Vegetation Formation in Estuarine Tidal Flats: Influences of Basin Scale and River-Crossing Structures of the Eight Rivers of Ise Bay in Mie and Aichi Prefectures, Japan

In this study, we examined the influences of the differences in basin scale and river-crossing structures of 8 rivers of Ise Bay in Mie and Aichi Prefectures, Japan on the vegetation in the estuarine tidal flats of these rivers. The dominant plant communities of the estuarine tidal flats formed from rivers of large-scale river basins (exceeding 300 km2) were determined. In the Miya River, the dominant plant community was the Suaeda maritima and Artemisia fukudo community. In the Kushida River, the dominant plant community was composed of Phacelurus latifolius, Artemisia fukudo, Phragmites australis, and bamboo. In the Kumozu River, the dominant community was composed of the coastal plants Calystegia soldanella, Lathyrus japonicus, and Carex pumila and the exotic plant of Lolium multiflorum. The plant community of Suzuka River was dominated by the exotic plant of Eragrostis curvula. Among the estuarine tidal flats influenced by a small-scale river basin (50 km2 or less), the plant community of Shinbori River (Fukue tidal flat) was dominated by Suaeda maritima, and the plant communities of the Shio and Harai Rivers were dominated by Phragmites australis. The plant community of Tanaka River was dominated by Phragmites australis and coastal plants. Regarding the relationship between the vegetation and the river environment for each study site, we hypothesised that in a large basin area with few structures crossing the river, the river water catchment in the estuary after heavy rains caused large areas of disturbance and formed bare land, providing suitable habitat for an annual salt marsh plant community. In contrast, in cases with many structures crossing the river, a stable channel, an excavated riverbed and the suppression of runoff and the resulting disturbance of the estuary, flooding did not occur during high tide. Moreover, we hypothesised that in a small basin with many structures crossing the river, disturbance to the estuary was not likely, and the perennial salt marsh plant community of Phragmites australis would be widely distributed, except for a river type such as the Shinbori River, in which tide and river flow were managed by a final closure.

Road Lateral Disconnection and Crossing Impacts in River Landscape of Lancang River Valley in Yunnan Province,China

Roads are conspicuous components in a river landscape;however,their impacts on river landscape patterns and ecological processes have not been systematically studied at the watershed scale.In this paper,the Lancang River Valley in Yunnan Province,China was selected as a case to study road lateral disconnection and crossing impacts and identify river-road network interaction.This study was primarily focused on the road impacts on soil erosion intensity and patch density by using GIS analysis at different scales and explored their distribution with terrain factors.The results showed that river density revealed spatial autocorrelation although both of the roads and rivers were distributed unevenly in the valley.The lateral road(road curvature≥1.1)proportion correlated with soil erosion intensity(p 0.01)at the small sub-basin scale.Soil erosion intensity decreased with increasing lateral road buffer width.Light erosion generally accounted for a large proportion of the erosion in the lateral road buffer zones(1.0–4.0 km),while higher class lateral roads imposed greater impacts on soil erosion than lower class roads,which primarily had a moderate erosion level.In addition,the results of road-river intersection density indicated that road crossing impacts were significantly correlated with patch density at the small sub-basin scale.Topography factor(percent of slope>25°in each sub-basin had a close relationship with the ratio of total length of road line with curvature value≥1.1 to the total number of intersections.The correlation(p 0.01)between road impacts and terrain factor revealed that topography affected the road impact distribution in the Lancang River Valley.

