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The complex topography in mountainous regions, exemplified by factors like slope aspect, leads to noticeable variations in vegetation patterns, which are fundamental for understanding mountain ecosystems. However, a consistent global-scale quantification of topography's influence on vegetation patterns is still lacking. Here, we utilize two phenological metrics as proxies for vegetation-maximum vegetation greenness and seasonal greenness amplitude-computed from Sentinel-2 images, to quantify differences across three topographic factors: slope aspect, steepness, and elevation within each 0.15°×0.15° mountain grid. Our mapping reveals clear geographic patterns indicating that topography strongly influences vegetation in arid and polar ecosystems, with an influence approximately 1.9 times higher than in temperate ecosystems. Topography is also important in humid regions, as demonstrated by diverse vegetation types growing on different slope aspects, steepness levels, and elevations. Additionally, the impacts of slope aspect, steepness, and elevation vary within the same region. In 25.9% of mountain grids, slope aspect causes the largest difference in vegetation patterns, while elevation and steepness account for 43.1% and 31%, respectively. Our study highlights the hotspot areas where topographic effects on vegetation patterns are most pronounced, enabling researchers to focus on these regions for better parameterization of Earth system models.

[Objective] To investigate the spatial distribution and cooperative utilization characteristics of soil water under the orchard-farmland mosaic pattern in the southern Loess Tableland. [Methods] The 10-year-old, 21-year-old, and 25-year-old apple orchards (AO10, AO21, and AO25) and their adjacent farmland were selected in Changwu tableland were selected to quantitatively calculate the contribution of soil water storage to water consumption of orchard. By measuring the soil water content at relevant sites in the orchard-farmland interface zone after the rainy season in 2021. [Results] The precipitation in 2021 is 756 mm, which was a typical wet year. The rainfall infiltration depth of farmland and AO21, AO25 orchards reached 8.4, 7.0, and 5.0 m at the end of November, respectively. AO10 orchard-farmland boundary zone is 4 m deep, the soil water content in the lower part is larger than that in the upper part, and the average soil water content was 25.5% in the 4—10 m soil layer. In AO21 orchard, the average soil water content of the 0—7 m soil layer was 22.1%, and that of the 7—10 m soil layer was 15.0%. the average soil water content of the 0—5 m soil layer of AO25 orchard was 20.9%, and that of 5—10 m was 13.6%. The soil dry layer of AO21 and AO25 orchard was below 7.0 and 5.0 m, respectively. In the horizontal direction, the distance of soil water used by AO21 and AO25 orchards from adjacent farmland reached 5 and 8 m, respectively, and the water supply from fields to orchards at the agro-fruit interface was 0.08 and 0.25 m3/m2 when the soil profile was divided by the upper boundary of the dry layer. Below is the actual water supply, which is 0.45 and 0.81 m3/m2, respectively. [Conclusion] The mosaic layout of apple orchards and farmland in the Loess tableland region is a reasonable utilization structure, and factors such as the age of apple trees and the width of adjacent farmland should be considered in land planning and management. The research results will contribute to promote the sustainable utilization and spatial optimization of regional soil water resources.

The vegetation system in arid and semi-arid regions is facing severe challenges, so it is urgent to forecast the evolution of vegetation system. Vegetation pattern dynamics can be used to qualitatively analyze and quantitatively describe the formation mechanism and distribution law of vegetation based on dynamic equations and statistical data. Therefore, this paper selects Baotou region, Inner Mongolia which is a typical semi-arid region and applies vegetation-climate dynamics model to study the effect of climate change on vegetation distribution. The last 60 years of carbon dioxide concentration [CO 2 ], rainfall and temperature data in this region are collected and the correlation between these climatic factors and vegetation density is analyzed. Besides, vegetation growth over the next 100 years is predicted under different climate scenarios. The results reveal that precipitation makes a critical difference in the growth of vegetation, and the vegetation pattern is the result of the synergistic effect of temperature, precipitation and [CO 2 ]. The rate of vegetation desertification is the fastest under current scenario and SSP1-2.6 is the most ideal climate scenario for vegetation growth. Furthermore, we use the optimal control theory to provide a theoretical guidance for the prevention of desertification. [ABSTRACT FROM AUTHOR]

In order to stop and reverse land degradation and curb the loss of biodiversity, the United Nations 2030 Agenda for Sustainable Development proposes to combat desertification. In this paper, a fractional vegetation–water model in an arid flat environment is studied. The pattern behavior of the fractional model is much more complex than that of the integer order. We study the stability and Turing instability of the system, as well as the Hopf bifurcation of fractional order α , and obtain the Turing region in the parameter space. According to the amplitude equation, different types of stationary mode discoveries can be obtained, including point patterns and strip patterns. Finally, the results of the numerical simulation and theoretical analysis are consistent. We find some novel fractal patterns of the fractional vegetation–water model in an arid flat environment. When the diffusion coefficient, d, changes and other parameters remain unchanged, the pattern structure changes from stripes to spots. When the fractional order parameter, β , changes, and other parameters remain unchanged, the pattern structure becomes more stable and is not easy to destroy. The research results can provide new ideas for the prevention and control of desertification vegetation patterns. [ABSTRACT FROM AUTHOR]

