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Catastrophic shifts are known to pose a serious threat to ecology, and a reliable set of early warning indicators is desperately needed. However, the tools suggested so far have two problems. First, they cannot discriminate between a smooth transition and an imminent irreversible shift. Second, they aimed at predicting the tipping point where a state loses its stability, but in noisy spatial system the actual transition occurs when an alternative state invades. Here we suggest a cluster tracking technique that solves both problems, distinguishing between smooth and catastrophic transitions and to identify an imminent shift in both cases. Our method may allow for the prediction, and thus hopefully the prevention of such transitions, avoiding their destructive outcomes., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

In order to clarify the response relationship between rocky desertification and land use under different lithology background in karst area. We obtained the land use distribution in 2005, 2010 and 2015 by using supervised classification, and then carried out superimposed analysis with the rocky desertification and lithology data in the same period. The result shows that woodland and shrubbery are mainly distributed on limestone interbedded with clastic rock, with an area of approximately 51.73 km2. Grasslands and arable land are mainly distributed on continuous limestone and limestone interbedded with clastic rock. Rocky desertification area in the limestone interbedded with clastic rock is the largest, and extremely severe rocky desertification (ESKRD) of 6.70 km2, due to the difference of lithologic types. Different levels of rocky desertification are correlated with different land use types and lithology types. The type of rocky desertification in forest land is mainly light rocky desertification (LKRD), contributing more than 40% of the area of rocky desertification, while the type of severe rocky desertification (SKRD) is mainly distributed in cultivated land, contributing more than 20% of the area of rocky desertification. In addition, due to the limited available resources in karst mountain areas, rocky desertification caused by human activities may also occur on non-carbonate rocks. We have emphasized the quantitative analysis of the response relationship between rocky desertification and land use at spatial grid scale, which is of great value for the location and treatment of rocky desertification in karst areas. [ABSTRACT FROM AUTHOR]

Abstract Background Desertification is the most severe environmental problem in arid and semi-arid regions and has caused great economic loss every year. However, artificial sand fixation barriers function on sand fixation for only 10–20 years. Searching for a native species with long-term sand fixation effect and strong environmental adaptive capacity, and low water consumption is needed. In this study, we investigated the environmental adaption and sand fixation effect of a grass from Poaceae family (Psammochloa villosa) that is indigenous to the desert of Northwest China. Results The results showed that P. villosa has a streamlined leaf form, strong mechanical strength, and flexibility to adapt to wind. Leaf curling of P. villosa under drought decreased water loss rate through decreased evaporation area to adapt to drought. Significant negative relationship between adventitious root length and horizontal root burial depth indicates that adventitious roots help P. villosa absorb water and nutrients from soil under shallow sand burial condition, which enables P. villosa to adapt to different sand burial conditions. P. villosa fixed sand dunes through the distribution of the population at the top of the dune and the vertical relationship between the direction of windblown sand and the direction of growth of P. villosa, which stopped the expansion of the dune. Conclusions Growth characteristics of wind and drought tolerant leaf traits and adventitious roots under sand burial indicate that P. villosa is well adapted to dry sandy desert conditions and burial by sand. The distribution of the P. villosa population on the sand dune is a “brake” on its expansion. These findings provide new insight for active sand dune fixation and desertification control using native grass in the desertified regions.

Words and terms evoke responses in us, independently of their original meaning. Precise language matters because terminology can affect conservation. For example, current deforestation rates put the Amazon in the spotlight of global conservation, particularly after the “savannization of the Amazon” was proposed. This term associates cleared or degraded forests with savannas, reinforcing prejudices against natural savannas. The Cerrado is the world’s largest and richest savanna, but receives less conservation attention and resources. Firstly, we showed a multisector Cerrado neglect: number of protected areas, non-governmental organizations, academic human resources, and companies were larger in the Amazon, but deforested area was proportionally smaller. Secondly, we analyzed the academic use of “savannization of the Amazon.” In all 481 studies using this term, human action was implied, and most meant that degraded Amazon does not become old-growth savanna. We propose abandoning the use of “savannization of the Amazon”, promoting the support and attention the Cerrado needs.

Ecological resilience, defined as the amount of disturbance that a system can withstand before it shifts into an alternative stable state, is a fundamental property of ecosystems and other biological systems. By the end of the 1980s, unregulated livestock production and overgrazing resulted in the desertification of rangelands in Kalmykia (southern Russia). In the early 1990s, a drastic and considerable reduction in livestock numbers led to vegetation restoration and steppification of rangelands. In the last decade, the increase in grazing impact has launched a new process of desertification. We studied the population dynamics of the keystone rodent species (the midday gerbil – Meriones meridianus, the tamarisk gerbil – M. tamariscinus and the social vole – Microtus socialis) to identify general patterns and species-specific features of their response to the landscape transformations. We compared the speed and the strength of the species responses to the landscape changes, the stability of regimes of population dynamics, and the threshold effects when they change. Under landscape changes from desert to steppe and back to desert, the population dynamics of all studied rodent species demonstrated non-stationarity, threshold step-like transitions between stable regimes and the synchronicity of tipping points caused by weather anomalies. The general patterns of non-stationary dynamics were similar across different species. However, species differed in the dynamic population characteristics, such as the duration of the regimes, the amplitude of step-like shifts between them, and the overall resistance of populations to environmental changes (resilience). Species-specific differences in dynamic patterns of response are consistent with their ecological specialization and preferences: the higher the specialization, the shorter the stable dynamic regimes, the greater the amplitude of abrupt shifts between them, and the less the overall population resistance to landscape changes.

