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Book review “Continuous Cover Forestry – Theories, Concepts, and Implementation” by Arne Pommerening
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作者 zhonghua zhao Gangying Hui 《Forest Ecosystems》 SCIE CSCD 2023年第6期774-775,共2页
Arne Pommerening,Continuous Cover Forestry:Theories,Concepts,and Implementation.WILEY(2023),pp.416;ISBN:978-1-119-89532-9(E-BOOK),ISBN:978-1-119-89530-5(PRINT).Forests are the largest,most complex,and most diverse ter... Arne Pommerening,Continuous Cover Forestry:Theories,Concepts,and Implementation.WILEY(2023),pp.416;ISBN:978-1-119-89532-9(E-BOOK),ISBN:978-1-119-89530-5(PRINT).Forests are the largest,most complex,and most diverse terrestrial ecosystems,known as the overall regulator of nature and the“lungs of the earth”.They play an important role in maintaining global ecological balance and biodiversity,mitigating climate change,and promoting economic development.Therefore,strengthening the protection and cultivation of forest resources is an important way to achieve sustainable development.Countries around the world are actively exploring and developing ways to achieve sustainable forest management. 展开更多
关键词 PRINT FOREST strengthening
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Designing near-natural planting patterns for plantation forests in China 被引量:8
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作者 Gongqiao Zhang Gangying Hui +4 位作者 Yanbo Hu zhonghua zhao Xiuling Guan Klaus von Gadow Ganggang Zhang 《Forest Ecosystems》 SCIE CSCD 2019年第3期236-248,共13页
Background: China has a long tradition of managing planted forests. Different species of Populus, Eucalyptus, Larix, Cunninghamia and Pinus are planted to satisfy the local demand for wood products and provide ecologi... Background: China has a long tradition of managing planted forests. Different species of Populus, Eucalyptus, Larix, Cunninghamia and Pinus are planted to satisfy the local demand for wood products and provide ecological services at the same time. Evidence of the greater resilience of natural forests provides the motivation to develop asymmetric planting patterns, which is the focus of this study. We present a new method for designing plantation patterns that follow those observed in natural ecosystems and to maintain some regularity for operational convenience. Methods: Based on the uniform angle index, we analyzed the spatial structure of six natural forests in different regions of China. The uniform angle index describes the degree of spatial uniformity of the n nearest neighbors of a given reference tree. Accordingly, we identified all possible patterns of a neighborhood group within a regular planting pattern and developed a method to optimize planting point arrangements that contain some randomness as well as a minimum degree of regularity. Results:(1) There are 13 types of structural units in a regular planting, including seven random units, five even units and one cluster unit;(2) Five near-natural arrangements are presented with a minimum proportion of 50% of random units. These five arrangements represent a combination of regularity for operational convenience and asymmetry. Conclusions: The new planting patterns developed in this study are expected to increase the asymmetric competition and resilience of these important ecosystems. Some experimental plantings, based on our findings, have already been established, e.g., in Pinus tabulaeformis plantations in Tianshui, Gansu Province, and in a Populus deltoides plantation in Fangshan near Beijing. 展开更多
关键词 PLANTATION NEAR-NATURAL FOREST UNIFORM angle index FOREST spatial structure ASYMMETRIC COMPETITION
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Global woodland structure from local interactions:new nearest-neighbour functions for understanding the ontogenesis of global forest structure 被引量:3
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作者 Arne Pommerening Hongxiang Wang zhonghua zhao 《Forest Ecosystems》 SCIE CSCD 2020年第2期290-300,共11页
Background:A number of hypotheses and theories,such as the Janzen-Connell hypothesis,have been proposed to explain the natural maintenance of biodiversity in tropical and temperate forest ecosystems.However,to date th... Background:A number of hypotheses and theories,such as the Janzen-Connell hypothesis,have been proposed to explain the natural maintenance of biodiversity in tropical and temperate forest ecosystems.However,to date the details of the processes behind this natural maintenance are still unclear.Recently two new nearest-neighbour characteristics were proposed and in this paper we demonstrate how they can contribute to a better understanding of the ontogenesis of global forest structure from localised neighbourhoods.Methods:We applied the new species and size segregation functions together with appropriate test procedures to four example woodland data sets from China at Daqingshan,Jiaohe,Jiulongshan and Xiaolongshan forest regions.In addition we quantified the morphology of the new characteristics and modelled a neighbourhood allometric coefficient linking the two functions.Results:The results revealed quite different