The Klausmeier–Gray–Scott model of vegetation dynamics consists of a system of two partial differential equations relating plant growth and soil water. It is capable of reproducing the characteristic spatial patterns of vegetation found in plant ecosystems under water limitations. Recently, a discrete delay was incorporated into this model to account for the lag between water infiltration into the soil and the following water uptake by plants. In this work, we consider a more ecologically realistic distributed delay to relate plant growth and soil water availability and analyse the effects of different delay types on the dynamics of both mean-field and spatial Klausmeier–Gray–Scott models. We consider distributed delays based on Gamma kernels and use the so-called linear chain trick to analyse the stability of the uniformly vegetated equilibrium. It is shown that the presence of delays can lead to the loss of stability in the constant equilibrium and to a reduction of the parameter region where steady-state vegetation patterns can arise through symmetry-breaking by diffusion-driven instability. However, these effects depend on the type of delay, and they are absent for distributed delays with weak kernels when vegetation mortality is low. [ABSTRACT FROM AUTHOR]

Altay Prefecture, a typical arid region in northwestern China, has experienced the climate transition from warming-drying to warming-wetting since 1980s and has attracted widespread attention. Nonetheless, it is still unclear how climate change has influenced the distribution of vegetation in this region. In this paper, a reaction–diffusion model of the climate–vegetation system is proposed to study the impact of climate change (precipitation, temperature and carbon dioxide concentration) on vegetation patterns in Altay Prefecture. Our results indicate that the tendency of vegetation growth in Altay Prefecture improved gradually from 1985 to 2010. Under the current climate conditions, the increase of precipitation results in the change of vegetation pattern structures, and eventually vegetation coverage tends to be uniform. Moreover, we found that there exists an optimal temperature where the spot vegetation pattern structure remains stable. Furthermore, the increase in carbon dioxide concentration induces vegetation pattern transition. Based on four climate change scenarios of the Coupled Model Intercomparison Project Phase 6 (CMIP6), we used the power law range (PLR) to predict the optimal scenario for the sustainable development of the vegetation ecosystem in Altay Prefecture. [ABSTRACT FROM AUTHOR]

The global climate has undergone great changes in recent decades, which has a significant impact on the vegetation system, especially in arid and semi-arid areas. Based on a dynamic model, this paper studied the response of vegetation pattern to climate change in Qinghai Lake, a typical semi-arid region. The conditions for Turing instability of the equilibrium were obtained by mathematical analysis. The numerical experiments showed the influence of different climitic factors (carbon dioxide concentrations [$ CO_2 $], temperature and precipitation) on vegetation pattern. The results showed that the robustness of the vegetation system was enhanced as precipitation or [$ CO_2 $] increased. Furthermore, we presented evolution of vegetation system under different climate scenarios to forecast the future growth of vegetation. We compared the various climate scenarios with representative concentration pathways (RCP2.6, RCP4.5, RCP8.5). The results revealed that RCP2.6 scenario was a desired climate scenario for Qinghai Lake. Our study also highlighted the measures to avoid desertification by the method of optimal control. We expect that this study will provide theoretical basis for vegetation protection.

Soil aggregates are important for improving the soil quality and structure. Soil erosion causes the fragmentation and migration of soil aggregates. Vegetation restoration is an effective method for controlling soil erosion, and the vegetation distribution on the slope changes the hydrological processes. However, there is a dearth of studies investigating the regulation of vegetation patterns in relation to soil aggregate loss. This study employed a physical model of a slope gully system to examine the characteristics of soil aggregates loss during erosion processes under four distinct vegetation patterns: no vegetation (pattern A), up‐slope vegetation (pattern B), middle‐slope vegetation (pattern C), and down‐slope vegetation (pattern D), utilizing simulated rainfall experiments. The results showed that under various patterns of vegetation, the loss of soil aggregates is predominantly driven by microaggregates (<0.25 mm), A (65.2%) < B (72.4%) < C (77.7%) < D (87.7%). On the contrary, there is an opposite trend of change observed in macroaggregates(>0.25 mm). The vegetation pattern had different effects on the enrichment rate of aggregates in sediments: the enrichment ratio of macroaggregates decreased by 20.9%–64.7% and the enrichment ratio of microaggregates increased by 11.1%–34.5%. The cumulative loss of soil aggregates and the cumulative runoff volume can be described by a linear equation: y = ax + b, where 'a' denotes the rate of soil aggregate loss. Vegetation patterns had the capacity to decrease the rate of macroaggregate loss. Among these patterns, pattern D exhibits the lowest rate, followed by patterns C, B, and A. These results indicated that down‐slope vegetation pattern is effective in reducing the loss of soil aggregates especially macroaggregates. [ABSTRACT FROM AUTHOR]

There is a global stabilization of coastal dunes, during which, the trajectory of vegetation expansion was rarely studied and, thus, still remains unclear. In this study, patterns and driving factors of vegetation expansion during dune stabilization were examined in three coastal dunefields in Victoria, Australia. Results show that the trajectory of vegetation expansion is fundamentally determined by dunefield topography. At the dunefield scale, vegetation colonization can take place at different parts in dunefield, including (1) the landward margins, where the ecosystem is frequently dominated by woody species and the soil is more mature with higher nutrients and water content; (2) the interdune depressions, where is usually dominated by lower elevations and shelters; and (3) the seaward deflation basins and plains, where vegetation shows a more discontinuous and patchy distribution. At the individual dune scale, vegetation usually expands vertically from the dune toe towards the upper dune slope at both the lee side and stoss face of dunes/dune ridges. The deflation basins are more likely to be free of vegetation establishment. Pre‐existing vegetation also plays a critical role in dune re‐vegetation, and subsequent vegetation expansion takes place around the vegetation patches, more usually towards the downwind direction, probably because it can provide seeds for subsequent vegetation spread. Once established, it can also change the micro‐climates by providing shelter, increasing the surface roughness and changing the wind regimes. More importantly, existing vegetation can form a 'fertility island' with higher nutrients, organic matter and water‐holding capacity. Conceptual models depicting the trajectory of vegetation expansion were also generalized. This research provides an original perspective and innovative insight into the patterns and driving factors of vegetation expansion during dune stabilization, under the background of global coastal 'greening', which could be helpful to identify opportunities for management interventions. [ABSTRACT FROM AUTHOR]

