Erosion Rates in Dam Catchments in Jordan—Effects of Topography, Geology, and Urbanizations

Erosion as a natural process produces soils, which are very important natural resources for the fest land plant- and animal kingdoms. Loss of the soil cover reduces agricultural production, biodiversity, and the role of soil as a filter for infiltrating water to replenish the groundwater. It also threatens the food supplies. The knowledge of erosion rates of rocks and terrains is important for developing proactive measures to protect soils from erosion and loss. In this study, erosion rates of catchment areas were calculated based on dams’ catchment extensions and the sediment loads transported by flood flows into dams’ lakes. The study results show that the chemically, via floodwater, transported quantities of materials are negligible compared to the solid materials transported by the water. It calculates erosion rates ranging from 0.013 to 0.212 mm/yr (13 - 212 m/106 yr) for the different catchment areas. Erosion rates in Jordan are, generally, higher than those calculated for the different parts of the world ranging from 2.5 to 60 m/106 yr. This fact can be explained by the very steep topography, calcareous rock cover of the catchment areas and the barren rock exposures.

Use of biopolymers in wastewater treatment:A brief review of current trends and prospects

Indeed,polymeric materials have thrived in worldwide sectors over the last five decades due to their versatility and durability,to the point that we can no longer envisage a product that does not contain them.However,many synthetic polymers that have been produced are mostly sourced from petroleum and coal as raw materials,making them environmentally incompatible because they cannot be integrated with what is a natural recycling system.One of the most important aspects of the transition to a circular bioeconomy(CBE)is the provision of more sustainable strategies for resource and waste management.Considering the environmental consequences associated with petroleum-based polymers(PBPs),natural biopolymers,originating from biomass,can be conceived as a promising solution to gradually replace the PBPs,and address,and resolve the potential challenges and prevailing research gaps in the PBPs.The biopolymers have significant advantages over PBPs in terms of low-cost/zero-cost precursors,environmental friendliness,and user-friendliness.The present review dissects the sources,synthesis pathways,structures,characterization,and employment of biopolymers and their composites in water and wastew-ater treatment applications via different scenarios.Furthermore,the CBE model framework proposes potential approaches to applying CBE principles in the wastewater management sector,with a heavy emphasis on not only technology but also organizational and societal reforms.To sum up,the reliance on biopolymers can be considered a crucial tool for assessing the global progress toward CBE,as well as future environmental management and planning.

Developing allometric equations to estimate forest biomass for tree species categories based on phylogenetic relationships

The development of allometric biomass models is important process in biomass estimation because the reliability of forest biomass and carbon estimations largely depends on the accuracy and precision of such models.National Forest Inventories(NFI)are detailed assessments of forest resources at national and regional levels that provide valuable data for forest biomass estimation.However,the lack of biomass allometric equations for each tree species in the NFI currently hampers the estimation of national-scale forest biomass.The main objective of this study was to develop allometric biomass regression equations for each tree species in the NFI of China based on limited biomass observations.These equations optimally grouped NFI and biomass observation species according to their phylogenetic relationships.Significant phylogenetic signals demonstrated phylogenetic conservation of the crown-to-stem biomass ratio.Based on phylogenetic relationships,we grouped and matched NFI and biomass observation species into 22 categories.Allometric biomass regression models were developed for each of these 22 species categories,and the models performed successfully(R^(2)=0.97,root mean square error(RMSE)=12.9​t·ha^(–1),relative RMSE=11.5%).Furthermore,we found that phylogeny-based models performed more effectively than wood density-based models.The results suggest that grouping species based on their phylogenetic relationships is a reliable approach for the development and selection of accurate allometric equations.

Specific Heat Capacity of A2FeCoO6-δ (A = Ca or Sr)

A2FeCoO6-δ (A = Ca or Sr) is synthesized by the solid-state synthesis method and their specific heat capacities are evaluated at 40˚C using a heat flow meter. The effect of the A-cation size on the specific heat capacity of these compounds is observed. The specific heat capacity of Sr2FeCoO6-δ is found to be the highest, and that of Ca2FeCoO6-δ is the lowest while CaSrFeCoO6-δ shows the intermediate value. The specific heat capacity decreases with the decrease of the average A-site ionic radius, demonstrating the relationship between heat capacity and A-site ionic radius. The relationship between specific heat capacity and molar mass is also confirmed as the δ value decreases or molar mass increases from Ca2FeCoO6-δ to CaSrFeCoO6-δ to Sr2FeCoO6-δ.

