Vegetation Landscape Research Articles

An Evaluation Model of Riparian Landscape: A Case in Rural Qingxi Area, Shanghai

The suburbs around Shanghai have a complex river network and a unique Chinese water-town culture. The riparian landscape in the rural Qingxi area has important regional, ecological, and social significance; it serves as an important part of the local bioclimate, but the existing studies on river vegetation did not pay enough attention to the riparian landscape in the countryside around the metropolis. The goal of this study was to examine a comprehensive evaluation model for the river plant landscape in the countryside surrounding a high-density metropolis such as Shanghai in the face of the national policy of rural revitalization and the low-carbon development problem, and to propose optimization strategies accordingly. Therefore, in this study, we selected 91 rivers in the Qingxi area and investigated their plant communities. According to the characteristics of the riparian landscape and its relationship with the river environment and local bioclimate, we classified the 91 riparian landscapes into four types of quadrats: natural landscape, residential recreation, roadside linear landscape, and agricultural landscape. In addition, based on the 13 indicator layers under the categories of ecological carrying capacity, landscape beauty, and social service, we calculated the comprehensive evaluation value (CEV) and comprehensive evaluation index (CEI) of 91 river quadrants using specific formulas to scientifically evaluate the riparian landscape in the rural Qingxi area of Shanghai. Finally, based on the existing problems summarized through data analysis, the researchers proposed five optimization directions: (1) increasing vegetation diversity, (2) choosing native and culturally representative species, (3) improving waterfront planting design, (4) achieving ecological riverbank construction, and (5) building greenway systems and recreational spaces. This study proposed an innovative evaluation model for the riparian vegetation landscape and tested its feasibility by site survey, which provided new visions for future rural landscape research.

3D Evaluation of fine-scale normalised DSMs in urban settings

Humankind often needs to accurately model, identify and spatially quantify aboveground phenomena on the Earth’s surface for informed decision-making. Height data derived from digital elevation models (DEMs) is often used to achieve this. This study conducted a deterministic assessment of three normalised digital surface models (nDSMs) of different spatial resolutions, namely 2m, 4m and 12m, derived from VHR digital stereo aerial photography, tri-stereo Pléiades imagery and Tandem-X InSAR data, respectively. Covering a predominantly built-up area within a city landscape, the nDSMs were vertically and volumetrically compared to assess their quality and fit-for-use. In each case a consistent systematic evaluation was accomplished against a lidar derived reference surface at matching spatial resolutions (co-registered) using a semi-automated GIS routine. The relative height and volumetric errors were statistically analysed and described, including those computed individually over nine urban land cover/land use (LCLU) classes and several selected large buildings. Higher vertical accuracies were reported across single storey structures and areas with no to little or short vegetation, as apposed to substantially lower accuracies obtained over multi-levelled buildings and tall (dense) woody vegetation. Here significant underestimations of volumes exacerbated by lower spatial resolutions were also observed across each nDSM. Conversely, notable volume overestimations were found over predominantly grass-covered areas in especially the finer-scaled nDSMs. VHR elevation data is recommended to model and quantify aboveground elements spatially in 3D (e.g. buildings, earthworks and woody vegetation) in urban landscapes, but a sensitivity test beforehand remains critical to ensure more reliable outcomes for users and stakeholders alike.

Space-time analysis of the phytocenotic cover of the mining and industrial landscapes of the right-bank forest-steppe

