Soil Conservation Practices Research Articles

Effect of biochar and attapulgite amendment on saline soil hydraulic parameters and shrinkage

AbstractSaline soil reduces soil productivity and exacerbates food security problem. Therefore, it is increasingly necessary to find sustainable farming practices for soil and water conservation. In this regard, conditioning the soil with biochar (BC) or attapulgite (ATP) has been proved as a feasible method of improving water conservation and soil hydraulic characteristics. However, the interactive effect of BC and ATP on saline soil is still unclear. The objective of this study was to investigate the effect of BC and/or ATP on water retention, pore size distribution, hydraulic characteristic parameter, and shrinkage strain of saline soil through laboratory trials. For this purpose, BC and/or ATP were added to the loam soil at three levels of 0%, 2%, and 4% by weight, and saturated in the sodium chloride solution with a concentration of 5 g L−1. Results showed that the Van Genuchten model accurately fitted the obtained soil water characteristic curve (R2 > 0.99). BC and/or ATP amendments increased saline soil water retention capacity compared to the unamended soil. Soil water retention capacity increased as the ATP application rate increased. The saturated water content, field water holding capacity, soil microporosity, and soil retention effect of 2%BC combined with 4%ATP were higher than other treatments. BC facilitated the reduction of soil shrinkage, and ATP increased soil shrinkage. Axial shrinkage strain was negatively correlated with the application rate of BC, and positively correlated with ATP. 4%BC combined with 2%ATP had the least shrinkage strain. The present results could serve as a theoretical foundation for soil amendments to improve soil quality.

Credit access and agricultural technology adoption nexus in Ethiopia: A systematic review and meta-analysis

Access to credit is a good way to overcome some of the financial obstacles associated with technology adoption by the farmers. In Ethiopia the potential effect of credit on technology adoption is controversial. To determine the overall direction of effect a meta-analysis was done using a total 42 studies. The random effect model and meta regression analysis were applied to unveil the potential effect of credit access on farmers' technology adoption in Ethiopia. The result showed that in Ethiopia farmers adopted agricultural technologies such as chemical fertilizer, high yielding varieties, livestock technologies, soil and water conservation practices, beehive technologies, poultry technologies and ICT technologies. The random effect model output showed that access to credit increases agricultural technology adoption of farmers by 1.23unit, as compared to farmers who have no access to credit. The result from the meta regression output also depicted that family size; total livestock holding and total income were the main factors that determine heterogeneity in the effect of credit access on farmers' technology adoption among farmers. It was concluded that credit is essential to improve technology adoption; however, most farmers in Ethiopia have collateral problems to have access to credit for the adoption of technologies. It was recommended that a lot of improvement is needed from the government and private financial institutions to widen credit provision for the rural communities without collateral which could boost the financial power of the farmers so as to purchase technologies from the market. • In Ethiopia farmers adopted agricultural technologies such as chemical fertilizer, high yielding varieties, livestock technologies, soil and water conservation practices, beehive technologies, poultry technologies and ICTs technologies. • access to agricultural credit is a good way to overcome some of the financial obstacles associated with technology adoption. • The random effect model output showed that access to credit increases agricultural technology adoption of farmers by 1.23unit, as compared to farmers who have no access to credit. • The result from the Meta analysis depicted that family size; total livestock holding and total income were the main factors that determine credit access effect on the farmers' technology adoption.

Do agricultural extension services promote adoption of soil and water conservation practices? Evidence from Northern Ghana

Agricultural environment in many developing economies has become increasingly unpredictable in recent decades as a result of climate change, increasing the risk of crop failure. Access to meaningful information is required to mitigate the negative effects of the changing environment. This study examined the impact of agricultural extension services on the adoption of soil and water conservation (SWC) practices using data obtained from farming households in Northern Ghana. A multivariate probit model was used to assess the simultaneous or/and substitution adoption of SWC practices, while endogenous switching probit (ESP) was used to estimate the impact of extension services on adoption of SWC practices to account for observed and unobserved heterogeneities. The results showed that most of the SWC practices were adopted jointly, and factors such as non-farm economic activites and farm size influence the adoption of SWC practices. Moreover, farmers who accessed agricultural extension services had a higher probability of adopting most of the SWC practices (crop rotation, contour ploughing and manure application), and those who did not benefit from extension services would have had an equally higher likelihood of adopting the SWC practices had they accessed the services. The findings of the study imply that enhancing agricultural extension services will reduce adoption gaps in SWC practices, and consequently reduce farmers’ exposure to climate-related agricultural production risks. With growing information and communication technologies, pluralistic extension service delivery that mixes governmental and private-sector-led approaches to extension operations to foster demand-driven extension delivery services are highly recommended.

