Swamp Edge Research Articles

Batı Anadolu’da Silisleşmiş Ağaç Türlerinin Bazı Mineralojik ve Gemolojik Özellikleri

The silicified wood samples identified in Western Anatolia are located in the Late Miocene-Pliocene aged Çokköy Formation in Tavşanlı (Kütahya) and its surroundings, in Osmancalı (Manisa) and its vicinity in the Early (?)-Middle Miocene aged Foça Tuff and in Banaz (Uşak) around in the Middle-Late Miocene aged Yeniköy Formation within the terrestrial sediments. The formation of woods petrified by the silicification mechanism is associated with the sedimentation of clastic sediments formed simultaneously with the Neogene period volcanic activities in the region. In the mineralogical-petrographic examinations on three oriented thin sections, including transverse, radial and tangential, chalcedony polymorphs of silica and less quartz and opal were detected in silicified wood samples. Mineralogical interpretations were also supported by X-Ray Diffractometry (XRD) analysis. As a result of paleobotanical definitions made with thin sections in the botanical microscope; Taxodioxylon Hartig 1848 (Swamp cypress), Pinuxylon Gothan 1906 (Pine), Pterocaroxylon Müll.-Stoll et Mädel 1960 (Walnut), Quercoxylon (Kräusel 1939) Gros 1988 (evergreen oak), Glyptostroboxylon Conwentz 1884 (Swamp cypress) fossil wood species were identified. According to these findings, a warmer and more humid climate prevails than today, cypress forests on the edges of swamps and streams, and pine and evergreen oak forests on the slopes were determined. Within the scope of gemological examinations of silicified wood samples, samples which are rich in color/pattern were selected, polished by giving cabochon forms, then mounted with silver. A small amount of facet cutting studies were carried out from unpatterned and monochromatic samples. Silicified wood samples, which have high values in terms of hardness, exhibit an unstable character due to the weak zones they contain and do not show the desired performance in terms of pattern/color.

Diversity, dominancy and density of Tree Stage Plants of Sriwijaya University Forest Area Indralaya

There have been various environmental changes that have occurred within the Unsri campus area. After more than 30 years due to various factors such as the existence of human intervention activities has made swamp area narrow and will have an impact on changing diversity especially swamp edge tree vegetation in the Unsri campus area, it is necessary to conducted research that aimed to know diversity, dominancy and density of tree stage plants at Sriwijaya University campus area forest, Eight plots (10x10 m2) had been made and allthe trees with more than 10 cm diameter were counted. Simpson formula of dominancy and diversity were used and found index of dominancy 0.65 and diversity index is 0.35. Furthermore, density of trees is 31/800 m squares. Low index of diversity is caused by poor of species (two species Acacia mangium dan Melaleuca cajuputi).

The Rare Southern Twayblade (Neottia bifolia): Sentinel of Ecosystem Integrity For Sphagnous Swamps

Long-term monitoring of the rare southern twayblade (Neottia bifolia; Orchidaceae) and understorey of a black spruce-tamarack, swamp community was conducted after construction of an airport taxiway above the swamp edge. Succession documented over 14 years in the treed swamp edge following disturbance involved loss of the twayblade, invasion by guilds of annuals, and shifts between original and new guilds of wetland plants. Despite changes, the twayblade was the only plant extirpated from the swamp edge community although fungal richness (mainly basidiomycete) was substantially lower in the edge than the swamp interior. NMS ordination indicated that the orchid niche is an undisturbed swamp with an intact tree canopy and unbroken mat of Sphagnum which supports a diverse mycorrhizal community adapted to summer water table drawdown and low ionic groundwater chemistry (e.g. Cl<10 mg/L). Fourteen years after the disturbance, southern twayblade populations in the swamp interior, 100 m from the edge were in steady decline. The woodland orchids may be sentinels of ecosystem integrity. Loss of the twayblade signalled the onset of a post-development, disturbance-cascade: installation of an impervious surface restricted infiltration, altered run-off quantity and quality which subsequently resulted in loss of the ecosystem engineer, Sphagnum, and keystone mycorrhizal fungi.

Distribution, Habitat Preference, and Status of the Ditch Fencing Crayfish, Faxonella clypeata (Hay) (Decapoda: Cambaridae), in Arkansas

The ditch fencing crayfish, Faxonella clypeata (Hay), is a common and widespread crayfish that inhabits roadside ditches, intermittent first-order streams, shallow sloughs with heavy vegetation, and edges of swamps in Arkansas. Between 1997-2012, we made 55 collections of F. clypeata in 34 counties throughout eastern Arkansas, including 23 counties where F. clypeata had not been previously documented. At most of these locations within the West Gulf Coastal and Mississippi Alluvial Plain provinces, F. clypeata was found to be a locally abundant crayfish. With regard to conservation status, F. clypeata should be considered as “Currently Stable” due to its widespread distribution and general abundance throughout its range in the state.

