Alternative Land Management Research Articles

Host tree-based scenario modelling for predicting a key edible insect, mopane worm Gonimbrasia belina (Westwood, 1894) distribution in Southern Africa

Abstract Gonimbrasia belina, known as the mopane worm, is a large edible caterpillar in tropical and subtropical regions. However, little is known about the bioecology of this species as influenced by its host trees. This study evaluated the importance of different potential host trees in understanding mopane worms’ behaviour and spatial distribution. To assess their relative importance, the study compared models incorporating various mopane worm host trees and predictor variables. Using the species distribution modelling (SDM) package in R, an ensemble of random forest (RF), support vector machine (SVM), and boosted regression tree (BRT) algorithms were used to assess the spatial extent of mopane worm distribution in Southern Africa. Four host tree-based scenarios were developed to assess their contribution to the relative distribution of the mopane worm i.e. (1) by excluding all the potential host trees as explanatory variables and considering only the environmental variables, (2) focusing on the primary host tree, Colophospermum mopane as an explanatory variable together with the other environmental variables, (3) incorporating all the host trees, including C. mopane and (4) examining all other host trees excluding C. mopane. Results demonstrated that incorporating all host trees enhanced the models’ predictive abilities (mean AUC = 0.87) underscoring the significant impact of the alternative host trees on the mopane worm distribution patterns beyond just the C. mopane. This study highlights the significance of host trees in predicting the behaviour and distribution of mopane worm populations, providing valuable insights and decision-making for mopane worm use as an alternative protein source, conservation efforts, and land management practices.

State of Knowledge on UK Agricultural Peatlands for Food Production and the Net Zero Transition

Agricultural peatlands are the most productive soils in the UK for the cultivation of many food crops. Historical drainage of peat for agriculture (i.e., cropland and managed grassland), without consideration of other associated environmental and climatic impacts, has resulted in a significant emission of greenhouse gases (GHGs). There is a need to reduce GHG emissions without compromising the rural economy and jeopardizing food security in the UK to a greater extent than is currently being experienced. In March 2023, in a bid to identify alternative land management systems for agricultural peatlands to support the UK’s commitment to achieving net zero GHG emissions by 2050, a group of forty investigators met at a workshop convened by the AgriFood4NetZero Network+. The workshop reviewed the state of knowledge surrounding the Fens of Eastern England and their importance for food provision, the economy, cultural identity, and climate change mitigation. A broad consensus emerged for research into how GHG emissions from agricultural peatlands could be reduced, whether alternative farming methods, such as seasonal farming or paludiculture, would offer a solution, and how a localized approach for the Fens could be defined. The development of a holistic, inclusive, and plausible land use scenario that considers all aspects of ecosystem services provided by the Fens is urgently needed.

Designing Iowa Agricultural Landscapes to Improve Environmental Co-Benefits of Bioenergy Production

Cellulosic bioenergy feedstocks are needed to improve carbon (C) management while provisioning biomass for bioproducts and biofuel. The transition to increased cellulosic biomass production can be guided by land management plans designed to improve economic, environmental, and ecological performance. We constructed a sustainability model to compare landscape designs for biofuel production from corn (Zea mays L.) stover and switchgrass (Panicum virgatum L.) in central Iowa, USA. We used the model to compare environmental and socioeconomic outcomes associated with four landscape management strategies, with and without cellulosic biomass markets. We evaluated (1) a fuelshed area containing over 1.2 million ha (3 million acres) of corn and soybean (Glycine max (L.) Merr.) within 80 km (50 miles) of a commercial-scale cellulosic biorefinery in Nevada, Iowa, and (2) the South Fork watershed containing over 72,000 ha (178,000 acres) of these row crops within eight north central Iowa HUC-12 (hydrologic unit code) watersheds. At both landscape scales, we found that it is possible to achieve multiple environmental and socioeconomic benefits concomitantly with cellulosic biomass production by strategically collecting corn stover and converting the 10% of the lowest-profitability row crop land to perennial switchgrass. Potential benefits from landscape design include increased biodiversity, soil and water quality improvements, increased soil carbon sequestration for climate change mitigation, and reduced fertilizer use and cost. Our model results showed that increasing benefits can accrue when complementary conservation practices (e.g., reduced tillage, use of a rye cover crop) are combined and integrated throughout a fuelshed or watershed area. We conclude that ecologically based landscape designs offer valuable insights about costs and benefits of land management alternatives, with relevance for achieving stakeholder goals.

