Soil Conservation Practices Research Articles

Spatial-Temporal Response of Sediment Loads to Climate Change and Soil Conservation Practices in the Northern Aegean Watershed, Türkiye

Climate change and agricultural activities are significant sources of stress to the natural environment and water resources. These also affect erosion and the associated estimation of sediment yields, which is also a crucial task in the hydrological models. The presented study is significant for the development of sustainable watershed management practices. It also aims to determine the effects of climate change and different agricultural best management practices (BMPs) on the sediment loads of the North Aegean Basin in Türkiye by using the Soil and Water Assessment Tool (SWAT) model. While sediment calibration was performed for 2014, streamflow calibration and verification were performed using the SWAT Calibration and Uncertainty Program (SWAT-CUP) for the period 2012–2013 and 2014–2015, respectively. The obtained results showed that the climate change scenarios reduce the surface waters of the basin and sediment yield in accordance with the hydrological transport processes. During the 2012–2030 time period, runoff in the basin for the RCP4.5 and RCP8.5 climate change scenarios decreased by 38.5% and 31.8%, respectively, and the basin sediment yield decreased by 55.7% and 50.7%, respectively. The sediment yields to water resources had distinctive reductions due to BMPs such as zero tillage, vertical tillage, cover crop, and terracing. Considering the RCP4.5 and RCP8.5 scenarios, BMPs reduced the sediment yield in the range of 0.93–4.03% and 0.89–3.85%, respectively. Determining the sediment transport by using hydrological modeling and the effects of climate change for different agricultural practices on erosion will be useful for decision-makers.

Effects of soil and water conservation practices and landscape position on soil physicochemical properties in Anuwa watershed, Southern Ethiopia

Ethiopia's main environmental problem has been soil erosion. To control and reverse the problem, soil and water conservation (SWC) techniques have been deployed over the past two to three decades. The purpose of this study is to evaluate the effect of implemented soil and water conservation measures on soil physicochemical properties in the Anuwa watershed, southern Ethiopia, under various conservation structures (Soil bund, Fanya Juu, Stone bund and Micro Basin) and topographic positions (upper, middle and lower) of conserved plots. The soil samples were collected from 45 locations to analyze topsoil texture, bulk density (ρd), pH, soil organic carbon (SOC), total nitrogen (TN), available phosphorus (AP), CEC, exchangeable Na+, K+, Ca2+, and Mg2+. All soil samples were analyzed using standard and recommended methods. Using the SPSS computer program 21, the effect of independent variables (SWC practices and landscape position) on the dependent variables (soil properties) was statistically tested. The significance test was performed using two-way ANOVA. The findings indicated that the SWC measure significantly decreases the percent values of sandy soil texture, while it increased the mean values of organic carbon, available phosphorus, exchangeable Na+, K+, Ca2+, Mg2+, and CEC (P < 0.05). The sand content, the bulk density, the SOC, and the total nitrogen showed statistically significant variations between the conserved and non-conserved upper topography (P < 0.05). The effects of conservation measures were significant in almost all soil physicochemical properties at P < 0.01 except for the silt content, bulk density, and Ca2+ in the lower topography. The study findings revealed that Fanya Juu SWC measures are by far the most efficient, and recommended method to minimizing soil erosion, and improving selected soil physical and chemical quality in the Anuwa watershed. Local governments and other stakeholders should work cooperatively to strengthen and sustain the implementation process.

Substantially Enhanced Landscape Carbon Sink Due To Reduced Terrestrial‐Aquatic Carbon Transfer Through Soil Conservation in the Chinese Loess Plateau