[Objective] The spatial distribution characteristics of surface soil particles under different vegetation patterns at Pisha sandstone area in tipical area in Ordos City, Inner Mongolia Autonoous Region, and the sorting and transportation mechanisms of water erosion for soil particles were studied in order to provide a theoretical basis for the restoration of the ecological environment in this area. [Methods] The study was conducted with in-situ monitoring of field runoff plots. The effects of different vegetation patterns on the spatial distribution of surface soil particles on Pisha sandstone slopes under natural rainfall conditions were determined by combining three-dimensional laser scanning and geostatistics. [Results] ① The uniformly distributed vegetation pattern effectively inhibited runoff and sediment production on the slope. The erosion area, average runoff, and average sediment volume were 5.35%, 63.16%, and 76.47%, respectively, lower than observed for the bare slope. ② Under the uniformly distributed vegetation pattern, the contents of soil clay and silt particles were 1.3% and 2.2%, respectively, greater after rain than before rain, and sand content was 3.2% lower. The content of sand particles increased after rain by 5.8% and 15.3% in the randomly distributed and aggregated vegetation patterns respectively, resulting in a coarsening of soil texture. ③ Different vegetation patterns were the main factors causing the spatial variation of soil particles. The uniformly distributed and randomly distributed vegetation patterns increased the nugget coefficients of silt and sand particles after rainfall, and decreased the spatial autocorrelation. The aggregated vegetation pattern decreased the nugget coefficients of clay and silt particles from 95.06% and 83.89% to 0.07% and 0.06%, showing a strong spatial autocorrelation. [Conclusion] A uniformly distributed vegetation pattern produced suitable soil and water conservation benefits on an arsenic sandstone slope, significantly reducing runoff and sediment production and inhibiting soil coarsening.

Interpreting biodiversity patterns and the underlying processes is crucial for evaluating the mechanisms of community assembly, but the view of multifaceted diversity patterns spanning broad spatial extents is less strengthened. We implemented an inventory of 1260 vegetation plots from shrublands across China with standardized methods and analyzed patterns of taxonomic and phylogenetic diversity with differential weighting of common and rare species, as well as phylogenetic co-occurrence structures. Taxonomic and phylogenetic diversity were linearly correlated when common and rare species were weighted equally, but had a logarithmic correlation when species were weighted with their relative abundances. While most shrubland communities were phylogenetically unstructured, the correlation between taxonomic and phylogenetic diversity covaried with phylogenetic relatedness when incorporating relative abundance, but only weakly so in phylogenetically over-dispersed communities. When we correlated patterns of taxonomic and phylogenetic diversity with different weightings for common versus rare species, we found an important role for geographic (e.g., longitude, altitude), climatic (temperature, precipitation) and soil factors. The importance of underlying variables varied between facets of diversity. We found a strong role for altitude in taxonomic, but less so for phylogenetic diversity. Furthermore, the importance of several environmental drivers varied depending on whether diversity metrics were strongly influenced by rare species or put more weight on common and/or dominant species. Overall, our assessment highlights the importance of synthetic analyses of patterns and processes of different facets of biodiversity to capture the full complexity of diversity in conservation studies.

Vegetation in natural desert hinterland oases is an important component of terrestrial ecosystems. Determining how desert vegetation responds to natural variability is critical for a better understanding of desertification processes and their future development. The aim of this study is to characterize the spatial distribution of vegetation in the natural desert hinterland and to reveal how different environmental factors affect vegetation changes. Taking a Taklamakan Desert hinterland oasis as our research object, we analyzed the effects of different environmental factors on desert vegetation using a time-series normalized difference vegetation index (NDVI) combined with meteorological, topographic, and hydrological data, including surface water and groundwater data. Vegetation was distributed in areas with high surface water frequency, shallow groundwater levels, relatively flat terrain, and dune basins. NDVI datasets show greening trends in oasis areas over the past 20 years. The frequency of surface water distribution influences water accessibility and effectiveness and shapes topography, thus affecting the spatial distribution pattern of vegetation. In this study, areas of high surface water frequency corresponded with vegetation distribution. The spatial distribution of groundwater depth supports the growth and development of vegetation, impacting the pattern of vegetation growth conditions. Vegetation is most widely distributed in areas where the groundwater burial depth is 3.5–4.5 m. This study provides data for restoring riparian vegetation, ecological water transfer, and sustainable development. [ABSTRACT FROM AUTHOR]