An Approach for Managing Landscapes for a Variety of Ecosystem Services in Prespa Lakes Watershed

The main goal of this research was to evaluate how well existing and emerging land management practices may be used to manage landscapes for various ecosystem services. By employing a mixed methods approach and conducting a case study in the Prespa Lakes watershed in southeast Europe, this goal was achieved. The necessary information was initially gathered using a semi-stratified survey. Following that, the primary ecosystem services and land management practices present in Prespa Lakes watershed were determined via a workshop and a Delphi survey. The identified ecosystem services were ranked using the multi-criteria analytical hierarchy process method. The most important ecosystem service topics included tourism and recreation, maintenance of healthy water bodies, wildlife habitats, healthy food production, natural and heritage values, and biodiversity. Finally, a set of primary priority land management practices for meeting production and ecosystem service goals in the current conditions of the Prespa Lakes watershed was produced utilizing a ranking framework. The very high priority land management practices include livestock breeding to meet both production and conservation objectives, organic farming, diversified crop rotation, crop and tree diversity, restored wetlands, and planning at landscape level. This study provides an important tool for assessing changes in ecosystem service provision under alternative land management practices.

Agroecological and agroforestry strategies to improve organic hibiscus productivity in an Indigenous non-governmental organization from Mexico

Abstract La Montaña region, in southern Mexico, is characterized as a highly human-modified landscape with a rough topography, extreme poverty and structural violence. In this region, Xuajin Me'Phaa, an Indigenous non-governmental organization conformed by ca. 300 peasants, implements productive restoration projects and trades organic hibiscus (Hibiscus sabdariffa L.) as its main monetary income. Nonetheless currently, organic hibiscus yield is low compared to the potential yields in the region. Thus, it is necessary to explore alternative sustainable land management systems which enable farmers to increase hibiscus crop productivity, while halting land degradation. This study assessed the impact of six different agroecological fertilization protocols (AFPs) on hibiscus productivity planted in an alley cropping system with Calliandra houstoniana trees. The AFPs were based on the combination of three local plant amendments: C. houstoniana mulch, Mucuna pruiriens var. utilis green manure and hibiscus stover, and a commercial bio-fertilizer (Azospirillum + Rhizophagus). Simultaneously, the performance of C. houstoniana trees was assessed. The AFPs were applied in the alley cropping system and evaluated from 2016 to 2018. After 3 years, in the AFPs which included C. houstoniana mulch, hibiscus yielded significantly more (419 ± 27 kg dry calyxes ha−1 in average) than AFPs which did not include this species (264 ± 15 kg ha−1). The 18-month-old C. houstoniana trees yielded 0.6 t ha−1 of dry biomass and 1.12 t ha−1 of wooden stakes, a relatively low production. In conclusion, our results show that alley cropping with a denser arrangement of C. houstoniana trees in combination with mulching of this tree species, and use of mucuna green manure represent a promising agroforestry system for organic hibiscus production.

Ecological and economic implications of alternative metrics in biodiversity offset markets.

