Different Stages Of Succession Research Articles

Recovery status of coastal vegetation in Mozambique: Insights from floristic composition and soil organic carbon analysis

The growing demand for land for slash-and-burn cultivation, driven by human population growth, has led to the creation of scattered cultivated fields and a mosaic of fallow areas in various stages of regeneration. While tropical forests have demonstrated the ability to rebound regarding tree species diversity and forest structure following disturbances, the extent of recovery in coastal vegetation in southern Africa remains uncertain and poorly understood. To address this knowledge gap, our study collected biophysical data from smallholder fields, fallow land, and forests to evaluate the structure and functioning of coastal vegetation in Gaza province, southern Mozambique. We established 90 sample plots of 0.1 ha each at different stages of plant succession using opportunistic sampling approach. Within these plots, we recorded the diameter at breast height, total height, and species name of all trees and shrubs. Litter and soil samples were collected in 1 m² quadrats embedded within the main plot. Our findings indicate a high capacity for regeneration following the disturbance caused by slash-and-burn cultivation. Species composition varied significantly across different stages of succession, with 52 species identified in forests (FL), 34 in old fallow (OF), 29 in middle fallow (MF), 28 in initial fallow (IF), and 15 in cropland (CL). Richness and diversity increased over time after the practice of slash-and-burn cultivation, with a noticeable enhancement from the initial fallow stage. We observed a gradual recovery of soil carbon stocks in young fallow areas, while litter biomass decreased throughout the recovery phase of the fallow lands. Our study highlights that areas abandoned after agriculture can regenerate in terms of structure, floristic composition, and tree carbon content.

Population Structures and Dynamics of Rhododendron Communities with Different Stages of Succession in Northwest Guizhou, China.

To explore the population structures and dynamics of Rhododendron shrub communities at different stages of succession in northwest Guizhou, China, this study examined the populations of Rhododendron annae and Rhododendron irroratum shrub with two different stages. A space-for-time substitution was employed to establish the diameter class/height structures, static life tables, and survival/mortality rate/disappearance rate curves of both Rhododendron populations with different orders of succession. Their structural and quantitative dynamics were analyzed, and their development trends were predicted. The results showed that, quantitatively, the populations of R. annae and R. irroratum in the two Rhododendron communities with different orders of succession were dominated by age classes one, two, and three as well as height classes i, ii, and iii. The number of Rhododendron plants at the three age classes and the three height classes accounted for 97.61-100% of the total. The quantitative dynamic indices of R. annae and R. irroratum were both greater than 0, with and without considering external interference. In terms of age class and height structures, both Rhododendron populations were expanding populations, presenting "inverted-J-shaped" and irregular pyramid patterns. There was a sufficient number of young individuals, but few or no old individuals. Both survival curves of the populations of R. annae and R. irroratum in the two Rhododendron communities with different orders of succession belonged to the Deevy-II type. In the late stage of succession, the mortality curves and disappearance curves of both Rhododendron populations in these communities presented a trend of increasing first and then decreasing with increasing age class. This result indicates that at each age class, R. annae and R. irroratum showed a trend of gradual increase after two, four, and six years. In brief, the populations of R. annae and R. irroratum have rich reserves of seedlings and saplings, but high mortality and disappearance rates. In this context, it is necessary to reduce human interference and implement targeted conservation measures to promote the natural renewal of Rhododendron populations.

Unveiling hidden interactions: Microorganisms, enzymes, and mangroves at different stages of succession in the Shankou Mangrove Nature Reserve, China

Understanding the interactions between microorganisms, soil extracellular enzymes, and mangroves is crucial for conserving and restoring mangrove ecosystems. However, the unique environments associated with mangroves have resulted in a lack of pertinent data regarding the interactions between these components. Root, stem, leaf, and soil samples were collected at three distinct stages of mangrove succession. Stoichiometry was employed to analyze the carbon, nitrogen, and phosphorus contents of these samples and to quantify extracellular enzyme activities, microbial biomass, and various physicochemical factors in the soil. The results showed that the trends of C, N, and P in the mangrove plants were consistent. Microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), and microbial biomass phosphorus (MBP) were the highest in the Kandelia obovate community. Catalase (CAT) and β-D-G showed the highest content in K. obovate and Bruguiera gymnorrhiza, whereas cellulase showed the opposite trend. Urease was least abundant in the K. obovate community, whereas neutral protease (NPR) and acid phosphatase (ACP) were most abundant. The overall soil environment in mangroves exhibited a state of N limitation, with varying degrees of limitation observed across different succession stages. The demand for P became more intense in the later stages of succession, particularly in the K. obovate and B. gymnorrhiza communities. In conjunction with correlation analysis, it indicated that the input of mangrove plant litter had a significant regulatory influence on the C, N, and P contents in the soil. There was a significant positive correlation between MBC, MBN, and MBP, indicating synergistic effects of C, N, and P on soil microorganisms. Therefore, evaluating the nutrient ratios and sufficiency of mangroves allowed us to comprehensively understand the present environmental conditions. This study aims to develop sustainable management strategies for the conservation and restoration of mangroves.