species segregation patterns with both conspecific and heterospecific attraction.We found these to be generally matched by equivalent size segregation patterns of attraction of similar and different sizes.It was straightforward to model the size segregation function from the knowledge of the species segregation function by estimating a neighbourhood allometric coefficient.Conclusions:The new characteristics have helped to quantify the extent and rate of decline of neighbourhood interactions in terms of spatial species and size diversity.Through the allometric neighbourhood coefficient the analysis highlighted once more how closely related species and size segregation are,thus supporting the minglingsize hypothesis.Using both a traditional and a restricted random-labelling test has provided a valuable tool for understanding the exact nature of species-mingling and size-inequality relationships. 展开更多
关键词 Species segregation function Size segregation function Mingling-size hypothesis Neighbourhood allometric coefficient random labelling
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Direct image-based fractal characterization of micromorphology of calcium carbonate fouling crystals 被引量:1
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作者 Xiaokai Xing zhonghua zhao JianhangWu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第2期466-476,共11页
Researches on macroscopic fouling behavior and micromorphology are usually conducted separately.In this paper,the relationship between the macroscopic fouling behavior and micromorphology on different materials is est... Researches on macroscopic fouling behavior and micromorphology are usually conducted separately.In this paper,the relationship between the macroscopic fouling behavior and micromorphology on different materials is established.A direct fractal-characterization approach based on the micrographs of calcium carbonate fouling crystals is presented.The box-counting method is used to characterize the fouling crystals.For fractal measurements,t-distribution tests of linear regression hypothesis are performed at the significance level of 0.01.If all listed absolute t-statistics with the minimum of 164 are higher than the corresponding t value,the fouling crystals are determined as fractal,with a confidence level of 99%.The fractal dimensions obtained from the micrographs of different visual fields of a specimen are demonstrated to be almost identical,with maximum and minimum relative values of 4.42%and 0.75%,respectively,and standard deviations ranging from 0.0062 to 0.0266.The irregularity of the crystal morphology indicates larger fractal dimensions.Comparison and analysis of the relationship between macroscopic fouling behavior and micromorphology show that the larger fractal dimension of crystal morphology suggests a small amount of surface fouling.Thus,the reasons for the differences in the macroscopic fouling behaviors of different materials are revealed geometrically. 展开更多
关键词 CALCIUM CARBONATE FOULING FRACTAL dimension MICROMORPHOLOGY
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硅藻土基清洁剂的制备及应用
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作者 赵中华 张健 +2 位作者 盛雪茹 李娜 平清伟 《日用化学工业》 CAS 北大核心 2022年第3期270-277,共8页
通过在传统清洁产品中引入硅藻土,优化表面活性剂、辅料种类和配比,制备了新型硅藻土基清洁剂,主要应用在织物和玻璃瓶方面,并探究清洁效果、互染性、标签和霉斑去除率等性能。硅藻土基织物清洁剂较优配方为硅藻土用量5%,AEO-9 15%,6501... 通过在传统清洁产品中引入硅藻土,优化表面活性剂、辅料种类和配比,制备了新型硅藻土基清洁剂,主要应用在织物和玻璃瓶方面,并探究清洁效果、互染性、标签和霉斑去除率等性能。硅藻土基织物清洁剂较优配方为硅藻土用量5%,AEO-9 15%,6501 5%,AEO-7 5%,硅酸钠0.3%、棕榈酸2%、柠檬酸钠3%;玻璃瓶清洁剂的较优配方为硅藻土用量5%,AEO-9 15%,6501 5%,AEO-7 5%,硅酸钠3.6%,硫酸钠1.5%,葡萄糖酸钠1.8%,氢氧化钠7.5%。所制备的清洁剂对炭黑、蛋白和皮脂污布的清洁白度差较优于市售普通清洁产品。在织物清洁方面,产品可实现被清洁织物的零互染;在玻璃清洁方面,温度在70℃时脱标率为100%;清洁剂用量为2%时,霉斑去除率达100%。硅藻土能用于配制不同清洁剂。 展开更多
关键词 硅藻土 清洁剂 互染性 脱标率 霉斑去除
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The Evolutionary Rules of Production System
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作者 zhonghua zhao Xueliang Pei 《Chinese Business Review》 2005年第2期49-51,共3页
The competition among modem enterprises has been converted from products to capability. As the basis of competition, production system can't win the market unless it takes advantage of its capability in competition. ... The competition among modem enterprises has been converted from products to capability. As the basis of competition, production system can't win the market unless it takes advantage of its capability in competition. Here in this article, the evolutionary rules of production system contributing to the establishment, renovation, reform, invention and promotion of the production of modem enterprises are observed. 展开更多
关键词 production system rule evolution
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The Condition of Fostering Core Competitiveness of Equipment Manufacture Industry in Our Country
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作者 zhonghua zhao Xueliang Pei 《Chinese Business Review》 2005年第6期15-17,共3页