In the proposed article we highlight the peculiarities of the formation of phytocenotic cover within the limits of quarry-dumping complexes of mining and industrial landscapes of Right-Bank Forest-Steppe. It was determined, that the formation of such anthropogenic landscapes depends on the general natural conditions of the territories, production features and the method of mineral extraction. According to the definition of T.A. Rabotnov, within the formed manmade substrates, the emergence of primary succession is possible due to the presence of plant rudiments in the deposits or the ingress of plant diaspores from the outside, which distribution is directly depends on the individual ecotopic conditions within the pits. Therefore, the purpose of our research is to determine the influence of ecotopic conditions on the formation of phytocenotic cover of the mining and industrial landscapes of the Right-Bank Forest-Steppe (on the example of the Andriykovetskyy sand quarry). In order to explore the trends and rates of changes in this area, the dynamics with using photos from different years was determined and landscape maps were created. The Andriykovetskyy sand quarry is a part of the deposits of the Sarmatian layer — the lower geological layer of the upper Miocene of the Neogene period. The investigated territory is characterized by sharp differences in altitude compared to the surrounding agro-ecosystems of related agricultural lands. Breaches, which were caused by mineral extraction processes, are marked by the formed man-made accumulative relief. In the structure of the mining landscape, we highlight the next main areas: the hilly monolithic bottom of the sandpit without vegetation; steep (up to 80°) sandy walls of the quarry without vegetation; hilly loamy-sandy surfaces overgrown with cereal vegetation and various herbs; micro-bumpy surface of sandy loam dumps overgrown with ruderal vegetation; slopes of sandy-loam dumps overgrown with ruderal vegetation, trees and bushes; shaft-shaped embankments overgrown with cereal vegetation and bushes; microbumpy ledges of overburden rocks, overgrown with grass-cereal vegetation and single trees; sloping surfaces overgrown with various herbaceous vegetation; low-lying areas with sufficient moisture, overgrown with moisture-loving vegetation; sandy and loamy areas within the quarry, not occupied by developments. Also, we analyze the changes in vegetation and man-made landscape elements that occurred during the study period: during the three-year observation period, the areas of plant cover within the quarry and the number of species were increased. It was found, that the quarry is characterized by the spread of segetal-ruderal vegetation and the process of synanthropization, which can lead to the loss of typical species diversity

Computer 3D Scene Simulation of Ecological Landscape Layout Planning

There are some problems in traditional 3D landscape construction and virtual display, such as inflexible landscape spatial organization and limitations of virtual garden simulation in reality. Virtual reality, virtual plants and geographic information systems, and other technologies are used. Based on parameterized method in constructing 3D landscape scene, the main elements of the landscape were, respectively, constructed and rendered in 3D model, and a complete 3D landscape scene construction model was formed. OpenGL shader language was used for rendering, improved NSGA-II algorithm was used with the help of bionic logic of the genetic evolution process to achieve landscape land allocation optimization. The experimental result shows: through 3D scene view clipping hierarchical detail model and other techniques, the frame rate of 3D landscape vegetation scene drawing was improved. The interactive 3D scene browsing is realized, and the six-degree-of-freedom omni-directional display of the whole landscape is provided.

High-Resolution Daily Emission Inventory of Biomass Burning in the Amur-Heilong River Basin Based on MODIS Fire Radiative Energy Data

Open biomass burning (OBB) is one of the major factors that influences the regional climate environment and surface vegetation landscape, and it significantly affects the regional carbon cycle process and atmospheric environment. The Amur-Heilong River Basin (ARB) is a fire-prone region in high-latitude boreal forests. In this study, we used fire radiative power (FRP) obtained from a Moderate-resolution Imaging Spectroradiometer (MODIS) to estimate OBB emissions from the ARB and established a long-term series (2003–2020) with a high spatiotemporal resolution and a daily 1 km emissions inventory. The results show that the annual average emissions of CO2, CO, CH4, NMHCs, NOx, NH3, SO2, BC, OC, PM2.5, and PM10 were estimated to be 153.57, 6.16, 0.21, 0.78, 0.28, 0.08, 0.06, 0.04, 0.39, 0.66, and 0.85 Tg/a, respectively. Taking CO2 as an example, grassland fire in the dry season (mainly in April and October) was the largest contributor (87.18 Tg/a), accounting for 56.77% of the total CO2 emissions from the ARB, followed by forest fire prone to occur in April–May (56.53 Tg/a, 36.81%) and crop fire during harvest season (9.86 Tg/a, 6.42%). Among the three countries in the ARB, Russia released the most total CO2 emissions (2227.04 Tg), much higher than those of China (338.41 Tg) and Mongolia (198.83 Tg). The major fire types were crop fires (40.73%) on the Chinese side and grass fires on the Russian (56.67%) and Mongolian (97.56%) sides. Over the past decade, OBB CO2 emissions have trended downward (−0.79 Tg/a) but crop burning has increased significantly (+0.81 Tg/a). Up to 83.7% of crop fires occurred in China (2010–2020), with a concentrated and southward trend. Comparisons with the Global Fire Emission Dataset (GFED4.1s), the Fire INventory from NCAR (FINNv2.2), and the Global Fire Assimilation System (GFASv1.2) showed that our newly established emission inventory was in good agreement with these three datasets in the ARB. However, this multi-year, daily 1 km high-resolution emission inventory has the advantages of detecting more small fire emissions that were overlooked by coarse-grid datasets. The methods described here can be used as an effective means of estimating greenhouse gas and aerosol emissions from biomass combustion.

