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1

Dynamics of changes in sparingly soluble Al, Fe, Mg, Zn, and Cu phosphates in the presence of urea in aqueous solution and in soil

100%

Szymkiewicz-Dabrowska D.

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2000

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tom 04

2

Phosphorus forms in organic soils with a varying degree of transformation [on the example of the Lublin Polesie region]

84%

Ziolek M.

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nr 2

179-194

EN

The aim of the present study was to evaluate the content of various phosphorus forms in organic soils with various transformation degrees as well as to determine the distribution of the total phosphorus pool into its individual soil forms along with their location in the soil profiles. Three soil profiles originating from peats and collected from areas subjected to the influence of various human activities, located in the Lublin Polesie region, were the subject of the present research. A method of sequential phosphorus fractioning was applied. Three fractions of inorganic phosphorus: Pi-L – labile inorganic P, loosely adsorbed; Pi-FeAl – inorganic P associated with Fe and Al; Pi-CaMg – inorganic P associated with Ca and Mg; and two fractions of organic phosphorus: Po-HuAc – organic P associated with fulvic and humic acids, and Po-Res – residual organic P. The following conclusions can be drawn from the present research: in the soils from the areas strongly transformed by man (completely dehydrated and with an advanced muck formation process) accumulation of total phosphorus in the upper part of the soil profile takes place, accompanied by a decrease of organic forms content and an increase in the share of inorganic phosphorus forms; forest peat soil not subjected to a direct influence of human activities was characterised by a very high total phosphorus content; the distribution of the total phosphorus pool into individual fractions in organic soils mainly depends on natural conditions such as: peat-bog character, carbonates content, and pH.

PL

Celem pracy było zbadanie zawartości różnych form fosforu w glebach organicznych o różnym stopniu przeobrażenia oraz określenie rozkładu puli fosforu całkowitego na poszczególne jego formy glebowe i ich rozmieszczenie w profilach. Badaniami objęto 3 profile gleb wytworzonych z torfów,pobrane z obszarów poddanych różnorodnym wpływom działalności człowieka, zlokalizowane na Polesiu Lubelskim. W badaniach zastosowano metodę sekwencyjnego frakcjonowania fosforu, w wyniku której uzyskano trzy frakcje P nieorganicznego: Pi-L – fosfor nieorganiczny łatwo rozpuszczalny (labilny), Pi-FeAl – fosfor nieorganiczny związany z Fe i Al, Pi-CaMg – fosfor nieorganiczny związany z Ca i Mg, oraz dwie frakcje P organicznego: Po-HuAc – fosfor organiczny związany z kwasami humusowymi i Po-Res – fosfor organiczny w pozostałości. Z przeprowadzonych badań wynikają następujące wnioski: w glebie pochodzącej z obszaru silnie przekształconego przez człowieka (całkowicie odwodnionej, z zaawansowanym procesem murszotwórczym) ma miejsce kumulacja fosforu całkowitego w górnej części profilu, jak też spadek zawartości form organicznych i wzrost udziału form nieorganicznych fosforu; gleba torfowa leśna,nie poddana bezpośrednim wpływom działalności człowieka charakteryzuje się bardzo dużą zawartością fosforu całkowitego;rozkład puli fosforu całkowitego na poszczególne frakcje w glebach organicznych zależy głównie od czynników naturalnych: charakteru torfowiska, zawartości węglanów i pH.

3

Soil acid phosphomonoesterase activity and phosphorus forms in ancient and post-agricultural black alder [Alnus glutinosa (L.) Gaertn.] woodlands

67%

Orczewska A. , Piotrowska A. , Lemanowicz J.

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nr 2

EN

Black alder, an N-fixing tree is considered to accelerate the availability of phosphorus in soils due to the increased production of phosphatase enzymes, which are responsible for the P release from the litter. Acid phosphatase activity plays a pivotal role in organic P mineralization in forest soils and in making P available to plants. In order to check whether Alnus glutinosa stimulates acid phosphomonoesterase (PHACID) activity, we compared enzyme activities, total P concentration (PTOT), plant-available P (PAVAIL), organic P (PORG) and inorganic P (PINORG), and organic matter content in 27 ancient and 27 post-agricultural alder woods (the latter ones representing different age classes: 11-20, 21-40 and 41-60 years) of soil samples taken from the litter and the mineral layers. Phosphomonoesterase activity, organic matter, PTOT, PINORG and PORG concentrations were significantly higher in ancient alder woods than in the soils of post-agricultural forests. Significant differences in the acid phosphatase activity, organic matter and PAVAIL concentration were noted between the litter and mineral layers within the same forest type. In recent stands the amount of organic matter and phosphatase activity increased significantly with the age of alder stands, although only in the mineral layer of their soils. Phosphomonoesterase activity, organic matter and PAVAIL content were higher in a litter layer and decreased significantly at a mineral depth of the soil. The acid phosphatase activity was significantly correlated with organic matter content in both ancient and recent stands. There was no significant relationship between PHACID activity and any P forms.

4

The variability in concentrations of chosen nitrogen and phosphorus forms in the Oder River estuary in 1999-2002

59%

Torz A. , Nedzarek A.

Oceanological and Hydrobiological Studies

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2010

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tom 39

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nr 3