Increase In Water Yield Research Articles

Land use changes in Southeastern Amazon and trends in rainfall and water yield of the Xingu River during 1976–2015

Since the early 1970s, the agricultural frontier of southeastern Amazon has undergone extensive land use changes. These alterations, combined with regional climate changes, have the potential to influence the hydrologic cycle at small to large scales. We evaluated a 40-year time series (1976 to 2015) of rainfall and water yield and related them to land use changes in the Upper Xingu River Basin (UX). We acquired data from six rainfall stations and four river gauges and mapped land use changes. Mann-Kendall trend analysis and Pettitt’s change point detection were employed to describe annual and seasonal changes in the time series. Monthly water yield from the Xingu River was used to derive annual, seasonal, and monthly water yield, as well as the runoff coefficient. The largest changes in land use occurred during the last two decades and approximately 60,900 km2 in the Upper Xingu Basin were deforested between 1985 and 2015. Rainfall in the Xingu Basin decreased by about 245 mm over the period but there was no trend in water yield. The number of rainy days and intensity of events also decreased, but the length of the rainy season and seasonal and annual water yield did not change. Although watershed deforestation has increased water yield in other Amazon rivers, the reduction in rainfall in the Upper Xingu Basin was high enough to mask this effect.

Effects of Urbanization on Watershed Evapotranspiration and Its Components in Southern China

Understanding the effects of land use change on evapotranspiration (ET) and its partitioning to transpiration and evaporation is important for accurately evaluating the likely environmental impacts on watershed water supply, climate moderation, and other ecosystem services (e.g., carbon sequestration and biodiversity). This study used a distributed hydrologic model, MIKE SHE, to partition evapotranspiration into soil evaporation, transpiration, ponded water evaporation, and interception, and examined how the ET partitions affected the water balance in the Qinhuai River Basin from 2000 to 2013. Simulated daily ET was compared to measurements at an eddy flux research site during 2016–2017 (R2 = 0.72). Degradation in rice-wheat rotation fields and expansion of impervious surfaces impacted not only total watershed evapotranspiration, which showed a significant downward trend (p < 0.05), but also its partitioning. A significant (p < 0.01) decrease in transpiration was detected. Ponded water evaporation was the only ET partition that exhibited a significant positive trend (p < 0.05). We concluded that the reduced transpiration as a result of land use and land cover change was the primary factor driving the variation of watershed scale evapotranspiration. In addition, there was an increase in annual water yield (23%) as a response to significant reduction in ET (7%) due to a 175% expansion of urban area in the study watershed. Our study provided insights to the mechanisms of land surface–water cycle interaction and better understanding of the effects of land use change on urban micro-climate such as “urban dry island” and “urban heat island” effects.

Forests and Water Yield: A Synthesis of Disturbance Effects on Streamflow and Snowpack in Western Coniferous Forests

AbstractAbstractIn coniferous western forests, recent widespread tree mortality provided opportunities to test the long-held theory that forest cover loss increases water yield. We reviewed 78 studies of hydrologic response to standing-replacing (severe wildfire, harvest) or nonstand-replacing (drought, insects, low-severity wildfire) disturbances, and reassessed the question: Does water yield or snowpack increase after forest disturbance? Collective results indicate that postdisturbance streamflow and snowpack may increase, not change, or even decrease, and illuminate factors that may help improve predictability of hydrologic response to disturbance. Contrary to the expectation that tree mortality reduces evapotranspiration, making more water available as runoff, postdisturbance evapotranspiration sometimes increased—particularly following nonstand-replacing disturbance—because of (a) increased evaporation resulting from higher subcanopy radiation, and (b) increased transpiration resulting from rapid postdisturbance growth. Postdisturbance hydrologic response depends on vegetation structure, climate, and topography, and new hypotheses continue to be formulated and tested in this rapidly evolving discipline.

