually all living organisms. In groundwater systems, these nutrients can be quite scarce and can represent limiting elements for growth of subsurface microorganisms. In this study we examined silicate sources of these elements by characterizing the colonization and weathering of feldspars in situ using field microcosms. We found that in carbon-rich anoxic groundwaters where P and N are scarce, feldspars that contain inclusions of P-minerals such as apatite are preferentially colonized over similar feldspars without P. A microcline from S. Dakota, which contains 0.24% P2O5 but ,1 mmol/ g NH , was heavily colonized 4 and deeply weathered. A similar microcline from Ontario, which has no detectable P or NH , was barren of attached organisms and completely unweathered after one year. An4 orthoclase (0.28% P2O5, ;1 mmol/g NH ) was very heavily colonized and weathered, 4 whereas plagioclase specimens (,0.01% P, ,1 mmmol/g NH ) were uncolonized and 4 unweathered. In addition, the observed weathering rates are faster than expected based on laboratory rates. We propose that this system is particularly sensitive to the availability of P, and the native subsurface microorganisms have developed biochemical strategies to aggressively scavenge P (or some other essential nutrient such as Fe31) from resistant feldspars. The result of this interaction is that only minerals containing P will be significantly colonized, and these feldspars will be preferentially destroyed, as the subsurface microbial community scavenges a limiting nutrient.
منابع مشابه
Mineral stimulation of subsurface microorganisms: release of limiting nutrients from silicates
Microorganisms play an important role in the weathering of silicate minerals in many subsurface environments, but an unanswered question is whether the mineral plays an important role in the microbial ecology. Silicate minerals often contain nutrients necessary for microbial growth, but whether the microbial community benefits from their release during weathering is unclear. In this study, we u...
متن کاملResidue of horse serum purification as a nitrogen source for growth of microorganisms, l-Clostridia
متن کامل
Horse serum purification residue as a nitrogen source for the growth of microorganisms, II-Corynebacterium diphtheria (Toxin Production)
متن کامل
The effect of Dietary Fiber Source and Threonine Level on Growth Performance, Nutrients Digestibility and Digesta Characteristics of Broiler Chickens in a Period of 24 Days
The aim of this study was to survey the effect of different dietary fiber source and thereonine levels on growth response, nutrients digestibility and some digesta characteristics of broiler chickens. A total of 180 day-old male Ross 308 chicks were used in a completely randomized design with a factorial arrangement of 2×3 with 4 replicates of 6 birds each for a period of 24 days. The diets co...
متن کاملSilicates, Silicate Weathering, and Microbial Ecology
Mineralogy, microbial ecology, and mineral weathering in the subsurface are an intimately linked biogeochemical system. Although bacteria have been implicated indirectly in the accelerated weathering of minerals, it is not clear if this interaction is simply the coincidental result of microbial metabolism, or if it represents a speci c strategy offering the colonizing bacteria a competitive ec...
متن کامل