Primary ecological succession of marine communities on the Tajogaite lava flows (La Palma, Canary Islands), fishes colonize faster than macroinvertebrates and algae

We studied the primary succession of benthic communities in the lava flows of the Tajogaite volcano at 2, 4.5, and 7 months after the eruption ended. The lava from the Tajogaite created several lava flows and sterile rocky reefs that were monitored in both intertidal and subtidal areas up to 20 m depth. Sampling included macroinvertebrates and algae in the intertidal, and fishes, macroinvertebrates, and algae in the subtidal. A control zone was selected to compare the early colonisation of lava flows with that of a mature ecosystem. Colonisation of the lava flow was swift, with numerous species arriving and proliferating soon after the eruption ended. After 7 months, the total number of species recorded in the lava flows was 70, representing 64% of those found in the control zone. thus, communities were gradually becoming increasingly complex owing to the continuous incorporation of species. The number of fishes, and macroinvertebrates in both the intertidal and subtidal, lava flows increased progressively, approaching the values of the control zone. However, algae, in terms of total cover, presented values similar to the control zone from the beginning of the monitoring. All the communities have followed the same trajectory to converge towards communities like those in the control zone, although the rate at which they have changed with time differs. After seven months, differences in fishes between lava flows and the control zone were small, but they were still large with respect to macroinvertebrates and algae. Thus, according to each community of organisms, the benthic ecosystem of the lava flows was found at different stages of succession.

Patterns of floral resources and pollination interactions along dry grassland succession

Succession following the abandonment of traditional management practices can pose severe consequences for the conservation of semi-natural dry grassland communities. In the present study, we investigated whether the quantity of floral resources changes during succession of semi-natural dry grasslands and how this is related to pollinator richness and the number of pollination interactions at the community level. We addressed this issue by quantifying floral resources (i.e., number of flowers, nectar volume and number of pollen grains) and monitoring pollination interactions in dry grassland communities at different stages of succession, defined as the total cover of plant species of forest edges. The relationship between the quantity of floral resources and cover of plant species of forest edges was significantly hump-shaped, i.e., regardless of the type of floral resource, all peaked at intermediate values of cover of plant species of forest edges. The richness of animal-pollinated plants in bloom also showed a hump-shaped relationship with the cover of plant species of forest edges, while the richness of pollinator species and the number of pollination contacts were indirectly related to the cover of plant species of forest edges, as they were significantly associated with the number of flowers and the richness of animal-pollinated plants in bloom. Results suggest that succession of dry grasslands after abandonment may affect a crucial function in terrestrial ecosystems, namely animal-mediated pollination. Nevertheless, the conditions of early succession, which could be achieved by the presence of scattered shrubs, could ultimately be favourable for the pollination function in dry grasslands.

CONTENT OF HEAVY METALS IN THE PHYTOMASS OF THE NATURAL MEADOWECOSYSTEMS OF VINNYTSIA REGION UNDER GENERAL BACKGROUND POLLUTION AND AS A RESULT OF ANTHROPOGENIC TRANSFORMATION OF LAND