RELATIONSHIP BETWEEN HABITAT AND LANDSCAPE FEATURES AND THE AVIAN COMMUNITY OF RED MAPLE SWAMPS IN SOUTHERN RHODE ISLAND

We investigated the relationship between habitat and landscape characteristics and the abundance and species richness of breeding birds in 12 southern Rhode Island red maple (Acer rubrum) swamps of varying size (0.5–19.2 ha). Swamp size was the most important landscape variable explaining variation in species richness for the entire bird community and for individual habitat use groups (forest interior, interior-edge, and edge species). Richness increased log linearly with size. Increased richness appeared to be due to increased habitat heterogeneity within the swamp and at the swamp edge, not a core area effect. Bird relative abundance was not predictable from swamp size. The abundance of forest interior birds was positively related to the amount of upland forest within 1–2 km of a swamp and negatively related to the regional abundance of swamp forest; the relationships between these landscape variables and the species richness of edge-related species were just the reverse. The amount of shrub foliage 2–4 m above the ground also was a positive predictor of the abundance of forest interior birds. Variation in overall bird abundance was explained by models based on peat depth and the availability of swamp forest within 1–2 km. All four of the most common forest interior species—the Veery (Catharus fuscescens), Northern Waterthrush (Seiurus noveboracensis), Black-and-white Warbler (Mniotilta varia), and Canada Warbler (Wilsonia canadensis)—occurred in swamps as small as 1 ha. This pattern suggests that overall landscape composition (i.e., total forest availability) may be more important than swamp patch size in explaining the occurrence of these area sensitive species.

Edge Effects and Conservation of Biotic Diversity

For three-quarters of a century edge or zone of transition between different ecological associations has intrigued ecologists. high diversity of plants and animals associated with edges and ecotones quickly became known as edge effect principle, which is widely referred to as a fundamental concept of ecology (e.g., Wiens 1976). For 55 years since enunciation as a game management principle, wildlife biologists have considered that the potential density of game of low radius requiring two or more types is, within ordinary limits, proportional to sum of type peripheries (Leopold 1933:132). Standard habitat management guides include prescription to create as much 'edge' as possible because wildlife is a product of places where two habitats meet (Yoakum & Dasmann 1971). But increasing emphasis on plant and nongame wildlife conservation during last two decades has revealed many characteristics of edges and ecotones that are now considered undesirable. term derives from Greek root tonus, referring to tension. As originally coined, referred to zone of tension between ecological communities. As it turns out, term was a harbinger of tension that now exists between scientific communities. Debate about whether land managers should or should not continue to prescribe creation of edges in name of wildlife conservation now simmers in wildlife profession and several land management agencies. This subject was topic of a special session at 1987 annual meeting of Society for Conservation Biology. This introduction and three of five papers presented in that session provided historical and much of contemporary basis for evaluating such land management decisions. As originally formulated, The line that connects points of accumulated or abrupt change ... is a stress line or ecotone (Clements 1907:297). This as well as other early formulations clearly alluded to a onedimensional concept, and ornithologists such as Kendeigh (1944) and Johnston (1947) went so far as to conclude that bird densities should be reported as pairs per 100 acres for forest interior species, but pairs per mile of edge for edge species. Numerous indices aimed at assessing habitat interspersion and/or landscape diversity-for example, shoreline index-are based on this one-dimensional aspect of edge (Welch 1948; Baxter & Wolfe 1972; Scheurholtz 1974; Patten 1974; Fried 1975; Ghiselin 1977; Taylor 1977; Thomas, Maser, & Rodiek 1979; Asherin, Short, & Roelle 1979; Hays, Summers, & Seite 1981). But confusion surrounding nature of edges and ecotones emerged shortly after concept was coined. Shelford (1913) clearly referred to a two-dimensional phenomenon when he stated The forest margin, as we have seen, possesses in addition to characteristic species . .. . and Deventer (1936) treated swamp edge, forest edge, and fence row as though they were discrete habitat types. Johnston (1947) concluded her classic study by stating The forest edge is considered to be a distinct community because it is inhabited by a characteristic set of species.... Beecher's (1942) analysis nearly foretold current forest management quandary when he observed that forest margins only function as edge habitat when their extent is greater than some minimum threshold acreage. Richard Yahner has published extensively on topic of edge effects as they pertain to various groups of wildlife and his paper presented here reviews these various issues as they are understood by practicing wildlife ecologists and managers. Swynnerton was perhaps first to be confronted with intrinsic contradictions of managing for edge ef-

Swamps, canals, and the locations of ancient Maya cities

The recent radar mapping discovery of widely distributed patterns of intensive agriculture in the southern Maya lowlands provides new perspectives on classic Maya civilization. Swamps seem to have been drained, modified, and intensively cultivated in a large number of zones. The largest sites of Maya civilization are located on the edges of swamps. By combining radar data with topographic information, it is possible to suggest the reasons for the choice of urban locations. With the addition of patterns elicited from rank-ordering of Maya cities, it is also possible to suggest more accurate means of defining Classic period Maya polities.