AbstractSoil conservation is of global importance, as accelerated soil erosion by human activity is a primary threat to ecosystem viability. However, the significance and role of soil conservation in reshaping landscape carbon (C) accounting has not been comprehensively integrated in the terrestrial C sink. Here, we present the first integrated assessment of the modified terrestrial C sink and aquatic C transport due to soil conservation for the semiarid Chinese Loess Plateau (CLP), the world's most vulnerable region to soil erosion. We show a surprisingly low terrestrial‐aquatic C transfer that offset the terrestrial net ecosystem productivity by only 7.5%, which we attribute to the effective implementation of soil conservation practices. Despite the highest soil erosion, the semiarid CLP acts as effective C sink at 43.2 ± 22.6 g C m−2 year−1, which is comparable to temperate forest in absorbing atmospheric CO2. Moreover, C burial in reservoirs has created an additional anthropogenic C sink of 2.9 ± 1.1 g C m−2 year−1. Our findings indicate that effective soil conservation can significantly increase landscape C sequestration capacity. The co‐benefits of soil conservation in erosion control and C sequestration have important implications for policy makers in other regions undergoing increasing erosion intensity to pursue environmental sustainability.

LULC dynamics and application of nature based solution in high erosion prone areas of Malappuram District

Kerala State is highly vulnerable to natural disasters, mainly soil erosion due to changing climatic dynamics in the steep slope. In 2018 and 2019 flood, some districts in Kerala State were affected by significant floods due to extreme and prolonged rainfall, leads to large and small landslides. Malappuram is one of the districts that got affected in 2018 and 2019 flood. Disaster risks are augmented by a critical factor that has been silently rising in the State now, which is change in the land use pattern and practices. Hence, the Land Use and Land Cover Dynamics study was conducted in the selected watersheds (Kakkarathode – Pulikkal and Palathingal) of Malappuram district, and spotted major landslides in the area. The LULC dynamics were carried out in the different time periods like 2013, 2018 and 2020. LISS IV (5.8 m resolution) satellite images were used for the analysis and field visit, to identify the related changes. Accuracy of the classification was evaluated using error matrices and kappa statistics. The overall accuracies for 2013, 2018 and 2020 were 84.93%, 86.21% and 87.5% respectively and the corresponding Kappa values were 0.82, 0.84 and 0.85 which indicates the high accuracy of the classification. The flood has mainly affected Plantation, Paddy and Mixed Plantation which had been decreased during 2018-20 and has resulted in the emergence of more Barren land and Waste Land. LULC helps in identifying the changes in the erosion prone areas. Moreover, erosion hazardous area and its prioritization in applying the soil management and conservation practices can be effectively done using LULC change assessment. Nature based solutions such as planting trees and grasses (like shrubs, vetiver grass etc.), construction of ponds, creation of green walls and assemblage of vegetations can be adopted in the region of high-risk hazardous area depending on the categorized zone.

ANALYSIS OF CONSTRAINING FACTORS REGARDING ADOPTION OF SOIL AND WATER CONSERVATION PRACTICES IN THE POTHOHAR, PUNJAB

The current study was conducted at Institute of Agri. Extension, Education and Rural Development, University of Agriculture, Faisalabad in 2022. Rawalpindi district was selected purposively as it receives maximum rainfall. Four out of seven tehsils of Rawalpindi were selected purposively based on maximum numbers of farmers. A sample size of 381 respondents was drawn using surveysystem.com. Proportionate sampling technique was used to interview 214, 104, 32 and 31 farmers from tehsil Gujar Khan, Rawalpindi, Kotli Satiyan and Kahuta respectively. Mix methods research design was used to conduct the study. Quantitative and qualitative data were collected using well-structured interview schedule and a comprehensive interview guide respectively. Research findings revealed that awareness and adoption level of farmers regarding various soil and water conservation practices was unsatisfactory. High level adoption gap was found regarding different soil and water conservation practices: crop rotation (92.4%), intercropping (99.7%), cover cropping (99.8%), terracing (96.1%), broad bed and furrow system of land configuration (96.6%), sowing drought resistant varieties (86.3%), contour farming (85%) and mulching (97.9%). It was concluded that farmers were not only deprived of the advisory services but also the required trainings and technical assistance regarding adoption of conservation measures. Therefore, provision of trainings and demonstration facilities were strongly recommended to educate the farmers regarding basic soil and water conservation measures. Moreover, farmers should also be provided with financial assistance in form of subsidized input supply.