Meadows as plant ecosystems of the Forest-Steppe zone are secondary in origin. They were formed on the site of indigenous (primary) vegetation types – forest or marsh ecosystems – after being transformed by humans to meet the needs of agriculture or livestock. In ancient times, the areas that are now occupied by meadows were mostly covered by forests or swamps. With population growth and livestock development, these forests were cut down, swamps drained, and the land was used for agricultural production as pastures and hayfields. Meadows on the plains of former forest or marsh ecosystems are unstable dynamic phytocoenoses in different stages of succession. Therefore, dominant species' botanical composition and projective cover change rapidly, requiring constant human intervention to maintain their high productivity. Following the principles of sustainable development, one of the most urgent tasks is to provide the population with a sufficient amount of high-quality and safe food of both plant and animal origin. It is known that the quality and safety of food products are directly dependent on the environmental conditions of food raw material production. Vegetation of natural fodder lands is an important element of livestock production, which is characterized by low cost compared to cultivated lands. However, in some areas, natural fodder lands undergo a strong anthropogenic load in technogenesis, leading to soil contamination with various toxicants, particularly heavy metals such as Pb, Cd, Zn, and Cu. The main sources of pollution of natural fodder lands are industry, motor vehicles, chemicalisation of the crop production sector, and others. Under such conditions, the use of phytocoenoses as feedstock for both domestic and wild animals increases the risk of heavy metals entering their bodies, which threatens the production of safe and high-quality products, and contaminated soils may be withdrawn from agricultural use. The study aimed to determine the levels of accumulation of Pb, Cd, Zn, and Cu in the ecosystems of natural fodderlands under different anthropogenic loads in the conditions of Eastern Podillia in Vinnytsia region.

Ecomorphological groups in oribatid mite communities shift with time after topsoil removal – Insight from multi-trait approaches during succession in restored heathlands

Restoration of nutrient-enriched heathlands and similar dry habitats via topsoil removal requires the re-assembly of above and belowground communities to attain fully functional ecosystems. Top-soil removal provides unique opportunities to study the assembly processes, but research has traditionally focused on succession of the aboveground part of the ecosystem. Oribatid mites are a dominant group of soil mesofauna in the belowground part of heathlands. They possess attributes for bioindication and have shown high sensitivity to environmental changes during succession. However, few studies have focused on changes in functional community profiles and the factors shaping them with time. We sampled heathlands of different restoration ages located in East Belgium, studied traits of oribatid mite communities of a chronosequence, and assessed the interaction between traits and abiotic variables using community weighted means (CWM) and an iterative co-correlation analysis between abiotic parameters, species trait attributes and species abundances (iterative RLQ analysis). Our study suggests that moisture preferences, concealability (i.e. defence mechanism against desiccation and predation), and body length were the dominant traits structuring the oribatid mite communities. We found that both dispersal and environmental filters shape the assembly of oribatid mite communities, but these drivers dominate different stages of succession. Moreover, trait assemblages deriving from three well-defined eco-morphological groups closely followed these constraints in time. Thus, the shifting dominance of specific groups provides valuable insight on the soil community functioning in a changing environment.

Changes of soil organic matter stock in meadow ecosystems in the south of Western Siberia

The study was conducted on the Baraba plain in the southern part of Western Siberia. Soil samples in meadow ecosystems that are at different stages of succession after drying of the lake bottom were analyzed. The conducted research allowed us to establish that the content of soil organic matter and microbial biomass (the active part of soil organic matter) in successional ecosystems formed in the floodplain of the drying salt lake gradually increases and in the last stages of development reaches the values of zonal chernozem soils. The process of accumulation of carbon stocks of humus and microbial biomass slows down against the background of a high concentration of salts in individual horizons of young soil profiles. This may be the reason for the revealed pattern, according to which the main carbon stock of humus and microbial biomass are concentrated in the upper (0-10 cm) layer of the emerging soils. This is especially noticeable at the very first initial stage of soil development and the next stage of the salicornia community (Salicornia perennans). In the last stages of succession, solonetz and chernozem-meadow soils are formed under meadow ecosystems. The carbon stock of humus and microbial biomass at these stages of soil development significantly increase against the background of active processes of reducing the amount of salts in the profiles of meadow soils. And only at these last stages there is a significant increase in carbon stocks of humus and microbial biomass in a layer of 10-20 cm.

Effects of deglaciation on the succession of methanotrophic communities in inland and tidewater glaciers in the high Arctic, Svalbard

