P provides the backbone of nucleic acids it is

Info icon This preview shows pages 11–17. Sign up to view the full content.

View Full Document Right Arrow Icon
between N and photosynthesis is particularly strong. P provides the backbone of nucleic acids; it is fundamental to synthesis and growth in cells and organisms.
Image of page 11

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 12
Nutrient Limitation The supply of N and P most often constrains plant productivity in ecosystems terrestrial, aquatic, and marine - as demonstrated by fertilizer experiments in natural systems, and by the widespread and increasing use of N and P fertilizers in agriculture. Animal growth is also frequently protein (N)-limited. Other elements may limit growth as well Ca, Mg, K, and in animals Na are important resources for organisms, and K in particular is #3 in abundance (after N and P) as an agricultural fertilizer
Image of page 13

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Geophysical Context Ecosystems include physical processes as well as biological communities. To understand how terrestrial biota obtain nutrient elements, we have to understand that the most important elements have different sources and dynamics; in terrestrial systems, these can be summarized: Element Source Mobility Abundance in the Ocean Nitrogen Atmosphere High Low Phosphorus Rocks Low Low Cations Rocks High High *by “ cations ” I mean calcium, magnesium, potassium
Image of page 14
In the Hawaiian Islands, land surfaces are created by volcanic eruption and go through what we call “ecological succession” as plants, animals, and microbes arrive and grow and soils develop
Image of page 15

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
What element(s) limit production? Over the first few thousands of years, the volcanic rock dissolves relatively rapidly and releases elements. Later (some hundreds of thousands of years later), nitrogen has accumulated from the atmosphere and all of the rock within reach of plant roots has broken down, leaving an
Image of page 16
Image of page 17
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern