ArticlePDF Available

Rehabilitation of degraded rangelands in Jordan: The effects of mechanized micro water harvesting on hill-slope scale soil water and vegetation dynamics

Authors:
Stefan Martin Strohmeier at University of Natural Resources and Life Sciences Vienna
Stefan Martin Strohmeier
Sayo Fukai at Tottori University
Sayo Fukai
Mira Haddad at International Center for Agricultural Research in the Dry Areas (ICARDA)
Mira Haddad
Mohammad Alnsour at Wadi fo Sustainable Ecosystem Development NGO
Mohammad Alnsour
  • Wadi fo Sustainable Ecosystem Development NGO
Show all 9 authorsHide
Download full-text PDF
Read full-text
Download citation

Abstract and Figures

Overexploitation and climate change accelerate the degradation of Jordan's arid rangelands. Uncovered and crusted soils increase runoff and erosion and hinder the emergence of the native vegetation. Micro water harvesting combined with shrub-seedling plantation have been widely applied to reverse land degradation trends. However, consequential soil water and vegetation dynamics have been rarely assessed, which constrains further out-scaling of the rehabilitation practice to complex environments. In Jordan, an experiment was set up to study the linkages between local rainfall characteristics, soil moisture and the development of out-planted shrub-seedlings. Soil moisture was recorded at approximately weekly time-interval during the rainy and dry season 2017/2018 using a manually operated soil water sensor. Transect monitoring was pursued up and down the slope across four micro water harvesting pits and the interspaces. Data confirmed a significant soil moisture increase inside the pits-bridging intra-seasonal dry spells and soil water potentially deep-percolated into the karstic bedrock underneath. The study found that the out-planted shrubs' stem diameter and height predominantly increased during post rainy season, when the interspaces dried up while the pits continued providing moisture. The results are promising and contribute to integrated research towards halting land degradation and sustainable agro-pastoral development.
Figures - uploaded by Stefan Martin Strohmeier
Author content
All figure content in this area was uploaded by Stefan Martin Strohmeier
Content may be subject to copyright.
Content uploaded by Stefan Martin Strohmeier
Author content
All content in this area was uploaded by Stefan Martin Strohmeier on Oct 18, 2020
Content may be subject to copyright.
Journal of Arid Environments 185 (2021) 104338
0140-1963/© 2020 Elsevier Ltd. All rights reserved.
Rehabilitation of degraded rangelands in Jordan: The effects of mechanized
micro water harvesting on hill-slope scale soil water and
vegetation dynamics
S. Strohmeier
a
,
*
, S. Fukai
b
, M. Haddad
a
, M. AlNsour
c
, M. Mudabber
d
,
1
, K. Akimoto
b
,
S. Yamamoto
b
, S. Evett
e
, T. Oweis
a
a
International Center for Agricultural Research in the Dry Areas (ICARDA), Beirut, Lebanon
b
Tottori University, Tottori, Japan
c
Watershed and Development Initiative (WADI), Amman, Jordan
d
National Agricultural Research Center (NARC), Amman, Jordan
e
USDA ARS Soil and Water Management Research Unit, Bushland, TX, USA
ARTICLE INFO
Keywords:
Rangeland rehabilitation
Land degradation
Surface runoff
Soil moisture
Erosion
ABSTRACT
Overexploitation and climate change accelerate the degradation of Jordan’s arid rangelands. Uncovered and
crusted soils increase runoff and erosion and hinder the emergence of the native vegetation. Micro water har-
vesting combined with shrub-seedling plantation have been widely applied to reverse land degradation trends.
However, consequential soil water and vegetation dynamics have been rarely assessed, which constrains further
out-scaling of the rehabilitation practice to complex environments. In Jordan, an experiment was set up to study
the linkages between local rainfall characteristics, soil moisture and the development of out-planted shrub-
seedlings. Soil moisture was recorded at approximately weekly time-interval during the rainy and dry season
2017/2018 using a manually operated soil water sensor. Transect monitoring was pursued up and down the slope
across four micro water harvesting pits and the interspaces. Data conrmed a signicant soil moisture increase
inside the pits - bridging intra-seasonal dry spells and soil water potentially deep-percolated into the karstic
bedrock underneath. The study found that the out-planted shrubs’ stem diameter and height predominantly
increased during post rainy season, when the interspaces dried up while the pits continued providing moisture.
The results are promising and contribute to integrated research towards halting land degradation and sustainable
agro-pastoral development.
1. Introduction
Jordan is located at the transition zone of the eastern Mediterranean
towards the dry rangeland and desert landscape called ‘Badia’, which
occupies a vast expanse in the east and the south of the country. Around
90% of Jordan’s territory is considered Badia (Ababsa, 2013) and re-
ceives less than 200 mm average annual rainfall. However, despite its
marginal conditions the Badia areas are vital to the country, especially
for agro-pastoralism (Al-Tabini et al., 2012). Over the past decades,
unsustainable land management including mechanized
mono-agriculture and overgrazing by small ruminant herds have
severely degraded Jordan’s Badia soils, native biomass and biodiversity
(Abu-Zanat et al., 2004). Political conicts in the region and the
consequential migration including livestock herders, e.g. as a result of
the 1990s Gulf War (Payne, 2016), added further pressure on the natural
resources. Myint and Westerberg (2014) claim that the palatable dry
biomass production of the Jordanian Badia halved from the 1990s to
2010, which progressively altered the livestock feed supply system.
