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Pollen-based vegetation, biodiversity, and biome reconstructions over the last 15,500 years from sediment core data at Mbi Crater in the Cameroon highlands (6.089273° N, 10.348549° E; 2015 m above sea level) are used to discuss the behavior of the lower edge of the Afromontane forest facing climate change. The data reveal that the post-glacial forest change gradually happened at Mbi and that the forest-wooded grassland ecotone was highly influenced by the climate variability related to the North Atlantic. The forest disruption and diversity loss intermittently occurred over the whole period, and their vegetation changes temporally match dry-cold events at the northern latitudes during the Younger Dryas, at 9.5–9.1 ka, 8.6–8.0 ka, 6.7–6.0 ka, 3.2 ka, and during the Little Ice Age (LIA). During the LIA, the mountain forest was subject to unprecedented levels of disturbance at all altitudes, unlike the seasonal lowland forests, which appears to have been only marginally affected.

International audience; While the emergence of the Acheulean is well documented in East Africa at ~1.7 Ma, subsequent developments are less well understood and to some extent controversial. Here, we provide robust evidence regarding the time period between 1.6 Ma and 1.2 Ma, based on an interdisciplinary approach to the stratigraphic sequences exposed in the Gombore gully of Melka Kunture, in the upper Awash Valley of Ethiopia. Throughout the Pleistocene, the environment differed significantly from elsewhere in Africa because of the elevation at 2000 m asl, the cooler and rainy climate, the Afromontane vegetation, the development of endemic animal species, and the recurrent impact of volcanic activity. At Gombore IB, dated ~1.6 Ma, remains of Homo erectus/ergaster have been discovered, associated with a rich early Acheulean assemblage. The techno-typological analysis of the lithic record from Gombore Iγ (~1.4 Ma) and Gombore Iδ (~1.3 Ma), where substantial areas have been excavated, and the contrasting evidence from Gombore OAM Test Pit C (~1.2 Ma), suggest that the scarcity or lack of large flakes and large cutting tools at the two earlier sites is possibly not just the outcome of sampling bias, but rather of the adaptation of H. erectus/ergaster to the local resources, in a relatively isolated environment. The sites of Gombore gully provide new evidence on the complex pattern of human evolution and adaptation in East Africa during the Lower Pleistocene.

This paper presents recently obtained palebotanical data regarding the evolution of Lake Paleolotos in the Middle Pleistocene. Its evolution was more complicated than the development of the adjacent lakes in the coast of Peter the Great Bay (the Sea of Japan). The Middle Pleistocene lacustrine sediments accumulated in the downstream of the Tumannaya River (the most southwestern area of Primorye, Russia Far East) were studied using diatom and pollen analytical methods. We found that the Lake Paleolotos arose during Marine Isotope Stage 11 (MIS 11) and disappeared during MIS 6. For more than half of its existence (MIS 11–8), it was a freshwater oligotrophic basin with a depth of at least 20 m, with clear waters and poor organic matter content. The lake occupied most of the modern accumulative plain on the left bank of the Tumannaya River, reaching a size of at least 10–12 km across. During MIS 7–6 Lake Paleolotos turned into a shallow-water basin (its depth most likely did not exceed 1–3 m) of a eutrophic type with turbid waters rich in organic matter. Palynological data suggest that during MIS 11, 9 and 7 the area adjacent to the Lake was covered with coniferous/broad-leaved forests with presence of some thermophilic plants of North China and North Korea Flora (Castanea, Celtis, Magnolia, Tsuga and Cupressaceae). This indicates that vegetation zones were displaced by about 500–700 km to the north relative to their present position. During periods of cooling they were replaced by coniferous/small-leaved forests with the participation of shrub species of birch and alder (MIS 10) and coniferous/small-leaved forests consisted of pine, birch, and spruce with the participation of elm and oak (MIS 8 and 6).

The vicinity of the Rozprza archaeological site (central Poland) has been the area of a series of palaeoecological studies tracking the environmental history of the Luciąża River valley up to ca. 13,200 cal. BP. Numerous subfossil palaeomeanders of different sizes have been discovered in the valley floor. Here, we present the first results of multiproxy research on the paleo-oxbow lake fill, one of the oldest in the region. The wide range of palaeoecological analyses resulted in reconstructions of vegetation history, climatic, hydrological and habitat changes. The studied oxbow was an aquatic ecosystem with diverse invertebrate fauna until the end of Younger Dryas when it transformed into a limno-telmatic habitat. The sediment composition indicates active denudation processes and several episodes of turbulent hydrological conditions. Such an increased river activity could have caused flooding, resulting in an allochthonous matter supply to the oxbow lake in Late Vistulian. Environmental changes were strictly related to the regional features of the catchment, the transformation of soils, and the hydrogeological conditions. The chironomid- and pollen-inferred climatic reconstructions indicate periods of high and low continentality. The chironomid record indicates relatively cool summer conditions in the Allerød, especially ca. 13,000 cal. BP, possibly related to the Gerzensee Oscillation. On the other hand, a distinct increase of summer temperatures in Younger Dryas (up to 16 °C) was recorded. Such a situation was also confirmed in some other studies from the region, suggesting that it might be the effect of some specific, local palaeoclimatic conditions. Fundator badań: Fundator badań: Optional.empty

The study was designed to document the phytodiversity and vegetation dynamics of Chour Valley, Hazara Division, Pakistan during 2018–19. Sum of 115 plant species belonged to 48 families were documented. The leading family was Rosaceae with 14 plant species followed by Asteraceae (11 species). The data were analyzed for classification through two way indicator species Analysis and ordination through CCA and DCA to find differences in directories of plants communities and their habitats kind. Five plants communities were identified including, Abies-Pinus-Rheum, Picea-Cyperus-Oxalis, Rumex-Urtica-Cyperus, Picea-Betula-Viburnum and Berberis-Clematis-Potentilla communities. It was observed that the distribution of species and community structure was directly correlated to altitude, slope aspect and soil characteristics. It was also noticed that forest in the study area are continuously degraded and will go in vanishing, until conservation and restoration measures are adopted in priority basis.

Site preservation and associated terrain characteristics are among the major agents controlling the spatial distribution and discoverability of late Quaternary archaeological sites. However, site expectancy in extensive areas can be determined using a combination of geoarchaeological investigation and digital spatial analysis. In that sense a prediction model, respectively the result of a Multi Criteria Decision Analysis (MCDA), is presented to highlight areas with a high potential to contain Upper Palaeolithic sites in the Eastern Mediterranean and bordering arid margins. Based on detailed on-site analysis in the Wadi Sabra region, with its many sites and the location of other well-known sites in the southern Levant, eight individual parameters, aspect (cardinal point), elevation, geomorphology, hydrogeology, drainage network, slope inclination, vegetation, and a terrain ruggedness index (TRI) are evaluated and tested for significance. The statistical results confirm a significant divergence of the spatial distribution of Upper Palaeolithic sites from the distribution of natural terrain position factors. This allows for a definition of parameter classes with a high site expectancy and their use in a predictive model. For the results map, the site expectancy factors determined in this way were intersected with each other, thus enabling a distinction between areas with a high and low site occurrence probability. The accuracy of the presented result is assessed by the implementation of another MCDA pass based on an independent dataset of archaeological survey sites and compared to the original. Both datasets complement each other and can show the potential for further investigations with more numerous site datasets as well as more detailed spatial information. A local classification based on high-resolution elevation information and field data is evaluated for the Wadi Sabra, Southern Jordan, which can confirm yet further specify the result from the MCDA.

The lowest section of the Upper Dniester River Valley (DRV), located between the uplands of Opillia and Eastern Subcarpathians, was a separate and specific Pleistocene geoecosystem, interesting for the hunter-gatherer communities. This is evidenced by three main (Yezupil, Mariampil and Halych), and a dozen or so additional Palaeolithic open-air sites. They occur as cultural layers within the loess-palaeosol sequences (LPSs) and represent semi-permanent settlement (except for the periods with the maximum intensity of the loess sedimentation); the oldest occur in the Eemian palaeosol. All sites are located on both sides of the river. In the past, the DRV was characterized by local environmental diversity changing with time. In consequence, it has very individual features, so the analysis of environmental changes is a local case study. In order to obtain information about the changes of climate and environment, the multi-proxy analyses were carried out. Chronology was based on the luminescence and radiocarbon dating. The diversity of habitats was local. Its degree was changing with time: it was minimal in the periods with extreme climatic conditions, such as the climate optimum and pessimum, and clearly greater in the climatically intermediate periods with fluctuations. Based on the materials indicating the mesoclimate and local vegetation diversity during the human occupation episodes as well as the location of the Palaeolithic sites, we found that generally the possibilities of choosing a warmer or sheltered place for a camp were not significant for hunters representing different cultures of different ages. Palaeolithic groups very often occupied the same places in the DRV. The camps had a hunting function, the choice of places was dictated primarily by the need to find a good place to observe game animals and to organize hunting – first of all – in the mouth sections of the tributaries of the Dniester River, regardless of the situation of localities relative to riverplains. The settlement attractiveness of such places was essentially timeless.

