Patch Shape Research Articles

广西黑叶猴栖息地景观格局破碎化分析及其对种群的影响

黑叶猴（Trachypithecus francoisi）是仅分布于喀斯特石山生境的珍稀濒危灵长类动物。由于非法捕杀和人类活动干扰，其种群数量正在急剧减少。同时，随着森林砍伐和土地开垦的加速，其栖息地严重破碎化。因此，了解栖息地破碎化对黑叶猴种群的影响对于保护这一珍稀濒危物种具有重要意义。基于遥感影像、土地利用数据以及黑叶猴种群调查数据，通过Fragstats软件开展广西黑叶猴栖息地景观破碎化分析，并通过相关性和多元逐步回归分析，探讨了景观格局对广西黑叶猴种群数量的影响。结果表明：（1）广西黑叶猴栖息地呈现破碎化严峻、斑块形状复杂化、斑块团聚程度较弱且分散化的现象；栖息地以林地景观占据重要优势，但人为景观的干扰十分强烈；在不同地区中，生境破碎化程度、人为干扰强度以及景观配置均呈现不同的特征，其中扶绥地区人为干扰最为强烈，德保地区的景观块数破碎化程度较为严重，而龙州地区的人为干扰程度最小，其森林景观最为聚集。（2）蔓延度指数、平均斑块分维指数、林地面积、林地斑块大小、裸岩面积和裸岩面积比重等景观指数与黑叶猴种群数量有显著正向关系，Shannon多样性指数则是显著负向关系；而耕地面积、耕地面积占比、居民地面积以及居民地面积占比等具有人为干扰性质的景观指数对黑叶猴种群数量没有显著相关性。（3）多元逐步回归分析表明，林地面积的大小是影响广西黑叶猴种群数量关键因子，其次是平均斑块分维指数。因此，在保护规划工作中应该根据黑叶猴分布区的森林覆盖率、破碎化程度、生境连通度以及景观配置情况进行生态恢复，同时也应结合保护区的实际情况进行调整。;The François' langur (Trachypithecus francoisi) is an endangered primate species that is restricted to habitats characterized by karst topography. Because of illegal hunting and disturbance by human activities, its population decreases dramatically. Moreover, its habitats become severely fragmented as results of the acceleration of deforestation and land reclamation. Therefore, it is important to understand the influence of habitat fragmentation on the François' langur population, which will provide key information for the conservation of this rare and endangered species. In this study, based on remote sensing images, land-use data, and the François' langur population survey data, we conducted landscape fragmentation analysis of the François' langur habitat in Guangxi by Fragstats software. We also explored the influences of landscape pattern on the population of François' langurs in Guangxi by correlation analysis and multiple stepwise regression analysis. The results showed that the landscape pattern of the François' langur habitats in Guangxi presented severe fragmentation, complex patch shapes, weak patch aggregation, and decentralization. The woodland landscape still made an important contribution to the langur habitats, but the anthropogenic landscape interference was very strong. There were different characteristics in the degree of habitat fragmentation, the intensity of human disturbance, and the distribution of landscapes in different areas. The Fusui area had the strongest human disturbance, and the Debao area had a more severe degree of fragmentation, while the Longzhou area had the least anthropogenic disturbance and its forest landscape was the most aggregated. There were significantly and positively relationships between Contagion Index, Mean Patch Fractal Dimension, Woodland Area, Woodland Patch Size, Bare Rock Area and Bare Rock Percentage of Landscape and the population of François' langurs, whereas Shannon Diversity Index was significantly and negatively related to the population of François' langurs. However, there was no significant correlation between artificial landscape indices, such as Curtivated Land Area, Percentage of Curtivated Land Residential Land Area, Percentage of Residential Land Area and the population of the François' langur. Based on the results of the multiple stepwise regression analysis, Woodland Area was key factors influencing the population of the François' langur in Guangxi,followed by Mean Patch Fractal Dimension. Therefore, the managers should carry out different types of ecological restoration according to the forest coverage, fragmentation degree, and landscape configuration in the distribution area of the François' langur. At the same time, managers should develop a reliable conservation plan based on the actual situation of the nature reserve.