Ramalina paludosa, a New Species from Florida

The new species Ramalina paludosa is a small caespitose plant occurring sporadically throughout Florida on Taxodium distichum in swamps. It is morphologically and chemically distinct from the other species of Ramalina in Florida. Although there are nine species of Ramalina in Florida, the genus is generally uncommon except near the coast. However, I found a small and apparently undescribed Ramalina to be quite common in inland swamps. The new species, R. paludosa, has probably been overlooked because of its small size and its habitat in swamps, and because of a generally poor representation of Florida lichens in herbaria. Ramalina paludosa is usually smaller than R. complanata (Sw.) Ach. and R. denticulata (Eschw.) Nyl., the other compressed, tuberculate species of Ramalina in Florida. In addition, the medullary reaction of the new species is C+ red rather than Cas in R. complanata and R. denticulata. For discussion of the chemistry of R. paludosa, see Culberson (1967). Single specimens sometimes occur on fence posts and hardwood trees, but R. paludosa is abundant only on Taxodium distichum (bald cypress). It is generally most common on the upper branches of Taxodium except at the edges of swamps where it is on the twigs, the lower branches, and even the trunks. Ramalina paludosa is sporadically distributed but locally abundant in swamps throughout the state (Fig. 1). However, while it is quite abundant in some swamps, it may be entirely lacking from similar sites nearby. 1 Research carried out under National Science Foundation Grant GB-1239 to Duke University. 2 Department of Botany, Duke University, Durham, North Carolina 27706. This content downloaded from 157.55.39.177 on Wed, 16 Nov 2016 04:33:57 UTC All use subject to http://about.jstor.org/terms 316 THE BRYOLOGIST [Volume 70 FIGURE 1. The known distribution of Ramalina paludosa. Ramalina paludosa B. Moore, sp. nov. (Fig. 2). Thallus parvus, caespitosus, ramosissimus, ramulis compressis sed ad apicem teretibus. Apothecia terminalia vel subterminalia, 1-5 mm lata; sporae ellipsoideae, 1-septatae, 3-5 X 9-12/,. Cortex K-; medulla, K-, C+ rubescens, KC+ rubescens, PD-. Acidum usnicum in cortice et acidum cryptochlorophaeicum in medulla. Thallus greenish, caespitose, small, usually less than 3 cm long, much branched, usually dichotomously; branches 0.5-1 mm broad, compressed in part but terete at the tips, tuberculate. Apothecia common, terminal or subterminal, 1-5 mm broad, the disk tan, convex or flat; spores ellipsoid, 1-septate, 3-5 X 9-12 /u. Cortex K-; medulla K-, C+ red, KC+ red, PD-. Usnic acid in the cortex and cryptochlorophaeic acid in the medulla. Type: FLORIDA. GILCHRIST CO.: Trenton, Moore 3897 (DUKE-holotype).

A Winter Bird Community in Western New York

Although the tendency of birds of different species to associate in looselyknit flocks in winter has been frequently noted, there has been no systematic analysis of such flocks and their component species from the standpoint of habitat preference and reaction to particular environmental factors. The present study involves an analysis of the activity of a four-species habitat group, consisting of the northern downy woodpecker, Dryobates pubescens ntedianus (Swainson), the northern white-breasted nuthatch, Sitta carolinensis carolinensis Latham, the black-capped chickadee, Penthestes atricapillus atricapilfis (Linnaeus), and the eastern tree sparrow, Spi'ella arborea arborea (Wilson). This group was studied with reference to selection of community type, horizontal level of activity, response to temperature and general weather conditions, number of birds per unit of area, and percentage of association among members of the group. The study was carried on during December, 1934, and January and February, 1935, in connection with a survey of the wild life of a game and nature preserve in Monroe County, New York, undertaken for the Monroe County Park Commission. The preserve, known as Mendon Ponds Park, comprises approximately 1700 acres. The land consists mostly of gravel hills, among which are numerous dry kettle holes, and several swamps and small lakes. Approximately half of the land was farmed before 1928, when the preserve was created. Very little reforestation has been done, and the abandoned fields are now weedy meadows with occasional scattered shrubs. Along the old field borders there are a few trees and a great deal of shrubby growth. Nine old dwelling sites with abandoned orchards are included in the area. There are approximately 400 acres of forest in the preserve, including about 40 acres of swampy woodland. The beech, which occurred in the upland forest before the land was settled, has mostly been cut, and only young beech is now found. Otherwise the upland forest has been relatively unmolested. The following community types occur in the preserve: (1) Open Lake, (2) Swamp, (3) Swamp Edge, (4) Swampy Woods, (5) Upland Woods, (6) Forest Edge, (7) Isolated Thicket, (8) Open Weedy Meadow, (9) Brushy Fence Row, (10) Abandoned Orchard, (11) Dwelling Environs. The dominant and chief subdominant plants for each type are shown in the accompanying table (table I). 491