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The notable improvement of China's wetland management policies over the last four decades prompted this study's goal to quantitatively analyze the transformation of China's coastal wetland policies from 1979 to 2022 by applying an institutional network analysis and policy text analysis. The results of the institutional network analysis revealed an administrative management transformation from a multidepartmental mode to an integrated management framework. Furthermore, the policy text analysis results revealed a change in policy priorities (from exploitation to protection) and management targets (from a single environmental element to a comprehensive ecosystem and further to collaborative governance). In addition, the overall outcome of this study instigated proposals for the improvement of future wetland policies on climate change, integrated planning, natural capital, and public participation. Hence, this study presents an example of wetland policy analysis based on a quantitative review, which we hope will also be valuable for other countries.

Modeling coastal land use/cover (LULC) change is one of the most accurate methods for understanding temporal change in the coastal system. In this study, we first time combined Land Change Modeler, Habitat Quality Model, and Digital Shoreline Analysis System to quantify temporal coastal LULC change and driving forces between 2000-2020; combined CA-Markov Model with Sea Level Affecting Marshes Model (SLAMM) and merged the local study area’s SLR data with future representative concentration pathway (RCP8.5) scenarios to predict future coastal LULC change and associated sea-level rise (SLR) impact on the coastal land use and habitat quality in short-, medium- and long-term. Between 2000-2020, the study area experienced considerable coastal LULC change, including tidal flats, whose change was driven mainly by sea level with a total net gain of 57.93 km2, and mixed forest with a net gain of 25.90 km2. We also observed the significant loss of developed land whose change was influenced by mixed-forest and tidal flat with a total loss of -75.58 km2. From 2020 to 2060, the tidal flat will observe a remarkable net gain of 80.55 km2; these gains will make developed land the most impacted land in the study area. The study concluded that, the conversion of tidal flat, mixed-forest and mangroves into agricultural and infrastructural areas were main drivers influenced the change. The other responsible of the changes were the 450 m of coastal erosion and 400 m of accretion observed over 20 years. The study concluded that, low coastal elevation of -1m and flat slope of less than 2 degrees have also contributed to coastal change. These unprecedented changes will inevitably threaten the coastal ecosystem services, socio-economic development, and food security. Therefore, timely actions should be taken by enabling sustainable mitigation and development programs to prevent the future impacts.

Non-point source pollution (NSP) and runoff intensities and distribution are primarily affected by landscape structure and composition. Multiple causalities hinder our ability to determine significant variables that influence NSP. Therefore, we developed an approach that integrates the Soil and Water Assessment Tool (SWAT), random forest regression model, redundancy analysis, and correlation coefficient to assess the role of landscape structure on runoff and NSP in the Dongsheng basin. We used R to calculate landscape metrics and the SWAT to simulate NSP loads from 1990 to 2019. redundancy analysis (RDA), random forest, and Pearson correlation were used to analyze the relationships among landscape metrics and NSP variables. The largest patch index (LPI) shows a significant negative correlation with NSP, with an R2 of −0.58 for TP and TN and −0.62 for sediment load. The findings indicate that landscapes with larger patch sizes, a high number of patches, and aggregation of patches largely influence pollution distribution. Overall, the results suggest that the role of landscape patterns on NSP outweighs that of runoff. Moreover, the findings infer that the aggregation and connectivity of forest patches contribute to the decline in NSP load and vice versa for cropland cover. Thus, for sustainable watershed management, it is crucial to encourage unfragmented landscapes, especially pollutant-intercepting landcovers such as forests.

This paper seeks to analyse the present and future land-use change transition intensity (using Pontius intensity model) and landscape pattern using landscape metrics to investigate the relationship between the land cover regions, landscape pattern and the changes in the size of Bojiang lake in Ordos basin from 1987-2017. The accelerated changes in each land use region from 1987 and 2017 subsequently led to changes in landscape pattern. The changes experienced within 1987 and 2017 including the future changes indicated that the grassland and sparsely vegetated region increased significantly, dominating the study region which however indicated an increase in anthropogenic activities like agricultural activities in the study region. Based on our observation in this study, the change in each land use region although showed a significant relationship with the change in water region including Bojiang lake, other external factors also contributed to the changes in the size of the lake.

