Changes In Water Yield Research Articles

Spatiotemporal Evolution and Attribution Analysis of Water Yield in the Xiangjiang River Basin (XRB) Based on the InVEST Model

As a result of climate change and human activities, water resources in the Xiangjiang River Basin (XRB) are subject to seasonal and regional shortages. However, previous studies have lacked assessment of the spatiotemporal evolution of water yield in the XRB at seasonal and monthly scales and quantitative analysis of the driving forces of climate change and land use on water-yield change. Quantitative evaluation of water yield in the XRB is of great significance for optimizing water-resource planning and allocation and maintaining ecological balance in the basin. In this paper, the seasonal water-yield InVEST model and modified Morris sensitivity analysis were combined to study the characteristics of monthly water yield in the XRB. Seventeen attributes were identified using the Budyko framework. The results show that: (1) the water yield of the XRB showed an increase trend from northeast to southwest from 2006 to 2020; (2) the transfer-in of unused land, grassland, woodland and farmland as well as the transfer-out of water and construction land have positive effects on the increase in water yield, and the change to construction land has the greatest impact on water yield; (3) water yield is positively correlated with NDVI and precipitation and negatively correlated with potential evapotranspiration; (4) climate change and land-use change contributed to water-yield changes of 67.08% and 32.92%, respectively.

Spatial Application of Southern U.S. Pine Water Yield for Prioritizing Forest Management Activities

Forest management depends on forest condition data and the ability to quantify the impacts of management activities to make informed decisions. Spatially quantifying water yield (WY) from forests across large landscapes enables managers to consider potential WY changes when designing forest management plans. Current forest water yield datasets are either spatially coarse or too restricted to specific sites with in situ monitoring to support some project-level forest management decisions. In this study, we spatially apply a stand-level southern pine WY model over a forested landscape in the Florida panhandle. We informed the WY model with pine leaf area index inputs created from lidar remote sensing and field data, a spatial and temporal aridity index from PRISM and MODIS data, and a custom depth to groundwater dataset. Baseline WY conditions for the study area were created using the Esri and Python tools we developed to automate the WY workflow. Several timber thinning scenarios were then used to quantify water yield increases from forest management activities. The results of this methodology are detailed (10 m spatial resolution) forest WY raster datasets that are currently being integrated with other spatial datasets to inform forest management decisions.

Estimating Evapotranspiration Using Chloride Mass Balance in a New Mexico Paired Basin Study 2009-2019

A paired basin study in the upper Santa Fe River watershed following forest thinning and prescribed burns successfully measured water budget components in a treated and an untreated (control) basin. The paired basin study was established to investigate questions that have arisen regarding changes in water yield from forest treatments. Precipitation, stream flow, soil moisture, and chloride concentrations in precipitation and stream flow were measured to quantify the water budget components. The results from eleven years of data collection and analysis have a high degree of confidence with respect to measuring the water budget components based on the mass balance of water and chloride. The differences in the geologic structure and topography between the two paired basins appeared to impact the water budgets more than the forest treatments, except during periods when winter precipitation and snowmelt represented a significant component of inflow. Although this paired basin study was not able to portray a simple relationship between forest thinning and water yield, the chloride concentration methodology used to estimate evapotranspiration (ET) was successful. These detailed observations of chloride deposition and transport characteristics may be relevant for other researchers working in forested basins with substantial ET. ET rates were estimated by examining the cycle of chloride entering and exiting each basin over six integration periods. ET was estimated to be about 90% to 94% of precipitation in the treated basin and 77% to 86% in the control basin. The higher ET in the treated basin both before and after forest treatments may be due to the much greater area of west-facing hillslopes in the treated basin, which receive warm afternoon sun, and the greater area of rock cover in the control basin. Variation in the chloride concentration of collected precipitation samples from different sites indicates that horizontal precipitation of chloride in the tree canopy is an important consideration when using the chloride mass balance approach to calculate water budget components.