Assessing the Impact of Fugitive Dust Emissions from Cement Silos at Cluster of Concrete Batching Facilities Using Air Dispersion Modeling

This research assessed the environmental impact of cement silos emission on the existing concrete batching facilities in M35-Mussafah, Abu Dhabi, United Arab Emirates. These assessments were conducted using an air quality dispersion model (AERMOD) to predict the ambient concentration of Portland Cement particulate matter less than 10 microns (PM10) emitted to the atmosphere during loading and unloading activities from 176 silos located in 25 concrete batching facilities. AERMOD was applied to simulate and describe the dispersion of PM10 released from the cement silos into the air. Simulations were carried out for PM10 emissions on controlled and uncontrolled cement silos scenarios. Results showed an incremental negative impact on air quality and public health from uncontrolled silos emissions and estimated that the uncontrolled PM10 emission sources contribute to air pollution by 528958.32 kg/Year. The modeling comparison between the controlled and uncontrolled silos shows that the highest annual average concentration from controlled cement silos is 0.065 μg/m3, and the highest daily emission value is 0.6 μg/m3;both values are negligible and will not lead to significant air quality impact in the entire study domain. However, the uncontrolled cement silos’ highest annual average concentration value is 328.08 μg/m3. The highest daily emission average value was 1250.09 μg/m3;this might cause a significant air pollution quality impact and health effects on the public and workers. The short-term and long-term average PM10 pollutant concentrations at these receptors predicted by the air dispersion model are discussed for both scenarios and compared with local and international air quality standards and guidelines.

Plant functional trait diversity and structural diversity co-underpin ecosystem multifunctionality in subtropical forests

Tree species diversity is assumed to be an important component in managing forest ecosystems because of effects on multiple functions or ecosystem multifunctionality.However,the importance of tree diversity in determining multifunctionality in structurally complex subtropical forests relative to other regulators(e.g.,soil microbial diversity,stand structure,and environmental conditions)remains uncertain.In this study,effects of aboveground(species richness and functional and structural diversity)and belowground(bacterial and fungal diversity)biodiversity,functional composition(community-weighted means of species traits),stand structure(diameter at breast height and stand density),and soil factors(pH and bulk density)on multifunctionality(including biomass production,carbon stock,and nutrient cycling)were examined along a tree diversity gradient in subtropical forests.The community-weighted mean of tree maximum height was the best predictor of ecosystem multifunctionality.Functional diversity explained a higher proportion of the variation in multifunctionality than that of species richness and fungal diversity.Stand structure-played an important role in modulating the effects of tree diversity on multifunctionality.The work highlights that species composition and maximizing forest structural complexity are effective strategies to increase forest multifunctionality while also conserving biodiversity in the management of multifunctional forests under global environmental changes.

Comparison Study on Sedimentomorphological Characteristics Using Integrated Geo-Techniques: A Case Study of Two Representative Areas in Kuwait

Intensive aeolian processes occur due to the scarcity of rainfall and lack of vegetation cover in arid regions. The study of recent surface sediments in arid areas is important for environmental assessments, evaluation of natural resources, and land use planning. In this study, two areas were chosen as they show changes in lithology, environment and landforms. The two study areas are Al-Rawdatain in the northern part, and Al-Managish in the southern part of Kuwait. The current study aims to define the sedimentomorphic zones in these areas, with an emphasis on Quaternary geomorphological evolution by providing an integrated approach based on satellite images, topographic maps, field measurements, and laboratory analysis. Remote sensing data were spatially analyzed to classify and detect the temporal changes in the surface sediments and geomorphology based on the field measurements (n = 42) as ground truthing points for supervising the classification. Samples from both areas were collected and subjected to grain size (dry mechanical sieving) and X-Ray Diffraction (XRD) analysis. The resulting data were statistically analyzed for grain size distributions and mineralogy based on the US standard set of sieves. The study found that the Aeolian sand sheet deposits are the most frequent recent surface deposits in Kuwait and cover most of the other sediments. The direction of movement of the sand sheets is from NW towards SE. The mineralogical composition of the aeolian recent surface sediments revealed that they are mostly derived from the Dibdibba Formation and Tigris-Euphrates fluvial terrace deposits. Quartz is the most frequent component of the studied surface sediments in the study areas (66%). The calcite mineral is also found in subordinate amounts in the study areas (10%).

