Method for quickly measuring grassland productivity

The invention relates to a method for quickly measuring grassland productivity. The method comprises the following steps of: (1) selecting fixed quadrats, namely arranging 10 fixed quadrats on sample land capable of representing natural grassland vegetation characteristics or on southern and northern slopes according to upper, middle and lower slope directions; after forage grasses turn green, dotting the forage grasses by a GPS (global position system), arranging the fixed quadrats, and making a remarkable mark for each quadrat by angle iron or a wood stick; (2) monitoring the grassland productivity, namely firstly estimating dry green part weight, dry standing dead matter weight and dry litter weight of all forage grasses in the fixed quadrats, secondly estimating a cover degree, thirdly sorting the dry weights in the fixed quadrats, fourthly measuring actual biomasses, namely measuring random quadrats to obtain actual measurement values of the dry litter weight, the dry green part weight and the dry standing dead matter weight respectively, and fifthly building a regression model and correcting according to a fitting degree R2 until R2 is more than 0.8. The method is quick, accurate and efficient, and can be used for achieving the purpose of continuously monitoring grassland for a long term.