Environmental potential for crop production and tenure regime influence fertilizer application and soil nutrient mining in soybean and maize crops

CONTEXTDifferences in land tenure regimes are one challenge to implementing soil conservation practices in agricultural systems. It is frequently assumed that tenants are less likely to adopt soil conservation strategies than owners, given a shorter-term engagement with the field. Also, the field's environmental potential (i.e., potential for agricultural production) may influence farmers' investment decisions, since high-potential fields increase the chances of achieving a return on the investment. OBJECTIVEUnderstand the effect of land tenure regimes and environmental potential on fertilization rates and balance of nitrogen, phosphorus, and sulfur in soybean and maize crops in Argentina. METHODSWe applied mixed-effects models on a database of 52,588 fields of soybean and maize farms, covering a total area of 3.8 M ha in Argentina during the period of 2017–2022. RESULTS AND CONCLUSIONSOverall, the balance of nitrogen, phosphorus, and sulfur was (mean ± SE) −29.11 ± 0.15, −2.58 ± 0.38, and 8.26 ± 0.044 kg ha−1 yr−1, respectively. Despite 8.04 and 0.63 kg ha−1 yr−1 more nitrogen and phosphorus were applied in high-potential compared to low-potential maize fields, nutrient outputs were still higher. Therefore, net nutrient exports of the most productive fields increased by 9.99 and 2.06 kg ha−1 yr−1 for nitrogen and phosphorus, respectively. In soybean fields, environmental potential had no effect on nutrient application, but the net export of nitrogen and phosphorus was 9.85 and 2.14 kg ha−1 yr−1 higher in high-potential fields compared to low-potential fields. Tenure regime had a weak effect, mainly on phosphorus. On average, owners applied 0.37 kg ha−1 yr−1 more and exported 0.28 kg ha−1 yr−1 less phosphorus than tenants in both crops. Sulfur application and balance were weakly affected by the studied variables, and the positive balance suggests overfertilization under the assumptions of this paper. We conclude that the Argentine farming system depletes some of the main nutrients, regardless of the field's environmental potential or the land tenure system. The effect of the tenure regime is overwhelmed by the impact of environmental potential on farmers' fertilization management, with high-potential fields degrading due to soil mining at a faster pace than low-potential fields, putting future yields at risk. SIGNIFICANCEBy exploring a farming system based on nutrient depletion, our results contribute to the general understanding of tenure regime consequences on soil degradation. Argentinean farmers should consider increasing N and P application and contemplate environmental heterogeneity to avoid nutrient mining and degradation of one of the most productive areas of the world.

Multi-temporal spatial modelling to assess runoff and sediment dynamics under different microtopographic patterns

Soil erosion is a multi-scale geographical interface process with high spatiotemporal variability. This study aimed to assess runoff and sediment dynamics under different microtopographic patterns based on wavelet analysis and SIMulated Water Erosion model (SIMWE). Three rainfall intensities of 1.0 mm min−1, 1.5 mm min−1, and 2.0 mm min−1, combined with three slope gradients of 10°, 15°, and 20°, were utilized to conduct rainfall simulations on three soil boxes measuring 4 m in length and 0.8 m in width. The soil boxes exhibited distinct microtopographic patterns, including smooth slope (CK), artificial digging (AD), and ridge tillage (RT). The results showed that the runoff and sediment reduction benefits of different tilled slopes decreased with an increase in both slope and rainfall intensity. The AD and RT slopes reduced runoff yields by 8.4% − 50.2% and 17.3% − 75.0% respectively compared to CK slope. Although sediment yields from AD and RT slopes were reduced by 4.2% − 51.6% and 1.8% − 53.0%, respectively, the sediment control benefits of AD and RT slopes were basically lost when the slope gradient increased to 20°. The rill erosion was the main source of soil erosion on different tilled slopes, accounting for 72% − 87% of the total soil loss. And the rates of both soil erosion and rill erosion exhibited a power function relationship with an increase in rainfall intensity and slope. The impact of slope gradient on soil erosion on the RT slope was greater than those on the CK and AD slopes. During the development of rill erosion, non-stationary and multi-scale periodic phenomena exist in the time series of runoff and sediment on different microreliefs. As surface microrelief increased, the fluctuations in runoff and sediment on tilled slopes intensified, resulting in a gradual shortening of the variation period. And this study verified the feasibility of the SIMWE model to simulate the runoff and sediment dynamics on microtopographic scale under a single rainfall event. The results can provide a theoretical basis for the scientific layout of soil and water conservation practices in sloping farmland and the construction of soil erosion model in purple soil area.