Comparative Analysis of PM10 Emission Rates from Controlled and Uncontrolled Cement Silos in Concrete Batching Facilities

This research study quantifies the PM10 emission rates (g/s) from cement silos in 25 concrete batching facilities for both controlled and uncontrolled scenarios by applying the USEPA AP-42 guidelines step-by-step approach. The study focuses on evaluating the potential environmental impact of cement dust fugitive emissions from 176 cement silos located in 25 concrete batching facilities in the M35 Mussafah industrial area of Abu Dhabi, UAE. Emission factors are crucial for quantifying the PM10 emission rates (g/s) that support developing source-specific emission estimates for areawide inventories to identify major sources of pollution that provide screening sources for compliance monitoring and air dispersion modeling. This requires data to be collected involves information on production, raw material usage, energy consumption, and process-related details, this was obtained using various methods, including field visits, surveys, and interviews with facility representatives to calculate emission rates accurately. Statistical analysis was conducted on cement consumption and emission rates for controlled and uncontrolled sources of the targeted facilities. The data shows that the average cement consumption among the facilities is approximately 88,160 (MT/yr), with a wide range of variation depending on the facility size and production rate. The emission rates from controlled sources have an average of 4.752E-04 (g/s), while the rates from uncontrolled sources average 0.6716 (g/s). The analysis shows a significant statistical relationship (p < 0.05) and perfect positive correlation (r = 1) between cement consumption and emission rates, indicating that as cement consumption increases, emission rates tend to increase as well. Furthermore, comparing the emission rates from controlled and uncontrolled scenarios. The data showed a significant difference between the two scenarios, highlighting the effectiveness of control measures in reducing PM10 emissions. The study’s findings provide insights into the impact of cement silo emissions on air quality and the importance of implementing control measures in concrete batching facilities. The comparative analysis contributes to understanding emission sources and supports the development of pollution control strategies in the Ready-Mix industry.

三江源和祁连山国家公园雪豹种群的遗传结构分析

掌握遗传信息对濒危物种的保护和管理具有重要意义。本研究在我国雪豹重要分布区祁连山和三江源国家公园分别采集粪便样品,利用mtDNA的cyt b基因、微卫星多态性位点进行了雪豹的物种鉴定、个体识别和种群遗传结构评估。在采集286份疑似雪豹粪便样品中,成功的对86份雪豹样品进行了扩增鉴定,利用微卫星位点进行个体识别获得41只雪豹个体,其中祁连山国家公园26只,三江源国家公园15只。通过等位基因数、有效等位基因数、观测杂合度、期望杂合度、多态信息含量等指标进行种群遗传多样性评估,认为雪豹种群遗传多样性相对较低,但祁连山国家公园雪豹种群遗传多样性相对较高。STRUCTURE进行群体遗传结构分析表明,4个种群可以划分为3个遗传类群,祁连山国家公园的种群(YCW和QLS)与三江源国家公园种群(DC和SJ)的遗传差异,可能与种群间的地理隔离存在明显的相似性。

北京市夏季低层大气NO_x、O_3垂直分布观测研究

根据 2 0 0 0年夏季在北京 32 5 m铁塔上的一次梯度观测实验 ,给出 8m,12 0 m和 2 80 m三层上的 NO、NO2 、O3 浓度的观测结果。对 NO,NO2 ,O3 小时平均浓度的日变化和垂直分布规律进行了分析 ,结果发现 :(1)各高度上的 NO,NO2 ,O3 浓度均有明显的日变化特征 ,阴雨天的日变化更加复杂 ;(2 ) O3 在晴朗白天有单、双及三峰型分布 ;(3)相对于 12 0 m和 2 80 m,近地面 8m处的 NO浓度最高 ,而 O3 浓度最低 ;(4) NO2 、O3 日平均浓度日变化振幅 12 0 m处最大 ;(5 )中午前后 NO,NO2 ,O3 浓度均在 12 0 m最高。

砷对水稻根部渗氧分布和铁膜形成的影响（英文）

研究砷对三种水稻品种(玉香油占、CNT87059和南洋占)生物量、根部渗氧径向分布、根表铁膜形成以及砷在植物体内积累的影响。在土壤中分别添加50和100 mg/kg砷、并以未经处理的含砷8.5 mg/kg的土壤作为对照,结果表明,随着砷处理浓度的增加,水稻根表铁膜的含量增加;水稻根尖渗氧率与根基部渗氧率的比值随着砷处理浓度的增加而降低,水稻根部渗氧模式从"紧密型"向"疏松型"转变;与对照样品相比,50和100 mg/kg砷处理能显著增加水稻根部的砷积累(P<0.05);低渗氧能力水稻品种(南洋占)谷粒砷含量显著高于高渗氧能力水稻品种(CNT87059,P<0.05)的谷粒砷含量。

