Increase In Water Yield Research Articles

Thinning Impacts on Carbon and Water Budgets in a Temperate Deciduous Forest Ecosystem

Among various forest management activities, thinning is a prevalent treatment that affects tree growth and living biomass. Increased moisture and light availability may also enhance the mineralization of litter and dead wood organic matter, impacting soil carbon stocks. Thinning may also affect the services forests provide, including water production and nutrient cycling. The impacts of thinning on water yield and carbon stocks have been well documented around the globe while targeting mainly one of these ecosystem services. Our experimental paired catchment study covers both and puts forward long term results. We assessed the carbon stock changes caused by two slight thinning treatments together with the impacts on water yield in experimental paired catchments of 71.9 (W–I) and 77.5 hectares (W–IV) in Istanbul, Türkiye. The null hypothesis was that the slight thinnings did not affect the water yield and carbon stocks significantly. On the carbon stock part, we calibrated and parametrized the CBM–CF3 model with field measurements to simulate changes in carbon stocks of mixed deciduous forest stands. The intensities of the treatments (thinnings) were 11% and 18% of the basal area, performed in 1986 and 2011, respectively. We found that, while C stocks decreased by around 30 tons per hectare during the 1986–2020 period, the water yield was enhanced by approximately 25 mm/yr in the treatment catchment compared to the control watershed during the four-year post-treatment period. This amount of streamflow increase was around 10 percent of the average water yield of the catchments. It was concluded that there was a detectable increase in water yield during the following four years of the slight thinning treatments, while the reduction in abovegound carbon stocks continued for more than three decades.

Effects of Climate Change and Changes in Land Use and Cover on Water Yield in an Equatorial Andean Basin

Ecosystem services contribute significantly to human development, with water production being a crucial component. Climate and land use changes can impact water availability within a basin. In this context, researching water-related areas is essential for formulating policies to protect and manage hydrological services. The objective of this study was to estimate water yield in the sub-basins of the Tabacay and Aguilán rivers under climate change scenarios in 2030, 2040, and 2050, combined with scenarios of changes in land cover and land use. The InVEST model was employed to analyze water yield. The results show that crop areas were identified as the lowest water yield in future scenarios, and forested areas, particularly the region where the Cubilán Protected Forest is located, contribute the most to water yield in the subbasin. Besides, water yield has increased in the historic period (2016–2018) due to the conservation and reforestation initiatives carried out by the Municipal Public Service Company for Drinking Water, Sewerage, and Environmental Sanitation of the city of Azogues in 2018, the so-called Reciprocal Agreements for Water. Additionally, an increase in water yield is projected for future scenarios. This study can serve as a basis for decision-makers to identify areas that should prioritize protection and conservation.

Global analysis of forest tipping points leading to changing water cycle dynamics

Forest cover loss is increasing at unprecedented rates, affecting the hydrologic systems of major freshwater-producing regions of the world. However, quantification of the tipping points of forest cover loss before hydrologic changes manifest and their impact in water yield and climatic conditions has remained elusive. In this study, we aim to systematically document the critical thresholds of tree cover loss leading to changing hydrologic functioning within regions that experienced extensive drought, fire, or clear-cutting events spanning different climates during the period from 2001 to 2016. Using the Hydrologic Sensitivity Index based on Budyko’s curve, we analyzed the changes in hydrologic responses to climate variability as landcover changes across the affected forests. Critical thresholds were derived by fitting Richard’s Curve function to the observed relationship between growing sensitive area and tree cover loss. Our analysis reveals decrease in water yields and warming trends during the early stages of tree cover loss in tropical forests (c = 16 %), with negative anomalies observed in rainforests of Central Africa and Maritime Southeast Asia. Boreal forests also show low thresholds (c = 18 %) with a strong tendency toward a warmer climate state and no clear tendency in water yields. Mixed forests show moderate thresholds (c = 25 %) with unclear water yield and climate trends. Conversely, Temperate forests exhibit the most resilience to hydrologic regime shifts with high critical thresholds of tree cover loss (c = 46––54 %), but a rapid alteration once their threshold is surpassed resulting primarily in increased water yields and a shift toward cooler climate conditions. As the potential for additional tree cover loss heightens, due to expected increases in the frequency and intensity of droughts and wildfires, the analyses presented provides a quantitative framework to monitor and assess the impacts of changing forest cover conditions on the water cycle behavior of some of the largest freshwater producing regions of the world.