Ecosystem Services Trade-Offs and Synergies following Vegetation Restoration on the Loess Plateau of China

The Loess Plateau (LP) is a heavily soil-eroded area. Since the year 1999, the Chinese government has carried out the “Grain for Green Project (GGP)” that has focused on increasing the regional vegetation coverage. Understanding the temporal and spatial variation of ecosystem services and the synergy in the LP is important for prospective regional re-vegetation and watershed administration. Therefore, three typical watersheds in the LP were selected: Huangfuchuan, Dalihe, and Yanhe. The spatial and temporal changes in carbon storage (CS), soil conservation (SC), and water yield (WY) in the watersheds were analyzed by the InVEST model from 2000 to 2020. Correlation analysis and root mean square deviation (RMSD) were used to investigate and compare the trade-offs in different ecosystem services (ESs). The results showed that the ES in the Huangfuchuan, Dalihe, and Yanhe watersheds overall developed in a positive direction, and increased from north to south. CS and SC showed a positive correlation in the three watersheds; however, there were negative correlations between CS and WY and between SC and WY. From 2000 to 2020, the trade-offs among CS, SC, and WY in the study area were in the descending order of the Yanhe, Dalihe, and Huangfuchuan watersheds, while the comprehensive benefits were in the opposite order. The results provided an essential basis for the high-quality development and ecological environment preservation of the Yellow River basin.

Significant regime shifts in historical water yield in the Upper Brahmaputra River basin

Abstract. Although evidence of the hydrological response of watersheds to climate change is abundant, reliable assessments of water yield (WY) over mountainous regions, such as the Upper Brahmaputra River (UBR) basin, remain unclear. Here, we examine long-term WY changes during 1982–2013 in the UBR basin, based on multi-station runoff observations. We find that there are significant shifts in hydrological regimes in the late 1990s; WY increases in the range of ∼10 % to ∼80 %, while the directions reverse from increasing to decreasing. Additionally, the double mass curve (DMC) technique is used to assess the effects of climate, vegetation, and cryosphere on WY changes. Results show that cryosphere and climate together contribute to over 80 % of the increase in WY across the entire UBR basin, while the role of vegetation is negligible. The combined effects, however, are either offsetting or additive, thus leading to slight or substantial magnitude increases, respectively. The downward WY trend has primarily been regulated by decreased precipitation in recent years. However, we find that meltwater may alleviate the resulting water shortage in some basins. Therefore, the combined effects of climate and cryosphere on WY should be considered in future water resources management over mountainous basins, particularly involving co-benefits between upstream and downstream regions.

Scale effects on the relationships of water-related ecosystem services in Guangdong Province, China

Study regionGuangdong Province (GD) and the Pearl River Delta urban agglomeration (PRD) in China. Study focusScale is a key factor affecting the connections among ecosystem services, but the relationships between water-related ecosystem services (WRESs) at diverse scales remain unclear. This study evaluated spatio-temporal changes in water yield, water purification and soil retention from 2000 to 2020. The InVEST model was used to depict the WRESs, and correlation analysis was used to detect trade-offs in WRESs at different scales. New hydrological insights for the regioni) The proportion of construction land increased most from 2000 to 2020, especially in the PRD, whereas that of cultivated land and forest exhibited downward trends; ii) During the study period, the three WRESs showed an increase in GD, but water purification and soil retention services showed a decrease in the PRD; iii) for the two scales, trade-offs existed between water yield and other WRESs, and synergies between soil retention and water purification; and iv) The correlation coefficients among WRESs in the PRD were greater than in the whole GD, and the correlation coefficients of the two scales changed in different directions with time. This study expands the scale effect on the relationships among ecosystem services, and puts forward suggestions for the sustainable development of WRESs with consideration of land use planning and stakeholders.

