Heavy Vegetation Research Articles

Risk Assessment of Heavy Metal Accumulation in Leafy Vegetables Around Wastewater-irrigated Areas

The consumption of heavy metal-contaminated vegetables poses a threat to human health and the environment. This study assessed the level of heavy metals in selected leafy vegetables collected from wastewater-irrigated agricultural land located at Jalkuri Union of Siddhirganj Upazila in Narayanganj district of Bangladesh. The mean concentrations of metals were decreasing in the following order: Fe > Mn > Zn > Pb> Cr> Cu > Ni > Cd in wastewater, Fe> Mn > Cr > Zn > Ni > Pb> Cu> Cd in irrigated soil, and Fe > Zn > Mn> Cu> Pb > Cr> Ni > Cd in leafy vegetables. The contamination factor (CF) showed that the soils were moderate to highly contaminated by Cr and Cd. The pollution load index (PLI) and geo-accumulation index (Igeo) values of the analyzed samples revealed that the soils were non-polluted to moderately polluted. The target hazard quotients (THQ) for most of the metals were <1, suggesting non-carcinogenic health hazards for humans. The target carcinogenic risk (TCR) of heavy metals, except for Pb, was above the safe standard, suggesting a carcinogenic risk (CR) for their consumption. It is a matter of concern that regular intake of contaminated leafy vegetables in the area would increase health risk, as the hazard index (HI) was greater than 1. The study observed that vegetables should not be irrigated with contaminated water, and industrial wastewater must be properly treated before discharging into the environment.

Potentially toxic metals in Northeast Ethiopian agricultural soils: implications for Solanum lycopersicum (Tomato) production and human health.

Exposure to heavy metal-contaminated vegetables, irrigation water and agricultural soil is one of the most challenging environmental issues worldwide. This study aimed to evaluate the health effects of potentially toxic metals (PTMs) including Cr, Cd, Fe, Pb, Cu, Zn, and Co from agricultural soil, irrigation water, and tomato plants collected from the Abuarie irrigation site, Northeast Ethiopia. The samples were digested using acid digestion method, and its concentration was quantified using Inductively Coupled Plasma-Optical Emission Spectroscopy. The concentrations of PTMs in the soil, tomato, and irrigation water samples ranged from 49,020 ± 275 (Fe) to 11.85 ± 0.44 (Cd), 170 ± 1.98 (Fe) to 0.29 ± 0.006 (Cd) mgkg-1, and 0.24 ± 0.003 (Fe) to 0.025 ± 0.005(Ni)mgL-1 , respectively. The results revealed Zn, Ni, Cd and Cr in soil, all metals in tomato, and Cu, Ni, Cd and Pb in irrigation water sample were above the World Health Organization threshold values. Moreover, the separate and cumulative exposure to farm soil, irrigation water, and consumption of tomato were investigated using the hazard quotient (HQ) and hazard index (HI) values, respectively. The results revealed that individual exposure to each sample type did not have a significant impact on health (HQ < 1). However, simultaneous exposure to all of the sample types (soil, tomato and irrigation water) at the same time had a high likelihood of affecting health (HI > 1). The total carcinogenic concentrations of Cr, Cd, Ni, and Pb were greater than 1 × 10-4, revealing that farmers have a high probability of developing cancer during their lifetime. Minimizing simultaneous exposure to soil, tomato, and irrigated water for local people is highly recommended to prevent the risk of PTMs.

Comprehensive assessment of heavy metal contamination in soil-plant systems and health risks from wastewater-irrigated vegetables

A research study examined the origins, human health impacts, and risks associated with pollutants in vegetables grown in soil irrigated with wastewater. The study analyzed 164 samples from water sources, irrigated soil, and harvested vegetables for eight heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) using atomic absorption spectrophotometry. The focus was on the potential health effects of consuming heavy metal-contaminated vegetables grown in wastewater-irrigated soil. The findings revealed significant accumulation of heavy metals in soil and plants from Mianwali, Pakistan, posing potential health risks to consumers. When compared to vegetables produced with freshwater irrigation, the concentration levels of heavy metals in the soil irrigated with untreated wastewater were significantly greater (P≤0.001) and above the recommended limits set by the World Health Organization (WHO). The results showed that heavy metals in the soil had significantly increased, and crops had subsequently absorbed these metals. Produce raised in soil watered with wastewater showed higher levels of heavy metals than the US Environmental Protection Agency (EPA) and the WHO recommended. Among the veggies, lead (Pb) and cadmium (Cd) were found to have higher Hazardous Quotient Indices (HRIs) than one. This indicates that both adults and children may have been exposed to dangerous levels of these metals. Additionally, for Brassica oleracea, Raphanus sativus, and Spinacia oleracea, nickel (Ni) surpassed HRIs larger than 1, indicating a significant health risk connected to these veggies' ingestion.