北京市景观格局演变及其对多种生态系统服务的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 北京市景观格局演变及其对多种生态系统服务的影响 DOI: 10.5846/stxb202107272042 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 城市与区域生态国家重点实验室开放基金项目（SKLURE2020-2-1）；国家自然科学基金青年科学基金项目（41901227） Changes of landscape pattern and its impacts on multiple ecosystem services in Beijing 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:景观格局是人与自然共同作用的结果，深刻影响着区域的生态系统服务及可持续发展。以高度城市化地区——北京市为案例，选取了粮食生产、水质净化、空气净化、气体调节、生境质量以及休闲娱乐6项重要生态系统服务，采用InVEST （Integrated Valuation of Ecosystem Services and Tradeoffs）、ROS （Recreation Opportunity Spectrum）等模型定量评估了1980-2018年生态系统服务时空分布。通过对北京市景观组成与景观配置指数进行定量分析，进一步探索了景观格局演变对生态系统服务的影响。结果表明：（1）北京市1980-2018年建设用地扩张了120%，建设用地扩张是耕地面积减少的主要原因。景观格局总体上趋于破碎化，斑块形状复杂化，斑块异质性增加；（2）时间上，北京市1980-2018年粮食生产、水质净化、气体调节、生境质量、休闲娱乐5项生态系统服务均呈现下降趋势；空间上，粮食生产呈现东南部较高，西北部较低的分布特征，其余生态系统服务均呈现西北部较高，东南部较低，市中心最低的分布特征；（3）景观水平上，林地、建设用地等景观组成变化对生态系统服务影响最为显著。破碎化指数、多样性指数等景观配置指数对生态系统服务影响最为显著；类型水平上，平均斑块面积、斑块聚集度对生态系统服务影响相对最为显著。总体来讲，通过分析景观格局演变如何影响生态系统服务，为如何通过设计和优化景观格局来提升生态系统服务提供了定量依据，从而为促进区域的景观可持续规划提供理论依据和案例参考。 Abstract:Landscape pattern is the result of the interaction between human and nature. During the urbanization process, the landscape pattern had changed significantly, which affected the ecological process and thus threatened ecosystem services. The assessment of the impacts of landscape pattern on ecosystem services is crucial for regional sustainable development. Taking Beijing as a case study, we quantified the spatiotemporal changes of six selected ecosystem services, including food production, water purification, air quality regulation, carbon storage, habitat quality, and recreation opportunity from 1980 to 2018 by using the InVEST and Recreation Opportunity Spectrum (ROS) models. In addition, we analyzed changes of landscape patterns in Beijing, and explored the impacts of landscape patterns on ecosystem services. The results showed that:1) the landscape pattern in Beijing experienced dramatically changes from 1980 to 2018. The build-up land expanded by 120%, which mainly resulted in the reduction of cropland. The overall landscape pattern tended to be fragmented, the patch shape index became more complicated and the heterogeneity of the patches also increased. 2) Food production, water purification, carbon storage, habitat quality, and recreation opportunity showed a decreasing trend from 1980 to 2018. Spatially, food production was higher in the southeast and lower in the northwest. For the other ecosystem services, they were higher in the northwest, lower in the southeast, and the lowest in the central downtown area. During the past 38 years, the food production decreased the most in the central region of Beijing, while the air quality regulation, carbon storage, habitat quality, and recreational opportunity decreased the most in the eastern and southern regions. 3) At the landscape level, changes in land-use types, such as woodland, grassland, and build-up land had the most significant impacts on ecosystem services. Landscape metrics, such as the fragmentation index and diversity index influenced ecosystem services more obviously. At the class level, the mean patch area and the patch aggregation index had the most significant impacts on ecosystem services. Among them, the mean patch area and aggregation index of woodland showed positive effects on air quality and carbon storage. However, the aggregation index of built-up land showed a negative effect on habitat quality. In general, this study focused on analyzing the impacts of landscape pattern changes on ecosystem services, which can help decision makers to improve the ecosystem services by optimizing landscape patterns. The results of this study also can provide theoretical and practical basis for promoting regional landscape sustainable planning. 参考文献 相似文献 引证文献

