Heavy metals,polycyclic aromatic hydrocarbons and organochlorine pesticides in the surface sediments of mangrove swamps from coastal sites along the Leizhou Peninsula,South China

Contents of heavy metals, polycyclic aromatic hydrocarbons （PA Hs）, dichlorodiphenyltrichloroethanes （DDTs） and hexachlorcy- clohexanes （HCHs） in surface sediments from mangrove areas of the Leizhou Peninsula were analyzed in July and November 2005. Risk assessment criteria applied by Long E R et al. （1995） and Long E D et al. （1995） （effects range low, ERL; effects range mean, ERM） of chemicals in sediments from the gulf or estuary were used to assess the potential ecological risks of heavy metals, PAHs, DDTs and HCHs to aquatic organisms in the studied area. The results indicated that the average contents of zinc, nickel, chromium, lead, copper, arsenic and mercury were （61.97 ± 55.87）, （59.99 ± 39.01 ）, （47.93 ± 28.37）, （26.64± 13.00） , （23.45 ± 41.96）, （9.32 ± 3.62）, （0.14 ± 0.18） mg/kg in dry weight in the sediment samples col- lected from five studied sites in the Leizhou Peninsula, respectively. Cadmium was not calculated due to its content being below the detection limit （ 〈 0.3 mg,/kg）. The average levels of Cr, Cu, Ni, Pb, Zn and Hg exceed their background values. The average contents of Ni were higher than ERM. The contents of PAHs in the sediments from the five studied sites were （79.78 ± 43.70） ng/g in dry weight, far lower than ERL（4 022 ng/g）. The contents of DDE, DDD and DDTs in the sediments from five studied sites were （2.60 ± 4.68）, （ 17.52 ± 27.25 ）, （27.78 ± 46.64） ng/g in dry weight respectively, clearly higher than ERL, and the average contents of DDT were （7.66 ± 15.93） ng/g in dry weight, much higher than ERM. HCHs could be detected in the sediments only from Gaoqiao sampling site, with the average contents （0.07 ± 0.08） ng/g in dry weight.

Impact of climate change on dynamic of plant communities, lakes and swamps in Beijing area during Holocene period

From 400-60 cm 26 samples were obtained in an 820 cm profile at Dongganchi of Fangshan in Beijing. They provided a continuous record of vegetation and environmental changes over ca .7000 aB.P., as inferred from Spore-pollen. loss-on-ignition (LOI), and charcoal analysis,impacts of natural fire and human activities on plant communities and lakes and swamps were considered. 1) From 7000-5960 aB.P, the forest development was limited, probably in response to climate Warming. Aquatic and marsh plants began to increase, bat the lakes and swamps in some areas were limited. 2) About 5960-3390 aB.p, presumably in responded to climate warming which was warmer than that at present Aquatic plants began to become abundant,reflected the widespread development of the lakes and swamps, the climate was wet with annual precipitation higher than that at present 3) About 3390-1000 aB.P, human activities have kept to be the dominating factor in the evolution of vegetation and climatic change. Temperature decreased, and the annual precipitation rapidly reduced in Baijing area. the lakes and swamps gradually shrank back, some of them even disappeared. 4) After 1000 aB.P, there was a severe fluntuction, and early during this time, it was comparatively warm and humid, but became cool and dry later. In the meantime. human activities were intensified. agricultural activity was flourished. and large area of water field was cultivated

Morphometric relationships and reproductive maturation of the mudskipper, Periophthalmus barbarus from subsistence catches in the mangrove swamps of IMO estuary, Nigeria

From April 1992 and March 1993, morphometric characteristics and reproductive maturation were studied in Periophthalmus barbarus from subsistence catches in the mangrove swamps of Imo estuary. Morphometric equations for males and females at different stages of ovarian maturation are presented. Generally males were significantly heavier in weight than females, but the latter were heavier than the former of the same body length. Females with developing and mature ovaries were generally heavier than immature females of the same length. Analyses of the gonadosomatic index and percentage of mature males and females indicate all year\|round breeding such that: February\|May was spawning, June\|October postspawning and November to January recovery period. Fecundity varied between 900 and 23933 eggs per spawn and increased with fish size.