Grazing routines practiced in Jordan’s drylands, nowadays, mainly
serve health and reproduction purposes rather than covering the live-
stock’s feed demand. Wide Badia areas have been transformed into
sparsely vegetated lands with a crusted soil surface (Oweis, 2017). The
declining rainwater retention and inltration characteristics of the soils
eventually speed up surface runoff and erosion (Strohmeier et al., 2017;
* Corresponding author. C/o National Agricultural Research Center (NARC), Jerash Road, Baqa’, Jordan.
E-mail address: s.strohmeier@cgiar.org (S. Strohmeier).
1
retired.
Contents lists available at ScienceDirect
Journal of Arid Environments
journal homepage: www.elsevier.com/locate/jaridenv
https://doi.org/10.1016/j.jaridenv.2020.104338
Received 14 April 2020; Received in revised form 11 October 2020; Accepted 12 October 2020
... Water harvesting is defined as the collection of runoff flows for productive purposes (Critchely, 1991); WHTs aim to collect and store water in times of excess (e.g., heavy rainstorms and flood events) and release it in situations of shortage (Mekdaschi Studer & Liniger, 2013). This results in better water availability over time and represents one of the most important approaches for coping with water shortages and temporal variation in arid and semi-arid regions (Castelli et al., 2018; M. Rockström & Falkenmark, 2015;Strohmeier, Fukai, et al., 2021;. The ratio between the water-collecting Catchment size and targeted Cultivated Area (C:CA) is commonly used to classify water harvesting systems. ...
... Furthermore, erroneous reports on dryland threats, their causes and consequences, unsustainable management of natural resources (Al-Adamat et al., 2010) and the lack of well-targeted methodologies and design (Ziadat et al., 2012) slow down the implementation. However, increasing efforts are being undertaken to evaluate the performance of WHTs in Jordan's Badia under local communities' management, including the scientific assessment of mechanized micro water harvesting conducted by M. , M. , Strohmeier, Fukai, et al. (2021), and Tatsumi et al. (2021). ...
... With the aim to enhance indigenous knowledge-based technologies' performances and to fill the gap between actual and potential rainfed production, the International Center for Agricultural Research in the Dry Areas (ICARDA) and the National Agricultural Research Center (NARC) of Jordan, together with the local community, developed a pilot watershed in the Jordanian Badia: the Badia Research Site (BRS) (Dhehibi et al., 2020;Mudabber, 2017;Strohmeier, Fukai, et al., 2021;Tatsumi et al., 2021, Figure 2). The BRS has been equipped with a combination of WHTs to rehabilitate degraded rangelands: in the upper part of the watershed, a mechanized Vallerani micro-catchment intervention was implemented to capture the excess rainfall for increased shrub-forage production and to reduce surface runoff and consequential erosion along the steep hillslopes. ...
Modeling-based performance assessment of an indigenous macro-catchment water harvesting technique (Marab) in the Jordanian Badia
Article
Full-text available
  • Nov 2023
  • LAND DEGRAD DEV
Water resources management is fundamental for rural communities in drylands, where water harvesting technologies (WHT) can be used for intercepting surface runoff and storing water in soils. The so-called "Marab" WHT was initially developed by Middle Eastern agro-pastoralists that reside or commute in semi-arid and arid ran-gelands. The Marab WHT is a macro-catchment measure consisting of earth dams and stone spillways along the contours of a lowland depression or floodplain. Dependent on the local context (i.e., climate, soil, management, etc.), the established Marabs show highly variable effectiveness and little scientific evidence is supporting the scaling out of the technology. This study aims at filling the knowledge gap on the Marab performance in different environments by simulating its hydro-agrological effects for different soils and climatic conditions using the AquaCrop model. A case study performed for a Jordanian Marab over three seasons (2019-2022) confirms its huge improvement potential for barley production. Through Marab-based farming, barley production reached 8.37 t ha À1 on average, versus highly variable 0.34 t ha À1 without the WHT. The simulation-based assessment of soil textures identified that silty soils have the largest potential for producing up to 9.25 t ha À1 barley, compared to 6.60 t ha À1 produced in clay soils. Assessing different climate scenarios, a slight increase in daily average temperatures (+0.5 C) led to a considerable production decline of 4%-8%, while a significant reduction of precipitation (À20%) decreased biomass production by a similar rate (4%-10%). This underlines the robustness of the "Marab" WHT to rainfall amount variation. However, simulations also highlight the sensitivity of timing and frequency of flood events: removing the last and the first flood event reduced biomass production by approximately 50% and 80%, respectively , while the barley fails to develop if both events were suppressed.
View
... Pitting as a mechanical reclamation technique has been used widely in pastoral areas worldwide, particularly in the Middle East and the United States (Jahantigh & Pessarakli 2009;Zarekia et al. 2018;Strohmeier et al. 2021). Pitting has also been used by traditional cultures for millennia, particularly in the Middle East, Asia, Africa, and North America (Evenari et al. 1971;Vetter et al. 2009). ...
... Indeed, as early as the late 1970s, Stanley (1978b) reported that nine out of the 17 trials in the area (including the current 14 trials) had poor to fair future prospects, consistent with our long-term synopsis. Current and more successful engineering-based rangeland rehabilitation practices are based on the construction of much larger structures such as contour furrows, water ponds, dikes, bunds, and banks that hold greater volumes of water and have a longer life expectancy (Gammoh 2013;Klik et al. 2018;Strohmeier et al. 2021). Some of the trial sites in the present study have since been rehabilitated using more appropriate technology such as water ponding, which is highly successful on long, low sloping soils (Thompson 2008). ...
