Night irradiance and synchronization of lunar release of planula larvae in the reef coral Pocillopora damicornis

Pocillopora damicornis (Linnaeus), which is known to release planula larvae on a monthly cycle, was grown in full daytime solar irradiance, but with four treatments of night irradiance: (1) natural night irradiance, (2) shifted-phase (total darkness during nights of full moon with artificial irradiance at lunar intensity on nights of new moon), (3) constant full moon (full lunar irradiance every night), and (4) constant new moon (total darkness every night). The reproductive cycle of the corals held in the shifted-phase treatment moved out of synchrony with the cycle of corals exposed to a natural lunar cycle of night irradiance. Two previously described types of P. damicornis were tested. The Type Y normally start releasing larvae at full moon, with peak production at third quarter. In the shifted-phase treatment they began releasing planulae at new moon (artificial full moon), with peak production at first quarter. The Type B corals, that normally start releasing planulae at new moon with peak production at first quarter, began to release planulae at full moon (artificial new moon), with peak production at third quarter. Populations of corals grown either in the constant full moon or constant new moon treatment quickly lost synchronization of monthly larva production, although production of planulae continued. Thus spawning is synchronized by night irradiance.Contribution No. 702 of the Hawaii Institute of Marine Biology     

Energetics,competency, and long-distance dispersal of planula larvae of the coral Pocillopora damicornis

Pocillopora damicornis (Linnaeus) were collected from Enewetak Atoll, Marshall Islands, in 1980–1981) and Kaneohe Bay, Hawaii, in 1982. Their planula larvae contained 17% protein, 70% lipid, and 13% carbohydrate by dry weight. Calculations based on stored energy reserves and daily metabolic expenditure indicate that planulae could survive approximately 100 d and still settle successfully. Competency experiments demonstrated that larvae settled and metamorphosed after 103 d. This period of time is sufficient to allow immigration of larvae from the Central Pacific to the eastern Pacific, and supports the hypothesis of long-distance dispersal of larvae for the origin of present eastern Pacific populations of P. damicornis.     

Differential meiospore size and tolerance of ultraviolet light stress within and among kelp species along a depth gradient

 Kelp are differentially stratified along a gradient of UV exposure (as a function of water depth). The role of ultraviolet light in seaweed zonation has not been fully explored. This study found a significant meiospore size difference within and among the kelp species examined: Pterygophora californica Ruprecht (high to mid-subtidal), Macrocystis integrifolia Bory (high to mid-subtidal), Laminaria groenlandica Rosenvinge (high-subtidal), Alaria marginata Postels and Ruprecht (low-intertidal) and Hedophyllum sessile Setchell (mid-intertidal). This size difference was correlated with the depth distribution of adult plants, with the largest meiospores originating from shallow-dwelling adult kelp exposed to high UV light. Under UV stress in the laboratory, meiospores from adults growing in high-UV environments displayed greater germination and survival rates than the progeny of adult kelp occupying lower-UV environments. This suggested that in Barkley Sound, British Columbia, Canada, differential tolerance to UV (possibly determined by meiospore size) may limit the upper settlement position of kelp species and individuals. Tolerance to UV may be an important determinant of kelp zonation on rocky shores. Received: 16 June 1998 / Accepted: 6 January 2000     

A multi-locus genetic assignment technique to assess sources of <Emphasis Type="Italic">Agaricia agaricites</Emphasis> larvae on coral reefs

Assignment of individuals to populations based upon genetic data is an important ecological problem that requires many polymorphic markers, often more than are available using single locus techniques. To demonstrate the utility of amplified fragment length polymorphisms (AFLP) in studying larval dispersal and recruitment in coral populations, two sets of AFLP primers were used to genotype colonies of the coral Agaricia agaricites Linnaeus from three widely separated geographic locations: the Bahamas (23°28′N, 75°42′W) and Key Largo, Florida (24°55′N, 80°31′W—two sites separated by 12 km) in 1995, and the Flower Garden Banks (FGB) in the Gulf of Mexico (27°55′N,93°36′W) in 1997. In addition to adult samples from each site, recruits were collected from settling plates placed on the East FGB for 1 year (1997–1998). The AFLP technique yielded 45 polymorphic markers. An analysis of molecular variance (AMOVA) showed significant genetic differences among the four adult populations, even between the two Key Largo sites. The recruits were significantly different from all adult populations except those from the FGB. Discriminant function analysis and the program AFLPOP were used to assign individuals to populations. Using the adult AFLP-banding patterns to build the statistical models, both procedures correctly assigned the majority of adults to their respective populations in simulations and assigned all but one of the recruits to the Flower Garden population from where they were collected . The AFLP technique provides a simple and adaptable population assignment method for studying recruitment processes in A. agaricites and other coral species. Electronic Supplementary Material Supplementary material is available for this article at     