Desertification is one of the most significant environmental and social challenges globally. Monitoring desertification dynamics and quantitatively identifying the contributions of its driving factors are crucial for land restoration and sustainable development. This study develops a standardized methodological framework that combines desertification dynamics with driving mechanisms at the pixel level, applied to northern China from 2000 to 2020. Using multisource data and employing the Time Series Segmentation and Residual Trend analysis (TSS-RESTREND) method alongside geographical detector, we quantitatively assessed desertification reversion, expansion, and abrupt change processes, along with the impacts and interactions of natural and human factors were quantitatively assessed. Over the past two decades, the proportion of desertified land decreased by 5.60%. Notably, 32.88% of the study area experienced significant desertification reversion, while only 5.86% underwent expansion. Abrupt changes in both reversed and expanding areas were observed, primarily in the central and western regions, with these changes concentrated in the periods of 2009–2011 and 2014–2016. The impacts of various factors in different sub-regions exhibited significant spatial heterogeneity. Increased precipitation, temperature, and evapotranspiration contributed to reversion in the western area, while decreased wind speed influenced the eastern area. Additionally, decreased population density and afforestation activities also promoted desertification reversion. In contrast, decreased precipitation and increased temperature contributed to expansion in the western and eastern areas, respectively, with increased population density exacerbating this process. Overall, the interactions between natural and human factors were enhanced. Future desertification control and ecological engineering planning should focus on the coupling effects of different driving factors and relevant abrupt vegetation changes.

Abstract Vegetation restoration in dryland regions may be a powerful way to control desertification and promote local habitat recovery. In these artificial revegetation systems, ecosystem processes and functioning are strongly determined by nitrogen (N) availability, while soil inorganic N (SIN) is the major available N form and is absorbed as a main N source for plants. However, SIN dynamics, their influencing factors, and their relative importance to the ecosystem of these N‐limited systems are not well understood. A field investigation was conducted to examine the monthly variations in SIN and its response to planting age and vegetation type in a typical artificial sand‐fixing system in northwestern China. The SIN content in topsoil (0–20 cm) during the growing season ranged from 7.10 to 95.65 mg kg−1, with a mean value of 27.14 mg kg−1. Soil nitrate N had a dominant role in determining SIN monthly dynamics, which showed a fluctuating trend with two peak values in early July and late August. SIN showed a significant increasing trend with the planting age of sand‐fixing vegetation, and it was highest for Nitraria sphaerocarpa (55.66 ± 5.76 mg kg−1), followed by Haloxylon ammodendron (29.81 ± 3.47 mg kg−1) and interspace (11.39 ± 1.13 mg kg−1). SIN displayed a hump‐shaped relationship with air temperature (R2 = 0.96, p

Desertification poses a serious threat to ecosystem health, and with global changes, the variability and uncertainty of ecological functions in semi-arid alpine regions are increasing. A pressing issue is quantifying how desertification affects the soil system functions in these areas. However, empirical evidence is still lacking in exploring the interaction between desertification degradation gradients and soil functions under natural conditions by coupling soil physicochemical properties, soil microbiota, and vegetation. For this purpose, we conducted a survey sampling of soil and vegetation at five sites with no, light, moderate, severe and extremely severe desertification in Qinghai Area of Qilian Mountains National Park, China. We introduced a new concept soil health stability (SHS) to represent the actual health status of soil systems in semi-arid alpine regions and assessed the impact of desertification on this stability. We observed that the intensification of desertification has led to a significant decrease in soil organic matter, relative abundance of soil microorganisms, and plant factors. The contributions of plant factors and soil microbiota to SHS showed a negative correlation with the degradation gradient. SHS varied across different degradation gradients, rather than following a single linear relationship, with a relatively rapid decline in the transition from non-desertification to moderate desertification. Our work emphasizes that the coupled contributions of soil physicochemical properties, soil microbiota, and vegetation to SHS. It calls for intensified prevention and treatment of mild and moderate desertification, while providing new methods and deeper scientific understanding for accurately evaluating soil system functions in semi-arid alpine regions.

Dust is one of the major crises in the Middle East. In recent years, the frequency and intensity of this crisis in the region has increased and this has increased the need to study this phenomenon. In this article, we have studied the temporal and spatial changes of the dust storm phenomenon in Iran, Khuzestan (south-west) in the period 2000 to 2018. For this purpose, ground dust data and horizontal visibility and (Aerosol Optical Depth( data of MODIS satellite have been used. The AOD Optical Visibility Index has been declining from 2003 to 2007 and then increasing again. In general, we can see a gradual but increasing trend in the AOD index in the study area, from an average of 0.35 at the beginning of the period to nearly 0.6 at the end of the period, which indicates the predominance of dust storms in the region. The relationship between dust and climatic parameters was also examined. In terms of external storms, precipitation had a significant (P

Owing to the combined effects of climate change and human activities, the type of desertification in the arid regions of Asia has undergone profound changes, and the problem of desertification has become increasingly prominent. To help address this problem, this study clarifies the transformation trends and characteristics of desertification types across Asia and discusses key areas for desertification prevention and control. Based on a series of Landsat satellite images, combined with the classification method of the desertification degree and a machine learning model, the desertification types, trends, and conversion degrees in the arid regions of Asia were systematically evaluated. In addition, the impact mechanism of climate change on the conversion between desertification types was evaluated. The primary results were as follows: (1) Various desertification types in the arid areas of Asia from 1990 to 2022 exhibited evident time series characteristics. Extremely severe desertification expanded from 1990 to 2009 and subsequently shrunk; (2) The degree of desertification in the arid regions of Asia exhibited different change characteristics in different periods, and the converted area of the same conversion type was different in different periods; (3) Different desertification conversion types in different periods have different drivers; however, overall, soil moisture has the greatest contribution to desertification conversion type. These results provide a scientific reference for the formulation of reasonable desertification prevention and control policies.