Multiple soil and water conservation measures applied together perform better at reducing runoff and sedimentation than individual measures, which can be attributed to their synergistic effects on water erosion. However, whether these synergistic effects are always effective at reducing water erosion remains unclear. In this study, a series of physical models representing a slope‐gully system were tested to quantify the trend of synergistic effects of multi‐measure over time through simulated rainfall. The tested scenarios included four vegetation patterns on the slope—Pattern A: no grass, Pattern B: grass on the up‐slope, Pattern C: grass on the middle‐slope and Pattern D: grass on the down‐slope—and five levels of runoff path length decrease (RPLD) in the gully caused by sedimentation of a check dam (0, 1, 2, 3 and 4 m). Synergistic effects on runoff and sediment yields were influenced by vegetation patterns and RPLDs. Under the same vegetation patterns, synergistic effects increased with increase of RPLD. Under the same RPLD, the mean value of synergistic effects on runoff was in the following order: Pattern D (0.10%) > Pattern C (0.09%) > Pattern B (0.06%), and synergistic effects on sediment yields had a similar order: Pattern D (0.60%) > Pattern C (0.42%) > Pattern B (0.22%). Under Pattern B, based on the Mann–Kendall trend test, the synergistic effects on the runoff yields decreased over time. Contrastingly, under Patterns C and D, the synergistic effects on the runoff yields increased over time. The results show that the synergistic effect has time effect, and its change trend is related to vegetation patterns. Additionally, the results suggest that the middle‐ and lower‐slopes should be prioritized when restoring vegetation as the synergistic effects on runoff tend to increase when these have good vegetation cover. [ABSTRACT FROM AUTHOR]

Lift-off velocity, the wind speed at which a diaspore starts moving during secondary wind dispersal, representing diaspore mobile capacity, may greatly depend on vegetation where dispersal takes place. However, how vegetation structure influences lift-off velocity and which is the most important vegetation attribute remain unknown. The vegetation with various attributes (four coverages-0, 10 %, 20 % and 30 %, three life-form compositions-herb, shrub and herb + shrub, two vertical patterns-one and two layers, and two horizontal patterns-uniform and aggregated) were set up for the wind tunnel experiment. Diaspores of 30 species varied in wing loading, terminal velocity, mass, projected area, length, width, height, and shape index were selected to measure their lift-off velocity within various vegetation structures. Lift-off velocity significantly increased with the increasing vegetation coverage, in the case of any life-form composition, vertical pattern and horizontal pattern of vegetation. For the vertical pattern of vegetation, the lift-off velocity in one-layer vegetation was significantly higher than that in two-layer vegetation, but only for 10 % vegetation coverage. Both the life-form composition and the horizontal pattern of vegetation had no influences on lift-off velocity. The correlation between lift-off velocity and diaspore attributes (length, width, height, projected area, mass and wing loading) increased with vegetation coverage and the correlation in two-layer vegetation was larger than that in one-layer vegetation. Our results indicate that vegetation coverage is the key vegetation attribute determining lift-off velocity during secondary wind dispersal. Lift-off velocity is also influenced by diaspore traits, but their relationships tend to be regulated by vegetation attributes, especially the coverage and vertical pattern of vegetation. Our study demonstrates the important role of vegetation coverage in determining the second dispersal capacity, which is helpful to understand the dispersal strategies of plants in response to vegetation structure and succession.

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[Objective] Studying the relationship between micro-topography and erosion under vegetation pattern can provide theoretical reference for the study of slope erosion law and soil and water loss control in feldspathic sandstone area. Methods] Slopes with three planting patterns (uniform distribution, aggregation distribution, random distribution) in BaoJia watershed in feldspathic sandstone areas were selected as the research sites. Field measurements in runoff plots under the condition of natural rainfall and 3T) laser scanning technology were jointly used, to analyze the influence of the vegetation pattern of microtopography and erosion. ResultsJ After rainfall, the order of discharge and sediment yield on different vegetation patterns was bare slope>aggregate sloped random slope>uniform slope. Compared with bare slope, discharge and sediment yield on uniform slope decreased by 64% and 75%, respectively. The fitting function of runoff and sediment is 丫 = ().361 9无, R'=().9866. There were some differences in the spatial distribution of erosiondeposition on slopes with different vegetation patterns. Compared with other slopes, the soil erosion intensity of homogeneous slope was the weakest, the erosion area was the smallest (1 2.38 m2), and the sediment area was the largest (3.44 ni'). The slope topographic factors of different vegetation patterns showed the increasing trend with rainfall, and compared with bare slope, increments of the surface roughness, surface undulation, surface cleanness and micro-slope were the least, which were 5 %, 2 %, ().5% and 9 %, respectively. The correlations between surface roughness and runoff and sediment yield were ().632 and ().619, respectively. Compared with other slopes, the fitting effect of topographic factors on bare slope and sediment yield was the best. The fitting functions of runoff and sediment were expressed as X = 0. 993R A 一1. ()7R + (). 871, R2 = ().996, Y= 1.586RA一().621?+2.65=().964, respectively. [Conclusion] The uniform distribution pattern has the best inhibition effect on soil erosion on feldspathic sandstone slope under hydraulic erosion condition, but the fitting effect is the worst. The interaction between micro topographic factors and sediment production and drainage is the most complex. [ABSTRACT FROM AUTHOR]