牲畜排泄物返还对草地土壤氮转化和氧化亚氮(N2O)排放的影响研究进展

牲畜排泄物返还被认为是对草地的一种天然的施肥措施，也是草地养分归还的一种重要途径，对于维持土壤肥力和植被生产力具有十分重要的生态学意义。论述了放牧牲畜粪便和尿液自身降解及其氮素变化、粪尿返还对草地土壤氮转化和氧化亚氮（N₂O）排放的作用机制及影响效应，指出排泄物氮输入使粪尿斑块成为草地土壤氮转化和N₂O排放的活跃点，且不同排泄物类型、土壤理化特性和气候条件等使土壤氮素矿化、固持、硝化及反硝化等关键过程具有复杂性和差异性，进而导致不同类型草地生态系统N₂O排放对牲畜排泄物返还的响应不尽相同。建议未来在全球气候变化背景下，应加强草地牲畜排泄物-植被-土壤体系氮素生物地球化学循环过程的系统研究，进一步加深天然草地关键氮素转化过程和N₂O排放的微生物作用机制方面的认识，从而有助于为优化放牧牲畜排泄物的管理模式、制定科学合理的草地土壤养分调控策略和维持草地生态系统可持续发展提供科学有效的理论指导。;Livestock excreta deposition is considered as a natural fertilization measure in grassland and also an important pathway for the return of grassland nutrients, which may generate greatly ecological significance for the maintenance of soil fertility and vegetation productivity. In this study, we systematically elaborated the variation of nitrogen embedded within grazing livestock dung and urine patches during its natural decomposition, so as to investigate the possible functional mechanisms and influential effects of livestock dung and urine application on soil nitrogen transformation process and nitrous oxide (N₂O) emission. Results showed that livestock excreta nitrogen input made the grassland area covered by dung and urine to become an active point for soil nitrogen transformation and N₂O emission. Generally speaking, the degradation rate of livestock dung was slow and its nitrogen release usually lasts for a long time, which may generate a series of effects on the soil nitrogen transformation and N₂O emission in the natural grassland. On the contrary, livestock urine deposition would rapidly increase soil mineralized nitrogen content in a short period of time, thus may generate a certain of priming effect on nitrogen dynamic and its form transformation in soil profiles, which probably deeply change the soil available nitrogen contents and the microenvironment that related to N₂O emission. It is worth noting that the differences in dung and urine patch shape, physicochemical properties, degradation and nitrogen release characteristics would inevitably alter the soil redox condition, nitrogen content and its form features of grassland soil profiles in different degrees, which may cause the complicated temporal-spatial response of soil nitrogen migration and transformation processes and the microbial functional mechanism differences in N₂O generation and emission. In addition, the differences in excreta types, soil physicochemical properties, and climatic conditions would complicatedly influence the major processes of soil nitrogen mineralization, immobilization, nitrification and denitrification, and therefore resulted in differential response of N₂O emission in different grassland ecosystems. Scientific suggestions were put forward that more attentions should be paid to strengthening the systematic research on the nitrogen biogeochemical cycling in the faecal-vegetation-soil system of grassland under the background of climate change, in order to deeply improve the theoretical understanding of major nitrogen transformation process and microbial mechanism of N₂O production and emission in the natural grassland. The results would provide scientific and theoretical guidance for optimizing livestock excreta management models, and formulating reasonable regulation strategies of grassland soil nutrients, so as to maintain the sustainable development of grassland ecosystems.

Design and Analysis of Single Layer Proximity Fed Sierpinski Fractal 2x1 Array Antenna Embedded on Hexagon Shaped Patch with Defected Ground Structure

A novel innovative technique for producing a single layer proximity fed triple band antenna based on second iteration level Sierpinski fractal geometry implanted on a hexagonal shaped array antenna is being presented for next-generation cellular networks. The steps of fractal array antenna growth are examined. The array antenna is supplied using a single layer proximity fed method. The suggested single layer proximity fed hexagonal shaped array antenna with defective ground structure is developed and simulated using CST Microwave Studio, and characteristics such as bandwidth, return loss, directivity, and radiation pattern are investigated. The second iteration level single layer proximity fed array antenna's simulated -10 dB impedance bandwidth for the lower band is 237 MHz (1.6480 – 1.8850 GHz) with peak resonance at 1.8010 GHz, the middle band bandwidth is 66 MHz (2.4280 – 2.4940 GHz) with peak resonance at 2.4640 GHz, and the upper band bandwidth is 69 MHz (2.9080 – 2.9778 GHz) with peak resonance at 2.9 This antenna may be used for a wide range of wireless communication applications.