Prioritizing sub-watersheds for soil and water conservation via morphometric analysis and the weighted sum approach: A case study of the Geba river basin in Tigray, Ethiopia

Ranking watersheds according to their susceptibility to soil erosion is crucial in setting priorities for soil and water conservation initiatives. The main intention of this work is to characterize and prioritize 12-sub-watersheds of the Geba River Basin, northern Ethiopia for planned soil and water conservation practices. SRTM-DEM, GIS, and statistical correlation-based weighted sum approach have been utilized for generating morphometric parameters, data processing, and calculating the combined rank of sub-watersheds respectively. Fourteen morphometric parameters that have high nexus with the soil erosion susceptibility were selected and quantified using different standardized mathematical equations. Based on these quantified variables, a compound factor (rank) was calculated for each sub-watershed. Using the combined rank, the sub-watersheds were clustered into five soil erosion susceptibility zones, i.e., very high, high, moderate, low, and very low. Results revealed that sub-watersheds 7, 8, 9, and 12 which collectively cover the majority of the area (36 % of the total area) are possibly fall under the very high soil erosion susceptibility. The high (comprising of sub-watersheds 1, 5, 11), moderate (consisting of sub-watersheds 2, 3), low (consisting of sub-watershed 10), and very low (consisting of sub-watersheds 4, 6) soil erosion susceptibility zones cover 26%, 28%, 4%, and 6% of the total area respectively. The results further reflect that sub-watersheds in the very high soil erosion susceptibility category require immediate action for implementing soil and water conservation measures. This study’s findings could serve as a basis for policymakers and planners in the development of erosion control strategies.

Understanding the impact of sustainable land-scape management practices on farm productivity under intensifying tropical cyclones: Evidence from Southern Malawi

Southern Malawi is continuously affected by tropical cyclone-related floods (TCRFs), which have negative consequences on households' livelihoods, thereby displacing most households to neighbouring communities of Mozambique. The TCRFs have further threatened national, regional, community, and household food security agenda, which is already constrained by poverty, poor agricultural practices, low use of improved varieties, unaffordable inorganic fertilizers, and fragmenting landholding sizes. Accordingly, households have indigenously engineered resilience-based Sustainable Landscape Management (SLM) practices, like intercropping, agroforestry, cover cropping, and soil and water conservation practices, against the adverse effects of TCRFs on-farm productivity. Hence, this study examines the effect of TCRFs and SLM adoption on-farm productivity. While using rigorous endogenous switching regression econometric tools, the study finds TCRFs reducing farm productivity by 27 percent. After SLM adoption, the study observes farm productivity enhancement by 29–126 percent when households adopt at least one SLM practices under varying degrees of TCRFs. Despite the highlighted advantages of SLM adoption, female farmers are less likely to adopt SLM practices because they do not have access to productive resources. Hence, the study proposes the need of gender targeted extension services, accompanied by some seed capital for SLM adoption. Besides, there is need to sensitize farmers on the complementarities between inorganic fertilizer and SLM practices. Lastly, future studies should assess the effect of sustained SLM adoption or dis-adoption and input intensification on farm productivity.