Dynamics and attributions of ecosystem water yields in China from 2001 to 2020

• China’s ecosystem water yield (WYe) increased at a rare of 3.0 mm/yr during 2001 to 2020. • WYe in 61.5%/38.5% of China increased/decreased. • Changes in WYe in 43.6% of China’s regions are dominated by climate change. • Vegetation contributions to WYe changes were highly spatially heterogeneous. • Dominant factors of WYe changes in nine river basins in China were identified. China is plagued by water security and its associated environmental issues under climate change. Clarifying the spatial and temporal changing patterns of ecosystem water yield (WYe) and its driving factors is essential for optimizing climate-resilient development strategies and achieving sustainable development goals. However, the understanding of the spatial and temporal dynamics of WYe changes in China based on continuous time series and their dominant factors has been limited. This creates a challenge to accurately assess water resource dynamics and environmental sustainability under climate change. Therefore, this study explored WYe dynamic trends in China at the grid-scale from 2001 to 2020 based on water balance and remote-sensing datasets. The contribution and dominance of vegetation (leaf area index and net primary productivity), climate (temperature, wind speed, relative humidity, and net radiation), and human activities, were examined. Results showed that WYe changes exhibited an overall increasing trend (3.0 mm/yr, p = 0.1) in China, with 61.5 % and 38.5 % of the regions showing increasing and decreasing trends, respectively. Climate change (dominant area share, 43.6 %) was the primary driver of WYe dynamics in China, followed by vegetation change (23.8 %) and human activities (21.5 %). The dominant driving factors contributing to WYe dynamics in nine river basins were temperature, net primary productivity, net radiation, and relative humidity. The results emphasize that the high spatial heterogeneity of climate-driven WYe changes may exacerbate regional inequalities in water resources. Future vegetation-driven climate intervention programs and ecological restoration should be implemented more cautiously, and regional adaptive programs must be considered to avoid worsening water scarcity further.

Assessing the energy and water balance dynamics of rain-fed rooibos tea crops (Aspalathus linearis) under changing Mediterranean climatic conditions

Rooibos (Aspalathus linearis), a herbal tea crop and a member of the plant family Fabaceae, grows in a narrow ecological range under Mediterranean conditions in South Africa's fynbos biome. There is growing uncertainty on the sustainability of rooibos production under rain-fed conditions in a region which is expected to get warmer and drier in future. No accurate quantitative information currently exists on how the water use, growth and yield of this crop is affected by environmental factors, especially climate and soils. This paucity of data reduces the ability of farmers to develop effective strategies to cope and adapt to the negative effects of climate variability and change. The aim of this study was to investigate the seasonal changes in the energy and water balance of rooibos fields and to establish how this relates to crop yield. An open path eddy covariance system was used to quantify the actual evapotranspiration (ETa) and energy balance components over two growing seasons while sap flow was monitored using stem heat balance sap flow gauges. These data were used to develop and test a simple ETa and yield model which was applied to estimate changes in crop water use and yield under the predicted future climatic conditions. More than 36% of the annual total ETa (∼ 338 mm) was consumed during the first three months of the growing season (September to November) driven by residual soil moisture from the winter rains. Crop transpiration accounted for only 16% of ETa early in the growing season rising to almost 100% during the summer dry months. Daily peak transpiration at maximum canopy cover barely reached 1.0 mm suggesting that this crop uses very little water. Six climate change models were used to simulate crop water use and yield for the far future under the RCP 8.5 emission scenario. All the models predicted increases in both the annual ETa and yield by between 8% and 16% in the period 1961–2099. This study reveals that implementing water conservation and weed management practices early in the growing season can save substantial amounts of soil moisture which can sustain rooibos production under low rainfall conditions.

Effects of land use change on ecosystem services in the China–Mongolia–Russia economic corridor