Changes in snow‐dominated streamflow quantity and timing following an extensive wildfire in British Columbia

AbstractThe length and frequency of extreme fire weather has increased across the globe in recent decades, with potential deleterious consequences to streamflow quantity, timing and quality. Changes in the hydrologic regime following wildfire can have substantial downstream consequences, affecting communities and ecosystems through flooding, erosion, loss of habitat and degraded water quality. While there are many studies that address post‐wildfire hydrology across the globe, there are few studies in the snow‐dominated regions. The 2017 Elephant Hill wildfire in south‐central BC burned across or adjacent to four watersheds with long‐term streamflow gauges providing a rare opportunity to evaluate hydrologic change. Several approaches were used to identify patterns of change following the wildfire, all of which suggest increased post‐fire flows. The before‐after‐control‐impact design showed significant increases in annual, spring and summer water yield from the small (49 km2) Arrowstone Creek watershed (30%, 21% and 86%, respectively). Significant increases in spring water yield were observed in the larger (5318 km2) Bonaparte River watershed (48%). Annual and summer water yield increased in the Bonaparte River (31% and 58%, respectively) but these changes were not statistically significant. In both the Bonaparte River and Arrowstone Creek, the onset of spring freshet (26 days earlier in both) was significantly advanced, however, the timing of maximum snowmelt discharge was significantly advanced (27 days earlier) only in Arrowstone Creek. Smaller changes were also observed in the reference watersheds; however, these were not statistically significant. The difference in results between the small and large watershed, as well as the effects of weather and watershed attributes, highlight the need for continued research into the relationships between wildfire and hydrologic regime across diverse landscapes.

Rice yield and water productivity in response to water-saving irrigation practices in China: A meta-analysis

Various water-saving irrigation (WSI) practices (e.g., dry cultivation, intermittent irrigation, controlled irrigation, shallow-wet irrigation, and rain-gathering irrigation) have been applied to rice cultivation mitigate water scarcity in China. However, in previous studies, these WSI practices have shown different water savings and yield increases, mainly due to different application conditions. A meta-analysis was applied to investigate the responses of the actual evapotranspiration (ETact), irrigation water (IW), rice yield (Y), and water productivity (WP) to WSI practices in different conditions, and 956 data sets were selected from 108 published papers. The results showed that, compared to traditional flood irrigation, rain-gathering irrigation decreased ETact and IW by 25.41 % and 55.7 % respectively, and increased WP greatly by 14.26 % while having a slight decrease in Y. Except for dry cultivation, all WSI practices increased WP by 4.72–14.26 % compared to traditional flood irrigation. The effects of different soil qualities on rice water consumption and production vary; medium soils with high organic content and a pH below 6.5 are better for rice growth. As for rice seasons, WSI practices had the least impact on ETact in middle rice, with an average reduction of 5.84 %, followed by early rice (–12.66 %) and late rice (–18.81 %). Higher mean annual temperature and more precipitation led to more Y under WSI practices. Differences in the effects of mean annual temperature and mean annual precipitation on WP were not significant. Our meta-analysis provides more insight into the effects of water-saving irrigation practices on rice water consumption, yield, and water productivity at various experimental sites. In general, there is considerable variation in the responses of Y and WP to different water-saving irrigation practices, and more evaluation of aspects such as rice seasons, soil properties, and meteorological conditions is needed for optimizing WSI in practice.

Impact of Land use dynamics on the water yields in the Gorgan river basin

This research investigates the future dynamics of water yield services in the Gorgan River Basin in the North of Iran by analyzing land cover changes from 1990 to 2020, using Landsat images and predicting up to 2040 with the Land Change Modeler and InVEST model under three scenarios: continuation, conservation, and mitigation. The results indicate significant shifts in agricultural land impacted water yields, which fluctuated from 324.7 million cubic meters (MCM) in 1990 to 279.7 MCM in 2010, before rising to 320.1 MCM by 2020. The study uniquely assesses the effects of land use changes on water yields, projecting a 13.6 % increase in water yield by 2040 under the continuation scenario, a 3.9 % increase under conservation, and a 1.6 % decrease under mitigation, which limits changes on steep slopes to prevent soil erosion and floods. This underscores the interplay between land use, vegetation cover, and water yield, emphasizing strategic land management for water resource preservation and effective watershed management in the GRB.

