Evaluation and selection of indicators for land degradation and desertification monitoring: methodological approach

Estimating the severity of landscape degradation in future management scenarios based on modeling the dynamics of Hoor Al-Azim International Wetland in Iran-Iraq border

Temporal and spatial changes in land cover in wetland ecosystems indicate the severity of degradation. Understanding such processes in the past, present, and future might be necessary for managing any type of development plan. Therefore, this research has monitored and analyzed the Hoor Al-Azim International Wetland to determine the orientation of its changes in various future scenarios. Wetland status modeling was conducted using developed hybrid approaches and cellular automata along with evaluating the accuracy of the modeled maps. The dynamics of the landscape were simulated using a higher accuracy approach in three scenarios-Water Conservation, Water Decreasing, and Business-as-Usual- to get the level of degradation of the wetland. The results showed that the amount of water in the wetland has decreased in all three periods, and the salt lands and vegetation have undergone drastic changes. The water bodies experienced a reduction of 148,139 ha between 1985 and 2000, followed by a decrease of 9107 ha during the 2000-2015 period. However, based on the results, these developments are expressed better by the developed hybrid approach than the CA-MC approach and are more reliable for future simulation. The figure of merit index, which assesses the hybrid model's accuracy, yielded a value of 18.12%, while the CA-MC model's accuracy was estimated at 14.42%. The assessment of degradation in hexagonal units showed the least degradation in the water conservation scenario compared with the other two scenarios in 2030.

Assessment of Irrigation Efficiency by Coupling Remote Sensing and Ground-Based Data: Case Study of Sprinkler Irrigation of Alfalfa in the Saratovskoye Zavolgie Region of Russia

Nowadays, the leading role of data from sensors to monitor crop irrigation practices is indisputable. The combination of ground and space monitoring data and agrohydrological modeling made it possible to evaluate the effectiveness of crop irrigation. This paper presents some additions to recently published results of field study at the territory of the Privolzhskaya irrigation system located on the left bank of the Volga in the Russian Federation, during the growing season of 2012. Data were obtained for 19 crops of irrigated alfalfa during the second year of their growing period. Irrigation water applications to these crops was carried out by the center pivot sprinklers. The actual crop evapotranspiration and its components being derived with the SEBAL model from MODIS satellite images data. As a result, a time series of daily values of evapotranspiration and transpiration were obtained for the area occupied by each of these crops. To assess the effectiveness of irrigation of alfalfa crops, six indicators were used based on the use of data on yield, irrigation depth, actual evapotranspiration, transpiration and basal evaporation deficit. The series of indicators estimating irrigation effectiveness were analyzed and ranked. The obtained rank values were used to analyze the similarity and non-similarity of indicators of irrigation effectiveness of alfalfa crops. As a result of this analysis, the opportunity to assess irrigation effectiveness with the help of data from ground and space-based sensors was proved.

Assessment of environmentally sensitive areas to desertification in the Blue Nile Basin driven by the MEDALUS-GEE framework

Assessing environmentally sensitive areas (ESA) to desertification and understanding their primary drivers are necessary for applying targeted management practices to combat land degradation at the basin scale. We have developed the MEditerranean Desertification And Land Use framework in the Google Earth Engine cloud platform (MEDALUS-GEE) to map and assess the ESA index at 300 m grids in the Blue Nile Basin (BNB). The ESA index was derived from elaborating 19 key indicators representing soil, climate, vegetation, and management through the geometric mean of their sensitivity scores. The results showed that 43.4%, 28.8%, and 70.4% of the entire BNB, Upper BNB, and Lower BNB, respectively, are highly susceptible to desertification, indicating appropriate land and water management measures should be urgently implemented. Our findings also showed that the main land degradation drivers are moderate to intensive cultivation across the BNB, high slope gradient and water erosion in the Upper BNB, and low soil organic matter and vegetation cover in the Lower BNB. The study presented an integrated monitoring and assessment framework for understanding desertification processes to help achieve land-related sustainable development goals.