Assessment of Farmers’ Perceptions on Soil Erosion and Soil Conservation Techniques in Zing Local Government Area of Taraba State, Nigeria

In Zing LGA of Taraba State, the study evaluated farmers’ perceptions of soil erosion and their soil conservation practices. To gather information for the study from the farmers and the farmland, field observation, informal interviews, and the use of research instruments including questionnaires and remotely sensed imageries were all used. These data were analyzed in a Windows and GIS context using SPSS 23. The results indicate that 68% of respondents are men, while 32% are women farmers, 71% of whom are married and 50% of them fall within the 41–50 age range. Additionally, 70% of farmers have large families with a size range of 9 to 12 individuals, and 86% of farmers are literate. High incomes are generated by the farmers. According to the study, 89.1% of farmers have farms on steep to mild slopes and do not see soil erosion as a specific issue on their property. However, because they believed that the loss of arable land was the primary consequence of soil erosion, they kept an eye out for physical indicators (such as soil color) on their farms. Geographically, soil erosion is more likely to occur in the eastern to the north-eastern portion of the Zing LGA. Terracing, shaping ridges, along contours, and mulching are soil conservation techniques that have been employed for a long time and are advised to be continue.

Roles of the stolon and erect grass species in surface–subsurface flow generation and red soil loss

Grass planting is an important and typical measure for soil and water conservation, while the roles of stolon and erect grass species in affecting surface–subsurface flow and soil erosion processes are little understood. Experimental plots (2 m × 0.5 m × 0.5 m) using red soil with two rainfall intensities (60 and 120 mm h−1) and grass coverage (30 % and 70 %) were conducted in laboratory rainfall simulation experiments. Two common and endemic stolon (Eremochloa ophiuroides) and erect (Lolium perenne) grass species were selected due to their fast growth, power adaptability, and wide application in reducing runoff and soil loss; and the bare soil plot was set up as the control. The results showed that bare plot had the highest mean surface flow coefficient (73.5 %), and then were L. perenne (57.1 %) and E. ophiuroides (44.9 %). The mean subsurface flow coefficients were found in order of E. ophiuroides (25.7 %), L. perenne (13.0 %) and bare plot (7.2 %). The role of stolon grass rather than erect grass in reducing surface flow but improving subsurface flow led to lower surface flow hydraulic characteristics such as flow velocity, Reynolds number, Darcy–Weisbach coefficient and Manning friction coefficient, and hydrodynamic characteristics like flow shear stress and stream power. Furthermore, the stolon grass generated the lowest soil loss rate (0.8 g m−2 min−1), while the values on erect grass and bare plot were 2.5 and 10.7 g m−2 min−1, respectively. The indicator of eroded sediment median size also proved the higher efficiency of stolon grass in soil loss control, with values of 31.8, 58.6 and 69.6 μm on stolon grass, erect grass and bare plots, respectively. The lower soil loss on stolon grass cover plot was attributed to the lower surface flow and hydraulic–hydrodynamic characteristics. The stolon grass was more sensitive to the coverage and rainfall intensity, which was explained by the higher flow and sediment trapping capability (2.2 ∼ 4.4 times) under lower coverage and rainfall intensity than erect grass, even under high rainfall intensity (1.1 ∼ 3.2 times). The stolon grass played more beneficial roles in soil and water conservation than erect grass, which was closely related to above-ground and under-ground parts of grass. This study can provide a better understanding of the roles of stolon and erect grass species for soil and water conservation and management practices.

Understanding Future Climate in the Upper Awash Basin (UASB) with Selected Climate Model Outputs under CMIP6

Climate change makes the climate system of a given region unpredictable and increases the risk of water-related problems. GCMs (global climate models) help in understanding future climate conditions over a given region. In this study, 12 GCMs from the CMIP6 (coupled model intercomparison project six) were evaluated and ranked based on their abilities to describe the historical observed series. The ensemble mean of bias-adjusted best five models of average annual precipitation showed an increment with an uncertainty range of (2.0–11.9) and change in the mean of 6.4% for SSP2-4.5 and (6.1–16.1) 10.6% for SSP5-8.5 in 2040–2069 relative to the historical period. Similarly, for 2070–2099, increments of (2.2–15.0) 7.9% and (11.8–29.4) 19.7% were predicted for the two scenarios, respectively. The average annual maximum temperature series showed increments of (1.3–2.0) 1.6 °C for SSP2-4.5 and (1.7–2.3) 2.0 °C for SSP5-8.5 in 2040–2069. At the same time, increments of (1.7–2.3) 2.0 °C and (2.8–3.2) 3.0 °C were predicted for 2070–2099. Furthermore, it was predicted that the average annual minimum temperature series will have increments of (1.6–2.3) 2.0 °C and (2.2–2.9) 2.5 °C for 2040–2069 and (2.1–2.7) 2.4 °C and (3.7–4.2) 4.0 °C for 2070–2099 for the two scenarios, respectively. An increase in precipitation with increased land degradation in the sub-basin results in a higher risk of flood events in the future. Improved soil and water conservation practices may minimize the adverse impacts of future climate change on the loss of agricultural productivity.