Desertification in degraded grasslands is manifested through the development of bare sandy patches, which eventually lead to habitat fragmentation. The ability of these bare sandy patches to regenerate naturally through in-situ soil seed banks is not well understood. To fill this knowledge gap, we randomly selected 24 bare sandy patches with areas ranging from 19 to 898 m2 in a desertified grassland of the Horqin sandy land, Northern China to determine whether soil seed bank can be used for natural regeneration of bare sandy patches. Species composition and density of soil seed bank as well as aboveground vegetation composition, abundance and coverage were investigated. We then determined their relationships with in-situ habitat characteristics. Our observations showed that the studied area had low soil seed bank density and species richness, as well as depauperate soil seed bank communities. Consequently, local soil seed bank was not able to provide sufficient seed source for natural regeneration. This was indicated by the relationships between aboveground vegetation, soil seed bank and the in-situ habitat characteristics. For bare patches with an area between 300 m2 and 900 m2, increase the soil seed bank density and species richness should be the main restoration measures. For bare patches with a small area of less than 50 m2, restoration of vegetation density should be the main measure. Our data highlighted that different extents of desertification, indicated by different bare patches, are requiring distinct restoration measures.

Early Eocene climate and vegetation evolution in northern Yakutia (Eastern Siberia) are quantitatively studied for the first time based on paleobotanical records, using the coexistence approach (CA) for paleoclimate, the plant functional type approach (PFT) and the integrated plant record method (IPR). Paleobotanical data of this time-interval were obtained from 18 palynofloras of the coal beds outcropping on the bank of the Bykovskaya Channel in the area of Bulunkan Bay (Lena River Delta). The results indicate the persistence of warm temperate and at times possibly nearly tropical, overall humid climate conditions throughout the early Eocene, and a relatively strong seasonality in precipitation. The vegetation reconstructed is in agreement with the climate conditions determined by the CA. Analyses of the PFT diversity spectra indicate the prevalence of mixed warm temperate evergreen-deciduous forests. Based on the IPR method, plant biomes varied from mixed mesophytic forests during warmer intervals to broadleaved deciduous forest/mixed mesophytic forest ecotone during cooler episodes. The presence of mangroves in our early Eocene records is possibly related to hyperthermal events such as the Paleocene–Eocene Thermal Maximum.

We compiled the Cretaceous sporopollen fossil data from 19 locations of six provinces in South China, reviewed the affinities of spore and pollen genera by examining and assessing these fossils with published data, and associated them with the sporomorph eco-groups (SEG) model and vegetation type. Seven palynofloral assemblages (PA1–PA7) were identified. PA1 (Berriasian–Valanginian) and PA2 (Hauterivian–Barremian) mainly include Cheirolepidiaceae (∼60–80%), Cycadophytes (∼10%), and Lygodiaceae (∼10%), indicating warm and dry climate; PA3 (Aptian) and PA4 (Albian) represent warm, semi-arid to semi-humid climate with vegetation composed of Araucariaceae (∼10%), Cheirolepidiaceae (∼40–60%), Cycadophytes (∼10%), and Lygodiaceae (∼10%); PA5 (Cenomanian–Turonian) and PA6 (Coniacian–Santonian) imply a hot, semi-humid to humid climate with the vegetation taxa of Lygodiaceae (∼20–40%), Cheirolepidiaceae (∼20–50%), Ephedraceae (∼5–8%), and Araucariaceae (∼10%); and PA7 (Campanian–Maastrichtian) indicates a relatively cool and dry climate evidenced by the vegetation composition of Cheirolepidiaceae (∼30–40%), Pteridaceae (∼10%), Ephedraceae (∼5–8%), and Ulmaceae (∼30–40%). Our SEG analysis reveals three climatic evolution phases: the Berriasian–Barremian warm-dry phase, the Aptian–Santonian warm-wet phase, and the Campanian–Maastrichtian cool-dry phase. The climatic variation pattern is compatible with that indicated by fossil stomatal pCO2 values and the pCO2 simulation of GEOCARB II and III models, providing independent climatic proxies of the region and contributing to better understanding of the global Cretaceous climatic changes.

Pollen, sediment texture, moisture, organic/inorganic carbon content and geochemical analyses of a 1.2m in-depth sediment profile from upper Tundabhuj Lake in the Parvati Valley show that the region supported alpine-scrub vegetation. The forest elements largely consisted of Betula and its broad-leaved allies viz., Quercus, Corylus and Carpinus interspersed with meadow grasses, Asteraceae, Impatiens, etc. under a warm and moderately humid climate from around 17,100 to 14,700 cal yr BP. Additionally, the increase in organic carbon, enrichment of immobile elements (TiO2, Al2O3, Fe2O3) and moderate values of the Chemical Index of Alteration (CIA = ~72) reinforce the warm and moderately humid climate in the catchment. Subsequently, at around 14,700 to 10,600 cal yr BP, an increase in alpine-scrub vegetation dominated by Betula, Corylus and Carpinus was observed. The enrichment of (TiO2, Ni and Cr) and slightly higher CIA values (72–78) indicated relatively more humid conditions than earlier climatic conditions. The climate turned cold and dry between 10,600 and 5400 cal yr BP as deduced from the abrupt reduction in the alpine-scrubs and meadow constituents. During this period immobile elements (Al2O3, TiO2, Fe2O3, and Cr) also decreased. In contrast, mobile elements (CaO, Na2O, Sr, and Ba) increased along with a gradual decrease in CIA (minimum at 42.5 cm) and organic carbon content supporting cold and dry climatic conditions. From around 5400 until ~1600 cal yr BP, the region saw a return of alpine-scrubs and conifers, indicating a relatively warm and humid climate. Increasing CIA values, organic carbon, and concentration of immobile elements also reaffirm relatively warm and humid climatic conditions. In the most recent phase (around 1600 cal yr BP to present), the climate deteriorated as reflected by the depletion of Betula and broad-leaved associates and an increase in dry elements such as Juniperus and Ephedra. The decrease in CIA values, organic carbon and immobile elements (TiO2, Al2O3, and Fe2O3) substantiate this observation.

Detailed knowledge of the periglacial flora is essential to assess the vegetation dynamics in deglaciated regions of northern and north eastern Europe, previously covered by the ice sheet of the Late Weichselian Glaciation. Therefore, the territory of Belarus, which stretches in the periglacial zone of the Last Glaciation and the most part of which was free of ice during the Last Glacial maximum, is off particular importance in analysing the postglacial floral establishment and the subsequent vegetation dynamics in this part of the continent. In this study, results of palaeobotanical (pollen and plant macrofossil), lithological (measurements of magnetic susceptibility, MS) and isotopic (14C) investigations were obtained to fill the existing gap in reconstructing the peculiarities of the terrestrial and aquatic vegetation dynamics throughout the Lateglacial - Early Holocene period in the central Belarus. The investigated sediment profile, comprising organically enriched gyttja at 13,400–13,100 cal yr BP, carbon enriched and sandy gyttja at 13,100–9700 cal yr BP and unconsolidated mud after 9500 cal yr BP, provides clear evidence proving the flourishing of a pine-birch predominated forest with occasional spruce stands during the Allerod in area. Three occasions of change in the vegetation structure were noted within the Younger Dryas, i.e. 12,900–12,700 cal yr BP, 12,200–12,000 cal yr BP and 11,900–11,700 cal yr BP, suggesting negative climatic excursion taken place in area and facilitating flourishing of a Picea-predominating forest that culminated at about 12,300 and 12,000 cal yr BP. Pollen record suggests the Early Holocene vegetation shifts occurring at about 11,300–11,200 cal yr BP, 10,800–10,600 cal yr BP and 10,300–10,100 cal yr BP evidence the general response to the global-scale climatic events i.e. Preborael Oscillation or “10,2 ka” while fluctuations triggered by local or regional-scale climatic events have been identified as well. About 10,800–10,700 cal yr BP, formation of the forest with an increasing representation of thermophilous taxa (Ulmus, Tilia, Quercus) started in area.

