Geo-environmental impact assessment of Jinshazhou area in Guangzhou City

The geo-environmental impact of anthropogenic activities in Jinshazhou area is predicted by assessing the geo-environmental problems susceptibility under the condition of nature and anthropogenic activities in the study. An evaluation factor system including natural and anthropogenic factors is setup and the principal component analysis-fuzzy comprehensive evaluation model is selected. Results are shown in four grades, including very low, low, high, and very high. Under the natural condition, the very low, low, high, and very high susceptible regions of geo-environmental problems take up 67.73%, 0.71%, 7.30%, and 24.26%, respectively. Under the condition of anthropogenic activities, the very low, low, high, and very high susceptible regions of geo-environmental problems take up 69.18%, 5.88%, 5.88%, and 19.06%, respectively. Comparing the susceptibility of geo-environmental problems under two conditions, it can be predicted that there is a greatly negative impact of anthropogenic activities in the southern surrounding region of Jinshazhou tunnel; while in the north of the study area, such as Poly West Coast, anthropogenic activities have a positive impact on geo-environment. The present distribution of geo-environmental problems has shown that the new evaluation technique system can be successfully applied to predict the urban geo-environmental impact of anthropogenic activities.     

Origin and potential ecological risk assessment of trace elements in the watershed topsoil and coastal sediment of the Oualidia lagoon,Morocco

The Oualidia lagoon provides important ecosystem services, such as fishing, aquaculture, tourism and high biological and ecological productivity. Many indices have been developed to evaluate environmental risks and to estimate the anthropogenic contribution of potentially toxic elements (PTE) in surficial sediments. The results show that the concentrations of the PTE found in surface sediments due to the anthropogenic activities in the area (urban effluents, aquaculture and agricultural areas) are significantly higher than those from the local background and sediment quality guidelines (SQGs). The potential ecological and biological risk index present satisfactory results. However, the sites near to the areas where anthropogenic activities are developed present 49% probability of toxicity, while the rest of the lagoon, present 9% to 21% probability of toxicity and low potential ecological risk, except for Hg where the risk was considered to be considerable. The PTE are mainly originated from the anthropogenic activities; nevertheless, anthropogenic contributions represent up to 69% of the total sediment of content, but it depends on the PTE: Cd (16%), Ni (38%), Zn (41%), Cr (43%), Cu (56%), Hg (68%), Pb (69%). Compared with the Sub-basin soils, the PTE are higher than 80%, hence the sub-basin feeds the lagoon by these elements (PTE).     

Anthropogenic activities change the relationship between microbial community taxonomic composition and functional attributes

Functional redundancy is considered common in microbial systems, but recent studies have challenged this idea. The mechanism for this contradictory result is not clear. However, in this study, we hypothesize that strong environmental filtering which links to the anthropogenic activities is able to weaken microbial functional redundancy. We used metagenome and 16S rRNA gene high-throughput sequencing to investigate planktonic microbial communities in a subtropical river. We found that the weak anthropogenic activities might result in a low selection pressure in the river upstream area. Therefore, the microbial community functional attributes were stable although the community composition changed with the water temperature and NO₃-N in upstream area (this indicates functional redundancy). However, the strong anthropogenic activities in river downstream area selected pollutant-degraded functions (e.g. nitrogen metabolism, toluene, xylenes and ethylbenzene degradation) and potentially pollutant-degraded (tolerant) microbes, and therefore caused the microbial community composition synchronously changed with the variation of community functional attributes. Our results reveal that strong environmental filtering which associates with the anthropogenic activities not only has effects on microbial community composition and community functional attributes but also on their relationships. These results provide a new insight to refine the functional redundancy idea.     

The Impact of Human Activities on Biological Evolution: A Topic of Consideration for Evolution Educators

There is a definitive need, at all science education levels, to strongly emphasize the central anthropogenic role humans now play in current evolutionary processes and biosphere impact. This article presents a brief overview of recent human activities; broad examples of the impact of human activities on biological evolution; a general overview and specific examples of incorporating human activities into evolution education; and further online anthropogenic resources that can be incorporated into educational settings.     

