Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Changes in soil physicochemical properties. Organic matter (OM) (a), ammonium nitrate content (AN) (b), total nitrogen content (TN) (c), soil pH (d), available phosphate (AP) (e), available kalium (AK) (f), nitrate nitrogen content (NN) (g), total phosphorus content (TP) (h), in the sample of Tibet (Group XZ), Qinghai (Group QH), Gansu (Group GS). Different lowercase letters (a, b, c) indicate a significant difference at p ≤ 0.05.