Understanding the spatiotemporal characteristics of land use, ecosystem services, and their relationship provides a basis for the sustainable development of ecosystems. However, the effect of land use change on multiple ecosystem services has not been widely quantified, especially in transnational areas. This study analysed the spatiotemporal characteristics of land use change in the China–Mongolia–Russia Economic Corridor using the ESA-Global Land Cover product from 1992 to 2019. We used the InVEST model to evaluate the changes in carbon storage, habitat quality, water yield, and soil retention and quantified the contribution of land use to the changes in ecosystem services by calculating the ecosystem service contribution index (ESCI). The results showed that from 1992 to 2019, the urban/built-up environment and croplands increased by 22,010 km 2 and 32,946 km 2 , respectively, which led to the continuous decline of forests. The implementation of ecological projects significantly decreased the barren environment. The value of four ecosystem services gradually decreased depending on the distance from the coastline and improved overall from 1992 to 2019. Land use conversion significantly affected ecosystem services. The expansion of croplands, urbanisation, and desertification had a significant negative impact on ecosystem services and the conversion to grasslands. Forests had a significant positive impact on ecosystem services. The findings will enrich our understanding of ecosystem services in transnational areas and help balance the relationship between ecological conservation and social-economic development in the China-Mongolia-Russia Economic Corridor. • Land-use change had significant spatiotemporal differences from 1992 to 2019. • Quantitative assessment to the contributions of land use conversion on changes in ecosystem services. • Ecosystem services improved in the China–Mongolia–Russia Economic Corridor. • Land-use conversion was significantly correlated with ecosystem services.

Changes of water yield in Tumen River Basin, China: trade-offs between precipitation and actual evapotranspiration

Changes of water yield in Tumen River Basin, China: trade-offs between precipitation and actual evapotranspiration

Generalized Additive Model Reveals Nonlinear Trade-Offs/Synergies between Relationships of Ecosystem Services for Mountainous Areas of Southwest China

Ecosystem services (ESs) are an essential link between ecosystems and human well-being, and trade-offs/synergies happen in ESs at different temporal and spatial scales. It is crucial to explore patterns of trade-offs/synergies among ESs, and their nonlinear relationships with changes in ESs. The primary objective of this study was to evaluate five ESs in 2000 and 2018: namely, water yield, food production, carbon sequestration, soil conservation, and habitat quality in mountainous regions of Southwest China. The mean values of the five ESs increased by 365.8 m3/ha, 13.92 t/hm2, 497.09 TgC/yr2, 138.48 t/km2, and 0.002, respectively. Using spatial statistics and analysis, an ES trade-off synergy model (ESTD) was constructed for the five ESs change values. Overall, soil conservation has a trade-off with all five ESs, except habitat quality; this trade-off is increasing slightly. Water yield is in synergy with all ESs except soil conservation, with decreasing synergy; habitat quality is in synergy with all ESs except food production, with increasing synergy. Finally, the nonlinear relationship between the value of the change in the ES and ESTD was analyzed using a generalized additive model. Changes in water yield showed the greatest impact on ESTD except for food production, wherein changes in all three ESs had minimal impacts on ESTD. Food production dominates its trade-offs/synergies relationship with soil conservation; carbon sequestration is the dominant player in its trade-offs/synergies relationship with soil conservation. Habitat quality has a secondary position of influence, except in the trade-offs/synergies involving food production. By exploring the drivers of trade-offs/synergies among ESs, this study can provide guidance for the effective implementation of policies related to ecological protection and restoration.

Predicted Rainfall, Surface Runoff and Water Yield Responses to Climate Change in the Phetchaburi River Basin, Thailand

Expected changes in temperature, rainfall, water yield and surface runoff dynamics under RCP 8.5 were estimated in the Phetchaburi River Basin, Thailand, using outputs of five regional climate models. Observed temperatures and precipitations were downscaled using a combination of quantile mapping and nearest neighbour methods. The SWAT model was used to estimate changes in hydroclimatic variables in both the near-term (2006-2050) and long-term (2051-2099) temporal frames. All models predicted higher temperatures in the future (28.7-30.4°C) compared to the historical situation (28.0-28.3°C). The patterns of maximum temperature from most models were shifted one month earlier but there was no significant change for minimum temperature. Disagreement between models could be found in projected precipitations for the short term, but most of them pointed to an increase in rainfall in the long term, especially for maximum rainfalls ranging from 1,637 to 1,947 mm. CNRM-CM5 presented large differences in the future rainfalls compared to other models. Surface runoff/water yield significantly increased by 14%/17% in the long-term following the same trend as rainfalls with a slight change in the short-term.