Policy tools are needed that allow reconciliation of human development pressures with conservation priorities. Biodiversity offsetting can be used to compensate for ecological losses caused by development activities. Landowners can choose to undertake conservation actions, including habitat restoration, to generate biodiversity offsets. Consideration of the incentives facing landowners as potential biodiversity offset providers and developers as potential buyers of credits is critical when considering the ecological and economic landscape-scale outcomes of alternative offset metrics. There is an expectation that landowners will always seek to conserve the least profitable land parcels, and, in turn, this determines the spatial location of biodiversity offset credits. We developed an ecological-economic model to compare the ecological and economic outcomes of offsetting for a habitat-based metric and a species-based metric. We were interested in whether these metrics would adequately capture the indirect benefits of offsetting on species not considered under a no-net-loss policy. We simulated a biodiversity offset market for a case study landscape, linking species distribution modeling and an economic model of landowner choice based on economic returns of the alternative land management options (restore, develop, or maintain existing land use). Neither the habitat nor species metric adequately captured the indirect benefits of offsetting on related habitats or species. The underlying species distributions, layered with the agricultural and development rental values of parcels, resulted in very different landscape outcomes depending on the metric chosen. If policy makers are aiming for the metric to act as an indicator to mitigate impacts on a range of closely related habitats and species, then a simple no-net-loss target is not adequate. Furthermore, to achieve the most ecologically beneficial design of offsets policy, an understanding of the economic decision-making processes of the landowners is needed.

Effects of Different Cropping and Land Management Practices on the Quality of Irrigated Soils of the Upper Awash Basin, Central Rift Valley of Ethiopia

Abstract Irrigation is one way of utilizing the land resources to enhance agricultural production. Irrigation crop production is crucial in the present study area due to its arid and semi-arid climatic characteristics. However, little is known about the influence of different cropping and land management practices on soil quality (SQ). This study aimed to determine the effects of different cropping systems and land management practices on variability of SQ indicators in the Central Rift Valley of Ethiopia (CRVE). To this end, 45 disturbed surface (0‒20 cm) and 24 undisturbed (upper 7 cm) soil samples were collected from four adjacent farms: large-scale perennial farms (LSPF), large-scale annual farms (LSAF), smallholder subsistence annual farms (SHAF), and non-cultivated lands (NCL). Soil analyses were made for selected SQ indicators – particle size analysis, bulk density, soil water content, organic matter, pH, total nitrogen, available potassium and phosphorus, exchangeable bases, and cation exchange capacity. One-way analysis of variance (ANOVA) and Pearson correlation coefficient (r) were computed. Key informants’ interview was conducted to substantiate the data obtained from soil laboratory analyses. As the results confirmed, different cropping and land management practices had significant effects on some SQ indicators. Soil organic matter, total nitrogen, available P, and available K declined significantly (P < 0.05) in the soils of LSAF and SHAF. This is attributed to land management-induced problems such as frequent tillage practice of mono-cropping, high level of mechanization, removal of crop residues/above-ground biomass in LSAF, and use of low external inputs and overcultivation without appropriate land management practices in SHAF. However, LSPF practice resulted in the improvement of key SQ indicators, next to NCL. Therefore, LSPF can be an alternative cropping and land management practice to achieve sustainable agricultural production and land management in semi-arid irrigated lands of CRVE and in places with similar environments.

Using wildfire as a management strategy to restore resiliency to ponderosa pine forests in the southwestern United States

AbstractThe long‐term outcome from accelerated forest restoration using resource objective wildfire in combination with fuel management on fire‐excluded landscapes is not well studied. We used simulation modeling to examine long‐term trade‐offs and synergies of alternative land management strategies by combining two wildfire management alternatives with three levels of contemporary forest restoration treatments on a 778,000‐ha landscape over 56 years. We found that managing wildfires for resource objectives diminished the likelihood of irregular fire events over time by making wildfire activity more predictable. Overall, adding resource objective wildfire reduced the proportion of high‐severity fire in relation to total area burned, but increased total area burned and the area of high‐severity fire. We also found resource objective wildfire changed the distribution of high‐severity burn patches by increasing their total number and range, their likelihood of containing disjunct core areas, and their edge complexity. The results suggested that alongside the current pace of active forest management, expanding the fire footprint to achieve low‐cost restoration carries the potential for increased high‐severity fire and associated impacts to ecological values including old forest structure and wildlife habitat. Concurrently, adding resource objective wildfire expanded the footprint of conventional restoration treatments by fivefold, and restoration objectives were achieved in 25 years when managing resource objective wildfires alongside restoration treatments five times the current pace. This study demonstrates the first fire suppression model to replicate local decision making by fire managers during simulated fire events to manage risk by considering both fire proximity to values at risk, and daily weather conditions. The study paves the way for further investigations of the synergies between wildfires and conventional forest restoration to improve resiliency in fire‐excluded pine forests.