Introduction There has been limited research conducted on the identifications/methodological approaches of using plant species as indicators of the presence of economically, important mineral resources. Objectives This study set out to answer the following questions (1) Do specific plant species and species assemblages indicate the presence of mineral deposits? and (2) if yes, then what sort of ecological, experimental, and statistical procedures could be employed to identify such indicators? Methods Keeping in mind these questions, the vegetation of subtropical mineral mines sites in northern Pakistan were evaluated using Indicator Species Analysis (ISA), Canonical Correspondence Analysis (CCA) and Structural Equation Modeling (SEM). Results A total of 105 plant species belonging to 95 genera and 43 families were recorded from the three mining regions. CA and TWCA classified all the stations and plants into three major mining zones, corresponding to the presence of marble, coal, and chromite, based on Jaccard distance and Ward’s linkage methods. This comprehended the following indicator species: Ficus carica, Isodon rugosus and Ajuga parviflora (marble indicators); Olea ferruginea, Gymnosporia royleana and Dicliptera bupleuroides (coal indicators); and Acacia nilotica, Rhazya stricta and Aristida adscensionis (chromite indicators) based on calculated Indicator Values (IV). These indicators were reconfirmed by CCA and SEM analysis. Conclusion It was concluded that ISA is one of the best techniques for the identification/selection of plant indicator species, followed by reconfirmation via CCA and SEM analysis. In addition to establishing a robust approach to identifying plant indicator species, our results could have application in mineral prospecting and detection.

The Loess Plateau is one of the most vulnerable areas in the world as it is extremely susceptible to soil erosion and ecological destruction. Recently, the local government carried out the “Gully Land Consolidation Project” (GLCP) in the Loess Plateau region to increase farmland area, improve rural production and living conditions. Among all the GLCP engineering constructions, slope protection engineering plays an important role in ensuring the safety of the main project, residential lives and properties, although more theoretical and technical research on comprehensive protection of engineering slopes is required. In this study, a field experiment using 12 standard runoff plots (length 4m×width 2m) was performed in Yangjuangou catchment of Yan'an City, to compare and analyze the comprehensive benefit to vegetative growth, soil erosion and engineering benefit from four vegetation styles and three levels of slope gradient (45°, 53°,63°). Results show that under different slope gradient and vegetation styles, significant differences existed in the comprehensive benefit to slopes, as well as the levels of vegetative growth, soil erosion and engineering benefit. The comprehensive benefit of the 53° slope was significantly better than that of 45° and 63° slopes. In addition, the comprehensive benefit of slopes with one or more vegetation styles was better than that of non-vegetation covered slopes. With the increase in slope gradient, the vegetative growth and slope erosion indices of vegetation average height, species richness, vegetation coverage slope, runoff production and sediment yield, showed a remarkable declining trend. Conversely, the engineering benefit index including newly-increased farmland area and excavating earthwork volume, showed an increasing trend. Recently, agricultural geographical engineering (AGE) has become an indispensable method for ecological construction and agricultural development, resulting in an increase in research in the field of geography. These findings not only have theoretical significance and enrich our understanding of the influence of gradient and vegetation styles on excavation slope protection, but also have practical significance and provide a baseline for engineering parameters and suggestions for slope protection engineering strategies.

The numerous lake and peat sedimentary archives of Central European Russia are ideal for studying the Lateglacial–Holocene climate and vegetation history of the region. However, robustly dated palaeoenvironmental records have only become available in the last decade and are still few and far between. Together with the continuously growing archaeological record and increasing focus on absolute dating of cultural assemblages, such records, where available, offer an excellent opportunity to study human-environment interactions in the region. For this study we selected one of the most detailed regional pollen records, from a 4.5-m-long sediment section from Zmeinoe Mire (56°16′53″ N, 31°15′36″ E) at Zhizhitskoye Lake (165 m a.s.l.). We performed quantitative pollen-based biome reconstruction and constructed a Bayesian age-depth model to ensure maximum chronological control of the sediment succession. To link the reconstructed vegetation changes to human activities, we gathered and summarized available archaeological data from the study area. Our results show that humid conditions and taiga-like patchy forests (spruce, pine, birch) dominated the study region during the Lateglacial. The Early Holocene (ca. 11,650–8000 cal yr BP) was marked by a warming and drying trend indicated by the spread of cool-temperate summergreen broad-leaved trees and shrubs (elm, lime, hazel) and the retreat of spruce. Warmest conditions, expressed by the maximum contribution of temperate deciduous woody taxa to the pollen assemblages, were recorded during the Middle Holocene (ca. 8000–4000 cal yr BP) when Mesolithic and Neolithic hunter-fisher-gatherer groups flourished in the region. The pollen record suggests that the regional climate became cooler and wetter after 4000 cal yr BP, which may explain the decline of the Neolithic pile dwelling settlement Naumovo at Zhizhitskoye Lake around 3800 cal yr BP. Evidence for human impact on natural forest vegetation becomes visible from 5000 cal yr BP, although it remains at modest levels until the end of the Neolithic (3500–3000 cal yr BP). Decline in arboreal pollen percentages intensified after ca. 2800 cal yr BP, indicating the onset of increased deforestation for pasture, farmland, construction material and fuel by Iron Age populations. This is in line with the foundation of the fortified Iron Age Anashkino settlement north of Zhizhitskoye Lake dated to around 2750 cal yr BP. Forest clearance further increased during the second half of the Iron Age (5th century BCE–5th century CE) and again from ca. 1200 cal yr BP after the onset of the Middle Ages.

This paper presents the results of the wood charcoal analyses from the Middle Paleolithic open-air site at Nesher Ramla, on the central coastal plain of Israel. The study focuses on the interpretation of the charcoals left by fires used by Middle Paleolithic hominins during early Marine Isotope Stage (MIS) 5. Moreover, this study sheds light on the arboreal taxa present in the vegetation and environmental conditions in the southern Levant during the Middle Paleolithic. A small quantity of identifiable charcoals was retrieved from the 8-m-thick archaeological sequence of the site (Units II to VI). The largest charcoal assemblage was recovered from part of the sequence dated to MIS 5e. The results show the presence of deciduous Quercus sp. and Prunus. The presence of these taxa, together with other proxies from the multidisciplinary studies at Nesher Ramla, indicate an arboreal setting with relatively humid and mild climatic conditions in MIS 5e. Our results further suggest that wood was used as fuel at Nesher Ramla. Given the scarcity of Middle Paleolithic sites in the Levant that have yielded charcoal, this new data from Nesher Ramla constitutes an important contribution to the study of past environments and the exploitation of plant resources by human groups.

Insights into the rates at which ecosystems and vegetation respond to a changing climate is fundamental to anticipating impacts of projected climate change. Characterization of vegetation change over millennia to centuries has potential to make an important contribution toward this goal, and regional scale syntheses of fossil pollen data can provide the foundation for this understanding. However, challenges of data analysis and integration are nontrivial. Here we present a case study in which publicly available fossil pollen data for California are assessed and analyzed. The data are selected according to a clearly defined selection criteria, and a Rate of Change (RoC) value is calculated to assess rates of vegetation change in California from ~15k BP (before A.D. 1950) to the present. Our results highlight several challenges presented by the extant data sets, including temporal sampling variation within and between records, large age control uncertainties, and sparse, geographically biased coverage. Recommendations for methodological refinements to better characterize ecological rates of change include increasing sampling frequency, maintaining a consistent temporal spacing within records, and applying probabilistic approaches to existing pollen data sets.