Combined effects of multi-land use decisions and climate change on water-related ecosystem services in Northeast China

Land use intensification and climate change have resulted in substantial changes in the provision of ecosystem services, particularly in China that experienced sharp increases in population growth and demands for goods and energy. To protect the environment and restore the degraded ecosystems, the Chinese government has implemented multiple national ecological restoration projects. Yet, the combined effects of climate change and land use and land cover change (LULCC) over large spatial scales that brace multiple land use decisions and great environmental heterogeneity remain unclear. We assessed the combined effects of LULCC and climate change on water-related ecosystem services (water provision and soil conservation services) from 1990s to 2020s in Northeast China using the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model. We found that water yield decreased by 9.78% and soil retention increased by 30.51% over the past 30 years. LULCC and climate change exerted negative effects on water yield whereas they both enhanced soil retention; LULCC interacted with climate change to have relatively small inhibitory effects on water yield and large facilitation effects on soil retention. Changes in water yield were mainly attributed to climate change, while soil retention was largely influenced by LULCC and its interaction with climate change. Our research highlights the importance of land use decisions and its interactive effects with climate change on ecosystem services in a heavily disturbed temperate region, and provides important information to inform future land management and policy making for sustaining diverse ecosystem services and ensuring human wellbeing.

Spatial heterogeneity of ecosystem services in response to landscape patterns under the Grain for Green Program: A case‐study in Kaihua County, China

AbstractUnderstanding the impact of landscape patterns on ecosystem services (ES) is crucial for the design and management of ecological restoration programs. However, the impacts of landscape configuration on ES from a geospatial perspective have not been studied sufficiently. This study analyzed the landscape composition and pattern changes and quantified the changes in water yield, carbon storage, soil retention, water purification, and habitat quality under the Grain for Green Program (GFGP) from 2000 to 2020 in Kaihua County. The responses of ES to landscape patterns were revealed by geographic detector and geographically weighted regression models. The results showed that landscape fragmentation and diversity increased, and forest landscape area and aggregation increased because of the GFGP implementation. Water yield declined with the decrease in the mean patch area of the landscape, while other ES improved due to the increase in Shannon's diversity index and largest patch index. The interspersion and juxtaposition of cropland and forest land played an important role in improving ES under the GFGP. In addition, some ES may be closely related to natural factors and connection to landscape patterns, such as soil retention and topography, water yield and precipitation, but this response to landscape pattern changes was captured due to the subjective nature of the GFGP. The results can provide scientific guidance for forest landscape restoration to better improve ES.

Analysis of Water Yield Changes from 1981 to 2018 Using an Improved Mann-Kendall Test

Water yield (WY) refers to the difference between precipitation and evapotranspiration (ET), which is vital for available terrestrial water. Climate change has led to significant changes in precipitation and evapotranspiration on a global scale, which will affect the global WY. Nevertheless, how terrestrial WY has changed during the past few decades and which factors dominated the WY changes are not fully understood. In this study, based on climate reanalysis and remote sensing data, the spatial and temporal patterns of terrestrial WY were revisited from 1981 to 2018 globally using an improved Mann-Kendall trend test method with a permutation test. The response patterns of WY to precipitation and ET are also investigated. The results show that the global multi-year mean WY is 297.4 mm/a. Based on the traditional Mann-Kendall trend test, terrestrial WY showed a significant (p < 0.05) increase of 5.72% of the total valid grid cells, while it showed a significant decrease of 7.68% of those. After correction using the calibration method, the significantly increasing and decreasing areas are reduced by 10.52% and 10.58% of them, respectively. After the correction, the confirmed increase and decrease in WY are mainly located in Africa, eastern North America and Siberia, and parts of Asia and Oceania, respectively. The dominant factor for increasing WY is precipitation, while that for decreasing WY was the combined effect of precipitation and evapotranspiration. The achievements of this study are beneficial for improving the understanding of WY in response to hydrological variables in the context of climate change.

