Estimation and Climate Impact Analysis of Terrestrial Vegetation Net Primary Productivity in China from 2001 to 2020

Abstract

The net primary productivity (NPP) of vegetation is an important indicator reflecting the vegetation dynamics and carbon sequestration capacity in a region. In recent years, China has implemented policies to carry out ecological protection. To understand the changes in the distribution of vegetation NPP in China and the influence of climate factors, the Carnegie–Ames–Stanford approach (CASA) model was used to estimate the NPP from 2001 to 2020. In this paper, several sets of measurement datasets and products were collected to evaluate the effectiveness of the model and suggestions were provided for the modification of the CASA model based on the evaluation results. In addition to the correlation analysis, this paper presents a statistical method for analyzing the quantitative effects in individual climatic factors on NPP changes in large regions. The comparison found that the model has a better estimation effect on grassland and needleleaf forest. The estimation error for the evergreen needleleaf forest (ENF) and deciduous broadleaf forest (DBF) decreases with the warming of the climatic zone, while the evergreen broadleaf forest (EBF) and deciduous needleleaf forest (DNF) do the opposite. The changes in total CASA NPP were consistent with the trends of other products, showing a dynamic increasing trend. In terms of the degree of correlation between the NPP changes and climatic factors, the NPP changes were significantly correlated with temperature in about 10.39% of the vegetation cover area and with precipitation in about 26.92% of the vegetation cover area. It was found that the NPP variation had a negative response to the temperature variation in Inner Mongolia grasslands, while it had a positive but small effect (±10 g C) in the Qinghai–Tibet Plateau grasslands. Precipitation had a facilitative effect on the grassland NPP variation, while an increase in the annual precipitation of more than 200 mm had an inhibitory effect in arid and semi-arid regions. This study can provide data and methodological reference for the ecological assessment of large-scale regional and climate anomalous environments.

Study on Forest and Grassland Ecological Space Structure in Eyu Mining Area and Potential Alternatives for Enhancing Carbon Sequestration

“…Building on previous research [3], this study proposes a novel method to enhance the carbon sequestration capacity of forest and grassland ecological spaces by investigating the coupling coordination between connectivity and carbon sequestration in their structural organization. Despite the fact that planting trees and grass can increase carbon sequestration, there are still some issues to be considered, such as whether the natural environment (soil, climate, etc.)…”

“…Among the various measures aimed at mitigating climate change, carbon sequestration has garnered substantial attention [2]. Nevertheless, mining activities in mining areas constitute one of the primary anthropogenic factors responsible for the colossal annual global carbon emissions [3]. The mining industry is estimated to contribute between 1.9 × 10 12 and 5.1 × 10 12 tons of carbon emissions annually, accounting for approximately 28% of the global carbon emissions and significantly impacting the global carbon budget [4].…”

Quantitative Assessment of the Impact of the Three-North Shelter Forest Program on Vegetation Net Primary Productivity over the Past Two Decades and Its Environmental Benefits in China

“…Vegetation NPP denotes the aggregate organic matter generated by green plants via photosynthesis and carbon dioxide absorption per unit area and time, subtracting the organic matter retained post-autotrophic respiration [3,4]. It is a pivotal element in terrestrial ecosystems for gauging carbon sequestration potential and evaluating ecosystem integrity [5][6][7][8]. Simultaneously, it serves as one of the indicators reflecting ecosystem provisioning capacity.…”

Spatiotemporal Dynamics and Influencing Factors of Vegetation Net Primary Productivity in the Yangtze River Delta Region, China

“…Terrestrial ecosystems have a robust capacity for carbon sequestration and can sequester atmospheric CO 2 as organic compounds through photosynthesis in vegetation, consequently playing a pivotal role in mitigating anthropogenic carbon emissions and contributing to the global carbon cycle [2,3]. Vegetation Net Primary Productivity (NPP) is defined as the net quantity of photosynthetic organic matter taken in per unit area of vegetation over a specific period, showcasing the vegetation's capability to sequester and convert carbon, and serving as a fundamental element of terrestrial carbon sinks and the global carbon cycle [4][5][6]. Numerous scholars posit that assessing NPP not only characterizes the physiological and ecological condition of vegetation but also mirrors alterations in its carbon sequestration capacity through spatial and temporal transformations [7,8].…”

“…Notably, these methods encompass the Global Production Efficiency Model [11], the Eddy Covariance-LUE Model [12], and the Carnegie-Ames-Stanford Approach (CASA model) [13]. The seamless integration of the CASA model with RS and GIS, coupled with the ease of parameter acquisition, establishes it as a prevalent model known for its high measurement accuracy [6]. For instance, certain researchers conducted studies on NPP assessment in the Tibetan Plateau [14] and central China [15].…”