Load compensation research on twicetension for loop anchor cable of inner lining in Yellow River-crossing tunnel

The load compensation equipment for anchor cable named low retraction prestressed anchorage system with twice-tension(referred to as twice-tension anchorage system) is proposed in the paper. Calculation results of loop anchorage prestressing loss(PL) values of inner lining(IL)in Yellow River-crossing tunnel under two anchorage systems,including twice- tension anchorage system and HM(Chinese transliteration is huanmao)anchorage system,are introduced. The software ANSYS is selected to realize the three-dimensional(3D) finite element modeling to accomplish simulation and calculation works under the two anchorage systems,respectively. Stress processes of IL under the two working conditions,of which one is completed cable tensioning(CCT) and the other is water in the tunnel with the designed water pressure(DWP),are contrasted and analyzed. Impacts of prestressing forces of anchor cables on structural safety under the two anchorage systems are contrasted. The calculation results show that the twice-tension anchorage system can reduce PL effectively and then increase prestresses of wall concrete(WC). Meanwhile,the anchorage system has the advantages of improving security and stability of tunnel structure,reducing project costs and saving steel consumption. The research work is available to related design and construction of anchor cable,and is worthy of promotion and application.

On the National Symptoms of Boar Crossing the River:One Hundred Years of Solitude in a Malaysian Chinese Village

After the famous“Rainforest Trilogy”such as Monkey Cup and Elephants,Zhang Guixing,a Malaysian Chinese writer in Taiwan,recently published another Nanyang story Boar Crossing the River,in the background of anti-Japanese War,focusing on the massacres and resistance of the Chinese in Krokop,a Malaysian Chinese village in Borneo from 1941 to 1945 according to a list of“Committee for the Relief of Refugees of the Motherland”.In this novel,Zhang Guixing changes the accustomed narrative mode of individual family history,expands the description to the group images of the Chinese in Krokop,highlights their patriotic sacrifice,and saves the reality of the slaughter of the compatriots by magic means such as the myths and legends of Borneo and masks in children’s imagination.It is also noteworthy that the novel talks about the relationship between individual freedom and national identity in depth,and describes the tragic fate of cross-national love in the period of national opposition.These nation-state discourses in Boar Crossing the River are Zhang Guixing’s biggest transitions when missing in the literary world for 17 years,which indicate a landmark progress in his spiritual history.

Horizontal freezing study for cross passage of river-crossing tunnel

To determine the appropriate soft foundation treatment for a river-crossing tunnel, freezing reinforcement design and technology were introduced based on the channel tunnel design and construction practice. Through finite element analysis and engineering practices, two rows of horizontal perforated freezing pipes were designed and installed on both sides of a passage for tunnel rein- forcement, which produced the thickness and strength of frozen crust that satisfied the design requirements. These information are valuable for guiding the design and construction of river-crossing tunnels in coastal areas.

Habitat fragmentation and the population status of rodents in Abayum forest, Ikom, Cross River State, Nigeria

The threat to wildlife population is attributed to various anthropogenic activities. The main objective of this study was to identify the influence of fragment size on the population density of rodents in the study area. Fourteen (14) out of forty (40) fragments existing in the area were randomly sampled. The parameters used for the study were number, size of fragments and the corresponding population distribution of rodents in the study area. Fifty hunters in the area were also interviewed. The fragments were stratified into first, second and third order fragments on the basis of their sizes and randomly selected for the study. Indirect method of wildlife census was carried out through the observation of droppings, trail or tract, burrows, eating habits and noise. Fragment growth rate was 18 to 40 (87.5%) in 7 years. Anthropogenic perturbations in the form of cultivation of permanent cropland, settlement expansion, bush burning, timber exploitation and new settlements in areas previously thinly settled or not accessible to outsiders have resulted in disjointed ecosystems. The population density of rodents correlated with fragment size was highly significant ((P < 0.05) r = 0.9). It was then concluded that fragment size greatly influenced the population and diversity of rodent species. It was recommended that the remaining large fragments in the study area should be protected by law from further fragmentation.