Identifying Degraded and Sensitive to Desertification Agricultural Soils in Thessaly, Greece, under Simulated Future Climate Scenarios

The impact of simulated future climate change on land degradation was assessed in three representative study sites of Thessaly, Greece, one of the country’s most important agronomic zones. Two possible scenarios were used for estimation of future climatic conditions, which were based on greenhouse gas emissions (RCP4.5 and RCP8.5). Three time periods were selected: the reference past period 1981–2000 for comparison, and the future periods 2041–2060 and 2081–2100. Based on soil characteristics, past and future climate conditions, type of land uses, and land management prevailing in the study area, the Environmentally Sensitive to desertification Areas (ESAs) were assessed for each period using the MEDALUS-ESAI index. Soil losses derived by water and tillage erosion were also assessed for the future periods using existing empirical equations. Furthermore, primary soil salinization risk was assessed using an algorithm of individual indicators related to the natural environment or socio-economic characteristics. The obtained data by both climatic scenarios predicted increases in mean maximum and mean minimum air temperature. Concerning annual precipitation, reductions are generally expected for the three study sites. Desertification risk in the future is expected to increase in comparison to the reference period. Soil losses are estimated to be more important in sloping areas, due especially to tillage erosion in at least one study site. Primary salinization risk is expected to be higher in one study site and in soils under poorly drainage conditions.

Assessing the Vulnerability to Land Degradation of (Not Only) Rural Landscapes Using the ESAI Index

Determining the vulnerability of land to degradation is a crucial factor enabling policy makers to take targeted actions. The main aim of this work was to determine vulnerability to land degradation using the Environmentally Sensitive Area Index (ESAI) in the territory of 206 municipalities with extended power (MEPs), regions (NUTS 3) and in the Czech Republic (CR). The other two aims were found out i) whether land degradation is affected by land use characterized by landscape types according to Löw et al. (2006) and ii) whether land degradation occurred in larger territorial units (regions) or scattered across the CR (in individual isolated MEPs). The Environmentally Sensitive Area (ESA) method assesses the vulnerability of an area to land degradation using a composite index containing indicators divided into four thematic groups: human activity pressure and management intensity, vegetation cover and vegetation quality, climate, and soil in the assessed area. The ESAI index is expressed on a semi-quantitative scale ranging from the lowest levels of degradation (land not affected and land potentially affected by degradation) to the highest level of degradation (land at high risk). Most MEPs with a share of more than 70 % of their area were in the category "moderately critical areas" at risk of land degradation were located in the Central Bohemia region (15 MEPs) and in the South Moravia region (14 MEPs). For the whole territory of the Czech Republic, 51 % of the territory was found to be critically vulnerable to land degradation, and 38 % of the republic area was vulnerable to land degradation. Vulnerability to land degradation was strongly influenced by the landscape type. Almost all MEPs with a predominantly agricultural landscapes were critically vulnerable to land degradation, as were about half of the MEPs in the forest-agricultural and urban landscapes and only a few MEPs in the forest landscapes. Given the selected indicators, the MEP seems to be the appropriate smallest administrative unit to assess vulnerability to land degradation in the Czech Republic. The map of individual ESAI values can be viewed free of charge online at http://www.imalbes.cz/vysledek.php. We are currently preparing a proposal for appropriate measures to prevent and reduce land degradation throughout the territory of the Czech Republic, and our proposals are coordinated with representatives of the MEPs and regions.

Ultimately, What is Forest Landscape Restoration in Practice? Embodiments in Sub-Saharan Africa and Implications for Future Design