Rainwater harvesting (RWH) has emerged as one of the efficient strategies to augment surface and groundwater sources to meet water resource demands. The aim of this study is to present a methodology for siting RWH areas and selecting appropriate RWH structures in a watershed using Geographic Information Systems (GIS) and Remote Sensing (RS) based multi-criteria analysis. Derived thematic layers such as drainage density, slope, road network, runoff potential, distance to streams, and distance to built-up areas were used to identify suitable areas for RWH. The Weighted Linear Combination (WLC) technique was used in combination with the Boolean approach in a GIS environment. Normalized weights assigned to thematic layers and features were tested for consistency using the consistency ratio in Analytical Hierarchy Process. The study area can be divided into three categories of suitability, i.e.: (i) Most suitable with 26% coverage (167 km2); (ii) moderately suitable with 30% coverage; and (iii) least suitable with 12.6% coverage (80 km2) of the study area. Suitable RWH and artificial recharge structures were identified based on identified zones. It was found that 11 check dams could be implemented in the study area and 3 percolation tanks along streams and on the ground. This cost-effective and low data-intensive methodology presented can be replicated by relevant stakeholders in arid regions to adopt RWH as an effective strategy to address growing water shortages.

The application of Species Distribution Models (SDM) in the management of species habitat and environmental impact changes has been widely used by scientists and ecologists globally, however this study proposes a novel analytical technique involving the combination of a statistical ranking algorithm and Remote sensing GIS data (habitat and threat) to analyze the suitability hierarchy of the habitat of a signature water-bird (Larus relictus). The results indicate that about 47.63% of the study region was suitable to accommodate L. Relictus during their breeding/resting season, while 27.08% proved to be highly unsuitable for this species. Based on the spatial distribution of the statistical data already incorporated into the GIS environment, it was observed that regions surrounding the Bojiang Lake (especially polygons 38 and 42) dominated by low vegetation and increased amount of moisture proved to be the best region for this species. On the contrary, polygon 23, located in the southern part of the study region proved to be the worst region for this species being dominated by significantly high amount of threat factors having the highest mean normalized hierarchical value and ranking 60th out of 61 in terms of standard deviation. To distinctively capture different suitability level of the study region, we could say that the application of this technique is quite effective and beneficial. This is because, compared to other decision making tools, this technique which solely relies on remote sensing and vector data gives decision makers an option of weight application if so desired.

Atmospheric environmental issues have evolved from point source pollution to regional pollution, leading to controlling specific air pollutant emissions. A-value method has been found suitable for estimating large-scale atmospheric environmental capacity rather than small-scale, resulting in the inaccuracy of developing air pollution control strategy. This study proposed a grid computing method based on the CALPUFF modelling system and GIS spatial analysis tool. The meteorological data from the MM5 model were used to simulate the spatial distribution of air pollutants. The meteorological flow field data was used to simulate the ventilation coefficient. The A value was revised with the simulated to achieve accurate results of atmospheric environment capacity. The credibility was verified by applying this method to Fengtai District, Beijing, China. The research area was divided into small partitions via the ArcGIS spatial analysis tool. The simulation results agreed well with the observation data from actual monitoring stations, even for the PM10 concentration with the most significant error (MRE: 7.05%−13.28%, RMSE: 11.62–17.89, R2: 0.84–0.90). The GIS spatial analysis tools were applied to match the underlying surface types and overcome the restrictions of administrative boundary management. The study proposed four schemes to achieve differentiated air pollutant emission reduction and develop suitable control strategies. Furthermore, this method can be applied on different scales of natural geographic boundaries and realize the precise spatial management of atmospheric environmental capacity.

