检索结果-南通市图书馆

Analysis of the inflection points of height-diameter models

Forest Ecosystems 2024年第4期11卷 414-422页

作者： Tzeng Yih Lam Mark J.Ducey Department of Forest resources Management Faculty of ForestryThe University of British Columbia2045-2424 Main MallVancouverBCV6T 1Z4 Canada Department of natural resources and the environment University of New Hampshire114 James HallDurhamNH 03824USA

The inflection point is an important feature of sigmoidal height-diameter(H-D)*** is often cited as one of the properties favoring sigmoidal model ***,there are very few studies analyzing the inflection points of H-D *** goals of this study were to theoretically and empirically examine the behaviors of inflection points of six common H-D models with a regional *** six models were the Wykoff(WYK),Schumacher(SCH),Curtis(CUR),HossfeldⅣ(HOS),von Bertalanffy-Richards(VBR),and Gompertz(GPZ)*** models were first fitted in their base forms with tree species as random effects and were then expanded to include functional traits and spatial *** distributions of the estimated inflection points were similar between the two-parameter models WYK,SCH,and CUR,but were different between the threeparameter models HOS,VBR,and *** produced some of the largest inflection *** and VBR produced concave H-D curves without inflection points for 12.7%and 39.7%of the tree *** species or decreasing shade tolerance resulted in larger inflection *** trends in the estimated inflection points of HOS and VBR were entirely opposite across the ***,HOS could produce concave H-D curves for portions of the *** on the studied behaviors,the choice between two-parameter models may not *** recommend comparing seve ral three-parameter model forms for consistency in estimated inflection points before deciding on *** sigmoidal models to have inflection points does not necessarily mean that they will produce fitted curves with *** study highlights the need to integrate analysis of inflection points into modeling H-D relationships.

关键词： Concavity Forest inventory and analysis Generalized height-diameter models Growth functions Height-diameter functions Mixed-effects modeling Points of inflection Species-specific models

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Calcium carbonate promotes the formation and stability of soil macroaggregates in mining areas of China

引用

Journal of Integrative Agriculture 2024年第3期23卷 1034-1047页

作者： Junyu Xie Jianyong Gao Hanbing Cao Jiahui Li Xiang Wang Jie Zhang Huisheng Meng Jianping Hong Tingliang Li Minggang Xu College of resources and environment Shanxi Agricultural UniversityTaigu 030801China Shanxi Province Key Laboratory of Soil environment and Nutrient resources Taiyuan 030031China College of Land Science and Technology China Agricultural UniversityBeijing 100193China

We studied changes in the concentrations of aggregate-cementing agents after different reclamation times and with different fertilization regimes,as well as the formation mechanism of aggregates in reclaimed soil,to provide a theoretical basis for rapid reclamation of soil fertility in the subsidence area of coal mines in Shanxi Province,*** this study,soil samples of 0–20 cm depth were collected from four fertilization treatments of a longterm experiment started in 2008:no fertilizer (CK),inorganic fertilizer (NPK),chicken manure compost (M),and50%inorganic fertilizer plus 50%chicken manure compost (MNPK).The concentrations of cementing agents and changes in soil aggregate size distribution and stability were *** results showed that the formation of>2 mm aggregates,the aggregate mean weight diameter (MWD),and the proportion of>0.25 mm water-stable aggregates (WR_(0.25)) increased significantly after 6 and 11 years of *** concentration of organic cementing agents tended to increase with reclamation time,whereas free iron oxide (Fed) and free aluminium oxide(Ald) concentrations initially increased but then *** general,the MNPK treatment signi?cantly increased the concentrations of organic cementing agents and CaCO_(3),and CaCO_(3) increased by 60.4%at 11 years after ***,CaCO_(3) had the greatest effect on the stability of aggregates,promoting the formation of>0.25 mm aggregates and accounting for 54.4%of the variance in the proportion and stability of the *** was concluded that long-term reclamation is bene?cial for improving soil *** MNPK treatment was the most effective measure for increasing maize grain yield and concentration of organic cementing agents and CaCO_(3).