Climate change has become increasingly severe, threatening ecosystem stability and, in particular, biodiversity. As a typical indicator of ecosystem evolution, vegetation growth is inevitably affected by climate change, and therefore has a great potential to provide valuable information for addressing such ecosystem problems. However, the impacts of climate change on vegetation growth, especially the spatial and temporal distribution of vegetation, are still lacking of comprehensive exposition. To this end, this review systematically reveals the influences of climate change on vegetation dynamics in both time and space by dynamical modeling the interactions of meteorological elements and vegetation growth. Moreover, we characterize the long-term evolution trend of vegetation growth under climate change in some typical regions based on data analysis. This work is expected to lay a necessary foundation for systematically revealing the coupling effect of climate change on the ecosystem. • This review systematically reveals the influences of climate change on vegetation dynamics in both time and space. • We explain the formation mechanism of vegetation patterns using mathematical model and actual data. • We characterize the long-term evolution trend of vegetation growth under climate change. [ABSTRACT FROM AUTHOR]

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Philaenus spumarius (Linnaeus 1758, hereafter Ps) is considered one of the main insect vectors responsible for the spread of an alien biota, Xylella fastidiosa (Wells 1987, hereafter Xf), in the Salento area, Apulia region (Southern Italy). Effective management of this biological invader depends on the continuous surveillance and monitoring of its insect vector. As such, this research elicits the invasion drivers (i.e., landscape and vegetation indicators) that influence the abundance and the dynamics of this vector and, consequently, the spatial spread of this bacterium in this Italian region. For this purpose, a spatial pattern clustering methodological approach is considered. The results reveal that spatial variation and territorial differentiation may differ from zone to zone in the same invaded area, for which effective management and monitoring planning should be addressed. Further, six agro-ecosystems zones have been identified with respect to five indicators: (i) vegetation index, (ii) intensity of cultivation, (iii) cultural diversity, (iv) density of agricultural landscape elements, and (v) altitude. This paper has public implications and contributes to an understanding of how zoning of an infected area, by an alien biota, into homogenous zones may impact its effective management costs. This approach could also be applied in other countries affected or potentially affected by the phenomenon of Xf invasion. [ABSTRACT FROM AUTHOR]

The characteristics of soil holding capacity for different shrub-grass patterns are important to research the mechanisms regulating vegetation on slopes. The objective of this study was to describe the characteristics and mechanisms of soil erosion and hydraulic parameters under different vegetation patterns in the Pisha sandstone area of Inner Mongolia on lands of 8° slope gradient. We carried out field scouring experiments on five different shrub-grass patterns as treatments, viz no shrubs (GL), shrubs on the upper part of the slope (SU), middle part of the slope (SM) and lower part of the slope (SL). We designated bare slope (BL) as the control. We employed three different water flow rates (15, 20, 30 L·min−1). Our results showed that the contribution of plant root systems to slope sediment reduction ranged from 64 to 84%. The root systems proved to be the main contributing factor to reduction of erosion by vegetation. The relationship between soil detachment rate, stream flow power, and flow unit stream power under different scouring discharge rates showed that soil detachment declined in rank order as: BL > GL > SU > SM > SL. The SL pattern had the lowest soil detachment rate (0.098 g·m−2·s−1), flow stream power (2.371 W·m−2), flow unit stream power (0.165 m·s−1) and flow shear stress (16.986 Pa), and proved to be the best erosion combating pattern. The results of decision coefficient and path analysis showed that stream power was the most important hydraulic parameter for describing soil detachment rate. The combination of stream power and shear stress, namely Dr = 0.1ω − 0.03τ − 0.56 (R2 = 0.924), most accurately simulated the soil detachment characteristics on slopes. Our study suggests that the risk of soil erosion can be reduced by planting shrub-grass mixes on these slopes. Under the conditions of limited water resources and economy, the benefit of sediment reduction can be maximized by planting shrubbery on the lower parts of slopes. [ABSTRACT FROM AUTHOR]

Aim: Fungal 'fairy rings' (FRs) are regular bands of vegetation caused by a centrifugal expansion of fungal mycelia. It is well established that FR fungi affect both soil chemistry and microbiome, but nothing is known about the distribution of these patterns at the regional scale. Here, we assess the abundance and occurrences of different FR shapes i.e. rings, arcs and rotors, and explore their association with geomorphology and climate. Location: The Apennine Mountains, 300‐km latitudinal gradient along the Italian Peninsula. Taxon: Basidiomycetous fungi. Methods: High‐resolution freely available images were gathered to study FR shapes and distribution in the Apennine region of Italy. First, 12 mountains with different elevations and geomorphology were studied to assess the colonial density and relative distribution of FR type. FR distribution and shape and size of additional 616 FRs were studied in 61 study sites and relationship with selected climatic and topographic variables were assessed using different modelling approaches. Results: Overall, 1163 FR structures were found across the study area. Arcs were the most common shape followed by rings. Rotors were rare, accounting for less than 2% of all observations. Fungal colony density varied largely both among and within sites, averaging 6.7 arcs, 2.2 rings and only 0.1 rotors per ha. On average, arcs (18.8 m) were similar in size compared to rotors (18.4 m) whilst rings were smaller (11.7 m). Arcs presented a higher frequency of occurrence on steeper slopes whilst rings were mostly found on flat and moderate slopes. FRs occurred within the altitudinal range between 546 m and 2148 m a.s.l., corresponding to temperatures between 3.4 and 12.7°C and rainfall between 1100 and 1300 mm per year. Main Conclusions: FRs are common elements of the Apennine grassland landscape where they may contribute to the maintenance of plant and microbial diversity. Better systematic identification of the fungal species involved in the formation of FRs is required. Further research that combines long‐term field manipulative experiments and modelling work would help to explain the formation of rings, arcs and rotors during the ontogenetic development of fungal fronts. [ABSTRACT FROM AUTHOR]