Soils are crucial life supporters and nutrient providers, their functionality impacted by their nutritional balance, pH, and organic matter content. These substrates help regulate water, support diverse organisms, and play a critical role in carbon sequestration, especially in the context of climate change. However, soils are under threat from anthropogenic and climatic pressures, warranting active resource management strategies. The European Union (EU) has acknowledged soil sustainability’s importance, encouraging eco-friendly agricultural practices and enhanced soil carbon storage. However, the criticality of soils is often overlooked when establishing global sustainable development goals. Counteracting soil degradation is key in battling desertification and influenced by factors like unsustainable agriculture, deforestation, and poor irrigation. Innovative solutions like circular economy approaches and sustainable biomass utilization are necessary to reduce greenhouse gas emissions. Also, improving dietary habits and reducing food waste can help mitigate the environmental impact of food consumption, with a shift towards plant-based proteins being more sustainable. Addressing these challenges will contribute to a more sustainable and resilient future.

Abstract Background Water availability is the key limiting factor for plant productivity in drylands covering ca. 40% of Earth’s land surface. For such ecosystems to retain productivity and biodiversity under climatic change, it would be valuable to identify/promote keystone plant species that (i) have developed strategies to more efficiently utilize moisture resources not easily accessible and (ii) improve moisture conditions for neighboring plants. The very deep-rooted Ziziphus lotus, considered an ecosystem engineer, is one such example. However, it is not known which biotic traits: (a) canopy interception of moisture/rainfall, (b) hydraulic redistribution of deep ground moisture by roots, or non-biotic factors: (c) soil’s volume, and (d) organic matter content, Z. lotus activates/modulates to play such a role. We, thus, selected dryland ecosystems where the plant dominates and measured for potential effects on the less deep-rooted Thymbra capitata. For assessing impacts on ecosystem productivity, we measured the spatial aggregation of ca. 3600 T. capitata plants. As a proxy for soil moisture availability and its spatial variability, we conducted a 7-year-long study using thymes’ nighttime rehydration. Sampling extended up to 15 m away from Z. lotus. Results The density of T. capitata plants growing up to 5 m around Z. lotus vs. thymes growing 10–15 m away was found significantly increased (2.5–4.5 times), while their stem/leaf moisture was ca. 10% higher at predawn compared to nightfall during the dry season. This suggests that ecosystem productivity is driven by a greater soil moisture availability around Z. lotus permitting more thyme daytime transpiration, in contrast to thymes growing further away. The phenomenon appeared only under dry topsoil (during the dry season; becoming stronger during dry years). Morning dew/rainfall interception from the canopy or soil depth/organic matter did not show significant effects, leaving only the hydraulic lift properties of Z. lotus as the most likely driver for soil moisture availability. Conclusions The deep-rooting properties and hydraulic lift potential of Z. lotus may be the key in permitting it to boost ecosystem productivity. Such hydraulic plant traits require more attention as they may prove valuable in combating desertification and restoring ecosystems in arid/semiarid regions threatened by climate change.

In Ricardo Piglia’s novel Blanco nocturno, Detective Croce tries to solve a murder that raises questions of racial and economic motives, symbolizing the alignment of the extractive economic agents rooted in colonialism. The landscape of the Argentinean pampas embodies the intersection of indigenous genocide and climate disaster. Through the study of the nostalgic connotation of the use of the desert as a landscape, the novel connects the historical perspective of the XIX century narrations of the “Conquista del desierto”—, as writers depicted Argentinian landscapes as an empty “desert” with the objective of colonizing the land and repopulating it, with presentday concerns of desertification. This article will examine a series of metaphorical images, referred to as the “specters of the Anthropocene,” which include an abandoned factory in the middle of the “desert,” the construction of a mall, and a juxtaposition of a diverse array of the electromagnetic spectrum such as electric light, to highlight anxieties surrounding technological progress and environmental destruction. [ABSTRACT FROM AUTHOR]

Grassland degradation (within-state change) and desertification (state conversion from grasslands to deserts) are different states in the complex dynamic process of grassland deterioration. However, the dynamics and associated drivers of the two states have been rarely examined separately, which is critical for early warning and conservation policy making. Here, the grassland degradation and desertification in Central Asia (CA) were studied due to their evident vulnerability to climate extremes and human activities. We performed a two-step approach to identify the critical state zones first (i.e., grasslands, deserts, and the desertification zones) and then assess the vegetation dynamics within each zone. Finally, we quantified the roles of CO2 fertilization effect, climate change, climate variability, land use (LU), and anthropogenic climate change (ACC) on the vegetation dynamics in different state zones. The results showed that the areas of grasslands and sparse vegetation regions (including deserts and desertification zones) were stable from 2000 to 2020, but the trends of vegetation greenness were divergent with a reduction in grasslands and an increase in sparse vegetation regions. Furthermore, climate change and climate variability were the main driving force affecting grassland degradation in CA. Yet the vegetation greening in the desertification and desert zones was mainly driven by the rising CO2 and LU. Moreover, ACC degraded 20.63% of grasslands and sparsely vegetated lands in CA on the baseline of 2000. The results highlighted the risks of grassland degradation in CA. This study proposed a methodology to examine grassland degradation and desertification in detail and quantify the associated driving factors (especially ACC) at the pixel scale, which provided some insights on developing region-precise strategies for grassland conservation in CA and other drylands.

Dryland soil salinization strongly affects soil properties, with severe consequences for regional ecology, agriculture and the aeolian dust dynamics. Given its climate-sensitivity it forms a serious environmental hazard, and to cope with this challenge during current global warming it needs to be better understood. The Bajestan Playa in the strongly salinization-affected Iranian drylands hosts several protected areas and forms an important regional dust source. Hence, soil salinization in this region affects local and regional ecosystems and societies, but was not systematically studied yet. Using an unprecedented comprehensive approach we systematically monitored regional soil salinity 1992–2021 using remote sensing as well as on-site field and laboratory measurements, and linked these with regional and global climatic data to understand (i) the spatio-temporal soil salinity dynamics, (ii) the impact of regional and global climate changes, and (iii) the potential of our approach for further soil salinity studies.Our annual time resolution over three decades provided significantly deeper and unprecedented insights into soil salinization: Both regional annual precipitation and temperature control soil salinity, but the latter responds to precipitation with time lags of up to two years and to higher temperatures without any time lag. This probably reflects the transport time of leached soluble salts from their sources following humid years. No systematic soil salinity changes were observed within the playa basin, but outside the basin soil salinity systematically increased. Whereas regional precipitation did not show a systematic trend during the last decades, regional temperature increased and was mostly correlated with the increasing GLOTI, POL and TSA climatic indices. Hence, given ongoing global warming a further increase of regional soil salinization should be expected, with serious consequences for saline dust emissions, the regional protected areas and climate-related migrations. Altogether, our multi-disciplinary pioneer study demonstrates a high future application potential also for other salinity-affected drylands, forming a base to deal with the consequences of ongoing global climate change.