Forest landscape restoration (FLR) is gaining ground as a novel, holistic approach to sustainable environmental management across developing countries. In sub-Saharan Africa, 30 countries have joined the African Forest Landscape Restoration Initiative to advance FLR goals. Although conceptually compelling, and despite efforts articulating initial implementation guidelines, divergent discourses and interpretations confound FLR translation into practice. We propose a characterization of FLR in practice using insights from political ecology; principles of ecological restoration and landscape sustainability science; and the philosophy, principles, and objectives of the FLR paradigm. Our qualitative analysis further draws on secondary data and insights from participant observation during FLR-related workshops. We build and organize the FLR characterization around answers to ten questions: why restoration; what purpose; for what desired outcomes; where (location and land uses); what spatial extent and scale(s); who; which techniques; how (approach/strategy); when and how long; and how much to achieve. We then assess early FLR strategic priorities for interventions across nine African countries and analyze five selected actual projects to illustrate use of the proposed FLR characterization framework. The illustrative characterization of both planned interventions and actual projects does not reflect all the proposed characteristics of FLR in practice. Missing features include the initial biophysical condition, the desired target ecosystem state, and evaluation dimensions, and ill-articulated aspects include cross-sectoral integrations. We contend that any significant differences between FLR conceptualization, including its principles, and the practical manifestations can undermine coherence, the value that the FLR approach adds, and its wider adoption. The proposed characterization of FLR in practice contributes to scholarly attempts to realign FLR conceptual philosophy, principles, and rhetoric to its practical manifestations in different contexts, and can inform future design of FLR undertakings for more inclusive landscape governance.

A long-term spatiotemporal analysis of biocrusts across a diverse arid environment: The case of the Israeli-Egyptian sandfield

Spatiotemporal data can be analyzed using spatial, time-series, and machine learning algorithms to extract regional biocrust trends. Analyzing the spatial trends of biocrusts through time, using satellite imagery, may improve the quantification and understanding of their change drivers. The current work strives to develop a unique framework for analyzing spatiotemporal trends of the spectral Crust Index (CI), thus identifying the drivers of the biocrusts' spatial and temporal patterns. To fulfill this goal, CI maps, derived from 31 annual Landsat images, were analyzed by applying advanced statistical and machine learning algorithms. A comprehensive overview of biocrusts' spatiotemporal patterns was achieved using an integrative approach, including a long-term analysis, using the Mann-Kendall (MK) statistical test, and a short-term analysis, using a rolling MK with a window size of five years. Additionally, temporal clustering, using the partition around medoids (PAM) algorithm, was applied to model the spatial multi-annual dynamics of the CI. A Granger Causality test was then applied to quantify the relations between CI dynamics and precipitation. The findings show that 88.7% of pixels experienced a significant negative change, and only 0.5% experienced a significant positive change. A strong association was found in temporal trends among all clusters (0.67 ≤ r ≤ 0.8), signifying a regional effect due to precipitation levels (p < 0.05 for most clusters). The biocrust dynamics were also locally affected by anthropogenic factors (0.58 > CI > 0.64 and 0.64 > CI > 0.71 for strongly and weakly affected regions, respectively). A spatiotemporal analysis of a series of spaceborne images may improve conservation management by evaluating biocrust development in drylands. The suggested framework may also by applied to various disciplines related to quantifying spatial and temporal trends.

Research Progress of Desertification and Its Prevention in Mongolia

Mongolia is a globally crucial region that has been suffering from land desertification. However, current understanding on Mongolia’s desertification is limited, constraining the desertification control and sustainable development in Mongolia and even other parts of the world. This paper studied spatiotemporal patterns, driving factors, mitigation strategies, and research methods of desertification in Mongolia through an extensive review of literature. Results showed that: (i) remote sensing monitoring of desertification in Mongolia has been subject to a relatively low spatial resolution and considerable time delay, and thus high-resolution and timely data are needed to perform a more precise and timely study; (ii) the contribution of desertification impacting factors has not been quantitatively assessed, and a decoupling analysis is desirable to quantify the contribution of factors in different regions of Mongolia; (iii) existing desertification prevention measures should be strengthened in the future. In particular, the relationship between grassland changes and husbandry development needs to be considered during the development of desertification prevention measures; (iv) the multi-method study (particularly interdisciplinary approaches) and desertification model development should be enhanced to facilitate an in-depth desertification research in Mongolia. This study provides a useful reference for desertification research and control in Mongolia and other regions of the world.