利用N_2-Ar-He示踪法研究粤东嵩溪大型银锑矿成矿流体

嵩溪银锑矿是90年代初发现的一个大型新型独立银矿,其成因存在海底基性火山喷流和浅成中低温火山热液充填两种不同观点。前者认为成矿流体为海底热卤水,而后者则认为主要来自岩浆水,但有大气降水加入。较系统的N_2-Ar-He组成和He同位素研究清楚地显示嵩溪成矿流体主要来源于建造水或称沉积热卤水,其中幔源岩浆水的比例很小,一般<5％。从成矿流体来源看,嵩溪银锑矿成因类型应属沉积热卤水改造型。

淋溶条件下赤泥盐分离子的迁移与分布（英文）

赤泥是氧化铝工业生产过程产生的强碱性固体废物,其盐分含量高,对环境有害且制约着赤泥堆场的植被重建。通过土柱模拟淋溶实验,研究赤泥盐离子的动态迁移及垂直分布情况。结果表明:淋溶不同程度地将赤泥中的Na^+、K^+、Ca^(2+)、CO_3^(2-)、SO_4^(2-)和HCO_3^-等盐分离子浸出到渗滤液中,显著降低了赤泥的盐度。赤泥中Na^+和K^+呈现出较高的迁移能力,从柱体的40~50 cm处向上迁移至20~30 cm处;而Ca^(2+) 的迁移能力较弱,主要分布在柱体的30~40 cm处。淋溶刚结束时,CO_3^(2-)主要分布在柱体的20~30 cm处,随后向下迁移至30~40 cm处,最终受蒸发作用迁移至20~30 cm处。SO_4^(2-) 最初主要分布在柱体的40~50 cm处,最终向上迁移至20~30 cm处。HCO_3^-主要停留在柱体的下部,其迁移特性受蒸发的影响较小。

森林与径流关系——一致性和复杂性

@论文综述国外近一个世纪以来在配对集水区研究方面所取得的结论,从水的自然属性出发,从森林变化对径流(年径流量、洪峰与枯水径流)的影响,径流响应的干扰临界值及水文恢复各方面探讨森林变化与径流关系的一致性与复杂性。森林变化与径流关系的一致性主要表现在由较长时间尺度表达的年径流量上。绝大多数的配对集水区的试验研究表明,采伐森林就会增加年径流量,而在荒地上造林就会减少年径流量。而由较短时间尺度表达的洪峰径流与枯水流量则呈现较大的复杂性和难预估性。综述表明,对径流特别是洪峰与枯水径流的定义及分析方法的不同也是造成森林与径流关系复杂性的重要原因。森林与径流关系的复杂性要求人们在研究及应用其关系时就必须有系统观,必须考虑植被、径流与其它过程(土壤变化、气候变化等)的相互作用。论文还认为尽管配对集水区试验作为一种研究方法为研究者提供了许多可靠的结论,但由于许多研究者只把集水区看作是“黑箱”Q从而对认识森林与径流关系的复杂性有一定的局限性。未来的研究应把配对集水区的试验与其它对过程的研究技术(同位素、GIS等技术)结合起来。

赤泥碱性阴离子浸出优化及溶解行为（英文）

赤泥是氧化铝工业生产过程中产生的高碱性固体废弃物。基于单因素-正交实验开展赤泥碱性阴离子浸出特性研究,结合多级浸出实验探讨最佳浸出条件、碱性阴离子分布特征、关键碱性离子类型及其溶解行为。结果表明:在液固比2 mL/g、浸出温度30°C、浸出时间23 h、2次浸出条件下,可溶性碱性阴离子(CO^(2-)_3,HCO^-_4,Al(OH)^-_4,OH^-)的最佳浸出率达86%;赤泥1次浸出液中,88%的阴离子来源于可溶性碱(NaOH、碳酸盐、碳酸氢盐、NaAl(OH)_4),12%的阴离子来源于化学结合碱(方解石、钙霞石、水化石榴石);在最佳浸出条件下,可溶性碱性离子浸出总浓度为69.78 mmol/L,CO^(2-)_3约占75%;碳酸盐溶解反应的表观活化能为10.24k J/mol,这主要受固膜扩散控制。

