Abstract: A method for calculating a gross primary productivity of an ecosystem is provided. The application belongs to a technical field of gross primary productivity calculation, and includes: acquiring key parameters of the ecosystem and screening out standard parameters, where the key parameters include a gross primary productivity, a solar altitude angle and an atmospheric column material content; calculating factor parameter terms based on the standard parameters and ground water vapor pressure parameters; where the factor parameter terms include a photochemical term, a scattering term and a gross primary productivity term; and based on the factor parameter terms, acquiring a calculation model of a gross primary productivity through an energy balance principle of a photosynthetically active radiation; through the calculation model, acquiring a calculated value of the gross primary productivity of the ecosystem.

Abstract: A follow-up swing head type large taper wire cutting device is disclosed. In the large taper wire cutting device, swing heads on upper and lower mechanical arms are adjusted in a follow-up way by swing head rotating mechanisms in coordination with a cutting taper, universal wire guide wheels are used to cooperate with the corresponding upper and lower swing heads, and tensioning mechanisms between the universal wire guide wheels and directional wire guide wheels are used for transition to ensure the smooth transition of an electrode wire, so that the electrode wire is effectively prevented from sliding off during large taper cutting, and the control of the follow-up deflection position of the electrode wire is also very accurate.