Climate regulation ecosystem services and biodiversity conservation are enhanced differently by climate- and fire-smart landscape management

Abstract The implementation of climate-smart policies to enhance carbon sequestration and reduce emissions is being encouraged worldwide to fight climate change. Afforestation practices and rewilding initiatives are climate-smart examples suggested to tackle these issues. In contrast, fire-smart approaches, by stimulating traditional farmland activities or agroforestry practices, could also assist climate regulation while protecting biodiversity. However, there is scarce information concerning the potential impacts of these alternative land management strategies on climate regulation ecosystem services and biodiversity conservation. As such, this work simulates future effects of different land management strategies in the Transboundary Biosphere Reserve of Meseta Ibérica (Portugal-Spain). Climate-smart (‘Afforestation’, ‘Rewilding’) and fire-smart (‘Farmland recovery’, ‘Agroforestry recovery’) scenarios were modelled over a period of 60 years (1990–2050), and their impacts on climate regulation services were evaluated. Species distribution models for 207 vertebrates were built and future gains/losses in climate-habitat suitability were quantified. Results suggest climate-smart policies as the best for climate regulation (0.98 Mg C ha−1 yr−1 of mean carbon sequestration increase and 6801.5 M€ of avoided economic losses in 2020–2050 under Afforestation scenarios), while providing the largest habitat gains for threatened species (around 50% for endangered and critically endangered species under Rewilding scenarios). Fire-smart scenarios also benefit carbon regulation services (0.82 Mg C ha−1 yr−1 of mean carbon sequestration increase and 3476.3 M€ of avoided economic losses in 2020–2050 under Agroforestry scenarios), benefiting the majority of open-habitat species. This study highlights the main challenges concerning management policies in European rural mountains, while informing decision-makers regarding landscape planning under global change.

A decision-making framework for evaluating environmental tradeoffs in enhancing ecosystem services across complex agricultural landscapes

Decision-making processes to ensure sustainability of complex agro-ecosystems must simultaneously accommodate production goals, environmental soundness, and social relevancy. This means that besides environmental indicators and human activities, stakeholders' perceptions need to be considered in the decision-making process to enable the adoption of mitigation practices. Thus, the decision-making process equates to a multi-criteria and multi-objective problem, requiring additional tools and methods to analyze the possible tradeoffs among decision alternatives based on social acceptability. This study was aimed at establishing a decision support system that integrates hydro-ecologic models and socio-cultural perspectives to identify and assess feasible land management alternatives that can enhance the Kaskaskia River Watershed (KRW) ecosystem services in Illinois (USA). The Soil and Water Assessment Tool (SWAT) was used to simulate the spatio-temporal response of nine environmental predictors to four major management alternatives (crop rotation, cover cropping, reduced tillage, modified fertilizer application) based on stakeholder acceptability and environmental soundness, under 32 distinct climate projections. The stochastic multicriteria acceptability analysis (SMAA) was then applied to classify the management alternatives from the least to the most efficient based on three preference schemes: no preference, expert stakeholders’ preference, and non-expert stakeholders’ preference. Results showed that preference information on watershed ecosystem services is crucial to guide the decision-making process when a broad spectrum of criteria is considered to assess the management alternatives' systemic response. The disparity between expert and non-expert stakeholders' preferences showed different rankings of alternatives across several subcatchments, where the two-year corn one-year soybean rotation scheme was expected to offer the best management alternative to ensure a sustainable agro-production system in the highly cultivated subcatchments of the KRW. In contrast, non-conventional tillage practices were expected to contravene agricultural production, and therefore should be discarded unless combined with complementary measures. This study will enable stakeholders to identify the most suitable management practices to adapt to natural and anthropogenic changes and encourage engagement between government institutions and local communities (multi-stakeholder consensus) to provide a better platform for decision-making.