Spatial Estimation of Soil Loss and Planning of Suitable Soil and Water Conservation Interventions for Environmental Sustainability in Northern Karnataka in India Using Geospatial Techniques

The selected study area lies in Karnataka State of Southern India and is frequently subjected to prolonged dry spells, high soil erosion, declining groundwater levels, and reductions in crop yield. In order to make this region sustainable, estimation of soil loss, selection and prioritization of suitable interventions, and its adoption are very important. In this study, spatial soil loss estimation models were developed sub-district-wise using the Revised universal soil loss equation (RUSLE) and GIS for a period of 70 years (1951 to 2020). The observed soil loss data for the period of 2011 to 2015 were used for validation of the model (R2 = 0.89) and were found satisfactory. The average annual rainfall ranged spatially from 420 to 3700 mm, erosivity (R) ranged from 2606 to >15,000 MJ mm ha−1 h−1 year−1, and average annual soil loss varied from <2.0 to >15.0 t ha−1 y−1 in the northern dry zone of Karnataka. Most of the study area had an average annual rainfall of 550 to 800 mm and the soil loss was <10.0 t ha−1 y−1. A higher erosivity and soil loss occurred in the western part of the selected area where high rainfall is predominant. A considerable variability in rainfall, erosivity, and soil loss was found in high, medium, and low-rainfall regions from 1951 to 2020. The spatial soil loss was estimated catchment-wise and prioritized to determine the vulnerable areas. It was found that 7.69% of the area with soil loss ≥ 15.0 t ha−1 y−1 needs top priority for planning interventions (Priority 1) followed by 10.49% of the area with soil loss ranging from 10.0 to 15.0 t ha−1 y−1 (Priority 2) and 42.7% of the area under 5.0 to 10.0 t ha−1 y−1 (Priority 3), and the remaining area has lower priority. In order to make Northern Karnataka more sustainable, suitable site-specific moisture conservation practices and water-harvesting/groundwater recharge structures were planned using geospatial techniques. Among the selected moisture conservation interventions, conservation furrow and contour cultivation are very suitable for all the nine districts followed by compartmental bunding and semi-circular bunds. Out of the total area, conservation furrow was found suitable for 45.3% of the area, contour cultivation for 24.3% of the area, and compartmental bunding and semi-circular bunds for 16.8 and 16.9% of the areas, respectively. The study indicated that a considerable amount of topsoil is lost as erosion and, hence, planning and adoption of suitable in situ soil and water conservation practices and water-harvesting/groundwater recharge structures are the need of the hour for the sustainable management of this region. The identified locations were validated using visual interpretations, ground truth, and recorded data.

High soil carbon sequestration rates persist several decades in turfgrass systems: A meta-analysis

Managed turfgrass is a common component of urban landscapes that is expanding under current land use trends. Previous studies have reported high rates of soil carbon sequestration in turfgrass, but no systematic review has summarized these rates nor evaluated how they change as turfgrass ages. Here we conducted a meta-analysis of soil carbon sequestration rates from 63 studies globally, comprised mostly of C3 grass species in the U.S., including 24 chronosequence studies that evaluated carbon changes over 75 years or longer. We showed that turfgrass established within the last ten years had a positive mean soil C sequestration rate of 5.3 Mg CO2 ha−1 yr−1 (95% CI = 3.7–6.2), which is higher than rates reported for several soil conservation practices. Areas converted to turfgrass from forests were an exception, sometimes lost soil carbon, and had a cross-study mean sequestration rate that did not differ from 0. In some locations, soil C accumulated linearly with turfgrass age over several decades, but the major trend was for soil C accumulation rates to decline through time, reaching a cross-study mean sequestration rate that was not different from 0 at 50 years. We show that fitting soil C timeseries with a mechanistically derived function rather than purely empirical functions did not alter these conclusions, nor did employing equivalent soil mass versus fixed-depth carbon stock accounting. We conducted a partial greenhouse gas budget that estimated emissions from mowing, N-fertilizer production, and soil N2O emissions. When N fertilizer was applied, average maintenance emissions offset 32% of C sequestration in recently established turfgrass. Potential emission removals by turfgrass can be maximized with reduced-input management. Management decisions that avoid losing accrued soil C—both when turfgrass is first established and when it is eventually replaced with other land-uses—will also help maximize turfgrass C sequestration potential.

