The composition and structure of a dry, semideciduous forest in western Ecuador

In the coastal range of western Ecuador, we established a one-hectare plot in dry, semideciduous forest at 320–365 m elevation (l°26'S 80°41'W). Within the plot, we recorded all trees ≥ 5 cm dbh. There were present 538 trees and 655 stems with a total basal area of 7.5 m². Taxonomically the trees represented 37 species and 22 families. Ampelocera sp. was the most important species with 37% of the IVI. Acnistus arborescens, Solarium confertiseriatum , and Zanthoxylum o f. fagara , are dominant pioneer species in the plot. The structure and flora of the forest are strongly influenced by severe disturbance caused by selective logging 12 years ago. An index of dispersion based on frequencies was used to infer spatial patterns of the 15 most abundant tree species (n = 4–188). Seven species showed clumped distributions, and the degree of clumping was not correlated with abundance. Conservation of this forest type is worthwhile because its recovery is fast and it can act as a refuge for plant and animal species.     

Tree population dynamics in Kibale National Park, Uganda 1975–1998

Changes in species composition, stem abundance, and basal area of trees taller than or equal to 10 m in a medium altitude tropical rain forest at the Ngogo study area, Kibale National Park, Uganda are described for the period between 1975 and 1998 ( n  = 23 years). Two enumeration episodes were conducted in 263 plots of 5 m by 50 m during 1975–80 and 1997–98. During this period, species richness decreased by 3% (from 92 to 89). Species diversity (H') also declined slightly from 2.97 to 2.86. The number of trees recorded in the sample plots decreased by 8% (from 2545 to 2329), while basal area decreased from 49.48 m² ha⁻¹ to 48.68 m² ha^−1. However, stem abundance and basal area increased for some species.     

Composition and structure of a species rich Amazonian rain forest obtained by two different sample methods

Inventory data for trees ≥ 10 cm DBH from a hectare plot are compared to data obtained by the Point-Centered Quarter Method along a line transect from the same locality in Anangu, Amazonian Ecuador. The one-hectare quadrat plot of 100 × 100 m had 734 individuals, 153 species, 46 families, a total basal area of 22.2 m², and an estimated above ground tree volume of 240.5 m³. The line transect had a calculated density of 728 individuals per hectare, which included 239 species, 51 families, a total basal area of 34.1 m², and an estimated above ground tree volume of 409.6 m³. Of the 20 species with the highest IVI, only four were shared by the two samples. The most important species were Quararibea ochrocalyx on the hectare plot and Iriartea deltoidea on the line transect, constituting 26.6 and 13.3% of the individuals, respectively. The five families with the highest FIV on the hectare plot (Bombacaceae, Arecaceae, Moraceae, Caesalpinaceae, and Lauraceae) and on the line transect (Arecaceae, Moraceae, Meliaceae, Mimosaceae and Caesalpinaceae) constitute 40.4% and 35.4% of the Family Importance Values of the samples, respectively. The Point-Centered Quarter Method used along a line transect reflects maximum diversity and provides average values of density and tree size in the area. The quadrat plot reflects the local structure and composition of the forest within the plot.     

Elevational parallels of latitudinal variation in the proportion of lianas in woody floras

Aim  To determine if elevational variation in the proportion of lianas in woody floras parallels the variation observed on latitudinal gradients. This is to be expected if the poleward decrease in the importance of lianas is related to the vulnerability of their wide vessels to freeze embolism.
Location  Coastal ranges of south-central Chile (latitude 37°–40° S) and western South Island of New Zealand (41°–43° S).
Methods  The presence of all woody species was recorded in plots of 2500 m² (Chile) or 100–400 m² (New Zealand) on four elevational gradients in temperate rain forest. Each species was classified as a tree, shrub or liana. Original data were obtained from 22 plots at two sites in Chile. In New Zealand, two surveys comprising a total of 296 plots were extracted from the National Vegetation Survey data base.
Results  Liana species richness declined more or less monotonically on all four gradients, whereas richness of trees and shrubs showed more varied elevational patterns. The proportion of woody species contributed by the liana life-form was negatively correlated with elevation on all four gradients, falling from 15 to 35% of the woody flora at c . 200 m a.s.l. to nil well below the tree line. The elevational and latitudinal limits of liana species were marginally significantly correlated in Chile, but not in New Zealand.
Main conclusions  The elevational parallel of the well-documented decline in liana representation with increasing latitude is consistent with the hypothesis that cold intolerance is a strong control on the global distribution of the liana life-form.     