Reduced runoff and sediment loss under alternative land capability-based land use and management options in a sub-humid watershed of Ethiopia

Study regionLaguna watershed of the Upper Blue Nile basin, which is representative of drought-prone tropical sub-humid watersheds of Ethiopia. The river of the watershed drains into Lake Tana, one of the largest lakes in Ethiopia. Study focusThis study evaluated the impacts of five alternative land capability-based land use and management options in reducing runoff and sediment loss by integrating observed plot- and watershed-scale data with the Soil and Water Assessment Tool. New hydrological insightsWe modified flow- and sediment-sensitive model parameters based on six best-performing plot-scale land management practices to simulate the runoff and sediment loss of the watershed under five alternative options. The results revealed that alternative land use options could reduce runoff and sediment loss by about 21–30% (from 740 to 517 mm) and 32–83% (from 101 to 18 t/ha), respectively, compared to the baseline data. The simulations of best alternative land management options also decreased runoff by 10–41% and sediment loss by 40–89%. Runoff and sediment loss reductions were estimated to be as high as 72% (from 740 to 210 mm) and 95% (from 101 to 5 t/ha), respectively, when land use and land management options are combined. These results indicate that implementing suitable land use and management practices has the potential to rehabilitate degraded watersheds in the sub-humid Ethiopian highlands and similar environments elsewhere.

A framework for integrating the terrestrial carbon stock of estates in institutional carbon management plans

AbstractMany institutions have substantial landholdings, but few consider soil carbon preservation and augmentation in their carbon management plans. A methodical framework was developed to analyse terrestrial carbon stocks (soil and tree biomass) for credible carbon offsetting strategies in institutional land. This approach was demonstrated at two farms (805 hectares) managed by Newcastle University. Soil carbon for three depths (0–30 cm, 30–60 cm and 60–90 cm) and above‐ground tree biomass were quantified. These data provided a terrestrial carbon baseline to evaluate future land management options and effects. Historical land‐use records enabled the following comparisons: (1) agricultural land vs. woodland; (2) arable land vs. permanent grassland; (3) organic vs. conventional farming; (4) coniferous vs. broadleaved woodland; and (5) recent vs. long‐established woodland. Carbon storage (kg/m2) varied with land usage and woodland type and age, but only agricultural land vs. woodland, and for agriculture, arable land vs. permanent grassland, significantly affected the 0–90 cm soil carbon. At the university‐managed farms, current terrestrial carbon stocks were 103,620 tonnes in total (98,050 tonnes from the 0–90 cm soil and 5,569 tonnes from tree biomass). These terrestrial carbon stocks were equivalent to sixteen years of the current carbon emissions of Newcastle University (6,406 tonnes CO2 equivalents‐C per year). Using strategies for alternative land management, Newcastle University could over 40 years offset up to 3,221 tonnes of carbon per year, or 50% of its carbon emissions at the current rate. The methodological framework developed in this study will enable institutions having large landholdings to rationally consider their estates in future soil carbon management schemes.

Applying interval PCA and clustering to quantile estimates: empirical distributions of fertilizer cost estimates for yearly crops in European Countries

The decision to adopt one or another of the sustainable land management alternatives should not be based solely on their respective benefits in terms of climate change mitigation but also based on the performances of the productive systems used by farm holdings, assessing their environmental impacts through the cost of fertilizer resources used. This communication uses the symbolic clustering tools in order to analyze the conditional quantile estimates of the fertilizer costs of yearly crop productions in agriculture, as a replacement proxy for internal soil erosion costs. After recalling the conceptual framework of the estimation of agricultural production costs, we present the empirical data model, the quantile regression approach and the interval principal component analysis clustering tools used to obtain typologies of European countries on the basis of the conditional quantile distributions of fertilizer cost empirical estimates. The comparative analysis of econometric results for yearly crops between European countries illustrates the relevance of the typologies obtained for international comparisons to assess land management alternatives based on their impact on agricultural carbon sequestration in soils.