Design of Tri Band and Dual Band Antenna Using Meta Cell

A 15 × 20 × 1.6 mm3 a novel T shape patch Antenna inspired by unit cell is investigated by changing position of meta cell. The proposed antennas have dual band (3.53-5.3GHz) and tri band (3.1-3.2GHz, 4.9-5.56GHz, 6.22-6.76GHz) nature operating at S, C band Applications .Here we observed the designed antenna has S11 < −10 dB and gain was positive at operating bands.

Fragmentation Trajectories as a Review of Existing and Proposed Single-valued Fragmentation Indices

Two related single-valued landscape fragmentation indices D and F are proposed, based on patch aggregation, shape complexity, and percent of the focal pixels on the landscape, and are computed using Fragstats metrics on a colonization landscape continuously fragmented over 36 years. The same was done for two existing single-valued fragmentation indices, i.e., the Matheron index based solely on normalized unlike joins, and the Normalized Hypsometric Curve (NHMC) index from GUIDOS Toolbox. All were plotted chronologically, and also against percent non-forest (%nf) of the landscape, and the trajectories were compared for behavior. The NHMC index starts high even if deforestation is low, and continues increasing even further as deforestation continues, while the other three indices all start close to zero and increase gradually. F mimics D very closely, and the Matheron index only behaves differently from F and D at the end of the data range. The deviation may be due to patch aggregation, which the Matheron index does not consider. An accepted single-valued fragmentation index computed from Fragstats landscape metrices could allow for cross-study comparisons relating fragmentation with any other attribute on or of the landscape, hopefully advancing the science of fragmentation in landscape ecology as cross-study generalizations would now be possible.

ANALYSIS OF SPATIO-TEMPORAL URBAN DYNAMICS IN 11 SMART CITIES OF UTTAR PRADESH, INDIA

Abstract. Urban planning in smart cities needs to be done in a “Smart” way. One way is to analyze the urbanisation pattern by spatio-temporal change detection techniques. Classified data such as, for years 1985, 1995 and 2005 Decadal Land use data for India and for year 2015, Copernicus Global Land service Dynamic Land Cover layers (CGLS-LC100 products) are used to perform multi-temporal analysis of the 11 smart cities of Uttar Pradesh state of India namely "Agra", "Aligarh", "Bareilly", "Jhansi", "Kanpur", "Lucknow", "Moradabad", "Prayagraj", "Rampur", "Saharanpur" and "Varanasi". Dynamics of Urban expansion are studied utilizing concepts of Landscape Metrics calculated by FRAGSTATS and also Shannon’s Entropy Values (Hn) over the 11 smart cities. Largest Patch Index (LPI), Landscape Shape Index (LSI), Aggregation Index (AI) and Mean Euclidean Nearest Neighbor Distance (ENN_MN) are metrics used to characterize urbanisation. Results indicate rise in value of LSI over the years from 1985 and with sudden increase in year 2015 for Built-up patches, corroborating more complexity in shapes of Built-up patches in all 11 cities. Kanpur, showing large values of LPI indicates the sudden increase of Built-up land use class over the years. The decreasing value of ENN_MN over the years indicates less centrality for built-up pixels in urbanisation. AI is unchanged for Built-up patches for 1985–1995 but decrease in year 2015 indicates less compactness which is due to dispersion of built-up pixels. High values of Hn over the years indicating dispersion of urbanisation in all 11 smart cities except Agra, also validates results.

Application of spatial- and diachronic-process analysis of landscape development in Central Lika, Croatia from 1980 to 2012

The paper presents structural features and the process and intensity of landscape changes in the Central Lika Region of Croatia, in the transitional, post-socialist and post-war periods (1980–2012). The aim of this paper is to analyse regularities and interrelations between the changes in structural features and the intensity of the processes that cause change. By using GIS spatial analysis methods, the shape, position, and condition of landscape patches were defined for each year. The diachronic process analysis, with the application of a specially-developed index — the Landscape Development Index (di) — made it possible to determine the intensity of development of individual landscape elements. The landscape was observed using the concept of Land Use/Land Cover (LULC) and, for this purpose, data from the CORINE Land Cover database were used for 1980 and 2012. The results showed fragmentation and an increase in the number and complexity of patches, as well as a decrease of the core patch area. Consequently, the increase of the share of edge areas has increased vulnerability to external influences and changes. Applying the Landscape Development Index (di) showed advantages compared to a standard comparison of the two conditions or synthetic indices, enabling the intensity of each observed phenomenon/process to be determined, and allowing for deeper spatial and temporal analysis as well as better understanding of landscape development.

