Description: The measurement of heavy metal concentrations in plants is important both for determining their ability to remove these pollutants from the air to increase its quality, and for the monitoring of air quality. Previous studies have mostly focused on the use of annual leaves of broadleaved species as biomonitors. In this study, the aim was to determine the heavy metal accumulation of the perennial needles of some conifers. In almost all the species studied, concentrations of heavy metals were found to increase with the age of the tree, but this increase was not linear. There were significant differences between the species in terms of heavy metal accumulation. The highest concentrations were for Fe in Pinus nigra , Zn in Picea pungens , Pb in Pinus sylvestris , and for all the other heavy metals in Abies bornmülleriana . This study indicates that A. bornmülleriana is particularly useful as a biomonitor for many heavy metals, and also has the potential to remove heavy metals from the air.

Description: The Great East Japan Earthquake that occurred on 11 March 2011 generated a series of massive tsunami waves that caused severe damage to the Fukushima Daiichi Nuclear Power Plant, following which large amounts of radioactive materials were discharged from the power plant into the environment. Given the recently developed technologies for unmanned helicopters and their potential application in airborne radiation monitoring, we developed a radiation monitoring system for aerial use. We then used unmanned helicopters to measure the radiation level in areas with soil contaminated by radiocesium emitted from the nuclear power plant to evaluate the ambient dose rate distribution around the site. We found that in dry riverbeds downstream of the highly contaminated watershed, especially in the upstream parts, that the ambient dose rate was higher than that in protected inland areas. In addition, we carried out soil sampling in dry riverbeds. The soil sample data agreed with the results obtained from the unmanned helicopter. A possible scenario is that river sediment and adjacent soil containing radioactive materials were carried downstream due to an event such as a rise in water level caused by, e.g., a typhoon, and that these remained in the riverbed after the water drained away. The vertical profile of radiocesium in the soil and the measurements of river sediment at river mouth areas corroborated this scenario.

Description: Anthropization of forest landscapes is a major threat to ecosystems and biodiversity. To gather comprehensive information on anthropization dynamics in forest landscapes, fine-scale surveys of deforestation are required, coupled with detailed analysis of both spatial transformation processes and forest patch geometry. We conducted such a comprehensive study in a monospecific Uapaca bojeri (Baill.) forest of Madagascar, between 1999 and 2013. A diachronic set of four maps was produced and deforestation rates were calculated. Spatial transformation processes were described using Bogaert et al. (2004) typology. Forest patch geometry was monitored using largest patch index, mean patch size, and squared mean patch size to describe patch size dynamics, mean shape index and area weighted mean shape index to describe patch compactness, and fractal dimension analysis to describe patch outline complexity. For fractal dimension analysis, an innovative segmented regression model (Muggeo 2008 ) was used to separately quantify fractal dimensions for multiple ranges of patch sizes. Our results showed a growing anthropization of the U. bojeri forest landscape in the area, through a strong yet decelerating deforestation (from − 59.5% year −1 between 1999 and 2005 to − 2.84% year −1 between 2009 and 2013), clear forest fragmentation, and a subtle yet growing-in-scale simplification of patch geometry for small forest patches. Deforestation was artisanal in nature and, in 2013, large patches were withdrawing to less accessible topographic features. Our results forecast a medium-term loss of resilience of the U. bojeri forest in the area, if no direct forest conservation measures are taken.

Description: For high-density urban environments, improving local landscapes can effectively ameliorate the thermal environment. With the aim of assessing the effect of landscape characteristics on thermal performance in open spaces of residential areas, we took field measurements using mobile traverses in 18 residential areas of Beijing, China during the daytime in summer (June–August 2014) and winter (December 2014–February 2015). The net differences (d) of air (dATs) and radiation temperature (dRTs) between residential and nearby corresponding urban open environments, regarded as indicators of the thermoregulation of the 18 residential areas, were calculated. The effects and relative contributions of different landscape characteristics to the indicators were further investigated. Within residential areas, there were overall lower ATs and RTs compared with the control sites in open urban environments. The maximum and minimum dAT and dRT ranged from 0.53 to 6.14 °C and 3.16 to 8.65 °C in summer, and from −0.50 to 1.25 °C and −0.84 to 4.01 °C in winter, respectively. The net dATs and dRTs were significantly different among the 18 residential areas. An increasing percentage of vegetation cover and arbor-shrub planting density and decreasing percentage of pavement area, percentage of building cover and distance to downtown had varying degrees of favorable effects on dAT and dRT. In contrast, average building height had a slight seasonally opposite regulating impact. Compared with dAT, the net dRT is more sensitive to changes in landscape characteristics. The relative contribution of different landscape parameters to explaining the differences in the two types of temperature differed and varied by season. The percentages of pavement area and vegetation cover played the most important roles in summer and winter. If appropriately combined, local landscape characteristics could effectively ameliorate local thermal environments.

