Soil phosphorus and potassium availability in long-term field experiments with organic and mineral fertilization

Soil samples (from Czech and German long-term field experiments) were used to estimate different soil phosphorus (P) fractions. More than 200 topsoil (0–30 cm) samples from different fertilizing treatments were taken. These were analyzed for P in soil solution (PCaCl2) [0.01M CaCl2 extract], exchangeable sorbed P (Pex) [anion exchange (AE) membranes] and bioavailable P [Doppel-Lactat and Mehlich 3 (PDL and PM3)]. Other fractions analyzed were total inorganic (Pin), total (PM-tot) and organic (Porg) P [fractionation after Marks], P sorbed on Fe and Al (PFeAl) [fractionation after Schwertmann] and residual P (Par) [aqua regia extract]. Comparison of medians appeared to be better for evaluating extraction abilities. Phosphorus fractions were in the following order: (Par = 100%); PCaCl2 (0.2%) < Pex (9%) < PDL (10%) < PM3 (16%) < Pin (24%) < Porg (37%) < PFeAl (55%) < PM-tot (59%). Low amounts of Pin, Porg and PM-tot did not verify the applicability of the Marks’ fractionation for the set of studied soils. Close correlations at P ≤ 0.001 were found for all methods for estimating the fractions of bioavailable phosphates (PCaCl2, Pex, PDL and PM3). Statistically significant relations were observed between Pin with Par, PM-tot and PFeAl.

Download Full-text

Different soil fertility conditions depending on different land use methods

Acta Agraria Debreceniensis ◽

10.34101/actaagrar/49/2518 ◽

2012 ◽

pp. 169-172

Author(s):

Sándor Hoffmann

Keyword(s):

Soil Fertility ◽

Field Experiments ◽

Farmyard Manure ◽

Optimum Level ◽

Mineral Fertilization ◽

Yield Data ◽

Npk Fertilizers ◽

Local Climate ◽

Term Field

In precision nutrient management the most important aspect is adaptation but we should consider the possibility of the long-term improvement of soil fertility within the less fertile landscape zones. This possibility can be evaluated principally by long-term field experiments, which are running on similar soil types. The results of these field experiments can indicate that which soil fertility status should be attained. Some more important soil fertility data, (such as pH, P-, K- and soil organic matter (SOM) content) of a long-term field experiment with increasing farmyard manure(FYM) doses or equivalent NPK fertilizers, set up on an Eutric cambisol, are presented. The yieldincreasing capacity of FYM doses was only 82%, as compared to the equivalent amount of mineral NPK, but long-term FYM treatments resulted in 10% higher SOM content than that of equivalent NPKfertilizer doses. The studies indicate that SOM content is a function of local climate and clay content of the soil, and neither long-term high FYM doses can increase SOM content steadily above a supposed steady-state value. However we have to make efforts to keep the optimum level. The lowest soil reactions developed both with the highest NPK doses and without any fertilization. AL-P2O5 content of soil was increased more by mineral fertilization than by FYM treatments, but in case of AL-K2O content there was no difference between the fertilization variants. However the highest doses of both fertilization variants increased soil nutrient content to an excessive degree. Wecould get very valuable data from the unfertilized control plots as well, where long-term yield data suppose 48 kg ha-1 year-1 air-borne N-input.

Download Full-text

Build up and depletion of soil phosphorus and potassium and their uptake by rice and wheat in a long-term field experiment

Plant and Soil ◽

10.1007/bf02181784 ◽

1986 ◽

Vol 91 (2) ◽

pp. 161-170 ◽

Cited By ~ 14

Author(s):

Anand Swarup ◽

R. K. Chhillar

Keyword(s):

Field Experiment ◽

Soil Phosphorus ◽

Phosphorus And Potassium ◽

Term Field

Download Full-text

УРОЖАЙНОСТЬ САХАРНОЙ И ЛОПАЮЩЕЙСЯ КУКУРУЗЫ ПРИ ВОЗДЕЛЫВАНИИ БЕССМЕННО И В СЕВООБОРОТАХ

Вісник Полтавської державної аграрної академії ◽

10.31210/visnyk2014.04.07 ◽

2014 ◽

pp. 44-47

Author(s):

С. В. Маслиёв

Keyword(s):

Winter Wheat ◽

Field Experiments ◽

Sweet Corn ◽

Crop Rotations ◽

Field Crop ◽

Vegetable Crop ◽

Mineral Fertilization ◽

Corn Cobs ◽

Term Field

Подано результати багаторічних польових дослі-дів про урожайність початків цукрової та зерна роз-лусної кукурудзи різних сортів і гібридів залежно відпопередників у польових та овочевих сівозмінах, атакож беззмінних посівах. Надані рекомендації повнесенню мінеральних добрив та строків сівби.Установлено, що кращими попередниками для цихпідвидів кукурудзи в польових сівозмінах є горохо-вівсяна суміш на зелений корм та пшениця озима піс-ля пару, а в овочевих – огірки, цибуля, томати, раннякартопля та кабачки, після яких урожайність почат-ків цукрової кукурудзи досягає 8,5–9,5 т/га, зерна роз-лусної – 2,2–2,9 т/га. The results of long-term field experiments of the yield of sweet corn cobs and popcorn grains of various sorts and hybrids, depending on the precursors in field and vegetable crop rotations and also permanent sowing are shown. The recommendations on applying mineral fertilization and terms of sowing are given. It is found that the best precursors for these subspecies of corn in field crop rotations are a mixture of peas and oat for green nutriment and winter wheat after steam, and in vegetable crop rotations the best are cucumbers, onions, tomatoes, early potatoes and zucchini, after which the yield of sweet corn cobs reaches 8,5 -9,5 t / ha and popcorn grains – 2,2-2,9 t / ha.

Download Full-text