关键词： reclamation time manure combined with inorganic fertilizer soil aggregate stability cementing agents CaCO_(3)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhanced remediation of chlorpyrifos-contaminated soil by immobilized strain Bacillus H27

引用

Journal of environmental Sciences 2024年第10期144卷 172-184页

作者： Changrui Liu Shengfang Wen Shuhan Li Yu Tian Lanjun Wang Lusheng Zhu Jun Wang Young Mo Kim Jinhua Wang National Engineering Research Center for Efficient Utilization of Soil and Fertilizer resources Key Laboratory of Agricultural Environment in Universities of ShandongCollege of Resources and EnvironmentShandong Agricultural UniversityTaian 271018China Department of Civil and environmental Engineering Hanyang UniversitySeongdong-guSeoul 04763Korea

Chlorpyrifos is a pesticide widely used in agricultural production with a relatively long residual half-life in *** the problem of residual chlorpyrifos is of universal *** this study,rice hull biochar was used as an immobilized carrier to prepare the immobilized strain H27 for the remediation of chlorpyrifos-contamination *** microorganisms after remediation were investigated by ecotoxicological *** immobilized strain H27 had the highest removal rate of chlorpyrifos when 10%bacterial solution was added to the liquid medium containing 0.075-0.109 mm diameter biochar cultured for 22 *** study on the removal of chlorpyrifos by immobilized strain H27 showed that the initial concentration of chlorpyrifos in solution was 25mg/L,and the removal rate reached 97.4%after 7 days of *** the soil,the removal rate of the immobilized bacteria group increased throughout the experiment,which was significantly higher than that of the free bacteria and biochar treatment *** Biolog-ECO test,T-RFLP and RT-RCR were used to study the effects of the soil microbial community and nitrogen cycling functional genes during chlorpyrifos *** was found that ICP group had the highest diversity index among the four treatment *** microflora of segment containing 114 bp was the dominant bacterial community,and the dominant microflora of the immobilized bacteria group was more evenly *** influence of each treatment group on ammonia-oxidizing bacteria(AOB)was greater than on ammonia-oxidizing archaea(AOA).This study offers a sound scientific basis for the practical application of immobilized bacteria to reduce residual soil pesticides.

关键词： Chlorpyrifos Immobilized microorganisms Soil remediation Soil microorganism

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Does urban technological innovation and cooperation promote its green development? Evidence from cities in the Beijing-Tianjin-Hebei urban agglomeration, China

引用

Journal of Geographical Sciences 2024年第10期 1977-2002页

作者： WANG Kewen MA Haitao Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources Research CAS College of resources and environment University of Chinese Academy of Sciences

The internal technological innovation(IT) and external technological cooperation(ET) of a city are crucial drivers for its green development(GD). Although previous studies have extensively explored the effect of IT on GD, IT, ET and GD have not been integrated into the same framework to explore their relationship. Using panel data of 13 cities in the Beijing-Tianjin-Hebei urban agglomeration, this study revealed the spatio-temporal evolution of GD and analyzed the effects of IT and ET on GD from the perspective of baseline impact,spatial effect and synergy effect. Empirical results demonstrate that the level of urban GD has upgraded and the difference in GD between cities has been narrowed though it decreases from the middle to both ends. IT significantly promotes the growth of GD while ET has an inverted U-shaped effect on GD. Under the influence of spatial spillover, IT has a U-shaped effect on the GD of neighboring cities while the effect of ET on neighboring GD is not significant. Additionally, the interaction between IT and ET has not been effective, leading to an insignificant synergy effect on GD. These findings will provide reference for taking rational advantage of IT and ET to facilitate urban GD.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

The interannual periodicity of precipitation and its links to the large-scale circulations over the Third Pole

引用

Journal of Geographical Sciences 2024年第8期34卷 1457-1471页

作者： LIANG Liqiao LIU Qiang LI Jiuyi State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchCASBeijing 100101China State Key Laboratory of Water environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Key Laboratory for Water and Sediment Sciences Ministry of EducationSchool of EnvironmentBeijing Normal UniversityBeijing 100875China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China