Landscape structure and local variables affect plant community diversity and structure in a Brazilian agricultural landscape

AbstractThe biodiversity in agricultural landscapes depends on land‐use types, natural elements, and farming intensity. The Brazilian Cerrado is a biodiversity hotspot, however, the native vegetation loss rates have increased in the last years, leading several plant species to extinction risk. Here, we analyze the effects of local (soil fertility and litter amount) and landscape variables (patch shape, habitat amount, compositional heterogeneity, matrix dominance and connectivity) on alpha species richness and diversity, and basal area of different Cerrado vegetation types (savanna, forested savanna, and forest) using linear models and Akaike information criterion. We calculated landscape metrics at different spatial scales for 49 sampling sites in intensive farming landscapes. Woody plant diversity and richness were positively related to soil fertility and landscape compositional heterogeneity at 1500 m spatial scale. Plant richness was negatively related to the patch shape of remnants at 1000 m spatial scale. The effects of litter amount to explain the basal area varied between vegetation types. We found a positive effect in savanna and forested savanna and a negative effect in forest areas. Our findings suggest that the increase of monocultures lead to a decline on plant diversity in the studied landscapes. Also, local variables and the diversity of vegetation types need to be considered to design restoration actions in Cerrado. Sustainable intensification and biodiversity‐friendly production systems may be alternatives to increase compositional heterogeneity, thus favoring plant diversity in Cerrado farming landscapes.Abstract in Portuguese is available with online material.

Geometrical Investigation of Piezoelectric Patches for Broadband Energy Harvesting in Non-Deterministic Composite Plates.

Mechanical energy is the most ubiquitous form of energy that can be harvested and converted into useful electrical power. For this reason, the piezoelectric energy harvesters (PEHs), with their inherent electromechanical coupling and high-power density, have been widely incorporated in many applications to generate power from ambient mechanical vibrations. However, one of the main challenges to the wider adoption of PEHs is how to optimize their design for maximum energy harvesting. In this paper, an investigation was conducted on the energy harvesting from seven piezoelectric patch shapes (differing in the number of edges) when attached to a non-deterministic laminated composite (single/double lamina) plate subjected to change in fiber orientation. The performance of the PEHs was examined through a coupled-field finite element (FE) model. The plate was simply supported, and its dynamics were randomized by attaching randomly distributed point masses on the plate surface in addition to applying randomly located time-harmonic point forces. The randomization of point masses and point force location on a thin plate produce non-deterministic response. The design optimization was performed by employing the ensemble-responses of the electrical potential developed across the electrodes of the piezoelectric patches. The results present the optimal fiber orientation and patch shape for maximum energy harvesting in the case of single and double lamina composite plates. The results show that the performance is optimal at 0° or 90° fiber orientation for single-lamina, and at 0°/0° and 0°/90° fiber orientations for double-lamina composites. For frequencies below 25 Hz, patches with a low number of edges exhibited a higher harvesting performance (triangular for single-lamina/quadrilateral for double-lamina). As for the broadband frequencies (above 25 Hz), the performance was optimal for the patches with a higher number of edges (dodecagonal for single-lamina/octagonal for double-lamina).

Coordination Conflicts between Urban Resilience and Urban Land Evolution in Chinese Hilly City of Mianyang

Urban resilience, the combinational characteristic of nature and society, that reflects the dynamic accumulation process that is multi-level and multi-dimensional. Particularly, the rational spatial distribution structure of land mixture and compactness is an effective way to improve urban resilience because the evolution of morphology and density of the urban land blocks in the process of land spatial conversion reflect the performance characteristics of complexity, diversity, stability, compactness, and connectivity. Therefore, we evaluated the relationship between urban resilience and land use and land cover (LULC) change, to find the keys to resilient urban development for urban land and space planning. In this study, taking the Chinese hilly city of Mianyang as an example, the results show: (1) the complexity of homogeneous patch shape and heterogeneous patch combination leads to the decrease of urban morphology resilience. (2) the development trend of LULC spatial layout and structure ratio were more rational with the increased of land mixing degree. (3) the speed and intensity of urban expansion were basically coordinated with the development of urban resilience. The research provides the new ideas, approaches, and toolkits for solving the intractable problems of urban spatial planning based on coordinating conflicts between urban resilience and urban land evolution.