Physico-chemical indices of breeding sites of Simulium damnosum in the lower Cross River Basin, Nigeria

To determine the factor influencing the abundance development and distribution of Simulium damnosum(S.I) immature stages in the lower Cross River Basin, Nigeria, the physico-chemical characteristics of water at breeding sites were analysed longitudinally over a 12 month period. Analysis of the water samples showed that water current correlated positively and significantly(p<0.05), with dissolved oxygen(r = 0.95 vs 0.10); conductivity(r = 0.95 vs 0.81); hydrogen ion concentration(r = 0.03 vs 0.46); and biochemical oxygen demand(r = 0.80 vs 0.64); from Agbokim Waterfalls and Afi River respectively. The result indicates that these parameters and low ionic concentration are the most essential requirement for the development of S. damnosum pre-imaginal stages. Amplitudes of annual variability as measured by co-efficient of variation varied between the parameters. From the trends in hydrological variables it was deduced that the integrated impact of precipitation, input of surface runoff and municipal effluents played an overriding role in determining the absolute levels and temporal pattern in the water quality attributes. Of the 3578 pre-imaginal stages of S. damnosum collected, 52.52% and 47.4% were collected from Agbokim Waterfall and Afi River respectively. There was a significant difference(p<0.05) in the number of pre-imaginal stages collected from both sites. The highest number of pre_imaginal stages of S. damnosum collected were at the peak of rain(July—September) indicating that S. damnosum in the River Basin is a wet season breeder. The need for long term laboratory colonization of blackfly immature stages becomes imperative especially how these parameters could be exploited in control programme through the testing of larvicides without adverse ecological damage to the aquatic habitat.

Ecosystems Services of the Tropical Rain Forest Environment: Lessons from the Cross River National Park, Nigeria

This paper essayed to examine ecosystem functions with a case study of the tropical rainforest environment of the Cross River National Park, Nigeria. The paper highlighted the important functions of the ecosystems to include Purification of air and water mitigation of floods and droughts, detoxification and decomposition of wastes, generation and renewal of soil and natural vegetation, pollination of crops and natural vegetation, control of the vast majority of potential agricultural pests, dispersal of seeds and translocation of nutrients, maintenance of biodiversity, protection from the sun’s harmful ultraviolet rays among others. Problems associated with the rainforest ecosystems among which are logging, traditional methods of farming, poaching, excessive noise and encroachment were identified. The paper concluded by highlighting the way forward among others that, awareness creation should be stepped-up in Support Zone Communities;indigenes should be educated periodically on the benefits of the ecosystem services to not just humans but the forest resources and biodiversity themselves.

Evaluation of the Anti-Poaching Programme of the Cross River National Park Okwango Division, Nigeria 2002 to 2013

Poaching of wildlife has continued to be the major problem confronting national parks managers in Nigeria in spite of effort being made to curb the ugly trend. This paper examined the anti-poaching programme of the Cross River National Park Okwango Division Nigeria from 2002 to 2013, with a view to making recommendations for the improvement of the programme. Focused group discussions, personal interviews, review of official records and structured questionnaires were used to collect data. Analysis of variance using randomized complete block design and student’s t-test were used to analyse data. Result showed that 1 - 5 arrests of poachers per month per patrol station was significantly (P 0.05) in the number of poachers arrested and fined between 2002 to 2006 and 2007 to 2011. The low performance of the anti-poaching programme was attributed to poorly equipped rangers’ posts as well as well the absence of alternative livelihood options in the enclave and surrounding communities. It was recommended that more rangers should be employed, and the rangers should be adequately kitted, well equipped patrol stations be constructed and the enclave and surrounding communities be involved in the management of the National Park in addition to providing them with alternative livelihood options.

Survey of Medicinal Plants Used in the Treatment of “Ailments of Utmost Native Importance” in Cross River State, Nigeria

Regardless of the high value of medicinal plants to residents of Cross River State in health maintenance especially for the treatment of “ailments of utmost native importance”, the major constraint is the uncertainty of the availability of the herbs and knowledge of traditional medicine still being passed by word of mouth. For better reliance on the plant species as medicine, this research seeks to identify and infer on the population and distribution of the species used in their treatment and documents them. Data were collected using field work and oral interviews. The survey team comprised of Taxonomists, survey assistants, five trado-medical herbal practitioners and the Authors. The status and geographical distribution of the identified medicinal plant species was appalling, 59 percent of the medicinal plant species were distributed in 3 out of 15 sampled plots. Causal factors included over misuse of therapeutic plant species, habitats destruction and absence of proper conservation education of the masses. Recommendations are that Communities should set up therapeutic plants farms, enrichment planting be made in agricultural fields and sustainable harvesting methods used.

