Semi-natural Vegetation Types Research Articles

Nature on our doorstep: How do residents perceive urban parks vs. biodiverse areas?

The role of nature in enhancing urban well-being is well-established, but perceived naturalness may not always align with scientific definitions. Our study aimed to investigate whether areas selected for nature-related activities demonstrate increased biodiversity, offer diverse experiences, and integrate both social and ecological perspectives. We aimed to bridge the gap between perceived naturalness and objective ecological richness. Integrating social and environmental parameters, we considered both objective indicators, such as the presence of rare species, and subjective perspectives. Extensive geotagged surveys among 401 working-age Warsaw residents, coupled with field analyses, and biodiversity data collected for the scale of the whole city, allowed to juxtapose human perception with tangible ecological indicators. Our results revealed that only 14% of the locations identified by respondents as natural were associated with high biological diversity. In contrast, over 30% were in areas with low biological diversity, lacking rare species. Factors like presence of natural and semi-natural vegetation types, distance from buildings, population density, presence of water, noise, and extreme temperatures were found to be significant. We distinguished four types of natural areas: close to home, open grassland, high naturalness, and forested, reflecting different preferences and alternative choices when high-quality natural areas are not nearby. Most notably, urban parks emerged as key locations for nature contact, even though objective measures of biodiversity were often low. This underscores the need for a comprehensive understanding of how urban residents interact with and value natural spaces, bridging the gap between subjective experiences and objective ecological richness within the city's green areas. Our study highlights the complex interplay between the physical properties of urban green spaces, individual perceptions, and the ecological aesthetics influencing these interactions. In particular, the concept of perceived naturalness emerges as a critical factor, often contrasting with objective, quantifiable naturalness, and necessitating a nuanced approach in urban planning and public health contexts to cater to diverse needs and preferences of city dwellers.

Assessment of butterfly diversity status and conservation issues in Agartala urban localities of Tripura, North East, India

Urbanization leads to a great impact on biodiversity and butterflies (Lepidoptera) are commonly used as a bioindicator species for impact assessment throughout the globe. In order to attain the present status knowledge and conservation issues of butterflies in different impact zones across natural and semi-natural vegetation types, ecopark, residential area, commercial hub etc. in different urban localities of Agartala city, Tripura a random field study was conducted for two years. A total of 76 butterfly species belonging to 6 families and 51 genera were recorded with seasonal variation in their abundance. The family Nymphalidae was dominant in terms of species composition with 28 species and Riodinidae was least one with only single representative. This is the first urban butterfly study in Tripura highlighting present diversity status with some conservation issues like anthropogenic stress, mitigation measures etc. The present report may be useful for environmental impact assessment study in future developmental activities in the study area.

Grazing and fouling behaviour of cattle on different vegetation types within heterogeneous semi-natural and naturalised pastures

In a two-year study, grazing, resting and fouling behaviour of cattle grazing on heterogeneous semi-natural/naturalised continuously grazed, fenced pasture areas (sites), were examined using two and nine sites in year 1 and 2. Five vegetation types were identified and mapped out on the sites used in the study: four typical species-rich semi-natural vegetation types (dry, mesic, wet, shaded), and one naturalised, grass-dominated type on former fertilised arable land. The two sites used in year 1 and seven sites in year 2 contained all five vegetation types, while one or two vegetation types (dry and wet) were absent on the remaing two sites in year 2. Behaviour was recorded over 24 h on three occasions in year 1, and on one occasion in year 2. During observation hours, animal behaviour (grazing/resting/other) and vegetation type grazed were recorded at 5-minute intervals and time and location of defecation and urination were recorded continuously. Vegetation types were sampled for herbage analysis directly after behaviour observations by cutting the vegetation in three random plots per type. Relative preference for grazing, resting and fouling was calculated for each vegetation type by dividing proportion of behaviour observations spent on a specific vegetation type by proportion of total area occupied by this vegetation type. The results showed that during both years, animals showed the greatest relative preference for the naturalised vegetation type when grazing or fouling (urination and defecation). The naturalised vegetation type also had the greatest content of metabolisable energy (from 9.8 to 10.1 MJ/kg DM) and crude protein (from 131 to 157 g/kg DM) and the least content of neutral detergent fibre (from 453 to 456 g/kg DM).