Isolation of Marine Actinomycetes from the Mangrove Swamps for Biotechnological Exploration

The mangroves are specialized marine environments widely distributed along the coast lines, which support biologically diverse groups of organisms including microbes. The microorganisms present in this ecosystem contribute significantly in the food web of the tropical marine ecosystem. In the present investigation, Actinomycete isolates obtained from mangrove sediments have been studied for diversity as well as for their bioactive potential. Seven different Actinomycete isolates （MS 1-MS7） were obtained from the sediments collected from the mangrove swamps. The phylogenetic analysis of these isolates showed that out or seven isolates, 3 isolates belong to Streptomyces sp., which has bioactive potential as several bioactive metabolites have been isolated from this group. One bacterium showed genetic similarity with Corynebacterium sp.. The microbes from this group are used for very important industrial applications. Three Actinomycete isolates showed very low similarity with the reported strains from the gene bank. In suggests that, these cultures could be novel and further research work is warranted to prove this speculation. In antagonistic studies, three Actinomycete isolates showed promising results. This investigation highlights the importance of mangrove ecosystem as a rich source of diverse Actinomycete strains for biotechnological applications.

A Field Study in the Status and Threats of Cultivation in Kimana and Ilchalai Swamps in Amboseli Dispersal Area, Kenya

The scarcity of water and dependence of local communities on wetlands for resources and services is a common occurrence in dry rangelands such as Amboseli in Kenya. There are only a few swamps outside Amboseli National Park available to the Maasai, livestock and wildlife. Such swamps may disappear in the near future because of conversion to cultivation. This study established the current size and threats to Kimana and Ilchalai near Amboseli National Park. Swamps were regularly used by over 15 large mammal species among them elephants, buffalo, wildebeest, zebra, gazelles and hippopoatums. However, only 15.7% of Kimana Swamp and 36.1% of Ilchalai Swamp remained unconverted to cultivation, with the rest of the remaining swamp area converted to agriculture. Cultivation was mainly done by non–Maasai land leasers, and for mainly commercial purposes. Swamps were converted because of adequate and free water, cheap lease fee, and their fertile soils. Although concerned with swamp conversion, most cultivators were ready to expand cultivation in other swamps. These findings demonstrate how unsustainable resource use and swamp conversion can seriously threaten critical resources for local livelihoods and wildlife conservation.

COASTAL SALT MARSHES AND MANGROVE SWAMPS IN CHINA

Based on plant specimen data,sediment samples,photos,and sketches from 45 coastal cross-sections,and materials from two recent countrywide comprehensive investigations on Chinese coasts and is-lands,this paper deals with China’s vegetative tidal-flats:salt marshes and mangrove swamps.Thereare now 141700 acres of salt marshes and 51000 acres of mangrove swamps which together cover about30% of the mud-coast area of the country and distribute between 18°N(Southem Hainan Island)and41°N(Liaodong Bay).Over the past 45 years.about 1750000 acres of salt marshes and 49400 acres ofmangrove swamps have been reclaimed.The2.0×10~9 tons of fine sediments input by rivers into the Chinese seas form extensive tidal flats,the soil basis of coastal helophytes.Different climates result inthe diversity of vegetation.The 3～8m tidal range favors intertidal zone development.Of over 20plant species in the salt marshes,native Suaeda salsa,Phragmites australis,Aeluropus littoralis,Zoysiamaerostachys,Imperata cylindrica and

Peat swamps at Giral lignite field Western India： understanding the modelling of Barmer basin, Rajasthan, evolution through petrological

The lignite samples collected from Giral lignite field of Barmer basin have been subjected to petrological investigation. The data generated has been discussed to understand the evolution of the paleomires of these lignites. The present study reveals that these low rank C coals are chiefly composed of huminite group macerals, mainly telohuminite and detrohuminite, while liptinite and inertinite group macerals occur in subordinate amounts. Not much variation in the maceral composition from Seam-I to Seam-VIII has been observed. Barmer lignites are characterized by a very high GI （〉10） and moderate TPI indicating topogenous mire in the basin which was permanently flooded. The GI and TPI values and the petrography-based facies critical models indicate that these lignites originated mostly under wet forest swamp to clastic marsh having telmatic to limno-telmatic conditions with a moderate rate of subsidence and a very slow fall in ground water table. Further, the GWI and VI values are suggestive of mesotrophic to rheotrophic hydrological conditions having the dominance of herbaceous to marginal aquatic vegetation. There were spells of periodic drowning of peat especially during the formation of Seam-VII. Moderately high concentration of calcium in these lignites along with the presence of framboidal pyrite indicate enhanced sulphate-reducing bacterial activity present in carbonate and sulphate-rich waters in the basin during peat formation.