Composition and structure of a humid montane forest on the Pasochoa volcano, Ecuador

In a one-hectare plot in humid montane forest on Volcán Pasochoa (3,260–3,300 m), one of the last remnants of the inter-Andean forest between the two Ecuadorean cordilleras, there were 1,058 trees ≥ 5 cm dbh in 32 different species with a total basal area of 25.7 m². The most common species were Miconia theaezans, Piper andreanum , and Miconia pustulata with 32%, 14% and 8% of the individuals, respectively. Three species ( Hesperomeles lanuginosa, Boehmeria fallax and Lamiaceae sp.) were represented by only a single individual. Melastomataceae was the most important family with six species, over 50% of the individual trees, and 68% of the basal area. Other important families were Piperaceae and Asteraceae. The abundance of assumed pioneer species suggests that either the forest has been altered by humans in the past, or that their dominance is a part of the dynamic regeneration of a forest growing on steep slopes with inclinations between 36 and 120% in the plot. The diameter class distribution of Miconia corymbiformis and Axinaea macrophylla shows a light-demanding species behavior. Trees with multiple stems characterize this forest perhaps in order to distribute their weight on such steep slopes.     

The forest of Vorsø, Denmark: Succession towards a natural, decidous boreal forest influenced by breeding cormorants

The forest on the strictly protected island Vorsø in Horsens Fjord has since 1952 been examined every ten years to discover the number, basal area, wood volume and aboveground biomass of the species. This paper describes the results from 1982 and the development up to that. The dominating species are Fraxinus excelsior, Ulmus glabra and Fagus sylvatica. The two forests, "Vesterskov" (6.09 ha) and "Østerskov" (2.48 ha) respectively, were, in 1982, still immature. Their number of stems per ha were: 756 and 509; basal area: 38 m² and 45 m². volume: 544 m³ and 615 m³; biomass 207 t and 268 t. The annual increase 1972–1982 was respectively 8.8 m³/ha and 0.3 m³/ha. The impact of the cormorant ( Phalacrocorax carbo sinensis ) is especially in "Østerskov" increasing, since the colony here was established in 1976. The succession of the forest is discussed in relation to the disturbance by the cormorants.     

Structure, floristic composition, and vegetation forming factors of three vegetation types in Senegal

Six 1 ha plots were established in a coastal savanna, called Fathala Forest, in Delta du Saloum National Park, Senegal. Two plots were placed in woodland, two in wooded grassland, and two in transition woodland in order to describe structure and floristic composition of the vegetation. All trees ≥ 5 cm dbh were sampled. The three selected vegetation types showed distinct differences in structure as well as in species composition. Woodland had high density (440–449 individuals per ha), many small trees, and high basal area (13.4 m²per ha). Transition woodland was characterised by low density (54–118 individuals per ha) but many large trees and a relatively large basal area (8.6–12.8 m² per ha). Wooded grassland was characterised by medium sized trees, it had low density (86–102 individuals per ha) and low basal area (3.8–5.7 m² per ha). Species richness ranged between 17 and 27 species per ha in the six plots. Only two species were found in all plots, Daniellia oliveri (Caesalpiniaceae) and Prosopis africana (Mimosaceae). Legumes dominated all plots. Wooded grassland and transition woodland had many characteristics of fire-affected vegetation in contrast to woodland. Today wooded grassland encroaches on woodland and transition woodland. Management of the latter two vegetation types should be given priority as they maintain structural and floristic characteristics that are essential to conserve biodiversity and original features of the vegetation, and they are also important for local people who are allowed to make sustainable use of the vegetation.     

Small-scale patterns of species richness in Swedish semi-natural grasslands: the effects of community species pools