Global Analysis of the Cover-Management Factor for Soil Erosion Modeling

Land use and management practices (LUMPs) play a critical role in regulating soil loss. The cover-management factor (C-factor) in Universal Soil Loss Equation (USLE)-type models is an important parameter for quantifying the effects of LUMPs on soil erosion. However, accurately determining the C-factor, particularly for large-scale assessments using USLE-type models, remains challenging. This study aims to address this gap by analyzing and comparing the methods used for C-factor quantification in 946 published articles, providing insights into their strengths and weaknesses. Through our analysis, we identified six main categories of methods for C-factor quantification in USLE-type modeling. Many studies have relied on empirical C-factor values for different land-use types or calculated C-factor values based on vegetation indices (VIs) in large study areas (&gt;100 km2). However, we found that no single method could robustly estimate C-factor values for large-scale studies. For small-scale investigations, conducting experiments or consulting the existing literature proved to be more feasible. In the context of large-scale studies, employing methods based on VIs for C-factor quantification can enhance our understanding of the relationship between vegetation changes and soil erosion potential, particularly when considering spatial and spatiotemporal variations. For the global scale, we recommend the combined use of different equations. We suggest further efforts to develop C-factor datasets at large scales by synthesizing field-level experiment data and combining high-resolution satellite imagery. These efforts will facilitate the development of effective soil conservation practices, ensuring sustainable land use and environmental protection.

Residual effects of pipeline construction on agricultural soils of the Canadian prairie

AbstractThe return to equivalent capability was evaluated on a &gt;1000 km oil and gas pipeline corridor on the western Canadian prairies. Resource constraints limited this first phase of sampling to soils more likely damaged by disturbance. Three pipelines were selected to span a 55‐year period of construction. Data were collected from four transects established within each of six randomly chosen quarter sections (each 65 hectares) that included reference sites. Laboratory analysis provided data for organic carbon, pH, calcium carbonate equivalent, sodicity, salinity, and particle size distribution. Field procedures were used to obtain data for topsoil thickness, bulk density, aggregate size distribution, and carbonate distribution. The Canadian Land Suitability Rating System was employed to evaluate and compare the land capability (LSRS rating) of three pipelines to that of adjacent reference capability. Pipeline‐reference differences were detected in the topsoil for soil organic carbon (83% of reference), calcium carbonate equivalent (62% higher), and pH (0.4 units higher), and in the subsoil for bulk density (2% higher) and electrical conductivity (a fivefold increase). Carbonates were observed more frequently on the pipelines than on references. Soil organic carbon increased and electrical conductivity decreased with time since construction. The mode of land capability was class 4 on the corridor and class 3 on references. Residual effects remained. Neither soil conservation and reclamation practices, nor natural recovery had yet achieved equivalent capability for the target soil group, representing 17% of the extent of the corridor.

Overcoming agricultural sustainability challenges in water-limited environments through soil health and water conservation: insights from the Ogallala Aquifer Region, USA