In arid-semiarid regions, understanding the mechanisms by which vegetation change and climate change affect the regional water balance is important for the development of effective measures and for guiding vegetation restoration and adapting to climate change. In this study, we utilize the Budyko equation and dual-source evapotranspiration models to assess the impacts of vegetation change and climate change on the runoff in China's Yellow River Basin (YRB). The aims of the study are as follows: (1) Apply a well-formulated Budyko framework-dual-source evapotranspiration model to explore the eco-hydrological controls of the regional water balance. (2) Precisely assess the contribution of vegetation change, precipitation change, temperature change, wind speed change, the relative humidity change, and radiation change to the decreased runoff. The results indicated that vegetation change was the dominant factor affecting the reduction of runoff in the upper reaches above Lanzhou, Toudaoguai, Longmen, Sanmenxia, and Huayuankou, and the contributions were −80.4%, −58.4%, −52.5%, −46.9%, −39.7%, and −41.6% respectively. In Lanzhou, Taodaoguai, Longmen, and Sanmenxia, the precipitation change was the second affecting factor, and the contributions were −20.8%, −31.6%, −30.0%, and −35.2%, respectively. In Huayuankou and Lijin, the relative humidity change was the second affecting factor, and the contributions were –26.8% and −35.0%, respectively. (3) As the vegetation coverage or the leaf area index (LAI) increased, the runoff decreased linearly.

This paper presents the first insight into the interpretation of the wood charcoal from the Holocene layers of Wonderwerk Cave. Situated in the Northern Cape Province in the arid interior of South Africa, the site provides a unique and valuable chronological record of past environmental fluctuations and responding human behavioural adaptations spanning the last two million years. The Holocene strata have been dated to cover the last 12.5 ka cal BP years, but exclude the last 100 years because of contamination. A sizeable amount of charcoal was recovered from these strata and remnants have been identified, described and the species composition amongst the strata compared. Most identified species are those that tolerate hot, dry conditions, signalling an arid trend during the Holocene. Comparison with present day species distributions suggests an eastwards shift in modern vegetation. The charcoal data also indicate that during the mid Holocene there was a wetter period from 6.2 to 4.5 ka cal BP, coinciding with stratum 4a.

In this study we investigate the timing and nature of moisture availability in the Late Holocene by examining a multiproxy paleoenvironmental record from Kathu Pan at the southern edge of the Kalahari. In a region where organic proxy records are scarce, Kathu Pan provides a unique record of changes in past environmental conditions. Pollen, spore, charcoal, and stable isotope records were obtained from organic deposits at Kathu Pan and examined within a radiocarbon-constrained chronological framework. The Kathu Pan record registers a relatively moist phase occurring between 4.8 ka and 2.5 ka cal BP. Local environmental conditions at Kathu Pan shift gradually beginning around the terminal Northgrippian ~4.8 ka cal BP. Kathu Pan reaches maximum moisture availability with marsh-like conditions signaled by increased organic content, dominance of Cyperaceae pollen, presence of freshwater fungi, and δ13C values consistent with local C3 vegetation, around the inception of the Meghalayan Stage, although due to uncertainties in the age-depth model these changes may have taken place 1–2 centuries on either side of the formal date for the onset of the Meghalayan at 4.2 ka cal BP. This interval also corresponds with the highest charcoal concentrations, indicating the importance of adequate moisture conditions to support the growth of biomass which eventually becomes a fuel source. The moist phase lasts ca. 2000 years until a hypothesized shift to arid conditions occurs c. 2.5 ka cal BP leading to a change in local hydroclimate that may have terminated the accumulation of organic-bearing sediments.

In Australia, the proportion of forest area that burns in a typical fire season is less than for other vegetation types. However, the 2019–2020 austral spring-summer was an exception, with over four times the previous maximum area burnt in southeast Australian temperate forests. Temperate forest fires have extensive socio-economic, human health, greenhouse gas emissions, and biodiversity impacts due to high fire intensities. A robust model that identifies driving factors of forest fires and relates impact thresholds to fire activity at regional scales would help land managers and fire-fighting agencies prepare for potentially hazardous fire in Australia. Here, we developed a machine-learning diagnostic model to quantify nonlinear relationships between monthly burnt area and biophysical factors in southeast Australian forests for 2001–2020 on a 0.25° grid based on several biophysical parameters, notably fire weather and vegetation productivity. Our model explained over 80% of the variation in the burnt area. We identified that burnt area dynamics in southeast Australian forest were primarily controlled by extreme fire weather, which mainly linked to fluctuations in the Southern Annular Mode (SAM) and Indian Ocean Dipole (IOD), with a relatively smaller contribution from the central Pacific El Nino Southern Oscillation (ENSO). Our fire diagnostic model and the non-linear relationships between burnt area and environmental covariates can provide useful guidance to decision-makers who manage preparations for an upcoming fire season, and model developers working on improved early warning systems for forest fires.

The Late Pliocene–Early Pleistocene is an important transitional period in the Cenozoic evolution of global climate and environment. Previously, we demonstrated the occurrence of distinct cycles in vegetation and climate in the Nihewan Basin, during 2.89–1.78 Ma. However, the specific cycles and their forcing mechanisms were not studied more in-depth. Here we present the results of wavelet and spectral analyses of pollen percentages (Picea, Pinus, xerophytic taxa and broadleaved trees), macro-charcoal concentration, clay % and sand %, and magnetic susceptibility of 340 samples from the NHA drill core in the Nihewan Basin, during 2.89–1.78 Ma. The results reveal dominant ~20-kyr and ~40-kyr cyclicities: the pollen percentages of Pinus and broadleaved trees, magnetic susceptibility, and clay %, indicating a warm and humid climate, are more significantly influenced by ~20-kyr; in contrast, the percentages of Picea and xerophytic taxa, macro-charcoal concentration, and sand %, associated with a cold and dry climate, are mainly influenced by ~40-kyr. The ~20-kyr and ~40-kyr cycles corresponding to the dominant cycles of the East Asian summer monsoon and winter monsoon, which are respectively driven by Earth orbital precession and tilt, indicating that vegetation and climate change in the Nihewan Basin during 2.89–1.78 Ma was forced by a combination of low- and high-latitude processes. Otherwise, most of the proxy indexes also show a pronounced ~100-kyr cycle, which may be a response to changes in Northern Hemisphere ice sheets, emphasizing the importance of high-latitude forcing of vegetation and climate change in the Nihewan Basin.

The goal of the research is to determine the effect of pretreated poultry manure and irrigation on the yield and quality of potatoes (Solanum tuberosum) grown in fields located on the southern steppe of the Republic of Bashkortostan. Field experiments were repeated every three years. During vegetation, potato leaves and tubers were studied at the full blossom, leaves’ decay, and potato harvest. The results showed that applying pretreated poultry manure at the rate of 120 t/ha favored higher tuber weight both on the rainfed and irrigated plots (from 0.23 to 0.82 kg/plant and from 0.24 to 1.02 kg/plant, respectively). On the rainfed and irrigated plots where poultry mature was not applied (control fields) the tubers’ weight ranged from 0.08 to 0.31 kg/plant and from 0.16 to 0.50 kg/plant, respectively. Upon application of 40 t/ha of manure, under irrigation, the highest marketable value of tubers was 78%. On the rainfed plots the same value was 72% when applying poultry manure at a dose of 120 t/ha. Soil moisture monitoring showed that the potatoes did not get adequate water during the growing season. When the soil moisture on irrigated plots was 70% less than its minimum water capacity, potato plantings were watered.

More frequent extreme rainfall events associated with global climate change cause greater challenges for soil conservation. Severe erosion occurs on many unpaved roads since these structures create important water flow paths during heavy storms. The present research aimed to investigate the intensity and influencing factors of unpaved road erosion under varied land use and management conditions (sloping cropland, terraced cropland, forest & grass). The erosion occurred in the watersheds contributing runoff water to roads after the greatest rainfall event recorded in the mountain area of northern China caused by Typhon Lekima. The research was conducted in an agricultural-forest-dominated watershed based on field investigation and UAV-based image analysis. A road erosion level classification standard was given according to the occurrence of rills, ephemeral gullies, and gullies. Significant erosion happened on 67% of the unpaved roads; 42% of them suffered moderate to severe erosion in which ephemeral gullies or gullies developed. The average erosion amount from these roads was 2280.75 t ha-1 and was significantly influenced by the watershed land use type and management. The dominant factor governing unpaved road erosion associated with terraced cropland was vegetation coverage on roads. Drainage area was the most important factor for road erosion in sloping cropland and forest & grass land, and road gradient was also a critical factor. Terraces, and forest & grass in drainage areas significantly reduced unpaved road erosion by 85% and, 47%, respectively, compared to sloping cropland. More integrated measures should be used to prevent unpaved road erosion. The results of this research can be applied to road protection against erosion in heavy storms.