Temperate semi-natural grasslands are known for their high plant species richness at small spatial scales. We examined the variation in small-scale species richness in a sample of 63 sites from Swedish semi-natural grasslands, located as fragments in the modem landscape dominated by forest and agricultural land. Data were obtained from two spatial scales at each site. 1 dm² and 4 m². Using an analysis based on a Monte Carlo simulation, we found support for the species-pool hypothesis: a high species richness at the I dm- scale was associated with high species richness at the 4 m2 scale. The conclusion from this pattern analysis would, however, be considerably strengthened if we could reduce the likelihood that other mechanisms than sampling from species pools of unequal size influence the pattern of small-scale species richness. Additional analyses were made in order to identify such mechanisms. We examined whether four putative key traits: seed size, seed production, plant size and reproductive allocation were different among species at comparatively species-rich vs species-poor I dm' plots. We found only a little evidence for such differences. There was a weak tendency that species in the plots with high species richness possessed larger (and fewer) seeds than species from species-poor plots. Our results are congruent with the main prediction of the species pool model: variation in small-scale species richness (1 dm²- scale) is basically a result of sampling from unequally sized community species pools (4 m² scale). Variation in species richness between the 4 nr semi-natural grassland "patches" may thus be sought for among mechanisms operating al larger spatial scales than 4 m². We briefly discuss such mechanisms, based on other studies performed in the same study area.     

Soil Charcoal in Old-Growth Rain Forests from Sea Level to the Continental Divide

Soil charcoal is an indicator of Holocene fires as well as a palaeoecological signature of pre-Colombian land use in Neotropical rain forests. To document rain forest fire history, we examined soil charcoal patterns in continuous old-growth forests along an elevational transect from sea level to the continental divide on the Atlantic slope of Costa Rica. At 10 elevations we sampled 1-ha plots, using 16 cores/ha to collect 1.5-m deep soil samples. We found charcoal in soils at every elevation, with total dry mass ranging from 3.18 g/m² at 2000-m elevation to as much as 102.7 g/m² at 300 m. Soil charcoal is most abundant at the wettest lowland sites (60–500 m) and less at montane elevations (> 1000 m) where there is less rainfall. Between 30- and 90-cm soil depth, soil charcoal is present consistently and every 1-ha plot has charcoal evidence for multiple fire events. Radiocarbon dates range from 23,240 YBP at 1750-m elevation to 140 YBP at 2600 m. Interestingly, none of the charcoal samples from 2600 m are older than 170 yr, which suggests that forests near the continental divide are relatively young replacement stands that have re-established since the most recent localized volcanic eruption on Volcán Barva. We propose that these old-growth forests have been disturbed infrequently but multiple times as a consequence of anthropogenic and natural fires.     

Colony structure, seasonality and food requirements of the crazy ant, Anoplolepis longipes (Jerd.), in the Seychelles

Abstract. 1. In Seychelles, A. longipes nests on the ground and in trees, underground nests do not occur, possibly because soils are too hard or unstable.
2. Nest density approached 700 ha^-1 in some areas and nests contained, on average, about 4000 ants. The total population (including foragers) in heavily infested areas may exceed 10 millions ha^-1.
3. On average, each nest contained about forty queens and fifty males, although only 50% of nests contained males. A few nests contained up to 300 queens, 1000 males, 36 000 workers and 23 000 brood.
4. Production of sexual adults and brood was related to the wet season, most being produced shortly before or after the heavy rains from November to March.
5. Natural spread is probably by budding of colonies which, during an expansive period, may advance 1 m day^-1.
6. Food collected by the colony included sugary substances from fruits, honey-dew-producing insects and plant exudates, and proteinaceous material, mainly in the form of insect prey and carcases. A forager collected, on average, 1.2 mg of liquid or 2.8 mg of solid material on each foraging trip.
7. Foraging occurred at fluctuating intensities throughout the day and night, but was limited by heavy rain, strong winds and substrate temperatures above 30°C. Maximum activity occurred at ground temperatures of 25–30°C and ceased about 44°C.
8. Availability of food and nest sites proably have the greatest influence on population size.     

Species composition and vegetation structure of an upper montane forest at the summit of Mt. Doi Inthanon, Thailand

Upper montane forest (UMF) within Doi Inthanon National Park, Northern Thailand, was investigated by means of fifty, 40 × 40 m stratified random plots situated between 2080 and 2565 m altitude. The aim was to address a number of community ecological questions concerning woody species composition and structural heterogeneity of the forest. A total of 7474 individuals of trees and woody climbers ≥ 15 cm gbh (girth at breast height) were included in the study and these were identified to 47 species, 39 genera and 26 families. The average density was 934 individuals/ha and the average stem basal area was 71.8 m²/ha. The most important species were: Quercus eumorpha, Sjzygium angkae, Litsea martabanica, Helicia nilagirica, Lindera caudata, Schima wallichii, Osmanthus fiagrans, Eurya acuminata, Myrsine semiserrata and Ilex umbellulata and the most important families were Fagaceae, Lauraceae, Theaceae and Myrtaceae. Altitude was the most important environmental variable explaining species composition and vegetation structure. Most of the calculated vegetation variables showed significant correlation with altitude: species richness, family richness, diversity, density and crown cover declined with altitude, average tree height was uncorrelated with altitude and basal area increased with altitude. An analysis of size class distributions indicated good forest conditions and reverse-J-shaped age class distribution of most species.     