Feeding behavior and acquisition of zooxanthellae by planula larvae of the sea anemone Anthopleura elegantissima

Symbiotic associations between cnidarians and photosynthetic dinoflagellates (i.e., zooxanthellae) are common in the marine environment. Many symbiotic cnidarians produce offspring that are initially nonsymbiotic. These new hosts must acquire symbiotic algae from environmental sources. We examined zooxanthella acquisition by laboratory-reared planula larvae of the temperate sea anemone Anthopleura elegantissima. Larvae ingested zooxanthellae while they were feeding. However, the signal that prompted larval feeding behavior did not originate from the symbiotic algae; the addition of algal cells to larval cultures never elicited a feeding response. In contrast, the addition of macerated animal tissue from several sources invariably generated a strong feeding response, which resulted in the larvae indiscriminately ingesting any particulate matter that was present, including zooxanthellae or other unicellular algae. Ingested zooxanthellae were incorporated into endodermal cells, where they remained undigested, while all other ingested material was digested or expelled within 24 h. Our results provide evidence that one source of zooxanthellae likely to serve as a route of infection in the natural environment is zooxanthella-laden mucus egested by anemones. This egested material fulfilled both of the criteria necessary for successful infection: it prompted larvae to begin feeding and provided an abundant supply of zooxanthellae that were ingested and taken up into endodermal cells of the new host.     

Antipredator defenses along a latitudinal gradient in Rana temporaria

Antipredator defenses are expected to decrease toward higher latitudes because predation rates are predicted to decrease with latitude. However, latitudinal variation in predator avoidance and defense mechanisms has seldom been studied. We studied tadpole antipredator defenses in seven Rana temporaria populations collected along a 1500-km latitudinal gradient across Sweden, along which previous studies have found increasing tadpole growth and development rates. In a laboratory common garden experiment, we measured behavioral and morphological defenses by raising tadpoles in the presence and absence of a predator (Aeshna dragonfly larva) in two temperature treatments. We also estimated tadpole survival in the presence of free-ranging predators and compared predator densities between R. temporaria breeding ponds situated at low and high latitudes. Activity and foraging were generally positively correlated with latitude in the common garden experiment. While all populations responded to predator presence by decreasing activity and foraging, high-latitude populations maintained higher activity levels in the presence of the predator. All populations exhibited defensive morphology in body and tail shape. However, whereas tail depth tended to increase with latitude in the presence of predator, it did not change with latitude in the absence of the predator. Predator presence generally increased larval period and decreased growth rate. In the southern populations, predator presence tended to have a negative effect on metamorphic size, whereas in the northern populations predators had little or a positive effect on size. Latitude of origin had a strong effect on survival in the presence of a free-ranging predator, with high-latitude tadpoles experiencing higher mortality than those from the low latitudes. In the wild, predator densities were significantly lower in high-latitude than in mid-latitude breeding ponds. Although the higher activity level in the northern populations seems to confer a significant survival disadvantage under predation risk, it is probably needed to maintain the high growth and development rates. However, the occurrence of R. temporaria at high latitudes may be facilitated by the lower predator densities in the north.     

Substratum preferences in planula larvae of two species of scleractinian corals, Goniastrea retiformis and Stylaraea punctata

To test whether coral planulae recruit randomly to different coral reef habitats or have specific substratum preferences, the settling behavior of planulae from two shallow water coral species from Pago Bay, Guam (13°25.02N, 144°47.30E) were examined in the laboratory in June and July of 1995. Goniastrea retiformis is generally restricted to the shallow reef front (<10 m depth) in areas dominated by crustose coralline algae (CCA), while Stylaraea punctata is abundant on inner reef flats were CCA coverage is low and sand and carbonate rubble covered by biofilms is common. When presented with four substrata (1) carbonate rock scrubbed free of biofilm and dried as a control, (2) the CCA Hydrolithon reinboldii, (3) the CCA Peyssonelia sp., and (4) naturally conditioned carbonate rubble covered by a biofilm, G. retiformis larvae showed a significant preference for H. reinboldii, and S. punctata larvae for the carbonate biofilm treatment. The preference shown by S. punctata larvae for biofilmed surfaces did not diminish with increasing larval age up to 11 days. These results suggest that the larvae of both species are capable of habitat selection, and that the preferred substrata among those tested bears a relationship to the habitats in which adult colonies were found. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Inversion of plant dominance-diversity relationships along a latitudinal stress gradient

