South Coastal Plain Research Articles

Holocene vegetation evolution, hydrologic variability and sea-level fluctuations on the south coastal plain of Laizhou Bay, Bohai Sea, China: new evidence from pollen, freshwater algae and dinoflagellate cysts

Holocene vegetation evolution, hydrologic variability and sea-level fluctuations on the south coastal plain of Laizhou Bay, Bohai Sea, China: new evidence from pollen, freshwater algae and dinoflagellate cysts

Evaluation of Wind Power for Electrical Energy Generation in the Mediterranean Coast of Palestine for 14 Years

The generation, distributionand transmission of electricity in Palestine have recently emerged as major issues. This study comprehensively assesses the production of wind energy and the estimation of wind energy potential in Palestine’s south coastal plain. The goal is to evaluate Palestine’s wind energy production by studying wind data and calculating energy and power. This study analyses two actual time series datasets. Findings are elaborated to determine the wind energy conversion per 1 m2. The wind speed data from January 1996 to December 2006 in Gaza and from January 2012 to December 2015 in Ashqelon are selected as the data sample. This study is crucial given the need for clean and renewable energy, the power shortage in the Gaza Strip and the limited number of wind energy studies conducted in the south coastal plain of Palestine, especially Gaza Strip. This study estimates the wind energy potential of the Gaza Strip to determine the wind potential. The annual mean wind speed and power are 4.11 ms-1 and 903.4 Wm-2, respectively. Moreover, the study clarifies the electrical energy generation in the Gaza Strip using small-scale turbines and offers a feasible alternative to existing schemes.

Dynamic Management of Water Storage for Flood Control in a Wetland System: A Case Study in Texas

In this study, we assess the costs and benefits of dynamic management of water storage to improve flood control in a system of wetlands. This management involves releasing water from wetlands ahead of (e.g., a few hours or days before) a rainfall event that is forecasted to produce flooding. Each project site may present different challenges and topographical conditions, however as long as there is a relatively small hydraulic gradient between the wetland water surface and the drainage ditch (e.g., >0.9 m), wetlands can be engineered for the purpose of flood control. We present a case study for a system comprised of four wetland areas encompassing 925 acres in the coastal plain south of Houston, Texas. The benefit–cost analysis shows that, in general, the benefits of wetland ecosystems far surpass the costs of construction and maintenance for all considered periods of analysis and assumed degrees of dynamic management of wetland storage. The analysis also shows that the benefit/cost ratios increase over the period of analysis. Considering flood protection only (e.g., not considering the value of other ecosystem services), as long as dynamic management of wetland storage increases flood protection by about 50% compared to that with no management (e.g., a typical wetland with no controlled release of water), the construction of a wetland system would have a benefit/cost ratio of at least 1.9.

Holocene Surface Ruptures on the Salinas Fault and Southeastern Great Southern Puerto Rico Fault Zone, South Coastal Plain of Puerto Rico

Holocene Surface Ruptures on the Salinas Fault and Southeastern Great Southern Puerto Rico Fault Zone, South Coastal Plain of Puerto Rico

Origin of groundwater salinity and hydrochemical processes in an unconfined aquifer: case of Yang-Dai River basin in Qinhuangdao (China)

Groundwater salinization has become a growing concern in Yang-Dai River basin of Qinhuangdao (China) where groundwater is commonly exploited for domestic, industrial and agricultural uses. In this study, hydrochemical and physical parameters of groundwater were analyzed to identify the origin of groundwater salinity and the geochemical processes occurring in the unconfined aquifer. Groundwater types are Ca·Mg–HCO3·SO4 in the hills, Ca·Mg–HCO3·SO4 in the piedmont plain and Na–Cl in the coastal alluvial plain, respectively. Electrical conductivity values varied between 322 and 3990 μS/cm. Chloride concentration attained to 942 mg/L and the proportion of seawater intrusion in the coastal alluvial plain was 5.39 % calculated by seawater fraction formal, displaying the severe seawater intrusion. Cation-exchange reactions and water–rock interactions related to the dilution of halite, gypsum, dolomite and calcite occurred by ionic relationships during seawater intrusion. High nitrate concentrations ranged from 35.6 to 686.5 mg/L distributed in the hills and the south coastal alluvial plain where they are seriously polluted by the industrial wastewater, agricultural fertilizers and domestic sewage. Seawater intrusion and nitrate contamination have common effects on the hydrochemical process in the south coastal alluvial plain. Therefore, the origin of groundwater salinization was attributed not only to seawater intrusion but also to anthropogenic pollution in the study area. This research provides useful information for groundwater salinization and water planning strategies in a coastal area.