Vegetation landscape and paleoenvironment evolution recorded at the late Neolithic Zhumucun site, East China

The paddy field ecosystem and diversified plant food resources in the middle and late Liangzhu Culture were revealed at the Zhumucun site. Based on pollen and phytolith records, this paper presents local vegetation landscape of the site: (1) evergreen-deciduous broad-leaved forests dominated by Quercus, Castanopsis, and Ulmus distributed on the nearby hills, (2) terrestrial herbs represented by Poaceae plants tend to expand on the plain, (3) aquatic plants such as Typha, Trapa, Myriophyllum and Euryale ferox grew in rivers and lakes, and (4) plants such as Phragmites australis, Echinochloa, Polygonum lapathifolium, Haloragidaceae, Rumex, Cyperus, Cyperaceae, and Polygonaceae were distributed in and around the wetland. Water activities tended to be intense, and the climate was generally warm and humid with short-term anomalously cold or wet fluctuations. This is in line with the characteristics of environmental changes revealed by regional natural accumulations. In this conditions, local rice ecosystem was recorded with diachronic changes.

Biodiversity in Urban Areas: The Extraordinary Case of Appia Antica Regional Park (Rome, Italy).

The first inventory of the flora of Appia Antica Regional Park (Italy), one of the largest protected urban areas in Europe (4580 ha), its biological, ecological and biogeographical composition, and notes of the vegetation physiognomies and landscape are presented; physical characteristics of the territory (geomorphology, lithotypes, and phytoclimate) are also given. The landscape is defined by an agricultural matrix with natural and seminatural areas as patches, and riparian vegetation communities as corridors. The vegetation physiognomies are represented by types linked to the Mediterranean climate (mixed, Mediterranean, and riparian forests; scrubby, rocky, aquatic, and helophytic vegetation; anthropogenic communities). The floristic list includes 714 taxa (104 families and 403 genera). Therophytes prevail over hemicryptophytes; woody flora comprises about 30% of alien species. As regards chorotypes, together with a considerable number of Mediterranean species, there are many exotic species with wide distribution areas testifying to a long-lasting anthropic impact. Floristic novelties (european, national, and regional levels) for 21 taxa are reported. The extraordinary species diversity discovered (43% of flora of Rome and 20% of regional flora) is linked to the landscape heterogeneity, the characteristics of which are: (1) persistence of residual natural patches, (2) occurrence of quite well-preserved aquatic habitats and humid meadows, (3) a rich anthropogenic flora, (4) an interesting flora of archeological sites, (5) occurrence of species not common in Latium, (6) occurrence of populations of aliens in crops (which cause economic impact), (7) presence of aliens on archeological ruins (which cause economic-social impacts). The extensive set of data provided represents a general base framework for guiding future research efforts and landscape action plans consistent with environmental sustainability.

Numerical simulation of vegetation evolution in compound channels.

