4 results about "Primary productivity" patented technology

The application provides a land ecosystem gross primary productivity determination method and system, and the method comprises the following steps: collecting historical eco-hydro-meteorological data and measured values of land ecosystem gross primary productivity in a research area; constructing a generalized water-energy complementary gross primary productivity model, wherein the generalized water-energy complementary gross primary productivity model comprises a comprehensive coordination index, an energy limitation correction parameter and an available water amount correction parameter, the water amount limitation reference productivity and the energy limitation reference productivity are nonlinearly coupled by the comprehensive coordination index, the energy limitation correction parameter and the available water amount correction parameter; calibrating the comprehensive coordination index, the energy limitation correction parameter and the available water amount correction parameter; inputting the to-be-calculated eco-hydro-meteorological data into the generalized water-energy complementary gross primary productivity model after parameter calibration, and obtaining the target land ecosystem gross primary productivity. The application improves the estimation accuracy of the gross primary productivity.

This invention provides a spatial simulation method for regional crop yield based on remote sensing water-carbon coupling processes. Driven by remotely sensed soil moisture data and multi-source meteorological data, this method constructs a coupled iterative framework of crop growth, remote sensing water-carbon coupling, and water balance modules. It achieves regional-scale spatial simulation of crop leaf area index, evapotranspiration, total primary productivity, and crop yield at a fixed time scale. The spatial distribution of crop yield is obtained by cumulatively calculating total primary productivity over the crop's growth period. This invention does not rely on field sample data, can reflect spatial differences in crop yield within a region, and is suitable for regional agricultural productivity assessment and agricultural drought impact analysis.

The application is a diagnosis method for the response of large-scale river net primary productivity to diurnal temperature difference, and the steps are as follows: reconstructing the data set, constructing the time series input index and constant input index; screening the net primary productivity data of high-quality rivers, and calculating the monthly average value as the output index; using the random forest model to construct the prediction model of large-scale river net primary productivity, and using the network iterative optimization method to obtain the optimal model parameters; driving the trained random forest model to obtain the prediction data of river net primary productivity under different diurnal temperature differences and corresponding daily average water temperature; calculating the difference between the maximum value of net primary productivity and the current prediction data to determine the optimal temperature difference; comparing the current diurnal temperature difference with the optimal temperature difference to calculate the increment of fluctuation amplitude and the respiratory carbon emission. The application determines the response function of river net primary productivity to diurnal temperature difference change through the control experiment, and reveals the influence mechanism of diurnal asymmetric warming on net primary productivity.

The application discloses a kind of in-situ measurement methods of aquatic primary productivity based on fluorescence excitation spectrum three-wavelength fitting model, belong to environmental monitoring and aquatic ecosystem technical field.The application includes: in-situ collection target water body water sample and filter to remove large particle impurities;Water sample is moved into fluorescence spectrophotometer sample cell, and after dark chamber balancing, the fluorescence intensity of 438nm, 485nm, 624nm three characteristic wavelengths is measured;According to water sample type, the integral area of fluorescence excitation spectrum is calculated using corresponding first-order linear fitting equation;Through the correlation model of integral area and primary productivity, the primary productivity of target water body is calculated.The application does not need sample pretreatment, simple and fast, measurement period is ≤30min, realizes in-situ non-invasive monitoring;Cover a variety of photosynthetic pigment characteristic absorption peak, wide application range, can tolerate a variety of stress conditions;Measurement precision is high, sensitivity is strong.