The ability to determine the spatial distribution of rare fungal species is critical to understanding the environmental factors that affect them. Maximum entropy (MaxEnt) spatial distribution modeling solves this problem by allowing inferences about the distribution of species in a gradient of environmental factors based on occurrence data. To identify patterns of spatial distribution based on objective data, models of the potential geographical distribution of the rare polyporoid fungus of Picipes rhizophilus under current conditions (~1950–2000) and with predicted future climate changes (2100 AD) on a global scale have been created. The species Picipes rhizophilus can develop in steppe habitats of both plains and mountains. Most known habitats of the species are found in the ecoregions that make up the temperate grasslands, savannas and shrublands, Mediterranean forests, woodlands and scrubs, and desert and xeric shrubland biomes. The species is not associated with forest biomes, but it can be found in habitats located on their territory, subject to the processes of climate aridization and desertification. The species Picipes rhizophilus can develop in steppe habitats of both plains and mountains. Modeling the potential distribution of the species under the selected climatic scenario has shown the dynamics of changes in its range. The species-friendly climate area will increase in the North American continent, while there will be no significant changes in Europe and adjacent areas of Africa. In the most favorable territory for the species, located in the basin of the Western Manych River, conditions will become less favorable. There will be a local shift in the areas of potential distribution in the Asian part. [ABSTRACT FROM AUTHOR]

Land degradation is a global natural hazard that can be controlled by distinguishing susceptible areas. Although new approaches for determining areas prone to land degradation are necessary, spatial modeling of this hazard remains a challenge. This study aimed to investigate the efficiency of the weight of evidence (WOE) and evidential belief function (EBF) models for spatial modeling of land degradation in a semi-arid region in Iran. The trend of Net Primary Production (NPP) changes related to 2001-2020, obtained from MOD17A3, was taken into account to specify the inventory of land degradation in the study area. 120 random points were chosen as degraded points in areas with decreasing trend in NPP during 20 years. 70% of the dataset was randomly selected as a training set for the modeling step and 30% of them were selected as the testing set for the validation step. Fifteen geo-environmental factors including temperature, precipitation, slope, aspect, altitude, land use, normalized difference vegetation index, normalized difference salinity index, vegetation soil salinity index, normalized difference moisture index, visible and shortwave infrared drought index, electrical conductivity, and sodium adsorption ratio of groundwater, groundwater table, and annual depletion of groundwater resources were selected as influential factors or independent variables for modeling. The modeling process was done in ArcGIS software after calculating the values of EBF and WOE in excel. And finally, the efficiency of the models was analyzed using the area under the ROC curve. The findings illustrated that EBF with AUC = 0.72 had better performance for spatial modeling of land degradation in the Qazvin plain. Also according to the outputs of both models, north, northeast, northwest, west, southwest, and south of the Qazvin plain were susceptible to LD. The results of this research successfully suggested a new land degradation modeling method that can be used in different areas.

Abstract The forecasted increased frequency and intensity of extreme climatic events may strongly affect ecosystem structure and function in the future. It is unclear how ecosystems will function in the long run over a large spatial scale under a new extreme water cycle. This open question calls for a conceptual framework as a fundamental basis for theoretical and experimental exploration of ecosystem function on a large scale driven by an extreme climate envelope. To assess the problem on a large scale, we investigated hyper‐arid ecosystems (HAEs) as natural tangible models that already function under an extreme climatic envelope. Our new assertion is that if extreme climate change drives arid lands to function under alternate extreme conditions, then arid land ecosystems will function like an HAE as an alternative state, rather than progress to desertification. To support our assertion, we developed a conceptual framework of HAEs that includes a geo‐hydrological “abiotic engine” that drives HAE function by soil moisture diversity and plant functional groups. Based on this conceptual framework, we suggest incorporating two new hypotheses in climate change studies to advance our understanding of responses of large‐scale, water‐limited ecosystems: (1) Hydro‐climatic extremes in water‐limited ecosystems will reduce the degree of resource conservation by slope ecosystems due to reduction in plant cover and soil. The decreased ecosystem function on the slope will be compensated for by increasing the effect of the abiotic engine on the ephemeral stream, thus enhancing meta‐ecosystem functioning in the ephemeral stream. (2) In water‐limited ecosystems, climate change toward hydro‐climatic extremes will rescale the dominant hydro‐ecological processes of pulse–reserve, source–sink, and connectivity along the semiarid, arid, and HA gradients in two ways: (i) shrinking of both spatial and temporal dimensions; and (ii) shrinking in the temporal dimension and expanding in the spatial dimensions. The first rescaling trajectory is related to biodiversity–ecosystem function and the second to the abiotic engine processes.

Land degradation has become a catastrophic global environmental issue. The current status of land degradation and changing trends of land remain unclear on the Qinghai-Tibet Plateau (QTP). This study integrated an Optimal Land Degradation Index (OLDI) and spatial footprints of three land degradation pathways (i.e., salinization, desertification and soil erosion) to investigate changing trends and degradation risks from 2001 to 2021 on the QTP. The results showed that land improvements were the dominant changing trends on the QTP compared to land degradation, accounting for 18.83% of the whole plateau. The regions with land improvements were mainly distributed in the northeastern QTP. High-risk degraded land covered an area of 0.55 million km2, and low-risk degraded land covered 0.78 million km2. The spatial distribution of high-risk degraded land varied gradually from scattered small areas to increasingly frequent connected patches from southeast to northwest. Potential driving factor analysis illustrated that land degradation resulted from multidimensional driving forcings, including topography, climatic factors, and human activities. The findings in this study can provide great insight for alpine ecosystem development and make adaption to achieve carbon neutrality with global warming.