Linking Water Quality and Quantity in Environmental Flow Assessment in Deteriorated Ecosystems: A Food Web View

Most rivers worldwide are highly regulated by anthropogenic activities through flow regulation and water pollution. Environmental flow regulation is used to reduce the effects of anthropogenic activities on aquatic ecosystems. Formulating flow alteration–ecological response relationships is a key factor in environmental flow assessment. Traditional environmental flow models are characterized by natural relationships between flow regimes and ecosystem factors. However, food webs are often altered from natural states, which disturb environmental flow assessment in such ecosystems. In ecosystems deteriorated by heavy anthropogenic activities, the effects of environmental flow regulation on species are difficult to assess with current modeling approaches. Environmental flow management compels the development of tools that link flow regimes and food webs in an ecosystem. Food web approaches are more suitable for the task because they are more adaptive for disordered multiple species in a food web deteriorated by anthropogenic activities. This paper presents a global method of environmental flow assessment in deteriorated aquatic ecosystems. Linkages between flow regimes and food web dynamics are modeled by incorporating multiple species into an ecosystem to explore ecosystem-based environmental flow management. The approach allows scientists and water resources managers to analyze environmental flows in deteriorated ecosystems in an ecosystem-based way.     

Biomarker/bioindicator response profiles of organisms can help differentiate between sources of anthropogenic stressors in aquatic ecosystems

Aquatic ecosystems can be chronically stressed by multiple environmental factors which originate from a variety of point and non-point sources. In addition, these stressors may vary both spatially and temporally, and, combined with synergestic and cumulative interactions of these stressors, complicate the interpretation and evaluation of stress responses in organisms. To help identify and differentiate between sources of anthropogenic stressors in aquatic systems, a diagnostic approach based on exposure-response profiles in sentinel organisms was developed from the known effects of various anthropogenic activities on biological systems. To generate these exposure-effects profiles, biomarkers of exposure were plotted against bioindicators of corresponding effects for several major anthropogenic activities including petrochemical, pulp and paper, domestic sewage, mining operations, land-development, and agricultural activities. Biomarkers of exposure to environmental stressors varied widely depending on the type of anthropogenic activity involved. Bioindicator effects, however, including histopathological lesions, bioenergetic status, growth, reproductive impairment, and community-level endpoints were similar among several of the major anthropogenic activities because responses at these higher levels are less specific to stressors than are biomarkers. This approach appears useful for helping to identify and diagnose sources of stress in environments impacted by multiple stressors. By identifying the types and sources of environmental stressors impacting key components of biological systems, aquatic ecosystems can be more effectively protected, regulated, and managed to help improve and maintain environmental quality and ecosystem fitness.     

Impact of climatic changes and anthropogenic activities on ecosystem net primary productivity in India during 2001–2019

Climate change and anthropogenic activities have altered the terrestrial ecosystem dynamics around the globe. Due to the complex ecosystem-atmosphere interactions at different scales, these impacts are difficult to quantify and are poorly understood, especially in developing countries with limited ground-based observations. This study analyzed the impact of climatic changes and anthropogenic activities on ecosystem net primary productivity (NPP) in India using remote sensing-based observations, correlation analysis, and Residual Trend analysis (RESTREND). Using different climate variables such as precipitation, temperature, and solar radiation, along with Land Use and Land Cover (LULC) and NPP maps, we first classified the ecosystems (ES) into two categories: natural ecosystems – influenced only by climate change (ES_c), covering about 19.7% of the area, and human-influenced ecosystems – influenced by both climate change and anthropogenic activities (ES_c+a), covering about 80.3% of the area. RESTREND analysis was performed on both ES_c and ES_c+a to analyze the relative contributions of climate change and human activities to changes in NPP. The correlation analysis between NPP and climate variables suggested that precipitation was the dominant control of NPP in about 72% area, whereas temperature and solar radiation controlled NPP in Himalayan and forest-dominated regions, respectively. The human-influenced ecosystems (ES_c+a) experienced an increasing trend in NPP, whereas natural ecosystems (ES_c) experienced a decreasing trend, particularly in forest-dominated regions. Overall, NPP increased in the country during the study duration. The contributions of climatic changes and anthropogenic activities varied spatially and temporally. In general, climatic factors enhanced the NPP, whereas human activities contributed to a slight decline in NPP. These findings improve our understanding of how ecosystems in India are influenced by climate change and anthropogenic activities in recent decades. The results from this study will aid in identifying ecological hotspots and key drivers for better ecosystem management strategies.     

