Know more

Our use of cookies

Cookies are a set of data stored on a user’s device when the user browses a web site. The data is in a file containing an ID number, the name of the server which deposited it and, in some cases, an expiry date. We use cookies to record information about your visit, language of preference, and other parameters on the site in order to optimise your next visit and make the site even more useful to you.

To improve your experience, we use cookies to store certain browsing information and provide secure navigation, and to collect statistics with a view to improve the site’s features. For a complete list of the cookies we use, download “Ghostery”, a free plug-in for browsers which can detect, and, in some cases, block cookies.

Ghostery is available here for free:

You can also visit the CNIL web site for instructions on how to configure your browser to manage cookie storage on your device.

In the case of third-party advertising cookies, you can also visit the following site:, offered by digital advertising professionals within the European Digital Advertising Alliance (EDAA). From the site, you can deny or accept the cookies used by advertising professionals who are members.

It is also possible to block certain third-party cookies directly via publishers:

Cookie type

Means of blocking

Analytical and performance cookies

Google Analytics

Targeted advertising cookies


The following types of cookies may be used on our websites:

Mandatory cookies

Functional cookies

Social media and advertising cookies

These cookies are needed to ensure the proper functioning of the site and cannot be disabled. They help ensure a secure connection and the basic availability of our website.

These cookies allow us to analyse site use in order to measure and optimise performance. They allow us to store your sign-in information and display the different components of our website in a more coherent way.

These cookies are used by advertising agencies such as Google and by social media sites such as LinkedIn and Facebook. Among other things, they allow pages to be shared on social media, the posting of comments, and the publication (on our site or elsewhere) of ads that reflect your centres of interest.

Our EZPublish content management system (CMS) uses CAS and PHP session cookies and the New Relic cookie for monitoring purposes (IP, response times).

These cookies are deleted at the end of the browsing session (when you log off or close your browser window)

Our EZPublish content management system (CMS) uses the XiTi cookie to measure traffic. Our service provider is AT Internet. This company stores data (IPs, date and time of access, length of the visit and pages viewed) for six months.

Our EZPublish content management system (CMS) does not use this type of cookie.

For more information about the cookies we use, contact INRA’s Data Protection Officer by email at or by post at:

24, chemin de Borde Rouge –Auzeville – CS52627
31326 Castanet Tolosan CEDEX - France

Dernière mise à jour : Mai 2018

Menu Logo Principal

Home page

Phosphate fertiliser value

The phosphate levels in residual organic products (OWP) range from 7.3 to 24.2 g/kg DM. The spreading of OWP provides an input of between 97 and 485 kg/ha. GWS compost and manure contain the most phosphorus. The proportion of phosphorus available for plants ranges from 6% to 26%, with manure showing the maximum availability.

Phosphorus levels in OWPs

The total phosphorus (tot P2O5) and Olsen phosphorus (P2O5 Olsen) levels in organic waste products (OWPs) are shown in Table 1.

Table 1. Total phosphorus and Olsen phosphorus levels in g/kg DM in OWPs from 1998 to 2011 (n=8). The figures in brackets indicate the standard deviations.



The total phosphorus levels range from 7.5 to 28.3 g/kg DM, in the following order MSW, BIO < FYM < GWS. Oslen phosphorus, which evaluates the potentially available phosphorus, ranges from 0.5 to 3.3 g/kg DM, in the following order: MSW < BIO < GWS < FYM. The proportion of available phosphorus represents 6% to 26% of the total phosphorus: 6% for MSW and GWS, 9% for BIO and 26% for FYM.

Average phosphorus flows per spreading

The average total and Olsen phosphorus flows are shown in Table 2.

Table 2. Average phosphorus flows per spreading in kg/ha in OWPs from 1998 to 2011 (n=8). The figures in brackets indicate the standard deviations.

Flux P_1998-2011_An_72dpi


Total phosphorus flows range from 97 to 485 kg/ha per spreading, in the following order: MSW < FYM < BIO < GWS. This order is the combined result of phosphorus level in OWPs and the doses that are applied. MSW compost and BIO compost, for example, have similar total phosphorus levels, although the phosphorus flow per spreading for BIO compost is twice as high as that of RMW compost, depending on the dose applied.
When spreading compost on organic matter sparingly, GWS compost provides the most total phosphorus.
Meanwhile, FYM provides the most Olsen phosphorus and therefore the most potentially available phosphorus per spreading. Olsen phosphorus flows range from 6 to 43 kg/ha, in the following order: MSW < BIO < GWS < FYM.

flèche précédent


flèche suivant