The high Arctic region of Svalbard has undergone significant landscape transformations due to accelerated deglaciation driven by climate warming. The expansion of exposed soil surfaces during rapid deglaciation provides new habitats for plants and microorganisms and contributes to ecosystem succession. The primary succession process has the potential to impact methane flux by influencing the activities of methanotrophs and methanogens. While the primary succession of plant communities following glacier retreat has been extensively studied, microbial succession, in particular that of methanotrophs and methanogens, is still poorly understood. Moreover, previous investigations have focused on the forelands of inland or mountainous glaciers, neglecting those of tidewater glaciers that extend to the coastal line. In this study, we investigated the abundance of methanotrophs and methanogens, as well as methanotrophic communities along a 100-year soil chronosequence in the forelands of inland and tidewater glaciers in Svalbard. The abundance of methanotrophs showed a gradual increase with soil age in both glacier types, while the abundance of methanogens exhibited significant differences only in tidewater glaciers. Our results revealed clear trends in the structure of methanotrophic communities with an increase in their diversity during the deglaciation process in both glacier types. These trends were mediated by changes in soil physicochemical properties such as soil organic carbon and total nitrogen. Our findings indicate that methane oxidation may be enhanced by the increase in the abundance and diversity of methanotrophs in both glacier types throughout the successional stages, and that carbon and nitrogen contents play a crucial role in structuring the community at different stages of succession in the glacier forefield. These insights significantly contribute to our understanding of microbial dynamics during deglaciation and their implications for methane dynamics in the high Arctic.

Bryophytes from the Sítio do Rangedor State Park, Maranhão, Brazil

The Sítio Rangedor State Park is an important conservation unit in an urban area with remnants of Amazon Forest in different stages of succession. The Park presents a characteristic bryophyte flora and can be useful to evaluate the local environmental quality. The objective of this study was to survey the diversity, distribution and ecological aspects of bryophytes in this Conservation Unit. The specimens were collected on different substrates throughout the area during the rainy and the dry season. Sixteen species of bryophytes were recorded, 15 moss species and one liverwort species. Most taxa are widely distributed and well represented in all phytogeographic domains; only Garckea flexuosa (Griff.) Margad. & Nork. presented a rare distribution. Microcalpe subsimplex (Hedw.) W.R. Buck and Weisiopsis bahiensis (Müll. Hal.) Broth. are endemic to Brazil, and the latter is a new record for Maranhão. There was a predominance of life forms with high (tuft) and intermediate (mat and weft) tolerance to desiccation, as well as generalist species as to tolerance to light incidence. Information on global and national geographic distribution, functional groups and endemism is provided. The most abundant species was Hiophyla involuta. (Hook.) A. Jaeger. Acrocarpous growth predominated among mosses. Calymperes palisotii Schwägr. presented investment in resistant propagules, reflecting the highly seasonal climate of the region. The data provide a basis for future investigations and reinforce the need for greater efforts aimed at environmental education activities in the area. Further, the registration of rare and endemic reinforces the importance of the conservation of this area.

Bird population dynamics during the regenerative succession of mossy pine woodland in southwestern Belarus

Disturbed forest ecosystems are characterized by significant spatial and temporal changes. As a part of the study on bird communities, changes in bird abundance during the secondary succession of a cleared mossy pine woodland in southwestern Belarus were investigated. The purpose of the work was to determine the inter-annual dynamics of bird species abundance and to assess the variability of individual species abundance during the secondary succession of the mossy pine woodland. The material was collected in 2000–2019. Line transects were set to conduct bird counts in ecosystems at different stages of succession. For the data processing, generally accepted methods of statistical analysis were used. The species diversity of birds was found to increase from 8 to 42 species, the overall abundance from 171.7 to 587.1 birds/km2 during the succession (6 stages, from 1 to 90 years in age). The abundance of species (birds/km2) and inter-annual variability during 11 seasons were determined. The coefficient of variation (CV) was the highest (71.00–82.50%) for species whose abundance did not exceed 1.0 birds/km2. The average abundance of species varied considerably, e.g., among passerines at the 80–90-year old stage from 1.1 birds/km2 (Little Flycatcher) to 153.7 birds/km2 (Chaffinch). Bird populations with high abundance turned out to be the most stable, for example at the last two successional stages the CV of the Chaffinch is 6.02 and 7.16%. For species with average abundance the variability is found to be low or medium (varies from 11.90 to 36.20%), for species with low abundance the CV varies from 17.68 to 82.50%. All six stages of succession were dominated by nesting migratory birds, which account for 75.0% of the species in the first stage of succession to 52.4% in the fifth and sixth stages. Near and distant migrants form the basis of the bird community at all stages. Populations of sedentary species and distant migrants are more stable than those of near migrants.