Pitting fails to sustain increases in ecosystem structure in arid rangelands
Article
  • May 2023
Mechanized approaches to the rehabilitation of degraded rangeland have been extremely popular since the early 1930s but their effectiveness depends on climatic and environmental conditions (e.g. soil texture, pre‐treatment plant cover). We evaluated the effects of pitting, a popular rehabilitation technique based on the creation of elongated soil depressions (pits), on ecosystem structure from 14 trials conducted at 10 sites across an extensive area (~100,000 km ² ) of rangelands in eastern Australia. Averaged across all sites and rehabilitation times, pitting had a significant positive effect on the cover of perennial forbs and annuals, and suppressed bare ground compared with untreated sites. However, these treatment effects varied with different site conditions such as soil texture, and pre‐treatment rainfall and plant cover among individual sites. Pre‐treatment plant cover, and rainfall in the 3 months prior to measurements increased the effects of pitting on litter cover, and time since treatment increased the relative effect of pitting on annual plant cover. Negative effect of pitting on the cover of bare soil declined with increasing rainfall. Soil moisture was generally greater beneath pits than either control soils or soils between the pits (inter‐pits). Despite some positive effects on annual plant and litter cover, pitting effects were generally short lived, suggesting that a single pitting treatment may fail to achieve long‐term rehabilitation. Given that these field trials were conducted half a century ago under conditions of higher average rainfall, the prognosis for the success of pitting under current conditions of lower rainfall and higher temperature is generally poor.
View
... cerns/soils/soil-health/soil-health-assessment ; accessed September 10, 2022). However, future climatic trends may lead to increased occurrence of extreme erosion events and lead to more soil pore sealing and crusting effects (Strohmeier et al., 2021). Under NT soil compaction risk seems larger in the deeper layers; high bulk densities suggest a low volume of pore space and a reduced ability to store water (Fernandes et al., 2011). ...
Long-term effects of tillage systems on soil health of a silt loam in Lower Austria
Article
Full-text available
  • Apr 2024
  • SOIL TILL RES
Tillage is an essential practice for soil preparation in agriculture that influences a broad variety of soil parameters. However, the long-term implications of tillage on soil health are complex, context specific, and need to be better understood. The aim of our study is to evaluate soil physical, chemical, and biological effects of three different tillage practices: conventional tillage (CT), mulch tillage (MT), and no-till (NT). A long-term experiment in Mistelbach, Lower Austria, was launched in 1994 and comprehensively sampled in 2002 and 2021. To evaluate tillage-impacts over the two decadal monitoring we assessed soil health indicators in the 0–20 cm soil depth (conventional ploughing layer) and below 20 cm. A "Soil Management Assessment Framework" (SMAF) procedure was applied to assess and compare soil quality using the Soil Quality Index (SQI). Considering multiple indicators, we found overall quality improvements in all three tillage-experiments over time. However, particularly the conservation practices (MT and NT) enhanced soil quality, predominately soil organic carbon (SOC) and soil physical indicators (e.g. water holding capacity, coarse pores). The study confirms that SOC in the 0–20 cm layer significantly increased under no-till (46 Mg C ha−1) compared to conventional tillage (26 Mg C ha−1). At the same time aggregate stability and water holding capacity increased under conservation agriculture (MT and NT). The proven positive impacts on soil health will further help to promote agricultural practices that sustain productivity while pushing forward climate change mitigation actions in temperate climate.
View
... Water harvestingthe collection of runoff water for productive purposes (Critchley and Siegert, 1991) is a common practice in arid and semi-arid regions. Beyond their primary role of collecting and storing water for domestic, agricultural or industrial use, water harvesting structures can have many other benefits, including increased plant biomass production, recharge of aquifers, reduced soil erosion, and flood mitigation (Gupta, 1994;Abdeldayem et al., 2020;30 Parimalarenganayaki, 2021;Strohmeier et al., 2021). There are many factors that need to be considered when deciding whether a location is appropriate for development as a water harvesting site, and several different methodologies have been deployed to identify sites. ...
HRRTLE (High Resolution Runoff and Transmission Loss Estimator): a novel tool for mapping connectivity of runoff in ephemeral stream networks to aid the siting of water harvesting structures
Preprint
Full-text available
  • Apr 2024
Water harvesting is predominantly carried out in arid and semi-arid regions. Site selection studies often rely on a methodology that calculates runoff using curve numbers to generate runoff maps. These maps, typically used as part of a multi-criteria selection process, identify areas conducive to the siting of water harvesting structures. However, traditional runoff maps do not account for transmission losses that occur along the surface flow path to the catchment outlet, and these losses can be significant in arid and semi-arid regions. Here we introduce a methodology that incorporates a curve number runoff method while also addressing transmission losses. Our approach, utilising three global datasets, was validated against observed runoff data from 28 catchments worldwide, and infers hydraulic characteristics of both overland and channel flow from curve number values. This involves leveraging the curve number dataset twice: initially for calculating runoff and subsequently for forecasting transmission losses. The outcomes include a runoff connectivity map, at a spatial resolution of 250 m × 250 m, presenting the runoff depth (in mm) for each pixel based on the direct runoff generated at that pixel and reaching the catchment outlet. This connectivity map aids planners in comprehending the dynamics of surface runoff towards a catchment outlet, assisting in identifying potential locations for future water harvesting structures. The process integrates 38 years of precipitation data, enabling predictions not only for average annual runoff but also for the return periods of various annual runoff volumes. Despite the simplicity of the model, a positive Nash-Sutcliffe efficiency value was observed in 11 out of the 28 catchments.