An optimal modeling approach for reducing carbon footprint in agricultural water-energy-food nexus system

Modern agriculture calls for efficient and environmental-friendly agricultural water and land management practice. Agricultural water and land utilization mode has a great impact on the amount of carbon emissions, and thus the aim of this work is to propose an optimal modeling approach for generating efficient agricultural water and land management alternatives and reducing carbon emission in agricultural water-energy-food nexus system. This study presents a novel approach consisting of carbon footprint lifecycle assessment method and bi-level multi-objective stochastic programming model. The proposed approach has contributions in following aspects: (1) the environmental impact of different resource allocation strategies can be measured in optimization (2) the spatial variability of spatial data (e.g., ET0 and precipitation); can be fully reflected via remote sensing information; (3) tradeoffs among two decision-making levels and their conflicting objectives under randomness of surface water availability can be addressed. The proposed approach was applied to the middle reaches of the Heihe River basin, northwest China. After solving the proposed model, the optimal water and land use alternatives under different hydrological years can be generated. Decision makers can plan agricultural production strategy according to optimization schemes, and reduce carbon emission through increasing vegetable cultivation and surface water utilization. Furthermore, the performance comparison of different models indicated that fierce conflicts exist between income fairness and economic benefits. The comprehensive evaluation value of bi-level multi-objective stochastic programming model is 0.7036, which is highest among single- and multi-objective models, showing that such model has obvious advantage in dealing with multiple decision-making levels and conflicting objectives. This approach can help decision makers of similar regions manage the agricultural production system in a more efficient and environment-friendly way.

Assessing the impacts of agricultural conservation practices on freshwater biodiversity under changing climate

Freshwater systems are some of the most threatened ecosystems in the world. Factors contributing to their degradation can be associated with the expansion and intensification of agriculture in the 20th century, which has led to habitat degradation and water pollution. To mitigate the impacts of agricultural activities and improve stream ecosystem quality, government-funded conservation programs have promoted the implementation of best management practices (BMPs) during the last three to four decades. However, these conservation programs have been implemented within agricultural landscapes without evaluating exhaustively their potential side effects on freshwater species at the watershed scale. This study aimed to assess the changes in freshwater biodiversity in terms of fish species richness under future climate and potential conservation land-management schemes in the Kaskaskia River Watershed, Illinois, USA. Fish regression models were integrated to the Soil and Water Assessment Tool (SWAT) to simulate the responses of total- and game-fish species richness to four major management practices (crop rotation, cover cropping, reduced tillage, modified fertilizer application) identified as the most feasible in terms of stakeholder acceptability and environmental soundness, under 32 distinct climate projections. Results showed that fish species in the KRW are more sensitive to changes in the climate regime than to changes in the land-management practices. Specifically, the most likely percentage changes in fish species revealed a potential decline in richness in all stream orders over time with the worst impacts in the first and second order streams (-5%–-10% decade−1) due to the progressive increase in the temperatures (0.61 °C –0.92 °C decade−1) expected in the watershed. The long-term impacts on fish species richness may be inevitable if the proposed land-management alternatives were not accompanied by additional measures specifically design to protect aquatic life.

Evaluation of different peatland management scenarios to reduce GHG emissions from fires. A case study in tropical peatlands in Ogan Komering Ilir, Indonesia.

Tropical peatlands play an important role as carbon pools. Over the last decades, deforestation and degradation of Indonesian peatlands have led to a significant amount of carbon loss. Anthropogenic fires damage the ecology, the economy, and the public health of the entire region. This PhD is based on a case study in Ogan Komering Ilir (OKI) district of Indonesia. In OKI, traditional practices discard unwanted biomass with open fires, and often result in peat fires. We considered different scenarios of biomass valorisation to incite changes of practices, and to reduce peatland fires. We assessed the feasibility of converting aboveground biomass into bioenergy or other ligno-cellulosic materials.
 We estimated a business as usual (BAU) scenario by evaluating sources of emission of the current land management. We investigated potential mitigation scenarios, including biomass valorisation and peatland restoration, as alternative land management options. We evaluated the impact of these mitigation scenarios on climate change, according to their economic limitations.
 The analysis of GHG emissions in the BAU scenario shows that areas affected by fire release 70 ± 30, 140 ± 31 and 160 ± 27 Tonnes CO2-eq/ha/yr for degraded peatland, oil palm plantations and pulpwood plantations, respectively. Areas not affected by fires release 19 ± 12, 85 ± 21 and 108 ± 15 Tonnes CO2-eq/ha/yr, respectively. For the restoration scenario, we found similar GHG emissions of –0.9 Tonnes CO2-eq/ha/yr for the three land uses.
 Encouraging the biomass market in the areas where it is profitable for farmers could help reducing fire occurrences, without government investment. We instead suggest focusing government efforts on other methods such as incentive payments, or peatland restoration strategies, in the areas where biomass market is not economically viable. For the region, we find that biomass valorisation can reduce the GHG emissions by 4% to 6% compared to the BAU.
 As such, biomass valorisation is a promising alternative to current practices, potentially reducing the negative impact of fires while generating a new income for the population.

