Increased inputs of phosphorus (P) and heavy metals to agricultural soils have caused considerable concern. Information on accumulation and chemical forms of the elements in soils is needed as a guide for the judicious application of agricultural chemicals and organic manures. The focus of this study was to assess accumulation of P and heavy metals among various fractions of a sandy soil with a...

The phosphorus activation coefficient (PAC, the ratio of available P to total P) is an important indicator of soil P availability and the transformation of P fractions. Understanding the details of the PAC is useful to estimate soil available P status and to provide P management guidance. In this research, soils from five long-term (23 years) fertilization treatments in three croplands were sel...

The isotopic signature of oxygen in phosphate (δ(18)O(P)) of various soil fractions may shed light on P transformations, including phosphorus (P) recycling by soil microorganisms, uptake by plants and P adsorption, precipitation and release by oxides and minerals, thus increasing our understanding on P cycling and lability in soils. We developed and tested a protocol to extract and purify inorg...

Because land application of broiler litter is commonly made in the spring before cropping season and in the fall, it is essential to understand how environmental variations, such as temperature, affect the phosphorus (P) dynamics. A laboratory incubation study was conducted at Waste Management and Forage Research Unit, USDAARS with the objective of determining the effects of temperature and soi...

The Water-Fluctuation-Zone (WFZ) of the Three Gorges Reservoir (TGR) has a special combination of aquatic and terrestrial ecological systems that are exposed to human activity. In this work, three kinds of soil were sampled along the Yangzi River in the TGR-WFZ. Our study focused on phosphorus (P) sorption characteristics and the change in inorganic P fractions for soils in alternately waterlog...

Quantification of dynamics of soil organic carbon (SOC) pools under the influence of long-term fertilization is essential for predicting carbon (C) sequestration. We combined soil chemical fractionation with stable C isotope analyses to investigate the C dynamics of the various SOC pools after 25 years of fertilization. Five types of soil samples (0-20, 20-40 cm) including the initial level (CK...

The loss of phosphorus (P) during the early pedogenesis stage is important at the ecosystem level, and it also plays an important role in the global P cycle. The seasonal variation of total P (Pt) and its fractions along a young soil chronosequence (Hailuogou chronosequence) on the eastern slope of Gongga Mountain, SW China, was investigated based on the modified Hedley fractionation technique ...

Invasions by alien plants can alter biogeochemical cycles in recipient ecosystems. We test if Early Goldenrod (Solidago gigantea) alters P fractions. To that end, we compare invaded plots and adjacent, uninvaded resident vegetation for specific fractions of organic and inorganic P, phosphomonoesterase (PME) activity in topsoil, and immobilization of P in aboveand belowground organs and in soil ...

Phosphorus losses by surface runoff from agricultural lands have been of public concern due to increasing P contamination to surface waters. Five representative commercial citrus groves (C1–C5) located in South Florida were studied to evaluate the relationships between P fractions in soils, surface runoff P, and soil phosphatase activity. A modified Hedley P sequential fractionation procedure w...

Effects of different fertilizers on organic carbon (C) storage and turnover of soil fractions remains unclear. We combined soil fractionation with isotope analyses to examine soil organic carbon (SOC) dynamics after 25 years of fertilization. Five types of soil samples including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, N; balanced inorganic fertil...