Aeolian sandy lands are widespread and desertification is recognized as one of the main environmental issues in the Yarlung Zangbo River valley, southern Tibetan plateau. The surface microtopographic variations induced by the near soil surface characteristics of plant communities are important compositions of land surface roughness, which likely influence wind erosion. This study was conducted to quantify the effects of typical vegetation restoration on land surface roughness on the aeolian sandy lands, and to identify the main influencing factors of land surface roughness in the Yarlung Zangbo River valley. Two bare sandy lands (as controls) and eight vegetated sandy lands with different restoration communities and ages were selected, and land surface roughness (LSR), as represented by surface microtopographic variations in this study, was measured by photogrammetric surveys. The results showed that LSR significantly increased by 7.9–16.8 times after vegetation restoration on the aeolian sandy lands, and varied among different restoration communities and ages. The mostly restored communities of Sophora moorcroftiana and Populus L. had greater LSR as compared to Artemisia wellbyi and Hedysarum scoparium. With succession from 6 to over 30 years, LSR gradually increased in the Sophora moorcroftiana restored sandy lands, but decreased in the Populus L. restored sandy lands. The variations of LSR were mainly attributed to the differences in near soil surface characteristics of vegetation (plant stem diameter and coverage, and plant residue density) and biological soil crusts (coverage and thickness). Mixed plantation of Populus L. and Sophora moorcroftiana was considered as the best restoration communities because of their effectiveness in increasing land surface roughness on the aeolian sandy lands in the Yarlung Zangbo River valley. The results would facilitate the understanding of the benefits of vegetation restoration in controlling wind erosion on the aeolian sandy lands.

As an important region of desertification in China, the Qinghai-Tibetan Plateau (QTP) has attracted great attention. However, the study of land desertification history at the millennia-scale on the interior plateau is grossly inadequate. In a severely and rapidly desertifying area in the Beiluhe Basin on the interior QTP, grain-size distributions, sand particle morphologies, and 7 available optically stimulated luminescence (OSL) ages of sand sediment from two fixed aeolian dunes were obtained by several laboratory tests. Combining these results with plateau paleoclimate and contemporary aeolian sand activities in several adjacent regions, two phases of evident enhanced aeolian sand accumulation corresponding to desert expansion over the past 1500 years in the study region were identified. The first enhanced phase (850–700 a B.P.) might have been closely related to suitable trapping of denser vegetation cover and degradation of permafrost on the QTP as a consequence of warm and wet climates. Reactivation of local older sediments caused by cold and dry climates might have been responsible for the second enhanced phase (1400–1200 a B.P.). Permafrost plays an important role in aeolian sand accumulation and desertification on the QTP. However, expansion (or degradation) of permafrost has not always prevented (or promoted) aeolian desertification development on the QTP since the Last Glaciation Maximum (LGM, 21–14–12 ka B.P.). The effects of permafrost on aeolian desertification are governed by numerous factors such as preceding and current climate conditions, locations of permafrost and aeolian sand activity, and trap conditions due to vegetation and topography.

Overdependence on exotic plant species constitutes a major setback for the consumption of wild fruits and vegetables among South Africans. The country is not spared from the adverse effects of climate change which play a substantial role in altering the ecosystem and have a ripple effect on food security. Wild fruits and vegetables have been identified to be underutilized despite the country's struggle in nourishing its population. This paper reviewed the impacts of climate change on the phenology, physiology, and economic benefits of wild fruits and vegetables in South Africa. Furthermore, spatial-based data was used to evaluate the possible productivity of wild fruits and vegetables through land use/land cover (LULC) assessment. The result showed that South Africa had varied vegetation and land cover dynamics. For example, Northern Cape and Western Cape Provinces are dominated by shrubland and barren land, thus unsuitable for fruit and vegetable production. In contrast, Limpopo, North-West, Mpumalanga, Gauteng, Free State, some parts of KwaZulu-Natal and Eastern Cape Provinces are covered with grassland and cultivated areas which made them good for vegetable farming and potential ground for wild fruit and vegetable cultivation. Thus, there is a need to develop cultivation strategies for edible wild fruits and vegetables with known nutritional characteristics to expand knowledge about nutritional benefits and options in utilizing the wild species. This will boost the country's economy, help to improve diet, and can play a crucial role in food security.

Hillslope hydrology is a very important part of research based on watershed hydrology. In this study, we focus on water flow over a soil surface with vegetation in a hydrographic basin. We introduce a partial-differential-equation model based on the general principles of fluid mechanics where the unknowns are the depth and velocity of water. The effect of vegetation on the dynamics of water is explained in terms of porosity (a quantity that is related to the density of vegetation) that is a function defined over the hydrological basin. Using a Finite Volume scheme for discretization in space, we introduce an ordinary-differential-equation system that constitutes the base of the discrete model that we are working with. We discuss and investigate several properties of this model that have a physical relevance. Finally, we perform different quantitative validation tests by comparing numerical results with exact solutions or with laboratory-measured data. We also consider some qualitative validation tests by numerically simulating the flow on a theoretical vegetated soil and on a real hydrographic basin.

Predictions of how vegetation responds to spatial and temporal differences in climate rely on established links with plant functional traits and vegetation types that can be encoded into Dynamic Global Vegetation Models. Individual traits have been linked to climate at species level and at community level within regions. However, a recent global assessment of aggregated community level traits found unexpectedly weak links with macroclimate, bringing into question broadscale trait–climate associations and implicating local-scale environmental differences in the filtering of communities. To further evaluate patterns in light of these somewhat contradictory results, we quantified the power of macro-environmental variables to explain aggregated plant community traits, taking advantage of new trait data for leaf area, plant height and seed mass combined with a national survey that records cover-abundance using consistent methods for a large number of plots across Australia. In contrast to the global study, we found that abundance-weighted community mean and variance of leaf area and maximum height were correlated with macroclimate. Height and leaf area were highest in wet (especially warm, wet) environments, with actual evapotranspiration explaining 30% of variation in leaf area and 26% in maximum height. Seed mass was weakly related to environment, with no variable explaining more than 5% of variance. Considering all three traits together in a redundancy analysis, the complete set of environmental variables explained 43% of variation in site-mean traits and 29% of within-site trait variance. While significant trait variation remains unexplained, the trait–environment relationships reported here suggest climatically-driven filtering plays a strong role in assembling these vegetation communities. Regional assessments using standardised species abundances can therefore be used to predict aspects of vegetation function. Our quantification of plant community trait patterns along macroclimatic gradients at continental scale thereby contributes a much-needed functional basis for Australian vegetation.

Farmland bird populations are in a deep crisis across Europe. Agri-environment schemes (AES) were implemented by the European Union to stop and reverse the general decline of biodiversity in agricultural landscapes. In Germany, flower strips are one of the most common AES. Establishing high-quality perennial wildflower strips (WFS) with species-rich native forb mixtures from regional seed propagation is a recent approach, for which the effectiveness for birds has not yet been sufficiently studied. We surveyed breeding birds and vegetation on 40 arable fields with WFS (20 with single and 20 with aggregated WFS) and 20 arable fields lacking WFS as controls across Saxony-Anhalt (Germany). Additionally, vegetation composition, WFS quantity and landscape structure (e.g. distance to nearest woody element) were considered in our analyses. All WFS were established with species-rich native seed mixtures (30 forbs) in agricultural practice as AES. Arable fields with WFS had a higher species richness and territory density of birds than controls, confirming the effectiveness of this AES. A forb-rich vegetation was the main driver promoting birds. Flower strip quantity at the landscape level had positive effects only on bird densities, but also single WFS achieved benefits. A short distance from WFS to woody elements increased total bird species richness. However, the density of farmland birds, which are target species of these AES, were negatively affected by the proximity and proportion of woody elements in the vicinity. The effect of the proportion of non-intensively used open habitats and overall habitat richness was unexpectedly low in the otherwise intensively farmed landscape. Species-rich perennial WFS significantly promoted breeding birds. Successful establishment of WFS, resulting in high-quality habitats, a high flower strip quantity as well as implementation in open landscapes were shown to maximise the effectiveness for restoring declining and AES target farmland birds.