Re-examination of Hydrochemistry and Groundwater Potentials of Cross River and Imo-Kwa-Ibo Intersecting Tropical Basins of South-South Nigeria

This review attempted a detailed description of geological and hydrogeological configurations of Cross River and Imo-Akwa Ibo basins.It presented a synthesis of hydrochemistry and a description of the hydrogeological configurations of the two basins.Hydrogeologically,most areas under Cross River and Imo-Kwa-Ibo are poor in terms of groundwater potentials.Based on the hydrochemistry,the basins hold water of excellent quality.Groundwater sources fall in soft to moderately hard classes.The entire sources groundwater has a TDS concentration of less than 500 mg/l.Groundwater classification based on electrical conductivity(EC)showed EC levels were less than 500μS/cm.Most of the examined cations and anions are within WHO reference guidelines for drinking water quality.However,no broad analysis of water quality based on water quality indices.Also,studies modeling pollution or the impact of land use changes on groundwater quality are wanting.Thus,further analysis of the hydrochemistry of groundwater aquifers is recommended.

Species Composition and Gear Characteristics of the Macrobrachium Fishery of the Cross River Estuary,Nigeria

The Cross River Estuary,Nigeria,is an important shrimping area for artisanal fishermen of the coastal communities.The multi-species Macrobrachium fishery is exploited with three main gears,namely beach seine,push net and trap.Studies on species composition of this fishery recorded thirteen shrimp species,one swimming crab (Callinectes amnicola) and two fish species (Eleotris sp.and Pellonula leonensis).The shrimp species identified included Macrobrachium macrobrachion (83.39% and 55.69% by number and weight,respectively),M.vollenhovenii (9.66% and 37.18%),M.equidens (3.8% and 2.87%),juveniles-sub-adults of Penaeus notialis (1.11% and 1.3%),M.dux,M.felicinum,Palaemonetes africanus,Palaemon maculatus,Palaemon elegans,Desmocaris sp.,Leander sp.,Nematopalaemon hastatus and Alpheus pontederiae.While the selectivity index for trap was 0.25,beach seine and push net had a lower index of 0.063.The results present the first comprehensive and representative report for the Estuary shrimp fishery and will assist in the management of the biodiversity of this ecosystem.

水下穿越管道外腐蚀检测评价系统River-ROV的应用性研究

长输油气管道的江河水下穿越管道由于施工和和环境等问题使得管道面临严峻的腐蚀损伤风险,由于缺乏对应的技术手段,绝大多数穿越管段未能开展相关的检测。在全国长输油气管道大力度提升管道安全管理的背景下,迫切地需要先进的检测手段,本文采用江河水下River-ROV检测技术进行应用性研究和试验,选取两处大开挖穿越管段的管道为代表,验证了其技术的适用性和可靠性,实现水下穿越管道的外腐蚀状况检测和评价,为水下穿越管道的维护维修项目提供全面准确有效的数据支持,运营安全管理形成操作性强的技术支持。

长江流域环境案件跨区域集中管辖问题研究

以行政区划为标准的传统环境司法管辖模式与长江流域环境保护的生态性、整体性、系统性相矛盾,而流域环境案件集中管辖可作为破解环境治理难题的关键路径。通过实证分析可以发现,目前长江流域所涉各省跨行政区划集中管辖的具体实践存在行政区划分离程度不高、法律规范依据不足、环境司法专门机构设置衔接不畅等制约因素。因此,要明确以流域治理所遵循的整体和系统理论为基础,确立长江流域地理单元为基础的整体环境治理理念,确保集中管辖实质效用得到发挥;确立与完善流域跨行政区划环境案件管辖法律规范供给,为司法实践提供统一标准遵循;坚持环境司法专门化改革,以长江生态环境法院为基础框架发展完善专门管辖,以便破除行政区划对流域环境司法的阻碍,增强流域集中管辖的规范性、有效性。