Earth’s dryland (hyper-arid, arid, semi-arid, and dry sub-humid) ecosystems face increasing aridity and invasion by exotic plant species. In concert, these global changes threaten the biodiversity, ecosystem functioning, and economic viability of drylands worldwide, with critical implications for environmental quality and human wellbeing. Positive interactions (facilitation) from shrubs can buffer native plant communities against increasing aridity, but this could backfire if exotic species are facilitated more than natives. Thus, understanding how native and exotic plant species respond to shrub facilitation along aridity gradients is essential for predicting the ecological consequences of concomitant aridification and exotic plant invasion in changing drylands. Here, we performed meta-analyses using 152 independent studies to compare the positive effects of shrubs on native vs. exotic plant species across Earth’s dryland ecosystems that vary in aridity. Globally, shrubs facilitate the abundance, diversity, reproduction, and survival of native plant species but do not consistently facilitate any measure of exotic plant performance. As aridity increases, shrub effects on native species do not change, but shrub effects on exotic species become more negative. Thus, across dryland ecosystems globally, shrubs facilitate more measures of native plant performance than exotic plant performance, and as aridity increases, shrub facilitation remains stable for native species but transitions towards resistance for exotic species. At the global scale, dryland aridification may pose a greater threat to exotic species than native species, inasmuch as shrubs and their interactions remain intact.

This paper presents a literature review of black locust (Robinia pseudoacacia L.) and the knowledge accumulated by Romanian foresters and researchers, covering species propagation, stand management, and vulnerability issues. As highlighted by numerous authors, black locust manifests dual features, both as an exogenous species and one that is already naturalized. The main drivers for this species' expansion in Romania is its ecological adaptability on degraded lands, fast growth, and high biomass yields, in addition to other economic benefits. Black locust plantations and coppices also offer an important range of ecosystem services such as CO2 sequestration, landscape reclamation, fuel wood, or maintaining traditional crafts in regions with little to no forest cover. Highlighted disadvantages include short lifespan, invasiveness when introduced on fertile sites, and dieback in drought/frost prone areas. The results of extensive research and studies are captured in technical norms, although aspects such as species genetics, invasive potential, and adaptation to climate change dynamics call for more research and optimizing in species management. As Romania rallies its efforts with those of the international community in order to address climate change and desertification, black locust stands out as a proven solution for reclaiming degraded lands when native species are not an alternative. [ABSTRACT FROM AUTHOR]

At the modern stage of society's development, ecology is seen as a complex, interdisciplinary science of the relationships of organisms, society and the environment. Ecology is a science that studies the regularities of the life of organisms in their natural living environment and taking into account the changes made in this environment as a result of human activity. In recent years, the mass media has been constantly talking and writing about ecology, environmental problems related to anthropogenic activity. The person with his activity is heavily polluted and continues to negatively affect the environment at increasing rates. This reckless behavior of humans and the whole of society threatens planet Earth with imminent doom, no less than the use of nuclear weapons. Only from the positions of modern science ecology is it possible to develop issues related to the prudent use of the natural resources of the biosphere and the fight against changes brought about in nature by human activity in the age of the scientific and technical revolution. For this reason, it is necessary to seek information and a solution to the key current problems: What are the main pollutants of the atmosphere, hydrosphere and lithosphere? What is the origin of these substances? How does their impact affect life on Earth? What approaches and methods are needed to prevent environmental pollution? [ABSTRACT FROM AUTHOR]

Land degradation adversely affects the well-being of approximately 3.2 billion people worldwide and results in a loss of about 10% of annual gross domestic product. Degradation dynamics are often creeping and non-linear, hence the adverse consequences are often not immediately perceived. In consequence, methods for assessing future risks of land degradation and risk reduction strategies are trailing far behind those that have been developed within disaster risk research for natural hazards that appear as shocks, such as floods or earthquakes. Therefore, the objective of this paper is to analyze existing land degradation risk assessment approaches to assess what is hindering a link to land management strategies. The synthesis presented here reveals that while approaches to calculate land degradation risk have evolved to capture ever more processes and factors involved in land degradation, no consistent conceptual framework for land degradation risk has been developed to the present day. Key identified short-comings are that risk terminology is not consistent across and within studies and that there is often no distinction between a degradation status assessment and an assessment of future risk. Damage is rarely explicitly considered or quantified, and in the majority of studies there is no clear distinction between processes and drivers, hazard and vulnerability. Finally, novel conceptual ideas integrating the risk framework developed within disaster risk research are proposed to stimulate debate and facilitate the development of effective risk reduction measures for land degradation.

Abstract Grassland‐to‐shrubland state change has been widespread in arid lands globally. Long‐term records at the Jornada Basin USDA‐LTER site in the North American Chihuahuan Desert document the time series of transition from grassland dominance in the 1850s to shrubland dominance in the 1990s. This broadscale change ostensibly resulted from livestock overgrazing in conjunction with periodic drought and represents the classic “grassland‐to‐shrubland” regime shift. However, finer‐scale observations reveal a more nuanced view of this state change that includes transitions from dominance by one shrub functional type to another (e.g., based on leaf habit [evergreen vs. deciduous], N2 fixation potential, and drought tolerance). We analyzed the Jornada Basin historic vegetation data using a fine‐scale grid and classified the dominant vegetation in the resulting 890 cells on each of four dates (1858, 1915, 1928, and 1998). This analysis allowed us to quantify on contrasting soil geomorphic units the rate and spatial distribution of: (1) state change from grasslands to shrublands across the Jornada Basin, (2) transitions between shrub functional groups, and (3) transitions from shrub‐to‐grass dominance. Results from our spatially explicit, decadal timescale perspective show that: (1) shrubland ecosystems developing on former grasslands were spatially and temporally more dynamic than has been generally presumed, (2) in some locations, shrublands initially developing on grasslands subsequently transitioned to ecosystems dominated by a different shrub functional type, with these changes in shrub composition likely involving changes in soil properties, and (3) some shrub‐dominated locations have reverted to grass dominance. Accordingly, traditional, broad characterizations of “grassland‐to‐shrubland” state change may be too simplistic. An accounting of these complexities and transitions from one shrub functional group to another is important for projecting state change consequences for ecosystem processes. Understanding the mechanisms, drivers, and influence of interactions between patterns and processes on transitions between shrub states defined by woody plant functional types will be germane to predicting future landscape change.