The study of vegetation evolution is essential for further understanding of biogeographic feedback and ecological restoration. In this paper, a vegetation evolution model based on velocity threshold (scaled by the average flow velocity of the bare bed) was established to simulate the vegetation evolution process in compound channels. In this model, the effect of vegetation on water flow was generalized as equivalent Manning coefficient, and the velocity field was obtained by solving two-dimensional shallow water equations. The model defined that new vegetation was added in areas where the velocity was less than the velocity threshold, and conversely, vegetation was destroyed in areas where the flow velocity exceeded the velocity threshold. The model was used to explore the effect of velocity threshold, initial vegetation coverage, and relative water depth (the ratio of the flow depth in the floodplain to that over main channel) on final vegetation coverage and longitudinal dispersion coefficient (Ke) in compound channels, and compare the difference of vegetation evolution between rectangular channels and compound channels. Results showed that the velocity threshold played a decisive role in vegetation evolution, and the effect of relative water depth and cross section type on vegetation evolution was only reflected when the velocity threshold was small. The longitudinal dispersion coefficient gradually increased with the expansion of vegetation, and tended to a constant value (Kf) when a stable vegetation landscape was reached. As the relative water depth decreased, the longitudinal dispersion coefficient presented an increasing trend. Regular distribution of initial vegetation patches can produce larger longitudinal dispersion coefficient compared to the cases of random distribution in compound and rectangular channels, and the increasing effect was more significant in compound channels.

Environmental landscape and subsistence strategy of the Shunshanji Culture: A review.

The Shunshanji Culture is the earliest known Neolithic culture in the mid-lower Huai River. In recent years, with new discoveries and deeper studies of the Shunshanji Culture, the concept of the Shunshanji cultural site group has gradually formed. Among them, various types of rice remains have been unearthed in large quantities, which provide key materials for discussing rice farming, rice cultivation and domestication, and related issues in the Huai River Basin. Previous studies have conducted reconstruction of local vegetation landscape and analysis of subsistence strategies on some systematically excavated Shunshanji cultural sites and obtained some new understandings. Integrative research, however, is lacking. In this review, we combine the construction of the local environmental landscape with the settlement landform within the Shunshanji cultural site group and then incorporate it into the regional environmental evolution of the mid-lower Huai River. The consistency and difference in their subsistence were also summarized. In particular, we focus on the relevant clues of the early paddy field cultivation system in the region and perform comparative studies.

Millennial scale erosion and sedimentation investigation in karst watersheds using dating and palynology

The sedimentary sequence deposited in a depression provides good opportunity for karst watershed soil loss reconstruction. Extensive sediment dating and soil loss estimation in karst areas of Southwest China have been carried out in the past few decades. Unfortunately, most studies only revealed soil loss over the last 50–100 years by using 137Cs and/or 210Pb. This study attempts to reconstruct soil erosion in a watershed over the past millennium using sediment dating combined with palynological techniques. In this study, two karst watersheds with different degrees of rocky desertification were selected, and soil profile samples were collected from the depressions to determine pollen taxa, 137Cs and soil organic carbon, and then, the optically stimulated luminescence (OSL) and radiocarbon were used to date the sediments in the two profiles. The results showed that erosion rate characteristics in the Liaojiawodang (LJWD, severe rocky desertification) and Dajutang (DJT, mild rocky desertification) watersheds were markedly different over the last 1000 years. On average, the erosion rates of the LJWD and DJT watersheds were 0.13 Mg ha−1 yr−1 and 1.28 Mg ha−1 yr−1, respectively. Overall, the erosion rate in the areas with severe rocky desertification was obviously small in the past millennium, and there was no serious soil loss. This result indicated that rocky desertification developed at least 1000 years ago. Pollen analysis indicated that soil erosion changes in both watersheds over the past 1000 years were well correlated with the change in crop pollen indicating human farming activities. Based on changes in the content of different types of pollen in sediments, the change in soil erosion can be linked to the change in land use and vegetation landscape. Overall, this work improves our understanding of the relationship between soil erosion and agricultural activities and vegetation landscape change in karst watersheds.