A revised model of global silicate weathering considering the influence of vegetation cover on erosion rate

Abstract. Silicate weathering, which is of great importance in regulating the global carbon cycle, has been found to be affected by complicated factors, including climate, tectonics and vegetation. However, the exact transfer function between these factors and the silicate weathering rate is still unclear, leading to large model–data discrepancies in the CO2 consumption associated with silicate weathering. Here we propose a simple parameterization for the influence of vegetation cover on erosion rate to improve the model–data comparison based on a state-of-the-art silicate weathering model. We found out that the current weathering model tends to overestimate the silicate weathering fluxes in the tropical region, which can hardly be explained by either the uncertainties in climate and geomorphological conditions or the optimization of model parameters. We show that such an overestimation of the tropical weathering rate can be rectified significantly by parameterizing the shielding effect of vegetation cover on soil erosion using the leaf area index (LAI), the high values of which are coincident with the distribution of leached soils. We propose that the heavy vegetation in the tropical region likely slows down the erosion rate, much more so than thought before, by reducing extreme streamflow in response to precipitation. The silicate weathering model thus revised gives a smaller global weathering flux which is arguably more consistent with the observed value and the recently reconstructed global outgassing, both of which are subject to uncertainties. The model is also easily applicable to the deep-time Earth to investigate the influence of land plants on the global biogeochemical cycle.

Health risk assessment associated with consumption of heavy metal-contaminated vegetables: A case study in the southern area of Northeast Thailand

This study aims to determine the amount of lead exposure and investigate the health hazards linked to the consumption of leafy vegetables contaminated with lead and cadmium. It focuses on a specific case study conducted in the southern region of Northeast Thailand. Five types of leafy vegetables, including Chinese kale, cabbage, Chinese cabbage, lettuce, and parsley, were collected from the Southern Northeast region of Thailand. The vegetable consumption of 3,831 individuals was calculated. The results showed that Chinese kale had the highest average lead contamination (0.009±0.015 mg/kg DW), followed by Chinese cabbage (0.005±0.01 mg/kg DW), cabbage (0.004±0.003 mg/kg DW), lettuce (0.003±0.003 mg/kg DW), and parsley (0.001±0.01 mg/kg DW), respectively. The evaluation results indicated that the margin of safety values for leafy vegetable consumption ranged between 4.49731E-05 and 0.04550, suggesting no major health risks. Based on geographical information, the lowest altitude was 95 m in the Warin Chamrap District of Ubon Ratchathani Province, while the highest was 450 m in the Pak Chong District of Chum Klat, Nakhon Ratchasima Province. Therefore, people in the Southern Northeast region of Thailand should be encouraged to cultivate vegetables for their own consumption based on the season, and hydroponic systems should be utilized. It is important to assess and monitor the levels of heavy metals in the vegetables intended for consumptions and potential adverse effects on the environment and, consequently, human health. When choosing vegetables, it is advisable for consumers to exercise prudence and choose produce sourced from reputable cultivation facilities. Additionally, to prevent the accumulation of pollutants that could result in long-term health effects, it is prudent to vary their vegetable intake. The data obtained can be used in remediation techniques and to implement control measures for heavy metal contamination in vegetables.

Compact water pump and its application to self-contained soft robot hand for vegetable factory

As the number of agricultural workers is decreasing, there are a lot of demands on the robotics automation of agricultural tasks, including the automation of repacking and shipping in vegetable factories. A soft robot hand is suitable for such tasks because of its less damaging to vegetables and adaptability to variety in size and weight of vegetables. However, most of soft robotic hands are actuated by the air pressure, and the output force is not sufficient for heavy vegetables that are often dealt with in a vegetable factory. To solve this problem, we developed a prototype of a hydraulic soft robot hand in our previous research. Selecting an oil as the hydraulic source, the prototype was actuated by a compact built-in pump, we showed that the prototype could hold 2 or cabbage with pressure control. In this paper, we develop a compact water pump that can generate maximum , and update the prototype selecting the water as the hydraulic source. We experimentally show that the soft hand can grasp and hold a cabbages, assuming a real situation in a vegetable factory.