Understanding the interacting role of climate and habitat in shaping wildlife population dynamics can help to reveal synergistic pathways that drive population resilience or decline across variable and changing environments. Moose (Alces alces) is a pan-boreal herbivore experiencing population declines across large portions of North America; however, the species has shown variable response to climate across its distribution. We investigated moose demographic response to climate and evaluated the interacting role of habitat across 36 years and along a biogeographic gradient in Ontario, Canada that has experienced decadal changes to climate and habitat quality. Moose density exhibited a nonlinear trend that initially increased and then decreased over the study timeframe and was negatively affected by regional and local patterns of winter severity and later frost onset. Recruitment exhibited a monotonic decline and was positively affected by spring heat and deciduous forest cover, while also exhibiting density-dependent effects. The negative response of moose density to winter severity was reduced in Wildlife Management Units (WMUs) with higher proportions of dense canopy cover, supporting expectations that this habitat type improves moose winter mobility and predator avoidance. The negative effect of later frost onset was greater in WMUs with more regenerating forest, and both variables are associated with higher exposure to parasites and predators. Further, density-dependent effects on recruitment were suppressed by warmer springs that support vegetation productivity and in WMUs with higher proportions of dense canopy cover that can provide concealment from predators. Our study illustrates the important role habitat conditions can have to mitigate, or exacerbate, climate-change effects for a wide-spread herbivore occupying variable environments by potentially altering pathways relevant to energetic balance, predation, and parasite transmission. In this system, moose occupying sparse or regenerating forests are more susceptible to adverse climatic effects and should be managed accordingly.

Palaeoecological evidence is compared with the existing archaeological record to understand how changing human activity, over the past two millennia, impacted fire regimes and vegetation dynamics in the Drakensberg Mountains, South Africa. Sediment cores from two wetland sites in the Cathedral Peak area of the northern Drakensberg, KwaZulu-Natal are dated using accelerator mass spectrometry to chronologically support biological proxy data. Fossil pollen analysis is used to detect changes in vegetation composition, and macroscopic charcoal to reconstruct changing fire regimes. Charcoal accumulation rates (CHAR) are used as a proxy for burned biomass, and charcoal width-to-length ratio (W/L) as a proxy for dominant fuel type, whether grassy or woody. Results indicate an increase in CHAR, coincident with the appearance of cereal-type grasses (>40 μm) c. 550 cal BP, suggesting a change in fire regimes associated with the arrival of early agropastoralists. A notable decline in charcoal W/L at this time indicates a shift towards a more grassy fuel type. This is consistent with a seasonal shift in the timing of ignitions from high intensity late season lightning fires to low intensity early season anthropogenic fires. The latter are less damaging to woody vegetation explaining an overall shift to a more grassy fuel type. Large scale ecosystem change is evident in the colonial period, including decreased forest pollen taxa such as Podocarpus, which may be linked to colonial period logging. The increased dominance of Pteridium spores documents the invasion trajectory of bracken fern into montane grasslands in the area, which is attributed to ecosystem disturbance in the form of colonial fire suppression. The subalpine wetland clearly documents woody encroachment of the surrounding open grassland landscape during the agropastoral and subsequent colonial periods. By contrast, at the montane wetland site, these trends appear to be overprinted by local forest dynamics and recent deforestation, likely an elevation effect. Palaeoecological evidence demonstrates how changes in fire regimes and vegetation composition in the northern Drakensberg are closely tied to human activity over the past two millennia.

There is growing interest in aligning the wildlife conservation and restoration agenda with climate change mitigation goals. However, the presence of large herbivores tends to reduce aboveground biomass in some open-canopy ecosystems, leading to the possibility that large herbivore restoration may negatively influence ecosystem carbon storage. Belowground carbon storage is often ignored in these systems, despite the wide recognition of soils as the largest actively-cycling terrestrial carbon pool. Here, we suggest a shift away from a main focus on vegetation carbon stocks, towards inclusion of whole ecosystem carbon persistence, in future assessments of large herbivore effects on long-term carbon storage. Failure to do so may lead to counterproductive biodiversity and climate impacts of land management actions.

Transportation infrastructure has bought many blessings for human civilization, although its negative influences, especially on a forested landscape should be heeded with prime concerns. In this study, we studied, how railway track perforating through Lawachara National Park affecting the nearby vegetation alpha (α) and beta (β) diversity and composition and soil properties, and whether the effects are active until a certain distance into the forest interior. Total 32 plots in 8 transect lines perpendicular to the railway are laid with 4 plots at 10 m, 40 m, 70 m and 100 m distances. Tree and tree regeneration α and β-diversity and composition, and soil organic matter and pH were assessed at each of these plots. Our results showed that, soil organic matter and pH, as well as α-diversity indices were significantly (P .05) with distances. High amount of organic matter in outermost plots was maybe due to the decomposition of litterfall and debris where increased pH value was due to presence of high amount of calcareous substances and plant residue. As the α-diversity of plant decreased with increasing distance from the railway track and in most cases the value decreased until 70 m distance, indicated that the influence of the railway tracks maybe prominent up to 70 m. So, to minimize this effect of vegetation structure proper steps such as careful planning in road building, afforestation using the native species and evaluation of the necessity of infrastructure and possible alternatives to it should be assessed.

Regional as well as global cropland database at a high spatial resolution like 10 m is not available. This study aims to integrate the Sentinel-1 synthetic aperture radar (SAR) data and Sentinel-2 optical data in a more robust way to map the croplands at 10 m spatial resolution. It also examines the effectiveness of different derived products from the SAR and multispectral data. The VH and VV polarizations of the SAR data were used to generate the 80 textural parameters at four different kernel sizes. The multispectral bands of the optical data were used to create nine different spectral indices. The SAR and optical data were classified separately and integrated with the other derived products, using the random forest classifier, to identify the most potential way to use the two datasets for LULC classification. The classification accuracy was the least when only the Sentinel 1 data was used, with an overall accuracy of 59.48% and a kappa value of 0.51. The best accuracy (97.94% overall accuracy and 0.98 kappa value) was achieved by combining the Sentinel 1 and 2 data and their optimal textures and spectral indices. Overall, this study suggests the suitability of the SAR data along with optical data to map the croplands with higher accuracy.

Urban lakes are environments prone to severe environmental deterioration if an effective management policy is not carried out by local governments. However, management aimed only at facilitating access and recreation for citizens can negatively affect the environmental health of these ecosystems since the pristine ecosystem structure is not recovered. In this paper we present early results of a governmental restoration program based on pond cleaning and native vegetation recovery at an artificial lake of the city of Avellaneda (Saladita Norte Reserve), part of the Metropolitan Area of Buenos Aires, one of the largest urban areas with the highest concentrations of inhabitants of the world. We used odonates as indicators because of their quick response to changes in environmental quality. Besides, we tested if the NDVI can be used as a surrogate to monitor changes in dragonfly diversity in managed areas. Since the intervention was carried out during the winter and there were no previous data on the richness or diversity of odonates, we analyzed their response to the intervention comparing it with a lake of similar origin and characteristics but with a different use and management (Saladita Sur Reserve). We recorded in Saladita Norte 81% of the regional diversity, including three newly recorded species, while the lake Saladita Sur, only amounted to 21% of the regional diversity. The NDVI did not reflect the observed changes in the structural complexity of the vegetation and therefore could not be used as a surrogate. These early results indicate that management practices such as the increase of native vegetation on the banks (especially in grassland areas), keeping a diverse floating vegetation and the cleaning and removal of wastes from the water, promote a significant and rapid increase in the levels of biodiversity.