A study on coupling of the grassland pattern and the flood process in Poyang Lake based on the island biogeography theory

Abstract As a typical type of landscape in Poyang Lake, the largest freshwater lake in China, grassland has been deeply disturbed by the flooding process. However, how the vegetation landscape diversity responds to the flooding process of Poyang Lake remains unclear. In this paper, we randomly selected 10 grasslands in the period of a normal water level from 2010 to 2019 to study the coupling relationship between the vegetation landscape diversity and flooding process, and established the related models based on the island biogeography theory. The results are as follows. (1) There is a positive correlation between the grassland vegetation landscape diversity and grassland area, the best fitting model is the logarithmic function. (2) Using the general dynamic model of island biogeography as a reference, the model of diversity–area–flooding established by using the area of grassland and duration as predictor variables has the highest goodness-of-fit. (3) If grassland was flooded for 120–130 days and the maximum depth of flooding is not more than 2.5 m every year, the vegetation landscape diversity in grasslands will be the highest. The findings have provided an extension to the study of the response of vegetation to flooding processes, and provide a certain theoretical basis for the protection and management of the Poyang Lake ecosystem.

국립공원 아고산대 독립훼손지 복원식생 분포특성 및 관리방안

This study was conducted to provide basic data for mid-to long-term monitoring and establishment of management plans by analyzing the existing vegetation and identifying the vegetation distribution characteristics for the restored vegetation in Nogodan and Seseokpyeongjeon in Jirisan National Park located in the subalpine zone among the independent damaged areas. Actual vegetation survey range was established in consideration of the distribution of the watershed around the damaged area. The surveyed area of Seseokpyeongjeon was 55,037㎡, and the surveyed area of Nogodan was 166,599㎡. In Seseokpyeongjeon, the vegetation coverage by the herbaceous layer was almost 90% or more, there was no bare exposure, and the coverage of the shrub layer was stabilized at 60% or more. The main emerging tree species were planted species such as Abies koreana, Betula ermanii, Fraxinus sieboldiana, Rhododendron schlippenbachii, Rhododendron mucronulatum var. ciliatum, and Weigela florida as well as natively migrated native species. In Nogodan, the shrub vegetation dominated by Quercus mongolica, Salix caprea, Rhododendron schlippenbachii, Rhododendron mucronulatum var. ciliatum, and Tripterygium regelii was the most widely distributed with 52% of the area, and the overall diet was good. The native vegetation of Nogodan was presumed to be a cypress colony. Naturalized plants were distributed in the military base demolition site, so active management was required. The study site was predicted to develop into a vegetation landscape in harmony with the surrounding natural vegetation in the long term. In the future, the restoration model for damaged areas should be set in consideration of the native vegetation of the nearby area, but the goal to achieve restoration should be set at a feasible level.

UAVs Technology as a Complementary Tool in Post-Fire Vegetation Recovery Surveys in Mediterranean Fire-Prone Forests

Forest fire is a recurring and serious environmental hazard, which is often due to the interaction between anthropogenic activities and climate change, despite having always characterized the vegetation landscape in the Mediterranean area. Alongside the required prevention and control works, there is an increasing need for post-fire monitoring. This is particularly relevant when it comes to natural or semi-natural forests, so that inappropriate reforestation is not undertaken without having well understood the dynamics of self-regeneration and the resilience of pre-existing phytocoenoses to fire. These monitoring operations often take a long time, but a quick picture of the severity of the fire and the response of the vegetation is also required. In this context, the data relating to post-fire surveys on a maritime pine forest of Monte Pisano (northern Tuscany, Italy), obtained from ground surveys and drone shots, are reported. This investigation showed: (1) UAV technology has proved to be very useful and fast, and it allows a good identification of tree/shrub species and forest structural parameters. (2) In these forests, repeated fires cause the disappearance of pine woods ad substitution with “pyroclimax” cork oak communities in equilibrium with a regime of repeated fires. (3) These first results, part of an ongoing investigation, contribute to a better understanding of the sylvogenetic processes following the passage of fire and can support the management of burned areas.