Impacts of future climate and land use change on water yield in a semiarid basin in Iran

AbstractStudying the interaction between hydrology, land use, and climate change is necessary to support sustainable water resources management. It is unknown how land management interventions in dry climate conditions can benefit water yield in the context of climate and land use change interactions. In this study, we assessed the effects of both land use and predicted climate change on the Mordagh Chay basin water yield using the Integrated Valuation of Ecosystem Services and Tradeoffs model. First, we modeled the current water yield, followed by developing six combined climate–land use scenarios until 2030 based on the CCSM4 climate model for the RCP4.5 and RCP8.5 scenarios. We used three future land use scenarios simulated by the Dyna‐CLUE model. The trend scenario of land use change, which does not include any improvements in irrigation efficiency, significantly affected basin water yield under both climate scenarios. Water yield decreases by 19.8% and 31.8% for the RCP4.5 and RCP8.5, respectively. Under all land use scenarios that included improvements in irrigation efficiency, the water yield responded positively. For the RCP4.5 scenario, the water yield was projected to increase between 16.6% and 18% depending on the land use scenario. The increase in water yield under the RCP8.5 climate scenario was much lower than for the RCP4.5 scenario (about one‐third). Overall, the results showed that by adopting appropriate irrigation efficiency, it is possible to achieve a better balance between environmental needs and regional economic and agricultural development. The results provide insight into possible sustainable development options and also provide guidance for managing the other Urmia Lake sub‐basins, whereas the approach of integrated assessment of climate, land use change, and land management options is also applicable in other conditions to help inform sustainable management.

Effects of dynamic land use/land cover change on water resources and sediment yield in the Anzali wetland catchment, Gilan, Iran

Land use/land cover (LULC) changes strongly affect catchment hydrology and sediment yields. The current study aims at analyzing the hydrological consequences of dynamic LULC changes in the Anzali wetland catchment, Iran. The Soil and Water Assessment Tool (SWAT 2012) model was used to assess impacts on evapotranspiration, water yield, and sediment yield. Two model runs were performed using static and dynamic LULC inputs to evaluate the effects of LULC change between 1990 and 2013. For the static model, the LULC map of 1990 was used, whereas for the dynamic model, a gradual change of the LULC distribution was interpolated from 1990, 2000, and 2013 LULC data. The major LULC changes were identified as an increase of agricultural area by 7% of the catchment area and a decrease of forest coverage by 6.8% between 1990 and 2013. At the catchment scale, the differences in the long-term mean annual values for the main water balance components and sediment yield were smaller than 10 mm (<2.8%) and 3 t/km2 (<2.6%), respectively. However, at the sub-basin scale the increase of agricultural land use resulted in an increase of evapotranspiration, water yield, and sediment yield by up to 8.3%, 7%, and 169%, respectively, whereas urban expansion led to a decrease of evapotranspiration, water yield, and sediment yield by up to −3.5%, −2.3%, and −9.4%. According to the results of the monthly time scale analysis, the most significant impact of LULC changes occurs during the dry season months, when the increase of irrigation agriculture results in an increase in water discharge and sediment loads to the Anzali wetland. Overall, the results showed that the implementation of dynamic LULC change into the SWAT model could be adopted as a planning tool to manage LULC change of the Anzali wetland catchment in the future.

Hydrologic Responses to Climate Variability and Human Activities in Lake Ziway Basin, Ethiopia

Hydrological impacts of human activities and climate variability on Ketar and Meki watersheds of Lake Ziway basin, Ethiopia were studied using the soil and water assessment tool. Three land-use change and two climate variability scenarios were considered to analyze the separate and combined impacts on annual water balance, monthly streamflow, and spatial distributions of evapotranspiration and water yield. The evaluation showed that changes in land use resulted in an increase in annual surface runoff and water yield for Ketar watershed and an increase in annual ET for Meki. Similarly, the climate variability resulted in a decrease in annual ET, surface runoff, and water yield for Ketar watershed and a decrease in ET for Meki. Overall, climate variability has greater impacts on the monthly streamflow compared to land-use change impacts. Similarly, greater sensitivity in hydrologic response was observed for Ketar watershed compared to Meki watershed.

Increased water yield and altered water partitioning follow wildfire in a forested catchment in the western United States

AbstractAs wildfires in much of the western United States increase in size, frequency, and severity, understanding the impact of these fires on water yield from forested headwater basins is essential to successful management of water resources. The current study examines the changes in partitioning of the hydrologic cycle in the Mill Creek Basin that follow the Chippy Creek Fire in Montana, USA, due to alterations to the vegetative regime. The analysis utilizes remote sensing‐based vegetation indices and evapotranspiration, a model‐interpolated precipitation product, and discharge data to assess annual water budgets and vegetative regimes in the Mill Creek Basin. After being almost 90% burned in the Chippy Creek Fire, vegetation in the catchment has shifted from almost exclusively mixed conifer forest to sagebrush scrubs and grasses. This shift in vegetation is accompanied by abrupt shifts in partitioning of the water budget, resulting in an altered ecohydrologic regime. Post‐fire, evapotranspiration decreases annually by 250 mm (46%), and evaporative fraction decreases by 0.53. However, evapotranspiration product biases may overestimate this decrease from pre‐ to post‐fire. This decrease in evapotranspiration results in an annual increase in streamflow of 136 mm, a 21% increase in the runoff ratio, and a 140% increase in water yield. These changes to the water budget are consistent for 10 years post‐fire and show no trend towards pre‐fire values during the study period. Results will help inform planning and management of water resources downstream of forested catchments that have been impacted by wildfire.