Invertebrados aquáticos associados a serapilheira de Salix humboldtiana em um riacho subtropical

Ecología Austral 24:220-228 (2014)Allochthonous material from riparian forest is an important source for detritivore food chain in streams. This study aimed to: i) estimate the leaf mass loss of Salix humboldtiana Willd., ii) analyze the changes in the detritus chemical composition during mass loss, and iii) analyze the invertebrate colonizers assemblage of a sandy stream in south coastal plain of the Rio Grande do Sul state (Brazil). We hypothesized that S. humboldtiana debris constitute favorable habitat for colonization by invertebrates, which in turn contribute to debris degradation. Twenty eight bags were incubated on the sediment surface of the stream in seven sampling dates. During the decomposition process we analyzed changes of detritus chemical composition and the abundance, richness and functional trophic groups of invertebrates. After 184 days we recorded an average loss of 70% of debris (k=0.0066 day-1) and counted a total of 14197 invertebrate individuals, distributed in 36 taxa. Oligochaeta (43.6%), Hydrobiidae (16.6%), Chironominae (11.3%) and Hydracarina (6.6%) were the most representative. The biofilm development, observed through increased concentrations of total phosphorus and nitrogen in the debris, may have favored colonization by scrapers at the end of the decomposition period. The initial hypothesis was partially corroborated as the abundance of potential shredders was low, the contribution of invertebrates assemblage to litter decomposition was low, and the gathering-collectors were the most abundant group.

Field evidence of the influence of aquatic macrophytes on water quality in a shallow eutrophic lake over a 13-year period

AIM: The main objective of this work is to describe the changes in water characteristics of a shallow subtropical lake, in periods with and without growing of macrophytes, related to periods of clear-macrophyte dominance and turbid-phytoplankton dominance states. METHODS: The study was conducted in Biguás Lake, in the south coastal plain of Brazil (32° 04' 43" S and 52° 10' 03" W). Samplings were carried out monthly between October 2000 and November 2013. The limnological variables measured in the water column were dissolved oxygen (DO), water temperature, pH, electrical conductivity (EC), chlorophyll-a, total nitrogen (TN), total phosphorous (TP) and suspended material (SM). Data were grouped according to periods with macrophyte growth dominance (MD) and without macrophytes, with phytoplankton dominance (PD), and applied t- tests among TP, TN, Chlorophyll-a and SM. During macrophyte growth we estimated the coverage (%) and biomass variation of plants. RESULTS: Over the 13 years, the lake was well oxygenated, alkaline, and with a temperature variation according to subtropical seasonality. The lower values of all of the limnological variables were verified during periods of macrophyte growth, characterizing periods of clear and turbid waters. CONCLUSIONS: The influence of aquatic macrophytes in improving water quality in this shallow lake during the studied period, reducing nutrient concentrations, chlorophyll-a and suspended material in water, favoring the maintenance of a clear water state, was verified.

Differential effects of abiotic factors and host plant traits on diversity and community composition of root-colonizing arbuscular mycorrhizal fungi in a salt-stressed ecosystem

Arbuscular mycorrhizal fungi (AMF) were investigated in roots of 18 host plant species in a salinized south coastal plain of Laizhou Bay, China. From 18 clone libraries of 18S rRNA genes, all of the 22 AMF phylotypes were identified into Glomus, of which 18 and 4 were classified in group A and B in the phylogenetic tree, respectively. The phylotypes related to morphologically defined Glomus species occurred generally in soil with higher salinity. AMF phylotype richness, Shannon index, and evenness were not significantly different between root samples from halophytes vs. non-halophytes, invades vs. natives, or annuals vs. perennials. However, AMF diversity estimates frequently differed along the saline gradient or among locations, but not among pH gradients. Moreover, UniFrac tests showed that both plant traits (salt tolerance, life style or origin) and abiotic factors (salinity, pH, or location) significantly affected the community composition of AMF colonizers. Redundancy and variation partitioning analyses revealed that soil salinity and pH, which respectively explained 6.9 and 4.2 % of the variation, were the most influential abiotic variables in shaping the AMF community structure. The presented data indicate that salt tolerance, life style, and origin traits of host species may not significantly affect the AMF diversity in roots, but do influence the community composition in this salinized ecosystem. The findings also highlight the importance of soil salinity and pH in driving the distribution of AMF in plant and soil systems.