Persistence of vascular plants in a Norwegian boreal coniferous forest

Persistence, the tendency of a species to remain in its original position and not to colonize new sites, is studied for the most abundant forest vascular plants (25 species in spruce forest and 7 in pine forest) in Solhomfjell, Gjerstad, S Norway Data sets included presence/absence in 199 meso plots (1 m²) and 3184 subplots (1/16 m²), analyzed over a 5 yr interval, and a subset of 50 meso plots and 800 subplots, analyzed for six consecutive years Relationships between species variables (seedling frequency and mobility rate compiled from the literature, and cover and abundance means in the study area) are studied, and related to species optima along ecologically interpreted DCA ordination axes Vascular plant mobility may increase towards nutrient-poor sites Dominance in the boreal forest floor is mostly by clonal species Persistence was calculated for different temporal (1-5 yr) and spatial (1/16 and I m²) scales Persistence patterns in the spruce and pine forests were similar, but persistence decreased towards the xeric pine forests One main component of variation in persistence was demonstrated by PCA analyses the absolute level of persistence, which is related to seedling recruitment vs clonal growth, and within clonal species to ramet longevity, abundance, mobility, growth pattern and mode of surviving the infavourable season Minor components of variation in persistence were related to spatial scale and temporal scale Persistence characteristics were species-specific and varied little between years Numerous species characteristics were relevant to interpretation of variation in persistence, indicating a continuous, multidimensional variation in life history characteristics     

Species richness and endemism of plant and bird communities along two gradients of elevation, humidity and land use in the Bolivian Andes

Abstract.  We studied the patterns of species richness and range–size rarity (as a measure of endemism) of two plant groups (Pteridophyta, Bromeliaceae) and birds along two gradients of elevation, humidity and human land use in a forested Andean valley. Both transects covered the transition from an arid valley bottom through a cloud forest zone to relictual high-elevation Polylepis forest, but transects differed in overall precipitation. Plants were surveyed in 88 plots of 400 m² each, while birds were detected primarily through visual observations and tape recordings over areas of 0.3–1.5 km². Global range sizes of all species were mapped on 1°-grids and range-size rarity was calculated as the mean inverse range size of all species recorded in elevational steps of 200 m. Patterns of species richness and range–size rarity were mainly unrelated between and within study groups. Monotonic increases and decreases and hump-shaped patterns were observed for species richness as well as range–size rarity. Several of these patterns can be interpreted in the light of the ecological requirements of each taxonomic group, e.g. dependence of fern species richness on humidity or of bird richness on habitat complexity. Species richness of ferns and birds peaked at higher elevations along the less rainy transect, possibly as a result of higher levels of solar radiation and ecosystem productivity. Patterns of species richness and endemism of the study groups are causally unrelated and cannot be used to predict those of other groups at the spatial scale of this study. Human impact was highest in areas of mostly low to intermediate species richness, but was often high in zones of high endemism.     

Effects of experimental small-scale grassland fragmentation on spatial distribution, density, and persistence of ant nests

Abstract.  1. Grassland fragmentation is expected to influence the abundance of different invertebrate species to a different extent. Fragmentation-related effects are of particular importance in species that interact with many other species.
2. The density and spatial distribution of nests of 15 ant species in experimentally fragmented calcareous grasslands at three sites in the Northern Swiss Jura mountains were examined. Fragments of different size (0.25 m², 2.25 m², and 20.25 m²) were isolated by a 5-m wide strip of frequently mown vegetation. Control plots of corresponding size were situated in adjacent undisturbed grassland.
3. Three years after initiation of the experiment, ant nest density did not differ between fragments and control plots. Six years after initiation of the experiment, however, ant nest density and forager abundance were higher in large fragments than in large control plots. Ant nests tended to occur more frequently along the edge of fragments than in the core area. Persistence time of nests of the most abundant species, Lasius paralienus , tended to be shorter in fragments than in control plots. Furthermore, persistence time was longer in nests situated close to the fragment edge than in nests in the core area.
4. Effects on nest density, edge effects on the spatial distribution of nests, and the relationships between nest density and environmental factors were more pronounced when only nests of L. paralienus were considered. The implications of these findings for plant and other invertebrate species are discussed.     

