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Comparison of satellite images with different spatial resolutions to estimate stand Structural diversity in urban forests

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Journal of Forestry Research 2017年第4期28卷 805-814页

作者： Ulas Yunus Ozkan Ibrahim Ozdemir Tufan Demirel Serhun Saglam Ahmet Yesil Department of Forest Management Faculty of ForestryIstanbul University Wildlife Ecology and Management Faculty of ForestrySuleyman Demirel University

The Structural diversity in urban forests is highly important to protect biodiversity. In particular, fruit trees and bush species, cavity-bearing trees and coarse, woody debris provide habitats for animals to feed, nest and hide. Improper silvicultural practices, intensive recreational use and illegal harvesting lead to a decline in the Structural diversity in forests within larger metropolitan cities. It is important to monitor the Structural diversity at definite time intervals using effective technologies with a view to instituting the necessary conservation measures. The use of satellite images seems to be appropriate to this end. Here we aimed to identify the associations between the textural features derived from the satellite images with different spatial resolutions and the Structural diversity indices in urban forest stands (Shannon-Wiener index, complexity index, dominance index and density of wildlife trees). RapidEye images with a spatial resolution of 5?m × 5?m, ASTER images with a spatial resolution of 15?m × 15?m and Landsat-8 ETM satellite images with a spatial resolution of 30?m × 30?m were used in this study. The first-order (standard deviation of gray levels) and second order (GLCM entropy, GLCM contrast and GLCM correlation) textural features were calculated from the satellite images. When associations between textural features in the images and the Structural diversity indices were assessed using the Pearson correlation coefficient, very high associations were found between the image textural features and the diversity indices. The highest association was found between the standard deviation of gray levels (SDGLRAP) derived from RVIRAP of RapidEye image and the Shannon-Wiener index (H h) calculated on the basis of tree height (R 2?=?0.64). The findings revealed that RapidEye satellite images with a spatial resolution of 5?m × 5?m are most suitable for estimating the Structural diversity in urban forests.

关键词： Biodiversity Satellite image Structural diversity Texture measures Urban forests

Quantifying forest Structural diversity based on large-scale inventory data:a new approach to support biodiversity monitoring

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Forest Ecosystems 2018年第4期5卷 472-485页

作者： Felix Storch Carsten F.Dormann Jurgen Bauhus Chair of Silviculture Tennenbacherstr 4University of FreiburgD-79085 FreiburgGermany Chair of Biometry Tennenbacherstr.4University of FrelburgD-79085FreiburgGermany

Background: The importance of structurally diverse forests for the conservation of biodiversity and provision of a wide range of ecosystem services has been widely recognised. However, tools to quantify Structural diversity of forests in an objective and quantitative way across many forest types and sites are still needed, for example to support biodiversity monitoring. The existing approaches to quantify forest Structural diversity are based on small geographical regions or single forest types, typically using only small data sets.Results: Here we developed an index of Structural diversity based on National Forest Inventory(NFI) data of BadenWurttemberg, Germany, a state with 1.3 million ha of diverse forest types in different ownerships. Based on a literature review, 11 aspects of Structural diversity were identified a priori as crucially important to describe Structural diversity. An initial comprehensive list of 52 variables derived from National Forest Inventory(NFI) data related to Structural diversity was reduced by applying five selection criteria to arrive at one variable for each aspect of Structural diversity. These variables comprise 1) quadratic mean diameter at breast height(DBH), 2) standard deviation of DBH, 3) standard deviation of stand height, 4) number of decay classes, 5) bark-diversity index, 6) trees with DBH ≥ 40 cm, 7) diversity of flowering and fructification, 8) average mean diameter of downed deadwood, 9) mean DBH of standing deadwood, 10) tree species richness and 11) tree species richness in the regeneration layer. These variables were combined into a simple,additive index to quantify the level of Structural diversity, which assumes values between 0 and 1. We applied this index in an exemplary way to broad forest categories and ownerships to assess its feasibility to analyse Structural diversity in large-scale forest inventories.Conclusions: The forest structure index presented here can be derived in a similar way from standard inventory variables for most other large-scale forest in

关键词： Stand structure Structural diversity Structural diversity index Large-scale forest inventory Angle count sampling