Mosaic forest management at landscape scale to enhance fungal diversity and production, in a context of forest fire-prevention in Mediterranean ecosystems

Landscapes of oak (Quercus) forests alternated with extensive fields dominated by rockroses (Cistus) are widespread throughout the Mediterranean Basin. Due to the recurrency of fires and the mycological potential of both Quercus forests and Cistus fields, adequate management of this landscape is a key forest management objective. Although both Quercus and Cistus species are considered super-productive in terms of fungal production and diversity, fungal diversity and productivity vary depending on the stand age and structure. The aim of this study was to assess the complementary mycological potential of these ecosystems by studying sporocarp production, diversity, and community composition to elucidate management practices that would enhance fungal diversity and productivity within a fire management framework. We collected sporocarps over a period of four consecutive years (2012–2015) in young Cistus plots (1-m tall Cistus), old Cistus plots (2-m tall Cistus), and Quercus Forest plots. Our analyses showed that age as well as dominant vegetation influences sporocarp production, diversity, and richness, with young Cistus stands most suited to high levels of sporocarp productivity and diversity. In addition, a progressive restructuring of the fungal community was observed from a large, diverse community in Cistus early-stage stands to a smaller, less diverse but well-defined community in Quercus stands, transiting through an intermediate composition in old Cistus fields. Based on our findings, we suggest that a management process that not only favors stand rejuvenation would achieve greater sporocarp production and richness, including edible commercial species, while reducing the amount of fuel. In addition, the differentiated diversity of the Quercus stands plays an important role in terms of landscape diversity, being necessary the recommendation of a rejuvenation management in order to protect this stands associated diversity. We propose that these goals could be best achieved with a mosaic landscape model to connect the different stages of succession, enabling greater interconnectivity and, hence, allowing the presence of different “fungal stages” at the landscape level.

De wording van een uniek verveningslandschap: de Molenpolder bij Westbroek

The creation of a unique peat landscape: the Molenpolder near Westbroek (province of Utrecht) In the Middle Ages most of the peatlands in the western part of the Netherlands were turned into agricultural land. In the Early Modern period large parts of this peatland were dug up in order to provide the upcoming towns and cities with fuel. This process of extraction – even below the ground water line by dredging –was still going on in some parts at the beginning of the 19th century when the land registry (Kadaster) was rolled out. This is the case in Molenpolder, a settlement north of the city of Utrecht, which today is a nature reserve. The strips of land (‘legakkers’) on which the peat was laid to dry and the peat holes in between are well preserved. The cadastral map offers a snapshot of how these strips were formed. The lord of the manor of Westbroek wanted to prevent all of his domain being turned into water and in 1790 started researching which part was best suited for peat extraction. A map of this research shows equally sized parcels which according to the Kadaster map (1832) were divided among the farmers in the vicinity, resulting in a mosaic of ownership. After the period of peat extraction, a process of hydrosere took place. The mosaic of ownership and therefore different levels of maintenance of each parcel resulted in a mosaic of different stages of ecological succession. After World War II a process of forestation started. Today the landscape is a mosaic of ponds, small pastures, marsh woodland, quake and thatch fields and other stages of ecological succession.

An Early Cretaceous sponge meadow from the Neuquén Basin, west-central Argentina: unsuspected hosts of a dynamic sclerobiont community

ABSTRACTSponges, especially Calcarea, are minor components of benthic associations, especially during the Mesozoic. In the Lower Cretaceous of the Neuquén Basin, small calcareous sponges have been found building a small monospecific meadow. It is restricted to a marlstone lens-shaped bed in a quiet outer-ramp setting in the Cerro Marucho Locality (Picún Leufú depocentre), above a shell bed of small exogyrid oysters; oysters and sponges were the only preserved macrobenthic faunal elements. Individual sponges were small, under 4 cm high, and presented a sub-cylindrical morphology with one or more rounded, apical osculi, many inhalant openings and triactine spicules. Specimens studied here were assigned to Endostoma sp. aff. Endostoma nodosa. These sponges are quite commonly encrusted by exogyrid oysters, serpulids, sabellids, agglutinating foraminifers and cyclostome bryozoans. Overgrowths among sclerobionts were common, though no undoubtedly in vivo interaction has been recorded. Disarticulated left oyster valves were frequently bioclaustrated by the sponges, showing that in vivo settlement upon sponges was common. Many oysters settled in the periphery of the osculum suggesting a commensal relationship. The study of this sponge meadow and its sclerobiont community allowed the identification of different stages of ecological succession. The pioneer stage was characterised by sponge settlement on oyster valves, within an otherwise soft consistency bottom. High sedimentation or high nutrient inputs, either individually or in combination, could explain the great abundance of oysters. During the climax stage, sponges thrived and harboured several sclerobiont taxa, developing a relatively dynamic palaeocommunity. Finally, an intensification in either sedimentation rates or nutrient input (or both) past the tolerable threshold for sponges may have been the cause(s) of the meadow's demise. Endostoma and similar forms were up to now reported mostly from the Jurassic and Cretaceous of Europe as accessory builders, or as accompanying fauna in reefal settings. This new record shows that in rare occasions they could form low-relief meadows on their own.

