Restoration or Rehabilitation of the Faleme River Affected by Mining Activities: What Methods?

The Faleme River, a West Africa long transboundary stream (625 km) and abundant flow (>1100 million m3) is affected by severe erosion because of mining activities that takes place throughout the riverbed. To preserve this important watercourse and ensure the sustainability of its services, selecting and implementing appropriates restorations techniques is vital. In this context, the purpose of this paper was to present an overview of the actions and techniques that can be implemented for the restoration/rehabilitation of the Faleme. The methodological approach includes field investigation, water sampling, literature review with cases studies and SWOT analysis of the four methods presented: river dredging, constructed wetlands, floating treatment wetlands and chemical precipitation (coagulation and flocculation). The study confirmed the pollution of the river by suspended solids (TSS > 1100 mg/L) and heavy metals such as iron, zinc, aluminium, and arsenic. For the restoration methods, it was illustrated through description of their mode of operation and through some case studies presented, that all the four methods have proven their effectiveness in treating rivers but have differences in their costs, their sustainability (detrimental to living organisms or causing a second pollution) and social acceptance. They also have weaknesses and issues that must be addressed to ensure success of rehabilitation. For the case of the Faleme river, after analysis, floating treatment wetlands are highly recommended for their low cost, good removal efficiency if the vulnerability of the raft and buoyancy to strong waves and flow is under control.

An integrated north–south paleo-Dadu-Anning River: New insights from bulk major and trace element analyses of the Xigeda Formation

The Xianshuihe-Anninghe fault extends SE–S and constitutes the southeastern margin of the Tibetan Plateau.However,the Dadu River which is associated with the fault does not flow following the path,but makes a 90ºturn within a distance of 1 km at Shimian,heading east,and joins the Yangtze River,finally flowing into the East China Sea.Adjacent to the abrupt turn,a low and wide pass near the Daqiao reservoir at Mianning separates the N–S course of the Dadu River from the headwater of the Anning River which then flows south into the Yunnan Province along the Anninghe fault.Therefore,many previous studies assumed southward flow of the paleo-Dadu River from the Shimian to the Anning River.However,evidences for the capture of the integrated N–S paleo-Dadu-Anning River,its timing,and causes are still insufficient.This study explored the paleo-drainage pattern of the Dadu and Anning Rivers based on bulk mineral and geochemical analyses of the large quantities of fluvial/lacustrine sediments along the trunk of the Dadu and Anning Rivers.Similar with sands in the modern Dadu River,the Xigeda sediments also exhibit a granitoid affinity with the bulk major mineral compositions of quartz(>50%),anorthite(about 10%),orthoclase(about 5%),muscovite(about 5%),and clinochlore(about 4%).Correspondingly,bulk major elements show high SiO_(2),with all samples>60%,and some of them>70%,low TiO_(2)(≤0.75%),P_(2)O_(5)(≤0.55%),FeO*(≤5%),and relatively high CaO(1.02%–8.51%),Na_(2)O(1.60%–2.52%),and K_(2)O(2.17%–2.71%),with a uniform REE patterns.Therefore,synthesizing all these results indicate that these lacustrine sediments have similar material sources,which are mainly derived from its course in the Songpan-Ganzi flysch block,implying that the paleo-Dadu originally flowed southward into the Anning River and provided materials to the Xigeda ancient lake.The rearrangement of the paleo-Dadu River appears to be closely related to the locally focused uplift driven by strong activities of the XianshuiheXiaojiang fault system.

Morphological comparison and molecular marker screening of three Skeletonema species found in Changjiang(Yangtze)River Basin

In our recent investigations of diatom diversity,we studied three species,namely,Skeletonema costatum,Skeletonema subsalsum,and Skeletonema potamos.Although they have been found frequently in Changjiang(Yangtze)River Basin,their morphological and molecular identification is difficult in taxonomy.Therefore,to integrate morphological and molecular biological approaches,we compared systematically their morphological characters and performed phylogenetic analysis.Twelve strains of Skeletonema were collected and isolated from Shanghai and Jiangsu,China,and their morphological characteristics were examined by light microscopy(LM)and the scanning electron microscopy(SEM).Based on morphological comparison,we determined that S.potamos is easy to distinguish from the other two species.The heavily silicified areolae,undulated or cleft distal ends of terminal fultoportula processes(TFPPs),absence of basal pores of fultoportula processes(FPPs),the rootlike protrusions of FPPs,and no interlocking connection are the stable characteristics that can be used to identify S.potamos.However,there are only two features that can distinguish S.costatum from S.subsalsum,namely the location of terminal rimoportulae(TRPs)and the distal shape of TFPPs.In addition,we amplified and sequenced nine common genetic markers from the strains,from which 101 sequences were obtained,constructed phylogenetic trees based on the nine genes and evaluated that seven genes can be used to identify S.potamos,and revealed that S.subsalsum is the closest known relative of S.costatum,and only ATP synthetase beta-subunit gene(atp B)is able to distinguish them from each other,which strongly support that it is an effective molecular marker for Skeletonema.This work provided a theoretical basis for the taxonomic study of Skeletonema.