问诊天堑:基于多源数据的城市跨江城区数字体检与优化策略研究——以南京浦口中心城区为例

城市体检是识别诊断“城市病”的有效途径,数字技术为城市体检提供了方法基础,针对不同的区域对象需提出特色的诊断指标。本文以城市跨江城区为研究对象,跨江发展是滨江城市突破拓张城市规模的重要措施,由于江河的自然地理条件限制,跨江城区易出现空间发展不协调、服务设施不匹配、城市活力不足等问综合问题,需要通过数字化体检评估加以应对。在南京浦口中心城区的实例研究中,基于多源大数据从交通便捷、风貌特色、城区活力等维度进行数字体检,发现其交通组织“潮汐交通”、风貌特色“屏风遮廊”、生活圈“跨域割裂”等问题,并从空间形态、设施布局、景观风貌等方面提出针对性的优化策略。

长江三角洲白山羊不同杂交组合早期生长发育性状研究

为了研究长江三角洲白山羊不同杂交组合生长发育的差异,以长江三角洲白山羊为母本、以萨能奶山羊和波尔山羊为父本进行杂交选育,分析萨白F_(1)、波萨白F_(2)和长江三角洲白山羊F_(0)60日龄体重与体尺指标的变化。结果显示:波萨白F_(2)各日龄体重、平均日增重均显著高于长江三角洲白山羊F_(0)(P<0.05);波萨白F_(2)各日龄体重和平均日增重均高于萨白F_(1),萨白F_(1)各日龄体重和平均日增重均高于长江三角洲白山羊F_(0),但差异均不显著(P>0.05)。整个试验期间,波萨白F_(2)、萨白F_(1)各日龄体尺指标均高于长江三角洲白山羊F_(0),但差异均不显著(P>0.05);各组羊的体尺数据随着日龄的增加呈递增的趋势。该试验通过分析不同杂交组合羔羊体重、体尺等早期生长发育性状,为培育具有较高经济价值的长江三角洲白山羊肉用品种(系)提供了一定参考。

中哈跨界河流合作:进程、机遇与深化路径

中哈跨界河流合作机制以联合委员会为平台,在水文信息交换、水质保护、水量分配、水利工程合作等方面取得突出成果,中哈两国政治关系的提升、环委会的积极配合及“一带一路”倡议相关政策的支持是推进中哈跨界河流合作的主要因素;同时,中哈跨界河流合作机制也面临一系列挑战;制定切实有效的水资源分配规则,深化跨界河流环保合作,重视跨界含水层条约的签订,构建系统的跨界水合作制度以及多元化的水争端解决方法体系,并提升国际话语权引导国际舆论等是应对挑战,实现中哈跨界水资源可持续利用的关键。

跨河桥梁河道段整治工程设计方案研究

公路或者铁路等交通线路跨越河道交叉工程规划的是否合理,关系到工程的投资以及协调、施工和管理的难易程度,也关系到工程能否顺利推进。在公路桥桥墩难以避开河道条件下,根据堤线布置原则,结合河道水流条件和协调难度等因素,坚持少征地或不征地,在保证河道行洪能力前提下,对不同河道堤线和断面型式进行了比选,提出最优设计方案,为类似工程提供借鉴。

长三角一体化发展:演变历程、现状分析与对策建议

作为推进中国式现代化的重要引擎,长三角一体化主要经历了初步探索、合作深化、持续拓展、高质量发展四个发展阶段,并实现了治理模式从分割式治理到一体化协同式治理的转型,主要体现在区域治理组织、区域治理内容、区域治理形态三个方面。近年来,长三角一体化建设不断取得实质性发展,区域协同治理绩效日益显现,但仍存在“行政区行政”产生区域分割和地方主义、一体化的体制机制障碍、一体化的领域发展不够均衡等现实问题。为推进长三角一体化发展,应围绕建构跨域治理模式、优化区域一体化体制机制、有序推进各领域一体化建设等方面综合施策。