AN OUTBREAK OF SCRUB TYPHUS IN A REMOTE VILLAGE-AN OVERVIEW

Objective: An outbreak of scrub typhus was declared by Public Health authorities in our district in October, 2022. To investigate this a team of experts from Microbiology, SPM, Medicine and Pediatric Medicine was sent to the place of outbreak and they observed that there was heavy vegetation, stagnant water, dwellings heavily infested with rodent population. There was heavy rain in the past two weeks in the district. To investigate the cause of sudden upsurge of febrile illness cases.&#x0D; Methods: Blood samples were collected from 28 persons who were symptomatic with fever/headache/diarrhea/rash and myalgia to do tests for Scrub typhus, Typhoid fever, Malaria, Dengue, Complete blood count, CRP, LFT and KFT. The samples which were positive for Scrub typhus in rapid test kits were subjected for IgM ELISA to confirm scrub typhus.&#x0D; Results: Seven of twenty-eight patients tested positive for scrub typhus by rapid test (25%), and four of them were positive by IgM ELISA (14.28%). Three patients were Widal-positive (10.7%). More than half samples showed increased CRP levels (53.57%). Thrombocytopenia and mild leucocytosis was observed in scrub typhus cases (42.85%) as well as in typhoid cases.&#x0D; Conclusion: Any outbreak during monsoon should be investigated thoroughly not only for the specified disease but also for all infectious diseases that are prevalent in that area.

Progress of Mine Land Reclamation and Ecological Restoration Research Based on Bibliometric Analysis

The mining of mineral resources has caused serious damage to land and significant pressure on ecological environment. During the repairing of damaged land and degraded ecosystems, there have been many pieces of literature related to land reclamation and ecological restoration (LRER) that have emerged. To understand the progress and prospect of LRER research, it is necessary to sort out such pieces of literature, analyze the current research status, and forecast the future research directions. Here, Bibliometrix R-package was used to analyze 2357 articles, which were derived from the core database of Web of Science, to explore the development of LRER from 1990 to 2022. The results are as follows. (1) The annual scientific output results show that both the number of articles published on LRER and the number of articles annually citied were increasing gradually from 1990 to 2022. (2) High-frequency keyword analysis indicates that heavy metal (Cd, Pb) pollution remediation is a research hotspot. The cluster analysis (CA) and multiple correspondence analysis (MCA) show that there are two clusters in the current research of LRER, in which one surrounds heavy metal pollution and the other focuses on ecological restoration of mining areas. The two clusters correspond to the remediation and ecological restoration (rehabilitation) stages of stepwise ecological restoration, respectively. Thematic evolution analysis shows that, for more than 30 years, mine drainage and heavy metal pollution treatment, soil reconstruction (soil profile reconstruction, soil improvement), and vegetation restoration have been the focus of research. (3) Future research should focus on the relationship between mine ecological restoration and carbon sequestration and the relationship between ecological restoration and biodiversity in mine areas. In addition, LRER technology exchange, international cooperation, and industrialization are also main directions of development. Generally, in this study, metrology software (Bibliometrix R-package 3.1.4) from the literature was used to sort out the relevant literature on LRER over the past 30 years so as to provide reference for future research on LRER.

Role of the rhizosphere bacterial community in assisting phytoremediation in a lead-zinc area.