Examining the evolution of tidal creeks in the Huanghe River delta using multi-temporal Landsat images

Coastal tidal creeks are important channels for exchanges of material and energy between sea and land,and play an important role in the ecological protection of tidal flats.Although tidal creeks have evolved differently in various regions,the evolutionary process of tidal creeks in the Huanghe(Yellow)River delta of China,one of the most active deltas worldwide,is not entirely clear.Therefore,the evolution of tidal creeks in the delta from 1981 to 2021 was investigated by quantitatively analysing the tidal creeks and developing a standard for dividing their evolution periods.Visual interpretation and supervised classification methods were applied to the Landsat images to extract the tidal creek network,and 17 groups of tidal creek systems were selected.Results indicate that Creek S 1 was the most developed creek for having 113 tidal creeks totaling 65.8 km in length,while Creek E 3 had the fastest growth rate for having average annual increase of 1.9 km.Meanwhile,the level of tidal creeks increased,the average and median lengths of tidal creeks increased,and the number of tidal creeks decreased since 1981.The evolution of the tidal creek system could be divided into four stages,namely,rising,developing,stabilizing,and degrading.Analyses of a representative tidal creek show that there was no degenerated tidal creek during the rising period,with an increase in the number of 50 and a length increase of 57.9 km between 1981 and 1989.The proportion of new tidal creeks in the developing period was more than 50%and the new tidal creeks in the stabilizing period were equal to the degraded tidal creeks.Extinct tidal creeks were greater than 50%during the degrading period.There was no fixed order of tidal creek evolution in each period,and there may be a skip in evolution.Our findings provided a reference for studying the evolution of tidal creeks.

Coordinated Mining Procedures of Open Pit Mines Based on River Management

This paper primarily concerns the effective coordination of the procedures and methods employed in open pit mining operations under the background of river management.The central objective of this study is to identify a viable approach for ensuring rational and efficient development of open pit mineral resources while simultaneously protecting and restoring the ecological environment of the river.This approach should facilitate the realization of a harmonious symbiosis between mining and river management.The intricate mutual influence relationship between river management and open pit mining is first analyzed in depth,which provides a solid foundation for the subsequent coordination strategy development.In light of the aforementioned considerations,a set of coordination procedures for open pit mining based on river management conditions is proposed.These procedures emphasize the integration of river protection into the overall layout of mining at the planning stage.The implementation of scientific mining schemes,accompanied by rigorous control of the scope and depth of mining operations,has proven to be an effective means of reducing the impact of mining activities on river environments.This approach has also facilitated the achievement of a balance and coordination between mining and river management.

Function Evolution and Landscape Planning Strategy of Inland Rivers in Beilun Port City of Ningbo

In the history, the main roles of inland rivers in Beilun Port City of Ningbo were desalination,blocking tides, shipping, and flood control. Nowadays, with the continuous spread and deepening ofurbanization, the ecological environment of river courses has been destroyed. In the past, remediationmeasures based on engineering and technology played a certain role, but can not “cure the root cause”. Itshould respect the historical evolution process of river courses, and highlight the ecological service functionand leisure tourism value of river courses from the coordination perspective of urban and rural ecologicalenvironment, economic industries, society and culture in the planning ideas of ecology, production, andlife integration. Four aspects of the measures are as below: protecting and repairing the ecological matrixof river courses;building green space system and maintaining flood control functions through the waternetwork;protecting cultural heritage along the rivers;developing waterfront leisure tourism scenic area.