Evaluating quality of soils formed on basement complex rocks in Kaduna State, northern Guinea savanna of Nigeria

A few investigations have been done regarding the soil quality index (SQI) for various locations, soil types, and states. Still, little has been reported regarding SQI for both surface and control sections, especially for the Northern Guinea Savanna of Nigeria. Due to the subsurface property pedogenic influence on soil function, it is crucial to assess SQI using surface and subsurface properties as both properties influence soil productivity. We investigated the potentials of choosing a minimum data set for soil quality indicators and assess soil quality (SQ), using both surface and entire soil pedon data for the soils on the basement complexes. Both additive and weighted soil quality indices and different scoring methods (linear and non-linear) were used in evaluating SQ. Out of the twenty-three soil properties subjected to PCA, eight indicators (TEB, clay, silt, K, EA, EC, BD, and Fe) were selected as the minimum data set (MDS). There was not much difference in the calculated soil quality using the non-linear additive (SQI-NLA), linear additive (SQI-LA), linear weighted (SQI-LW), and non-linear weighted (SQI-NLW) for the soils as they were all rated low (SQI < 0.55). The estimated SQI for the control section had relatively higher values than the surface soil, thus suggesting the need to incorporate both surface and entire soil profile properties in assessing SQ as both are important in integrating the relationship between soil properties and management goals which eventually provides complete information that affects the production of crops.

Critical range of soil organic carbon in southern Europe lands under desertification risk

Soil quality is fundamental for ecosystem long term functionality, productivity and resilience to current climatic changes. Despite its importance, soil is lost and degraded at dramatic rates worldwide. In Europe, the Mediterranean areas are a hotspot for soil erosion and land degradation due to a combination of climatic conditions, soils, geomorphology and anthropic pressure. Soil organic carbon (SOC) is considered a key indicator of soil quality as it relates to other fundamental soil functions supporting crucial ecosystem services. In the present study, the functional relationships among SOC and other important soil properties were investigated in the topsoil of 38 sites under different land cover and management, distributed over three Mediterranean regions under strong desertification risk, with the final aim to define critical SOC ranges for fast loss of important soil functionalities. The study sites belonged to private and public landowners seeking to adopt sustainable land management practices to support ecosystem sustainability and productivity of their land. Data showed a very clear relationship between SOC concentrations and the other analyzed soil properties: total nitrogen, bulk density, cation exchange capacity, available water capacity, microbial biomass, C fractions associated to particulate organic matter and to the mineral soil component and indirectly with net N mineralization. Below 20 g SOC kg^-1, additional changes of SOC concentrations resulted in a steep variation of all the analyzed soil indicators, an order of magnitude higher than the changes occurring between 50 and 100 g SOC kg^-1 and 3-4 times the changes observed at 20-50 g SOC kg^-1. About half of the study sites showed average SOC concentration of the topsoil centimetres <20 g SOC kg^-1. For these areas the level of SOC might hence be considered critical and immediate and effective recovery management plans are needed to avoid complete land degradation in the next future.

Monitoring land use and soil salinity changes in coastal landscape: a case study from Senegal

Soil salinity is a major issue causing land degradation in coastal areas. In this study, we assessed the land use and soil salinity changes in Djilor district (Senegal) using remote sensing and field data. We performed land use land cover changes for the years 1984, 1994, 2007, and 2017. Electrical conductivity was measured from 300 soil samples collected at the study area; this, together with elevation, distance to river, Normalized Difference Vegetation Index (NDVI), Salinity Index (SI), and Soil-Adjusted Vegetation Index (SAVI), was used to build the salinity model using a multiple regression analysis. Supervised classification and intensity analysis were applied to determine the annual change area and the variation of gains and losses. The results showed that croplands recorded the highest gain (17%) throughout the period 1984-2017, while forest recorded 3%. The fastest annual area of change occurred during the period 1984-1994. The salinity model showed a high potential for mapping saline areas (R² = 0.73 and RMSE = 0.68). Regarding salinity change, the slightly saline areas (2 < EC < 4 dS/m) increased by 42% whereas highly saline (EC > 8 dS/m) and moderately saline (4 < EC < 8 dS/m) areas decreased by 23% and 26%, respectively, in 2017. Additionally, the increasing salt content is less dominant in vegetated areas compared with non-vegetated areas. Nonetheless, the highly concentrated salty areas can be restored using salt-resistant plants (e.g., Eucalyptus sp., Tamarix sp.). This study gives more insights on land use planning and salinity management for improving farmers' resilience in coastal regions.