Identifying priority areas and allocating suitable measures to control desertification can improve the efficiency and precision of land restoration when funds are limited. However, few studies have attempted to link priority areas and land restoration options to support desertification control at the national level. In this study, a framework was designed to identify priority areas for desertification control by integrating land sensitivity and cost and benefit indicators and then allocate eight land restoration options based on land use type and water resources capacity. The framework was validated in northern China and successfully linked priority areas and land restoration options to support desertification control. In northern China, regions with high priority for desertification control accounted for only 11.5% of the total area and were scattered in central and northwestern areas. Of those high priority areas, 51.2% should be protected without further disturbance, which were primarily distributed in the western part of northern China. Other regions could be moderately developed within the water resources capacity, including development of the ecological industry. In addition, comprehensive policies or projects, including desert national parks, land ownership confirmation, and green finance policy, should be initiated to augment the effects of desertification control and support regional economic development.

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This study shows the impact of the reforestation program by some tree species (Pinus halepensis, Cupressus sempervirens and Eucalyptus camaldulensis) on the soil physicochemical parameters in south-western Algeria steppe. The study was realized on soil samples from the Touadjeur site. One hundred soil samples were taken from the field, followed by physicochemical analyses in the laboratory. A comparison of the soil elements between reforested and unreforested sites considered as a control was carried out. The results show that there are differences in the physicochemical parameters of the soil between the reforestation and the non-reforestation ones constituted by a steppe vegetation. The ANOVA one way test shows a highly significant difference change in soil physical parameters, moisture, holding capacity and saturated hydraulic conductivity, but no change in apparent density, actual density and color. Also, from a chemical point of view, the differences concern the organic matter, organic carbon, pH and certain soil contents. The main differences in soil properties between the reforestation sites and the control site, reflect the consequences of forest management adopted by the forest services, most probably the choice of reforestation species.

The United Nations’ convention on desertification encourages the participating countries to introduce criteria for developing Early-Warning Systems (EWS) in order to monitor and assess desertification. The objective of the present study was to establish an EWS for desertification assessment in Kashan plain, Iran, using the methodology of practical and general applicability. Designing EWS requires a model to identify the influential criteria and areas vulnerable to desertification. The Kashan Plain’s EWS relies on the Iranian Model for Desertification Potential Assessment (IMDPA) to establish desertification thresholds and generate desertification maps with Geographic Information Systems (GIS). The EWS of Kashan plain was designed to calculate hydrologic (groundwater level and electric conductivity of groundwater indices) and climatic (precipitation, Transeau aridity, and drought indices) criteria and assess the degree of regional desertification. Afterwards, the desertification intensity maps of criteria and indices were produced and overlapped. The EWS was developed in areas most bound to be threatened by desertification. EWS quantifies desertification data and thresholds to issue desertification assessments and warnings for management purposes. In the next step, Client–Server program was designed based on an algorithm defined by Java programming language and implemented as a data collection, analysis, and response management system. Whenever the thresholds exceed the defined limits, warning messages can be sent via SMS or internet to relevant system managers for appropriate action.

The United Nations Sustainable Development Goal 15 (Life on Land), adopted the indicator 15.3.1 to measure the Land Degradation Neutrality. This indicator is based on three sub-indicators: (1) Trends in Land Cover, (2) Land Productivity and (3) Carbon Stocks. The Land Productivity sub-indicator refers to the total above-ground Net Primary Production and reflects changes in health and productive capacity of the land. It can be calculated using the Land Productivity Dynamics approach, which performs a combined assessment of the long term tendency of change of land productivity and its current level relative to homogeneous land areas.Here, we present the R-based tool LPDynR, which implements the Land Productivity Dynamics approach for the calculation of the Land Productivity sub-indicator. LPDynR ingests vegetation-related indices derived from time series of remote sensed imagery. The final indicator is a 5-class map, ranging from declining to increasing land productivity. As an example of LPDynR functionalities and applicability, we present a case study for Europe. First, we show the general way to calculate the indicator for the entire time series (2000–2019), explained in a step by step process. Secondly, we show how to alternatively calculate the indicator based only on the long term tendency of change, but we evidence the added value of including the current level of productivity to refine the final indicator. Finally, we present some code for the calculation of “partial indicators” in terms of time scale along the observation period, which may help the user to understand the land productivity dynamics within the time series, as well as to assess the stability of the final product. While the indicator shows a general positive dynamics across Europe during the period 2000–2019, some of the partial maps show more negative trends, demonstrating the highly fluctuating character of vegetation.