Conditions of Mainland China’s Island Ecosystems and Associated Influencing Factors: Integrated Assessment of 42 Typical Island Ecosystems

Although China possesses a large number of islands, knowledge of their overall ecological condition is limited on a national scale. Accordingly, this study developed a comprehensive and quantitative island ecosystem assessment framework that incorporates environmental quality, biological structure, and landscape patterns. The framework was applied to 42 typical, representative islands within China’s coastal regions, including different climatic zones, area sizes, populations, and substratum lithologies. Results showed that the value range of the comprehensive index of island ecosystem condition (CIisland) was significant (from 52.33 to 89.53, 71.72 average), and 85.4% of islands scored either “high” or “good,” indicative of their exceptional condition. However, conditions varied among different island components, indicating different challenges. Environmental quality index (Ienv) values ranged from 60.70 to 94.80 (79.72 average), where primary threats were seawater nutrient pollution, petroleum, and marine organism metal contamination. Biological structure index (Ibio) values ranged from 43.50 to 89.40 (66.10 average), where primary threats were vegetation destruction and a reduction in marine biodiversity within intertidal and subtidal zones. Landscape pattern index (Iland) values varied significantly (from 6 to 100, 72.36 average), where a key characteristic of highly developed islands was low natural landscape (vegetation) coverage. Conditions also varied among island climate zones, lithologies, area sizes, and levels of human habitation. Additionally, island ecosystem conditions were influenced by both natural and anthropogenic factors as well as area size, population, and GDP. Although distance to the mainland significantly correlated to (Ibio), and (CIisland), these parameters did not significantly correlate to (Ienv), which might be explained by that environmental quality was generally conditional on large-scale environments. This assessment is intended to provide a holistic perspective on island conditions in China while identifying key challenges and associated driving factors, which will greatly aid in establishing island-specific sustainable management practices.

Distribution of ground-dwelling arthropods across landscapes with intensive agriculture in temperate areas

The idea that land use in the surroundings may affect the abundance of arthropods on a location plays an important role in the argument that agriculture is the prime cause of the recently discovered general decline of insects. We studied the abundance of ground-dwelling arthropods in agricultural fields along a gradient of increasing distance from (semi)natural areas and in relation to landscape complexity in both the North America (Illinois, USA) and Europe (The Netherlands) using pitfalls. Our results showed that the total abundance did not change with distance when we controlled for vegetation height and landscape complexity around the sample locations. Vegetation height affected abundance positively in crop land and negatively in grassland. Landscape complexity only affected abundance when it was measured in a 6000 m radius around sample location, not at lower levels of scale. We conclude that an effect of increasing landscape complexity may be expected when that is done on a large enough scale.

A Novel Spectral Index to Identify Cacti in the Sonoran Desert at Multiple Scales Using Multi-Sensor Hyperspectral Data Acquisitions

Accurate identification of cacti, whether seen as an indicator of ecosystem health or an invasive menace, is important. Technological improvements in hyperspectral remote sensing systems with high spatial resolutions make it possible to now monitor cacti around the world. Cacti produce a unique spectral signature because of their morphological and anatomical characteristics. We demonstrate in this paper that we can leverage a reflectance dip around 972 nm, due to cacti’s morphological structure, to distinguish cacti vegetation from non-cacti vegetation in a desert landscape. We also show the ability to calculate two normalized vegetation indices that highlight cacti. Furthermore, we explore the impacts of spatial resolution by presenting spectral signatures from cacti samples taken with a handheld field spectroradiometer, drone-based hyperspectral sensor, and aerial hyperspectral sensor. These cacti indices will help measure baseline levels of cacti around the world and examine changes due to climate, disturbance, and management influences.

How can structure and composition of Eucalyptus plantation landscape reduce leaf-cutting ants?