The equipment manufacture industry occupies the important position in our national economy, and the research on its core competitiveness is an important aspect of protecting the healthy development of equipment manufa... The equipment manufacture industry occupies the important position in our national economy, and the research on its core competitiveness is an important aspect of protecting the healthy development of equipment manufacture industry. Researches on core competitiveness of equipment manufacture industry are to cultivate, strengthen and perfect enterprise's core competitiveness and bring about the advance to enterprise. 展开更多
关键词 equipment manufacture industry core competitiveness condition of fostering
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Physically modulated phytoplankton production and export at submesoscales in the oligotrophic South China Sea Basin
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作者 zhonghua zhao Mengdi XU +4 位作者 Bangqin HUANG Wenfang LU Hongshuai QI Feng CAI Yuwu JIANG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第8期2681-2698,共18页
Oceanic submesoscales can significantly influence phytoplankton production and export owing to their similar timescales of days.Based on two-year Biogeochemical Argo(BGC-Argo) observations,this study investigated the ... Oceanic submesoscales can significantly influence phytoplankton production and export owing to their similar timescales of days.Based on two-year Biogeochemical Argo(BGC-Argo) observations,this study investigated the development of submesoscale instabilities,particularly symmetric and mixed-layer baroclinic instabilities,and their impacts on biological production and export in the oligotrophic South China Sea basin.In the northern basin,near-surface winter blooms consistently cooccurred with seasonally deepened mixed layers.However,significantly stronger and weaker winter blooms were observed over two consecutive winters within the BGC-Argo observation period.During the first winter,symmetric-instability-induced upward nutrient entrainment played a crucial role in initiating the strong winter bloom in early December,when the mixed layer was approximately 20–30 m shallower than the nutricline.This bloom occurred approximately 20–30 days earlier than that anticipated owing to the contact between the seasonally deepened mixed layer and mesoscale-cyclone-induced uplifted nutricline.The symmetric instability also facilitated the export of fixed phytoplankton carbon from the surface to deeper layers.Conversely,during the second winter,remarkably intense mixed-layer baroclinic instability associated with an intense mesoscale anticyclone led to more significant shoaling of the mixed layer compared to the nutricline,thus increasing the vertical distance between the two layers.Under this condition,upward nutrient injection,phytoplankton bloom,and carbon export were suppressed.In contrast,the BGC-Argo float in the central basin revealed significantly inhibited seasonality of phytoplankton biomass and submesoscale instabilities compared to those in the northern basin,primarily owing to the significantly shallower winter mixed layer. 展开更多
关键词 Submesoscale instability PHYTOPLANKTON Nutrient transport BGC-Argo South China Sea
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China’s larch stock volume estimation using Sentinel-2 and LiDAR data
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作者 Tao Yu Yong Pang +12 位作者 Xiaojun Liang Wen Jia Yu Bai Yilin Fan Dongsheng Chen Xianzhao Liu Guang Deng Chonggui Li Xiangnan Sun Zhidong Zhang Weiwei Jia zhonghua zhao Xiao Wang 《Geo-Spatial Information Science》 SCIE EI CSCD 2023年第3期392-405,共14页
Forest Stock Volume(FSV)is one of the key indicators in forestry resource investigation and management on local,regional,and national scales.Limited by the saturation problems of optical satellite remote-sensing image... Forest Stock Volume(FSV)is one of the key indicators in forestry resource investigation and management on local,regional,and national scales.Limited by the saturation problems of optical satellite remote-sensing imagery in the retrieving of stock volume,and the high cost of Light Detection And Ranging(LiDAR)data,it is still challenging to estimate FSV in a large area using single-sensor remote-sensing data.In this paper,a method integrated multispectral satellite imagery and LiDAR data was developed to map stock volume in a large area.A random forest model was adopted to estimate the stock volume of larch forest in China based on the training samples from the Airborne Laser Scanning(ALS)-derived stock volume and corresponding Sentinel-2 imagery.Validation using National Forest Inventory(NFI)data,ALS-derived stock volume and ground investigation data demonstrated that the estimated stock volume had a high accuracy(R2=0.59,RMSE=59.69 m^(3)/ha,MD=39.96 m^(3)/ha when validated with NFI data;R2 ranged from 0.77 to 0.85,RMSE ranged from 38.68 m^(3)/ha to 67.38 m^(3)/ha,MD ranged from 24.90 m^(3)/ha to 37.27 m^(3)/ha when validated with ALS stock volume;R2=0.42,RMSE=79.10 m^(3)/ha,MD=62.06 m^(3)/ha when validated with field investigation data).Results of this paper indicated the applicability of estimating stock volume of larch forest in a large area by combining Sentinel-2 data and airborne LiDAR data. 展开更多
关键词 Sentinel-2 LIDAR stock volume LARCH validation
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Effect of Yiqiyangyin recipe on heparanase and nephrin in rats with adriamycin-induced nephropathy 被引量:4