Desertification threatens land integrity, hinders the improvement of livelihoods, restricts global economic development, and affects social stability. The countries and regions involved in the Belt and Road Initiative have long suffered from varying degrees of desertification, land degradation and drought, and experience the most severe desertification of anywhere on the planet. Existing research on desertification has mainly focused on technical aspects of this problem and on sand control and management. Most studies have covered topics such as dryland, forestry, agriculture, animal husbandry, and water and soil conservation. However, few studies have been conducted from the perspective of public policy. In particular, policies and regulations for the prevention and control of desertification in countries participating in the Belt and Road Initiative remain poorly understood and undervalued. This study therefore examined policies and regulations for preventing and controlling desertification in representative Belt and Road countries. The developmental context, formulation of measures to safeguard the environment, modes and effects of their implementation, and the overall management systems in these countries were analyzed, and their similarities, differences, and correlations were explored in depth. The findings of the study will provide inputs for promoting cooperation among industries, enterprises, and institutions in typical desertified countries, whose collaborative efforts will contribute to promoting green development within the Belt and Road Initiative. Moreover, they will provide a reference for researchers, policy makers, and environmental regulators to shape the next generation of desertification control policies and regulations and to support environmentally sustainable implementation of the Belt and Road Initiative.

The Qaidam Basin is a cornucopia of salt mineral resources in China, but desertification in the basin has seriously impacted residents’ lives and economic development. Comprehensive analyses of the spatial distribution characteristics of desertification and its driving factors will improve understanding of the causes of desertification. To explore these causes and related driving factors, we used the geographical detector model and geographical information system (GIS) techniques to quantify the relative importance and interactions of driving factors, including meteorological, environmental, and human factors. We found that desertification in the southern Kunlun Mountains, eastern Qilian Mountains, and front of the alluvial fan in the northern Kunlun Mountains was low. This was mainly due to the relatively abundant water resources in these areas. Desertification in the central and western Qaidam Basin was high primarily on account of the abnormally high evaporation. The power of determinant value showed that evaporation (0.481) had the strongest impact on desertification, followed by precipitation (0.460), vegetation type (0.360), soil type (0.293), and temperature (0.251). Evaporation has significantly positive effect on the level of desertification, and precipitation has significantly negative effect. Meteorological factors had the greatest impact on desertification, followed by environmental factors, whereas human factors were the least influential. Despite the small population in the basin and limited economic development, the impact of human activities on desertification cannot be ignored. Our results further indicated that the interactions between the driving factors could enhance the evaluation of desertification. This study comprehensively considered three types of impact factor and a total of nine driving factors. It also analyzed the spatial distribution characteristics and driving factors of desertification in the basin, which improved understanding of desertification in such arid and semi-arid regions in northwest China.

Global climate change and extensive socio-economic development both act to decrease the ground cover in the semi-arid sandy grasslands of Horqin district, northern China. Loss of ground cover increases the direct exposure of the surface soil to erosion by strong winds—a process that ultimately converts grassland into sandy desert. Three ways to restore such degraded lands through afforestation were evaluated in terms of total carbon stored in the restored ecosystems compared to that in the control. Total carbon comprised that stored in the biomass of trees, herbs, standing litter, and soil (to a depth of 100 cm). The three restoration treatments were (1) enclosing the grassland within a shelter belt of Populus × beijingensis (FG), (2) afforesting small but well-distributed patches within the grassland using Pinus sylvestris var. mongolica (MG), and (3) afforesting small but well-distributed patches within the grassland using Ulmus pumila (UG). A plot of desertified sandy grassland in which the dominant species were Agriophyllum squarrosum (Linn.) Moq. and Cenchrus echinatus Linn. was used as the control (CK). The results show that total ecosystem carbon storage in FG, UG, and MG increased significantly over time in comparison with that in CK. After more than 20 years, all three grassland restoration approaches are expected to contribute greatly to global ecosystem carbon sequestration. The rank order of total ecosystem carbon storage content is: FG (104.29 t/ha) > MG (102.96 t/ha) > UG (92.24 t/ha) > CK (24.48 t/ha). Soil carbon storage in the 0–30 cm and 0–50 cm depth ranges accounted for 41.81–60.13% and 59.42–80.80% of the total soil pool, respectively, across all treatments. FG had the highest biomass carbon storage, which was linked to differences in tree species. The structure of the plant community created in these treatments was different from that found in natural stands of forest and in grasslands without trees or shrubs. All the three treatments are suitable for the restoration of moderately desertified sandy grasslands in south-eastern Horqin, northern China, depending on the availability of water and soil nutrients. The results of the present study highlight the importance of degraded grassland restoration programs in enhancing ecosystem carbon storage.

Degradation characterized by depleted vegetation cover is a serious environmental problem in African rangelands. It poses a serious threat to millions of pastoralists and agropastoralists who depend on livestock as a source of livelihood. Consequently, there has been a growing global interest to consolidate efforts to restore degraded ecosystems. For example, the UN decade of Ecosystem Restoration initiative aims at uniting the world behind a common goal of preventing, halting and reversing the degradation of ecosystems. Grass reseeding using native perennial species has been identified as one of the practical ecological strategies for restoring degraded African rangelands, enhancing vegetation cover and forage production. Knowledge of the multifaceted performance of African rangeland grasses in terms of morphoecological traits, interaction with weeds and water use efficiencies is however largely limited and often elusive. Perennial grasses indigenous to African rangelands Cenchrus ciliaris L. (African foxtail grass), Enteropogon macrostachyus (Hochst. Ex A. Rich.) Monro ex Benth. (Bush rye grass) and Eragrostis superba Peyr. (Maasai love grass), were established in an African semi-arid rangeland under natural conditions to fill this knowledge gap. Morphoecological plant traits: aboveground biomass (shoot, leaf and stem) production, plant densities, basal cover, tiller densities and plant height were measured 9 months after establishment. Interaction between the target grass species and weeds and water use efficiencies (WUE) were also determined. Enteropogon macrostachyus displayed significantly higher values for plant densities, tiller densities and basal cover, indices commonly used to estimate the potential of grasses for ecological restoration. Eragrostis superba produced the highest shoot biomass and water use efficiencies. This is attributed to its higher leafy biomass fraction. Higher aboveground biomass production of E. superba demonstrate its suitability for enhancing rangeland productivity. Cenchrus ciliaris suppressed the weeds. This is linked to its aggressive and allelopathic nature. In conclusion, the three perennial grasses displayed distinct morphoecological traits. In order to achieve successful seed-based restoration of degraded African rangelands using native perennial grasses, careful selection species to maximize on their unique traits is recommended. Ultimately, this selection process should match the desired restoration outcomes and subsequent use of the rangeland.