Leaf-cutting ants (Atta spp.) are the main Eucalyptus plantation pests that cause successive defoliation, and productivity losses might be significant. Thus, our objective was to evaluate the influence of vegetation composition and landscape structure on the occurrence of leaf-cutting ants in Eucalyptus spp. plantations neighboring areas of Atlantic Forest vegetation. We collected data on the occurrence of ants (Atta spp.) and the amount of loose soil in each ant colony. We calculated the landscape metrics for the area that we divided in landscape planning unit. We proceeded with information-theoretic approach to identify the best set of models with AICc criteria. We found that 81.1% of the ant colonies had an area of loose soil smaller than 1 m2, and the diversity of Eucalyptus ages, edges of Eucalyptus plantation, and conservation of native fragments have influence on ant occurrence and reduce their effects. So, an increase in vegetation conservation status, decrease of roads that lead to edges in Eucalyptus plantations, and adoption of age mosaics in production areas disrupts ant occurrence. In addition, better functional and structural conditions favor ecosystem services, such as soil and water conservation, through a reduction in the use of formicidal baits.

Vegetation Dispersion, Interspersion, and Landscape Preference.

The spatial aggregation/dispersion of the vegetation in a landscape affects landscape texture, with potentially important implications for its perception. The aim of the study was to investigate how plant dispersion and interspersion in small-scale landscapes could affect garden preference. Dispersion referred to the proximity and distance between plants, and interspersion referred to the degree of intermixing between plants of different species. Fifty-six participants evaluated 40 pairs of landscapes that differed in terms of plant dispersion or plant interspersion. Participants were asked to rate their preference for each pair of landscapes. Furthermore, eye movements were recorded during the viewing time, and the number of fixations and fixation time were computed for each landscape image. Overall, plants arranged in a more dispersed and a more interspersed design resulted in a higher landscape preference. Dispersion was more effective than interspersion in affecting landscape preference. The number of fixations and fixation time were higher when viewing landscapes with plants arranged in a high-dispersion and high-interspersion layout.

Cold Stress, Freezing Adaptation, Varietal Susceptibility of Olea europaea L.: A Review.

Olive (Olea europaea L.) is an evergreen xerophytic tree characterizing vegetative landscape and historical-cultural identity of the Mediterranean Basin. More than 2600 cultivars constitute the rich genetic patrimony of the species cultivated in approximately 60 countries. As a subtropical species, the olive tree is quite sensitive to low temperatures, and air temperature is the most critical environmental factor limiting olive tree growth and production. In this present review, we explored the detrimental effects caused of low temperatures on olive cultivars, and analyzed the most frequently experimental procedures used to evaluate cold stress. Then, current findings freezing stress physiology and gene are summarized in olive tree, with an emphasis on adaptive mechanisms for cold tolerance. This review might clear the way for new research on adaptive mechanisms for cold acclimation and for improvement of olive growing management.

Soil Microbial Distribution Depends on Different Types of Landscape Vegetation in Temperate Urban Forest Ecosystems

Although soil microbes play an important role in the functioning of the forest ecosystem, our understanding of the spatial distribution characteristics of soil microbes among different vegetation types in urban forest ecosystems is poor. In this study, with the help of high-throughput sequencing, we examined the vegetation type preferences of soil microbes (fungi and bacteria) and then analyzed the microbe–environment (plant community, light availability, soil properties) relations in a temperate urban forest in China. Our results showed that the soil microbial (bacterial and fungal) richness of deciduous forest was higher than that of evergreen, and mixed forests. The spatial distribution of fungi was more specialized than that of bacteria among different vegetation types. The driving forces of environmental factors on soil bacteria and fungi were different. Our findings suggest that different vegetation types favor the occurrence of different microbes, and the relationships between soil microbes and environmental factors depend on different vegetation types in this temperate urban forest. These findings shed new light on the biodiversity conservation of microbes in temperate urban forests and point to the potential importance of vegetation types for microbe formation.