Evaluation of reservoir sedimentation using bathymetry survey: a case study on Adebra night storage reservoir, Ethiopia

Reservoir sedimentation is a serious challenge that reduces reservoir life. Because it decreases the initial capacity of the reservoir and has an impact on drinking water supply, irrigation, and hydropower activities. Inadequate land activities and poor management techniques cause soil erosion and reduce reservoir storage capacity. As a result, accurate sediment estimation was assist in the adoption of sustainable land-use activities and best management practices that lead to effective reservoir operations. The main objective of this study was to evaluate the rate of sedimentation and remaining capacity of Adebra night storage reservoir (NSR) using a bathymetric survey and Arc-GIS 10.8. A comparison of original and current reservoir capacity was used to evaluate the quantity of sediment deposition in the reservoir. The latter was developed using Arc-GIS 10.8 and a bathymetry survey that was used to develop the TIN surface and evaluate reservoir volume. The Adebra NSR reservoir capacity was decreased by the accumulation of sedimentation from 36,902 m3 in 2012 to 27,722 m3 in 2020. The results of this study showed that the Adebra night storage reservoir had lost on average 24.8% of its capacity due to sedimentation, during 8 years of operation. The average deposition rate of sedimentation in Adebra NSR was estimated to be 1147.5 m3/year, with a loss rate of 3.1% per year. The value of sedimentation rates found in live storage of the reservoir area was 1147.5 m3/year. At the current time, the expected life of the night storage reservoir was reduced due to a lack of proper soil conservation practices in the reservoir catchment areas. In general, the study finding showed that the capacity of NSR was reduced by the accumulation of sedimentation year to year throughout the design period. Therefore, to improve the capacity of NSR should be planning and implementing different techniques of sediment control and removal, depending on the estimation of sediment production from watersheds of inlets and outlets of reservoirs.

Soil erosion risk under climate change scenarios: A case study in rural area with varying land uses

Soil erosion is one of the major issues in the tropics. The erosion is highly affected by the changes in climate and land cover. Future changes in tropical climate, particularly precipitation are expected to influence the potential risks of soil erosion. In the face of rapid changes in rural land cover for agricultural purposes, the combined forcings of land cover and climate changes have been to be a major threat to the soil conservation due to soil erosion. In this study, climate change scenarios at the northern part of Borneo were developed based on the RCP 4.5 and RCP 8.5 climate scenarios using Weather Research Forecast Model (WRF). The future climate projection scenarios of the total precipitation were used to simulate the potential erosion risks in varying land covers in a rural area of Sabah, Malaysia. The RUSLE model was used for soil erosion modelling, which was integrated with IDRISI Selva that allow the analysis and assessment of erosion risk. The variability of future total precipitations in the area of varying land cover types have resulted in varying degree of potential soil erosion risk The average soil loss at the studied area has increased by 262 t/ha/yr with 35.94 % increment in annual precipitation under RCP 8.5 emission scenario. However, under RCP 4.5, 26.65 % decrement in precipitation has reduced the soil loss by 315.1 t/ha/yr. In this rural area, exceptionally high soil erosion was found at steep slopes and thin vegetation covers. Therefore, an appropriate land use planning, soil conservation practices, and strategic adaptation options plan should be created and developed to ensure the sustainability of the soil conservation and enhance rural agricultural productivity.