Increased aridity and human population have reduced tree cover in parts of the African Sahel and degraded resources for local people. Yet, tree cover trends and the relative importance of climate and population remain unresolved. From field measurements, aerial photos, and Ikonos satellite images, we detected significant 1954–2002 tree density declines in the western Sahel of 18 ± 14% (P = 0.014, n = 204) and 17 ± 13% (P = 0.0009, n = 187). From field observations, we detected a significant 1960–2000 species richness decline of 21 ± 11% (P = 0.0028, n = 14) across the Sahel and a southward shift of the Sahel, Sudan, and Guinea zones. Multivariate analyses of climate, soil, and population showed that temperature most significantly (P

Semi‐arid and arid landscapes (dry‐lands) cover 41% of the Earth's land surface over five continents. These areas are home to 55% of mammal species. Bats have the second highest species richness among mammals, and, although many species are adapted to arid conditions, they are particularly sensitive in these habitats and require conservation priority.Information on bats in arid and semi‐arid landscapes is scattered, patchy and focused on small‐scale studies; therefore, we undertook a systematic review using the PRISMA protocol to identify the current knowledge status, detect knowledge gaps and propose future research priorities.We analysed 346 published articles and evaluated 40 topics within five topic categories (taxa studied, methodologies used, biology, ecology and conservation). The most commonly studied topic categories were ecology and biology. However, we found a gap in the topic category conservation (including topics such as conservation status and roost conservation). Our network analysis of topics within the categories showed that most ecology papers were focused on distribution, species richness and habitat use.When we analysed keywords, we found that phylogeny, taxonomy and distribution demonstrated relatively high presence. Moreover, comparison of the percentage of studies conducted in dry‐lands and the percentage of land surface area covered by dry‐lands in the continents revealed that dry‐lands in Africa and Australia were especially under‐represented. Our review shows that knowledge of bats in semi‐arid and arid landscapes is biased towards new records of the distribution of species, as well as covering systematic/taxonomic and morphological aspects of bat biology.We suggest that research on conservation measures and guidelines to protect the bat species found in semi‐arid and arid landscapes should be prioritised, together with the sharing of knowledge with local practitioners and the development of citizen science programmes. [ABSTRACT FROM AUTHOR]

An assessment of the vegetation in the arid desert habitats of Kuwait was carried out in 2008 and 2009. The richness of vegetation was examined in relation to human activity (e.g., grazing, recreational camping) and impact factors in two open areas (north of SAANR, NS; south of Kabd, SK) were compared with two protected areas (SAANR, Kabd). In total, 420 quadrats were sampled along 84 transects at random locations along off-road vehicle tracks in the study area. The data were classified using two-way indicator species analysis (TWINSPAN) to divide samples into three groups of high internal similarity in terms of plant species presence. Total plant species richness was 20, 35, 2 and 17 species per area in SAANR, Kabd, NS and SK, respectively. Compared to protected areas, open grazed land had markedly fewer species and reduced vegetation cover in the form of grasses, forbs and shrubs. Habitat conditions were especially impoverished in NS, with 99% of samples supporting only one plant species. The low plant diversity in the unprotected open rangelands demonstrates the need for a new strategy to rehabilitate ecological habitats.

Alpine sand dunes restoration is extremely difficult but important in the ecosystem restoration. Sand dunes are known as harsh soil and poor seed bank which freed from advantages on plants growth naturally. Effective restoration measures are required to guide the sand dune restoration. Here, indigenous grass (Elymus nutans) was sown in sand dune on the Zoige Plateau and treated with no sand barrier (CK) and environmental friendly materials including wicker sand barrier (wicker) and sandbag sand barrier (sandbag). The soil conditions were assessed by measuring the soil moisture and nutrients of the topsoil, and interspecific relationship and population niche were utilized to analyze the plant community structure variances among different restoration measures. Results showed that the soil and vegetation in the sand barriers measures were better than that in the CK. The soil moisture in the sandbag measure was 16.67% higher than that in the wicker measure. The nutrients content and microbial biomass were also the best in the sandbag measures. The ratio of strong association was the highest in the sandbag measure and the lowest in the CK, whereas the plants had the highest none association ratio in the CK. In addition, the average population niche overlap ranked by sandbag (0.39)>wicker (0.32)>CK (0.26). Thus, incorporation of sand barriers and indigenous grass seeding in alpine sand dunes could promote the sand dune restoration. And the sandbag measure showed a stronger improvement effect on the sand dune soil and vegetation conditions than the wicker measure. [ABSTRACT FROM AUTHOR]

The Caatinga is an ecologically unique semi-arid region of northeast Brazil characterized by high levels of endemism and severe anthropogenic threats from agricultural development and climate change. It is also one of the least known biomes in Brazil due to a combination of inadequate investment, low regional research capacity and difficult working conditions. However, while the lack of scientific knowledge of the Caatinga is well known, the spatial and temporal distribution of knowledge production has not been investigated. This is important because such biases undermine the development of effective conservation policy and practice and increase the uncertainty associated with conservation actions. Here, we map the geography of conservation knowledge production in the Caatinga and use an innovative hurdle model to identify the presumptive factors driving these patterns. Our analysis revealed strong geographic patterns, with research sites concentrated in the east of the region and in areas close to roads and research centres. There was also a positive association between conservation knowledge production and risk of desertification, indicating that conservation scientists are responding to conservation challenges faced by Caatinga’s fauna and flora arising from climate change. Our results also highlight the pivotal role of pioneer scientists (those who develop research sites in previously unstudied/understudied areas) in determining the future geographic patterns of knowledge production. We conclude our article with a brief discussion of potential policies for increasing the spatial representativeness of conservation research in this remarkable ecosystem. [ABSTRACT FROM AUTHOR]