Ganges and Brahmaputra River System: Need for a Multi-Country Plan for Cleaning, Mitigation, Restoration and Protection

The Ganges and Brahmaputra River system is in the plains of the northern Indian subcontinent. The river is a wide sluggish stream flowing through densely populated and fertile agricultural regions of the world. The Ganges is known as the Hinduism holy river. In Bangladesh, the Brahmaputra is joined by the Teesta River. The western branch of the Brahmaputra confluences with the Ganges and contains most of the river flow. The eastern branch joins the Meghna River near Dhaka. The basin covers parts of four countries including India, Nepal, China, and Bangladesh. Of greater concern, however, has been the degradation in quality of the river water itself. The primary objective of this research is to encourage the development of a multi-country clean-up, mitigation, and protection plan for the Ganges-Brahmaputra rivers. This article constitutes a real tool for the restoration, enhancement and protection of the Ganges-Brahmaputra River system and its environment. The Ganges and Brahmaputra rivers are known for stream bank erosion, shifting channels, and sandbars that continually emerge in their course. The Ganges and Brahmaputra watershed is home to hundreds of millions of people, with the result that the river’s water over much of its course is highly polluted. Arsenic contamination of groundwater in Bangladesh continues to be the largest case of human poisoning in history. Catastrophic floods have prompted the World Bank to prepare a long-term flood-control plan for the region. Scores of cities and towns contribute to treated sewage into the river and its main tributaries, and dozens of manufacturing facilities contribute industrial waste. Also contributing to high pollution levels are agricultural runoff, the remnants of partially burned or unburned bodies from funeral pyres, and animal carcasses. High levels of disease-causing bacteria, as well as such toxic substances as chromium, cadmium, and arsenic, have been found in the Ganges and Brahmaputra. External research and funding of adsorptive media systems to help mitigate the high arsenic levels in drinking water (river and groundwater) is needed. The Ganges-Brahmaputra River system is of colossal importance to its entire environment. Restoration and protection measures must be adopted appropriately and at the scale of the concerned countries.

Response of ecosystem carbon storage to land use change from 1985 to 2050 in the Ningxia Section of Yellow River Basin,China

Regional sustainable development necessitates a holistic understanding of spatiotemporal variations in ecosystem carbon storage(ECS),particularly in ecologically sensitive areas with arid and semi-arid climate.In this study,we calculated the ECS in the Ningxia Section of Yellow River Basin,China from 1985 to 2020 using the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model based on land use data.We further predicted the spatial distribution of ECS in 2050 under four land use scenarios:natural development scenario(NDS),ecological protection scenario(EPS),cultivated land protection scenario(CPS),and urban development scenario(UDS)using the patch-generating land use simulation(PLUS)model,and quantified the influences of natural and human factors on the spatial differentiation of ECS using the geographical detector(Geodetector).Results showed that the total ECS of the study area initially increased from 1985 until reaching a peak at 402.36×10^(6) t in 2010,followed by a decreasing trend to 2050.The spatial distribution of ECS was characterized by high values in the eastern and southern parts of the study area,and low values in the western and northern parts.Between 1985 and 2020,land use changes occurred mainly through the expansion of cultivated land,woodland,and construction land at the expense of unused land.The total ECS in 2050 under different land use scenarios(ranked as EPS>CPS>NDS>UDS)would be lower than that in 2020.Nighttime light was the largest contributor to the spatial differentiation of ECS,with soil type and annual mean temperature being the major natural driving factors.Findings of this study could provide guidance on the ecological construction and high-quality development in arid and semi-arid areas.

Research on Kunming Urban Riverbank Greening Construction

Urban riverbank has connected water and land eco-system in the city,not only playing a vital role in releasing flood and conserving water and soil,but also of significant landscape and ecological value.In view of riverbank greening construction in the comprehensive improvement of rivers in Kunming City in recent years,the paper has analyzed three common riverbank greening modes based on the field survey,that is,protective greening,landscape greening and ecological greening.Then,some suggestions and countermeasures have been proposed,including enhancing construction of ecological river,exploring historical and cultural connotation of rivers,and selecting reasonable plants' species and disposition mode.

Waterfront Landscape Planning along the Yihe River in the New District of Luoyang City in China

General situation of the Yihe River in the new district of Luoyang City and its evolution history were introduced and evaluated from 4 perspectives of water,embankment,vegetation and traffic accessibility.On this basis,orientation of waterfront landscape planning of the Yihe River in the overall urban planning of Luoyang City was proposed,and it was proposed that waterfront landscape planning in the study area should follow the principles of "ecological,cultural and regional,public,accessible and human-centered".It was to provide references for the landscape planning and design of the Yihe River in the new district of Luoyang City,and to promote its waterfront landscape construction.