Modeling forest management effects on water and sediment yield from nested, paired watersheds in the interior Pacific Northwest, USA using WEPP

The Water Erosion Prediction Project (WEPP) model was applied to seven paired, nested watersheds within the Mica Creek Experimental Watershed located in northern Idaho, USA. The goal was to evaluate the ability of WEPP to simulate the direct and cumulative effects of clear-cutting and partial-cutting (50% canopy removal) on water and sediment yield. WEPP was modified to better represent changes in the Leaf Area Index during post-harvest forest vegetative recovery. Good agreement between simulated and observed streamflow was achieved with minimal to no calibration over a 16-year (1992–2007) period. For the seven watersheds and the entire study period, the overall Nash-Sutcliffe Efficiency (NSE), Kling-Gupta efficiency (KGE), and deviation of runoff volume (DV) between observed and simulated daily streamflow ranged 0.58–0.71, 0.67–0.81, and −4% to 9%, respectively. Good agreement between predicted and observed suspended sediment yield was achieved through the calibration of a single channel critical shear stress parameter. For sediment yield, NSE, KGE, and DV ranged 0.62–0.97, 0.43–0.97, and −2% to 2%, respectively, for the calibration period, and 0.61–0.93, 0.42–0.95, and −24% to 13%, respectively, for the period of model performance assessment. Regression analysis of observed- and WEPP-simulated increase in water and sediment yield following clear-cut treatment was similar; however, the WEPP-simulated increase was lower compared to observations particularly from the partial-cut watershed. The variability in the critical shear parameter for different stream channels in the study watersheds was directly related to the observed mean particle size on the stream bed and suggests that applications of the WEPP model in ungauged basins could potentially set the critical shear parameter based on particle size. Overall, the simulated results demonstrate the potential of WEPP as a modeling tool for forestland watershed management, particularly for estimating the effects of forest harvest on hydrograph fluctuations and consequently, stream sediment transport.

Quantifying Effects of Selected Soil Fertility Management Techniques on Water Use Efficiency in the Central Highlands of Kenya

Declining rainfall distribution and variability lead to low soil moisture amounts and high evapotranspiration rates reducing water use efficiency that negatively affects crop productivity. Various soil fertility management techniques have been put in place to improve soil fertility status, but there is little attempt to asses their effects on water use efficiency and grain yields. The overall objective of the study was to quantify the effects of soil fertility management techniques on water use efficiency in the Central Highlands of Kenya. The experiment was laid out in a randomised complete block design with fourteen treatments replicated four times. Treatments were sole mineral fertilizer (Rf), crop residues + mineral fertilizer (RMf), crop residues + mineral fertilizer + animal manure (RMfM), crop residue + Tithonia diversifolia + animal manure (RTiM), crop residue + Tithonia diversifolia + rock phosphate (RTiP). Data on yield and water use efficiency was analysed using statistical analysis systems software version 9.2 at P=0.05. We observed significant (P&lt;.0001) effect of the treatment on biomass water use efficiency during the short rains 2017, however, there was no significant effect of the treatments on grain water use efficiency because of the frequent dry spells that occurred during the study period. Soil fertility management techniques had a significant effect on grain yield at P&lt;.0001 during the study period. Yields increased significantly (P&lt;0001) under Rf, RMf, RMfM RTiM and RTiP by 90, 110, 120, and 176%, respectively. Water use efficiency also increased significantly under Rf, RMf, RMfM RTiM and RTiP by 200, 140, 180, 129, and 176%, respectively compared to the control. From the study, the combination of organic inputs and mineral fertilisers enhanced water use efficiency and yield hence provides a preferred practise for improved water use efficiency and yield increase.

