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The Balkan populations of the European wildcat are among the least studied. This study reports the first findings on the spatial ecology and activity pattern of the wildcat in Greece and compares them to those of better studied northern populations. We fitted five wildcats (two males, three females) with collars containing GPS and accelerometer loggers (E-obs 1A) and collected data from fall to early summer. All animals moved within a mosaic of lowland agricultural fields, woodland patches, riparian forests and wetlands near the banks of a lake. The trapping rate was the highest reported for the species. The home range sizes, estimated using Brownian bridge movement models, ranged from 0.94 to 3.08 km2 for females and from 1.22 to 4.43 km2 for males. Based on overall dynamic body acceleration (ODBA) values estimated from the accelerometer data, the diel activity of male wildcats followed the species’ typical nocturnal pattern with crepuscular peaks. Female activity varied seasonally, at times being cathemeral. We found only weak effects of environmental variables on wildcat activity, and no significant difference in the activity in open versus forested areas. Our findings suggest that human modified landscapes can play a significant role in the conservation of this typically forest-associated species.

The main goal of the present study was to evaluate the hexanoic acid (HEX) and acetic acid (ACET), two active ingredients of the nematicidal Melia azedarach fruits water extract (MWE), for use on root knot nematodes control. We studied the effect of the acids on various growth stages of the phytoparasitic nematode Meloidogyne javanica, along with the phytotoxicity on tomato plants, their fate in soil and ecotoxicology, including non-target soil nematode and microbial communities. The EC50/4d values established for paralysis activity on second-stage juveniles were 195 and 49 μg mL−1 for HEX and ACET, respectively. Both acids significantly inhibited M. javanica undifferentiated egg hatch and J2 release from free eggs immersed in 100 μg mL−1 solutions, but only HEX achieved activity when egg masses were treated with acids’ concentrations greater than 50 μg mL−1. HEX lasted longer in soil than ACET did and yielded less females of M. javanica per gram of tomato root (EC50 = 112 mg kg−1). Other than efficacy, the two acids had a negative impact on the free-living nematode abundances compared to the control, thus implying an eco-toxic character. MWE is effective for the target nematodes and increases the abundance of free-living nematodes and the microbial biomass.

Nematodes represent an important group of animals in the decomposer food web, because of high diversities, abundances and functional roles supporting ecological processes, such as decomposition. They have been relatively well studied in numerous ecosystems, but have rather skipped attention in sea turtle nests at sandy shores, where a massive supply of nutrients is taking place after turtle egg hatching. Being excellent indicators of ecological functioning, we hypothesized that nematode community characteristics could be indicative of the ecological/functional state of sea turtle nests as affected by hatching characteristics (e.g. number of eggs, hatching success rate etc.). In our study, conducted in Zakynthos (Greece), we perform a pioneer in-depth analyses of nematode communities in Caretta caretta nests after egg hatching. We further explore whether turtle reproductive success, measured through a number of metrics reflecting stages and portion of alive/dead hatchlings, are linked to nematode community characteristics. We found 14 different nematode genera in total. Our analyses demonstrate that nematodes play a critical role in functionality and energy flow in sandy shore ecosystems and that sea turtle nests present an ephemeral micro-habitat hosting communities with specific characteristics. These include rather high nematode abundances and communities in early successional stages with a simple trophic structure, almost exclusively dominated by bacterivore nematodes (mostly opportunistic/c-p 1) and without top-down control. Variables either showing success or failure of hatching explained a large amount of variability of nematode community characteristics, supporting our hypothesis. The nematode Metabolic Footprint was strongly associated with the amount of dead hatchlings concentrated in the turtle nest. Nematode taxonomic diversity and richness were closely associated with an increased hatching success rate at nest level. Our findings can offer a base for developing a framework for comprehensive and standardized assessments of sea turtle nests that could ensure comparability of results over spatial or temporal scales in monitoring projects. Further research might show how increased diversity of nematode communities could be achieved so to improve reproduction output and success of loggerhead sea turtles.

In recent years, interest has surged in the development of plant extracts into botanical nematicides as ecofriendly plant protection products. Aromatic plants are maybe the most studied category of botanicals used in this direction and the yielding essential oils are obtained on a commodity scale by hydro distillation. Nevertheless, can the bioactivity of aromatic plants always be attributed to the terpenes content? What would it mean for soil microcosms to bear the treatment of an essential oil to cure against Meloidogyne sp.? Are there other extraction procedures to prepare more ecofriendly botanical products starting from an aromatic material? Lemon thyme is studied herein for the first time for its nematicidal potential. We compare the efficacy of lemon thyme powder, macerate, water extract and essential oil to control Meloidogyne incognita (Chitwood) and Meloidogyne javanica (Chitwood), and we additionally study the secondary effects on soil microbes and free-living nematodes, as well as on tomato plant growth. According to our results lemon thyme powder enhances tomato plants&rsquo, growth in a dose-response manner and when it is incorporated in soil at 1 g kg&minus, 1, it exhibits nematicidal activity at a 95% level on M. incognita. The water extract yielding from the same dose is nematicidal only if it is left unfiltered, otherwise only a paralysis effect is demonstrated but inside the soil the biological cycle of the pest is not arrested. The essential oil is good both in performing paralysis and biological cycle arrest, but it detrimentally lowers abundances of bacterial and fungal feeding nematodes. On the contrary, lemon thyme powder and unfiltered water extract augments the bacterial biomass, while the latter also increases the bacterivorous nematodes. Overall, the bio fertilizing lemon thyme powder and its unfiltered water extract successfully control root knot nematodes and are beneficial to soil microbes and saprophytic nematodes.