Review on the Effects of Land Use on Soil Physical and Chemical Properties in Ethiopia

Land use is one of the main chauffeurs of many processes of environmental change, as it influences basic resources within the landscape, including the soil resources. Changes in land practice and soil management practice can have a marked effect on soil physical and chemical properties. Depend on the land use soil chemical and physical properties has different effects either positive and negative effects. The purpose of this review paper is to review the effects of land use on the soil physical and chemical properties in Ethiopia. Conversion of land use types from one to another has adverse effects on soil properties, especially overgrazing and cultivation of deforested land. Therefore, the proper soil and water conservation practice are important in the different area to enhance soil fertility and crop productivity. The results of different studies indicate that soil on bulk density (BD), particle density (PD) and total porosity (TP) of the cultivated land is highest than that of forest land. But the grassland had lower bulk density than the cultivated land which could be due to restricted grazing at the grassland to harvest fodder and free grazing on crop lands after harvest and continuous ploughing at the same depth of cultivated lands. Different finding suggested that the highest soil pH values of 5.61 and 5.52 in surface soil were found under the grassland; whereas, the lowest pH and also the organic matter of cultivated soil is low from that of forest land and grass land.From the results of the review it was possible to conclude that conversion of forest lands to cultivated and grasslands had detrimental effects on the soil physio-chemical properties under subsistence farming systems of the different area. It is, therefore, recommended that appropriate and integrated land management options for different land use systems are required to sustain agricultural productivity while protecting the environment. Generally, Land use has great effects on soil physical and chemical properties by different it may affect positively or negatively. Keywords: Land use type, soil physical and chemical properties DOI: 10.7176/JRDM/89-02 Publication date: November 30 th 2022

Farm Households Choices of Adaptation Strategies to Climate Variability Challenges in Benishangul Gumuz Regional State, Western Ethiopia

Climate variability and change are a serious threat to the livelihoods of rural communities because they are very sensitive to such changes. This study assesses the major adaptation strategies pursued by farm households to climate variability and change impact in Benishangul Gumuz regional state, western Ethiopia which is harshly affected by climate change stresses. The data were collected from a randomly selected 385 sample households through interview using field-based questionnaires and focus group discussions and analyzed using descriptive statistics. The results pointed out that the likelihood of households to adopt crop diversity, soil and water conservation practice, small scale irrigation, crop rotation, adjusting planting date and improved crop varieties were 54.2%, 49.8%, 47.3%, 45.3%, 44.4% and 43.5% respectively. Moreover, the results indicated that the joint likelihood of using all adaptation strategies was only 1.64% and the joint likelihood of failure to adopt all of the adaptation strategies was 2.92%. Therefore, future policy should focus on towards supporting improved extension service, offer climate related training and information especially to adaptation technologies to increase the farm households experience in adopting different strategies to the negative effects of climate variability which is a global problem of this century.

Erosion susceptibility mapping in the Central-Eastern Region of São Paulo in the last few decades.

Soil degradation has become a critical global environmental challenge as a result of rapid population growth, intensified erosion, and increased global warming. Depletion of nutrients, decreased infiltration, availability of water in the subsoil, silting, and eutrophication of surface water resources are directly associated with soil degradation. Water erosion is one of the primary causes of erosion. The principal objective of this study was to understand how climate change and land use have affected susceptibility to erosion in the central-eastern region of the state of São Paulo, Brazil, over the past few decades. Using the technique of multicriteria decision analysis and comparison of thematic layers in pairs, different factors that contribute to soil erosion were integrated in a GIS environment to map erosion hotspots. The results indicated increasing very high, high, and medium erosion susceptibility class percentage. Slope and soil types were the most sensitive factors; however, changes in land use, in particular, increased land cultivation and expanded areas highly susceptible to erosion in late 2019. The results of this study will assist in implementing soil conservation practices in such areas, reducing soil degradation, and increasing productivity.