Species interactions affect plant diversity through the net effects of competition and facilitation, with the latter more prevalent in physically stressful environments when plant cover ameliorates abiotic stress. One explanation for species loss in invader-dominated systems is a shift in the competition-facilitation balance, with competition intensifying in areas formerly structured by facilitation. We test this possibility with a 10-site prairie meta-experiment along a 500-km latitudinal stress gradient, quantifying the relationships among abiotic stress, exotic dominance, and native plant recruitment over five years. The latitudinal gradient is inversely correlated with abiotic stress, with lower latitudes more moisture- and nutrient-limited. We observed strong negative effects by invasive dominant grasses on plant establishment, but only in northern sites with lower-stress environments. At these locations, disturbance was critical for recruitment by reducing the suppressive dominant (invasive) canopy. In more stressful environments to the south, the impacts of the dominant invaders on plant establishment became facilitative, and diversity was more limited by seed availability. Disturbance prevented recruitment because seedling survival depended on a protective plant canopy, presumably because the canopy reduced temperature or moisture stress. Seed limitation was similarly prevalent in all sites. Our work confirms the importance of facilitation as an organizing process for plants in higher-stress environments, even with transformations of species composition and dominance. It also demonstrates that the mechanisms regulating diversity, including invader impacts, can vary within the same plant community depending on environmental context. Because limits on native plant recruitment are environmentally contingent, management strategies that seek to increase diversity, including invader eradication, must account for site-level variations in the balance between biotic and abiotic constraints.     

Vocal dialect and genetic subdivisions along a geographic gradient in the orange-tufted sunbird

At least four hypotheses have been suggested to explain the formation and maintenance of song dialects among birds: historic processes (epiphenomenon), genetic or local adaptation, acoustic adaptation, and social adaptation. We studied spatial and temporal distribution of dialect in the orange-tufted sunbird (Nectarinia osea), a small nectarivorous bird that expanded its breeding range in Israel during the past 100 years from the southern part of Rift Valley to the entire country. Sunbird range expansion was concurrent with the establishment of many small settlements with an ethos of gardening, which introduced many ornithophilous plants. We recorded songs and genetically screened individual sunbirds in 29 settlements distributed across a 380 km north–south gradient along the Rift Valley. We show that dialects cluster together into geographical regions in 70% of cases, a moderate concurrence to geography. Settlement establishment date, geographical position, and genetic distance between local populations (i.e., settlements) were all poor predictors for the variance among song dialects. The specific effect of habitat was not tested because all sampled localities were similar in their physical and acoustic properties. Using a network analysis, we show that dialects seem to aggregate into several network communities, which clustered settlement populations from several regions. Our results are best explained by either the epiphenomenon hypothesis or the social adaptation hypothesis, but at present our data cannot state unequivocally which of these hypotheses is better supported. Last, we discovered a negative association between network centrality and genetic diversity, a pattern that requires further examination in other systems.     

Breeding success of tree swallows along a gradient of agricultural intensification

The intensification of agricultural practices has been identified as the main cause of population decline in farmland birds since the 1960s in both Europe and North America. Although the links between species richness or abundance and various components of agricultural intensification are well established, the mechanisms underlying these trends have rarely been addressed along a gradient of intensification or have been quantified at only one spatial scale. Here we quantified the influence of landscape structure on the nest box occupancy and breeding success of Tree Swallows (Tachycineta bicolor) at seven spatial scales (1, 2, 3, 4, 5, 10, and 20 km radii) over a 10 200-km2 gradient of agricultural intensification in southern Québec, Canada. A network of 400 nest boxes distributed among 40 farms was visited every two days over three breeding seasons, 2004-2006. Nest box occupancy decreased with the proportion of intensive cultures (maize, cereals, and soybeans) in the landscape, especially when manure heaps and tanks were abundant, and was also determined by local variables (i.e., nest box clearance, interspecific competition) and by previous-year fledging success. Clutch size decreased as the breeding season progressed and with the proportion of intensive cultures in the landscape, with no consistent variation across spatial scales. Hatching success was not related to any landscape variables but increased with clutch size. Both the number of fledglings and fledging probability increased with the proportion of extensive cultures (hayfields, pastures, and fallows). These effects increased with spatial scale and reached a plateau at the 5 km radius: the maximum distance from the nest reached by foraging Tree Swallows. Our results can likely be attributed to lower food availability in intensive cultures compared to extensive ones. This study suggests that several components of breeding that impact on population structure and dynamics of insectivorous birds will be negatively affected by agricultural intensification.     