ABSTRACTA rapid decline in water availability for crop production has driven substantial changes in cropping systems in the arid and semi-arid regions, including transitions from irrigated to dryland cropping. Management decisions play a critical role in the sustainability of agricultural systems facing transitions. Specifically, adopting practices that increase crop water use efficiency, improve soil health, and conserve water in the soil profile could improve agricultural sustainability. This review discusses published literature on the challenges associated with crop production and highlights management strategies to sustain soil health, enhance agricultural production, and farm profitability in the Ogallala Aquifer region to elucidate pathways to agricultural sustainability in water-limited environments around the world. We searched for published papers discussing soil health and water conservation practices, including conservation tillage, crop residue management, crop diversification, cover cropping, and livestock integration in cropping systems. These studies demonstrate adopting conservation systems can increase soil organic carbon (SOC) storage, water infiltration, soil microbial activities, water use efficiency, and decrease N fertilizer inputs compared to conventional systems. Integrating more than one soil and water conservation practice can complement to enhance soil health and sustainability of dryland or limited-irrigation agriculture in the Ogallala Aquifer region and similar agroecosystems across the world.

Effects of fresh and field-aged holm-oak biochar on As, Cd and Pb bioaccumulation in different rice growing environments

Arsenic, Cd, and Pb environmental fate is influenced when the traditional permanent flooding rice production systems are replaced by water-saving and soil conservation practices, urging for additional strategies that avoid their bioaccumulation in rice grain. The aim of this two-years field study was to evaluate the effects of fresh and field-aged biochar on As, Cd, and Pb bioaccumulation, and on As speciation, in rice grain produced in different growing environments (flooding versus sprinkler and conventional tillage versus direct seeding). Biochar produced from holm-oak pruning residues (pyrolysis at 550 °C, 48 h), in a single application (28 Mg ha−1), reduced As bioaccumulation in rice grain in the permanent flooding system to non-quantifiable concentrations (e.g., from 0.178 mg kg−1 to <0.04 mg kg−1, for inorganic-As, respectively), an effect which remained under field-aging conditions, increasing rice commercial value. When adopting sprinkler irrigation, the undesirable increase in Cd bioaccumulation in rice, relatively to the anaerobic system, was counteracted by biochar application, reducing its bioaccumulation in kernels between 32 and 80 %, allowing a simultaneous control of metals and metalloids bioaccumulation in rice. The bioaccumulation of Pb was also prevented with biochar application, with a reduction in its concentration four- to 13-times, in all the management systems, relatively to the non-amended plots, under fresh biochar effects. However, Pb immobilization decreased with biochar field-aging, indicating that the biochar application may have to be repeated to maintain the same beneficial effect. Therefore, the present study shows that the implementation of sprinkler irrigation with holm-oak biochar could reduce the risk of heavy metals(loids) bioaccumulation in rice grains and, thereby, ensuring food safety aspects, particularly under fresh biochar effects.

Study of Physio-chemical Properties of Soil in Various Land Use Systems of Krishna District, Andhra Pradesh, India

A study was carried out to evaluate the impact of various land use systems on the physiochemical characteristics of the soil of Krishna District, Andhra Pradesh. The samples were collected from various land use systems (normally cultivated land, plantation, forest, fruit and vegetable) at two different depths (0-15 cm and 15-30 cm) and analysed at the Soil Science - Soil and Water Conservation Laboratory at the Rajiv Gandhi South Campus, Banaras Hindu University, Barkachha, Uttar Pradesh. Geographically, the experimental site is located under the tropical zone at the coordinates of 16.4° N and 81.0° E. The obtained results showed that the maximum bulk density (1.58 Mg/m3), particle density (2.7 Mg/m3) at lower depth of 15-30 cm, water holding capacity (49.70%) and highest porosity (48.68%) in upper soil layer (0-15 cm) in normally cultivation land. Forest land had showed the highest organic carbon content of 0.77% and 0.71% soil in two different study depths of 0-15 cm and 15-30 cm, respectively. Also, the maximum availability of nitrogen (280.17 kg/ha), phosphorus (18.63 kg/ha), potassium (212.65 kg/ha) and sulphur (8.64 mg/kg of soil) were reported in forest, Vegetable, fruit and cultivated land respectively, in upper soil layer (0-15 cm), also all were found to depleting with increasing soil depths. The results of this study showed that land use patterns had considerable impact on many soil physiochemical properties. This study have a great importance for improving the standard of the produce, raising crop yields by a greater percentage through nutrient management, appropriate soil conservation practices and also, for better prevention of the environment.