Intersexual plasticity in aspects of the biology of the mudskipper Periophthalmus barbarus (Gobhdae) in the mangrove swamps of IMO Estuary, Nigeria

Between April 1992 and March 1993, intersexual plasticity in aspects of the biology of the mudskipper, Periophthalmus barbarus was studied. Sex was differentiated on the basis of the genital papillae, it was broader in females than males. Sexually active females were slightly heavier than similarly sized males. Sex ratio was strongly female biased. Length weight relationship of the sexes was isometric. There was no significant difference in the feeding intensity of both sexes; uniformity was also apparent in diet breadth. There was no named sex based difference in hepatosometic index but condition index was higher in males than females. The uniformity in intersexual plasticity of P.barbarus is consequent upon homogeneity of the mangrove ecosystem, which can only be altered anthropogenically.

Trophic attributes of the mudskipper, Periophthalmus barbarus (Gobiidae: Oxudercinae) in the mangrove swamps of Imo River Estuary, Nigeria

Aspects of the trophic attributes of the mudskipper, Periophthalmus barbarus occurring in the mangrove swamps of Imo River Estuary, Nigeria, were investigated during a 12 month period (April, 1992\_March, 1993). Feeding intensity increased with size, it was higher in the dry season(November\_April) than in the wet season(May\_October), monthly changes in the indices of feeding intensity were significantly correlated. Major food objects comprised detritus and benthic algae; crustaceans, insects, macrophyte matter and sand grains were minor food objects while fish, molluscs, Chilopoda, nematodes and fungi were unconsciously devoured objects. Diet varied seasonally; algae and sesarmid crabs were generally more in the dry season than during the rains whereas FPOM and fish increased in the wet over dry season. The mudskipper display a high degree of euryphagy and can be considered as a generalist and an omnivore. The lower trophic status of P. barbarus qualifies it as a good aquaculture candidate. Food richness was higher in big sized class(BSC) than small sized class(SSC). Size based and seasonal variations were not apparent in food richness. Diet breadth was higher in the BSC than the SSC, there was dry season increase in diet breadth.

CELLULOSE DECOMPOSTION IN TROPICAL PEAT SWAMPS

Given that organic soil is a complex substrate and there are many environmental factors which directly or indirectly control its decomposition processes, the use of standard substrate simplify the system in that the effect of substrate quality could be eliminated and influence of certain environmental conditions such as edaphic factors, acidity and moisture could be focused on. In addition to the forest floor, decomposition potential down the peat profile can also be examined. Cotton strip assay was used to estimate decomposition potentials in tropical peat swamp occupied by different Shorea Albida peat swamp forest communities, The' Alan Batu' , the ' Alan Bunga' , the' Alan Padang' and the 'mixed Alan'forest communities. Greatest decay rates on the peat surface took place during the wet period. The moist condition of the wet months appeared to favour the growth and stimulate activities of decomposer population and soil invertebrates.Generally, 50% of cotton tensile loss is achieved after four weeks of exposure. The results suggest that cellulose decomposition is influenced by the environmental variables of hydrological regime, water-table fluctuation, aeration, moisture availability,waterlogging and the resultant anaerobiosis, peat depths, and micro-sites characteristics. Decomposition of cellulose is inhibited by waterlogging and the resultant anaerobiosis in thelower segment of the cotton strip during wet periods and under dry conditions in the surface segment of the cotton strip during periods of less rain.

Mapping Deciduous Broad-leaved Forested Swamps Using ALOS/Palsar Data

Accurate, updated information on the distribution of wetlands is essential for estimating net fluxes of greenhouse gases and for effectively protecting and managing wetlands. Because of their complex community structure and rich surface vegetation, deciduous broad-leaved forested swamps are considered to be one of the most difficult types of wetland to classify. In this research, with the support of remote sensing and geographic information system, multi-temporal radar images L-Palsar were used initially to extract the forest hydrological layer and phenology phase change layer as two variables through image analysis. Second, based on the environmental characteristics of forested swamps, three decision tree classifiers derived from the two variables were constructed to explore effective methods to identify deciduous broad-leaved forested swamps. Third, this study focused on analyzing the classification process between flat-forests, which are the most severely disturbed elements, and forested swamps. Finally, the application of the decision tree model will be discussed. The results showed that: 1) L-HH band(a L band with wavelength of 0–235 m in HH polarization mode; HH means Synthetic Aperture Radars transmit pulses in horizontal polarization and receive in horizontal polarization) in the leaf-off season is shown to be capable of detecting hydrologic conditions beneath the forest; 2) the accuracy of the classification(forested swamp and forest plat) was 81.5% based on hydrologic features, and 83.5% was achieved by combining hydrologic features and phenology response features, which indicated that hydrological characteristics under the forest played a key role. The HHOJ(refers to the band created by the subtraction with HH band in October and HH band in July) achieved by multi-temporal radar images did improve the classification accuracy, but not significantly, and more leaf-off radar images may be more efficient than multi-seasonal radar images for inland forested swamp mapping; 3) the lower separability between forested swamps dominated by vegetated surfaces and forest plat covered with litter was the main cause of the uncertainty in classification, which led to misleading interpretations of the pixel-based classification. Finally, through the analysis with kappa coefficients, it was shown that the value of the intersection point was an ideal choice for the variable.