In silico Analysis of Sequential,structural and Functional diversity of Wheat Cystatins and Its Implication in Plant Defense

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Genomics, Proteomics & Bioinformatics 2010年第1期8卷 42-56页

作者： Shriparna Dutt V.K. Singh Soma S.Marla Anil Kumar Department of Molecular Biology and Genetic Engineering G.B.Pant University of Agriculture and Technology

Phytocystatins constitute a multigene family that regulates the activity of endogenous and/or exogenous cysteine proteinases. Cereal crops like wheat are continuously threatened by a multitude of pathogens, therefore cystatins offer to play a pivotal role in deciding the plant response. In order to study the need of having diverse specificities and activities of various cystatins, we conducted comparative analysis of six wheat cystatins （WCs） with twelve rice, seven barley, one sorghum and ten corn cystatin sequences employing different bioinformatics tools. The obtained results identified highly conserved signature sequences in all the cystatins considered. Several other motifs were also identified, based on which the sequences could be categorized into groups in congruence with the phylogenetic clustering. Homology modeling of WCs revealed 3D structural topology so well shared by other cystatins. Protein-protein interaction of WCs with papain supported the notion that functional diversity is a con- sequence of existing differences in amino acid residues in highly conserved as well as relatively less conserved motifs. Thus there is a significant conservation at the sequential and structural levels; however, concomitant variations maintain the functional diversity in this protein family, which constantly modulates itself to reciprocate the diversity while counteracting the cysteine proteinases.

关键词： wheat cystatins Structural diversity functional diversity comparative analysis

Synthesis and Structural diversity of alkali-metal(Li,Na,K) alkyl magnesiates containing bidentate aminopyrrolyl ligand

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Synthesis and structural diversity of alkali-metal(Li,Na,K) ...

Recent advances of mixed-transition-metal-substituted polyoxometalates

中国化学会第八届全国配位化学会议

作者： Zhiqiang Guo Xiaoqin Wu Xuehong Wei Scientific Instrument Center Shanxi University School of Chemistry and Chemical Engineering Shanxi University

The advantages of bimetallic "ate" complexes have over conventional alkali metal reagents(use of milder reaction conditions,better functional group tolerance,access to hitherto inaccessible synthetic chemistry,etc.) ensure that this area of research will blossom further in the coming years[1].Most of these studies have focused on main-group metal systems,which combine an alkalimetal with a more electronegative metal such as Mg,Zn(pseudo main group because of its s→s reactivity),or Al[2].As a part of our ongoing interest in the development of new reaction systems based on bimetallic compounds supported by multidentate pyrrole-based ligands[3],herein we have focused on the versatile bonding modes of bidentate dianionic pyrrolyl ligand[C H NH(2-CH NHBu)]as model proligand,And demonstrated three alkalimetal(Li,Na) alkyl magnesiates with a variety of intriguing structures.These new types of alkali-metal alkyl magnesiates shed a new light on pyrrolyl-based complexes and could provide useful tools in the field of bimetallic cooperativity.

关键词： Synthesis Structural diversity Alkali-metal magnesiates Aminopyrrole

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Science China Chemistry 2022年第8期65卷 1515-1525页

作者： Zhimin Wang Xing Xin Mo Zhang Zheng Li Hongjin Lv Guo-Yu Yang MOE Key Laboratory of Cluster Science Beijing Key Laboratory of Photoelectroic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 102488China

Polyoxometalates(POMs)have been emerging as one of the most widely-studied interdisciplinary research fields of inorganic chemistry due to their structural diversities and versatile physicochemical properties.The incorporation of transition metals into lacunary POM ligands can lead to the formation of various transition-metal-substituted POMs(TMSPs)with wide potential applications in research areas including medicine,magnetism,functional materials,catalysis,and energy storage.In this review,we summarized the recent advances of mixed-transition-metal-substituted POMs(Mixed TMSPs)with respect to their synthetic strategies,structural diversities,and relevant applications.Finally,a comprehensive outlook of this research area was also prospected.