Assessment and Documentation of Indigenous and Introduced Soil and Water Conservation Measures in Some Parts of Southern Ethiopia

In Ethiopia, soil and water conservation (SWC) activities were initiated after the famines of 1973 and 1985. Subsequently, various conservation measures were implemented by the government and non-governmental organizations to improve sustainable agricultural production. This study was designed to identify, measure, and describe indigenous and introduced soil and water conservation practices in four zones of Southern Ethiopia, namely Wolaita, Hadiya, Kambata Tambaro, and Dawro. It was found that biological, physical, and agronomic measures were implemented in the study area. However, the technical evaluation results reveal that certain practices, such as traditional cutoff drain, fanya juu, soil bund, stone-faced soil bund, brushwood, and gabion check-dams face technical, social, and institutional challenges. The results also indicate that less attention has been given to indigenous SWC practices by different stakeholders including government organizations (GOs), non-governmental organizations (NGOs), and research institutes. As a result, their respective dimensions were not modified, effective measures were not upscaled, and circulated to other areas with similar agroecology and farming systems. In general, farmers in the study area are well acquainted with soil erosion, its causes, and the consequent reduction in land productivity. The results of our research will undoubtedly aid in identifying and documenting the practices that have been identified for future reference.

A scenario modelling approach to assess management impacts on soil erosion in coffee systems in Central America

Soil erosion is one of the major causes of soil degradation worldwide, because it causes the depletion of soil organic carbon, nutrients, and water holding capacity. In Central America, coffee production is vulnerable to soil erosion since it often occupies steep slopes with high annual precipitation. To assess management options to control erosion, soil and vegetation field data were collected from 90 Costa Rican and 96 Guatemalan coffee plantations, mainly shaded, distributed in six coffee production areas. Soil erosion was modelled using the RUSLE (Revised Universal Soil Loss Equation), integrating soil and vegetation cover field data, with remote sensing data. Management scenarios were developed to assess the role of two principal coffee management strategies in mitigating soil erosion: increasing vegetation cover, and soil conservation practices. Average estimated erosion rates of 17 and 7 Mg ha−1 yr−1 were predicted for plantations of Costa Rica and Guatemala, respectively, with erosion from coffee plantations representing between 23% and 40% of the estimated erosion of the watershed within which they were situated. If all plantations achieved vegetation cover equivalent to the best 25% of plantations, the estimated erosion would be reduced by 7% in Costa Rica and 8% in Guatemala. If all plantations implemented soil conservation practices, estimated erosion would be reduced by 11% in Costa Rica and 35% in Guatemala. With the two combined management strategies a reduction of estimated erosion of 17% and 40% was predicted in Costa Rica and Guatemala, respectively. The reduction in erosion from soil conservation or better vegetative cover varied among regions within countries depending on current management, local climate, and topography. These results show the importance of coffee system and soil management practices in moderating erosion from highland coffee production, and how RUSLE analyses can identify priority practices in different regions supporting more effective policies to reduce soil erosion.

Quantitative Evaluation of Soil Water and Wind Erosion Rates in Pakistan

Soil erosion triggered by water and wind pose a great threat to the sustainable development of Pakistan. In this study, a combination of geographic information systems (GISs) and machine learning approaches were used to predict soil water erosion rates. The Revised Wind Erosion Equation (RWEQ) model was used to evaluate soil wind erosion, map erosion factors, and analyze the soil erosion rates for each land use type. Finally, the maps of soil water and wind erosion were spatially integrated to identify erosion risk regions and recommend land use management in Pakistan. According to our estimates, the Potohar Plateau and its surrounding regions were mostly impacted by water erosion and have a soil erosion rate of 2500–5000 t·km−2·a−1; on the other hand, wind erosion predominated the Kharan Desert and the Thar Desert, with a soil erosion rate exceeding 15,000 t·km−2·a−1. The Sulaiman and Kirthar Mountain Ranges were susceptible to wind–water compound erosion, which was more than 8000 t·km−2·a−1. This study offers new perspectives on the geographic pattern of individual and integrated water–wind erosion threats in Pakistan and provides high-precision data and a scientific foundation for designing rational soil and water conservation practices.