Land surface greening suggests vigorous woody regrowth throughout European semi-natural vegetation.

The satellite record has revealed substantial land surface "greening" in the northern hemisphere over recent decades. Process-based Earth system models (ESMs) attribute enhanced vegetation productivity (greening) to CO2 fertilisation. However, the models poorly reproduce observed spatial patterns of greening, suggesting that they ignore crucial processes. Here, we explore whether fine-scale land cover dynamics, as modified by ecological and land-use processes, can explain the discrepancy between models and satellite-based estimates of greening. We used 500m satellite-derived Leaf Area Index (LAI) to quantify greening. We focus on semi-natural vegetation in Europe, and distinguish between conservation areas and unprotected land. Within these ecological and land-use categories, we then explored the relationships between vegetation change and major climatic gradients. Despite the relatively short time-series (15years), we found a strong overall increase in LAI (i.e., greening) across all European semi-natural vegetation types. The spatial pattern of vegetation change identifies land-use change, particularly land abandonment, as a major initiator of vegetation change both in- and outside of protected areas. The strongest LAI increases were observed in mild climates, consistent with more vigorous woody regrowth after cessation of intensive management in these environments. Surprisingly, rates of vegetation change within protected areas did not differ significantly from unprotected semi-natural vegetation. Overall, the detected LAI increases are consistent with previous, coarser-scale, studies. The evidence indicates that woody regrowth following land abandonment is an important driver of land surface greening throughout Europe. The results offer an explanation for the large discrepancies between ESM-derived and satellite-derived greening estimates and thus generate new avenues for improving the ESMs on which we rely for crucial climate forecasts.

Vegetation Database of the Cilento National Park

A TURBOVEG database, including both original and published phytosociological releves from the Cilento and Vallo di Diano National Park (Southern Italy), was compiled to support environmental monitoring, landscape planning and vegetation classification. Approximately 2,300 releves were stored in the database including all the natural and semi-natural vegetation types, ranging from sand dunes (Cakiletea maritimae) to dwarf shrub subalpine vegetation (Pino-Juniperetea). Data span from 1970 to nowadays, updated with the most recent research project. We considered for inclusion in the database phytosociological releves or any other vegetation plots containing records of species composition (of at least vascular plants) and an estimate of species cover. We extended the standard structure of the database by adding extra fields to fit particular needs, such as including the accuracy of the data location (i.e. a crucial issue for environmental monitoring). A reference check-list of the taxa was set up mostly following Conti et al. (2005) including several largely adopted synonymous to facilitate the correct input of releve data. Ecological databases are linked to the vascular species using Ellenberg indicator values and including life forms or chorotypes. The database contains useful information to test several ecological hypotheses and to perform wide-scale vegetation classifications. Furthermore it facilitates the use of vegetation-plot data for biodiversity and habitat monitoring and also for land use/cover changes evaluation. This report describes the available content in the Vegetation Database of the Cilento National Park (GIVD ID EU-IT-002).

Spatio-temporal patterns in vegetation start of season across the island of Ireland using the MERIS Global Vegetation Index