Heavy metals (HMs) contamination and vegetation destruction in the mining area caused by mining activities are severely increasing. It is urgent to restore vegetation and stabilize HMs. In this study, we compared the ability of HMs phytoextraction/phytostabilization of three dominant plants, including Artemisia argyi (LA), Miscanthus floridulus (LM), and Boehmeria nivea (LZ) in a lead-zinc mining area in Huayuan County (China). We also explored the role of the rhizosphere bacterial community in assisting phytoremediation using 16S rRNA sequencing technology. Bioconcentration factor (BCF) and translocation factor (TF) analysis showed that LA preferred accumulating Cd, LZ preferred accumulating Cr and Sb, and LM preferred accumulating Cr and Ni. Significant (p < 0.05) differences were found among the rhizosphere soil microbial communities of these three plants. The key genera of LA were Truepera and Anderseniella, that of LM were Paracoccus and Erythrobacter, and of LZ was Novosphingobium. Correlation analysis showed some rhizosphere bacterial taxa (e.g., Actinomarinicola, Bacillariophyta and Oscillochloris) affected some soil physicochemical parameters (e.g., organic matter and pH) of the rhizosphere soil and enhanced the TF of metals. Functional prediction analysis of soil bacterial community showed that the relative abundances of genes related to the synthesis of some proteins (e.g., manganese/zinc-transporting P-type ATPase C, nickel transport protein and 1-aminocyclopropane-1-carboxylate deaminase) was positively correlated with the phytoextraction/phytostabilization capacity of plants for heavy metals. This study provided theoretical guidance on selecting appropriate plants for different metal remediation applications. We also found some rhizosphere bacteria might enhance the phytoremediation of multi-metals, which could provide a reference for subsequent research.

Differential responses of hydrochemical factors and LULC changes on the spatial and temporal hydrogeochemistry of the eco-sensitive Baraila wetland, Bihar, India.

Freshwater scarcity, deterioration and associated water management remain to be one of the most challenging aspects of high-population density economies especially in subtropical/tropical regions. The present research deals with hydrogeochemical analysis of the eco-sensitive Baraila wetland and possible sources of anthropogenic pollution. The hydrochemical characterization was performed in GIS environment, considering meteorologically induced parameters and spatial variability. Temporal variations were assessed through different seasons, namely pre-monsoon, monsoon and post-monsoon with the help of multivariate statistics. The changes in water depth across the seasons showed significant hydrochemical variations in the vertical profile of the wetland apart from thermal demarcation. Seasonal variations in the hydrogeochemistry were induced by multiple physicochemical parameters, geochemical processes, geomorphology of the surrounding area and land use and land cover (LULC) changes. The pre-post flooding changes revealed that aquatic vegetation was increased by 15.36% whereas a major decrease in water bodies (- 73.2%) occurred. Dissolved oxygen (DO), pH, temperature and carbonates are fundamental towards establishing wetland's water chemistry. The water type is primarily of Ca-HCO3 type, mostly derived from rock-water interactions and cation exchange processes. Irrigational quality of water was assessed through multiple indices (sodium adsorption ratio (SAR), %Na, residual sodium carbonate (RSC), magnesium hazard (MH) and total hardness (TH)) and plots. The heavy aquatic vegetation abundance and eutrophication because of agricultural run-off is currently the major issue with the Baraila wetland and may be playing a simultaneous role in regulating the water chemistry to a large extent apart from other geochemical processes. The hydrogeochemical interactions between sediment and overlying water have created distinct effects on biota and land use/land cover changes. Their role in the landscape is prominent in this respect and may be utilized for environmental management, eco-tourism and employment boost. Serious lack of hydrogeochemical studies in this important floodplain wetland and its rapid deterioration deems it necessary to focus on the comprehensive research and wetland management options for its conservation and sustainable usage in future.

Sentinel-1 InSAR and GPS-Integrated Long-Term and Seasonal Subsidence Monitoring in Houston, Texas, USA