Site suitability analysis for potential agricultural land with spatial fuzzy multi-criteria decision analysis in regional scale under semi-arid terrestrial ecosystem

The main purpose of this study is to identify suitable potential areas for agricultural activities in the semi-arid terrestrial ecosystem in the Central Anatolia Region. MCDA was performed in fuzzy environment integrated with GIS techniques and different geostatistical interpolation models, which was chosen as the basis for the present study. A total of nine criteria were used, as four terrain properties and five soil features to identify potential sites suitable for agriculture lands in Central Anatolia which covers approximately 195,012.7 km². In order to assign weighting value for each criterion, FAHP approach was used to make sufficiently sensitive levels of importance of the criteria. DEM with 10 m pixel resolution used to determine the height and slope characteristics, digital geology and soil maps, CORINE land use/land cover, long-term meteorological data, and 4517 soil samples taken from the study area were used. It was identified that approximately 30.7% of the total area (59,921.8 ha) is very suitable and suitable for potential agriculture activities on S1 and S2 levels, 42.7% of the area is not suitable for agricultural uses, and only 27% of the area is marginally suitable for agricultural activities. Besides, it was identified that 34.8% of the area is slightly suitable.

A method for calculating land degradation neutrality

Land degradation neutrality (LDN) has been introduced by United Nations Convention to Combat Desertification (UNCCD). Studies of LDN has been encouraged worldwide by UNCCD to compact land degradation. The LDN aims to maintain or even improve the land quality over time and therefore, it envisages quantifying the balance between the gains and losses within a given land type and scale. In this regard, a mathematical model was developed to calculate and redress land degradation. The calculations showed that the model is stable within the values of quality indices (1 and 2) and correlation coefficients (0 and 1).•

The model calculates a proxy parameter as a representative of land quality using a set of land quality indices and correlation coefficients between those indices.

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The model compares the values for proxy variable for initial and degraded conditions, and calculates the gains needed to equalize the two values.

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The model is independent of scale and it is easy to use.

Desertification Risk and Rural Development in Southern Europe: Permanent Assessment and Implications for Sustainable Land Management and Mitigation Policies

The United Nations Convention to Combat Desertification defines ‘land degradation’ as a reduction or loss of the biological and economic productivity resulting from land-use mismanagement, or a combination of processes, such as soil erosion, deterioration of soil properties, and loss of natural vegetation and biodiversity. Land degradation is hence an interactive process involving multiple factors, among which climate, land-use, economic dynamics and socio-demographic forces play a key role. Especially in the Mediterranean basin, joint biophysical and socioeconomic factors shape the intrinsic level of vulnerability of both natural and agricultural land to degradation. The interplay between biophysical and socioeconomic factors may become extremely complex over time and space, resulting in specific patterns of landscape deterioration. This paper summarizes theoretical expectations and empirical knowledge in the field of soil and landscape degradation in Mediterranean Europe, evidencing the intimate relationship between agriculture and socio-demographic factors of growth (or decline) of rural areas. Understanding spatio-temporal trends of each factor underlying land degradation and the related background context is a key tool in the assessment of the spatial distribution of vulnerable and critical land to degradation. Empirical results of a permanent monitoring of land degradation contributes to delineate more effective conservation policies through identification of target areas requiring specific actions for biodiversity and landscape protection. With increasing human pressure on rural environments, a diachronic evaluation of patterns and processes of land degradation reveals particularly appropriate in a both positive and normative perspective, prefiguring new actions for soil conservation and landscape valorization under global change.