Exploring the Use of Ecosystem Services Conceptual Models to Account for the Benefits of Public Lands: An Example from National Forest Planning in the United States

A shared understanding of the benefits and tradeoffs to people from alternative land management strategies is critical to successful decision-making for managing public lands and fostering shared stewardship. This study describes an approach for identifying and monitoring the types of resource benefits and tradeoffs considered in National Forest planning in the United States under the 2012 Planning Rule and demonstrates the use of tools for conceptualizing the production of ecosystem services and benefits from alternative land management strategies. Efforts to apply these tools through workshops and engagement exercises provide opportunities to explore and highlight measures, indicators, and data sources for characterizing benefits and tradeoffs in collaborative environments involving interdisciplinary planning teams. Conceptual modeling tools are applied to a case study examining the social and economic benefits of recreation on the Ashley National Forest. The case study illustrates how these types of tools facilitate dialog for planning teams to discuss alternatives and key ecosystem service outcomes, create easy to interpret visuals that map details in plans, and provide a basis for selecting ecosystem service (socio-economic) metrics. These metrics can be used to enhance environmental impact analysis, and help satisfy the goals of the National Environmental Policy Act (NEPA), the 2012 Planning Rule, and shared stewardship initiatives. The systematic consideration of ecosystem services outcomes and metrics supported by this approach enhanced dialog between members of the Forest planning team, allowed for a more transparent process in identification of key linkages and outcomes, and identified impacts and outcomes that may not have been apparent to the sociologist who is lacking the resource specific expertise of these participants. As a result, the use of the Ecosystem Service Conceptual Model (ESCM) process may result in reduced time for internal reviews and greater comprehension of anticipated outcomes and impacts of proposed management in the plan revision Environmental Impact Statement amongst the planning team.

Evaluating runoff and sediment responses to soil and water conservation practices by employing alternative modeling approaches

Evaluating runoff and sediment responses to human activities and climate variability is crucial for prioritizing erosion hotspots and implementing appropriate land management interventions. This study evaluated the separate and combined impacts of soil and water conservation (SWC) practices, land use/land cover, and climate variability, on runoff and sediment yield (SY) using two approaches in drought-prone watersheds of northwestern Ethiopia. In the first (paired watershed) approach, runoff and SY outputs of Kecha (treated) and Laguna (untreated) watersheds were compared. In the second approach, we compared data before and after the implementation of SWC practices in the Kecha watershed. The Soil and Water Assessment Tool (SWAT) model was adopted for both untreated and treated watersheds and used to evaluate runoff and SY responses in the two approaches. Paired watershed approach results revealed that the SWC practices reduced the surface runoff in Kecha by about 28–36% and SY by about 51–68% as compared to those in Laguna. Similarly, compared with the baseline data at Kecha, the SWC practices reduced the surface runoff and SY by about 40% and 43%, respectively, corresponding to about 65–78% of the total changes brought by changes in land use/land cover and climate variability. Hence, combining the two approaches helped reasonably estimate the reduction of surface runoff and SY due to SWC practices by about 28–40% and about 43–68%, respectively, implying that SWC practices had a considerably greater effect on SY than surface runoff. The study further revealed that the untreated Laguna watershed, where >86% of the total area is categorized as the very high soil erosion severity class, should be an immediate conservation priority. The findings of this study will be vital to devise future alternative land management scenarios in these watersheds and similar agro-ecological areas elsewhere.