Curve Number Derivation for Watersheds Draining Two Headwater Streams in Lower Coastal Plain South Carolina, USA

AbstractThe objective of this study was to assess curve number (CN) values derived for two forested headwater catchments in the Lower Coastal Plain (LCP) of South Carolina using a three‐year period of storm event rainfall and runoff data in comparison with results obtained from CN method calculations. Derived CNs from rainfall/runoff pairs ranged from 46 to 90 for the Upper Debidue Creek (UDC) watershed and from 42 to 89 for the Watershed 80 (WS80). However, runoff generation from storm events was strongly related to water table elevation, where seasonally variable evapotranspirative wet and dry moisture conditions persist. Seasonal water table fluctuation is independent of, but can be compounded by, wet conditions that occur as a result of prior storm events, further complicating flow prediction. Runoff predictions for LCP first‐order watersheds do not compare closely to measured flow under the average moisture condition normally associated with the CN method. In this study, however, results show improvement in flow predictions using CNs adjusted for antecedent runoff conditions and based on water table position. These results indicate that adaptations of CN model parameters are required for reliable flow predictions for these LCP catchments with shallow water tables. Low gradient topography and shallow water table characteristics of LCP watersheds allow for unique hydrologic conditions that must be assessed and managed differently than higher gradient watersheds.

Fungos, criptógamas e outros palinomorfos holocênicos (7908±30 anos AP-atual) da Planície Costeira sul-catarinense, Brasil

Neste estudo são apresentados os resultados palinológicos qualitativos equivalentes às análises paleoambientais realizadas em duas seções turfáceas na Planície Costeira sul do estado de Santa Catarina, nos municípios de Santa Rosa do Sul e São João do Sul. Uma amostra da base do testemunho de Santa Rosa do Sul foi datada (14C) em 7908±33 anos AP, referente ao Holoceno inferior. A análise palinológica permitiu identificações taxonômicas, com descrições e ilustrações de 54 palinomorfos, relativos a fungos (21), algas (5), acritarcas (1), incertae sedis (1), briófitos (2), pteridófitos (15), pólen de gimnospermas (2), e outros palinomorfos (1 cápsula de briófitos, 4 fragmentos de invertebrados e 2 palinoforaminíferos indeterminados), cujos registros modernos expressam diferentes hábitos de vida. O trabalho tem como objetivos contribuir para o conhecimento dos vestígios da vegetação e táxons relacionados depositados na Planície Costeira sul-catarinense durante o Holoceno. As análises palinológicas conseguintes auxiliarão na interpretação dos paleoambientes e paleoclimas relacionados neste setor da costa brasileira.

The color reflectance of marine-terrigenous deposits in LZ908 borehole in south coastal plain of the Laizhou Bay

Color measuring is characterized by high resolution, high efficiency, and low cost. The application becomes increasingly common for tracing sediment sources and climate variation. Borehole LZ908 in the south coastal plain of the Laizhou Bay in northeast China, was used, of which the top 54 m containing all marine facies was focused, to test the feasibility of colorimetry as a climate indicator using visible light reflectance spectra and L*a*b* measurement results. The results show a good correction between lightness and calcium carbonate content in marine-terrigenous deposits; therefore, these deposits can be used as a proxy to study climate changes. Factor-analysis on the first derivative values of the raw visible light reflectance spectra produced three principal factors corresponding to goethite, organic matter, and hematite. Down hole variations in the three factor scores, lightness, calcium carbonate content, and grain size were quite consistent. Moreover, high lightness and low factor scores in goethite, hematite, and organics indicated glacial regression deposits, while low lightness and high factor scores in goethite, hematite, and organics indicated interglacial transgression deposits.