View
... Subsurface runoff generation is also significantly influenced by crop cover variations and types of tillage practices, especially in red soil (El Kateb et al. 2013;Steudel et al. 2015;Strohmeier et al. 2021). Due to long-term artificial tillage and natural processes of soil formation, the red tillage soil on the slope is stratified and consists of a loose, porous, and highly permeable top layer, and a compact and weakly permeable bottom layer (Jonard et al. 2013;Ma et al. 2022). ...
Effects of ridge tillage and peanut growth on the surface–subsurface runoff generation and soil loss in the red soil sloping farmland of southern China
Article
Full-text available
  • Feb 2024
  • J SOIL SEDIMENT
Purpose Proper tillage management and crop plantation are two established approaches to control soil erosion in red soil slopes of southern China. This study aims to investigate the surface–subsurface runoff and soil losses processes on sloping farmland under different peanut growth stages and ridge treatments, and to quantify the combined effects of proper tillage management and crop plantation. Methods Simulated rainfall experiments with an intensity of 60 mm h⁻¹ were conducted to measure the initiation time and steady rates of surface–subsurface runoff and soil losses under four tillage treatments including flat planting (FP), longitudinal ridge (LR), cross ridge (CR), and alternate distribution of cross and longitudinal ridges (CL) at the bare land and four different growth stages of peanut. Results As peanut grew, the mean steady surface runoff rate for all treatments decreased by 19.6%, 38.8%, 54.0%, and 66.3% at the four growth stages respectively, and the mean steady subsurface runoff rate increased by 35.4%, 77.3%, 99.9%, and 118.4% at the four growth stages respectively. The maximum soil loss rate also decreased from 7.33 ~ 25.92 g m⁻² min⁻¹ at the seedling stage to 0.31 ~ 4.72 g m⁻² min⁻¹ at the full fruit stage. Compared with the FP treatment, the steady surface runoff rate for the LR treatment increased by 8.1 ~ 32.4% and the steady subsurface runoff rate reduced by 7.2 ~ 38.4%; while for the CR treatment, the steady surface runoff rate reduced by 77.6 ~ 92.7% and the steady subsurface runoff rate increased by 26.6 ~ 219.3%. As peanut grew, the contribution index of peanut to surface runoff increased from 0 at bare land stage to 0.80, 0.96, and 0.34 for the LR, CL, and CR treatment at the S4 stage, while the contribution index of ridge tillage to runoff generally decreased. Conclusions The inhibitory effects of peanut on surface runoff rate and sediment yield, as well as its promotion effect on subsurface runoff, were enhanced with peanut growth. Conversely, the impact of ridge tillage gradually decreased as peanut grew. On plots with longitudinal ridges, the impact of ridges on runoff was offset by contribution of crop growth after the seedling stage; whereas on plots with only contour ridges, the impact of ridges continued to dominate runoff control as peanut grew.
View
... The high percentage of positive evidence on ES provided by AS found in this study emphasizes the need to develop more research in this region. Moreover, in the articles reviewed, we found that shrubs are the species most used in AS of arid lands, mainly from Chenopodiaceae family (Derib et al. 2009;Strohmeier et al. 2021). The ecological adaptations of shrubs to arid lands allow them to grow in environments with extreme solar radiation, frequent droughts, high soil salinity and alkalinity (Dagar and Gupta 2020). ...
Could agroforestry restore ecosystem services in arid lands? An analysis through the weight of the evidence approach
Article
Full-text available
  • Dec 2023
  • AGROFOREST SYST
Degradation is limiting the ability of arid lands to provide ecosystem services. Agroforestry Systems can supply several of these ecosystem services. In this context, we carried out a systematic review of literature, to find the ecosystem services provided by Agroforestry Systems in arid lands irrigated by rainwater harvesting systems in worldwide. The ecosystem services most mentioned (soil quality, productivity increase, carbon sequestration, biodiversity conservation, cultural values, water regulation and purification, and pollination), that were provided by the four Agroforestry Systems (protein banks, intercropping, windbreaks and homegardens) were used to apply the Weight of Evidence Approach. The regions where Agroforestry Systems practices were carried out, the species most used and their multipurpose were also evaluated. Most of the experiences were documented in Africa (42%) and Asia (37%). We registered 82 species, being the Fabaceae and Chenopodiaceae families were the most used. These species (49% shrubs) were mainly integrated in Agroforestry Systems by homegardens (43%), intercropping (40%), and windbreaks (23%). The most evaluated species uses were medicine (58%), food (28%), and forage (27%). We found several positive evidence of Agroforestry Systems in all ecosystem services evaluated. We also found some evidence that Agroforestry Systems can cause drawbacks such as salinization, or species invasion.
View
... These earthworks are able to increase water infiltration rates and store moisture from rainfall events for significantly longer periods than in the unmodified surrounding environments. Furrows and pits have been shown to be particularly good at storing moisture and increasing plant survival (Strohmeier et al. 2021), but creating such earthworks often requires machinery and other specialized equipment for construction that is not only expensive but also can disturb the soil surface (Stavi et al. 2020). In this regard, smaller-scale earthwork options are also available to reduce concerns about disturbance. ...