Aeolian activity is common on ice free areas in regions with permafrost occurrence. Sparse high-Arctic tundra vegetation, modifying surface air flow and sediments transport, influences the generation of individual landforms and their assemblages. Observations were carried in central Spitsbergen (Svalbard), characterized by quasi-continental polar climate conditions with dry summers and common existence of winds velocities above loamy-sandy sediments transportation threshold. Dryas aeolian landforms created from aeolian material trapped by Dryas octopetala dwarf shrub were diagnosed. Main morphogenetic plants are accompanied by Saxifraga oppositifolia and Bistorta vivipara, rounded out with biological soil crust. Small size of semi-circular and semi-elliptic forms (0.25–0.85 m2) is related to low type of D. octopetala slowly growing on raised marine terraces. Aeolian sediments are characterised by low level of organic matter content. They exhibit diversified mineralogical composition resulting from variable petrography of source glacial and fluvioglacial covers. Eightpetal mountain avens are a dendroflora species composing phytocoenoses of plant communities related to the end stages of biocoenotic succession. Presented data indicate the reference environmental state for any research on plant cover response in the environment of aeolian activity during climate change.

Dust emissions by wind have significant implications for human health and ecosystems. The addition of effective materials in degraded soils is a suitable method for stabilizing soil accumulation, which can lead to reduced dust emission. To investigate the effect of biocharand vegetation on soil improvement against wind erosion, a wind tunnel experiment was conducted. This study was carried out in order to investigate the effect of walnut wooden shell biochar (Juglans regia L.) walnut wooden shell powder and three patterns of vegetation including raw, random and zigzag, on the soil erosion of Shahrekord plain soil which is one of the dust source. Biochar and walnut wooden shell in 5% by weight in separate soils were tested in a 60 - day period in the simulated wind tunnel, along with three artificial vegetation patterns. The results showed that soil modification can indirectly control the wind erosion potential. The amount of soil erosion in day 60 of experiment was 1455 g/m2 for control sample, 1270 g/m2 for raw pattern, 840 g/m2 for random pattern and 397 g/m2 for zigzag pattern, that zigzag pattern caused more reduction in soil erosion in comparison with other patterns. Biochar and walnut wooden shell powder resulted in 46.82% and 24.14% in formation of flocculed soil, respectively, in comparison with control sample, which increased resistance to soil erosion. As a result, biochar and powder along with vegetation are able to stabilize the soil and increase soil stability and lead to a reduction in wind erosion.

Regular pattern is a typical feature of vegetation distribution and thus it is important to study the law of vegetation evolution in the fields of desertification and environment conservation. The saturated water absorption effect between the soil water and vegetation plays an crucial role in the vegetation patterns in semi-arid regions, yet its influence on vegetation dynamics is largely ignored. In this paper, we pose a vegetation-water model with saturated water absorption effect of vegetation. Our results show that the parameter 1/P, which is conversion coefficient of water absorption, has a great impact on pattern formation of vegetation: with the increase of P, the density of vegetation decrease, and meanwhile it can induce the transition of different patterns structures. In addition, we find that the increase of appropriate precipitation can postpone the time on the phase transition of the vegetation pattern. The obtained results systematically reveal the effect of saturated water absorption on vegetation systems which well enrich the findings in vegetation dynamics and thus may provide some new insights for vegetation protection.

Aim: Perennial plant communities are crucial for regulating ecological processes and maintaining ecosystem functions. Variation in community structure is driven by both biotic and abiotic factors, reflecting adaptation strategies of plant communities to various environments. Although much is known about the response of individual perennial plants to drier climates, empirical evidence of the community‐level responses to increasing dryness is limited. Location: Eastern Australia; 1500 km gradient. Taxon: Perennial plants. Methods: We measured the abundance and size distribution (median, skewness and variance) of perennial plant communities from different growth forms (trees, shrubs and grasses), the spatial arrangement of trees in the overstorey and both biotic (competition) and abiotic (climate, soil properties) factors at 150 sites along an extensive aridity gradient from humid to arid areas. We used regression analyses and linear models to explore variation in community structure with increasing aridity and key driving factors for different perennial plant communities. Results: Variation in community structure differed with growth form. As aridity increased, trees had wider canopies and were spatially aggregated, shrubs became miniaturised, but highly variable in size, and grasses comprised more larger individuals. Biotic and abiotic factors exerted different effects on different growth forms, with trees and shrubs consistently affected by competition and aridity, respectively, whereas grasses were weakly affected by aridity, summer rainfall and soil texture. Main conclusions: Our study highlights the idiosyncratic adaptation strategies used by trees, shrubs and grasses in response to drying climates at the community level through their effect on the size distribution or spatial aggregation. The structure of different perennial growth forms was influenced by different effects from either biotic (competition) or abiotic (climate, soil) factors. Under forecasted drier climates, canopy expansion and greater aggregation of trees might enhance resource sinks and shelter for diverse biota, potentially shielding plant communities against predicted aridification. [ABSTRACT FROM AUTHOR]