Forest management for water yield: Assessing the barriers and impacts of privately-owned open pine woodlands in the Southeastern United States

In the Southeastern United States, freshwater resources are stressed due to human development, population growth, expansion of agricultural irrigation, and climate change. Restoring land to a low-density, fire-maintained longleaf pine (Pinus palustris) savanna and woodland ecosystem may provide distinct ecosystem services such as increases in water quantity for vulnerable watersheds. To understand how economic incentives may bolster restoration programs, we analyze the economic and hydrologic impacts of longleaf pine restoration scenarios. We compare these scenarios against other common land uses in the Coastal Plain of Georgia, a major forestry state located in the Southern United States, identifying the financial barriers and water use impacts of alternative forest management regimes. Longleaf pine restoration shows the greatest increase in water yield per acre at 66 % over baseline timber production scenarios but at a lower timber value return. Thinning planted loblolly pine (Pinus taeda) stands to low-density woodlands may offer a more cost-efficient, immediate alternative that improves water yields by 38 %. Current incentives to restore native habitats on private lands increase financial returns but lack sufficient incentives and governance to meet or exceed baseline forest income levels by $90-$235 ha-1 annually for longleaf savanna restoration. In the future, the emerging ecosystem service market in Georgia may steer decisions about competing values of carbon storage, water yield, and native habitat restoration.

Water yield response to forest treatment patterns in a sierra nevada watershed

Study regionSierra Nevada Study focusSnow dominated forests serve as source water supplies to much of the western United States. In recent years, these forests have experienced an increase in both drought and wildfire, which threaten critical water resources. By reducing forest density, treatments offer a promising solution to reducing fuel loads and potentially increasing surface water yield. However, the amount of fuel load reduction necessary to produce a change in water yield is not well-characterized. The objectives of the current study are to: 1) calibrate a distributed parameter, fully-integrated and physically-based hydrologic model to available watershed data and evaluate predicted hydrologic changes for a range of fuel treatment scenarios in a heavily forested experimental basin in the Sierra Nevada (Sagehen Creek basin near Truckee, California, USA), and 2) determine the extent (threshold) of forest treatments necessary to produce substantial changes, i.e. a 25% increase, in surface runoff. New hydrological insights for the regionUsing DHI’s physically-distributed code, MIKESHE, to develop the model for Sagehen Basin, twenty forest treatment scenarios with varying canopy density reductions (CDRs) and areas of treatment were simulated for a five-year period. Statistical testing showed that significant change in runoff occurred for every developed scenario at the annual scale (99% confidence interval). Surface water yield is highly correlated with precipitation patterns, however, treatments have a compounding effect over the years and the basin has a more dramatic response to higher treatment intensities. Increasing treatment CDR was more effective at increasing water yield than increasing treatment area. Results suggest that as forest managers implement fuel treatments, water yield response depends on: 1) the degree to which treatments are implemented by either area or CDR, 2) future climate variability including extended periods of drought, and 3) basin storage conditions and how this might buffer disturbance response in the basin.

Assessment of Ecosystem Services and Exploration of Trade-Offs and Synergistic Relationships in Arid Areas: A Case Study of the Kriya River Basin in Xinjiang, China

This research focuses on the Kriya River Basin and analyzes the spatiotemporal variability of ecosystem services (ESs) and their trade-offs and synergies, which are vital for regional ecosystem conservation and socio-economic sustainability. Utilizing land use data from 1990 to 2020 and predictive models for 2030 (PLUS for land use and InVEST for ESs), the study assesses four key ESs: water yield (WY), soil conservation (SC), habitat quality (HQ), and carbon storage (CS). The findings indicate that land use changes from 1990 to 2020 have significantly impacted these services. WY showed a negative trend because of a reduction in precipitation, while increased grasslands enhanced SC, HQ, and CS. Projections for 2030 suggest increases in WY and SC, with increases of 10.27 × 108 m3 in WY and 0.216 × 108 t in SC, but slight decreases in HQ and CS due to urban land expansion. Therefore, land types that provide important ESs should be protected in future planning, and the expansion of construction land should be controlled in order to realize the goal of ecological conservation. Our study also reveals that while WY and CS share a subtle trade-off, they both synergize with SC and HQ. Strong synergies exist between SC and HQ as well as between SC and CS, indicating lesser concerns for trade-offs in future planning. This research provides valuable data support and scientific insight for sustainable development and ecological governance policies in the watershed.