Economic Analysis of Conservation Forestry Practices: a South Carolina Lowcountry Example

Abstract The Lowcountry Forest Conservation Project was designed to encourage conservation forestry practices on South Carolina's lower coastal plain. The area has great ecological diversity and need for the type of protections afforded by conservation forestry. The project provided demonstrations of these practices and offered forest owners an estimate of the cost-effectiveness of the techniques. This article reports on a financial analysis of the three main practices: (1) the reintroduction of longleaf pine (Pinus palustris P. Miller) into areas that are now loblolly pine plantations (Pinus taeda L.), (2) more and better use of prescribed fire, and (3) bottomland hardwood management. Longleaf pine reintroduction was accomplished using partial clearcuts of existing pine plantations over several decades. Financial return was shown to be competitive with intensively-managed loblolly pine plantations. Pine straw production played a large role in increasing cash flows. Prescribed burning was shown to “pay fo...

Environmental evolution in the salt-water intrusion area south of Laizhou Bay since late Pleistocene

The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses of pollen, foraminifera and grain size com-position based on 14C and luminescence dating from two sediment cores were performed for the purpose of understanding the salt-water intrusion in the coastal plain of Laizhou Bay from the perspective of environmental evolution since late Pleistocene. It could be classified into seven evolution stages since 120 kaBP: 120-85 kaBP was a transition period from cold to warm; 85-76 kaBP was a period with warm and wet climate having swamp lakes developed in the lower reaches of the Weihe River, south coastal plain of Laizhou Bay; 76-50 kaBP was characterized by grassland vegetation and coarse sediments in terrestrial environment, which was the early stage of Dali Ice-Age; 50-24 kaBP was a period with alternate sea deposition in the south coastal plain of Laizhou Bay; 24-10 kaBP was the late stage of Dali Ice-Age with coldest period of Quaternary, the south coastal plain of Laizhou Bay was dry grassland and loess deposition environment; 10-4 kaBP was another warm and wet climate period, sea level was high and regressed at 4 kaBP; and has been the modern sedimentary environment since 4 kaBP. Among the three warm stages, including 85-76 kaBP, 50-24 kaBP and 10-4 kaBP, corresponded to late Yangkou, Guangrao and Kenli seawater transgression respectively. The duration of the latter one in south coastal plain of Laizhou Bay was longer than that in west coast of Bohai Sea and east coast of Laizhou Bay. The three periods of seawater transgression formed the foundation of salt-water intrusion in this area.

Grass assemblages and diversity of conservation areas on the coastal plain south of Maputo Bay, Mozambique

A floristic analysis of the grass species assemblages of the Licuati Forest and Maputo Elephant Reserves south of Maputo Bay, Mozambique, is presented. Sampling of grass data was undertaken in six previously described, major vegetation types. TWINSPAN divisions distinguished grass assemblages that are characteristic for these major vegetation types of the study area. The results were supported by an Indirect Gradient Analysis. Further TWINSPAN divisions of a larger Maputaland data set indicated a floristic relationship between grass assemblages of similar major vegetation types in the study area and South Africa. This relationship was supported by high similarity values ( 65%), obtained with Sorenson's Coefficient. The coefficient also indicated varying degrees of similarity between grass assemblages of different major vegetation types within the study area. A rich diversity of 115 grass species and infraspecific taxa was recorded for the study area. The Chloridoideae and Panicoideae dominate the grass diversity and the genera with the most species include Eragrostis, Panicum and Digitaria. Most grass species in the study area are perennials and have a tufted growth form, but this varies considerably between vegetation types.

August 8, 1993 Aiken, South Carolina Earthquake

An analysis of collected data are presented for an m bLg 3.2 earthquake that occurred on August 8, 1993 approximately 15 km northeast of Aiken, South Carolina. A maximum intensity of IV (MM) was experienced near the small community of Couchton, South Carolina. Isoseismals seemed to mostly follow a northeast-southwest trend. One small aftershock occurred approximately six and one-half hours after the main event and was located coincident with it. A focal mechanism was derived using 18 impulsive P-wave first motions of local and regional stations indicating predominantly strike-slip motion on a southeast striking plane dipping 60° to the southwest. The event was not associated with established seismogenic zones of South Carolina but was characteristic of occasional strain release that occurs in broad regions of the South Carolina Piedmont. The event and its aftershock, while not particularly large or unusual for the South Carolina Central Piedmont and upper Coastal Plain, contribute background information and data for the historical record.