A global review on arid zone restoration: approaches and challenges
Article
Full-text available
  • Dec 2023
Arid environments have become degraded in recent times through human activity highlighting the need for restoration works to reverse this trend. One of the most common forms of restoration works is revegetation. However, revegetation is difficult in the arid zone due to a combination of environmental factors such as low moisture and extreme temperatures, as well as financial and administrative factors. In this review, we investigated the literature describing various methods available for arid revegetation, and assess their utility for revegetation activities. Each of the methods investigated were found to have potential advantages and disadvantages, though some general trends were observed. Two main planting methods were identified, “out‐planting” and “direct seeding.” Which of these methods to use depends on the conditions of the project being undertaken. Out‐planting appeared to be the most suited approach to smaller scale projects with higher budget availability, whereas direct seeding was more suited to large scale, lower budget projects. Weed control prior to planting was identified as being critical for success in most works, whereas soil ripping was beneficial for direct seeding projects. Among the soil amendments investigated, water‐holding gels were most likely to be beneficial, whereas fertilizers were riskier due to their potential to reduce drought tolerance and increase weed invasion. Microbial inoculation with mycorrhiza showed high potential to improve plant performance but may be held back by the lack of suitable commercial sources. Newer seed technologies, such as synthetic seed coats and pellets, show promise, but this issue still requires further research and development.
View
Impact of temperature and residence time on sewage sludge pyrolysis for combined carbon sequestration and energy production
Article
Full-text available
  • Mar 2024
Environmental challenges related to sewage sludge call for urgent sustainable management of this resource. Sludge pyrolysis might be considered as a sustainable technology and is anticipated to support measures for mitigating climate change through carbon sequestration. The end products of the process have various applications, including the agricultural utilization of biochar, as well as the energy exploitation of bio-oil and syngas. In this research, sewage sludge was pyrolyzed at 500 °C, 600 °C, 750 °C, and 850 °C. At each temperature, pyrolysis was explored at 1hr, 2hrs, and 3hrs residence times. The ratio (H/Corg)at was tapped to imply organic carbon stability and carbon sequestration potential. Optimum operating conditions were achieved at 750 °C and 2hrs residence time. Produced biochar had (H/Corg)at ratio of 0.54, while nutrients’ contents based on dry weight were 3.99%, 3.2%, and 0.6% for total nitrogen (TN), total phosphorus (TP), and total potassium (TK), respectively. Electrical conductivity of biochar was lesser than the feed sludge. Heavy metals in biochar aligned with the recommended values of the International Biochar Initiative. Heat content of condensable and non-condensable volatiles was sufficient to maintain the temperature of the furnace provided that PYREG process is considered. However, additional energy source is demanded for sludge drying.
View
MODELING OF RANGELAND ECOSYSTEMS IN NORTHERN JORDAN
Conference Paper
  • Oct 2023
Grasslands is globally important vegetation type for providing feed resources for grazing animals. An improved understanding of the factors affecting the long-term productivity of the ecosystems will be beneficial, as well as to developing a better understanding of the role these ecosystems play in global environmental change. Arid and semi-arid Mediterranean grasslands provide valuable forage for grazing animals in the eastern part of the Mediterranean area and have been subjected to long-term unsustainable grazing practices, leading to degeneration of productivity and impacts plant community structure. The present study aimed to discover the validity of using Phytomass Growth Simulator Model (Phygrow) to simulate arid grassland ecosystems. The purpose is to build a Phygrow simulation model that can accurately estimate important eco-hydrological processes in arid grassland ecosystems. The weather parameter was taken from the NASA (National Aeronautics and Space Administration). Important vegetation parameters and other key processes were simulated during the period 1981�2021 using the Phygrow model. The simulation was conducted for a grassland community within the Jordan University of Science and Technology JUST Campus. The model was able to reproduce all the general trends found in the study area, where peak growth is reached during the spring and ceased during the summer for annual spring growing species. The model has been successfully able to simulate leaf area index, evapotranspiration, soil moisture, leaf water storage, water stress, and temperature stress from 1981 to 2021.
View
Climate Risk Management with Indigenous Knowledge and Perception—Evidence from Drought Prone Regions of India
Chapter
Full-text available
  • May 2023
There are many indigenous and traditional knowledge systems that have been in practice for centuries among local communities of arid regions of India. Local communities use their traditional knowledge to predict drought and take agricultural decisions. Through evidence-based fieldwork and focus group discussions with the local communities in the villages in western Rajasthan and arid districts of Gujarat, this study tries to document all the indigenous practices and traditional knowledges that claim to predict drought and mitigate drought. The study shows that local communities can predict drought at a large extent that can be validated through meteorological and other scientific data. We argue there is no “one-size-fits-all-solution” because solutions take many shapes and forms, depending on the unique context of a community, specific challenges, and its location. While climate mitigation policies to reduce climate change are taken at the global scale and can be top-down, the climate adaptation policies need to be local and bottom up. Risk reduction and adaptation strategies need to be user-friendly in its application where local knowledge and scenarios are meaningful at the community level to help communities to manage their vulnerabilities while equipping themselves with the necessary measures to curb their future risks. If local people are made aware of and comprehend their exposure to risk and potential impacts, they can take the initiative to make decisions based on existing trade-offs. Thus, strengthening interactions among local communities, scientists and policymakers should be a key commitment to foster effective and timely policy decision.