三江平原不同水位梯度湿地地上生物量动态特征

水分条件变化直接影响湿地植物群落的分布及其生产量,为了阐明不同水分条件湿地初级生产力的形成规律,揭示水文格局对湿地生态系统物质生产过程的调控机理,采用收获法研究了三江平原不同水位梯度上的小叶章(Calamagrostics angustifolia)、乌拉苔草(Carex meyeriana)和毛苔草(Carex lasiocarpa)湿地地上生物量的结构动态及其增长速率,结果表明:3类湿地地上及其各器官生物量均呈单峰型变化,小叶章湿地和乌拉苔草湿地地上生物量的峰值出现的时间早于毛苔草湿地,而且小叶章湿地和乌拉苔草湿地各季节地上生物量均大于毛苔草湿地.茎对小叶章湿地地上生物量的平均贡献率与毛苔草湿地相近,均大于乌拉苔草湿地;叶对小叶章湿地地上生物量的平均贡献率与毛苔草湿地相近,均小于乌拉苔草湿地.3类湿地地上生物量的绝对增长率和相对增长率的变化趋势基本相同,但不同阶段绝对增长率和相对增长率值的大小存在差异.3类湿地地上生物量及各组分生物量的季节动态变化均符合抛物线模型,并且各模型拟合精度均较高,R2基本都在0.92以上.     

Shifts in positive and negative plant interactions along a grazing intensity gradient

Isolating the single effects and net balance of negative and positive species effects in complex interaction networks is a necessary step for understanding community dynamics. Facilitation and competition have both been found to operate in harsh environments, but their relative strength may be predicted to change along gradients of herbivory. Moreover, facilitation effects through habitat amelioration and protection from herbivory may act together determining the outcome of neighborhood plant-plant interactions. We tested the hypothesis that grazing pressure alters the balance of positive and negative interactions between palatable and unpalatable species by increasing the strength of positive indirect effects mediated by associational resistance to herbivory. We conducted a two-year factorial experiment in which distance (i.e., spatial association) from the nearest unpalatable neighbor (Stipa speciosa) and root competition were manipulated for two palatable grasses (Poa ligularis and Bromus pictus), at three levels of sheep grazing (none, moderate, and high) in a Patagonian steppe community. We found that grazing shifted the effect of Stipa on both palatable grasses, from negative (competition) in the absence of grazing to positive (facilitation) under increasing herbivore pressure. In ungrazed sites, belowground competition was the dominant interaction, as shown by a significant reduction in performance of palatable grasses transplanted near to Stipa tussocks. In grazed sites, biomass of palatable plants was greater near than far from Stipa regardless of competition treatment. Proximity to Stipa reduced the amount of herbivory suffered by palatable grasses, an indirect effect that was stronger under moderate than under intense grazing. Our results demonstrate that facilitation, resulting mainly from protection against herbivory, is the overriding effect produced by unpalatable neighbors on palatable grasses in this rangeland community. This finding challenges the common view that abiotic stress amelioration should be the predominant type of facilitation in arid environments and highlights the role of herbivory in modulating complex neighborhood plant interactions in grazing systems.     

Diel patterns of abundance of presettlement reef fishes and pelagic larvae on a coral reef