Evolution of ecosystem services under the impact of urbanization using the InVEST model in the xiongan new area, China

Abstract Understanding the impact of land use on ecosystem service functions is crucial for guiding land management and ecological environment protection in Xiongan New Area (XANA), China. This paper employs the InVEST model to assess the temporal and spatial characteristics of water yield, carbon storage, water purification, and soil conservation ecosystem services in XANA from 1980 to 2020, analyzing geographical and spatial variations in ecosystem service capabilities. Through correlation analysis and the grid Moran’s I index, we explored the mechanisms of ecosystem action and the trade-offs and synergies among these services. Our results revealed that urban land use in XANA increased throughout the 1980–2020 period, with the fastest growth occurring from 2010 to 2020, primarily due to cultivated land conversion. Prior to 2010, cultivated land expanded rapidly, consuming significant amounts of water resources. Changes in land use structure drove increases in water yield and nitrogen output in the XANA ecosystem while decreasing carbon storage and soil erosion. Urban land area change was the primary factor influencing water yield and nitrogen output, while reduced water area was the main driver behind decreased carbon storage in the region. Cultivated land was identified as the primary contributor to soil erosion. The synergy between carbon storage and water conservation is closely tied to water area and urban land, while the synergies between carbon storage and water quality purification, soil conservation and water quality purification hinge on water areas and cultivated land areas. To ensure the sustainable development of XANA, it is essential to protect the wetland ecosystem in the Baiyangdian Lake basin, enhance forest and grassland coverage, and monitor temporal and spatial changes in different ecosystem services and their interrelationships closely.

Assessment of Hydrological Responses to Land Use and Land Cover Changes in Forest-Dominated Watershed Using SWAT Model

Recognizing how human activities affect hydrological systems is vital for the sustainable preservation and effective management of water resources in the watershed. Hence, this paper focuses on the hydrological response to land use and land cover (LULC) change scenarios in the Anyang watershed, South Korea. We obtained LULC data maps for the years 2000, 2013, and 2022 from the local government, revealing significant changes over the years. Agricultural lands experienced a 6.2% increase from 2000 to 2022, and pastureland expanded by 8.67% over two decades. The SWAT model was utilized to assess the impact of LULC on the hydrological components of the study watershed. Model calibration and validation for each LULC change were carried out using the SWAT-CUP program, considering the recorded streamflow information of the region. An excellent agreement was reached between the simulated and measured streamflow in both the calibration and validation stages under various LULC conditions. The Nash–Sutcliffe model efficiency (NSE), the objective function, demonstrated values of 0.9, 0.89, and 0.89 during the calibration for 2000, 2013, and 2022, respectively, in the LULC scenario, while for the validation, we obtained values of 0.82, 0.78, and 0.80 for 2000, 2013, and 2022, respectively. Our findings indicate that the surface runoff rise contributed much to the water yield increase over the two decades compared to the other components in terms of the water yield, while the contribution of evapotranspiration (ET) to the watershed hydrological cycle declined by 1.66% from 2000 to 2022. The southeastern sub-basin part showed a high groundwater recharge distribution due to agricultural land, rice area, and forest area changes.

Impacts of multi-scenario land use change on ecosystem services and ecological security pattern: A case study of the Yellow River Delta

The Yellow River Delta (YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the region has witnessed significant land use/cover changes (LUCC), impacting ecosystem services (ES) and ecological security patterns (ESP). Investigating LUCC's effects on ES and ESP in the YRD is crucial for ecological security and sustainable development. This study utilized the PLUS model to simulate 2030 land use scenarios, including natural development (NDS), economic development (EDS), and ecological protection scenarios (EPS). Subsequently, the InVEST model and circuit theory were applied to assess ES and ESP under varying LUCC scenarios from 2010 to 2030. Findings indicate: (1) Notable LUCC from 2010 to 2030, marked by decreasing cropland and increasing construction land and water bodies. (2) From 2010 to 2020, improvements were observed in carbon storage, water yield, soil retention, and habitat quality, whereas 2020–2030 saw increases in water yield and soil retention but declines in habitat quality and carbon storage. Among the scenarios, EPS showed superior performance in all four ES. (3) Between 2010 and 2030, ecological sources, corridors, and pinchpoints expanded, displaying significant spatial heterogeneity. The EPS scenario yielded the most substantial increases in ecological sources, corridors, and pinchpoints, totaling 582.89 km2, 645.03 km2, and 64.43 km2, respectively. This study highlights the importance of EPS, offering insightful scientific guidance for the YRD's sustainable development.