In the bleak mid-winter: The value of brownfield sites for birds during the winter

Brownfield sites (e.g., wastelands, disused industrial grounds and power stations) are valuable refuges for urban birds during the breeding season. This owes to the presence of vegetation in different stages of succession, which provide a high diversity of food and breeding resources. However, insufficient research has explored their winter value, when temperatures are lower and food is scarcer. Accordingly, 342 bird and habitat surveys were conducted in brownfield sites, and other land-uses, across Greater Manchester. Bird density estimates were then calculated using Distance software and bird-habitat associations were analysed using Canonical Correspondence Analysis (CCA). Moreover, the impact of brownfield site development on winter bird density from 2000 to 2009 in Greater Manchester was explored using the bird density estimates, and historical image function in Google Earth. In brownfield sites, Pica pica had the highest density estimate (142 per km2), although four species had estimated densities > 100 per km2 (Turdus merula; Cyanistes caeruleus; Passer domesticus; Aegithalos caudatus). The CCA indicated that Aegithalos caudatus, Cyanistes caeruleus, Parus major, Prunella modularis were associated with Fagus sylvatica, Betula pendula, and Buddleja davidii on brownfield sites, which during the winter 1) produce seeds 2) support overwintering insects, providing a valuable food source. Nevertheless, across land-uses, most species favoured green space and pre-2000 housing. Brownfield sites were most replaced between 2000 and 2009, with 17.8 km2, 14.9 km2, and 12 km2 replaced by commercial, industrial, and post-2000 housing respectively. This is likely to have had a negative impact on the winter density of most bird species, owing to 1) the removal of brownfield site vegetation 2) increases in impervious land cover. Future declines in winter bird abundance could be mitigated by retaining brownfield site vegetation and setting aside brownfield sites in close proximity to green space and pre-2000 housing.

Characteristics of soil carbon emissions and bacterial community composition in peatlands at different stages of vegetation succession

Microorganisms are important components of soil ecosystems and play an important role in material cycles. Northern peatlands are important ecosystems in middle-high latitude regions. In peatlands, different vegetation successions occur with changes in groundwater levels. The overall carbon emission of peat bogs is related to the carbon stability of the surrounding environment. Unraveling the assembly and distribution of bacterial communities at different succession stages in peatland is essential to understanding the soil nutrient cycle. In this study, we investigated the characteristics of soil carbon emissions and the composition of subsurface microorganisms under six different succession stages. The highest carbon emission was observed in mossy peatlands, and their soil enzyme activity was closely related to the aboveground vegetation cover type. The succession pattern of ground vegetation was the main driver of soil microorganisms. The abundance of the dominant Proteobacteria decreased with increasing soil depth, while the opposite trend was observed for Chloroflexi. Furthermore, the community structure of microorganisms became progressively simpler and looser as soil water content decreased. The bacterial alpha diversity was driven by soil dissolved organic carbon and Fe, and the beta diversity was driven mainly by soil water content. The bacteria presented a random distribution in a nutrient-rich soil environment and shifted to deterministic distribution with decreasing water and nutrient contents. The balance between taxonomic diversity and dispersal limitation mediates species coexistence in the soil microbiome. This study provides new insights into the soil environment at different stages of succession in peatlands.