For approximately 100 years, the Houston region has been adversely impacted by land subsidence associated with excessive groundwater withdrawals. The rapidly growing population in the Houston region means the ongoing subsidence must be vigilantly monitored. Interferometric synthetic aperture radar (InSAR) has become a powerful tool for remotely mapping land-surface deformation over time and space. However, the humid weather and the heavy vegetation have significantly degraded the performance of InSAR techniques in the Houston region. This study introduced an approach integrating GPS and Sentinel-1 InSAR datasets for mapping long-term (2015–2019) and short-term (inter-annual, seasonal) subsidence within the greater Houston region. The root-mean-square (RMS) of the detrended InSAR-displacement time series is able to achieve a subcentimeter level, and the uncertainty (95% confidence interval) of the InSAR-derived subsidence rates is able to achieve a couple of millimeters per year for 5-year or longer datasets. The InSAR mapping results suggest the occurrence of moderate ongoing subsidence (~1 cm/year) in nothwestern Austin County, northern Waller County, western Liberty County, and the city of Mont Belvieu in Champers County. Subsidence in these areas was not recognized in previous GPS-based investigations. The InSAR mapping results also suggest that previous GPS-based investigations overestimated the ongoing subsidence in southwestern Montgomery County, but underestimated the ongoing subsidence in the northeastern portion of the county. We also compared the InSAR- and GPS-derived seasonal ground movements (subsidence and heave). The amplitudes of the seasonal signals from both datasets are comparable, below 4 mm within non-subsiding areas and over 6 mm in subsiding (&gt;1 cm/year) areas. This study indicates that groundwater-level changes in the Evangeline aquifer are the primary reason for ongoing long-term and seasonal subsidence in the Houston region. The former is dominated by inelastic deformation, and the latter is dominated by elastic deformation. Both could cause infrastructure damage. This study demonstrated the potential of employing the GPS- and InSAR-integrated method (GInSAR) for near-real-time subsidence monitoring in the greater Houston region. The near-real-time monitoring would also provide timely information for understanding the dynamic of groundwater storage and improving both long-term and short-term groundwater resource management.

Characterization of vegetation and the arbuscular mycorrhizal fungi community in soils impacted by gold mining in Colombia

Mining extraction has a substantial impact on soil and vegetation cover. However, little is known about its effect on the flora and microorganisms associated with these environments. Arbuscular Mycorrhizal Fungi (AMF) form associations with plants, improving their development in environments contaminated with heavy metals, among other benefits. Native plants and AMF found in the soil degraded by mining play an essential role in establishing programs dealing with recovering areas influenced by these activities. Therefore, this study aimed to characterize vegetation and AMF abundance and diversity in an area affected by gold mining in Colombia. Vegetation was evaluated in two areas, one adjacent to mining deposits with native vegetation (SI-N) and the other in an intermediate area with mining waste and initial natural plant successions (SI-SV). AMF was assessed in the SI-N and the mining waste area (SI-M). Vegetation was quantified using the RAP method, and AMF was assessed using wet sieving from direct soil samples and trap crops. Vegetation evaluations identified 605 individuals belonging to 29 families, 46 genera, and 54 species, and AMF assessment identified 11 species and five genera. Diversity was established using Hill numbers, finding that SI-N was more diverse for vegetation (Q1: 11.94) and SI-M for AMF (Q1: 3.07). Heavy metals and vegetation decreased the diversity and abundance of AMF in the SI-M. Plant species of the genera Baccharis, Agrostis, Miconia, and the AMF Glomus microcarpum were the most frequent species with potential for recovery in degraded areas.

Remote sensing for monitoring the impacts of agroforestry practices and precipitation changes in particle size export trends

Recent land use changes, the absence of soil protection between crop periods, and extreme precipitation events have been highlighted as major influential factors in the fluctuations of sediment export in the last decades at the catchment scale worldwide. In this regard, soil erosion and fine-particle export are two of the major concerns of soil nutrient loss and water-quality decrease (e.g., increasing turbidity and vector of chemicals). However, while rainfall effects have been well-monitored, recent land use changes and management need additional approaches to evaluate their effect. In Mediterranean mountainous environments, in addition to forest management, agricultural practices during different cropland stages likely increase sediment and particle-bound chemicals in the drainage system. Moreover, most catchments lack instrumentalization. Thus, there is a gap in the knowledge on the processes influencing the sediment exported in ungauged catchments. To evaluate the processes involved, remote sensing and seasonal sampling of suspended sediments were examined for 5 years in a representative agroforestry system in three sub-catchments (SBCs) with different proportions of land uses. Temporal trends of NDVI, EVI, MSAVI, SAVI, and NDWI indices were analyzed for monitoring the vegetation status. With this information, we attempt to evaluate the soil response in terms of particle size export to land use change, vegetation status, and precipitation distribution in fine-grained sediment-reaching streams. Our findings not only highlight the significant effect of heavy precipitation events and vegetation cover on the grain-size fraction of the exported sediment but also reveal the existence of more complex factors influencing the export dynamics. A silt-increasing trend due to the increase of individual heavy precipitations from 2017 onward despite the total precipitation amount not increasing was detected. It is shown that indices such as NDVI and NDMI help detect small changes in vegetation cover, while EVI, SAVI, and MSAVI are more robust for detecting general patterns in large vegetated areas and preventing the appearance of artefacts in the data. Results from this study suggest that land use changes combined with short-scale changing trends of rainfall likely explain most of the possible effects observed in terms of sediment export changes.