The Nigerian environment changes due to humanity's anthropogenic activities. This study assessed the dynamics of land cover in Nigeria. Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI C6 (250 m) and Landsat (30 m) images were acquired and processed. The results from the MODIS images indicated that the vegetation in several hot spots had changed over decades across Nigeria; two of these hot spots, one in the Northeast and one in the Southwest, were selected for further assessment using the Landsat images. From these, results indicated that there was an increase in the Woodland/Gallery Forest by 3.51 percent and a decrease in Sand Dunes by 3.42 percent between 1987 and 2018. In addition, in the Southwest, there was a decrease in the Less Dense Forest by 33.8 percent and an increase in the Built-up area by 22.8 percent between 1986 and 2016. This study concluded that some intervention projects adopted by the government of Nigeria to address the challenges of desertification and deforestation in the Northeast yielded some positive impacts; however, the case is different in the Southwest, and its vegetation has been depleted at an alarming rate. [ABSTRACT FROM AUTHOR]

The Loess Plateau has long been suffering from serious soil erosion of which erosion from the slope-gully system is now dominant. The slope-gully system is characterized with distinctive erosion distribution zones consisting of inner and inter gully areas wherein erosion patterns spatially vary, acting as both sediment source and the dominant sediment and water transport mechanism. In this paper, a substantial body of research is reviewed concentrating on the soil erosion processes and control practices in the slope-gully system. The inner gully area is identified as the main sediment source while runoff and sediment from the inter-gully upland is found to significantly affect down slope erosion processes. Correspondingly, the protective vegetation pattern and coverage should be strategically designed for different erosion zones with an emphasis on the critical vegetation cover and pattern to reduce sediment yield of the whole slope-gully system. Check-dam could change the base level of erosion and reduce the slope length of the gully side, which will further decrease the possibility and magnitude of gravity erosion. We concluded that understanding the erosion processes and implementing erosion practices for the slope-gully system are of importance and require more research efforts that emphasize: 1) the influence of upland runoff on erosion processes at downslope; 2) the relationship between hydraulic characteristics of overland flow and erosion process at a slope-gully system scale; 3) physical mechanisms of different vegetation patterns on the slope-gully erosion process.

Introduction: Accurate identification of the dominant factors affecting coastal wetlands can provide a reference for vegetation rehabilitation. In this study, quantitative analysis was performed on the Yancheng coastal wetland using ANOVA and geostatistical methods. Outcomes/other: The results indicated that in the directions perpendicular and parallel to the coastline, the soil moisture and salinity in the study area exhibited relatively significant (p75%) for soil moisture and salinity in the southern experimental zone and southern buffer zone. Conclusion: Compared with the northern study area, the contribution of human disturbance to the spatial heterogeneity of soil moisture and salinity in the southern study area is higher.

Dolines are local depressions of karst surfaces. They can be considered potential microrefugia for various species. We investigated the species composition and vegetation pattern of two medium-sized dolines in Hungary before and 10 years after logging, and analysed how different species groups (oak forest species, beech and ravine forest species and disturbance-tolerant species) were affected. The cover and number of oak forest species and disturbance-tolerant species increased, while the cover and number of beech and ravine forest species decreased within dolines due to logging. Therefore, their species composition and vegetation pattern have changed substantially, and dolines have partially lost their capacity to act as safe havens for plant species adapted to cooler conditions.

Question: In the fall 2018 we observed an atypical pattern with concentric belts of green, yellow, and brown vegetation. What are the causes of the pattern? Localized water depletion, soil spatial heterogeneity and the activity of pathogenic organisms were tested as alternative hypotheses. Location: Banks of a water reservoir, Alento basin in south Italy (40°19′04.50″ N; 15°06′45.35″ E). Methods: Belts were monitored for floristic composition and plant health status. In each zone, 17 soil parameters were analysed (soil texture, pH, electrical conductivity, limestone content, organic C, Olsen P, total N, C/N ratio, cations exchange capacity, Ca2+, Mg2+, Na+, K+, Fe, Cu, Zn, Mn). Soil moisture was monitored by soil probes, positioned at 10 cm depth. The incidence of pathogens and parasitic plants was visually estimated. Finally, model simulations were carried out to explore the interactions between biotic and abiotic factors in the formation of the belts. Results: The vegetation survey revealed that the green belt was characterized by a monospecific stand of Xanthium italicum with a plant density >190 individuals per m2. All plants were healthy. In the yellow belt, instead, Xanthium italicum was attacked by the parasitic plant Cuscuta campestris with an incidence >70%. In the brown belt all Xanthium italicum was still standing but dead, with an incidence of Cuscuta campestris attack >94%. No differences in soil chemistry were recorded in the three belts, while soil moisture was slightly lower in the green belt, likely as a result of a higher evapotranspiration rate. The modelling simulation well reproduced the banded vegetation, supporting the role of the parasitic plant in the formation of the pattern. Conclusions: By combining extensive field measurements with detailed modelling work, we revealed, for the first time, the primary role of a parasitic plant in the formation of a regular and ephemeral vegetation pattern. [ABSTRACT FROM AUTHOR]

Introduction: Accurate identification of the dominant factors affecting coastal wetlands can provide a reference for vegetation rehabilitation. In this study, quantitative analysis was performed on the Yancheng coastal wetland using ANOVA and geostatistical methods. Outcomes/other: The results indicated that in the directions perpendicular and parallel to the coastline, the soil moisture and salinity in the study area exhibited relatively significant (p<0.05) spatial variability. Vegetation in the southern experimental zone was in a low-moisture, low-salinity ecological niche, whereas vegetation in the northern experimental zone was in a high-moisture, high-salinity ecological niche. Soil salinity exhibited higher spatial variability than soil moisture, and it was most correlated with unvegetated mudflats, followed by areas with Spartina alterniflora, Suaeda glauca, and Phragmites australis. Discussion: The fitting of the semivariogram showed that the nugget and sill of the ratio were relatively low (<25%) for soil moisture and salinity in the northern experimental zone and northern buffer zone, whereas these values were relatively high (>75%) for soil moisture and salinity in the southern experimental zone and southern buffer zone. Conclusion: Compared with the northern study area, the contribution of human disturbance to the spatial heterogeneity of soil moisture and salinity in the southern study area is higher. [ABSTRACT FROM AUTHOR]