基于CENTURY模型研究干旱区人工绿洲开发与管理模式变化对土壤碳动态的影响

近半个世纪前,中国西北干旱区人类大规模的水土开发活动使得流域下部的荒漠覆被土地转变成了人工绿洲,强烈的人类耕作活动使得人工绿洲土壤有机碳库发生了显著变化。以干旱区典型的三工河流域下部的人工绿洲为例,基于CENTURY模型,研究人工绿洲开发前后及农业管理模式变化对表层土壤有机碳库(0-20cm)的影响。CENTURY模型模拟结果表明:(1)研究区荒漠灌木林地开垦为人工绿洲后,在最初的2a土壤总有机碳(TOC)快速增加,随后呈逐渐下降的趋势;(2)研究区人工绿洲在被开发后50a的连续耕作下,平均土壤TOC呈先增后减再增的"N"型变化趋势,但最终土壤TOC超过了原始自然状态下的TOC,而且2008年土壤TOC比原始荒漠状态增加7.74%,说明研究区表层土壤有机碳总体呈"碳汇"趋势。尤其在研究区实施了免耕、秸秆粉碎还田、科学测土配方施肥等保护性耕作措施后,土壤固碳效应明显,这完全不同于热带森林、中国北部温带半干旱草原及非洲Savanna半干旱稀树草原开垦为耕地后土壤有机碳大量损失的结论。     

固体介质中的重金属源解析及其在中国近海沉积物中的应用

沉积物中重金属源解析对甄别人为活动与自然变化对近海生态系统演化的影响有重要作用.本文总结了近年来污染物源解析常用的多元统计分析、地球化学方法和地质统计分析3种主要研究方法,剖析了不同方法的优劣及适用性,提出正定矩阵因子分析、Pb同位素示踪在重金属来源定量化研究中具有良好应用前景.梳理了中国近海沉积物中重金属来源的主要研究结果,发现河口和海湾是沉积物重金属受人为来源影响剧烈的典型近海区域,不同定量解析方法(多元统计分析、背景值估算、Pb同位素分析)均表明中国近海沉积物重金属的人为来源贡献率接近或超过50%.当前中国近海沉积物中重金属源解析研究还存在源识别端元模糊、解析结果缺乏相应的可靠性评价等问题.据此提出近海沉积物重金属源解析研究应使用多种解析技术手段综合、集成与优化,提高源解析的准确性;建立完善指标体系,筛选代表特定人为活动和自然过程的指标;甄别人为源重金属入海方式及过程,为沉积物数据信息的解译提供理论基础.     

Anthropogenic chemicals and their impacts on microbes living in buildings

Humans spend the vast majority of their time indoors where complex interactions occur among indoor anthropogenic chemicals, indoor microbiomes and human occupants. This paper summarizes previous work addressing interactions between anthropogenic chemicals associated with indoor household products and building materials, and microorganisms found within the built environment. Water availability seems to determine the extent to which microbes are impacted by anthropogenic chemicals, since desiccation remains one of the primary stressors regulating microbial viability indoors. Several lines of evidence suggest that both fungi and bacteria are capable of transforming biodegradable ingredients originating from various products used indoors when water is present. Previous research also establishes positive and significant correlations between anthropogenic chemicals that are antimicrobial and antibiotic resistance gene abundance. As researchers move towards understanding complex indoor environments as well as the role of anthropogenic chemicals in shaping microbiomes, in situ activities associated with the viable indoor microbial population merit more attention.     

The effects of suspended sediment on coral reef fish assemblages and feeding guilds of north-west Australia

Coral Reefs - Understanding environmental drivers of fish assemblage composition is fundamental to designing useful management plans for anthropogenic activities. This study investigated the...     

宁夏东部荒漠草原向灌丛地人为转变过程中土壤胞外酶活性响应

以宁夏东部荒漠草原-灌丛地典型镶嵌体内部荒漠草地、草地边缘、灌丛边缘、灌丛地为对象,对各样地植丛和空斑下土壤特性及6种土壤胞外酶活性(纤维二糖水解酶、β-1,4-木糖苷酶、β-1,4葡萄糖苷酶、β-1,4-乙酰基氨基葡萄糖苷酶、亮氨酸氨基肽酶和碱性磷酸酶)进行分析,研究荒漠草原向灌丛地人为转变过程中胞外酶的响应特征。结果表明: 荒漠草原向灌丛地转变过程中,土壤水分、有机碳、全氮、全磷、微生物生物量碳、微生物生物量氮均显著降低,且灌丛地显著低于草地26.0%～88.5%;除草地边缘土壤水分、有机碳空斑略高于植丛外,其他指标均表现为各样地植丛显著高于空斑3.9%～82.3%。6类土壤胞外酶活性在转变过程中均呈下降趋势,降幅为22.1%～82.4%,其中亮氨酸氨基肽酶和碱性磷酸酶降低最为显著,分别降低82.4%和75.5%;除灌丛地β-1,4-乙酰基氨基葡萄糖苷酶在空斑显著高于植丛外,其他胞外酶活性均表现为各样地植丛高于空斑10.7%～42.7%;转变过程中6类胞外酶活性之间呈显著正相关,且均与土壤特性呈不同程度正相关,其中各类土壤胞外酶活性对土壤微生物生物量碳、氮及全氮响应较为积极。     

Three decades of recurrent declines and recoveries in corals belie ongoing change in fish assemblages

Coral Reefs - Coral reefs are increasingly being altered by a myriad of anthropogenic activities and natural disturbances. Long-term studies offer unique opportunities to understand how multiple...     