Spring phenophases such as the beginning of leaf unfolding, measured in the Irish gardens of the International Phenological Garden (IPG) network, indicate an earlier spring occurrence hence a longer growing season. However, these measurements are limited to selected species of trees at a few point locations in the southern half of the country. The aim of this study was to develop a methodology, based on satellite remote sensing, to measure the vegetation start of season (SOS) across the whole island of Ireland on an annual basis, complementary to existing ground-based methods.The SOS metric was extracted for each year in a 7-year time series of 10-day composited, 1.2km reduced resolution MERIS Global Vegetation Index (MGVI) data from 2003 to 2009, based on curve fitting, using the time series analysis software, TIMESAT. Spatio-temporal variability in the SOS was detected across the island on an annual basis and highlighted in a series of anomaly images showing variation from the 7-year mean SOS. The 2006 SOS was late across the island while there were strong geographical gradients to the SOS anomalies in 2009 when it occurred later in the south and earlier in the north. There was a mix of early and late anomaly values throughout the country in the other years.Qualitatively, the spatial patterns in the timing of the SOS were related to the distribution of landcover types as indicated by the CORINE Land Cover map (CLC). Three statistically separable groups of CLC classes were derived from differences in the SOS, namely agricultural and forest land cover types, peat bogs, and natural and semi-natural vegetation types. These groups demonstrated that vegetation in cultivated areas like pastures has a significantly earlier SOS than in areas of unmanaged vegetation such as peat bogs. An initial climate analysis indicated that an anomalously cold winter and spring in 2005/2006 delayed the 2006 SOS countrywide; while a cold winter followed by a mild spring in 2009 caused considerable spatial variability in the 2009 SOS across the country, ranging from later SOS in the south to early SOS in the north.This study has demonstrated the utility of 10-day MGVI composites for derivation of an SOS metric which can be used as an indicator of spatial variability in vegetation seasonality and has highlighted how SOS varies according to landcover type. The availability of longer time series in the future will allow more focused studies on the sensitivity of the SOS metric to changes in climate as well as short term weather events.

Influence of past land use and current human disturbance on non-native plant species on small Italian islands

Biological invasions are regarded as one of the main drivers of habitat degradation in island ecosystems. Mediterranean islands have been subjected to a high degree of land conversion over the past 60 years, resulting in a massive reduction in the amount of rural land and the sprawl of tourist activities. The aims of this paper are to evaluate the current level of invasion of alien plant species in semi-natural vegetation types that have developed after the abandonment of agriculture and to analyze the relationships between non-native species, native flora, and environmental characteristics. Two Italian islands (Ponza and Ventotene) were surveyed using a random-stratified sampling. The occurrence and relative cover of alien plant species were compared and separate analyses were performed for the native flora. Abundance patterns of both native and alien species were then studied in the light of the environmental and anthropogenic features. Although we found that some non-native species are extremely widespread, their relative cover at the plot level is low. Permutational Multivariate Analysis of Variance and Indicator Species Analysis revealed dissimilarities in the native species composition, while Mann–Whitney and Kruskal–Wallis tests showed differences in the ecological requirements (moisture, soil reaction, and nitrogen) of the native species pool. Canonical Correspondence Analysis pointed to the importance of the proximity to agricultural areas, human disturbance, and past land management, particularly residual terraces, in determining the difference between plant communities on the two islands. The results of our study suggest that traditional forms of agriculture may represent a key element for countering the establishment and spread of non-native plants in Mediterranean areas.

Empirical realised niche models for British higher and lower plants - development and preliminary testing

Question: Can useful realised niche models be constructed for British plant species using climate, canopy height and mean Ellenberg indices as explanatory variables? Location: Great Britain. Methods: Generalised linear models were constructed using occurrence data covering all major natural and semi-natural vegetation types (n=40 683 quadrat samples). Paired species and soil records were only available for 4% of the training data (n=1033) so modelling was carried out in two stages. First, multiple regression was used to express mean Ellenberg values for moisture, pH and fertility, in terms of direct soil measurements. Next, species presence/absence was modelled using mean indicator scores, cover-weighted canopy height, three climate variables and interactions between these factors, but correcting for the presence of each target species in training plots to avoid circularity. Results: Eight hundred and three higher plants and 327 bryophytes were modelled. Thirteen per cent of the niche models for higher plants were tested against an independent survey dataset not used to build the models. Models performed better when predictions were based only on indices derived from the species composition of each plot rather than measured soil variables. This reflects the high variation in vegetation indices that was not explained by the measured soil variables. Conclusions: The models should be used to estimate expected habitat suitability rather than to predict species presence. Least uncertainty also attaches to their use as risk assessment and monitoring tools on nature reserves because they can be solved using mean environmental indicators calculated from the existing species composition, with or without climate data.