Investigating the Effects of Snow Cover and Vegetation on Soil Temperature Using Remote Sensing Indicators in the Three River Source Region, China

Soil temperature is an important physical variable that characterises geothermal conditions and influences geophysical, biological and chemical processes in the earth sciences. Soil temperature is not only affected by climatic and geographical factors; it is also modulated by local factors such as snow cover and vegetation. This paper investigates the relationship between snow cover and vegetation and soil temperature with the help of two classical remote sensing indicators, the Snow Cover Days (SCD) based Advanced Very High Resolution Radiometer and the Normalized Difference Vegetation Index (NDVI)-based Global Inventory Modelling and Mapping Studies, to analyse the influence of local factors on soil temperature in the Three River Source Region (TRSR). Combing multi-layer geothermal observations from 23 stations in the TRSR with meteorological dataset, soil properties datasets, snow cover and vegetation indices, a non-linear model, the Random Forest model, is used to establish a multi-layer soil temperature dataset to analyse the influence of surface cover factors in each depth. The results showed that the annual SCD had a decreasing trend during 1982–2015 and was negatively correlated with the annual mean soil temperature; the annual NDVI had no significant trend, but it was positively correlated with the annual mean soil temperature. Regionally, there was a significant decrease in SCD in the mountainous areas bordering the source areas of the three rivers, and there was a trend of increasing NDVI in the northwest and decreasing vegetation in the southwest in the TRSR. The stronger the correlation with soil temperature in areas with a larger SCD, the more the snow has a cooling effect on the shallower soil temperatures due to the high albedo of the accumulated snow and the repeated melting and heat absorption of the snow in the area. The snow has an insulating effect on the 40 cm soil layer by impeding the cooling effect of the atmosphere in winter. In sparsely vegetated areas, vegetation lowers ground albedo and warms the soil, but in July and August, in areas with more vegetation, NDVI is negatively correlated with soil temperature, with heavy vegetation intercepting summer radiant energy and having a cooling effect on the soil.

Rhizosphere Microbial Communities and Geochemical Constraining Mechanism of Antimony Mine Waste-Adapted Plants in Southwestern China.

Antimony (Sb) and arsenic (As) are two hazardous metalloid elements, and the biogeochemical cycle of Sb and As can be better understood by studying plant rhizosphere microorganisms associated with Sb mine waste. In the current study, samples of three types of mine waste—Sb mine tailing, waste rocks, and smelting slag—and associated rhizosphere microorganisms of adapted plants were collected from Qinglong Sb mine, southwest China. 16S rRNA was sequenced and used to study the composition of the mine waste microbial community. The most abundant phylum in all samples was Proteobacteria, followed by Bacteroidota, Acidobacteriota, and Actinobacteriota. The community composition varied among different mine waste types. Gammaproteobacteria was the most abundant microorganism in tailings, Actinobacteria was mainly distributed in waste rock, and Saccharimonadia, Acidobacteriae, and Ktedonobacteria were mainly present in slag. At the family level, the vast majority of Hydrogenophilaceae were found in tailings, Ktedonobacteraceae, Chthoniobacteraceae, and Acidobacteriaceae (Subgroup 1) were mostly found in slag, and Pseudomonadaceae and Micrococcaceae were mainly found in waste rock. Actinobacteriota and Arthrobacter are important taxa for reducing heavy metal(loid) mobility, vegetation restoration, and self-sustaining ecosystem construction on antimony mine waste. The high concentrations of Sb and As reduce microbial diversity.