View
Resolving discrepancies between laboratory-determined field capacity values and field water content observations: implications for irrigation management
Article
Full-text available
  • Jul 2019
The concept of soil water contents at field capacity (FC at 0.33 MPa) and at wilting point (WP at 15 MPa) is often used to explain plant water availability and as maximal and minimal limits on observed soil water content. Field observations often differ, however, from laboratory-determined FC and WP water content values. Moreover, as more capable sensors have become available and graphical plots of soil water dynamics have become common, plotting of FC and WP lines on such graphs often reinforces these differences and engenders confusion rather than enlightenment. Resolving this confusion has been greatly eased by the introduction of soil water sensors that encapsulate an entire time domain reflectometry (TDR) system in individual sensor heads and the recent availability of a reader for capturing georeferenced values of the TDR waveform and estimated values of soil volumetric water content (VWC), permittivity, temperature, and bulk electrical conductivity. The present study illustrates the typical confusion with season-long graphs of soil water content that greatly exceed the FC values for individual soil horizons, and it resolves the confusion with concurrent and co-located TDR sensor readings and volumetric soil sampling to ascertain sensor accuracy. It was found that sensor readings were reasonably accurate (RMSE = 0.01 m³ m⁻³) across a range of textures from fine sandy loam to clay, even though some measurements were up to 0.19 m³ m⁻³ larger than FC values. Water contents in a sandy eluviated horizon above a dense clay were larger than FC due to the clay layer impeding water flow and perching water in the sand, augmented by the capillary fringe in the fine sand. Confusion was in part created by plotting water content for four different depths of different textures but plotting the FC and WP values for only one soil texture. Misperception of water available for crops was greatly reduced by converting the water content values to equivalent water depth values for the four soil layers and plotting only the soil water storage depth for the entire profile depth covered by the sensing network. The ambiguity was further reduced by determining the maximum value of soil water storage for the season and calculating soil water depletion by subtracting the maximum value from the soil water storage throughout the season. When this was done, it was easy to see depths of water removed from the soil and needing replacement, and to see the extra soil water depletion that occurred when a plot was not irrigated.
View
The Effectiveness of Continuous Contour Ridges and Intermittent Trenches Constructed Using the Vallerani in Water Harvesting in Arid Regions
Article
Full-text available
  • Dec 2018
Rainwater harvesting (RWH) is the most economic and sustainable management method utilized to overcome the problem of water penury in arid regions. Jordan is one of the countries in the Middle East most suffering from water deficit since more than 80% of the country’s area receives 50-150 mm of annual rainfall. Different water harvesting techniques (WHT) have been used in many countries in arid and semi-arid regions. An evaluation experiment was conducted at two sites; one is at Al Mwaqar, southeast of Amman, and the other is at Al Grain, west of Al Azraq city. The objective of the current research is to evaluate and determine the effectiveness of two water harvesting techniques constructed by the common Vallerani system using continuous contour ridges and intermittent trenches (bunds) upon effective rainfall (runoff) affected by different land slopes, contour ridges spacing, and water harvesting structures. The results indicated that RWH increases water storage in planted area by two to three, fold depending on land slope and the contour ridges space, but with no significant differences between the applied WHT. Runoff amount increases with the increase of slope gradient (more than 5%), especially in small ridges space, which has shown the highest seasonal runoff range from 300 to 362 m3 ha-1 at Al Mwaqar site and from 192 to 243.5 m3 ha-1 at Al Grain site. Regression results indicated that there is high coloration between rainfall storms and runoff amount for all treatments. The best regression trend line was obtained from continuous contour ridges CT1 and CT2 with R2 being 0.95 and 0.96, respectively, at Al Mwaqar site. At Al Grain site R2 for continuous contour ranges between 0 .70 and 0.76 compared to R2 which ranges from 0.80 to 0.93 for Vallerani intermittent trenches, due to the effect of rock fragments on the catchment surface in the continuous contour area.
View
Contrasting tillage effects on stored soil water, infiltration and evapotranspiration fluxes in a dryland rotation at two locations
Article
Full-text available
  • Mar 2019
  • SOIL TILL RES
There are significant uncertainties in partitioning growing season precipitation into the water balance components that determine water available for dryland crop yield across a range of environments and tillage practices. We evaluated profile soil water contents at a high temporal resolution during phases of a dryland wheat (Triticum aestivum L.) –sorghum (Sorghum bicolor L.) -fallow rotation under no tillage (NT) and stubble-mulch tillage (ST) management at Bushland, Texas and Tribune, Kansas to assess event-based soil water balance components. Cumulative infiltration and evaporation were estimated based on hourly changes in stored soil water using a water balance approach and a drainage model. Estimated deep drainage comprised a small proportion of the soil water budget averaging five percent of annual precipitation in Bushland. Tillage did not significantly influence cumulative infiltration during summer fallow and growing season periods at Bushland. In contrast, NT at the Tribune location exhibited significantly greater (P=0.023) cumulative infiltration compared to ST during the wheat fallow period just prior to sorghum planting. At both locations during summer fallow periods, NT was not more efficient in increasing stored soil water over that obtained with ST. Evaporation during summer fallow periods was more a function of the soil water content near the surface than the tillage practice. Effective infiltration expressed as a fraction of precipitation averaged 0.55 and 0.57 under NT and ST, respectively, at Bushland compared with 0.83 and 0.52 under NT and ST, respectively, at Tribune. Observations of effective infiltration elucidate historical results of the incremental sorghum grain yield response of NT over ST that averaged 12 percent at Bushland and 35 percent at Tribune. Partitioning of growing season precipitation to transpiration was insufficient in Bushland to generate yield increases under NT of similar magnitude to that observed in Tribune demonstrating that NT does not perform similarly across all environments.