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作者 Wen Sun Yongrui He +6 位作者 Jian Yu Yanyan Lin Yonghong Wang Xia Gao Ying Wang zhonghua zhao Xueguang Liu 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第3期334-342,共9页
OBJECTIVE: To discuss the mechanism of Yiqiyang- yin recipe in rats with adriamycin (ADR)-induced ne- phropathyo METHODS: We randomly divided 30 Sprague-Daw- ley rats into 5 groups: control, model, glucocorti- co... OBJECTIVE: To discuss the mechanism of Yiqiyang- yin recipe in rats with adriamycin (ADR)-induced ne- phropathyo METHODS: We randomly divided 30 Sprague-Daw- ley rats into 5 groups: control, model, glucocorti- coid, Chinese herb, and Chinese herb plus glucocor- ticoid groups. The 24-h urine volume was collected on days 7, 14, 21, and 28 after ADR injection, and all rats were killed on day 28. We measured the 24-h levels of urinary protein, serum cholesterol, and se- rum triglycerides, and renal function of all rats by using routine biochemical methods. Pathological changes in the rat kidneys were observed under light and electron microscopes. Heparanase (HPA) mRNA expression levels were measured using re-al-time fluorescence-quantitative polymerase chain reaction. Urine levels of HPA in all groups were measured using enzyme-linked immunosor- bent assay. The expression of nephrin was detected by immunohistochemical staining and quantitative- ly analyzed using Motic image analysis 3.2 software. RESULTS: The levels of urinary protein and serum triglycerides and cholesterol in rats with ADR-in- duced nephropathy increased on day 14. The se- rum albumin levels simultaneously decreased. All the changes reached the peak on day 28. Examina- tion under the light microscope showed inflamma- tory cells and slight fibroplasia in the renal intersti- tium in the model group, but fewer inflammatory cells were observed in the intervention groups than those in the model group. Examination under the electron microscope showed extensive fusion of foot processes in ADR rats. HPA mRNA expres- sion was higher in the model group than that in the control group. The HPA mRNA levels in the in- tervention groups, especially in the Chinese herb group, and Chinese herb plus glucocorticoid group were significantly lower than the level in the model group. The HPA expression levels correlated signifi- cantly with the proteinuria level. No significant dif- ference was found in the HPA level in urine be- tween the intervention groups and the model group, whereas the model group had a higher uri- nary HPA level than the control group. Nephrin mRNA expression levels in the model group were higher than those in the control group. Nephrin mRNA expression levels were significantly lower in the intervention groups than that in the model group, especially the Chinese herb plus glucocorti- cold group. Compared with the control group, themodel group showed increased nephrin expression in the kidney. Nephrin levels in the other groups, es- pecially in the Chinese herb plus glucocorticoid group, were significantly lower than that in the model group. The nephrin levels in the kidney were negatively correlated with the proteinuria level. CONCLUSION: Yiqiyangyin recipe could attenuate foot process injury particularly in combination with a steroid reduce the development of proteinuria possibly by inhibition of HPA in the kidney, and reg- ulate the expression of nephrin in rats with ADR-in- duced nephropathy. Our study showed that treat- ment with Yiqiyangyin recipe plus glucocorticoid was better than a singular intervention, and we ex- plored the pharmacological mechanism of this combination by biochemical and molecular biologi- cal analysis to provide a basis for clinical applica- tion. 展开更多
关键词 Benefiting Qi for nourishing Yin Chi-nese medical formula DOXORUBICIN PROTEINURIA HEPARANASE NEPHRIN
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A fundamental representation of quantum generalized Kac-Moody algebras with one imaginary simple root
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作者 Jiangrong CHEN zhonghua zhao 《Frontiers of Mathematics in China》 SCIE CSCD 2015年第5期1041-1056,共16页
We consider the Borcherds-Cartan matrix obtained from a symmetrizable generalized Cartan matrix by adding one imaginary simple root. We extend the result of Gebert and Teschner [Lett. Math. Phys., 1994, 31: 327-334] ... We consider the Borcherds-Cartan matrix obtained from a symmetrizable generalized Cartan matrix by adding one imaginary simple root. We extend the result of Gebert and Teschner [Lett. Math. Phys., 1994, 31: 327-334] to the quantum case. Moreover, we give a connection between the irreducible dominant representations of quantum Kac-Moody algebras and those of quantum generalized Kac-Moody algebras. As the result, a large class of irreducible dominant representations of quantum generalized Kac-Moody algebras were obtained from representations of quantum Kac-Moody algebras through tensor algebras. 展开更多
关键词 Quantum generalized Kac-Moody algebra tensor algebra fundamental representation
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