关键词： polyoxometalates lacunary POM ligands mixed-transition-metal substitution Structural diversity catalysis

Macrolactins:biological activity and biosynthesis

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Marine Life Science & Technology 2021年第1期3卷 62-68页

作者： Ting Wu Fei Xiao Wenli Li Key Laboratory of Marine Drugs Ministry of Education of ChinaSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology Qingdao 266237China

Marine microorganisms have proven to be a rich source of natural products with unique structures and novel activities,due to their special living conditions.Macrolactins(MLNs),mostly produced by marine-derived microorganisms,are a group of 24-membered lactone natural products,which exhibit potent antibacterial,antifungal,antiviral,anticancer,antiinfammatory,anti-angiogenic and other activities.Their extensive biological activities make them potential compounds for drug development.MLNs are biosynthesized via a type I polyketide synthase(PKS)pathway with diferent tailoring steps,such as epoxidation,glycosylation and acylation.These modifcation steps provide opportunities to diversify their structures by combinatorial biosynthesis strategies.This review mainly focuses on the newly discovered MLNs in the past fve years,including their biological activities and relevant biosynthetic studies.

关键词： Macrolactins Biological activities Biosynthesis Structural diversity

Oximes： Unrecognized Chameleons in Genera and Specialized Plant Metabolism

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Molecular Plant 2018年第1期11卷 95-117页

作者： Mette S rensen Elizabeth H.J. Neilson Birger Lindberg Moiler Plant Biochemistry Laboratory Department of Plant and Environmental Sciences University of Copenhagen Thorvaldsensvej 40 Frederiksberg C Copenhagen Denmark VILLUM Center for Plant Plasticity University of Copenhagen Thorvaldsensvej 40 Frederiksberg C Copenhagen Denmark Center for Synthetic Biology University of Copenhagen Thorvaldsensvej 40 Frederiksberg C Copenhagen Denmark

Oximes （R1R2C=NOH） are nitrogen-containing chemical constituents that are formed in species representing all kingdoms of life. In plants, oximes are positioned at important metabolic bifurcation points between general and specialized metabolism. The majority of plant oximes are amino acid-derived metabolites formed by the action of a cytochrome P450 from the CYP79 family. Auxin, cyanogenic glucosides, glucosinolates, and a number of other bioactive specialized metabolites including volatiles are produced from oximes. Oximes with the E configuration have high biological activity compared with Z-oximes. Oximes or their derivatives have been demonstrated or proposed to play roles in growth regulation, plant defense, pollinator attraction, and plant communication with the surrounding environment. In addition, oxime-derived products may serve as quenchers of reactive oxygen species and storage compounds for reduced nitrogen that may be released on demand by the activation of endogenous turnover pathways. As highly bioactive molecules, chemically synthesized oximes have found versatile uses in many sectors of society, especially in the agro- and medical sectors. This review provides an update on the Structural diversity, occurrence, and biosynthesis of oximes in plants and discusses their role as key players in plant general and specialized metabolism.

关键词： Structural diversity CYP79 auxin cyanogenic glucosides volatile organic compounds E-oxime Z-oxime

Two Co(Ⅱ)-based Coordination Polymers Constructed fromπ-electron-rich Polycarboxylate Aryl Ether Ligand:structural Insights and Photocatalytic Dye Degradation

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Chinese Journal of structural Chemistry 2021年第6期40卷 722-728,683页

作者：王笑峰郭欣雨刘涛 School of Hydraulic and Electric Power Heilongjiang UniversityHarbin 150080China College of Science Northeast Agricultural UniversityHarbin 150038China

In the present study,two new Co(Ⅱ)-based coordination polymers(CPs)with chemical formulas of{[Co_(3)(μ_(3)-OH)(L)(H_(2)O)_(3)]·2H_(2)O}n(1)and{[Co_(3)(μ_(3)-OH)(L)(H_(2)O)]·2DMF·3H_(2)O}n(2)have been successfully prepared by the reaction of Co(NO_(3))_(2)·6H_(2)O withπ-electron-rich polycarboxylate aryl ether ligand 5,5’-((5-carboxy-1,3-phenylene)bis(oxy))diisophthalic acid(H5L)under different solvothermal reaction conditions.Both CPs have been studied via single-crystal X-day diffraction,powder X-ray diffraction(PXRD)and thermogravimetric analysis(TGA).The photophysical studies indicated that complex 2 with good water stability is a potential semiconductive material,which could be applied for the degradation of methylene blue(MB)under UV light irradiation and exhibit good stability and recyclability.