View
Degraded versus restored rangeland state’s in Jordan – hillslope to small-catchment level implications on runoff and erosion
Conference Paper
Full-text available
  • Apr 2018
Over the past decades, migration, overgrazing and mismanagement transformed the Jordanian rangelands into degraded badlands. Almost bare and crusted soil surface conditions are interlinked with accelerated runoff, soil erosion and gullying. Immense restoration efforts are being conducted to counter-measure further degradation. Mechanized micro-Water Harvesting (WH) based plantation of shrub seedlings is among the most promising techniques for large-scale application. The tractor ploughed micro-catchments collect surface runoff and locally increase soil moisture, which boosts the out-planted seedlings’ growth and eventually leads to shrub patches, enhancing biodiversity and habitat quality. ‘Al Majidyya’ rangeland monitoring site near Amman, Jordan, provides the according monitoring data for the present rangeland transition-state study using Rangeland Hydrology and Erosion Model (RHEM). The study investigates surface runoff and erosion pattern of the three different rangeland states: the i) supposed baseline, based on literature recherché and community feedback, ii) the present degraded status, and iii) micro-WH based restored scenario, combining field observation and modeling. Hill-slope level RHEM modeling was performed for a long-term erosion risk assessment, and event based spatially distributed watershed simulations were conducted for various scenario’s landscape response investigation. Comparison of the water and sediment dynamics of the baseline, degraded and restored state add on knowledge for the sustainability assessment of the micro-WH based restoration approach.
View
Land degradation risk assessment for sustainable rangeland restoration in Jordan
Poster
Full-text available
  • Apr 2018
In Jordan, various methods for rangeland restoration are being applied and evaluated for their success in vegetation recovery, biodiversity or habitat quality enhancement. However, it is difficult to determine a prior the long-term sustainability given limited data available and that most assessments are subject to a wide range of assumptions associated with the erratic nature of rainfall and droughts. A novel approach was set up for a 43 hectare large revegetated watershed with native shrub seedlings, located in the central Badia, investigating the risk of land degradation through comparing the native baseline’s water and sediment dynamics with the actual (degraded) and the restored scenario. From hydrological viewpoint, and under the consideration that water and sediment fluxes are balanced in a native rangeland environment, land degradation may occur once the water and sediment yields (i.e. surface runoff and soil erosion) significantly change in a restored landscape. For setting up the different scenarios an intense field campaign was conducted facilitating collection of various biophysical data, community questionnaires and historical information in and around the target watershed investigating the degraded, restored and pre-degraded conditions. The risk assessment approach evaluated combines a short-term watershed (spatial) and a long-term hillslope (temporal) scenario assessment. The assessment provided feedback on the vulnerabilities of different watershed zones as well as the long-term trends and occurrence of severe erosion events. The investigation of the local rainstorms implications on water and soil resources, in terms of the magnitudes and the occurrence probabilities of surface runoff and erosion, provide insights on the resilience and the sustainability of the performed restoration effort. The study elucidates water and sediment related trade-offs and the advantages and limitations of the restoration in the context of encouraging long-term sustainability of restoring degraded Badia rangelands in central Jordan.
View
Restoring Degraded Rangelands in Jordan: Optimizing Mechanized Micro Water Harvesting Technique using Rangeland Hydrology and Erosion Model (RHEM)
Conference Paper
Full-text available
  • Jun 2017
Jordan’s rangelands, the so called Badia, home of the Bedouins, are threatened through a combination of over-exploitation of the ecosystem services and a changing climate towards drier seasons and highly erratic rainfalls. In the recent decades, the once productive grazing lands transformed into sparsely vegetated and crusted desert grounds not capable of retaining the sporadic rainwater within the landscape - and consequential surface runoff inevitably accelerates soil erosion and gullying. To counter-measure the imminent rangeland degradation the International Center for Agricultural Research in the Dry Areas (ICARDA) is investigating mechanized micro Water Harvesting (WH) based restoration technique using the Vallerani plow. This technique intermediately breaks up the crusted surface soil layers and hard pans to approximately 50cm depth. Thus, creating dispersed micro-catchments, well-protected and suitable for the plantation of shrub seedlings, supporting the initial vegetation growth and eventually leading to shrub-island evolvement over the landscape. However, optimum design, particularly the spacing between the WH plow lines, depend on various environmental conditions. In this research, Rangeland Hydrology and Erosion Model (RHEM) was used to assess degraded rangeland hydrological response to transparently suggest on WH layout optimized for the magnitudes and the occurrence probabilities of runoff, soil erosion and sediment accumulation affecting the storage capacity of the micro-catchments. The study combined physical based modeling and ground truthing through different runoff and sediment related experiments. Preliminary results demonstrate good potential of the RHEM-based WH design approach; case study results will be presented for the first time at the conference. Eventually, a fully developed rangeland assessment system will support transparent target area selection and sound WH design interlinked with a risk analysis approach that accounts for the variable environmental patterns of the Badia.
View
Climate Change Impacts on Surface Water Availability & Management of Jordan’s Zarqa River Basin
Conference Paper
Full-text available
  • Mar 2017
Zarqa River Basin (ZRB) is among Jordan’s most important surface water basins, hosting the country’s major cities and industry, and providing water for agricultural production within the basin and beyond. ZRB’s surface runoff dilutes the treated wastewater of Khirbat As-Samra plant, mainly discharged by Greater Amman’s and Zarqa’s wastewater, before reaching King Talal Dam and further downstream covering up irrigation water demands of the Jordan Valley. Due to deforestation, intensive agriculture and overgrazing large areas of ZRB became vulnerable to soil erosion and thus land degradation - whereas the eroded sediments of the basin eventually accumulate in King Talal Reservoir and consequently decrease the impoundment’s storage capacity. On top of this, the changing climate affects both quantity and the occurrence pattern of rainfall potentially speeding up land degradation and water storage loss of the King Talal Reservoir. A hydrological model was set up to better understand the spatial pattern of surface water affected by various Soil and Water Conservation (SWC) interventions within the basin and thus to reflect the landscape’s response to 1) actual, as well as 2) future climatic conditions. Therefore, different Representative Concentration Pathway (RCP) scenarios of Global Circulation Models (GCMs) were simulated to assess the predicted changes of rainfall and temperature. This contributes to the evaluation of future surface water availability - to increase preparedness for the predicted climatic changes and to support the development of mitigation strategies align with the Jordanian water sector management plans.