Effect of biochar addition on water–salt distribution and growth of winter wheat in coastal saline‐alkali soils under brackish water irrigation

AbstractTo investigate water‐saving and yield‐enhancing improvement programmes suitable for saline‐alkali soils in the Yellow River Delta region, this study conducted outdoor pot experiments utilizing local moderately saline‐alkali soils as research subjects. The primary focus was to examine the impact of biochar addition on water and salt distribution in saline‐alkali soils and its effect on winter wheat growth under brackish water irrigation conditions. The study design established three different irrigation water mineral concentrations (0, 2 and 4 g L−1) during the research. Two types of biochar, wheat straw biochar (WB) and corn straw biochar (CB), were used with four different applications (0, 5, 10 and 20 t ha−1). There were 21 treatments; each replicated three times. These findings demonstrated that brackish water irrigation and biochar application contributed to a notable increase in soil water content (SWC), with increases ranging from 12.8 to 83.9% across treatments. Using brackish water for irrigation increases soil salt content (SSC) and exacerbates soil salinization. However, the application of biochar counteracts this effect by reducing soil salinity and mitigating the degree of salinization. Treatments applying biochar mostly increased SSC, but proper application had a salinity‐reducing effect, reducing SSC by up to 15.2%. And biochar reduced the soil sodium adsorption ratio (SAR) and exchangeable sodium percentage (ESP), mitigating the adverse effects of high salinity on winter wheat. Finally, the application of biochar promoted the growth of winter wheat and increased yield, with the treatment applying 10 t ha−1 of CB (K2Y10) producing the greatest yield under brackish water irrigation conditions and increased by 18% compared with the treatment without biochar (CK0). In summary, considering the aspects of water conservation, salt reduction and yield increase, the most effective saline land improvement programme for this region involved using 2 g L−1 brackish water for irrigation in combination with applying K2Y10. This approach balances addressing soil salinity, enhancing water conservation and maximizing crop yields.

Study of the effects of land use change on water yield in the Qilian Mountains in western China

The Qilian Mountains serve as significant ecological security barriers in the western region of China. Their continuous and stable water supply is essential for the sustainability of the human oasis in the Hexi Corridor, as well as for the maintenance of the desert ecosystem in the north. In the past three decades, land use in this area has changed significantly because of human activities, which has had a profound impact on water yield services. Based on the Water Yield module of the InVEST model, we evaluated the area and water yield of land use during 1990–––2020, and discussed the characteristics of water yield response to changes in land use. As a result of the study, it was found that in the Qilian Mountains during the period 1990–––2020: (1) the areas of swamp, unused land, medium coverage grassland, and woodland reduced, while the areas of high coverage grassland, low coverage grassland, cultivated land, construction land, glaciers, and water area increased, and each land use type exhibited a different degree of transformation. (2) In terms of total water yield, this declined by 1.09 × 108 m3, water yield of medium coverage grasslands, unused land, and swamp decreased, while water yield of other land uses increased, however, the responses to the change in water yield as a result of the change in land use were significant. (3) The areas with decreased water yield fall mainly within the high-altitude areas of the Qinghai Lake and Qaidam river watersheds, while the low-altitude areas were characterized by an increase in water yield. This study may provide decision-makers with guidance for protecting the ecosystem of the Qilian Mountains and developing a national park in the Qilian Mountains.

Response of water yield to silvicultural treatments in a temperate forest in northern Mexico

Forest management modifies tree cover, directly influencing various ecosystem services, such as water regulation. Evapotranspiration, water interception, surface runoff, stemflow, and throughfall are among those processes that depend on tree cover. The objective of this study was to evaluate the changes in water yield, defined as the difference between precipitation and evapotranspiration, after the application of silvicultural treatments in a temperate forest ecosystem in northern Mexico. Fifteen experimental plots were established in which the following treatments were applied: intensive management (clearcutting), semi-intensive management (selection, tree cutting of 59–61% of basal area), conservative management (selection, tree cutting of 29–31% of basal area), and no treatment (control group). Incident precipitation, throughfall, stemflow, net precipitation, interception, and surface runoff were analyzed. Results show that conservative management treatments increase water yield between 2 to 3.6 mm per m-2 ha-1 of tree basal area removed. Water flow distribution, in relation to the incident precipitation, ranged from 72.3 to 91.8% for throughfall, 0.2 to 0.4% for stemflow, 72.7 to 91.8% for net precipitation, 8.19 to 27.42% for interception or evaporation, and 0.54 to 1.93% for surface runoff. The conservative management treatment was the most viable alternative for increasing water yield without compromising timber harvesting and loss of soil due to hydric erosion.