Most presettlement reef fish settled at night at One Tree Island, Great Barrier Reef. Fish were sampled day and night using channel nets located on the reef crest, and a plankton-mesh purse-seine net in the lagoon (1992–1994). Catches of fish at night were generally tens to hundreds of times greater than those taken during the day. Preflexion fish, as well as postflexion and pelagic juveniles, were taken in greater numbers at night. Preflexion forms were a combination of those that had hatched from demersal eggs and later stages that had been transported over the reef crest. Highest numbers of postflexion and pelagic juvenile forms of Apogonidae, Blenniidae, Gobiesocidae, Gobiidae, Labridae, Lutjanidae, Mugiloididae, Mullidae, Pomacentridae, Scaridae, Serranidae and Tripterygiidae were found at night. Observations, while SCUBA diving, and purse-seine samples in the lagoon indicated that the only resident larvae were of the genera Spratelloides and Hypoatherina; most of the fishes caught in nets, therefore, were immigrants. Patch reefs, sampled for new settlers early in the morning and late in the day, indicated that the majority of apogonids (Apogon doederleini, >95%) settled at night. Although greater numbers of pomacentrids were found in morning counts (e.g. Pomacentrus wardi), if data were converted to an hourly rate, many pomacentrids showed a similar hourly rate of settlement day and night. Depth-stratified sampling in waters near One Tree Island (to 20 m) indicated that some taxa rise to the surface at night. This behaviour, perhaps combined with avoidance of diurnal predators may explain on-reef movement of potential settlers soon after dark. Studies on settlement cues, therefore, need to focus on night-related phenomena. Received: 3 March 2000 / Accepted: 20 June 2000     

Vallisneria natans decomposition rates and associated macroinvertebrates,microbes and microalgae along a vertical depth gradient in an urban lake (Nanhu Lake,China)

Knowledge on aquatic macrophyte decomposition has well developed, yet the decomposition and associated biotic factors along a vertical gradient in waters remain less examined. Here, we used Vallianeria natans leaves to investigate the decomposition rate and associated decomposers and microalgae at different vertical depths, by placing V. natans leaves into litterbags (0.5 and 5?mm meshes) and incubating them at the air–water interface (AW), sediment-water (SW) interface, and 10?cm (B10) or 20?cm (B20) burial in sediment over 60 days in a littoral zone of lake. Decomposition rates decreased with increased depths in each mesh size, with significant differences among and between AW (0.028?d^?1), SW (0.022?d^?1), B10 (0.014?d^?1) and B20 (0.011?d^?1) treatments in 0.5?mm litterbags and no significant difference between B10 (0.027?d^?1) and B20 (0.025?d^?1) in 5?mm litterbags. The average contribution of macroinvertebrates to biomass loss was highest in B20 (44.66%), lowest in AW (22.66%) and midst in both SW (25.35%) and B10 (38.78%), and was much less than that of both microbes and microalgae at each location. We show the importance of macroinvertebrates, microbes and microalgae in mediating macrophyte decomposition rate in response to different vertical locations in freshwaters.     

Variation in resource consumption across a gradient of increasing intra- and interspecific richness

Based on the premise that ecosystems with more species will function at more efficient rates, declining biodiversity is expected to alter important ecosystem functions, goods, and services across the globe. However, applicability of this general hypothesis to genetic or clonal richness in assemblages composed of few species is understudied. This illustrates the need to expand the focus of biodiversity-ecosystem-function experiments across all levels of biological diversity (including genetic). To explore this generality, we manipulated intraspecific (clonal) and interspecific (species) richness of a primary consumer, Daphnia, and measured assemblage feeding rate and total resource consumption. Our results showed that greater clonal richness had no effect on Daphnia feeding, and greater species richness decreased feeding-related effects of Daphnia. This suggests that multiclonal Daphnia assemblages may be no more efficient at consuming resources than monocultures, and that monocultures of Daphnia may consume resources more efficiently than more species-rich assemblages. The inhibitory effect of increasing richness observed in this study resulted from chemical and mechanical interference among some of the Daphnia taxa. This suggests that consumer-mediated ecosystem functions could be reduced when assemblages include taxa equipped with adaptations for interference competition.     

Variability in trophic dominance of crustaceans along a gradient of urban and industrial contamination

The trophic organization of the crustacean fauna belonging to a photophilic assemblage exposed to an urban and industrial contamination gradient in the Gulf of Fos (South of France) was studied over a period of 16 mo (May 1974 to August 1975). An increasing destabilization of the four major trophic groups from clean waters towards those most polluted was noted. Carnivores dominated at the relatively cleanwaterCystoseira stricta station; at the second, moderately pollutedC. stricta station, carnivores were replaced by suspension-feeders. Deposit-feeders dominated theCorallina cf.mediterranea stations affected by the warm-water effluent of a power plant. Other polluted stations, dominated byMytilus galloprovincialis andUlva cf.rigida, were dominated by grazers. The faunal destabilization was related to changes in the structural composition of the photophilic algal assemblage which were, in turn, related to the industrial contamination gradient along this coast.     