Baseline characterization of major Iberian vegetation types based on the NDVI dynamics

We present an approach to derive baseline conditions for the radiation intercepted by vegetation in the largest remaining patches of homogeneous vegetation of the Iberian Peninsula. These baseline conditions can serve as a reference to assess environmental changes. We also characterized the major vegetation types of the Peninsula in the functional space defined by the NDVI dynamics and analyzed the climatic controls of NDVI dynamics. We analysed the attributes of the NDVI seasonal dynamics: annual mean (NDVI-I), relative range (RREL), NDVI maximum and minimum values (MAX and MIN), months of MAX and MIN (MMAX and MMIN), and their inter-annual variabilities (1982–1999). We selected as reference sites only homogeneous pixels occupied by natural vegetation. We described their relationship with climatic variables using regression models. NDVI-I and RREL captured most of the variability of the NDVI annual profile. Eurosiberian vegetation types were more productive, with winter minima and summer maxima. Mediterranean vegetation had summer minima and maxima distributed from autumn to spring. Inter-annual differences (higher in the Mediterranean) were low for NDVI-I and MAX and high for RREL and MIN. Precipitation was the main driver of NDVI-I for the Mediterranean pixels while temperature constrained it in the Eurosiberian ones. Seasonality (RREL) was associated with winter temperatures in Eurosiberian areas and with summer drought in Mediterranean ones. The Iberian vegetation types mainly differed in terms of total production and seasonality. Such differences were related to mean and inter-annual variation in precipitation and temperature associated with the Eurosiberian and Mediterranean climate zones. The NDVI dynamics allowed us to identify a functional signature for each vegetation type which captures differences that go beyond their range of climatic factors. Our baseline descriptions, based on a common approach to characterize vegetation functioning, are proposed as reference situations to evaluate the impact of environmental changes on the remaining large patches of single major natural and seminatural vegetation types.

Effects of topography on radiance from upland vegetation in North Wales

Radiance data from a Landsat 5 Thematic Mapper image were used to study terrain effects in 284 4 pixel by 4 pixel quadrats in upland North Wales. The three semi-natural vegetation types examined re...

POST-MEDIEVAL AND RECENT CHANGES IN BRITISH VEGETATION: THE CULMINATION OF HUMAN INFLUENCE.