Elements of metacommunity structure in Amazonian Zygoptera among streams under different spatial scales and environmental conditions

An important aspect of conservation is to understand the founding elements and characteristics of metacommunities in natural environments, and the consequences of anthropogenic disturbance on these patterns. In natural Amazonian environments, the interfluves of the major rivers play an important role in the formation of areas of endemism through the historical isolation of species and the speciation process. We evaluated elements of metacommunity structure for Zygoptera (Insecta: Odonata) sampled in 93 Amazonian streams distributed in two distinct biogeographic regions (areas of endemism). Of sampled streams, 43 were considered to have experienced negligible anthropogenic impacts, and 50 were considered impacted by anthropogenic activities. Our hypothesis was that preserved (“negligible impact”) streams would present a Clementsian pattern, forming clusters of distinct species, reflecting the biogeographic pattern of the two regions, and that anthropogenic streams would present random patterns of metacommunity, due to the loss of more sensitive species and dominance of more tolerant species, which have higher dispersal ability and environmental tolerance. In negligible impact streams, the Clementsian pattern reflected a strong biogeographic pattern, which we discuss considering the areas of endemism of Amazonian rivers. As for communities in human‐impacted streams, a biotic homogenization was evident, in which rare species were suppressed and the most common species had become hyper‐dominant. Understanding the mechanisms that trigger changes in metacommunities is an important issue for conservation, because they can help create mitigation measures for the impacts of anthropogenic activities on biological communities, and so should be expanded to studies using other taxonomic groups in both tropical and temperate systems, and, wherever possible, at multiple spatial scales.     

高黎贡山土壤微生物生态分布及其生化特性的研究

研究了高黎贡山东坡不同海拔高度的自然林、不同海拔高度和人为干扰强度的集体林、不同权属森林和不同土地利用类型土壤微生物数量及某些生化特性。结果表明,在高黎贡山上半部,自然林随海拔降低,土壤微生物数量及活性升高。而下半部,集体林随海拔降低,人为干扰强度和频率增加,土壤微生物数量和活性降低;森林权属从国有集体个人,土壤微生物数量及活性降低;森林被纯林替代后,土壤微生物数量及活性迅速降低,但耕作通常更有利于微生物繁殖。高黎贡山中部(海拔2000m左右)的自然植被下土壤微生物含量丰富且活性较高,但海拔高气温低不利于土壤微生物生长繁殖及进行生物化学变化。另一方面,森林植被的过份砍伐和利用也使土壤微生物数量和活性降至较低水平。     

沿海养殖池塘对红树林生态系统影响的时空变化监测与分析

随着沿海人类活动的日益加剧, 其对红树林生态系统健康和可持续发展的影响也逐渐凸显, 实现红树林周边典型人类活动时空动态变化监测对红树林生态系统的保护与修复意义重大。该研究基于Landsat多时相遥感数据和Google Earth Engine平台, 通过面向对象的机器学习方法, 融入水体季节波动信息作为分类特征, 获取了1990、2000、2010和2020年4个不同时期中国沿海红树林分布省区(包括广东、福建、浙江、台湾、广西及海南) 30 m分辨率的养殖池塘空间格局及其变化特征, 并进一步解析养殖池塘对红树林生态系统的影响。研究结果表明: (1)研究区域内4个时间节点的沿海养殖池塘面积总量分别为2 963、5 200、5 377及4 805 km², 呈先增加后减少的趋势, 于2010-2020年间达到峰值。沿海养殖池塘面积变化趋势和达峰时间存在明显区域差异性, 其主要原因是红树林保护政策、养殖池塘规范管理和阶段性经济目标的区域差异化。(2)我国沿海养殖池塘集中分布在21°-24° N区域(广东和广西), 与红树林沿纬度的分布格局呈错峰分布。其中, 红树林与沿海养殖池塘集中分布区(21°-22° N)存在大量养殖池塘堤边生长红树林的特色格局, 此区域内两者交互作用最为紧密, 是探究人类活动对红树林生态系统影响的典型热点地区。(3)养殖池塘侵占红树林是造成红树林损失的最直接原因, 并导致红树林空间分布格局呈现局部破碎化或聚集化的极端发展趋势。该研究通过解析沿海养殖池塘的空间格局, 为精准评估红树林周边典型人类活动变化提供数据支撑, 为进一步监测红树林空间格局动态变化趋势和红树林优先修复区识别提供参考依据。     