Design of Compact MIMO Multiband Antenna for Wireless Radio Communication Application

Slot and patch modification for the design of a compact multiband antenna with Multi-Input-Multi-Output (MIMO) functionality is proposed in this paper. At various frequency bands, the antenna performance is obtained by modification and addition of slot and patch shapes in the design of the compact MIMO multiband antenna. Addition of slots or patches is done separately in the already existing multiband antenna designs. Whereas in this work, the addition of slot and patch are combined. Arlon Diclad 880 with a dielectric constant of 2.17 - 2.2 (εr) and height 0.75mm is used for the antenna design. The MIMO multiband antenna with the dimension of 12.5 mm × 7.5 mm is designed. On various millimeter-wave frequency bands ranging from 20 GHz to 40 GHz, the MIMO antenna can function as observed in the results of simulation and evaluation. This work shows that microstrip antennas can be added with slots and patches during their design and development, thereby enabling the antenna to operate under multiple frequency bands.

Fragmented landscapes affect honey bee colony strength at diverse spatial scales in agroecological landscapes in Kenya.

Landscape fragmentation and habitat loss at multiple scales directly affect species abundance, diversity, and productivity. There is a paucity of information about the effect of the landscape structure and diversity on honey bee colony strength in Africa. Here, we present new insights into the relationship between landscape metrics such as patch size, shape, connectivity, composition, and configuration and honey bee (Apis mellifera) colony strength characteristics. Remote-sensing-based landscape variables were linked to honey bee colony strength variables in a typical highly fragmented smallholder agroecological region in Kenya. We examined colonies in six sites with varying degrees of land degradation during the period from 2017 to 2018. Landscape structure was first mapped using medium resolution bitemporal Sentinel-1 and Sentinel-2 satellite imagery with an optimized random forest model. The influence of the surrounding landscape matrix was then constrained to two buffer distances, i.e., 1 km representing the local foraging scale and 2.5 km representing the wider foraging scale around each investigated apiary and for each of the six sites. The results of zero-inflated negative binomial regression with mixed effects showed that lower complexity of patch geometries represented by fractal dimension and reduced proportions of croplands were most influential at local foraging scales (1 km) from the apiary. In addition, higher proportions of woody vegetation and hedges resulted in higher colony strength at longer distances from the apiary (2.5 km). Honey bees in moderately degraded landscapes demonstrated the most consistently strong colonies throughout the study period. Efforts towards improving beekeeper livelihoods, through higher hive productivity, should target moderately degraded and heterogeneous landscapes, which provide forage from diverse land covers.

Landscape and microhabitat features determine small mammal abundance in forest patches in agricultural landscapes.

Intensification of agricultural landscapes represent a major threat for biodiversity conservation also affecting several ecosystem services. The natural and semi-natural remnants, available in the agricultural matrix, represent important sites for small mammals and rodents, which are fundamental for sustaining various ecosystem functions and trophic chains. We studied the populations of two small mammals (Apodemus agrarius, A. sylvaticus) to evaluate the effects of landscape and habitat features on species abundance along a gradient of agricultural landscape intensification. The study was performed in Friuli Venezia Giulia (north-eastern Italy) during 19 months, in 19 wood remnants. Species abundance was determined using Capture-Mark-Recapture (CMR) techniques. In the same plots, main ecological parameters of the habitat (at microhabitat and patch scale) and landscape were considered. Abundance of A. agrarius increased in landscapes with high extent of permanent crops (i.e., orchards and poplar plantations) and low content of undecomposed litter in the wood understory. Instead, A. sylvaticus, a more generalist species, showed an opposite, albeit less strong, relationship with the same variables. Both species were not affected by any landscape structural feature (e.g., patch shape, isolation). Our findings showed that microhabitat features and landscape composition rather than wood and landscape structure affect populations’ abundance and species interaction. The opposite response of the two study species was probably because of their specific ecological requirements. In this light, conservation management of agricultural landscapes should consider the ecological needs of species at both landscape and habitat levels, by rebalancing composition patterns in the context of ecological intensification, and promoting a sustainable forest patch management.