Fruit and seed ecology of wild robusta coffee (Coffea canephora Froehner) in Kibale National Park, Uganda

Coffee fruit production, frugivorous activities and seed longevity were investigated during two seasons. The average densities of fruiting coffee trees during the first sampling period ranged from four to seven per 25 m² and during the second sampling period, four fruiting trees per 25 m² were estimated. Fruiting coffee trees were significantly less than the non-fruiting trees ( P < 0.05, t -test). Periods of maximum coffee fruit fall coincided with those of lowest rainfall. Coffee fruit yield per tree from ground collections was 7–40 m⁻² in 1992 and 16–38 m⁻² in 1993/1994. Split coffee berries ranged between 71.7% and 83.6% of all fruits collected from the forest floor in the 1993/94 sampling period. Coffee seeds collected from the forest floor were mostly undamaged. Black and white colobus and redtail monkeys were observed to feed on ripe coffee fruits but did not crush the seeds. Coffee seed viability declined rapidly during storage. Seeds left on the forest floor survived longest, those stored under laboratory conditions lost viability fastest, and those in cold storage showed intermediate longevity.     

Short-term thermal acclimation induces adaptive changes in the inner mitochondrial membranes of fish skeletal muscle

In the oxidative muscles (musculi laterales superficiales) of crucian carp Carassius carassius acclimated for 6 weeks to either 5 or 25° C, the volume density and the surface density of fibres per tissue did not differ significantly between the control and experimental groups. The correlation ratio (μ²) for these values was below 50, 39·3 and 43·9 respectively. After acclimation to 5° C, the surface density of outer mitochondrial membrane per fibre increased significantly from 0·93 to 1·23m² cm⁻³ in the summer population but dropped from 0·94 to 0·67 m² cm⁻³ in the winter population. The surface density of outer mitochondrial membrane per mitochondrion increased from 3·24 to 4·52 m² cm⁻³ in summer fish. After acclimation to 25° C, the surface density of inner mitochondrial membranes per muscle fibre decreased from 4·04 to 1·79 m² cm⁻³ in summer fish and from 3·86 to 1·07 m² cm⁻³ in winter fish. The surface density of inner mitochondrial membranes per mitochondrion increased from 14·17 to 15·60 m²cm⁻³ in summer fish but dropped from 13·91 to 10·67 m² cm⁻³ in winter fish. Correlation matrices demonstrate a negative correlation of the surface density of outer mitochondrial membrane per mitochondrion with the volume density of mitochondria per fibre and temperature, suggesting cold-induced proliferation of small mitochondria. It was concluded that short-term cold acclimation increased surface area of the inner mitochondrial membranes in summer fish.     

Plant biodiversity and conservation of tropical semi-evergreen forest in the Shervarayan hills of Eastern Ghats, India

Species diversity, density, population structure and dispersion patterns of all trees and lianas (30cm gbh) were inventoried in a tropical semi-evergreen forest in the Shervarayan hills of Eastern Ghats, south India. Such data are necessary for ecosystem conservation of the under-studied Eastern Ghats, as extensive forests here have already been converted to coffee and orange plantations and the landscape changed due to aluminium ore mining and quarrying. Four 1-ha plots were established in Sanyasimalai (SM) reserve forest of the Shervarayan hills, one plot (SM1) located close to mining and quarrying area, two other contiguous plots (SM2 and SM3) located in selective felling area and the fourth (SM4) in a relatively undisturbed forest. These are 1 to 4km apart in the same semi-evergreen forest tract. In the four study plots a total of 3260 stems (mean density 815ha–1) covering 80 species in 71 genera and 44 plant families were recorded. Species richness was greatest in the undisturbed plot SM4 (50), while lowest (33) in the selectively felled site SM2. The forest stand (SM4) was also denser (986 stemsha–1) and more voluminous (basal area 44.3m2ha–1 as compared with the site mean of 35m2ha–1) than the other plots. Four trees, Chionanthus paniculata, Syzygium cumini, Canthium dicoccum and Ligustrum perrottetii dominated the stand, collectively contributing to >50% of the total density. Species richness and stand density decreased with increasing tree girths. The forest stand contained a growing population, but there was considerable variation in basal area distribution between the plots. Trends in species population structure varied, particularly for selective-felled species. Most species exhibited clumped dispersion of individuals both at 0.25ha and 1-ha scales. Variation in plant diversity and abundance are related to site attributes and human impacts.     

