TL;DR: In this article, the authors developed and tested a sequential extraction procedure (SEP) for As by choosing extraction reagents commonly used for sequential extraction of metals, Se and P, including NH 4 NO 3, NaOAc, NH 2 OH·HCl, EDTA, NH 4 OH and NH 4 F, were shown to either have only low extraction efficiency for As, or to be insufficiently selective or specific for the phases targeted.
TL;DR: Two types of striated muscle fibers (Padykula amid Herman) can be distimiguished and these have been described as the less active type I and the more active type II fibers.
Abstract: demomistnatiomi of ademiosi mie tn phosphatase ac tivity, two types of striated muscle fibers (Padykula amid Herman. J. Histochem. Cylochem 3: 170. 1955) can be distimiguished. These have been described as the less active type I and the more active type II fibers. It has beemi noted previously (Brooke amid Kaiser. J. Histochem. Cytochem. 17: 431. 1969; (uth amid Samaha. Exp. Neur. 25: 138. 1969) that the ademiosimie triphosphatase (ATPase) systems imi striated muscle fibers have diffenemit
TL;DR: In this article, a quantitative degradation index that is directly related to the reactivity of the organic material, as indicated by its lability to enzymatic decay and its first-order degradation rate constant, was derived.
Abstract: Examination of amino acids in particulate samples from a variety of marine environments (fresh phytoplankton to deep-sea sediments) revealed systematic compositional changes upon progressive degradation. These consistent trends have been used to derive a quantitative degradation index (DI) that is directly related to the reactivity of the organic material, as indicated by its lability to enzymatic decay and its first-order degradation rate constant. This direct link between molecular composition and degradation rate allows us to quantify the quality of organic matter based solely on its chemical composition.
TL;DR: In this paper, the effect of oxygen on the degradation rate of sedimentary organic matter is investigated, and it is shown that the extent of long-term decomposition of organic material is smaller under oxygenated or anoxic conditions alone, than when the material is exposed to the repeated activities of both oxic and anoxic microorganisms.
TL;DR: In this paper, degraded red soil was amended with three different rates (0.5, 1.0 and 2%) of oak wood biochar (W 0.5, W 1.5 and B 0.0 ), with control as 0%.
Abstract: To evaluate the changes in the pool of organic carbon fractions, aggregate stability and activity of enzymes, degraded red soil was amended with three different rates (0.5, 1.0 and 2%) of oak wood biochar (W 0.5 , W 1.0 , W 2.0 ) and bamboo biochar (B 0.5 , B 1.0 , B 2.0 ), with control as 0%. After 372 days, the incubated soils were analyzed for total organic C (TOC), potassium permanganate oxidizable C (POXC), light fraction organic C (LFOC), water soluble organic C (WSC), hot-water extractable C (HWC) and microbial biomass C (MBC), macroaggregates (> 0.25 mm), dehydrogenase, β-glucosidase and urease. The highest macroaggregates, POXC, LFOC, HWC, MBC and enzyme activities were measured in the lowest rates (W 0.5 and B 0.5 ). MBC positively correlated with all labile organic C and macroaggregates, indicating that microbial activities result in mineralization of organic matter (OM) and contribute on bonding agent for macroaggregation. The C/N of the experimental soil negatively correlated with most of labile organic carbons and macroaggregates, which could be the effect of limited N availability on labile organic carbon fraction and aggregation. As compared to the control, lability index (LI) (changes in the lability of soil carbon) increased in W 0.5 and B 0.5 by 4 and 6%, respectively, whereas the carbon management index (CMI) (changes of the total carbon in the soil and its lability) increased by ranges of 50 to 286% in the treatments, and implies sequestration of organic C in soil. The high CMI is largely caused by high C sequestration and low lability differences between the treatments. Our results suggest that biochar application increases total organic carbon, stimulates microbial activities, in turn increases macroaggregation, and thus soil quality.