Quantifying the grass biomass content of rangelands is potentially useful to rangeland managers. This study assessed the potential of image-derived vegetation indices to assess in-situ spatial variations in grass aboveground biomass (AGB). Sampling was conducted at the peak growth stage, at widely distributed sampling sites whose grass cover homogeneity was wider than 20 m. Up to three AGB samples per site were collected, in 1 m quadrats. Dry biomass weights were determined and averaged per site. Rainy season Sentinel-2 MSI images of the rangeland that corresponded with the fieldwork dates were obtained. Atmospheric correction of the images was performed using the Sen2Cor algorithm, which yielded 20 m resolution visible (vis), red edge (RE), near infrared (NIR), and short wave infrared (SWIR) bands. Seven biomass-sensitive vegetation indices that utilised Sentinel-2 MSI vis-RE-NIR-SWIR spectral ranges were then tested using the images, to determine which correlated best with the field-derived AGB. They were the Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), Soil Adjusted Vegetation Index (SAVI), Normalized Difference Red Edge index (NDRE), Red Edge Inflection Point (REIP), Aerosol Free Vegetation Index (AFRI2.1μm), and Normalized Difference Water Index (NDWI). In decreasing order of magnitude, the EVI, SAVI, NDVI, AFRI2.1μm, and NDWI had statistically significant correlations with AGB (p ≤ 0.05). The discontinuous canopies but high biomass of tall-grass species weakened the correlations. The EVI model of AGB was then used for depicting rangeland-scale, location-context spatial variations in AGB. Pixels with woody vegetation cover ≥50% were excluded using a binary mask that was developed through sub-pixel classification of a grass-senescence period Sentinel-2 MSI image. A statistically significant linear relationship (F = 21.192, p = 0.000) between EVI-predicted and actual AGB was established (r = 0.765, p

New compound-specific isotope analyses of a sediment core from Laguna Los Mangos in southern Pacific Costa Rica improves understanding of late-Holocene precipitation change in a region with limited paleoprecipitation records that is vulnerable to future climate change. We established paleoprecipitation and paleovegetation records from compound-specific stable hydrogen and carbon isotopic compositions of terrestrially-derived n-alkanes (δ2Halkane and δ13Calkane) to assess paleohydrologic variability and potential linkages to paleoecological change and human activity as revealed by prior analyses of the Los Mangos core. The δ2Halkane values were corrected for isotopic fractionation using pollen counts from the same core. The Los Mangos record extends to 4200 cal yr BP and small increases in δ13C values of C29, +0.6‰, and C31 alkanes, +0.3‰, (δ13CC29, 31) indicate a slight increase in C4 vegetation after initial introduction of maize agriculture to the watershed at ca. 3360 cal yr BP. This slight increase in C4 vegetation is followed by the largest positive carbon isotope excursions in the record, as compared to record averages (δ13CC29 = +3.2‰, δ13CC31 = +5.0‰). Paleohydrologic variability likely influenced vegetation and human activity at Los Mangos. Lake desiccation during the late-Terminal Classic Drought (TCD) resulted in a sedimentary hiatus in the Los Mangos record from ca. 950 to 450 cal yr BP. Positive excursions in comparison to record averages occur for both δ2HC29 and δ2HC31 proxies (δ2HC29 = +25.3 to +13.4‰ and δ2HC31 = +6.5‰) during the middle Little Ice Age (LIA) and indicate drier than average conditions, but there is no evidence of desiccation during this period. Thus, drought conditions during the LIA were apparently not as severe at Los Mangos as during the TCD, possibly because of differing forcing mechanisms for LIA climate that originated, or were more clearly expressed, in the Atlantic basin.

Coverage of living (green) vegetation influences rangeland processes and biodiversity but remains a challenge to quantify at small spatial grain. We describe a technique for rapid airborne (unmanned aerial vehicle) measurements of continuous spatial coverage of living vegetation at a resolution (spatial grain) of 8 cm ground sampling distance. We then applied this technique at the pasture (paddock) scale (tens of hectares) in two contrasting grassland ecosystems (semiarid shortgrass steppe in northeastern Colorado, United States and mesic grassland in central Texas, United States) to determine effects of locally relevant grazing treatments on spatial variability and dependence (pattern) in fractional coverage of green vegetation (fractional vegetation cover; FVC). Site-specific regression models developed using reflectance in visible and near-infrared wavebands explained 90% and 89% of variance in FVC for semiarid and mesic grassland, respectively. Mean FVC was similar among shortgrass steppe pastures differing in grazing treatment (light or heavy grazing by cattle, moderate cattle grazing with prairie dogs present). In contrast, FVC was lower with rotational compared with continuous, year-long grazing in the mesic grassland. Heavy grazing in shortgrass steppe and rotational grazing in mesic grassland increased the spatial uniformity in FVC by reducing spatial variability and increasing spatial dependence in FVC, the latter by increasing the similarity in FVC values among spatially separated patches. Unmanned aerial vehicle−enabled remote sensing provides for FVC at sufficiently small spatial grain to characterize spatial variation in FVC at the pasture scale. Results can be used to evaluate the effectiveness of management actions intended to alter spatial variation in FVC to achieve conservation or diversity objectives. Enhanced capacity to monitor FVC at small spatial grain promotes adaptive management of grasslands.

Ecological niche models (ENMs) are often used to investigate how climatic variables from known occurrence records can estimate potential species range distribution. Although climate-based ENMs provide critical baseline information, the inclusion of non-climatic predictors related to vegetation cover might generate more realistic scenarios. This assumption is particularly relevant for species with life-history traits related to forest habitats and sensitive to habitat loss and fragmentation. Here, we developed ENMs for 36 Atlantic Forest endemic birds considering two sets of predictor variables: (i) climatic variables only and (ii) climatic variables combined with the percentage of remaining native vegetation. We hypothesized that the inclusion of native vegetation data would decrease the potential range distribution of forest-dependent species by limiting their occurrence in regions harboring small areas of native vegetation habitats, despite otherwise favorable climatic conditions. We also expected that habitat restriction in the climate–vegetation models would be more pronounced for highly forest-dependent birds. The inclusion of vegetation data in the modeling procedures restricted the final distribution ranges of 22 out of 36 modeled species, while the 14 remaining presented an expansion of their ranges. We observed that species with high and medium forest dependency showed higher restriction in range size predictions between predictor sets than species with low forest dependency, which showed no alteration or range expansion. Overall, our results suggest that ENMs based on climatic and landscape variables may be a useful tool for conservationists to better understand the dynamic of bird species distributions in threatened and highly fragmented regions such as the Atlantic Forest hotspot.

Abiotic environmental factors have a major impact on the distribution and performance of plant species. For this purpose, regarding the importance of Vicia variabilis in forage production and the possibility of using it in the improvement and reclamation of oak forest understory, this study aimed to investigate the effect of soil variables and topography on the response of this species using generalized additive models in the west of Iran. The results showed that the response pattern of V. variabilis along the gradient of clay, silt, and soil saturation moisture followed the monotonic increase model. Conversely, the response of this species along the gradient of sand percentage, bare soil percentage, and content of sulfate salts in the soil followed the monotonic decrease model. The species response pattern along the gradients of electrical conductivity, lime percentage, pH of soil, soil sodium ion, phosphorus, altitude, slope, stone and gravel percentage, and canopy cover percentage of the forest overstorey followed a unimodal model, and its optimal growth limit for these factors was 0.85 dsm–1, 5.10%, 7.26, 0.38 meql–1, 35 ppm, 1 650 m, 31%, 7%, and 25%, respectively. The results of phenological studies on V. variabilis during 2018 to 2020 showed that late June/early July was the most suitable time for livestock use of this species, and the best time to collect the seeds was mid-July to the early August. Regarding the response of this plant to the gradient of studied environmental factors, it is recommended to pay attention to its habitat characteristics and ecological requirements in improvement programs on oak forests understory vegetation.

Forested buffer zones with varying width have been suggested as the most promising approach for protecting boreal riparian biodiversity, reducing erosion, and minimizing nutrient leaching from managed forestry areas. Yet, less optimal fixed-width approach is still largely used, likely because of its simple design and implementation. We examined the efficiency of varying-width buffer zones based on depth-to-water (DTW) index in protecting stream riparian plant communities. We further compared the economic costs of DTW-based buffer to commonly used 5, 10 and 15 m fixed-width buffers. We also included an additional buffer based on a combination of DTW and erosion risk (Revised Universal Soil Loss Equation, RUSLE) into these comparisons to see the extent and cost of a buffer that should maximize the protection of the linked aquatic environment. Plant species richness increased with increasing soil moisture and species preferring moist conditions, nutrient-rich soils and high pH were clearly more abundant adjacent to stream in areas with high predicted soil moisture than in dry areas. Differences in species richness were paralleled by differences in community composition and higher beta diversity of plant communities in wet than in dry riparian areas. There were also several indicator species typical for moist and nutrient-rich soils for wet riparian areas. Riparian buffer zones based on DTW were on average larger than 15 m wide fixed-width buffers. However, the cost for DTW-based buffer was lower than for fixed-width buffer zones when the cost was normalized by area. Simulated selective cutting decreased the costs, but cutting possibilities were variable among streams and depended on the characteristics of forest stands. Our results thus suggest a high potential of DTW in predicting wet areas and variable-width buffer zones based on these areas in the protection of riparian biodiversity and stream ecosystems.