红灵山亚热带常绿阔叶林维管植物组成与群落结构特征

为了弄清四川天全县红灵山亚热带常绿阔叶林的群落类型及结构特征,在红灵山中山地段（海拔1700~2000 m）设置6个20 m×30 m的代表性样地,采用典型群落调查法,对其物种组成、群落结构、生物量和自然更新能力等进行研究。结果显示：（1）样地内调查到182个物种,属72科117属,显示出典型亚热带常绿阔叶林的植物区系组成特征;（2）以扁刺栲群系为主,可分为3个群丛组、5个群丛;（3）乔木层密度为2583~5383株/hm²,生物量为2.42×10⁵~4.26×10⁵ kg/hm²,冠层藤本植物地上生物量为1.01×10³ kg/hm²,死木质残体生物量为1.65×10⁵ kg/hm²,次生性特征明显;（4）幼苗丰富,其种类组成与乔木层的相似度为88.89%,说明其自然更新良好,群落结构正渐趋稳定。综合分析表明,红灵山的常绿阔叶林以扁刺栲群系为主,虽次生性明显,但目前保存较为完好,值得进一步强化生态保育。     

Forest association and phenology of wild coffee in Kibale National Park, Uganda

A study on the forest association and phenology of wild coffee ( Coffea canephora Pierre) was conducted in Kibale forest, Uganda. Nested quadrats were used to enumerate tree species, including coffee and herbaceous plants associated with forest and coffee stands. A total of 150 coffee trees was marked along transects and monthly scans carried out to score for fruits, flowers, leaves and leaf insect damage. Pre- and post-dispersal predation levels and coffee yield estimates were made by examining fruits from trees, forest floor and seasonal fruit falls into demarcated plots. In the forest, wild coffee stands are associated with low-quality forest types in terms of timber species (about 10.5 canopy species/study site) and low stocking densities of trees ≥ 50 cm d.b.h. (average 38 trees ha⁻¹ for each site) and poor forest regeneration. In the forest, wild coffee reproductive phases overlap with ripening, coinciding with flower bud and flower production. The variable peak ripening season falls between November and April. The wild coffee yields are generally low (average of 3.5 intact fruits 16 m⁻² month⁻¹), with low insect fruit/seed damage (4–19%) but high levels of wastage due to monkeys, bats and birds.     

Sea-level rise and drought interactions accelerate forest decline on the Gulf Coast of Florida, USA

Sea-level rise threatens low-lying coastal ecosystems globally. In Florida, USA, salinity stress due to increased tidal flooding contributes to the dramatic and well documented decline of species-rich coastal forest areas along the Gulf of Mexico. Here, we present the results of a study of coastal forest stand dynamics in thirteen 400 m² plots representing an elevation gradient of 0.58–1.1 m affected by tidal flooding and rising sea levels. We extended previously published data from 1992–2000 to 2005 to quantify the full magnitude of the 1998–2002 La Niña-associated drought. Populations of the dominant tree species, Sabal palmetto (cabbage palm), declined more rapidly during 2000–2005 than predicted from linear regressions based on the 1992–2000 data. Dramatic increases in Juniperus virginiana (Southern red cedar) and S. palmetto mortality during 2000–2005 as compared with 1995–2000 are apparently due to the combined effects of a major drought and ongoing sea-level rise. Additionally, coastal forest stands continued to decline in species richness with increased tidal flooding frequency and decreasing elevation. Stable isotope (H, O) analyses demonstrate that J. virginiana accesses fresher water sources more than S. palmetto . Carbon isotopes reveal increasing δ ¹³C enrichment of S. palmetto and J. virginiana with increased tidal flooding and decreased elevation, demonstrating increasing water stress in both species. Coastal forests with frequent tidal flooding are unable to support species-rich forests or support regeneration of the most salt-tolerant tree species over time. Given that rates of sea-level rise are predicted to increase and periodic droughts are expected to intensify in the future due to global climate change, coastal forest communities are in jeopardy if their inland retreat is restricted.