Ecological Restoration and Landscape Construction of Wetland——A Case Study of Planning and Design of Mi River Wetland Park in Linqu of Shandong

Based on geological characteristic of Mi River Wetland Park in Linqu of Shandong,the paper had illustrated historical and cultural spirits of Linqu,and then proposed planning strategies and contents of Mi River Wetland Park.It discussed new approaches for wetland restoration and landscape construction from the perspectives of ecological restoration of wetland system,overall construction of leisure system,and full display of regional characteristic.The construction of wetland system laid stress on water system design,terrain treatment,vegetation construction,and biological diversity creation.Wetland system would be overlaid with leisure system,divided into wetland leisure zone,wetland entertainment zone,humanity landscape zone,wetland science popular zone and wetland experience zone,all of which would be constructed with characteristic respectively.On the basis of site character,the paper had searched an energy balance and substance transformation method between rivers,plants,earth and humans,of certain practicality.

On the Regional Ecological Planning of the Ancient Yellow River Course in Shangqiu City

This paper analyzed the problems of eco-environment along the ancient Yellow River course and, by combining with the planning scheme of ecological projects of the ancient Yellow River course in Shangqiu City, discussed its ecological planning ways in terms of the principles, objectives, methods and contents of the ecological planning and design to promote the regional eco-environment construction of the ancient Yellow River course.

Prediction of Maize Yield and Its Component Factors in Yellow River Irrigation Area of Ningxia under Climate Change

[Objective] The aim was to quantitatively predict the variation trend of maize yield in Yellow River irrigation area of Ningxia under future climate change scenarios.[Method] Based on the data of daily temperature,precipitation and radiation in 25 km × 25 km grid in Ningxia from 2010 to 2100 obtained by regional climate model,maize yield in Yellow River irrigation area of Ningxia in the 21st century was studied by means of corrected CERES-Maize model.[Result] With climate warming,maize yield in Yellow River irrigation area of Ningxia in 2020s and 2050s showed increase trend compared with base years（average in 1961-1990）when current adaptive maize variety and optimum production management measures were adopted,while maize yield went down in 2080s with the further increase of temperature.The grain number per spike and spike grain weight as the yield components of maize also showed the same trend with maize yield.In 2020s and 2050s,the increase of maize yield under B2 scenario was higher than that under A2 scenario,while the decrease of maize yield under B2 scenario was lower than that under A2 scenario in 2080s.[Conclusion] With the increase of temperature,maize yield in Yellow River irrigation area of Ningxia went up firstly and then went down.

The Greening Situation and Developing Countermeasures along the Han River——Taking Chaozhou Downtown Part as an Example

Hanjiang is the main river in Chaozhou. The urban sections on both sides of it are large-scale landscape zones which combine the natural landscape and the cultural landscape. Aiming at better manifesting the geographical features and pro-moting the sustainable development of the ecological environment on both sides of the Hanjiang River, the research, with the reach between the Jinshan River and the Hanjiang River as an example, pointed out the existing problems and put forward some constructive suggestions based on a thorough survey on the plant species and the rationality of plant configuration and the afforstation managements, in order to provide reference for the decision-maker of the further planning and construction of this area.

Creation of "Regional Characteristic" in Planning and Design of Farmers' Residential Area at the South of Lower Reaches of the Yangtze River

After analysis of location feature of the south of lower reaches of Yangtze River and its construction of urban and rural integration,the paper pointed out harmonious combination between natural and artificial factors had been neglected in planning and design of farmers' residential area at the south of lower reaches of Yangtze River,"regional characteristic" losing,residential area in the form of "city community" and buildings in European style.In view of these problems,relevant planning and design thoughts and methods had been proposed as to how to create "regional characteristic" from the perspective of planning,architecture and landscape design.It discussed with emphasis the importance of construction base type and combination of environment with residential area construction;inspirations and design methods obtained from traditional architectures;and the content of landscape overall planning and specific design.It was hoped to enlighten designers to shoulder social and historical responsibility,make exploration unremittingly,and construct beautiful homelands for people.

Moving Dynamics of Nitrate Nitrogen in Soil of Maize Field on Meadow Soil of Daling River Valley in Liaoning and Its Fertilization Controlling

The moving dynamics of nitrate nitrogen（NO3-N）in soil of maize field on meadow soil of Daling river valley in Liaoning and its rational fertilization controlling were discussed in this study by the designing of different kinds of N application methods.The results showed that the content of NO3-N in soil was increased with the amount of nitrogen fertilizer;At the same amount of nitrogen fertilizer,the content of NO3-N in soil showed a trend of chemical fertilizerstraw treatmentslow controlled release fertilizer.Based on the requirement of roots in different growth stages to nutrition,the migration directions of NO3-N could be regulated by each layer of soil.In the early growth stage,the NO3-N would move upward,while it moved downward in the late growth stage.Straw returning treatment could improve the keeping ability of soil to NO3-N and avoid the downward migration of NO3-N,as well as reduce the damage of groundwater pollution.The use of slow controlled release fertilizer had achieved the continuing releasing of nutrition.Moreover,the peak of nutrition releasing had been delayed for 30 d,which had met the requirement of nutrient supply in maturing stage.The yield of slow controlled release fertilizer treatment was the highest with the least accumulation of NO3-N and less negative influence on environment.The yield of straw returning treatment and chemical fertilizer treatment was closed to each other.