Description: This study examined 137 Cs detachment from needle litter of Japanese cedar ( Cryptomeria japonica ) through leaching and decomposition in a headwater stream located 45 km from Fukushima Daiichi Nuclear Power Plant. We placed litter bags in pools and riffles and removed them after 4, 15, 75, 150, and 240 days. The 137 Cs activity concentration in litter collected after 4 and 15 days was 48–72 % of the initial 137 Cs activity concentration in litter. The 137 Cs activity concentration in litter after 240 days in the pools decreased by 26 %, while that in litter of riffles decreased by 9 % compared with the initial 137 Cs activity concentration. The dry weight of litter became 71 and 86 % of initial weight after 75 days, and from 32 to 51 % after 150 days. The decay coefficient of litter ( k  = 0.0060) in the riffles was 1.6-fold higher than that in the pools ( k  = 0.0037). The greater decrease in litter weight with longer submergence time was possibly associated with a combination of leaching and decomposition, in particular in litter that was submerged for 100 days in the water column. The difference in the rate of decomposition and 137 Cs detachment from litter between the riffles and pools was due to the substrate and flow conditions at the litter bag sites. Examining the different patterns of 137 Cs detachment from litter among channel morphologies is necessary for comprehending the mechanisms of 137 Cs accumulation in aquatic biota. The findings of this study suggest that elucidating leaching and decomposition processes in litter of stream channels is important for understanding 137 Cs dynamics in forested headwater ecosystems.

Description: We surveyed plant species composition and distribution in the Tottori Sand Dunes, a strictly protected large coastal dune area of western Japan. We aimed to determine the percentage of species of regional coastal flora that can be maintained, and the relationship between plant species diversity and habitat type, in a large coastal dune reserve. In the Tottori Sand Dunes, we identified 132 vascular plant species, including four endangered species and 20 coastal species. We recorded 36% of Tottori Prefecture’s coastal plants here, suggesting that a protected large coastal dune area that stands alone cannot provide a habitat for all the coastal plant flora at a regional scale. A greater number of coastal plant species were found in the seaside habitat, and it appears that plants more resistant to salt spray and wave action survive there. No plant habitats were found in the main tourist area, which may be a consequence of trampling. The highest number of species was found in the rear dune hollow habitat, whereas that of alien plants was found in the dune hollow habitat. In the dune hollow habitat, weeding during summer may have encouraged the annual invasion of alien plants. This study has shown that plant species diversity is affected by a variety of dune dynamics and also by human impact.

Description: Grassland restoration is a key measure for re-establishing damaged floral communities. As seed banks are often degraded, methods are needed to overcome dispersal limitation of the remnant vegetation. One approach is to vacuum harvest seeds from donor sites. While this is a cost-effective method, individual species’ traits describing reproduction methods and dispersal mechanisms may affect the success with which seeds are collected and subsequently germinate. We collected seeds using low-cost vacuum harvesters in species-rich meadows in Poland. We predicted the relative success with which seedlings emerged from this collected material with respect to their percentage cover in the donor sites on the basis of individual species’ functional traits. Prolific species that rely on seed as opposed to vegetative reproduction, and those that germinate in late summer/autumn, exhibited the highest level of emergence. To a lesser extent, drought-tolerant or shade-intolerant species were well represented in the collected material. There was also weak evidence that wind-dispersed seeds would have a higher likelihood of being collected by this method. Our results suggest that vacuum harvesting is a valuable method to collect seeds for use in grassland restoration; however, it has limitations. In particular, additional methods may be needed to introduce into grassland restoration sites the propagules of species that vegetatively reproduce or seed early. The overrepresentation of species that produce large numbers of seed may potentially introduce priority effects that could also have unintended long-term implications for the structure of the floral community.