Lead Accumulation in Tidal Swamps:Case Study at Transmigration Area of South Sumatra Indonesia after 40 Years Cultivation

Lead(Pb)is a heavy metal that poses a major hazard to animals and humans when consumed.The content of this metal is significantly high in paddy soil due to the residual effect of phosphate fertilizer.Therefore,this study aims to determine the Pb content in the tidal swamp that has been used for agriculture for 40 years.It was carried out from October 2021 to January 2022 on tidal soils representing land typology of A,B,C,and D distributed in the Transmigration area of Mulia Sari,Tanjung Lago District,Banyuasin Regency of South Sumatra,Indonesia.A detailed survey was used and soil samples were taken from up to 12 soil sampling points.The variables observed were soil Pb,pH,CEC(Cation Exchange Capacity),pyrite,and C-organic.The results showed that the Pb content in tidal soils obtained was varied,namely 22.52 mg/kg,14.84 mg/kg,16.84 mg/kg,and 16.68 mg/kg for A,B,C,and D type of land typologies,respectively.Based on these values,the Pb accumulation has exceeded the threshold,which is 12.75 mg/kg.

Highlighting relationships between sand thicknesses,reservoir-seal pairs and paleobathymetry from a sequence stratigraphic perspective:An example from Tortonian Serravallian deposits,onshore Niger Delta Basin

The utilization of sequence stratigraphic concepts in identifying sands and their spatial continuity in distinct gross depositional settings is key,especially in frontier settings where data paucity is a common challenge.In the Baka field,onshore Niger Delta,detailed reservoir correlation guided by sequence stratigraphic framework analysis showed the distribution of sand and shale units constituting reservoirseal pairs(RSP)correlatable across the field.Within the 3rd-order packages,it is observed that the lowstand systems tract(LST)and highstand systems tract(HST)contain more RSPs and thicker 4th-and 5th-order sands than the transgressive systems tract(TST).In terms of bathymetry,it is noted that irrespective of systems tracts,the RSP Index(RI)decreases from the proximal shallow/inner shelf settings to the more distal outer shelf areas.Amongst all three systems tracts,intervals interpreted as lowstand prograding complexes contain the best developed sands and highest RSP.Sand development within the LSTs has been controlled by a pronounced growth fault regime accompanied by high subsidence and sedimentation rates.This is linked to the basinward migration of the sands during prolonged sea-level fall,creating significant accommodation space for sand deposition.On the other hand,the TSTs known to mark periods of progressive sea-level rise and landward migration of sandy facies,show thinner sands enclosed in much thicker,laterally extensive,and better-preserved deeper marine shales.Interpreted seismic sections indicate intense growth faulting and channelization that influenced the syn-and postdepositional development of the sand packages across the field.The initial timing of deformation of subregional faults in this area coincides with periods of abrupt falls in sea level.This approach could be useful for predicting sand-prone areas in frontier fields as well as possible reservoir-seal parameters required for some aspects of petroleum system analysis and quick-look volume estimation.

A Metadata Reconstruction Algorithm Based on Heterogeneous Sensor Data for Marine Observations

Vast amounts of heterogeneous data on marine observations have been accumulated due to the rapid development of ocean observation technology.Several state-of-art methods are proposed to manage the emerging Internet of Things(IoT)sensor data.However,the use of an inefficient data management strategy during the data storage process can lead to missing metadata;thus,part of the sensor data cannot be indexed and utilized(i.e.,‘data swamp’).Researchers have focused on optimizing storage procedures to prevent such disasters,but few have attempted to restore the missing metadata.In this study,we propose an AI-based algorithm to reconstruct the metadata of heterogeneous marine data in data swamps to solve the above problems.First,a MapReduce algorithm is proposed to preprocess raw marine data and extract its feature tensors in parallel.Second,load the feature tensors are loaded into a machine learning algorithm and clustering operation is implemented.The similarities between the incoming data and the trained clustering results in terms of clustering results are also calculated.Finally,metadata reconstruction is performed based on existing marine observa-tion data processing results.The experiments are designed using existing datasets obtained from ocean observing systems,thus verifying the effectiveness of the algorithms.The results demonstrate the excellent performance of our proposed algorithm for the metadata recon-struction of heterogenous marine observation data.