Linking fire and the United Nations Sustainable Development Goals

Fire is a ubiquitous natural disturbance that affects 3-4% of the Earth's surface each year. It is a tool used by humans for land clearing and burning of agricultural wastes. The United Nations Sustainable Development Goals (SDGs) do not explicitly mention fire, though many of the Goals are affected by the beneficial and adverse consequences of fires on ecosystem services. There are at least three compelling reasons to include a fire perspective in the implementation of the United Nations Sustainable Development Goals. The first reason relates to the stated vision of the United Nations 2030 Agenda to protect the environment. In order to achieve environmental protection during sustainable development activities, it is necessary to understand and plan for the effects of disturbances, in this case fire, on ecosystem services. The second reason is that fires produce emissions with regional and global impacts on air quality and rainfall patterns. Fires contribute to global warming though the release greenhouse gases, primarily CO₂, and black carbon, identified as a SLCP (short-lived climate pollutant). The third reason is that fire is one of several complex processes that lead to land degradation across the globe. Opportunities exist to incorporate a fire perspective into sustainable development projects or approaches. Two examples are highlighted here. Transdisciplinary communication and collaboration are needed to address the complex issues related to fire, and to climate and land use change.

Monitoring land sensitivity to desertification in Central Asia: Convergence or divergence?

In Central Asia, desertification risk is one of the main environmental and socioeconomic issues; thus, monitoring land sensitivity to desertification is an extremely urgent issue. In this study, the combination of convergence patterns and desertification risk is advanced from a technical perspective. Furthermore, the environmentally sensitive area index (ESAI) method was first utilized to monitor the risk of desertification in Central Asia. In the study, the spatial and temporal patterns of desertification risk were illustrated from 1992 to 2015 using fourteen indicators, including vegetation, climate, soil and land management quality. The ESAI spatial convergence across administrative subdivisions was explored for three time intervals: 1992-2000, 2000-2008 and 2008-2015. The results indicated that nearly 13.66% of the study area fell into the critical risk of desertification from 1992 to 2008. However, the risk of desertification has improved since 2008, with critical classifications decreasing by 19.70% in 2015. According to the mutation year detection in the ESAI, 25.89% of the pixels with mutation years from 1992 to 2000 were identified, and this value was higher than that during the other time periods. The convergence analysis revealed that the desertification risk for 1992-2000 tended to diverge with a positive convergence coefficient of 0.13 and converge over the 2000-2008 and 2008-2015 time periods with negative convergence coefficients of -0.534 and -0.268, respectively. According to the spatial convergence analysis, we found that the divergence patterns in northern Central Asia from 1992 to 2000 resulted from the effects of the Soviet Union collapse: cropland abandonment in northern Kazakhstan and rangeland abandonment in Tajikistan, Kyrgyzstan and eastern Kazakhstan. In contrast, most areas from 2000 to 2008 experienced increased sensitivity to desertification with the convergence pattern caused by decreased precipitation, especially in northern Central Asia. However, convergence patterns were found in most regions for 2008-2015 with regard to augmented precipitation, which resulted in decreased sensitivity to desertification. Moreover, the low sensitivity areas were more likely to converge under increased precipitation. In this region, the findings of our study suggested that spatial convergence and divergence acted as related predictors of climate change and human activities, respectively. Thus, the ESAI convergence analysis was considered to provide an early warning of potential desertification.

Combating Land Degradation and Desertification: The Land-Use Planning Quandary

Land-use planning (LUP), an instrument of land governance, is often employed to protect land and humans against natural and human-induced hazards, strengthen the resilience of land systems, and secure their sustainability. The United Nations Convention to Combat Desertification (UNCCD) underlines the critical role of appropriate local action to address the global threat of land degradation and desertification (LDD) and calls for the use of local and regional LUP to combat LDD and achieve land degradation neutrality. The paper explores the challenges of putting this call into practice. After presenting desertification and the pertinent institutional context, the paper examines whether and how LDD concerns enter the stages of the LUP process and the issues arising at each stage. LDD problem complexity, the prevailing mode of governance, and the planning style endorsed, combined with LDD awareness, knowledge and perception, value priorities, geographic particularities and historical circumstances, underlie the main challenges confronting LUP; namely, adequate representation of LDD at each stage of LUP, conflict resolution between LDD-related and development goals, need for cooperation, collaboration and coordination of numerous and diverse actors, sectors, institutions and policy domains from multiple spatial/organizational levels and uncertainty regarding present and future environmental and socio-economic change. In order to realize the integrative potential of LUP and foster its effectiveness in combating LDD at the local and regional levels, the provision of an enabling, higher-level institutional environment should be prioritized to support phrοnetic-strategic integrated LUP at lower levels, which future research should explore theoretically, methodologically and empirically.