Description: We examined the cesium-137 ( 137 Cs) contamination of river food webs in a gradient of initial fallout deposition (net density estimates 2.5–3.5 months after the Fukushima Daiichi Nuclear Power Plant accident in March 2011), in Fukushima Prefecture, Japan. Litter, aquatic insects, and salmonid fish were collected in five headwater stream reaches (watershed-average fallout density, 368.1–1398.4 kBq/m 2 ) for the measurement of 137 Cs concentration and stable isotope ratios of carbon (δ 13 C) and nitrogen (δ 15 N) in June 2014. The stable isotope ratios suggested that the detrital food chain was a dominant energy pathway in rivers originating from a basal resource (litter) to primary (aquatic insects) and secondary (fish) consumers. The 137 Cs concentration decreased with an increase in the trophic level, with the highest value for litter (10930 ± 5381 Bq/kg, mean ± SD), the lowest for fish (2825 ± 2451 Bq/kg), and the intermediate one for dominant (numerically and biomass-wise) detritivorous insect, Ephemera japonica McLachlan (4605 ± 1970 Bq/kg). 137 Cs concentrations of three trophic levels were linearly predicted by the initial fallout amount of 137 Cs. The evacuation of the gut contents of E. japonica during field experiments led to a reduction in their 137 Cs concentration by approximately 50% within 1–2 day(s) without loss of body weight. This suggested that a substantial portion of 137 Cs contamination of E. japonica was derived from highly contaminated fine solids deposited in depositional habitats at a disproportionately high density. Overall, the initial fallout amount of 137 Cs was helpful in roughly predicting the contamination levels of headwater river-riparian ecosystems with the detrital food chain as a dominant energy pathway. Long-term monitoring of the dynamics and fates of 137 Cs associated with fine organic and inorganic particulates appears important for better prediction of 137 Cs contamination of food webs in forested headwater streams.

Description: In Morocco, sacred groves called marabouts constitute a dense network of wild-forest remnants of high ecological and cultural value but which are threatened by global change. In this study, we investigated the relationship between sacred natural site (SNS) structure and landscape dynamics in the traditional Mediterranean landscape of the Beni Arouss tribe in Northern Morocco. The total number of sacred sites considered was 101, with an average density of 3 SNSs per 10 km 2 and an average area of 2.73 ha per SNS covered with natural vegetation—mainly cork oak forests ( Quercus suber ), woodlands ( Quercus coccifera , Olea europaea ), and scrublands. Analysis of the vascular plants in these sacred groves showed that there were 73 natural species and 3 fruit species in total; the natural species belonged to four plant forms: 6 tree species, 10 liana species, 20 shrub species, and 37 herbaceous plant species. To investigate the relationships between sacred groves and landscape change, the territory was divided into 51 land-use clusters around rural settlements. Multivariate analysis permitted the identification of three types of clusters categorized according to social-ecological system (SES): forest (F), agro-forest (AF), and agriculture (A). The landscape dynamics over the period from 1986 to 2003 were investigated, and those dynamics were found to be dominated by the conversion of forest to agriculture, which resulted in the transformation of 25% of the SESs from F-SESs and AF-SESs into A-SESs during the period considered. Statistical comparisons of plant forms in sacred groves belonging to stable SESs during the period 1986–2003 showed that tree richness and liana cover were higher in F-SESs than in A-SESs, shrub richness and cover were higher in AF-SESs than in A-SESs, but there were no plant forms differences between F-SESs and AF-SESs. We argue that SES transformation processes—as represented by spatial dynamics—involve a regression of sacred groves, such that the functional plant groups of sacred groves could be considered ecological indicators.

Description: The evaluation of the success of soil bioengineering work is an issue still poorly addressed by the scientific community. Nevertheless, soil bioengineering techniques are increasingly used worldwide when mitigating the impact on the environment and the landscape is one, but not the only, goal of intervention. A tool to measure the success of soil bioengineering work, with reference to landslide stabilization, is presented in this paper: the index of ecological success (IES). The IES is based on the phytosociological analysis of vegetation and widens the potential applications of the ecological index of maturity (EIM), recently formulated by Giupponi et al. (Restor Ecol 23:635–644, 2015) to assess the degree of disturbance affecting a plant community. The IES compares the EIM values of the vegetation of an area affected by soil stabilization work with those of the expected vegetation at a precise time after completion of soil stabilization work, providing values ranging between 0 (maximum failure) and 1 (complete success). The IES was applied in two study areas located on two mountain slopes of the Southern Alps (Italy) which, as a result of landslides, were subject to soil bioengineering work aimed at slope stabilization. The results of these first two applications confirm the efficacy of the IES in evaluating the success of soil bioengineering work in mountain areas and bode well as to its future application.