International audience; The current study tries a new approach to simulating interactions between waves and seagrass through Smoothed Particle Hydrodynamics (SPH). In this model, the plants are defined as a solid that respects Hooke's law, and are assumed to have direct interaction with the fluid. Given the characteristics of the SPH method, especially in terms of computational time, the dimensions of the simulations were limited. The first goal of the current study was to optimize the approach to avoid reaching certain limits such as the rupture of the simulated plant. Plant movements under waves and/or currents have been studied by several authors in various in-situ, physical, and numerical experiments concerning various vegetation species, thus proving that plant movements can be successfully reproduced by SPH 2D/3D. Manning's roughness coefficient, n, was calculated to confirm that the results were in accordance with what had been measured in flume studies. Even though there is still room for improvement, it is shown that this method can be used to estimate Manning's coefficient for coastal vegetation (seagrass and saltmarsh vegetation) and to greatly improve the modeling and forecasting of coastal erosion and storm surge risks by including the effects of vegetation in integrated models.

In permafrost peatlands, the degradation of permafrost soil can raise soil temperature and alter moisture conditions, which increases the rate of loss of soil organic carbon (SOC). Here we selected three typical permafrost types that have very different active layer thicknesses but with soil originating from the same vegetation and which exist under comparable climatic conditions in the Da Xing’an mountain range: continuous permafrost, island permafrost, and island melting permafrost. To quantify the relative importance of control elements on SOC stabilization in these different permafrost types, we used correlation analysis to assess the relationship between organic carbon, physical and chemical properties and microorganisms, and explored the contribution of these factors to the accumulation of organic carbon. This study shows that the interaction between clay or silt, iron oxides and microorganisms have an important influence on the stability of organic carbon in permafrost peatlands.

The Presque Isle Peninsula is a compound barrier-spit system perched atop a recessional moraine along Lake Erie’s southeastern coast. Its distal terminus, Gull Point, has grown to an extent of around 0.6 km2 since the early 1900s, promoted by beach nourishment along the peninsula proper and later influenced by a change in local hydrodynamic regime following breakwater installation near the attachment point. This coastal setting has set the stage for an analysis of ridge landform- and vegetation-succession dynamics using historical aerial images, a series of high-resolution LiDAR datasets, transect/quadrat surveys of vegetation, and increment core dates of tree cohorts on dune ridges separated by swales and lagoons. The general evolutionary model is one of punctuated landform growth to the east by lateral accretion, interspersed with erosional events and ridge recurving towards the backbarrier. Eastern cottonwood (Populus deltoides), with its minimally provisioned wind- and water-dispersed seeds, colonizes the margins of newly deposited sand ridges as discrete cohorts, and dominates the tree stratum of Gull Point. These cohorts are increasingly mature moving from distal to proximal zones, and consistently reflect the temporal sequence of ridge morphology. Vegetation communities, representing a primary successional chronosequence, are delineated into four phases extending back to the 1950s, which are roughly demarcated by erosional ridgelines of topographic prominence, revealing a tight coupling of lake-level trends, geomorphology, and vegetation dynamics. This provides coastal researchers with a means of understanding landform-age relationships across structurally complex strand areas for which age-relationships cannot be ascertained by aerial photographic records alone.

This study was conducted during 2018–19 to evaluate the floristic composition and ecological characteristics of vegetation of Pashat valley, Bajaur. Floristic list of the valley contains 385 species distributed in 291 genera and 102 families. The dicotyledons having 83 families with 311 species and monocotyledons with 12 families contains 61 species. Pteridophytes having 05 families with 11 species and gymnosperm with a single family of two species. The leading family was Asteraceae with 42 species (10.90%) followed by Poaceae with 39 species (10.10%), Papilionaceae (Fabaceae) with 24 species (6.23%), Lamiaceae with 20 species (5. 19%) and Rosaceae with 15 species (3.90%). Therophytes 180 species (46.80%), hemicryptophytes 53 species (13.80%), nanophanerophytes 51 species (13.20%) and geophytes 35 species (9.09%) were the dominant life form groups. Leaf size class was dominated by microphylls (138 species, 35.84%) followed by nanophylls (124 species, 32.21%) and mesophylls (89 species, 23.12%). Habit wise the vegetation was mostly herbs (289 species) followed by shrubs (54 species), trees (38 species) and lianas (4 species). According to flowering phenology, most plants (62.30%) bloomed in spring followed by in summer (34%), in autumn (1.82%), in the whole year (1.30%) and in winter (0.52%). Based on chorological affinities, most of the species were bioregional in distribution (170 species, 44.15%) followed by mono-regional (157 species, 40.78%), pluri-regional (43 species, 11.17%) and cosmopolitan (15 species, 3.89%). The ecological characteristics like life form and leaf size spectra of the vegetation have a strong correlation with the prevailing environmental conditions such as altitude, slope, precipitation and temperature.

Central Yunnan Province is the political, economic, cultural, and transportation hub of Yunnan Province, China. Climate change has resulted in increased seasonality of global averaged precipitation, temperature, runoff, and evapotranspiration, thereby exacerbating extreme events such as drought and soil erosion. The simulation and mapping of drought and soil erosion within Central Yunnan Province is important for achieving sustainable development. This study constructed a comprehensive drought monitoring model and a soil erosion model based on multiple sources of remote sensing data, considering numerous drought and soil erosion factors. The temporal and spatial characteristics of dry-season drought and soil erosion for 2010 to 2018 in Central Yunnan Province were explored, and the extents of soil erosion in different parts of Central Yunnan Province were quantified using the soil erosion intensity index. The results showed that: (1) The multi-year average percentage dry-season drought coverage and average drought frequency were 33.98% and 18.33 months, respectively. Although drought frequency was higher in areas with high drought intensity, dry-season drought showed a long-term weakening trend. (2) Over the study period, the multi-year average soil erosion of Central Yunnan Province was 1,551.45 t km−2·yr−1. Soil erosion showed an initial overall increasing trend, followed by a decreasing trend, dominated by micro erosion, mild erosion, and moderate erosion, whereas the mountains and valleys in north and southwest parts of Central Yunnan Province experienced severe erosion. Vegetation coverage and slope were identified as the main factors driving soil erosion. (3) The soil erosion intensity index was a good indicator of soil erosion severity across different spatial scales and different drought grades. The soil erosion intensity index showed a positive relationship with drought grade. The correlation coefficients between soil erosion intensity and drought frequency and between soil erosion intensity and drought intensity were 0.2623 and −0.2679, respectively. This study demonstrated that drought affects soil erosion and that water and soil conservation measures such as afforestation and vegetation greening are beneficial to mitigating soil erosion and drought in Central Yunnan Province.

Climate instability in the Eemian Interglacial is gaining more and more evidence. One of such oscillations in the Beckentin record is indicated by the disappearance of the Cladocera and changes in macroremains at the beginning of E4a (Corylus phase). They confirm the shallowing of the reservoir, probably caused by climate changes, but not reflected in the palynological record. However, a significant oscillation observed in the first half of the E5 (Carpinus phase), ~5860 years after the boreal forests subsided and ~6290 years after the onset of interglacial forestation, suggests that, although not being an analogue of the OHO (Older Holsteinian Oscillations) in MIS 11c and the 8.2 ka cold event in the Holocene, it is very similar to these oscillations. The Eemian oscillation was noted also in the Bispingen profile in northern Germany, ~6500 years after the interglacial forestation. However, the course of vegetation changes there differs from that in Beckentin. The analysis of macroremains and Cladocera confirms the disappearance of rush and water vegetation in the water reservoir at that time in Beckentin. These results confirm that numerous climatic oscillations could have occurred in the Eemian Interglacial.

Degradation of carrying capacity due to any reason is a serious concern for ecosystem as well as for dynamical system. It is observed in alpine meadow ecosystem that carrying capacity of vegetation reduces due to digging holes, throwing out soils, piling up mounds by plateau pika. In this ecosystem, it is also observed that height of vegetation increases death rate of plateau pika. These two facts when considered with environmental fluctuation make it an interesting topic of discussion in dynamical system. This motivation leads us to a stochastic analysis of a prey–predator model in alpine meadow ecosystem. In this analysis, Gaussian White noise has been introduced to exhibit the influence of environmental fluctuations on prey’s growth rate and predator’s death rate. We have established positivity and boundedness of the system theoretically. Extinction scenario, persistence of the system and global attractivity of solutions are also established. Numerical simulation validates theoretical results. Moreover, the appropriateness of the model in numerical simulation has also been justified with the help of some field experimental data. In discussion section, another approach for formulating the model has also been discussed.