关键词： coordination polymer Structural diversity aryl ether ligand dye degradation

National Forest Inventories capture the multifunctionality of managed forests in Germany

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Forest Ecosystems 2021年第1期8卷 50-68页

作者： Nadja K.Simons María R.Felipe-Lucia Peter Schall Christian Ammer Jürgen Bauhus Nico Blüthgen Steffen Boch François Buscot Markus Fischer Kezia Goldmann Martin M.Gossner Falk Hänsel Kirsten Jung Peter Manning Thomas Nauss Yvonne Oelmann Rodica Pena Andrea Polle Swen C.Renner Michael Schloter Ingo Schöning Ernst-Detlef Schulze Emily F.Solly Elisabeth Sorkau Barbara Stempfhuber Tesfaye Wubet Jörg Müller Sebastian Seibold Wolfgang W.Weisser Terrestrial Ecology Research Group Technische Universität MünchenHans-Carl-von-Carlowitz-Platz 285354 FreisingGermany Present address:Ecological Networks Technische Universität DarmstadtSchnittspahnstraße 364287 DarmstadtGermany Helmholtz Centre for Environmental Research-UFZ Department of Ecosystem ServicesDeutscher Platz 5e04103 LeipzigGermany Present address:German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5e04103 LeipzigGermany Silviculture and Forest Ecology of the Temperate Zones University of GöttingenBüsgenweg 137077 GöttingenGermany Centre for Biodiversity and Sustainable Land-use University of GöttingenBüsgenweg 137073 GöttingenGermany Chair of Silviculture Faculty of Environment and Natural ResourcesUniversity of FreiburgTennenbacherstr.479106 FreiburgGermany Ecological Networks Technische Universität DarmstadtSchnittspahnstraße 364287 DarmstadtGermany Institute of Plant Sciences University of BernAltenbergrain 213013 BernSwitzerland Biodiversity and Conservation Biology WSL Swiss Federal Research InstituteZürcherstrasse 1118903 BirmensdorfSwitzerland Helmholtz Centre for Environmental Research-UFZ Department of Soil EcologyTheodor-Lieser-Straße 406120 Halle(Saale)Germany German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5e04103 LeipzigGermany Forest Entomology WSL Swiss Federal Research InstituteZürcherstrasse 1118903 BirmensdorfSwitzerland Department of Environmental Systems Science Institute of Terrestrial EcosystemsETH ZürichUniversitätstr 168092 ZürichSwitzerland Environmental Informatics University of MarburgDeutschhausstraße 1235032 MarburgGermany Evolutionary Ecology and Conservation Genomics Ulm UniversityAlbert-Einstein-Allee 1189069 UlmGermany Senckenberg Biodiversity and Climate Research Centre Senckenberganlage 2560325 Frankfurt am MainGermany Geoecology University of TübingenRümelinstraße 19-2372070 TübingenGermany Present address:Department of Sustaina

Background:Forests perform various important ecosystem functions that contribute to ecosystem services.In many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forestry,combining timber production with the supply of other forest ecosystem services.However,it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem services.Based on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition,we develop models to predict the potential supply of 13 ecosystem services.We use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory data.Results:Looking at the potential supply of ecosystem services,we found trade-offs(e.***.between both bark beetle control or dung decomposition and both productivity or soil carbon stocks)as well as synergies(e.***.for temperature regulation,carbon storage and culturally interesting plants)across the 53 most dominant forest types in Germany.No single forest type provided all ecosystem services equally.Some ecosystem services showed comparable levels across forest types(e.***.decomposition or richness of saprotrophs),while others varied strongly,depending on forest structural attributes(e.***.phosphorous availability or cover of edible plants)or tree species composition(e.***.potential nitrification activity).Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental conditions.However,the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree species.Conclusions:Our results show that forest multifunctionality is limited to subsets of ecosystem services.The importance of tree species composition highlights that a lack of multifunctionality at the stand level can be compensated by managing forests at the

关键词： Ecosystem processes and services Forest management Structural diversity Tree species composition Trade-offs and synergies Forest productivity