Farmers’ perceptions of climate variability and adaptation strategies in the rural areas of Dire Dawa administration, eastern Ethiopia

Climate variability has significant impact on agricultural production especially in low-income countries where agriculture largely relies on rainfall, but only a few studies explored this issue at local scale. Therefore, this study was conducted to characterize local climate and assess farmers' perceptions and adaptation strategies to climate variability in the rural areas of Dire Dawa administration. Historical rainfall and temperature data (1987–2017) were obtained from National Meteorological Agency (NMA) of Ethiopia, while data of farmers' perceptions and adaptation strategies were collected from a total of 120 household heads through survey questionnaire, key informant interviews and focus group discussions. The results revealed that the area received an average annual rainfall of 568.3 mm with main rainy season (kiremt) contributing 70.7% to annual rainfall. The earliest and latest onset dates of kiremt season were 15th of April and 2nd of August, respectively. The amount of annual and kiremt rainfall totals showed low and medium variability with a coefficient variability (CV) of 18.3% and 27.7%, respectively, whereas short rainy season (belg) rainfall had high variability with a CV of 43.9%. Climate variability perception analysis showed that an overwhelming majority of the respondents (90%) perceived a decrease in the annual rainfall and 91.7% detected an increase in annual average temperature in the study area. Farmers of the study area were well aware of the changes in rainfall and temperature and thus employed a range of adaptation practices. Soil and water conservation practices (100%), off-farm income diversification (63%), planting drought-tolerant varieties (50%) and changing of planting date (45%) were the main adaptation strategies employed in the study area to avert the negative effects of climate variability. The findings imply that the area has been experiencing palpable changes in climate variables during the study period against which farmers exercised multiple adaptation strategies. However, farmers in the area are still face hardship as a result of climate variability which necessitates improving farmers’ resilience through innovative mechanisms and better extension services.

Intra-household risk perceptions and climate change adaptation in sub-Saharan Africa

Abstract We examine the effects of spouses’ climate risk perceptions (CRPs), defined by their beliefs about unfavourable climatic events and associated damages, on climate change adaptation (CCA) and the observed gender gap in adaptation. Our analysis uses the intra-household data collected by independent interviews with 1,274 female and male spouses in Kenya, Uganda and Senegal. By addressing the CRP endogeneity issue using the exogenous weather shocks during data collection months as instruments, we find that a higher CRP of both female and male spouses increases their probability of adopting CCA strategies. We also find that a higher CRP of female spouses reduces the adaptation gap by increasing their relative adoption of soil and water conservation practices. Our results highlight the importance of understanding gender-differentiated behavioural and economic factors to design effective climate policy interventions.

Effect of tillage systems combined with plastic film mulches and fertilizers on soil physical properties in a wheat-agricultural site in southern Iraq