More and more generalists: two decades of changes in the European avifauna

Biotic homogenization (BH) is a process whereby some species (losers) are systematically replaced by others (winners). While this process has been related to the effects of anthropogenic activities, whether and how BH is occurring across regions and the role of native species as a driver of BH has hardly been investigated. Here, we examine the trend in the community specialization index (CSI) for 234 native species of breeding birds at 10 111 sites in six European countries from 1990 to 2008. Unlike many BH studies, CSI uses abundance information to estimate the balance between generalist and specialist species in local assemblages. We show that bird communities are more and more composed of native generalist species across regions, revealing a strong, ongoing BH process. Our result suggests a rapid and non-random change in community composition at a continental scale is occurring, most likely driven by anthropogenic activities.     

Realized distribution patterns of crowned lemurs (Eulemur coronatus) within a human-dominated forest fragment in northern Madagascar

Due to the impact of anthropogenic activities on forest extent and integrity across Madagascar, it is increasingly necessary to assess how endangered lemur populations inhabiting human-dominated forest fragments can effectively sustain themselves ecologically. Our research addresses this concern by exploring how the distribution patterns of a small population of crowned lemurs (Eulemur coronatus), occupying a degraded forest fragment at Oronjia Forest New Protected Area in northern Madagascar, are impacted by the availability of key ecological and anthropogenic factors. We hypothesize that the distribution of E. coronatus within the fragment is limited by the availability of critical ecological resources and conditions and the intensity of anthropogenic features and activities. To examine this, we used MaxEnt to develop a species distribution model using presence-only occurrence records and 10 independent background covariates detailing the site's ecological and anthropogenic aspects. The results indicate that the realized distribution patterns of E. coronatus within human-dominated forest fragments are strongly associated with sections of forest that contain sparsely and sporadically distributed resources, such as freshwater and continuous hardwood vegetation. We conclude that the distribution of E. coronatus at Oronjia is shaped by their need to maximize foraging opportunities in a degraded forest landscape where they are subject to both environmental and anthropogenic stressors.     

Longer conserved alpine forests ecosystem exhibits higher stability to climate change on the Tibetan Plateau

Aims Vegetation dynamics are simultaneously regulated by climate change and anthropogenic activities. Since the 1980s, climate has been warming on the Tibetan Plateau (TP) at a rate higher than North Hemisphere average. Anthropogenic activities, including grazing, farming, and urbanization, are also influencing the alpine ecosystem on the TP. Especially, an ensemble of large engineering projects, such as power transported from west to east by State Grid, has been in operation on the TP. While studies disentangling effects of climate and anthropogenic activities interference are still lacking for the forest ecosystems on the TP. The overarching objectives of this study were to separate effects of natural climates and human interferences on forest ecosystem dynamics on the TP.     

宁南半干旱地区农田和草地生态系统能量通量的季节变化

根据2002~2003年宁南山区不同下垫面小气候考察资料,用能量平衡法计算了不同下垫面不同季节的感热、潜热通量。分析结果表明:(1)宁南半干旱地区夏季农田和草地的净辐射峰值可达到700W/m2以上,土壤热通量的值比净辐射小1个量级。同类下垫面净辐射通量日积分值夏季>春季>秋季>冬季。(2)宁南半干旱山区感热输送强度以典型草地的最大,其次是禁牧草地,稀树草地的最小。春季各类下垫面地表热量平衡以感热输送为主。在春、夏、秋季的晴天,感热通量日积分值为正,冬季为负。(3)农田在夏、秋季、冬季水汽输送大于各类草地的,其次是稀树草地的,典型草地向上的水汽输送量是最小的。夏季白天农田β在0.2~0.7,稀树草地β为0.2~1.0,能量输送以潜热为主。禁牧草地β为0.2~9.2,典型草地为1.5~13.1,能量输送以感热为主。(4)宁南半干旱地区宜退耕,发展典型草原,在水分充足的山地背阴坡少量发展稀树草地。