Influence of human-induced land use change on hydrological processes in semi-humid and semi-arid region: A case in the Fenhe River Basin

Study Region: The Fenhe River Basin (FRB) is an important tributary of the Yellow River Basin and locate in a semi-arid and semi-humid region in northwest China. Over the past four decades, significant anthropogenic activities have resulted in significant land use and land cover change (LUCC) that have markedly impacted hydrological processes in FRB.Study Focus: To analyze land use changes under multiple historical land use scenarios from LU1980 to LU2015, and to establish the Water and Energy transfer Processes in Large basins (WEP-L) model to quantify the influences of LUCC on hydrological processes, particularly on baseflow.New hydrological insights for the region: LUCC from LU1980 to LU2015 resulted in a 14.5 % increase in water yield (WY) and a 2.7 % and 1.4 % decrease in baseflow (BF) and evapotranspiration, respectively. Urbanization led to a significant increase in WY and a reduction in BF, exhibiting strong spatial gradients between urban centers and their peripheries. Increases in forestland decreased WY, while ET showed no significant change due to large absolute values and moisture limitations. Furthermore, the response of BF to forest cover exhibits spatial variation. A negative correlation between BF and forest cover was evident in upstream, whereas no significant correlation was observed in downstream. The findings of this study offer valuable insights for land use planning and sustainable watershed management in semi-arid semi-humid region.

Spatiotemporal changes in future water yield and the driving factors under the carbon neutrality target in Qinghai

The carbon neutrality target has prompted China to restructure its environmental governance system, influencing regional hydrological processes and ultimately affecting future water yield. Considering land use/land cover changes (LUCC) and climate changes, this study examines the impact of China's carbon neutrality target on future water yield. By integrating Future Land Use Simulation and Coupled Model Intercomparison Project datasets, the future water yield is characterized and analyzed under three distinct scenarios: the baseline scenario, carbon neutrality target scenario, and rapid development scenario. Furthermore, the study identifies the dominant driving factors of water yield under different scenarios at both regional and sub-basin scales from 2000 to 2060. Results reveal a clear increase in future water yield with a short-term lag effect of LUCC and climate change. Precipitation emerges as the dominant driving factor of water yield in Qinghai, though its contribution will decrease while vegetation's contribution will increase. The primary driving factors differ across various sub-basins, and the result indicates that maintaining the current land-use policy in Qaidam and Hexi corridor-Alxa Basins is conducive to the improvement of future water yield, while aligning land use with carbon neutrality targets benefits water yield in the Lancang River, Qangtan, Yellow River, and Yangtze River Basins. Notably, this underscores that the pursuit of carbon neutrality goals may not uniformly benefit water yield across all sub-basins. Instead, Qinghai can rely on higher quality and more extensive vegetation to enhance future water yield. This study offers valuable insights that can contribute to the effective management of water resources at the regional level under the carbon neutrality target.

Responses of soil and water-related ecosystem services to landscape dynamics in the eastern Afromontane biodiversity Hotspot