Strategic Planning of "Yellow River Golden Bank" of Yinchuan Section

Through the analysis on location condition,industrial development situation of "Yellow River Golden Bank" of Yinchuan section,strategic idea for this section has been proposed,providing theoretical basis for Yinchuan City to build a distinctive city along Yellow River.

Quantitative Allocation Analysis of "Raising by Planting" System Combining Fruits and Poultry for Mountainous Region in Headwaters of Dongjiang River

[Objective] The aim was to promote nutrient cycling and utilization in the mountain＇s system combining fruits and poultry and to control non-point source pollution produced from swine raising and navel orange planting in headwaters of Dongjiang River. [Method] The quantitative analysis was mainly conducted for the so called ＂raising by planting＂ which is about material cycle in ＂pig-methane-fruit-fish＂ model and energy cascade utilization, based on relationship between excreted amount by livestock and the utilized quantity in Xinlin Farm in Longtang Town, Dingnan County, Jiangxi Province. [Result] Considering N requirement by fruit trees, a navel orange orchard （1 mu） could support about 2.72 pigs, the equipped biogas pool （1.88 m3） could support 1 166.67 kg of duckweeds and a fish pond could support 25.57 grass carps. In contrast, a satsuma orchard （1 mu） could support about 1.96 pigs, the equipped biogas pool （1.35 m3） could support 841.53 kg duckweeds and the fish pond could support 18.44 grass carps. [Conclusion] The results provided scientific references for quantitative allocation of members in ＂pig-methane-fruit-fish＂ model when popularized in headwaters of Dongjiang River.

Distribution and partitioning of heavy metals in large anthropogenically impacted river, the Pearl River, China

In order to evaluate the distribution and partitioning characteristics of heavy metals in the large anthropogenically impacted Pearl River Basin, the contents of ‘‘anthropophile'' elements(Cr, Ni, Cu, Zn, Cd and Pb,which are clearly influenced by human activities) were determined, and their partitioning coefficients(Kd) between water and sediments and enrichment factors(EF) were calculated for samples collected at different locations along the Pearl River main stream. The modified BCR sequential extraction procedure(proposed by the European Community Bureau of Reference in 1993), which involves the successive extraction of metals in a decreasing order of reactivity, was applied. Sediment samples from the upper,middle, and lower reaches were included in this study. The results showed that the content of most metals in water and sediment samples gradually increases from upstream to downstream, suggesting a possible input from human activities as shown by their increasing high EF, ranged from 1.4 to 3.9 for Cu, from 1.4 to 6.7 for Zn, from 2.5 to59.1 for Cd, and from 1.7 to 8.9 for Pb, respectively. Thehigher partition coefficients(Kd) for Cr, Zn, and Pb(10~5–10~6) indicated that they were mainly transported in solid phase, while parts of Ni, Cu, and Cd were transported in dissolved phase as they display relatively lower Kdin the range of 10~4–10~5. According to the results of the BCR leaching, the percentage of non-residual fraction of heavy metals in the sediments showed a decreasing order of Cd [ Pb [ Zn [ Cu [ Ni [ Cr, implying that Cd and Pb were more active and bioavailable compared to the other four metals, and thus would be potentially more harmful to the watershed ecosystem.

Why Was the Strengthening of Rainfall in Summer over the Yangtze River Valley in 2016 Less Pronounced than that in 1998 under Similar Preceding El Nino Events？Role of Midlatitude Circulation in August

It is widely recognized that rainfall over the Yangtze River valley （YRV） strengthens considerably during the decaying summer of E1 Nifio, as demonstrated by the catastrophic flooding suffered in the summer of 1998. Nevertheless, the rainfall over the YRV in the summer of 2016 was much weaker than that in 1998, despite the intensity of the 2016 E1 Nifio having been as strong as that in 1998. A thorough comparison of the YRV summer rainfall anomaly between 2016 and 1998 suggests that the difference was caused by the sub-seasonal variation in the YRV rainfall anomaly between these two years, principally in August. The precipitation anomaly was negative in August 2016--different to the positive anomaly of 1998.