Trichoderma Biofertilizer Links to Altered Soil Chemistry, Altered Microbial Communities, and Improved Grassland Biomass

In grasslands, forage and livestock production results in soil nutrient deficits as grasslands typically receive no nutrient inputs, leading to a loss of grassland biomass. The application of mature compost has been shown to effectively increase grassland nutrient availability. However, research on fertilization regime influence and potential microbial ecological regulation mechanisms are rarely conducted in grassland soil. We conducted a two-year experiment in meadow steppe grasslands, focusing on above- and belowground consequences of organic or Trichoderma biofertilizer applications and potential soil microbial ecological mechanisms underlying soil chemistry and microbial community responses. Grassland biomass significantly (p = 0.019) increased following amendment with 9,000 kg ha⁻¹ of Trichoderma biofertilizer (composted cattle manure + inoculum) compared with other assessed organic or biofertilizer rates, except for BOF3000 (fertilized with 3,000 kg ha⁻¹ biofertilizer). This rate of Trichoderma biofertilizer treatment increased soil antifungal compounds that may suppress pathogenic fungi, potentially partially responsible for improved grassland biomass. Nonmetric multidimensional scaling (NMDS) revealed soil chemistry and fungal communities were all separated by different fertilization regime. Trichoderma biofertilizer (9,000 kg ha⁻¹) increased relative abundances of Archaeorhizomyces and Trichoderma while decreasing Ophiosphaerella. Trichoderma can improve grassland biomass, while Ophiosphaerella has the opposite effect as it may secrete metabolites causing grass necrosis. Correlations between soil properties and microbial genera showed plant-available phosphorus may influence grassland biomass by increasing Archaeorhizomyces and Trichoderma while reducing Ophiosphaerella. According to our structural equation modeling (SEM), Trichoderma abundance was the primary contributor to aboveground grassland biomass. Our results suggest Trichoderma biofertilizer could be an important tool for management of soils and ultimately grassland plant biomass.

Model Prediction of Secondary Soil Salinization in the Keriya Oasis, Northwest China

Significant anthropogenic and biophysical changes have caused fluctuations in the soil salinization area of the Keriya Oasis in China. The Driver-Pressure-State-Impact-Response (DPSIR) sustainability framework and Bayesian networks (BNs) were used to integrate information from anthropogenic and natural systems to model the trend of secondary soil salinization. The developed model predicted that light salinization (vegetation coverage of around 15–20%, soil salt 5–10 g/kg) of the ecotone will increase in the near term but decelerate slightly in the future, and that farmland salinization will decrease in the near term. This trend is expected to accelerate in the future. Both trends are attributed to decreased water logging, increased groundwater exploitation, and decreased ratio of evaporation/precipitation. In contrast, severe salinization (vegetation coverage of around 2%, soil salt ≥20 g/kg) of the ecotone will increase in the near term. This trend will accelerate in the future because decreased river flow will reduce the flushing of severely salinized soil crust. Anthropogenic factors have negative impacts and natural causes have positive impacts on light salinization of ecotones. In situations involving severe farmland salinization, anthropogenic factors have persistent negative impacts.

Albedo indicating land degradation around the Badain Jaran Desert for better land resources utilization

Surface albedo is an easy access parameter in reflecting the status of both human disturbed soil and indirectly influenced area, whose characteristic is an important indicator in sustainable development under the background of global climate change. In this study, we employed meteorological data, MODIS 8-day BRDF/Albedo and LAI products from 2000 to 2014 to show the amelioration and mechanism around the Badain Jaran Desert. Results showed that the human-dominated afforestation activities significantly increased the leaf area index (LAI) in summer and autumn. Lower reflectance at visible band was sensed inside the desert compared with the ecozone and the lowest albedo at forested area. The contribution of soil and vegetation reflectance to surface albedo determined the linear sensitivity of albedo to LAI variation. Decreased albedo dominated the spatial-temporal pattern of the Badain Jaran Desert. This study suggested that surface albedo can be regarded as a useful index in indicating the change process and evaluating the sustainable development of biological management around the Badain Jaran Desert.