Impact of Human Activities on Flood Control Capacity of Southern Jiangsu Province in Taihu Basin

Southern Jiangsu Province in Taihu Basin is one of the regions with high urbanization degree in China. In recent years, with the continuous progress of urbanization, the human activities, have further increase the pressure of flood disasters. This paper analyzed the trends of most significant human activities, namely the land use pattern, surface water storage capacity, and construction of polder areas and urban flood control projects; simulated the water yield and water level of regional river network by using a digital watershed model. The results indicated that in the past decades, the construction land expanded significantly, the capacity of flood storage decreased gradually, and the drainage module increased by large-scale construction of polder areas and urban flood control projects. The change of these factors would lead to the increase of the regional water yield and rise of flood level of river network, which would further increase the flood risk of the region.

MAPPING THE EFFECTS OF AGRICULTURAL DEVELOPMENT TO WATER YIELD USING REMOTE SENSING

Abstract. Variation of land cover status, like clearance of forest for agricultural (oil palm) plantation activities, may lead to rapid landscape development. Also, it may cause climate variation effects like excessive rainfall and flooding, which may result in loss of properties and lives. Agricultural (oil palm) plantation‟s dispersed canopy and the open surface of the ground compared to primary forest cause much more runoff and streamflow or discharge. Hence, this paper analyses the land-use changes and evaluate its influence on water yield using the Soil Water Assessment Tools model. Quantitative and qualitative assessment to examine the successive variation from forest to agriculture has been carried out between 2000 and 2010. The results indicate that the conversion of forest to agriculture has a significant influence on hydrological properties of the study area, which cause average water yield increase by 1.93% in the area between 2000 and 2010. Which, in turn, can lead to dryer during the dry season and wetter during rainy seasons. Furthermore, forest and water body are directly proportional. Similarly, forest and agriculture are inversely proportional with R2 &gt; 0.85, p = 0.001. The study shows the ability of Landsat in monitoring the assessment of forest to agriculture, which causes changes in hydrology. This study offers a useful input of planning and sustainable management of surface and water resources.

The impact of forest restoration on agriculture in the Verde River watershed, Arizona, USA

Known as the Four Forest Restoration Initiative (4FRI), the US Forest Service is planning a large-scale restoration of ponderosa pine forests in the Verde River watershed in central Arizona, USA. This paper uses a reduced-form econometric regression model with 1969–2010 time-series data to estimate the economic benefits of the increased water yield due to planned forest restoration of the first phase of 4FRI. We split the data sample into 1969–1989 and 1990–2010 time periods, and conclude during the second time period, water use is statistically and economically significant. This is consistent with the reality that the Verde River watershed has been in drought since the early 1990s. Our central finding is, if water use increases by 1%, the farm income will increase by 1.33%. If a 5–10% increase in water yield caused by the first phase of the 4FRI is all used by agriculture, agricultural income will increase by 6.65–13.3% annually.

Insights from watershed simulations around the world: Watershed service-based restoration does not significantly enhance streamflow

Increased water yield and baseflow and decreased peak flow are common goals of watershed service programs. However, is the forest management often used in such programs likely to provide these beneficial watershed services? Many watershed service investments such as water funds typically change less than 10% of watershed land cover. We simulate the effects of 10% forest-cover change on water yield, low flow, and high flow in hydrologic models of 29 watersheds around the world. The forest-cover changes considered are: forest restoration from degraded natural lands or agriculture, forest conversion to agriculture, and forest conversion to urban cover. We do not consider grassland restoration by removal of alien tree species from riparian zones, which does increase water yield and low flow. Forest restoration from locally-predominant agricultural land resulted in median loss in annual water yield of 1.4%. Forest restoration reduced low flow and high flow by ∼3%. After forest restoration, low flow increased in ∼25% of cases while high flow and water yield declined in nearly all cases. Development of forest to agriculture or urban cover resulted in a 1–2% median increase in water yield, a 0.25–1% increase in low flow, and a 5–7% increase in high flow. We show that hydrologic responses to forest cover changes are not linearly related to climate, physiography, initial land cover, nor a multitude of watershed characteristics in most cases. These results suggest that enhanced streamflow watershed services anticipated from forest restoration or conservation of 10% or less of a watershed are generally modest.