甘草内生细菌对4种植物病原菌的抑菌谱及其16SrRNA系统发育分析

旨在筛选对4种植物病原真菌具有拮抗活性的甘草内生细菌,为新疆甘草内生细菌的开发应用提供理论依据。采用平板对峙培养法从100株甘草内生细菌中筛选对石榴枯萎病甘薯长喙壳、草果叶斑病镰刀菌、草果假茎黑斑病小孢拟盘多毛孢、墨兰炭疽病胶孢炭疽菌等4个病原菌具有拮抗活性的菌株,并测定其16SrRNA基因序列,建立系统发育树对其进行初步鉴定。结果显示,61株菌株对甘薯长喙壳具有拮抗作用,其中13株菌的抑菌半径均大于15mm。进一步研究表明,10株菌对4种植物病原菌都表现出较高的抑菌能力。基于16Sr RNA基因序列分析与系统发育分析表明,其中11株菌为萎缩芽孢杆菌(Bacillus atrophaeus),另外2株菌分别为副氧化微杆菌(Microbacterium paraoxydans)和莫哈韦芽胞杆菌(B.mojavensis)。

Yield and Nicotine Content of Flue-Cured Tobacco as Affected by Soil Nitrogen Mineralization

Nitrogen(N)supply is the most important factor affecting yield and quality of flue-cured tobacco(FCT).A field experiment and an in situ incubation method were used to study the effects of soil N mineralization in the later stages of growth on yield and nicotine content of FCT in Fenggang and Jinsha,Guizhou Province.The yield and market value of FCT at Fenggang were much lower than those at Jinsha.However,the nicotine content of middle and upper leaves was much higher at Fenggang than at Jinsha when the same rate of fertilizer N was applied,which might be due to a higher N supply capacity at the Fenggang site.At later stages of growth(7-16 weeks after transplanting),the soil net N mineralization at Fenggang(56 kg N ha^(-1))was almost double that at Jinsha(30 kg N ha^(-1)).While soil NH_4-N and NO_3-N were almost exhausted by the plants or leached 5 weeks after transplanting,the N taken up at the later growth stages at Fenggang were mainly derived from soil N mineralization,which contributed to a high nicotine content in the upper leaves.The order of soil N contribution to N buildup in different leaves was:upper leaves>middle leaves>lower leaves.Thus,soil N mineralization at late growth stages was an important factor affecting N accumulation and therefore the nicotine content in the upper leaves.

工业废弃物对赤泥碱性调控的应用研究进展（英文）

赤泥是氧化铝工业生产过程中产生的强碱性废弃物,其碱性是制约赤泥资源化处置的主要影响因子。赤泥脱碱研究工作已开展数十年,但因技术经济性差始终未能实践应用。采用工业废弃物调控赤泥碱性既可大量减少废物的处置费用,也可产生良好的生态环境效益。论文在综述赤泥碱性来源以及工业废弃物处置方式的基础上,提出了"以废治废"的研究思路,探讨了赤泥碱性调控的瓶颈问题,阐述了典型工业废弃物(废气、废水和废渣)对赤泥碱性的转化机制,指出了应用工业废弃物改良赤泥碱性研究的重点发展方向,这将为赤泥的土壤化处置和堆场的生态修复实践提供科学基础。

Effect of Long-Term Fertilization on Organic Nitrogen Forms in a Calcareous Alluvial Soil on the North China Plain

In order to illustrate the change of nitrogen (N) supply capacity after long-term application of manure and chemical fertilizer, as well as to properly manage soil fertility through fertilizer application under the soil-climatic conditions of the North China Plain, organic N forms were quantified in the topsoil with different manure and chemical fertilizer treatments in a 15-year fertilizer experiment in a Chinese calcareous alluvial soil. Soil total N (TN) and various organic N forms were significantly influenced by long-term application of chemical fertilizer and manure. TN, total hydrolysable N, acid-insoluble N, amino acid N and ammonium N in the soil increased significantly (P < 0.05) with increasing manure and fertilizer N rates, but were not influenced by increasing P rates. Also, application of manure or N fertilizer or P fertilizer did not significantly influence either the quantity of amino sugar N or its proportion of TN. Application of manure significantly increased (P < 0.05) hydrolysable unknown N, but adding N or P did not. In addition, application of manure or N fertilizer or P fertilizer did not significantly influence the proportions of different soil organic N forms.