Increased survival rate of Quercus aliena var. Acuteserrata seedlings via nitrogen addition for the succession of pine and pine-oak mixed forests to oak forest

Forest regeneration mechanisms of Pinus tabulaeformis, Pinus armandii, and Quercus aliena var. acuteserrata as the constructive species have been the focus of ecologists and silviculturists, and research to better understand the future of forest community composition, succession patterns, and other aspects of far-reaching influence. However, the influence of nitrogen deposition on the regeneration of different succession stages needs further investigation. In this study, seedlings of the three species of different ages were planted in the pine, pine-oak mixed, and oak forests, and the seedlings which planted by the pot culture with natural soil or fertilization soil, were monitored for two years. Survival and growth indicators, chlorophyll content, and foliar nutritional status of the seedlings were measured. The survival rate and chlorophyll content of P. tabulaeformis, P. armandii, and Q. aliena var. acuteserrata seedlings were the lowest in the oak forest, which might be related to the availability of light in the undergrowth at different stages of succession. Regardless of the forest type, after nitrogen addition, the survival rates of P. tabulaeformis and Q. aliena var. acuteserrata seedlings were the highest for 4-year-old seedlings, and the survival rate of P. armandii seedlings was the highest for 10-year-old ones. Nitrogen addition had no significant effect on the survival rate of P. tabulaeformis and P. armandii seedlings, but changed the nutrient content in their leaves. However, the addition of nitrogen improved the survival rate of Q. aliena var. acuteserrata seedlings, and their competitiveness. Therefore, it can be inferred that nitrogen deposition may promote the succession of P. tabulaeformis forest- to oak forest-in the Qinling Mountains, China.

Assemblage Characteristics of Butterflies and Carabid Beetles as a Function of Soil Characteristics and Plant Diversity in Differently Managed Fields, Forests and Ecotones: A Case Study in Tuczno Forest District, Poland

A drastic decline in insect fauna on a large scale has been reported. We assume that this is a multifactorial problem involving biotope types and plant diversity, soil characteristics and human activity (management of areas). The aim of our study was to analyze diversity patterns of carabid beetles and butterflies as predatory and phytophagous arthropod groups in response to soil characteristics and plant diversity in different types of ecosystems and ecotones with diverse management situated in a heterogeneous landscape composed of different forests, agricultural and post-agricultural areas of different stages of succession and watercourses and mires in north-western Poland. Three different forests, three fallows, two meadows and two ecotones, differing with respect to the involved ecosystems, were included in the study. Our results showed that the study site types differed with respect to soil characteristics and plant diversity, but ecotones were not characterized by explicitly higher diversity in these parameters. For both carabid beetles and butterflies, characteristic assemblages for individual study sites could be demonstrated. We could also show differences in the most important factors between these two taxonomic groups. We assume that management type is important regarding ecosystem characteristics and biodiversity. Large-scale management strategies are necessary in order to maintain or create landscapes with high natural qualities.

Dynamics of medical plants in the course of regeneration successions after clear cutting

The goal of the study was to elucidate the peculiarities of changes in the coverage of medical plants in the course of regeneration successions after clear cutting. 650 sample plots of different stages of succession and types of forest growing conditions were analyzed. It appeared that some species increased their coverage and some of them decreased it. The large group of species did not react to the cutting of the stand.

Contrasting trends in biodiversity of birds and trees during succession following cacao agroforest abandonment

Abstract Understanding how transformed habitats act as reservoirs of biodiversity is a key challenge at a time when ecosystems are under unprecedented pressure. Here we compare tree and bird biodiversity in actively cultivated and abandoned cacao agroforests, and use a space for time approach to ask how this diversity has changed over 100 years of succession. Tree and bird communities were surveyed in cacao agroforests, secondary forests at different stages of succession and primary forests in the Northern Range of Trinidad, West Indies, to test the prediction that there are consistent temporal trends in alpha and beta‐diversity across taxa. Temporal alpha‐diversity was taxon dependent. We found that tree alpha‐diversity increased with forest age. In contrast, there was no temporal trend in bird alpha‐diversity. Tree and bird species richness were negatively correlated. Tree and bird composition varied with forest age and environmental distance. A greater proportion of native trees, and of highly forest‐dependent and insectivorous birds were found in older forests. Our analyses show that actively cultivated and young abandoned cacao agroforests can sustain high bird alpha‐diversity, despite lower levels of tree alpha‐diversity. Old secondary and primary forests have unique species compositions including more sensitive and specialist species. Compositional shifts with successional stage for both trees and birds produce a patchwork of habitats that contribute to regional gamma‐diversity. Synthesis and applications. Our research highlights the value of actively cultivated cacao agroforests and secondary forest alongside primary forests as reservoirs of biodiversity. By supporting both biodiversity and livelihoods, traditionally grown shade‐cacao agroforests fall within a people and nature framework. Taken together, these results emphasise the contributions of secondary forests, which are often overlooked, to conservation.