Occurrence of a cold-water coral along natural pH gradients (Patagonia, Chile)

Increasing dissolution of anthropogenic-released carbon dioxide into the world’s oceans is causing ocean acidification (OA). OA is thought to negatively affect most marine-calcifying organisms, notably cold-water corals (CWC), which may be especially sensitive due to the deep and cold waters they normally thrive in. However, the impact of OA on CWC is difficult to predict. Recorded distributions of CWC are rarely linked to in situ water chemistry, and the boundaries of their distributions are not clearly defined. The fjord Comau in Chilean Patagonia features pronounced pH gradients, and up to 0.5 pH units have been recorded both vertically (at some sites within 50 m depth) and less distinct horizontally (from head to mouth). The cosmopolite coral Desmophyllum dianthus grows along the course of the fjord and of the entire pH range. It occurs in shallow depths (below 12 m, pH 8.1) as part of a deep-water emergence community, but also in 225 m depth at a pH of 7.4. Based on pH and total alkalinity, data calculations of the associated carbonate chemistry revealed that this CWC thrives commonly close the aragonite (the orthogonal crystal form of calcium carbonate, the mineral structure of coral skeletons) saturation horizon and even below. This suggests a high adaptation potential of D. dianthus to adjust its calcification performance to conditions thermodynamically unfavourable for the precipitation of aragonite.     

Plankton biodiversity along a gradient of productivity and its mediation by macrophytes

We studied the effect of aquatic vegetation on the process of species sorting and community assembly of three functional groups of plankton organisms (phytoplankton, seston-feeding zooplankton, and substrate-dwelling zooplankton) along a primary productivity gradient. We performed an outdoor cattle tank experiment (n = 60) making an orthogonal combination of a primary productivity gradient (four nutrient addition levels: 0, 10, 100, and 1000 microg P/L; N/P ratio: 16) with a vegetation gradient (no macrophytes, artificial macrophytes, and real Elodea nuttallii). We used artificial plants to evaluate the mere effects of plant physical structure independently from other plant effects, such as competition for nutrients or allelopathy. The tanks were inoculated with species-rich mixtures of phytoplankton and zooplankton. Both productivity and macrophytes affected community structure and diversity of the three functional groups. Taxon richness declined with increasing plankton productivity in each functional group according to a nested subset pattern. We found no evidence for unimodal diversity-productivity relationships. The proportional abundance of Daphnia and of colonial Scenedesmus increased strongly with productivity. GLM analyses suggest that the decline in richness of seston feeders was due to competitive exclusion by Daphnia at high productivity. The decline in richness of phytoplankton was probably caused by high Daphnia grazing. However, partial analyses indicate that these explanations do not entirely explain the patterns. Possibly, environmental deterioration associated with high productivity (e.g., high pH) was also responsible for the observed richness decline. Macrophytes had positive effects on the taxon richness of all three functional plankton groups and interacted with the initial productivity gradient in determining their communities. Macrophytes affected the composition and diversity of the three functional groups both by their physical structure and through other mechanisms. Part of the macrophyte effect may be indirect via a reduction of phytoplankton production. Our results also indirectly suggest that the often reported unimodal relationship between primary productivity and diversity in nature may be partially mediated by the tendency of submerged macrophytes to be most abundant at intermediate productivity levels.     

Fluoride distribution in the environment along the gradient of a phosphate-fertilizer production emission (southern Brazil)

Airborne fluoride was determined in the rainwater, surface soil and groundwater along a gradient of emission of a phosphate fertilizer factory in Rio Grande, southern Brazil. Concentrations of fluoride in rainwater and groundwater achieved 3 mg l⁻¹ and 5 mg l⁻¹, respectively, and were dependent on pH. The fluoride deposited from emissions accumulated in a superficial horizon of soil in quantities comparable to those in the manufactured end-products—up to 23,000 mg kg⁻¹. Fluoride distribution in the environment is controlled by physical–chemical parameters of emission, rain intensity and soil properties. The highest fluoride concentrations were registered at a close distance of up to 2 km from the factory. The distribution of fluoride in groundwater resembled the same distribution in rainwater due to the high permeability of the local soils. Fluoride penetration to the groundwater also depended on the type of vegetation cover. The groundwater in woodland areas was less affected by contamination of fluoride than in the grassland areas, most probably because of the influence of eucalyptus throughfall, which increases the pH of wet precipitates.