View
Legal Liability for Environmental Damage: The United Nations Compensation Commission and the 1990-1991 Gulf War
Chapter
Full-text available
  • Nov 2016
The United Nations Compensation Commission (UNCC) proved to be an innovative institution that implemented a law- based approach to the transition from conflict to peace and to the restoration of war-damaged environmental resources. This chapter illustrates how the UNCC adapted the traditional bilateral compensation commission model to address the substantial environmental damage that resulted from the 1990–1991 Gulf War. The goal of the chapter is to provide guidance for similar occurrences in the future. Conflict over shared oil deposits led Iraq and Kuwait into war. The dispute was notable for the extent to which natural resources played a role: in addition to serving as a pretext for war, natural resources had been both the instruments and victims of aggression. Iraq’s invasion of Kuwait violated the general principles of international law (specifically, the prohibition of aggressive war) and the treaty obligations that Iraq assumed when it joined the UN. Under international law, a nation that breaches certain obligations may be obligated to pay financial compensation in reparation for the damage it has caused. Exercising its authority under chapter VII of the UN Charter, the Security Council established a subsidiary body, the UN Compensation Commission (UNCC), to provide financial compensation for losses caused by Iraq’s illegal actions. The commission reviewed over 2.6 million claims from individuals, corporations, international organizations, and governments seeking a total of approximately US$352 billion in compensation; the claimed losses included the cost of extinguishing the oil well fires, and environmental harm. More than US$52 billion has been awarded to successful claimants from more than 100 nations and international organizations. As of April 2014, US$45.5 billion had been paid for distribution to successful claimants, and only one Kuwaiti claim remained with an outstanding balance. In the broader context of international law, compensation serves as a nonpunitive deterrent that provides a remedy to victims. The Security Council’s decision to include compensation for pure environmental losses was a new step in international law. The UNCC demonstrates that states can be held accountable for wartime environmental damage, and reveals the benefits that can be obtained from multi- lateral engagement and long-term commitment to environmental restoration. The chapter is divided into five major sections: (1) a discussion of the conflict that ultimately led to the establishment of the UNCC, with a particular focus on the role of natural resources in Iraq’s decision to invade Kuwait and the resulting environmental damage; (2) a description of the establishment of the UNCC; (3) a consideration of the legal procedures and principles that shaped the work of the UNCC, including the review of environmental claims; (4) an assessment of the UNCC as an instrument of reparations and post-conflict restoration; and (5) a brief conclusion.
View
Predicting micro-catchment infiltration dynamics
Article
  • Mar 2020
  • CATENA
Rainfall and concentrated flow experiments were carried out on seven micro-catchments (MCs) that were designed to limit soil erosion and allow for water-harvesting. Prediction of infiltration rates within MCs is necessary to design effective hillslope-scale restoration projects. Continuous stage measurements and 3-D models of MC geometry were used to calculate infiltration rates from field experiments. Soil samples and Guelph permeameter (GP) measurements were collected to parameterize a predictive infiltration model in Hydrus 2D/3D. The model result of water velocity into the soil profile was averaged by depth intervals and multiplied by the corresponding MC surface area to calculate a volumetric flow rate. Four parameterizations of changes in conductivity with depth were evaluated within the model framework to determine which would best account for spatial heterogeneity. Use of the maximum field-measured conductivity provided the least biased results, with average error between simulated and measured values across all sites of less than 1%. Model results illustrate the limitations associated with particle-size distribution or GP measurements when used to predict infiltration rates in a numerical model. GP measurements with single ponded heights allowed convenient field measurement of conductivity that worked better than predictions from soil texture. The maximum of several GP samples was more representative of MC infiltration than the mean, so a higher percentile value from a distribution of MC measurements may help to account for complex infiltration processes that are not included in numerical models. This modeling approach will allow testing of process-based hypotheses about rangeland infiltration dynamics, and the development of optimal configurations of MCs at sites being considered for rangeland restoration.
View
Impact of stone bunds on temporal and spatial variability of soil physical properties: A field study from northern Ethiopia
Article
  • Jan 2018
In the Ethiopian Highlands, stone bunds are a common practice for soil and water conservation, influencing runoff and erosion processes from sloped agricultural areas. The objective of this study was to investigate how stone bunds affect spatio-temporal relationships of these processes to better understand their impacts on soil water development at the smallholder farmer's field level. Study area was the Gumara-Maksegnit Watershed in Northern Ethiopia, where two representative transects were investigated: One transect crossed a 71 m long field intersected by two stone bunds (SB) traced along the contour. The second transect crossed a similar hillslope without conservation structures at a length of 55 m representing baseline (untreated) conditions (NSB). During the rainy season 2012, bulk density, volumetric water content were monitored as well as tension disc infiltrometer experiments were performed to determine the saturated hydraulic conductivity and to derive soil water retention characteristics. Our observations show that SB decreased significantly soil bulk density in center and lower zones of SB transect compared to NSB. No temporal change was observed. Results targeting the surface soil moisture indicate that infiltration was higher with SB and happened earlier in the rainy season in the zones around the SB. Saturated hydraulic conductivity was positively affected by SB and increased significantly. Improved soil hydrology by SB fields may increase crop yields by higher soil water contents but also by extending the growing season after the rainy season. Therefore, stone bunds are a successful measure to establish climate-resilient agriculture in the Ethiopian highlands.
View