Although measurable climatic fluctuation in temperature and wetness has occurred between A.D. 1700 and 1984, lack of earlier records and the complicating effects of human influence militate against detection of vegetational response in Britain. Vegetational change during this period is thus regarded as almost entirely the result of anthropogenic factors. Agriculture, now affecting c. 80% of Britain's surface, is overwhelmingly the most important such factor. Original vegetation had been mostly destroyed or heavily modified by a.d. 1700, notably through removal of the former forest cover and draining of lowland wetlands. The last 300 years have seen continuing development of farming and other land uses, to the point where very little natural vegetation now remains, and the main extent of semi-natural types is located in the uplands. Many distinctive semi-natural vegetation types actually created by man over several centuries of low input-low output management have decreased greatly since A.D. 1700, and rate of loss has even accelerated since 1940-1950. Only 5% of permanent lowland grasslands now remain agriculturally unimproved neutral grassland and only an estimated 20% of the extent of pre-1940 calcareous grassland is now assignable to that category floristically. Lowland acidic heath has declined by 78% in area since A.D. 1830, and by 40% of the 1950 level. Lowland rich fens are reduced to scattered remnants, the largest expanse (the East Anglian Fenland) having decreased from 3380 km2 in ad 1630 to 10 km2 in 1984. Forest cover was reduced to 5·4% by 1924, but has increased to 9·4%, largely through planting of alien conifers in upland districts. Since 1930 an overall 46 % of ancient semi-natural broadleaved woodland has been lost, largely by conversion to conifer plantation but also through grubbing out. An estimated 300000 ha of ancient semi-natural woodland remains, representing 14% of existing woodland and 1·3% of Britain's land surface. The total extent of hedges in England and Wales was reduced by an estimated 140000 miles (28%) between 1946-1947 and 1974. Urban-industrial growth, including roads, railways, water-use, mineral extraction and energy generation, has directly obliterated large areas of vegetation and caused chemical pollution. Waste ground associated with these activities often develops semi-natural plant communities through spontaneous succession, and may become floristically rich. Pollution affects especially fresh water through both toxic residues and eutrophication from nutrient enrichment (including run-off of agricultural fertilizers). Atmospheric pollution causes acid deposition especially damaging locally to the lichen flora, and induces biological changes in lakes and rivers in districts of acidic rocks. Recreational pressures have caused increasing disturbance to vegetation locally, and less directly through working of Sphagnum bogs for horticultural moss litter and surface mining of limestone pavements for rockery stone. Collecting of plants as a hobby has also brought some species, notably rare ferns, orchids and'alpines'to dangerously low population levels, or even local extinction. The British flora has been profoundly modified by human influence. Only 19 vascular species are known to have become extinct, but many have declined greatly during the last 300 years and, for species in some habitats, especially semi-natural grasslands, rate of decrease has accelerated since 1940. Of 317 nationally rare species 117 (37%) have declined by at least 33 % since 1930. Human agency has also introduced to Britain at least 239 plant species which now grow wild, and extended the distribution of at least 363 others. Some are still increasing but others, notably weeds of arable land, are decreasing again. Conservation measures include setting up nature reserves to contain adequate representation of all semi-natural and natural vegetation types, and of populations of all native plant species. The aim is to give protected area status to c. 10% of Britain's surface through appropriate control and management designed to maintain or enhance the nature conservation interest. At present c. 1% is managed as nature reserve of one or other category and another 6% has been designated as Sites of Special Scientific Interest. Wild plants are now legally protected against unauthorized picking and uprooting, and 61 rare species are protected by special measures. Wider environmental conservation measures to reduce damaging human impact on vegetation and flora include inputs to and by local authorities and their planning system, persuasion of landowners and resource managers, and pollution control; supported by an educational and publicity programme, and by relevant research and information.

ESTIMATING AERIAL BIOMASS IN SEMI-NATURAL VEGETATION FROM SPECTRAL REFLECTANCE MEASUREMENTS 1. PRELIMINARY EXPERIENCES

SUMMARY A technique of calculating aerial green biomass from spectral measurements in the red and near infrared bands is increasingly being applied in vegetation studies. It is fast, non-destructive and can be directly applied from aircraft or satellite mounted sensors to large areas. Literature data illustrating the potential of the approach refer sofar generally to rather ideal situations in low, open, herbaceous vegetation. Before general application can be recommended a body of reference including various situations should be available. The present contribution indicates some disturbing factors such as the presence of flowers or shade and evaluates the applicability of the technique for a number of vegetation types. Results of tests in 11 semi-natural vegetation types are presented, ranging in height from 30–150 cm and in cover from 20–100%. Measurements were made with – as later appeared – non-optimal equipment and no correction could be made for variation in incoming radiation. Multiple sampling at three to five dates between April and July resulted in correlation coefficient values of 0.96, 0.95, 0.92, 0.91, 0.91, 0.88, 0.85, 0.82, 0.67, and -0.06 (in the last case Holcus lanatus dominant) for aerial biomass dry and the IR/R ratio. These relatively high values are critically examined. The data provide evidence for a rather general applicability of the technique, but also for a cautios approach and a mandatory calibration per (floristically and/or physiognomically) different vegetation type.

An assessment of the nature conservation value of Majorca

In spite of increasing numbers of tourists each year, Majorca retains a variety of natural and semi-natural vegetation types. These are principally in the limestone sierra and around the coast. Of the fairly numerous species of endemic plants which occur, some are frequent. The Balearic Islands are also an important staging-post for migrant birds, and the wetlands of Majorca are the most valuable habitat from the ornithological standpoint. This paper summarizes the major vegetation types of Majorca and discusses the contribution made to the conservation value of the island by its 21 species of vascular plants that are recognized as endemic to the Balearic Islands and in 13 cases are exclusively Mallorcan. Finally, the conservation threats arising from urbanization, from indirect effects of development, and from changes in agricultural practice, are briefly discussed.