Key Techniques of an Ecological Pattern“Planting Rice in One Season and Breeding Red Swamp Crawfish in Three Seasons” for Green Production in Lixiahe Region of Jiangsu Province

Three big field projects, independent irrigation and drainage facilities, and a blocking net, which are auxiliary projects of a green planting and breeding pattern composed of rice and red swamp crawfish （Procambarus clarkii）, spatial and temporal coupling technology of ＂planting rice in one season and breeding red swamp crawfish in three seasons＂, green fertilization technology, green prevention and control technology, control technology of water level, and throwing technology of bait in Lixiahe region of Jiangsu Province were introduced successively, which can provide technical support for the development of ecological planting and breeding patterns and realization of green production in paddy fields.

指数分布场合下同时存在异常大和异常小值的检验

针对指数分布的场合 ,笔者从经典统计思想入手给出了”取中逐步推移检验法” 。

DNA Damage and Repair of Two Ecotypes of Phragmites communis Subjected to Water Stress

In order to thoroughly understand the mechanism Of drought resistance in plants at DNA level, the DNA damage of two ecotypes of reeds (Phragmites communis T.) stressed by PEG 6000 was analyzed by means of fluorescence analysis of DNA unwinding (FADU). The results showed that the residual double strand DNA percentages (dsDNA%) in dune reed (DR) were significantly higher than those in swamp reed (SR) treated with either 20% or 30% PEG 6000. This meant that the DNA of DR was less damaged in comparison with SR. Similarly, DR resisted DNA damage more strongly than SR as reactive oxygen species (ROS) increased by adding ROS producers diethyldithio carbamate (DDC), H2O2 and Fe2+ of different concentrations. Meanwhile, treating PEG stressed SR with ROS scavengers such as dimethyl sulphoxide (DMSO) and ascorbic acid (Vc) resulted in the reduction of DNA damage, suggesting that ROS could cause DNA damage. In addition, the DNA repair for water-stressed reeds indicated that DR repaired DNA damage much faster and more completely. This might be the first indication that drought stress led to DNA damage in plants and that drought resistance of plants was closely related to DNA damage and repair.

Mapping Sensitive Vegetation Communities in Mining Eco-space using UAV-LiDAR

Near earth sensing from uncrewed aerial vehicles or UAVs has emerged as a potential approach for fne-scale environmental monitoring.These systems provide a cost-efective and repeatable means to acquire remotely sensed images in unprecedented spatial detail and a high signal-to-noise ratio.It is increasingly possible to obtain both physiochemical and structural insights into the environment using state-of-art light detection and ranging(LiDAR)sensors integrated onto UAVs.Monitoring sensitive environments,such as swamp vegetation in longwall mining areas,is essential yet challenging due to their inherent complexities.Current practices for monitoring these remote and challenging environments are primarily ground-based.This is partly due to an absent framework and challenges of using UAV-based sensor systems in monitoring such sensitive environments.This research addresses the related challenges in developing a LiDAR system,including a workfow for mapping and potentially monitoring highly heterogeneous and complex environments.This involves amalgamating several design components,including hardware integration,calibration of sensors,mission planning,and developing a processing chain to generate usable datasets.It also includes the creation of new methodologies and processing routines to establish a pipeline for efcient data retrieval and generation of usable products.The designed systems and methods were applied to a peat swamp environment to obtain an accurate geo-spatialised LiDAR point cloud.Performance of the LiDAR data was tested against ground-based measurements on various aspects,including visual assessment for generation LiDAR metrices maps,canopy height model,and fne-scale mapping.

指数分布中下异常值的逐步检验的改进

关于指数样本中下异常值的检验，各种文献中仅对下异常值个数已知的情况作了讨论．当下异常值个数未知时，因存在ｍａｓｋｉｎｇ或ｓｗａｍｐｉｎｇ效应，检验问题变得十分复杂和困难．本文成功地解决了这一问题．

正态样本中多个异常值的双边检验(英文)

对于正态样本中上下异常值的同时检脸，大多数文献仅处理了下异常值的个数ｋ１和上异常值个数ｋ２已知的情况，当ｋ１和ｋ２未知时．由于受ｍａｓｋｉｎｇ或ｓｗａｍｐｉｎｇ效应，检验问题变得十分困难与复杂．本文成功地解决了这一问题．