Nematode communities are valuable bioindicators of soil disturbance induced by agricultural practices. We report the results of a short term experiment set on a field previously cultivated with shell beans, where different agricultural practices were applied, namely disinfection with chemicals or organic alternatives (neem, basil, marigold and clove oils). We provide a detailed description of the soil nematode community before and after the application of agricultural practices, in terms of trophic structure, nematode functional indices and diversity. We also employ network analysis techniques to analyze the structure of nematode assemblages on the basis of co-occurrence of genera in samples. Chemical disinfection had a direct lethal effect on all nematode genera reducing or even eliminating their populations, while organic amendments favored only the free living nematodes without affecting plant feeders. These differences were poorly reflected on changes of diversity and even less on those of nematode indices. Network analysis offered significant insights into the structural changes in the web of interactions among nematode genera. The network after chemical disinfection was smaller, poorly connected and almost entirely dependent on the dominant phytoparasite Paratylenchus. In the absence of chemicals, large and more complex networks were formed.

Anthropogenic pressures that involve different kinds of inflows (chemical vs organic) to soils are likely to induce different responses of individual soil components as well as to affect the web of interactions between them. The aim of this paper was to explore whether chemical or organic disinfection constitute two different types of disturbance, regarding both their severity on individual soil components and the structural changes they induce on the network of interactions among soil biochemical variables and nematode functional guilds. Network analysis, a novel approach in the context of soil ecology, was used to explore these interactions. Different plots within a field cultivated conventionally with Phaseolus vulgaris for many years were disinfected either with metham sodium or with a mixture of plant-based alternatives (neem and essential oils). Control plots receiving no disinfectants were also included in our study. One month after the treatments were applied, we estimated microbial C and N, activities of asparaginase, glutaminase, urease and phosphatase, organic C and N, inorganic N and P as well as the functional diversity of nematodes. Chemical disinfection had a direct lethal effect on all nematodes, while the effect on the microbial community was less obvious, implying that at the time of sampling, microbial populations, especially bacterial ones had started to recover from disturbance. Urease and phosphatase activities were inhibited, which may partly be responsible for the reduced amounts of inorganic N and P. Organic disinfectants reduced microbial populations, mainly the fungal ones, but they did not inhibit enzyme activities. The availability of N and P increased and nematode abundance was not affected significantly. The results demonstrate the usefulness of network analysis in providing insight into the structure and robustness of the soil network and its response to disturbance. Despite the pronounced reduction in nematode numbers due to chemical disinfection, the importance of nematode guilds within the interaction network was amplified and a more compact network was formed. On the other hand, interactions within organic plots were found to be primarily dictated by soil biochemistry. Finally, the analysis showed that both types of disinfection increased the vulnerability of the interaction network and this was more pronounced in chemically treated plots.

The aim of this study was to assess the seasonal development of the physicochemical (pH, organic C, organic N, extractable P, Ca(2+), Mg(2+)) and biological soil properties (microbial biomass, activities of urease, dehydrogenase and alkaline phosphatase) of the topsoil of mine deposition sites that differed based on the material used exclusively for their creation: (a) marlstones, (b) red-grey formations (RGF), and (c) fly ash (FA), during the first year after their creation. Our hypothesis was that all deposition sites, regardless the material they consist of, present equal opportunities for the establishment of spontaneous vegetation. All macronutrients concentrations (P, Ca(2+), and Mg(2+)) remained constant with time and were found to be higher in the FA sites. Organic C, organic N, all enzyme activities, and microbial biomass were higher in the RGF and marl depositions, with marl sites presenting the highest values. All values of biological variables, with the exception of alkaline phosphatase, increased with time. The alkaline environment along with the slow improvement in soil biological properties of the FA sites seemed to present the most unfavorable conditions for spontaneous vegetation growth. On the contrary, the other two spoil materials presented significant improvement in the initial stages of soil formation in terms of soil functionality.

Abiotic and biotic components of a serpentine Mediterranean soil were studied in terms of heavy metal and nutrient concentrations, microbial biomass, and structural and functional characteristics of the soil nematode community. We explored differentiations of the soil environment imposed by vegetation, sampling the bare soil and soil under Buxus sempervirens, Juniperus oxycedrus, Cistus creticus and Thymus sibthorpii. Organic matter, microbial biomass, nutrient availability and calcium/magnesium (Ca/Mg) ratio of the serpentine site were similar to those of degraded, non-serpentine Mediterranean ecosystems; the serpentine site showed potassium deficiency and high heavy metal load. Soil nematode abundance, especially of phytoparasites, was very low. Low enrichment and structure indices and high channel index values indicated a degraded, low-resource, stressful environment where fungal decomposition predominates. There was no differentiation of heavy metal concentrations among microsites. Bare soil exhibited high pH, low water content, low Ca/Mg (0.68), low nutrient concentrations, low abundance of most nematode groups, low values of maturity and plant parasitic indices, low nematode diversity and a distinct generic composition. Rhizosphere soil was differentiated according to the evergreen–sclerophyllous or seasonal–dimorphic habit of shrubs. This was reflected in soil nutrients and in all parameters of the soil nematode community.