A proper understanding of watershed spatio-temporal hydrological characteristics is critical to the management of a watershed and its natural resources such as water and vegetation. Rainfall runoff estimation plays an important role as an integral part of watershed management. Runoff volume and distribution data provides valuable information for water management strategies such as selection of artificial water abstraction sites, water storage facilities, and soil erosion control strategies. In the present study Bojiang lake watershed was used to indicate the application of Soil Conservation Service Curve Number method (SCS-CN) coupled with Geographic Information System (GIS) and Remote Sensing (RS) techniques. The watershed falls within Erdos Larus Relictus National Nature Reserve (ELRNNR) which was listed under the wetlands of international importance in 2002. Rainfall runoff is influenced by a variety of factors within a watershed such as soil and land use/cover types, soil moisture content, rainfall, drainage density, and shape and size of the watershed. The SCS Curve number is the most popular and widely applied method for runoff estimation. GIS and Remote Sensing play an important role in estimating surface runoff by SCS-CN method. ArcGIS 10.2 software was used to overlay different thematic layers and develop an attribute table and calculate a weighted curve number. The weighted curve number was applied to the SCS-CN equations to estimate daily, monthly, and yearly runoff. Correlation coefficient (r) was used to test for the relationship between rainfall and runoff, and verify the computation of the method. The results show an average runoff of 17.78 mm which is about 7.18% of the annual average rainfall for the years 2001-2016. The derived output maps can assist in identifying suitable areas for water recharge/abstraction. The study demonstrates that SCS-CN in conjunction with GIS and RS can be used to calculate runoff for ungagged watersheds and assist in watershed management strategies.

Studying the persistence and spatial-temporal trends of air pollution is beneficial for determining the pollutant risk area and enables the development of associated prediction tools and models. Relying on the PM2.5 concentrations data retrieved via remote sensing from 2000 to 2018, the spatial and temporal pattern, variation tends, and persistence is determined through the Theil-Sen median trend analysis, Mann-Kendall, and Hurst exponent. We combine the Theil-Sen Median + Mann-Kendall and Hurst to quantitatively and qualitatively predict the future trends of China's PM2.5 concentrations as a new perspective. Results reveal that PM2.5 concentrations increased at first and then decreased significantly, with 2009–2011 as the turning point for PM2.5 pollution changes, particularly in Central China and the Southeast Coastal Area. The area where PM2.5 concentrations were below 10 μg/m3 account for 29.75% of China's total territory, reaching the annual average criterion value determined by the World Health Organization. The areas presenting a continuous increase (15.69%) and decline (17.46%) of PM2.5 concentrations were almost equal. As a result, the constant monitoring of the variance in PM2.5 concentrations in the sustainably increased and underdetermined regions, such as Tibet and Northeast China, is needed. This study used simulated PM2.5 concentrations data as a valuable complement to China's ground monitoring stations, thus compensating for a shortage of long-term series data. Grid data analysis can more finely show the interior disputes in PM2.5 concentrations. The algorithm codes can be freely downloaded and become a helpful tool for analyzing the spatio-temporal variation characteristics of primary air pollutants.

Przewalski’s gazelle (Procapra przewalskii) is one of the most endangered species listed in the IUCN Red List. It is endemic to China and a flagship species in the eastern part of the Qinghai-Tibetan Plateau. Here, we assembled the complete mitochondrial genome (mitogenome) of P. przewalskii for the first time. Moreover, we conducted the phylogenetic analysis including other 11 species of subfamily Antilopinae and two species of subfamily Caprinaeas as outgroups. The complete mitogenome of P. przewalskii was 17,376 bp in length, and contained 13 protein-coding genes (PCG), two ribosomal RNA genes (12S rRNA and 16S rRNA), 22 transfer RNA (tRNA) genes and a non-coding control region (D-loop). Among the tRNA genes, both the tRNASer and tRNALeu had a replication. The base content of the mitogenome was that A, C, G and T occupied 33.9, 24.5, 13.3 and 28.3%, respectively. The GC content was 37.8% accordingly. The molecular phylogenetic analysis showed that Przewalski’s gazelle had a close relationship with Mongolian gazelle (P. gutturosa).