The investigation of soil and water-related ecosystem services (ES) and recognizing the spatiotemporal effects of land-use and land cover changes (LULC) are essential for the formulation of conservation strategies. The research employed the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) and the Revised Universal Soil Loss Equation (RUSLE) models for the assessment of ES. The study was carried out in the Kaffa Forest Biosphere Reserve in Ethiopia, which is part of the eastern Afromontane biodiversity hotspots. The aim of this investigation was to examine and map the temporal and spatial fluctuations in sediment retention, soil erosion, and water yield resulting from LULC modifications between 1986 and 2019, and to provide forecasts for the next three decades. According to the RUSLE analysis, the landscapes exhibited estimated soil losses ranging from zero to 1.5 tons ha-1 yr-1 in 1986, 2009, and 2019, respectively. The mean annual sediment exports for the years 1986, 1999, and 2019 were estimated to be 12.6, 9.9-, and 28.7-tons ha−1, respectively. The water yield of the site experienced a notable increase from 9.8 × 109 m3 in 1986 to 19.6 × 10 9 m3 in 1999, and subsequently rose to 39.3 × 109 m3 in 2019, which is considered to be a disadvantageous to the site. The study found a significant positive correlation between water yield and the expansion of settlement area (r = 0.99, P = 0.015) as well as agricultural land (r = 0.99, P = 0.05). It was also found that significant positive correlation found between vegetation dense area such as forest (r < 0.999, P < 0.001) and shrub & bamboo (r = 0.998, P = 0.036) with sediment retention service. The investigation discovered that there existed tradeoffs between the ES of sediment retention and water yield as the slope increased. The results may be attributed to the presence of dense vegetation cover on the elevated slope regions, rendering them unsuitable for agricultural activities, and the concurrent expansion of arable lands in the lower slope areas, which are flat terrains more conducive to cultivation. The transition from land with more vegetation density to land with lower or no vegetation coverage resulted in an increase in soil loss and water yield, while simultaneously decreasing the sediment retention service. Therefore, the findings can be used as a document to guide decision-makers to design soil-water conservation technologies to enhance the ecological integrity of the biosphere reserve.

Characterization of Ecosystem Services and Their Trade-Off and Synergistic Relationships under Different Land-Use Scenarios on the Loess Plateau

The Loess Plateau is one of the most fragile ecological regions in China due to its shortage of water resources and severe soil erosion. The rapid development of urbanization and the implementation of the project of returning farmland to forest (grass) have caused the ecological environment of the region to be strongly impacted by human activities. It is necessary to investigate the spatial and temporal evolution characteristics of ecosystem services and trade-off/synergy relationships on the Loess Plateau, to achieve scientific management of ecological services and sustainable development of the region. This study quantitatively assesses three ecosystem services of water yield (WY), carbon storage (CS), and soil conservation (SC) on the Loess Plateau under different scenarios from 2000 to 2030 by using the InVEST and PLUS models. Further, the trade-off and synergistic relationships among the ecosystem services have been investigated by Spearman correlation analysis. The results showed that the land-use differences are more obvious under different policy scenarios, with a sharp expansion of constructed land, a gradual increase of forest land, and a continuous decrease of arable land in the Loess Plateau from 2000 to 2020; the water yield and soil conservation increase from 2000 to 2020, and the carbon storage shows an opposite trend. The soil conservation and carbon storage scenarios are the best under the ecological conservation scenario in 2030, while the water yield service is the best under the economic development scenario. There is a synergistic relationship between CS and SC, while there is a trade-off relationship between CS and WY. In addition, there are significant trade-off effects between SC and WY. These results can support guiding land-use management and ecological restoration.

Land use/land cover change and soil property variation increased flood risk in the black soil region, China, in the last 40 years

Land use/land cover change and soil property variation driven by agricultural development substantially affect hydrological processes. Although previous studies have shown that land use/land cover change increases flood risk, how much soil property variation contributes to changes in water yield remains unclear in large-scale regions. Quantifying the water yield response to long-term land use/land cover change and soil property variation in agricultural regions is critical for flood risk control. The black soil area in China was chosen as the study area, and land use/land cover change, soil property variation, and changes in water yield during 1980–2020 were estimated. Land use/land cover change and soil property variation scenarios were established to separate the contributions of land use/land cover change and soil property variation to changes in water yield. The results showed that cultivated land and urban land expanded from 1980 to 2020. The plant available water capacity decreased by 2.10% and 7.27% in the black soil area and typical black soil area, respectively, and the water yield increased by 5.52% and 8.49% in the black soil area and typical black soil area, respectively. Land use/land cover change and soil property variation accounted for 58.64% and 36.67% of the increase in water yield in the black soil area. However, in comparison to land use/land cover change (47.40%), soil property variation (48.77%) accounted for a larger portion of the increase in water yield in the typical black soil area. Both land use/land cover change and soil property variation increased flood risk, however, the effects of soil property variation may exceed those of land use/land cover change, as determined by the spatial scale. This study can provide important information for land use planning and soil hydrological property improvements to reduce flood risk.