Water Use Efficiency of Maize (Zea mays L.) Crop under Selected Soil and Water Conservation Practices along the Slope Gradient in Ruzizi Watershed, Eastern D.R. Congo

Maize (Zea mays L.) productivity is constrained by water shortages in the predominantly rainfed agriculture of the tropical semi-arid Ruzizi Plain, in the eastern Democratic Republic of Congo (DRC). The region is characterized by a high seasonal and inter-annual rainfall variability and a frequent occurrence of consecutive dry days within growing seasons. Consequently, planning water utilization in rainfed agriculture has become complex, as appropriate soil water conservation (SWC) practices are lacking among most smallholder farmers. Identifying practices that increase water use efficiency (WUE) along the slope gradient is crucial for supporting maize production in the region. In this study, we assessed, for three growing seasons, the effectiveness of two SWC practices (tied ridges and Zai pits) in improving the WUE of two maize varieties along three slope gradients (0–2, 2–8, and 8–15%) in the tropical semi-arid Ruzizi Plain. In this area, rainfall amounts (142–289 mm) were consistently below the evapotranspiration demands (356–533 mm) across the three growing seasons. Tied ridges recorded the highest grain yield (2.16 t ha−1) and WUE (15.23 kg mm−1), especially at low slopes, when compared to Zai pits and conventional tillage. For all SWC practices, WUE decreased with the slope gradient (p < 0.01). Furthermore, a decrease in stored soil water (SWS) at silking and maturity stages (milk, dough, and dent stages) negatively affected the WUE. The variety had no significant effect on grain yield and WUE. Root biomass (RBM), shoot biomass (SBM), and leaf area index (LAI) at the flowering stage were the most associated with the WUE (R2 = 58.5%). In conclusion, tied ridges showed potential for improving maize WUE and yield in the water-deficient conditions that characterize the Ruzizi Plain, and could be promoted to improve the maize productivity among smallholder farmers.

Climate change adaptation options to inform planning of agriculture and food systems in The Gambia: A systematic approach for stocktaking

Identifying and assessing adaptation options are key pre-requisite steps to adaptation prioritization and effective adaptation planning. In this paper, we presented a systematic approach for adaptation stocktaking, combining a systematic mapping and an outcome-oriented and evidence-based assessment, illustrated using the case of The Gambia. This study systematically mapped 24 adaptation options that can potentially inform adaptation planning in The Gambia agriculture and food systems and assessed how the identified options contribute to the pillars of Climate-Smart Agriculture. Because of the paucity of evidence sources from The Gambia, we collated evidence from both The Gambia and the West Africa region. We found that many of the documented options, such as climate-resilient crop varieties, crop diversification, climate information use, and weather indexed-based insurance have the potential to increase agricultural productivity and income while building resilience to climate change. While several options, such as soil and water conservation practices can positively contribute to climate change mitigation, others such as manure and inorganic fertilizers can have no or negative impacts on mitigation. Agroforestry practices and System of Rice Intensification have the potential to make a triple impact. The paucity of evidence from The Gambia and the highly contextual and differential impacts of the identified adaptation options underscore the importance of careful consideration of barriers and enablers when developing and deploying policy and interventions to sustainably increase productivity and income while building resilience to climate risks and reducing GHGs emissions. Stakeholder engagement and participatory research action are crucial in selecting and testing the priority adaptation options which can maximize their potentials in specific agricultural and food system contexts, such as in The Gambia. Because of the heterogeneity in household vulnerability and socioecological circumstances, targeting options to the right contexts will also be crucial to avoid maladaptation. We highlighted key knowledge gaps in the understanding of the effectiveness and feasibility of the identified adaptation options in The Gambia. Beyond The Gambia, the approach can also be useful for and replicated in other least developed countries in the West African region, that are currently developing their National Adaptation Plan.

Smallholder farmers' perception of climate change and choice of adaptation strategies in East Hararghe Zone, Eastern Ethiopia