Modeling Climate Warming Impacts on Grain and Forage Sorghum Yields in Argentina

Sorghum is the world’s fifth major cereal in terms of production and acreage. It is expected that its growth will be affected by the increase in air temperature, an important component of global climate change. Our objective was to use the Agricultural Land Management Alternatives with Numerical Assessment Criteria (ALMANAC) model to (a) evaluate the impact of climate warming on forage and grain sorghum production in Argentina and (b) to analyze to what extent yield changes were associated with changes in water or nitrogen stress days. For model calibration, we used previous information related to the morpho-physiological characteristics of both sorghum types and several soil parameters. We then used multiyear field data of sorghum yields for model validation. Yield simulations were conducted under three possible climate change scenarios: 1, 2, and 4 °C increase in mean annual temperature. ALMANAC successfully simulated mean yields of forage and grain sorghum: root mean square error (RMSE): 2.6 and 1.0 Mg ha−1, respectively. Forage yield increased 0.53 Mg ha−1, and grain yield decreased 0.27 Mg ha−1 for each degree of increase in mean annual temperature. Yields of forage sorghum tended to be negatively associated with nitrogen stress (r = −0.94), while grain sorghum yield was negatively associated with water stress (r = −0.99). The information generated allows anticipating future changes in crop management and genetic improvement programs in order to reduce the yield vulnerability.

Climate smart agriculture opportunities for mitigating soil greenhouse gas emissions across the U.S. Corn-Belt

Widespread adoption of climate smart agriculture (CSA) has the potential to greatly mitigate agricultural greenhouse gas (GHG) emissions by increasing soil organic carbon (SOC) stocks and decreasing nitrous oxide (N2O) emissions. However, quantifying the impact of land management practices on soil GHG fluxes including CO2 and N2O is difficult due temporal and spatial variability of localized weather conditions and subfield soil properties. A process-based biogeochemistry modeling framework coupled with public soils, weather, and yield data layers was used to estimate regionally specific soil GHG reductions associated with the adoption of one or more CSA practices in maize (Zea mays L.) and soybean (Glycine max (L.) Merr.) crop production fields. Site-specific, multi-year DeNintrification-DeComposition model simulations were performed on agricultural fields within 11 U.S. Corn-Belt states that were identified to be in maize or soybean production from 2013 to 2016. Differences between modeled changes in SOC stocks to a depth of 50 cm, N2O emissions, and CH4 fluxes corresponding with alternative land management scenarios simulated across field sites were converted to a CO2 equivalent basis and spatially weighted to a county-scale to highlight regional variability. County-scale GHG reductions corresponding with a conversion from conventional tillage to no-tillage practices are estimated to be have a mean reduction potential of 1477 kg CO2e ha−1 yr−1 (SOC, N2O, and CH4 flux reductions of 945, 549, −17 kg CO2e ha−1yr−1, respectively, where a negative reduction indicates an increase in emissions.) with a standard deviation of 605 kg CO2e ha−1 yr−1. Additionally, the adoption of cover crops is predicted to provide a mean reduction of 678 kg CO2e ha−1 yr−1 (SOC, N2O, and CH4 flux reductions of 824, -173, 26.7 kg CO2e ha−1yr−1, respectively), and improved N-fertilizer timing is estimated to mitigate 413 kg CO2e ha−1 yr−1 (SOC, N2O, and CH4 flux reductions of 75, 337, 1 kg CO2e ha−1yr−1, respectively). The adoption of multiple CSA practices is estimated to have the greatest mean reduction potential of 2861 kg CO2e ha−1 yr−1 (SOC, N2O, and CH4 flux reductions of 2210, 611, 39 kg CO2e ha−1yr−1, respectively). Use of the spatially explicit subfield modeling approach based on public data provides a relatively low-cost approach for strategically targeting CSA practices to agricultural regions where adoption is most impactful.