Dust emission from wind erosion is a widespread phenomenon in arid and semi‐arid areas having considerable implications for ecosystems and human well‐being. However, few studies have examined the efficiency of biochar amended to soil on wind erosion control. Aimed at studying the effect of biochar on resistance of soils against wind erosion, a wind tunnel experiment was conducted. We tested (a) soils amended with hard waste walnut wood biochar and soft maize cob biochar, and (b) soils amended with powdery waste wood and powdery maize cob, and compared them with (c) non‐treated soil, in their susceptibility to wind erosion and also the additional effect of various patterns of vegetation cover. Amending soil with biochar and powdery material did significantly increase their resilience to wind erosion because of increased soil aggregation. In comparison with the non‐treated control, the mass flux of un‐vegetated soil reduced from 4.42 to 1.86 g m−2 s−1 for the waste walnut wood biochar, from 4.28 to 1.50 g m−2 s−1 for maize cob biochar, from 4.11 to 1.44 g m−2 s−1 for powdery maize cob and from 3.97 to 1.14 g m−2 s−1 for powdery waste walnut wood. When combining amendments with vegetation, there was still a substantial improvement, though the soil treatments responded differently in terms of soil loss to different vegetation patterns. A single row vegetation pattern had the highest mass flux, while a zigzag vegetation pattern had the lowest. In conclusion, waste wood or maize cobs, whether applied as biochar or as powdery material, are able to fix soil and reduce wind erosion. [ABSTRACT FROM AUTHOR]

• A CA-based model of slope soil erosion was constructed to simulate complex spatiotemporal dynamic behaviors and processes. • A simulation model was developed for the transition between various types of soil erosion intensity. • To predict the development trend of soil erosion in different regions under different rainfall conditions. • Based on transition probability matrix and suitability map, the future trend of slope soil erosion intensity was simulated. The study of soil erosion is significant to soil and water conservation and ecological construction planning. CA, a dynamic modeling method, has been widely used to simulate the future changes of soil erosion intensity. In this study, three slopes with different vegetation patterns (uniform distribution, aggregated distribution, and random distribution) and a bare slope in the Baojiagou watershed in the Pisha sandstone area were taken as the study objects. Based on the soil erosion intensity grade maps of slopes with different vegetation patterns under the three periods of rainfall, the soil erosion intensity grade maps of the four slopes were simulated by combining multi-criteria evaluation (MCE) and Markov chain (CA-Markov). Through tests, the Kappa coefficients of the simulated maps of uniform distribution, random distribution, aggregated distribution and a bare slope reached 80.15%, 75.41%, 75.92% and 76.48%, respectively. The results revealed that the soil erosion types on slopes with different vegetation patterns were transferred differently, and fewer erosion areas were generally transferred into highly eroded ones, with moderately and slightly eroded areas as the main transfer flows. After simulating the grade map of soil erosion intensity on slopes with different vegetation patterns, it was found that the slopes with uniform and random vegetation distribution primary displayed the transfer from highly eroded areas to less eroded ones, and the sedimentary area was enlarged, while the slope with aggregated vegetation distribution and the bare slope mainly presented the transfer from less eroded areas to highly eroded ones. The sedimentary area was diminished. Therefore, compared with the bare slope, the slopes with uniform and random vegetation distribution exerted a better inhibitory effect on the soil erosion degree of hydraulically eroded slopes, and the inhibitory effect of aggregated vegetation distribution-type slope was the weakest. The study results provide critical information for planning and implementing soil conservation measures in the study area. [ABSTRACT FROM AUTHOR]

In this paper, a diffusive vegetation-water model under Neumann boundary conditions is considered. Firstly, the stability and the diffusion-induced Turing instability are studied. Then, some a priori estimates of positive steady-state solutions are obtained by the maximum principle. Moreover, the bifurcations at both simple and double eigenvalues are investigated in detail. Finally, numerical simulations are shown to support and supplement theoretical analysis results. In particular, the evolution processes of vegetation patterns are depicted under different parameters. [ABSTRACT FROM AUTHOR]

The establishment and maintenance of tidal marsh ecosystems depends upon multiple interactions between tidal hydrology, local soil surface elevation, plant productivity, and regional salinity. The nature of these interactions, their relative influence on the character of the tidal marsh ecosystem, and their importance in determining the vegetation pattern on the landscape is not clearly understood. The research presented in this dissertation had four objectives: 1) to demonstrate the dependence of vegetation pattern on tidal channel hydrology: 2) to demonstrate that the strength of dependence of vegetation pattern on tidal channels changes with salinity: 3) to characterize the nature and quantity of the patterns of sedimentation within tidal marshes, and; 4) to provide conceptual models for understanding how physical and biological factors interact to produce and maintain tidal marshes, with an emphasis on aiding programs of tidal marsh restoration within the San Francisco Bay/Delta Estuary.