PurposeChange of climate is attributed to human activity that alters the composition of the global atmosphere observed over comparable periods. The purpose of this paper is to explore smallholder farmers' perceptions of climate change and compare it with meteorological data, as well as to identify perceived adaptation barriers and examine the factors that influence the choice of adaptation options in eastern Ethiopia.Design/methodology/approachIn total, 384 sample households were chosen from four districts of the zone. A cross-sectional survey was used to conduct the study. Primary data was acquired through key informant interviews, focus group discussions and semistructured interviews, whereas meteorological data was collected from the National Meteorological Service Agency of Ethiopia. A Mann–Kendall statistical test was used to analyze temperature and rainfall trends over 33 years. A multivariate probit (MVP) model was used to identify the determinants of farmers' choice of climate change adaptation strategies.FindingsThe result indicated that temperature was significantly increased, whereas rainfall was significantly reduced over the time span of 33 years. This change in climate over time was consistently perceived by farmers. Smallholder farmers use improved varieties of crops, crop diversification, adjusting planting dates, soil and water conservation practices, reducing livestock holdings, planting trees and small-scale irrigation adaptation strategies. Moreover, this study indicated that sex of the household head, landholding size, livestock ownership, access to extension, access to credit, social capital, market distance, access to climate change-related training, nonfarm income, agroecological setting and poverty status of the households significantly influence farmers’ choice of adaptation strategies.Research limitations/implicationsFurther research is required to evaluate the economic impact of each adaptation options on the livelihood of smallholder farmers.Practical implicationsInstitutional variables significantly influenced how farmers adapted to climate change, and all of these issues might potentially be addressed by improving institutional service delivery. To improve farm-level adaptation, local authorities are recommended to investigate the institutional service provision system while also taking demographic and agroecological factors in to account.Originality/valueThis study compared farmers' perceptions with temperature and rainfall trend analysis, which has been rarely addressed by other studies. This study adopts an MVP model and indicated the adaptation strategies that complement/substitute strategies each other. Furthermore, this study discovered that the choice of adaptation options differed between poor and nonpoor households, which has been overlooked in previous climate change adaptation research.

Anthropogogical Model of Agricultural Extension: sensitivity of the social return on investment

Introduction / objective: the scarcity of resources for social investments requires strategies that increase the availability of information for decision-making. The Social Return on Investment (SROI) is a tool used for impact measurement and makes it possible to economically assess the effects of an intervention and identify the amount of change generated by each monetary unit invested. This index admits sensitivity analysis to recognize the aspects with the greatest influence on the impact of a project, so the objective of this work was to study the sensitivity of the SROI in the cocoa Territorial Laboratories of the University of Antioquia. Methodology: Through graphs, each of the changes was related to the SROI, identifying the highest levels of sensitivity in those whose values were located in quadrants 1 and 3 and whose trend line had an ascending performance. Results: The most sensitive variables were: the projection of income for 20 years, the increase in cocoa production, production above the break-even point, the satisfaction of basic and social needs, informal agreements for the succession of the production system, the initiation of soil conservation practices, the definition of activities to achieve the dream farm, and the implementation of the anthropogogical model of agricultural extension. Conclusions: Interrelationships were found between most of these variables and it was concluded that integral initiatives are the key to achieve greater social changes.

Does the Availability of Specific Agri-Equipment Influence Cropping System Design? A Case Study of Pulses

Cropping system design is being transformed through the twofold evolution of agricultural practices for an agroecological transition, and of equipment diversification for agrotechnical needs. Among the most well-known drivers there are genetic selection, crop diversification, protein and energy autonomy. Protein and energy autonomy but also crop diversification could be achieved by reintroducing pulses into farming systems. The availability of specific equipment might be the simplest prerequisite for developing agroecological farming practices while supporting these goals. However, the links between pulses and agri-equipment are not clarified in the literature. The aim of this study is to understand recent historical and current links between pulses and equipment and to gain insight into the suitability or even to find shortcomings concerning pulses and available agri-equipment. To this end, 21 key informants were identified in the agronomical, sociotechnical, economic, and political sectors in France. We asked them four questions: (i) Can you describe your professional functions? (ii) Do you think that equipment is related to the design of the culture system? (iii) Do you think that pulses require specific equipment? (iv) How do you define agroecology? Respondents’ profiles are equally distributed into profiles directly related to the farmer and profiles not directly related to farmers. All 21 respondents answered questions (ii) and (iv). Only 14 respondents answered question (iii), and most of them are directly related to the farmer. We note that pulses do not require specific agri-equipment in a conventional system. The need for agri-equipment is found in the soil conservation approach where pulses are combined with other crops. Soil conservation approaches appear to achieve agroecological goals through the reintroduction of legumes and the decarbonization of energy associated with reduced mechanical costs and CO2 emissions. This article presents expert opinions on the impact of equipment in the adaptation of agroecological practices as well as insights into the existing blockages of equipment in relation to soil conservation practices.