Distinguishing the Relative Contribution of Environmental Factors to Runoff Change in the Headwaters of the Yangtze River

The change in river flows at the basin scale reflects the combined influences of changes in various environmental factors associated with climatic and underlying surface properties. Distinguishing the relative contribution of each of these factors to runoff change is critical for sustainable water resource management, but it is also challenging. The headstream region of the Yangtze River, known as “China’s Water Tower”, has undergone a significant runoff change over the past decades. However, the relative contribution of environmental factors to runoff change is still unclear. Here, we designed a series of detrending experiments based on a grid-based hydrological model to quantify the combined influences of multiple environmental factors on runoff change and the relative contribution of an individual factor to runoff change. The results indicate that changes in climate and vegetation significantly increased water yield in the study basin over the past three decades, and the increase in water yield primarily came from the contribution from the upstream of the basin. On the basin scale, the change in precipitation dominated the runoff change that contributed up to 113.2% of the runoff change, followed by the wind speed change with a contribution rate of −15.1%. Other factors, including changes in temperature, relative humidity, sunshine duration (as a surrogate for net radiation), and albedo (as a surrogate for vegetation) had limited effects on runoff change, and the contribution rate of these factors to runoff change ranged from −5% to 5%. On spatial patterns, the influences of changes in some environmental factors on runoff changes were affected by elevation, particularly for temperature. The rising temperature had mixed effects on runoff change, which generally increased water yield at high altitudes of the basin but decreased water yield at low altitudes of the basin.

Plant Accessible Water Storage Capacity and Tree-Scale Root Interactions Determine How Forest Density Reductions Alter Forest Water Use and Productivity

Forest disturbances such as wildfire and drought-related disease often lead to declines in productivity that both influence and are influenced by forest water use, particularly in the semi-arid environments of the Western US. Fuel treatments are frequently proposed to reduce vulnerability to these drought-related impacts and in some cases as an approach to increase water yield. By changing ecosystem structure, fuel treatments alter ecosystem function (including hydrologic cycling, carbon sequestration, energy partitioning and biogeochemical cycling). Empirical studies of the impacts of changing ecosystem structure, either through active forest management or through natural disturbances, show a wide range of responses that include both increases and decreases in forest water use. Variation in climate and species, as well as the magnitude of forest density reduction, are commonly proposed as explanations for this variation. In this paper we use a coupled eco-hydrologic model to demonstrate that subsurface features are likely to be a critical, but often over-looked, factor that influences forest water use and regeneration following density reduction treatments. Using a case study site in the southern Sierra Nevada Mountains of California, we show that whether forest water use increases or decreases following density reduction, as well as the magnitude and rate of recovery of hydrologic changes, depends strongly on plant accessible water storage capacity within the rooting zone and the extent to which the root structures of neighboring trees interact and share water. We find that in some cases density reduction can increase water yield and productivity of remaining trees for the first few years following treatment. However we also show that when soils are shallow and roots systems overlap, counter-intuitive increases in water use and related declines in productivity can occur due to water stress. Results highlight the importance of accounting for site-specific variation, such as soil water storage capacity, in assessing how fuel treatments may interact with ecosystem water use and drought vulnerability, and ultimately downslope impacts on streamflow.

Impacts of land use land cover change on runoff and sediment yield of Upper Tapi River Sub-Basin, India

ABSTRACTLand use land cover (LULC) changes can result in shortage of water, flood risk and soil erosion and thus contribute to the deterioration of living conditions. Understanding the impacts of LULC changes on water resources is therefore an important research issue for watershed management. Therefore, this paper discusses the impacts of LULC changes on surface runoff and sediment yield of Upper Tapi River Sub-basin, India using Soil and water assessment Tool (SWAT). The land use dynamics of the sub-basin was assessed through the analysis of four land use maps corresponding to year 1975, 1990, 2000, and 2016. It is found that from the year 1975–2016 agricultural area is increased by 18% whereas forest land and rangeland are decreased by 7% and 10% respectively. This land use change may lead to land degradation and ecological damages in the study area. These LULC maps were used to calibrate four separate SWAT models with the corresponding climate data from 1979 to 2013. These models performance are evaluated based on R2, ENS and PBIAS values which indicate very good agreement between observed and simulated discharge. The impacts of LULC changes were assessed by four different scenarios in which climate data (1979–2013), Soil map and slope map were kept same, and only the land use maps were changed. The results of this study showed that LULC changes have resulted in corresponding increase in surface runoff, water yield, and sediment yield. The surface runoff has increased about 36% and water yield has increased about 22%. Similarly, sediment yield is also increased around 22% from the scenario S1 to S4. The outputs of this study could be used for soil and water conservation and river health protection in the Upper Tapi River Sub-Basin.