Susceptibility of Plant Species in Banksia Woodlands on the Swan Coastal Plain, Western Australia, to Infection by Phytophthora cinnamomi

Estimates of the susceptibility of plant species in Banksia woodland to Phytophthora cinnamomi Rands were obtained by determining the incidence of plant death and frequency of isolation of the pathogen, among species occurring in 46 disease centres on the Swan Coastal Plain south of Perth, Western Australia. In the disease centres, dicotyledons outnumbered monocotyledons. About half of all species occurring in the disease centres were from four families of dicotyledons, with the largest number of species from the Myrtaceae, Proteaceae and Papilionaceae. The greatest number of species of monocotyledons were from the Anthericaceae and Cyperaceae. No deaths were recorded for 47% of species found in three or more disease centres. These species were mainly from the Cyperaceae, Haemodoraceae, Myrtaceae and Papilionaceae. The species that tended to die frequently in disease centres were mainly from the Papilionaceae, Proteaceae, Epacridaceae, Xanthorrhoeaceae and the Zamiaceae. Phytophthora cinnamomi was isolated from 26 of the 95 species occurring in three or more disease centres. For most species, the frequency of isolation of P. cinnamomi from recently dead plants was much less than the frequency of dead plants sampled. Isolation from plants was less frequent than from adjacent soil. The pathogen was isolated from recently dead plants or soil mainly for species of the Proteaceae, Myrtaceae, Papilionaceae, Dasypogonaceae, Iridaceae and Xanthorrhoeaceae. Cross-tabulation of species by incidence of plant death and isolation of P. cinnamomi from plant and soil, provided the opportunity to classify the response of plant species to infection by P. cinnamomi.

Taxation in the amirate of Mecca during the medieval period

The amirate of Mecca was established by sharifs of Hasanid ancestry in the middle of the fourth century a. h./tenth century a.d. The territory traditionally under its direct control included the holy city of Mecca and its immediate hinterland, the nearby hill town of Ṭā'if, and the Red Sea port of Jedda. In addition, the sharifs often exercised a tenuous hold over certain tribal areas in the Sarāt Mountains south of Ṭa'if, as well as the coastal plain south of Jedda, known as the Tihāma.

Patriarch Poppo (1019–1042) and the Rebuilding of the Basilica at Aquileia: the Politics of Conspicuous Expenditure

The traveller between Venice and Trieste may, if he knows where to look, catch a glimpse of a rather aggressive campanile in the coastal plain south of Cervignano. Slightly detached from the great basilica of Aquileia, rebuilt and then dedicated in 1031, the campanile was almost certainly intended by its builder, the Patriarch Poppo, as a gesture of derision towards its contemporary counterpart in Venice. With its foundations firmly skewering an Early Christian mosaic floor, it today overlooks a farmyard midden, the skeletal remains of a huge Roman city, and, of course, the splendid basilica.

The Late Quaternary history of climate and vegetation in East and southern Africa

In the vast region of East and southern Africa the alternating glacial and interglacial periods of the Quaternarv were characterized by considerable changes in temperature and precipitation. During the last glacial maximum the influence of the ITCZ was limited, while the circulation systems were strengthened. The ocean surface waters were cooler and the Benguela Current was activated. In the montane areas of East Africa and also in southern Africa the temperature dropped by about 6°C. During this hypothermal period, rainfall on the east African plateau and mountains diminished. Summer precipitation could still penetrate the eastern half of southern Africa from the Indian Ocean, while the western half was arid to semi-arid. Cyclonic winter rain migrated further north beyond the latitude of the Orange River. The consequences of these climatic changes during the last glacial maximum were that the woodlands of East Africa opened up. On the plateau of South Africa austro-afroalpine vegetation dominated. The south coastal plain was very windy and cold to temperate, while the Namib and Kalahari were respectively hyper-arid and semi-humid. During hyperthermals the vegetation pattern resembled present-day conditions more closely.

Determination of the mechanism of recharge in the Los Naranjos Area in Mexico using environmental isotope techniques

The Río Blanco crosses a coastal plain south of Veracruz in Mexico, and discharge measurements suggested that the river was recharging the groundwater system. The estimated evapotranspiration is very close to the mean annual precipitation, so estimates of effective recharge by infiltration of precipitation are very imprecise. The variations in the stable isotopic composition (D and 18O) of surface and groundwater samples are used to estimate the relative importance of the two sources of recharge to the groundwater system. The data indicate that recharge by infiltration of precipitation is the dominant source of recharge. This conclusion is based upon measurements from individual wells and also on the base flow of rivers originating in the plain, thus providing an estimate integrated over the area drained by the rivers.