Understanding the accuracy of modelled changes in freshwater provision over time

Accurate modelling of changes in freshwater supplies is critical in an era of increasing human demand, and changes in land use and climate. However, there are concerns that current landscape-scale models do not sufficiently capture catchment-level changes, whilst large-scale comparisons of empirical and simulated water yield changes are lacking. Here we modelled annual water yield in two time periods (1: 1985–1994 and 2: 2008–2017) across 81 catchments in England and validated against empirical data. Our objectives were to i) investigate whether modelling absolute or relative change in water yield is more accurate and ii) determine which predictors have the greatest impact on model accuracy. We used the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) Annual Water Yield model. In this study, absolute values refer to volumetric units of million cubic metres per year (Mm3/y), either at the catchment or hectare level.Modelled annual yields showed high accuracy as indicated by the low Mean Absolute Deviation (MAD, based on normalised data, 0 is high and 1 is low accuracy) at the catchment (1: 0.013 ± 0.019, 2: 0.012 ± 0.020) and hectare scales (1: 0.03 ± 0.030, 2: 0.030 ± 0.025). But accuracy of modelled absolute change in water yield showed a more moderate fit on both the catchment (MAD = 0.055 ± 0.065) and hectare (MAD = 0.105 ± 0.089) scales. Relative change had lower accuracy (MAD = 0.189 ± 0.135). Anthropogenic modifications to the hydrological system, including water abstraction contributed significantly to the inaccuracy of change values at the catchment and hectare scales.Quantification of changes in freshwater provision can be more accurately articulated using absolute values rather than using relative values. Absolute values can provide clearer guidance for mitigation measures related to human consumption. Accuracy of modelled change is related to different aspects of human consumption, suggesting anthropogenic impacts are critically important to consider when modelling water yield.

Impacts of Future Climate and Land Use/Cover Changes on Water-Related Ecosystem Services in Changbai Mountains, Northeast China

Sustaining ecosystem services in alpine regions is a pressing global challenge given future accelerating environmental changes. Understanding how future climate change and land use/cover change (LUCC) drive ecosystem service will be important in this challenge. However, few studies have considered the combined effects of future climate change and LUCC on ecosystem services. We assessed water yield and soil retention services and their drivers in the Changbai mountains region (CBMR) from the 2020 to 2050s using the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model and factor control experiments. Water yield decreased by 2.80% and soil retention increased by 6.14% over the 30 years. Climate change decreased water yield and increased soil retention, while LUCC decreased both water yield and soil retention. The interactive effects between climate change and LUCC had relatively small inhibitory effects on water yield and large facilitation effects on soil retention. Changes in water yield were mainly attributed to climate change, while soil retention was largely influenced by interaction. Our study highlights the individual and interactive contributions of future climate change and land use to ecosystem service in the mountains region, which can provide important information for informed future land management and policy making for sustaining diverse ecosystem services.

Assessing impacts of the Ecological Retreat project on water conservation in the Yellow River Basin

The Ecological Retreat (ER) project significantly impacts water conservation functions in the Yellow River Basin (YRB). However, studies on the impact and benefit of different ER modes on ecological water effects still lack systematic and integral disclosure. In our study, CNLUCC (China land use/cover data sets) and the Markov transition matrix were used to simulate land pattern changes from 2000 to 2018. Water yield was chosen as an indicator of water conservation to explore the impact of the ER project by using the water yield module of the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model. After the ER project, the land pattern changed significantly because massive cropland was transformed into forest and grassland. Thus, the total water yields of the YRB increased by 46.32 × 103 hm3 from 2000 to 2018, and the overall water yield benefit was 12.39% larger than the water loss. Forest rehabilitation (FR) showed the highest average water yield capacity, while grassland restoration (GR) exhibited the most incredible total water conservation benefit. Wetland recovery (WLR) manifested a great capacity to improve average water yield, but its total benefit was far less than FR and GR, while waterbody recovery (WBR) showed a negative impact. The results indicate that FR and GR were effective restoration methods, and WLR showed great potential to improve water yield. By using the random forest and principal components analysis, precipitation (PRE), evaporation (AET and ET0), and variation of forest and grassland proved to be the most critical driving indicators affecting water yield changes. Additionally, the correlation and sensitivity between root depth (R_depth) and water yield indicate that increasing R_Depth can also enhance water conservation. The ER project provides a valuable restoration model for water yield and water conservation benefits. The results can provide theoretical support for eco-hydrology and land ecological restoration studies.