Use of fans and their effects on the turf microenvironment and disease development

AbstractCommon turf management practices such as close mowing, high fertilization rates, and frequent watering, in combination with stressful environmental conditions, can cause creeping bentgrass (Agrostis stolonifera L.) golf greens to decline during the summer months in warm humid climates. Conditions that prevent the natural movement of air across a putting surface can contribute to severe disease problems. Electric fans are being used to provide increased airflow across putting greens on many golf courses. The objectives of this study were to determine if fans could reduce brown patch (Rhizoctonia solani) disease incidence by altering the microenvironment at the canopy surface and reduce canopy temperature and leaf wetness duration and improve turf quality. The study was conducted on a mature stand of creeping bentgrass surrounded by heavy vegetation that impeded the natural movement of air across the putting surface. Fans were used to supplement ambient wind with up to 2.7 m s−1 air velocity across the experiential plots. Three 372‐W, 35.5‐cm diameter nonoscillating fans were used and operated continuously throughout the study. As wind velocity increased, turf canopy temperatures decreased. Average canopy temperatures were 28 °C at 2.7 m s−1 and 32 °C at 0.3 m s−1. Duration of leaf wetness also decreased as wind speed increased. Average disease incidence ranged from 11 to 33% at the lowest velocities, and 0 to 7% in plots with the highest wind velocities. Results indicate that using fans on creeping bentgrass golf greens significantly affected the microclimate and disease severity was reduced with higher wind velocities.

中国-中东欧国家森林生态系统研究重点对比及合作方向分析——基于文献计量研究

PDF HTML阅读 XML下载 导出引用 引用提醒 中国-中东欧国家森林生态系统研究重点对比及合作方向分析——基于文献计量研究 DOI: 10.5846/stxb202107131880 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 中国-中东欧林业合作联合研究中心平台构建(2018Q00161) Focus of forest ecosystem research and cooperation direction between China and the Central and Eastern European countries based on bibliometric research Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:中国-中东欧国家林业合作(17+1林业合作)是中国-中东欧国家合作的重要组成部分。为了明确双方林业研究的重点,使17+1林业合作更有针对性的开展,通过比较中国和中东欧17国森林生态系统研究状况,探究中国和中东欧17国森林生态系统研究的共同方向和领域,为中国-中东欧国家林业合作提供支撑。采用文献计量分析软件Citespace和VOSviewer对Web of Science核心库收录的中国和中东欧17国在2016-2020年期间发表的论文进行比较分析,内容涵盖国家、研究机构、作者、关键词的共现分析和关键词突现分析。分析结果显示:①中东欧17个国家之间的森林生态系统研究论文发表状况差异明显,其中波兰和捷克两国在森林生态系统研究领域发表论文数量最多,发文量分别占中东欧国家发文总量的26.91%和23.52%,篇均被引频次分别为8.46次/篇和9.85次/篇。②中国森林生态系统研究发表论文数量12951篇,高于中东欧国家总和8952篇,篇均被引用频次为8.58次/每篇,低于中东欧国家平均值9.90次/篇。③气候变化、生物多样性、森林土壤是中国与中东欧国家共同的研究重点。④中国的研究重点还包括人工林质量改善等。中东欧国家的研究重点还包括重金属,主要表现在重金属污染、评估及土壤和植被修复。通过对中国和中东欧国家森林生态系统研究领域发表的论文分析,为中国与中东欧国家林业合作提供以下建议:中国与中东欧国家开展林业研究合作,在气候变化方面的合作对象有波兰科学院、华沙大学、捷克生命科学大学;生物多样性方面的合作对象有捷克生命科学大学、捷克科学院、波兰科学院;土壤微生物方面的合作对象有塔尔图大学、波兰科学院;土壤重金属方面研究的合作对象有克拉科夫农业大学、波兰科学院、波兰格但斯克大学;病虫害防治方面的合作对象有捷克生命科学大学。 Abstract:China-CEEC (the Central and Eastern European countries) forestry cooperation, also known as 17+1 forestry cooperation, is an important part of China-CEEC cooperation. To clarify the focus of forestry research between the two parties and make the 17+1 forestry cooperation more targeted, this study explored the common direction and field of forest ecosystem research between China and the 17 countries in the Central and Eastern Europe by comparing their forest ecosystem research status. The purpose of the research is to provide support for China-CEEC forestry cooperation. In this paper, citation spatial analysis tool (Citespace and VOSviewer) were used to compare and analyze the papers that had been published in China and 17 countries in Central and Eastern European and included in the Web of Science Core Collection during 2016—2020. The dataset covers countries, research institutions, authors, keyword co-occurrence analysis and burst keyword analysis. The results show that: ①the number of published papers on forest ecosystem research among 17 countries in the Central and Eastern Europe are obviously different. Among them, Poland and the Czech Republic published the most papers in the field of forest ecosystem research, accounting for 26.91% and 26.91% of the total number of papers published by the CEEC. The articles of the two countries are cited 8.46 times/article and 9.85 times/ article, respectively. ② The number of forest ecosystem research papers published by China is 12951, which is higher than the total number of 8952 papers in the CEEC, and the citation of each article is 8.58 times, which is lower than the average of 9.90 times/article in the CEEC. ③Climate change, biodiversity, and forest soil are the common research priorities of China and Central and Eastern European countries. ④China’s research priorities also include improving the quality of plantation forests. The research priorities of the CEEC also include heavy metals, which are mainly manifested in heavy metal pollution, assessment, and soil and vegetation restoration. Based on the analysis of papers published in the forest ecosystem research field of China and the CEEC, the research provides the following suggestions for forestry cooperation between China and The CEEC: For China, the partners in climate change include the Polish Academy of Sciences, the University of Warsaw, and Czech University of Life Sciences; the partners in biodiversity include the Czech University of Life Sciences, the Czech Academy of Sciences, and the Polish Academy of Sciences; the partners in soil microbiology are the University of Tartu, the Polish Academy of Sciences; The partners in soil heavy metals are Krakow Agricultural University, the Polish Academy of Sciences, and the University of Gdansk in Poland; the partners in the pest control is the Czech University of Life Sciences. 参考文献 相似文献 引证文献