This study researches the influence of the three tillage systems (conventional, economical and mulch tillage) when combined with different soil plastic mulching and fertilizer applications on key selected soil physical properties (SPP) at 0-20 cm soil depth in a wheat agricultural site, during summer (from 1st June to 31st July 2015). SPP include soil porosity (Φ), volumetric soil water content 60 days after irrigation to field capacity (q60), and mean weight diameter of aggregates (MWD). The term mulch tillage refers here to a soil conservation practice where the soil surface is disturbed by tillage whereby crop residues are mixed with the soil and a certain amount of residues remain on the soil surface, while mulching refers to the placement of inorganic material over the top of a soil surface to protect it. Soil treatments included tillage system: conventional tillage using a combination of a mouldboard plough and a disc harrow (MP+DH), economical tillage using a rotary cultivator (RC), and mulch tillage using a chisel plough (MT+CP); soil plastic mulching: transparent mulching (TM), black mulching (BM) of 200 cm wide with 0.05 cm thick, and without mulching (WM); and fertilisers: composed organic fertiliser (CoF), no-composed organic fertiliser (NoF), and chemical fertiliser (ChF). The split–split-plot design under the randomized complete block design (RCBD) was established in 27 treatments with 3 replicated, to map Φ, q60, and MWD based on 81 soil samples from all treatments. Results showed that the different soil treatments have diverse impacts on SPP. MP+DH resulted in the higher q60 (0.22 cm3 cm-3), MWD (0.85 mm), and Φ (56.87%). Our findings showed that MT+CP obtained a higher MWD of 0.98 mm and lower Φ of 49% compared to other tillage systems. Soil mulching had significantly modified SPP, with BM resulting in the highest Φ (55.65%), q60 (0.35 cm3 cm-3), and MWD (1.06 mm). Results indicated no significant differences between fertiliser types on SPP. The CoF had a significant effect on MWD and related soil characteristics studied. These findings can help us to understand the individual and combined effects of the tillage system, mulching, and fertilization application on some soil characteristics in wheat agriculture. A further study with more focus on the influence of tillage depths and mulching types (plastic vs organic mulch for different crops) under a variety of soils and climatic conditions, as well as on soil thermal properties needs further investigation.

Soil Erosion Status Prediction Using a Novel Random Forest Model Optimized by Random Search Method

Soil erosion, the degradation of the earth’s surface through the removal of soil particles, occurs in three phases: dislocation, transport, and deposition. Factors such as soil type, assembly, infiltration, and land cover influence the velocity of soil erosion. Soil erosion can result in soil loss in some areas and soil deposition in others. In this paper, we proposed the Random Search-Random Forest (RS-RF) model, which combines random search optimization with the Random Forest algorithm, for soil erosion prediction. This model helps to better understand and predict soil erosion dynamics, supporting informed decisions for soil conservation and land management practices. This study utilized a dataset comprising 236 instances with 11 features. The target feature’s class label indicates erosion (1) or non-erosion (−1). To assess the effectiveness of the classification techniques employed, six evaluation metrics, including accuracy, Matthews Correlation Coefficient (MCC), F1-score, precision, recall, and Area Under the Receiver Operating Characteristic Curve (AUC), were computed. The experimental findings illustrated that the RS-RF model achieved the best outcomes when compared with other machine learning techniques and previous studies using the same dataset with an accuracy rate of 97.4%.

Analyzing the influence of changes in land use and management practices on the lag time of peak flows for tropical watersheds of Ethiopia

AbstractChanges in peak flow response time governed by rainfall and physical configurations of watersheds have been the topic of many studies, but other factors are also important. We aimed to analyze the dynamics in the lag time (TL) of peak flow for a tropical watershed (Kecha) and its sub‐watersheds (Dokmit, Zenjero Maderia, and Wotit Minch) in Ethiopia, as influenced by land‐use changes from 1982 to 2017 and the implementation of soil and water conservation (SWC) practices since 2011. Layered maps of land use, soil type, and SWC practices were used to determine the curve number, and the Natural Resource Conservation Service hydrologic model was used to estimate TL. We compared the estimated values against measured median values of TL for 30 rainfall–runoff events. The estimated TL of 1982, 2005, and 2017 varied from 9 to 19 min, 8 to 18 min, and 10 to 22 min, respectively, in the Dokmit, Zenjero Maderia, and Wotit Minch sub‐watersheds. The smallest (8 min) and greatest (22 min) values of TL were observed during 2005 and 2017, respectively. These results are likely attributable to the increased amount of cultivated area at the expense of bushland and forest in 2005 as compared to 1982, and the implementation of SWC practices in 2011–2017. Dokmit had the lowest TL values of the three sub‐watersheds, most likely because of its greater coverage of grazing and cultivated lands and degraded Nitic Luvisol. The variation in TL values among the sub‐watersheds was related to changes in both land use and SWC practices but also to the presence of degraded areas inherited from past human activities. Overall, such spatiotemporal flow response time analysis can provide useful information for the proper design of sustainable development strategies for particular niches in tropical regions of Ethiopia and elsewhere.