This study involves the initiation of a novel data driven habitat suitability hierarchical approach used for the identification and prediction of suitable regions for Larus relictus a signature waterbird specie of Erdos Larus relictus National Nature Reserve (ELRNNR). This approach was proposed using GIS to incorporate a readily available environmental parameters (NDVI, NDWI, Slope, DEM, Land use, NDBI) used as the Remote sensing (RS) information and the threat factors (road networks, developed buildings and vegetation) used as the vector information to allow us quantitatively describe the habitat suitability for L. relictus. The RS and Vector information were statistically analyzed and ranked before incorporation into thiessen polygon using ArcGIS to produce the final habitat suitability output which was validated using a conventional habitat suitability model (weight applied). A sensitivity analysis conducted to assess the contribution of each parameter to this approach revealed that threat factors (Vector dataset) was the most significant factor. It was also revealed that this approach compared with HSM showed some statistical relationships indicating similar predictions in most region specifically the high and the low suitable regions. From the results, about 8% of the study region was predicted to be highly suitable for this species most of which was situated around the Lake in the region. The southern and northwestern regions covering about 45% of the study region proved to be unsuitable due to the significantly high density of threat factors in those regions. Compared to other decision making models, this approach possesses some unique qualities like flexibility and autonomy giving its users the options of weight application and reliance on expert opinion when necessary. It is also anticipated towards supporting conservationist and resource managers with the development of strategies or recommendations for sustainably managing the ecosystem to enhance the protection of L. relictus or other waterbird species in the region.

In recent years, with the significant increase in urban development, it has become necessary to optimize the current air monitoring stations to reflect the quality of air in the environment. Highlighting the spatial representation of some air monitoring stations using Beijing's regional air monitoring station data from 2012 to 2014, the monthly mean particulate matter concentration (PM10) in the region was calculated and through the IDW interpolation method and spatial grid statistical method using GIS, the spatial distribution of PM10 concentration in the whole region was deduced. The spatial distribution variation of districts in Beijing using the gridding model was performed, and through the 3-year spatial analysis, PM10 concentration data including the variation and spatial overlay (1.5 km × 1.5 km cell resolution grid), the spatial distribution result obtained showed that the total PM10 concentration frequency variation exceeded the standard. It is very important to optimize the layout of the existing air monitoring stations by combining the concentration distribution of air pollutants with the spatial region using GIS.

This study briefly discussed water hygiene condition in Rural Bekwarra Community. Based on the 5 selected parameters for the experiments, results showed that average permeate Fluoride was 1.6 mg/L, pH of 7.8, average Iron (Fe+3) of 0.7 mg/L, Lead (Pb) of 0.02 mg/L, and Total Dissolved Solids of 578 mg/L. From the results, it showed that only pH had average value within the standard requirement for drinkable water in Nigeria. Thus, there is a considerable need for the treatment and recycling of borehole water in the community before use.

Anaerobic digestion of sewage concentrates represents a very suitable means of generating bioenergy while reducing a huge amount of waste to disposal. Effective biogas production from sewage sludge can be achieved by optimizing operational conditions. In this study, the research was designed to compare the biogas production efficiency from sewage sludge recovered from coagulation and absorption process with sludge recovered from bioflocculation, centrifuged and chemical coagulation (Al2(SO4)3+CMC) processes through biomethane potential experiment (BMP). From the results obtained, the maximum methane production rate of 56.85 mLCH4/gCOD was achieved from concentrates collected during coagulation and absorption treatment process without solid retention time (SRT), concentrates collected during 0.5 d SRT had maximum methane production rate of 110.88 mLCH4/gCOD, methane production rate of 154.28 mLCH4/gCOD was achieved from 2 d SRT concentrate. The Al2(SO4)3+CMC treated concentrate had methane yield of 143 mLCH4/gCOD while bioflocculation concentrate had methane yield of 139 mL/gCOD and centrifuged concentrate had the yield of 124 mL/gCOD within the period of 22 to 29 days. The overall result showed that concentrates recovered from coagulation, adsorption and Al2(SO4)3+CMC processes produced the highest methane with better efficiency and recorded the most stable performance throughout the period of the experiment and this encouraged the future use in anaerobic digestion for large scale methane production.