Numerical Analysis of the Bonded Composite Shape Effects under Thermal Loading in Aircraft Structures

The design of the optimal shape of patch with a good compromise between mechanical performances and manufacturing aspects can be sought in order to get the maximum structural safety-cost ratio. In this work an analysis has been conducted for development of a finite element methodology to circumvent the thermal effect problem in the bonded repair. Physical and geometrical parameters of the repair material were assumed to be variables, this method are based on two approaches: The first, have modified the patch shape by removing the two isosceles notches (h varied) for minimisation the heating size in the direction of loading. For the second step of the study, the same surface previously deduced are compensate in the other direction with varied the property module for the adhesive layer, for inducing a larger the area covering of crack tip and reduce the thermal stress. The values of thermal stresses obtained from the variation of these two parameters were found to be low compared to the obtained values for initial shape.

Metamaterial Based Multiband Microstrip Patch Antenna for 5G Wireless Technology-enabled IoT Devices and its applications

In the present era of the digital world, demand for IoT based smart devices has seen tremendous growth. These devices involve real-time human-to-machine communication and interaction. Communication of uninterrupted quality depends on the high bandwidth and speed of the internet. The development of 5G wireless network technology is the response to the crucial factors that lead to this demand, because of its ability to provide extremely fast internet speed, high bandwidth, high performance, reduced latency, and high reliability. In this research work, the authors have developed a metamaterial-based multi-band microstrip rectangular shape patch antenna with a wide high-performance bandwidth because of the demand. The proposed design has a low dielectric constant of 2.2, which is of Rogers RT/Duroid substrate, and a dielectric loss tangent of 0.0010. The design has a resonant frequency of 26 GHz. The simulations carried out using FEKO software has been analyzed for performance. The simulation and analysis reveal a good return loss of -34.4 dB at 26 GHz, -13.49 dB at 40 GHz, -13.63 dB at 53.5 GHz, high bandwidth of 5.368 GHz at 26 GHz, 3.76 GHz at 40 GHz, 2.88 GHz at 53.5 GHz, desirable voltage standing wave ratio, 1⩽VSWR⩽ 2, high gain of 10 dBi at 26 GHz, 5 dBi at 40 GHz, and high antenna radiation efficiency of 99.7 % at 26 GHz, and 61% at 40 GHz, 50% at 53.5 GHz. The bandwidth, return loss, antenna radiation efficiency and power density indicate an improvement of 5.368 GHz to 5.630 GHz, -34.82 dB to -57.10 dB, 99.7 % to 99.8 % and 2208 kW/m2 to 2800 kW/m2 respectively after loading and incorporating artificial magnetic split-ring resonator-based metamaterial on the patch. Further improvement is also seen at other frequencies. The proposed design has immense benefits for humanity due to its improved capacity to manage larger connected IoT devices in the fields of Industrial 4.0, Healthcare 4.0, Autonomous Vehicles, Agriculture 4.0, Education, Climate Change, Sustainability, and Oceanography.

Analysis of the urban growth pattern through spatial metrics; Ankara City

Analysis of the urban growth pattern through spatial metrics; Ankara City

The Ecosystem Services Value Change and Its Driving Forces Responding to Spatio-Temporal Process of Landscape Pattern in the Co-Urbanized Area