Effect of Vegetation Cover and Shading on Thermal and Visual Comfort in Institutional Campus Outdoor Spaces in India

This paper investigates the phenomenon of Urban Heat Island (UHI) in open spaces that when combined creates a problem at a city level. This paper will primarily focus on institutional campuses, wherein open spaces play a vital role for each and every user for interaction and other purposes. When architects and urban designers deal with the physical properties of a space, and therefore modify its material, thermal, and lighting characteristics, they influence the social environment as well. The method used in this study is the analysis of secondary data available so far. The aim of the study is to understand the UHI phenomenon in urban public spaces and suggest measures that would help mitigate the same and make it a better space in terms of comfort. It includes off-site measurement of climatic conditions on particular given day and observations of student behavior in the public spaces. The result is obtained by ENVImet software simulation in the case study area of DCRUST university campus in Murthal, Haryana. The study area is located in the North part of India and has composite climate. This paper refers to research results showing the comparison of various cases that can be designed in an urban open space and with the help of simulation it shows the best combination to be used and how that combination changes the open space design by improving thermal comfort. It shows that in composite climate, the strategy of implementing thick and heavy foliage vegetation in combination with the water body (such as artificial ponds, swales, pits etc.) causing evaporative cooling that in return enhances the microclimatic environment and visual comfort for pedestrian walkability, usability of the open space and by acting against the anthropogenic heat.

Sauaeda Fruticusa is Hyperaccumulator of Chromium and Lead

Sauaeda Fruticusa is Hyperaccumulator of Chromium and Lead

Comparison of 3D scan matching techniques for autonomous robot navigation in urban and agricultural environments

Global navigation satellite system (GNSS) is the standard solution for solving the localization problem in outdoor environments, but its signal might be lost when driving in dense urban areas or in the presence of heavy vegetation or overhanging canopies. Hence, there is a need for alternative or complementary localization methods for autonomous driving. In recent years, exteroceptive sensors have gained much attention due to significant improvements in accuracy and cost-effectiveness, especially for 3D range sensors. By registering two successive 3D scans, known as scan matching, it is possible to estimate the pose of a vehicle. This work aims to provide in-depth analysis and comparison of the state-of-the-art 3D scan matching approaches as a solution to the localization problem of autonomous vehicles. Eight techniques (deterministic and probabilistic) are investigated: iterative closest point (with three different embodiments), normal distribution transform, coherent point drift, Gaussian mixture model, support vector-parametrized Gaussian mixture and the particle filter implementation. They are demonstrated in long path trials in both urban and agricultural environments and compared in terms of accuracy and consistency. On the one hand, most of the techniques can be successfully used in urban scenarios with the probabilistic approaches that show the best accuracy. On the other hand, agricultural settings have proved to be more challenging with significant errors even in short distance trials due to the presence of featureless natural objects. The results and discussion of this work will provide a guide for selecting the most suitable method and will encourage building of improvements on the identified limitations.