This review presents the recent state of Dynamic membrane (DM) technology as the alternative for Ultrafiltration, Microfiltration and membrane bioreactor (MBR) system. DM technology involves the application of physical materials such as mesh or clothes as a barrier that enhances the formation of a cake layer on their surfaces. This technology has been used extensively in local filtration processes. DM has a lower risk of membrane fouling, lower capital cost and requires little energy compared to MBR. The performance of DM was evaluated to obtain a suitable method for membrane filtration technology. Further suggestion to encourage the application of this technology in wastewater treatment plant was given.

Anaerobic digestion of sewage concentrates represents a very suitable means of generating bioenergy while reducing a huge amount of waste to disposal. Effective biogas production from sewage sludge can be achieved by optimizing operational conditions. In this study, the research was designed to compare the biogas production efficiency from sewage sludge recovered from coagulation and absorption process with sludge recovered from bioflocculation, centrifuged and chemical coagulation (Al2(SO4)3+CMC) processes through biomethane potential experiment (BMP). From the results obtained, the maximum methane production rate of 56.85 mLCH4/gCOD was achieved from concentrates collected during coagulation and absorption treatment process without solid retention time (SRT), concentrates collected during 0.5 d SRT had maximum methane production rate of 110.88 mLCH4/gCOD, methane production rate of 154.28 mLCH4/gCOD was achieved from 2 d SRT concentrate. The Al2(SO4)3+CMC treated concentrate had methane yield of 143 mLCH4/gCOD while bioflocculation concentrate had methane yield of 139 mL/gCOD and centrifuged concentrate had the yield of 124 mL/gCOD within the period of 22 to 29 days. The overall result showed that concentrates recovered from coagulation, adsorption and Al2(SO4)3+CMC processes produced the highest methane with better efficiency and recorded the most stable performance throughout the period of the experiment and this encouraged the future use in anaerobic digestion for large scale methane production.

In this study, the clinoptilolite is taken as the matrix, manganese nitrate as a modifier; through a medium temperature calcination pore making technique. Mostly, the micro pores in the matrix have been enlarged through the means of dipping and high temperature calcination modification. A small amount of active catalytic components are exchanged stably between the pores and surface. The mechanism of manufacturing new catalyst is analyzed using test methods of TEM, SEM, EDS, XRD and BET. These test methods testify the existence of active catalytic components of manganese in the Mn-Zeolite, while researching a new type of Mn-zeolite catalyst heterogeneous catalytic mechanism of Fenton and ozone oxidation process. The results show that added Mn-zeolite could improve the oxidation rate from 51% to 100%. Addition of free radical inhibitor, t-butanol, significantly inhibited the catalytic reaction of Fenton and ozone oxidation. This indicated that the mechanism of the reaction of Fenton and ozonation followed the hydroxyl radical.

In this study, the research protocol was designed to examine the effect of hydraulic retention time (HRT) on the efficiency of the production of biogas from sewage concentrates recovered from coagulation and adsorption process from Xiao Jiahe municipal wastewater treatment plant and to report on its overall performance. Three complete-mix, continuous stirred tank reactor (CSTR) with working volume of 900 mL were used. The digesters were operated at different HRT of 10 d, 20 d and 30 d. Biogas produced had methane composition of 60-70% and biogas production rates of 18 mL/d in reactor 1, 169 mL/d in reactor 2 and 114 mL/d in reactor 3. Reactor 3 showed stable performance with the highest methane yield of 166 mL/gCOD. Reactor 1 recorded lowest methane yield of 10 mL/ gCOD. Due to high organic loading rate (OLR) and shorter HRT, the VS degradation and biogas yield in reactor 1 decreased. Based on the data from this study, 30 d HRT and OLR of 0.6 gCOD/(L.d) was suggested as the designed criteria for ideal methane production from CSTR anaerobic digestion AD of sewage sludge recovered from coagulation and adsorption process.