Nutrients and the soil, Biology

Nutrients and the Soil

Early experiments on mineral uptake were performed by Hoagland, Stout and Amon in 1923. They showed that minerals were taken up from the soil primarily in ionic form. The rate of uptake of different ions by roots varied and one ion influenced the uptake of other ions. As soil is the medium for the storage and exchange of mineral ions, its properties, ion exchange capacity, pH and the presence of different cations and anions affect the availability of ions to the plant. In other words, the presence of a certain mineral ions in abundance in the soil cannot ensure its availability to the plant because ions may adhere to clay or precipitate out of the solution as insoluble salts. The soil with high water holding capacity generally has high mineral holding capacity as well.

 

1606_Nutrients and the Soil.png

The fine particles of clay and humus possess a relatively large surface to volume ratio and are negatively charged. Hence, they have higher ion-binding capacity than the soil composed of coarse particles. Figure shows the colloidal clay crystals (micelles) with innumerable negative surface charges. The cations are loosely bound to negative charges by ionic bond and are capable of exchanging rapidly and reversibly with those in the soil solution. H+ ions have greater affinity for charged soil particles than ca2+, Mg2+or K+ ions. Therefore, these cations are released in soil water by H+ ions and made available for uptake by roots. The acidity of soil also increases due to respiration because CO2 released reacts with soil water to form carbonic acid.

Posted Date: 1/17/2013 2:26:09 AM | Location : United States







Related Discussions:- Nutrients and the soil, Assignment Help, Ask Question on Nutrients and the soil, Get Answer, Expert's Help, Nutrients and the soil Discussions

Write discussion on Nutrients and the soil
Your posts are moderated
Related Questions
Explain the Management of Eating Disorders? We shall consider the components of the management of anorexia nervosa and bulimia nervosa together, since the nutritional consequen

SE X DIFFERENTIATION MECHANISM - Primitive gonads are identical in both sexes upto 6 weeks of gestation pressure. This gonad is known as bipotential primordial gonad. It

Task: Write a maximum of five (5) pages of your research plan which should include details on the following topics as appropriate to your chosen study design: I. Background info

Benefits of Cross-Pollination Because of the specific benefits of cross-pollination, flowering plants have evolved many devices to prevent self-pollination and to encourage cr

How do white cells differ from red cells (a) In their structure, (b) Their function?   a) White cells have nuclei, red cells do not have nucle

Explain the Principles of Taxonomy? The goal of taxonomy is to develop a workable classification that reflects evolutionary relationships and provides identification and no

Q. What we need Undergloves? These are a cotton glove worn under the treatment glove for those operators experiencing discomfort to the skin on the hands. These must be replace

Explain Counter Stain - Ziehl-Neelsen Method? Methylene blue is used to stain previously decolourized cells. All non acid-fast bacteria de-stained by acid alcohol now absorbs c

In a properly functioning negative feedback system, the A. value of the controlled variable will always be very close to the threshold value when the system is in steady state.

differences regarding Tiger Planaria and the Iridescent Phyllodoce