Changes of Soil Water and Heat Transport and Yield of Tomato (Solanum lycopersicum) in Greenhouses with Micro-Sprinkler Irrigation under Plastic Film

This study aimed to expound the changes in soil water flow, heat transport, and tomato production under micro-sprinkler irrigation and plastic film (MSPF) conditions. The effects of different irrigation amounts (I1:0.7 Epan; I2:1.0 Epan; and I3:1.2 Epan (Epan is the cumulative evaporation from a 20 cm diameter standard pan, mm)) on soil water, soil temperature, and tomato yield were studied. A completely randomized trial design was used; meanwhile, the drip irrigation under plastic film (CK1) and micro-sprinkler irrigation without mulch film (CK2) were used as controls. The results showed that the shape of soil moisture was banded under MSPF; the soil wetting range was larger than that of CK1 and CK2 in the profile of MSPF. The change range of 5 cm soil temperature of MSPF 1–5 days after irrigation was 4.05 °C. The change range of 5 cm soil temperature of MSPF was lower than that of CK1 from 1 to 5 days after irrigation. During the growth period of spring and autumn tomato, the average soil moisture content of 0–40 cm with CK1 was 1.97% and 3.83% (spring and autumn, respectively) higher than that of MSPF, and the average soil temperature of 5–25 cm was 2.36% and 1.66% (spring and autumn, respectively) lower than that of MSPF. Compared with CK2, the average soil moisture content of 0–40 cm under MSPF increased by 8.30% and 3.83% (spring and autumn, respectively), and the average soil temperature of 5–25 cm under MSPF increased by 5.85% and 1.68% (spring and autumn, respectively). The spring and autumn tomato yield of MSPF was significantly higher than that of CK1 by 19.39% and 4.54%, respectively. The spring and autumn tomato yield of MSPF were higher than that of CK2 by about 20.46% and 49.22%, respectively. With an increase in the irrigation amount of MSPF, the soil moisture and yield of spring and autumn tomato increase; the soil temperature and water use efficiency of spring and autumn tomato decrease. Considered comprehensively, the MSPF can be used as one of the methods of greenhouse tomato micro-irrigation, and 1.0 Epan is recommended for irrigation parameters in northwest China facility agriculture.

The Trade-Offs and Synergies of Ecosystem Services in Jiulianshan National Nature Reserve in Jiangxi Province, China

Ecosystem services are directly related to human well-being. Previous studies showed that management policies and human activities alter the trade-offs and synergies of ecosystem services. Taking effective measures to manage the trade-offs and synergies of ecosystem services is essential to sustain ecological security and achieve a “win-win” situation between society and ecosystems. This study investigated the spatiotemporal changes of water yield, soil conservation, and carbon sequestration in the Jiulianshan National Nature Reserve from 2000 to 2020 based on the InVEST model. We distinguished spatial patterns of trade-offs and synergies between ecosystem services using the correlation relationship analysis. Then we analyzed the response of ecosystem services relationships among different vegetation types and elevation bands. The results showed that water yield and carbon sequestration presented an overall upward trend, while soil conservation remained a marginal degradation. Rising ecosystem services were mainly in the central, western, and southeastern regions, and declining areas were mainly distributed in the midwestern and northeastern fringes. Synergies spatially dominated the interactions among water yield, soil conservation, and carbon sequestration, and the trade-offs were primarily concentrated in the northern, southern, and southwestern fringes. Among the different vegetation types, synergies dominated ecosystem services in broad-leaved forests, coniferous forests, mixed forests, and Moso bamboo forests and in grass. The trade-offs were gradually reduced with elevation. This study highlighted that trade-off of ecosystem services should be incorporated into ecological management policies, strengthening the effectiveness of nature reserves in protecting and improving China’s ecosystem services.