Impact of Climate Change on Water Resources in the Kilombero Catchment in Tanzania

This article illustrates the impact of potential future climate scenarios on water quantity in time and space for an East African floodplain catchment surrounded by mountainous areas. In East Africa, agricultural intensification is shifting from upland cultivation into the wetlands due to year-round water availability and fertile soils. These advantageous agricultural conditions might be hampered through climate change impacts. Additionally, water-related risks, like droughts and flooding events, are likely to increase. Hence, this study investigates future climate patterns and their impact on water resources in one production cluster in Tanzania. To account for these changes, a regional climate model ensemble of the Coordinated Regional Downscaling Experiment (CORDEX) Africa project was analyzed to investigate changes in climatic patterns until 2060, according to the RCP4.5 (representative concentration pathways) and RCP8.5 scenarios. The semi-distributed Soil and Water Assessment Tool (SWAT) was utilized to analyze the impacts on water resources according to all scenarios. Modeling results indicate increasing temperatures, especially in the hot dry season, intensifying the distinctive features of the dry and rainy season. This consequently aggravates hydrological extremes, such as more-pronounced flooding and decreasing low flows. Overall, annual averages of water yield and surface runoff increase up to 61.6% and 67.8%, respectively, within the bias-corrected scenario simulations, compared to the historical simulations. However, changes in precipitation among the analyzed scenarios vary between −8.3% and +22.5% of the annual averages. Hydrological modeling results also show heterogeneous spatial patterns inside the catchment. These spatio-temporal patterns indicate the possibility of an aggravation for severe floods in wet seasons, as well as an increasing drought risk in dry seasons across the scenario simulations. Apart from that, the discharge peak, which is crucial for the flood recession agriculture in the floodplain, is likely to shift from April to May from the 2020s onwards.

Spatiotemporal heterogeneity and influencing mechanism of ecosystem services in the Pearl River Delta from the perspective of LUCC

Land use/land cover change (LUCC) has considerable impact on ecosystem services. It is essential to quantify the spatiotemporal heterogeneity of ecosystem services from the perspective of LUCC, which will benefit regional land management and ecological protection. We analyzed land use change in the Pearl River Delta from 2000 to 2015, and we used a spatially explicit integrated modeling tool (InVEST) for quantification of ecosystem services–water yield, carbon storage, soil retention, and food supply. The results revealed increases in the areas of grassland and built-up land, and decreases in the areas of woodland, cropland, water body, and unused land during 2000 to 2015, which have caused increase in water yield and carbon storage, while decrease in soil retention and food supply. The dynamic changes of woodland, grassland, cropland, and built-up land were the main driving factors in the relationship of trade-offs and synergies among the four ecosystem services, which are ubiquitous. Those all illustrate the importance of considering ecosystem services in decision making related to land use and land management.

Modelling Development of Riparian Ranchlands Using Ecosystem Services at the Aravaipa Watershed, SE Arizona

This paper describes how subdivision and development of rangelands within a remote and celebrated semi-arid watershed near the US–Mexico border might affect multiple ecohydrological services provided, such as recharge of the aquifer, water and sediment yield, water quality, flow rates and downstream cultural and natural resources. Specifically, we apply an uncalibrated watershed model and land-change forecasting scenario to consider the potential effects of converting rangelands to housing developments and document potential changes in hydrological ecosystem services. A new method to incorporate weather data in watershed modelling is introduced. Results of introducing residential development in this fragile arid environment portray changes in the water budget, including increases in surface-water runoff, water yield, and total sediment loading. Our findings also predict slight reductions in lateral soil water, a component of the water budget that is increasingly becoming recognized as critical to maintaining water availability in arid regions. We discuss how the proposed development on shrub/scrub rangelands could threaten to sever imperative ecohydrological interactions and impact multiple ecosystem services. This research highlights rangeland management issues important for the protection of open space, economic valuation of rangeland ecosystem services, conservation easements, and incentives to develop markets for these.

Effect of deforestation on access to clean drinking water

Using satellite data on deforestation and weather in Malawi and linking those datasets with household survey datasets, we estimate the causal effect of deforestation on access to clean drinking water. In the existing literature on forest science and hydrology, the consensus is that deforestation increases water yield. In this study, we directly examine the causal effect of deforestation on households' access to clean drinking water. Results of the two-stage least-squares (2SLS) with cluster and time fixed-effect estimations illustrate strong empirical evidence that deforestation decreases access to clean drinking water. Falsification tests show that the possibility of our instrumental variable picking up an unobserved time trend is very unlikely. We find that a 1.0-percentage-point increase in deforestation decreases access to clean drinking water by 0.93 percentage points. With this estimated impact, deforestation in the last decade in Malawi (14%) has had the same magnitude of effect on access to clean drinking water as that of a 9% decrease in rainfall.