Assessing Changes in the Value of Forest Ecosystem Services in Response to Climate Change in China

Assessing the responses of ecosystem patterns, structures and functions to drought under climate change in the Yellow River Basin, China

Understanding how ecosystems respond and adapt to drought has become an urgent issue as drought stress intensifies under climate change, yet this topic is not fully understood. Currently, conclusions on the response of ecosystems in different regions to drought disturbance are inconsistent. Based on long MODIS data and observed data, this study systematically explored the relationships between ecosystem patterns, structures and functions and drought, taking a typical climate change-sensitive area and an ecologically fragile area-the Yellow River Basin-as a case study. Drought assessment results revealed that the Yellow River Basin has experienced meteorological and hydrological drought during most of the last two decades, predominantly characterized by medium and slight droughts. The ecosystem patterns and structures changed dramatically as the grassland decreased and the landscape fragmentation index (F) increased with increasing wetness. The annual gross primary productivity (GPP) increased, the water use efficiency (WUE) declined and ecosystem service value (ESV) exhibited a W-shaped increase at the watershed scale, but there were significant regional differences. There were positive correlations between F, GPP, ESV and drought indices, while there was a negative correlation between WUE and drought indices at the watershed scale. Under drought stress, the ecosystem structure in the basin was disrupted, the GPP and ESV decreased, but the WUE increased. Notably, approximately 106 %, 20 %, and 1 % of the maximum reductions in F, GPP, and ESV, respectively, were caused by drought, while the maximum 4 % of WUE increased. Responses of some functions in the wetland and grassland to drought vary from those in other ecosystems. The mechanisms underlying ecosystem responses to drought were further investigated. This study enhances the understanding of these responses and will help stakeholders formulate drought mitigation policies and protect ecosystem health.

The trend of forest ecosystem services assessment in eastern India: a review for future research insights

Ecosystem services (ES) are becoming a burgeoning topic presently playing a crucial role in sustaining human well-being, socioeconomic growth, and addressing environmental management and sustainability. The purpose of our review was to overview research trends of the forest ecosystem services (FES) in eastern India and the research methodologies adopted to evaluate them. To systematically study the FES literature, 127 articles pertaining to the term FES during the period 1991 to 2021 were reviewed through a quantitative analysis. The analytical outcome emphasized (1) the research aspects of FES and its types along with regional distribution, (2) the scenario of FES in eastern India with respect to other ES and India, (3) the quantitative trend of FES research over 30 years period, (4) the employed methodological approaches, and (5) the existing research gaps and prospects. Our findings suggest that the publication numbers are quite low in eastern India, as only 5 peer-reviewed articles were found on FES. The result also indicated that the majority of studies primarily focused on provisioning services (85.03%) and the survey/interview method gained more popularity as a primary data source. Most of the earlier studies employed basic assessments like product values or individual income. We also discussed the advantages as well as limitations of the employed methodologies. These findings further highlight the significance of valuing various FES collectively rather than individually and contribute to providing pertinent information for the FES literature scenario, which may help to strengthen forest management as well.

Ecosystem Service Value Estimation of Paddy Field Ecosystems Based on Multi-Source Remote Sensing Data

A paddy field ecosystem (PFE) is an important component of an agricultural land ecosystem and is also a special artificial wetland with extremely high value. Taking Tianjin (a municipality city in China) as the research area and using multi-source remote sensing data, we improved the accounting framework of the ecosystem service value (ESV) of PFEs and the calibration of model parameters. The ESV of PFEs was mapped at medium-high resolution and fine-grain at the provincial scale. The results showed that: (1) the net ESV of PFEs in Tianjin in 2019 was RMB 29.68 × 108, accounting for 0.21% of GDP. The positive ESV was RMB 35.53 × 108, the negative ESV was RMB 5.84 × 108, and the average ESV per unit area was RMB 5.47 × 104/ha; (2) as a proportion of the ESV of PFE, the value of climate regulation (61.27%) was greater than the value of carbon fixation and oxygen release (15.29%), which was greater than the value of primary products supply (8.08%). The production value of PFEs is far lower than their ESV; (3) the total net ESV in Baodi District was RMB 16.85 × 108, accounting for 56.77% of Tianjin’s ESV, and the net ESV per unit area was RMB 5.72 × 104/ha, both of which were higher than in other districts; (4) the pixel-based hot spots analysis showed that the number of hot spots (high-value ESV) and cold spots (low-value ESV) reached 98.00% (hot spots 56.9%, cold spots 41.1%) with a significant cluster distribution. The hot spots were mostly distributed in Baodi District (37.8%) and the cold spots were mostly distributed in Ninghe District (17.2%). The research results can support agricultural development, improve countermeasures according to local conditions, and provide theoretical support for regional land use planning, ecological compensation policy formulation and ecological sustainable development. Our methodology can be used to assess the impact of land use change on ESV.

Assessment of Ecosystem Services: Spatio-Temporal Analysis and the Spatial Response of Influencing Factors in Hainan Province

The impact of human activities on ecosystems is receiving increasing attention because their mechanisms of action are complex; the spatial response of ecosystem service drivers still needs to be explored further. This study evaluated three ecosystem services—water yield, soil conservation, and carbon storage—in Hainan Province from 2000 to 2020; we analyzed the spatial and temporal changes of the ecosystem services, and the spatial heterogeneity of the influencing factors. The results were as follows: (1) The average water yield, soil conservation and carbon storage of Hainan Province from 2000 to 2020 were 42.36 billion, 8.01×108 t and 1.52 × 107 t, respectively. Overall, the ecosystem services were relatively weak at lower elevations. (2) There were obvious hot spots and cold spots in the water yield and soil conservation, and the hot spot distribution of carbon storage was not obvious. (3) There were differences between the ecosystem services for different land use types; trade-off relationships only appeared between unused land and ecosystem services. (4) The precipitation, normalized difference vegetation index and elevation factors had great impacts on the ecosystem services. Most of the human activity factors showed a significant nonlinear enhancement effect during their interaction. Population and elevation had obvious spatial differentiation effects on the water yield and carbon storage services.

The Spatiotemporal Evolution and Prediction of Carbon Storage in the Yellow River Basin Based on the Major Function-Oriented Zone Planning

Land use/cover change is the main reason for the variation of ecosystem carbon storage. The study of the impact of land use on carbon storage has certain reference values for realizing high-quality development in the Yellow River Basin. In this paper, the InVEST model was used to simulate the variation of carbon storage in the Yellow River Basin in 2000, 2005, 2010, 2015, and 2020, and to predict the carbon storage in 2030 in combination with the CA-Markov model, as well as to discuss the impact of land use on carbon storage. The results showed that: (1) The variation trend of carbon storage for different land use types in the Yellow River Basin was different and was mainly manifested as a decrease of cultivated land and unused land, and an increase of forest land, grassland, water, and construction land. The carbon storage in the provincial key development prioritized zone, national development optimized zone, and provincial development optimized zone showed decreasing trends, while the national key development prioritized zone and national major grain producing zone presented a fluctuating downward trend. (2) The ecosystem carbon storage function weakened after 2000, and part of the carbon sink area transformed into a carbon source area. The area with low carbon storage was distributed in the west of the provincial key ecological function zone, and the area with high carbon storage was concentrated in the south and middle of national key ecological function zone and the east of the provincial key ecological function zone. (3) The carbon loss was largest in the urban expansion scenario (UES), followed by the natural development scenario (NDS) and ecological protection scenario (EPS). The carbon storage of different scenarios presented significant positive correlations with land use intensity.