The development of urbanization is still expanding on the earth, and the rapid expansion of cities has changed the regional landscape pattern and significantly affected the value of regional ecosystem services in developing countries such as China. Zhongmu County, as the core area of Zhengzhou-Kaifeng integration, studying the temporal and spatial transformations of its landscape pattern and ecosystem service value (ESV) is of great significance to the region’s sustainable development. Based on remote sensing images and socioeconomic data, this study aims to explore the landscape pattern of Zhongmu County from 2005 to 2018 and its impact on ESV. Research methods include an ESV equivalent factor method, landscape pattern index, spatial autocorrelation, and other methods. The results showed that: (1) During the study period, the patch density and shape complexity, landscape diversity, and fragmentation of the overall landscape in the study area continued to increase while landscape connectivity decreased. (2) The total amount of ESV increased by 10.05 million USD; ESV had certain differences in spatial distribution: high-value clusters were mainly located at the boundary of the Yellow River in the north, while low-value clusters had a significant eastward expansion trend. (3) ESV increased significantly in areas where cultivated land was transferred to waters and forests, and ESV in areas where waters transferred to construction land and cultivated land was significantly reduced. (4) ESV had a significant positive spatial correlation with patch density, edge density, mean patch fractal dimension, mean patch size, and the landscape shape index, and a spatially negative correlation with the contagion index and cohesion index. The spatial and temporal changes in landscape patterns and ESV were all mainly driven by the regional development “Zhengzhou-Kaifeng integration” policy. Therefore, the ESV can be improved, and the ecological security of the urban integration area can be guaranteed through policy measures such as optimizing the layout of construction land and adjusting the uniform distribution of green areas by the land-use policy.

A Pseudo‐Lagrangian Transformation to Study a Chlorophyll‐a Patch in the Ría de Vigo (NW Iberian Peninsula)

AbstractBecause of the difficulties in tracking a water mass over time and conducting synoptic surveys over large spatial scales, measurements of biological variables in the ocean are often restricted to isolated Eulerian observations. Here a proof‐of‐concept of a pseudo‐Lagrangian transformation was applied to a time series of chlorophyll‐a profiles acquired at a single fixed station to diagnose the shape of a phytoplankton patch, and its physical‐biological rates of transformation. During August 2013, a 27‐hr time series of observations of horizontal currents, hydrographic properties, turbulent mixing and chlorophyll‐a was acquired at a central station of the Ría de Vigo (NW Iberian Peninsula). A chlorophyll‐a patch, tilted upward toward the inner part of the Ría, was observed moving back and forth past the sampling station. Its shape and position during the sampling period were modulated by the semi‐diurnal (M2) tidal currents and the vertically sheared upwelling circulation. The pseudo‐Lagrangian transformation allowed estimation of chlorophyll‐a net rates of change. These rates were positive between 12 and 14 m depth, and negative elsewhere, with a mean value of −0.001 ± 0.449 days−1 within the patch maximum. After accounting for the effects of diffusion and sinking, the mean net biological production rate in the upper 15 m (0.53 ± 0.25 days−1) was comparable with in vitro estimates of the balance between phytoplankton growth and mortality obtained from dilution experiments carried out under similar conditions (0.2 ± 0.7 days−1). This pseudo‐Lagrangian transformation is complementary to traditional analyses for the quantification of ecological processes and biogeochemical budgets.

Effects of Urbanization on Landscape Patterns in the Middle Reaches of the Yangtze River Region

The middle reaches of the Yangtze River region (MRYRR) are China’s first trans-regional urban agglomeration, located in the center of the Yangtze River Economic Belt. The MRYRR is an important ecological reserve, and its land cover changes are affected by both socio-economic development and geographical environment. In this paper, Landsat ETM/TM/OLI remote sensing images were used to monitor land use and landscape patterns from 1990 to 2015. Through supervised classification, land use transfer matrix, landscape pattern metrics and correlation analysis, the spatial-temporal patterns of land use change and its relationship with socio-economic in the study area were revealed. The results showed that: (1) the main land use types in the study area were cropland (CL) and forestland (FL), accounting for more than three-quarters of the study area. During the study period, built-up land (BL) increased, CL decreased, FL increased first and then decreased; (2) the BL expanded mainly by occupying CL and FL, and regional landscape pattern was gradually fragmented, with complex patch shape and increasing diversity and heterogeneity. Among them, the BL is gradually gathered, and the FL and CL are gradually fragmented; (3) in the past 25 years, the urbanization process in this region has been obvious, and the Gross Domestic Product (GDP) has increased by 36 times. The socioeconomic variables were positively correlated with BL, orchard (OL) and Shannon diversity index (SHID), and negatively correlated with CL, Wasteland (WL), mean patch size (MPS) and contagion size (CONTAG). The results showed that the urbanization development has a great impact on the region, and the ecological protection task is still challenging. It is necessary to protect high-quality cropland and draw a red line for ecological protection. We should strengthen the construction of ecological corridors and ecological nodes to adapt to regional sustainable development.