Application of poultry processing industry waste: a strategy for vegetation growth in degraded soil

The disposal of poultry processing industry waste into the environment without proper care, can cause contamination. Agricultural monitored application is an alternative for disposal, considering its high amount of organic matter and its potential as a soil fertilizer. This study aimed to evaluate the potential of poultry processing industry waste to improve the conditions of a degraded soil from a desertification hotspot, contributing to leguminous tree seedlings growth. The study was carried out under greenhouse conditions in a randomized blocks design and a 4 × 2 factorial scheme with five replicates. The treatments featured four amounts of poultry processing industry waste (D1 = control 0 kg ha(-1); D2 = 1020.41 kg ha(-1); D3 = 2040.82 kg ha(-1); D4 = 4081.63 kg ha(-1)) and two leguminous tree species (Mimosa caesalpiniaefolia Benth and Leucaena leucocephala (Lam.) de Wit). The poultry processing industry waste was composed of poultry blood, grease, excrements and substances from the digestive system. Plant height, biomass production, plant nutrient accumulation and soil organic carbon were measured forty days after waste application. Leguminous tree seedlings growth was increased by waste amounts, especially M. caesalpiniaefolia Benth, with height increment of 29.5 cm for the waste amount of 1625 kg ha(-1), and L. leucocephala (Lam.) de Wit, with maximum height increment of 20 cm for the waste amount of 3814.3 kg ha(-1). M. caesalpiniaefolia Benth had greater initial growth, as well as greater biomass and nutrient accumulation compared with L. leucocephala (Lam.) de Wit. However, belowground biomass was similar between the evaluated species, resulting in higher root/shoot ratio for L. leucocephala (Lam.) de Wit. Soil organic carbon did not show significant response to waste amounts, but it did to leguminous tree seedlings growth, especially L. leucocephala (Lam.) de Wit. Poultry processing industry waste contributes to leguminous tree seedlings growth, indicating that it can be part of a long-term strategy to increase soil organic carbon in degraded soil from a desertification hotspot.

Evaluation and selection of indicators for land degradation and desertification monitoring: types of degradation, causes, and implications for management

Indicator-based approaches are often used to monitor land degradation and desertification from the global to the very local scale. However, there is still little agreement on which indicators may best reflect both status and trends of these phenomena. In this study, various processes of land degradation and desertification have been analyzed in 17 study sites around the world using a wide set of biophysical and socioeconomic indicators. The database described earlier in this issue by Kosmas and others (Environ Manage, 2013) for defining desertification risk was further analyzed to define the most important indicators related to the following degradation processes: water erosion in various land uses, tillage erosion, soil salinization, water stress, forest fires, and overgrazing. A correlation analysis was applied to the selected indicators in order to identify the most important variables contributing to each land degradation process. The analysis indicates that the most important indicators are: (i) rain seasonality affecting water erosion, water stress, and forest fires, (ii) slope gradient affecting water erosion, tillage erosion and water stress, and (iii) water scarcity soil salinization, water stress, and forest fires. Implementation of existing regulations or policies concerned with resources development and environmental sustainability was identified as the most important indicator of land protection.

From framework to action: the DESIRE approach to combat desertification

It has become increasingly clear that desertification can only be tackled through a multi-disciplinary approach that not only involves scientists but also stakeholders. In the DESIRE project such an approach was taken. As a first step, a conceptual framework was developed in which the factors and processes that may lead to land degradation and desertification were described. Many of these factors do not work independently, but can reinforce or weaken one another, and to illustrate these relationships sustainable management and policy feedback loops were included. This conceptual framework can be applied globally, but can also be made site-specific to take into account that each study site has a unique combination of bio-physical, socio-economic and political conditions. Once the conceptual framework was defined, a methodological framework was developed in which the methodological steps taken in the DESIRE approach were listed and their logic and sequence were explained. The last step was to develop a concrete working plan to put the project into action, involving stakeholders throughout the process. This series of steps, in full or in part, offers explicit guidance for other organizations or projects that aim to reduce land degradation and desertification.