To understand the spatio-temporal variability of precipitation(P)in the Third Pole region(centered on the Tibetan Plateau-TP),it is necessary to quantify the interannual periodicity of P and its relationship with large-scale *** this study,Morlet wavelet transform was used to detect significant(p<0.05)periodic characteristics in P data from meteorological stations in four climate domains in the Third Pole,and to reveal the major large-scale circulations that triggered the variability of periodic P,in addition to bringing large amounts of water *** wavelet transform results were as follows.(1)Significant quasiperiodicity varied from 2 to 11 *** high-frequency variability mode(2 to 6 years quasi-periods)was universal,and the low-frequency variability mode(7 to 11 years quasi-periods)was rare,occurring mainly in the westerlies and Indian monsoon domains.(2)The majority of periods were base periods(53%),followed by two-base *** all stations in the Third Pole(95%)showed one or two periods.(3)Periodicity was widely detected in the majority of years(84%).(4)The power spectra of P in the four domains were dominated by statistically significant high-frequency oscillations(ie.,with short periodicity).(5)Large-scale circulations directly and indirectly influenced the periodic P variability in the different *** mode of P variability in the different domains was influenced by interactions between large-scale circulation features and not only by the dominant circulation and its control of water vapour *** results of this study will contribute to better understanding of the causal mechanisms associated with P variability,which is important for hydrological science and waterresourcemanagement.

关键词： precipitation interannual periodicity Morlet wavelet large-scale circulations Third Pole

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Geographical features and development models of estuarine cities

引用

Journal of Geographical Sciences 2024年第1期34卷 25-40页

作者： CHEN Mingxing XIAN Yue HUANG Yaohuan SUN Zhigang WU Chengbin Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resource and environment University of Chinese Academy of SciencesBejing 100049China State Key Laboratory of resources and environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Zhongke Shandong Dongying Institute of Geography Dongying 257509ShandongChina CAs Engineering Laboratory for Yellow River Delta Modern Agriculture Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China

Cities are the key areas for human beings to achieve sustainable development goals in the *** cities are a special type of coastal city in urgent need of a clear *** paper proposed that estuarine cities are cities developed on the coast where rivers and oceans meet and defined four connotations,including the intersection of rivers and marine water systems,the coordinated development of land and oceans,the location advantages of connecting rivers and seas,and the important fragility of the ecological *** used Hydro SHEDS,OSM,GPW,and urban socioeconomic statistics and selected 50 estuarine cities with large rivers as representatives to summarize the main geographical basis and socioeconomic *** are primarily found in low-altitude,flat regions with average annual temperatures that mainly vary from 10℃to 25℃,relatively abundant precipitation,and extensive biological *** are substantial variations in the socioeconomic features of estuarine *** proposed eight development patterns,including open and inclusive city spirit,high-quality livable cities,high-quality development driven by innovation,integration of internal and external communication with ports and cities,construction of an international financial center,ecological environment protection and restoration,active promotion of cultural tourism,and positive international exchanges.

关键词： estuarine cities great rivers development models sustainability physical geography socioeconomy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Comparison of life cycle assessment of large-scale biogas projects with different raw materials in China

引用

International Journal of Agricultural and Biological Engineering 2024年第2期17卷 268-279页

作者： Jiazheng Sun Youpei Qu Xiaoyi Lyu Xinjie Ding Xinying Miao Mukesh Kumar Awasthi Jingbo Qu School of Energy and environment City University of Hong KongHong Kong 999077China College of Engineering Northeast Agricultural UniversityHarbin 150030China Key Laboratory of Agricultural Renewable resources Utilization Technology and Equipment in Cold Areas of Heilongjiang Province Harbin 150030China College of natural resources and environment Northwest A&F UniversityYangling 712100Shaanxi China

The anaerobic digestion(AD)disposal of stover and cattle manure is of great significance to the development of low-carbon economy and green energy in China,but it will also have an impact on the environment,and the degree of influence is different for various raw *** this study,life cycle assessment(LCA)methods were applied to analyze and compare the impact of corn stovers biogas projects(CSBP)and dairy manure biogas projects(DMBP)on the environment during the whole operation *** results of inventory analysis were evaluated by ReCiPe2016 Hierarchy(H)mid-point(problem-oriented)and end-point(destruction-oriented)method,*** results showed that the net energy efficiency of CSBP was higher(763.903 kW·h/FU)and the greenhouse gas(GHG)emission reduction of DMBP was more(5541.418 kg CO_(2)-eq/FU).The anaerobic digestion(AD)units have the greatest environmental impacts,and human carcinogenic toxicity is the largest environmental impact category(1.16-1.43 PE).The key to reducing environmental impact is reducing the input of chemical substances and the waste of electric *** CSBP and DMBP have a favorable impact on ecosystem quality and resources,and CSBP is more beneficial to the environment(-10.297 Pt).Co-digestion is an important measure to reduce the environmental damage from biogas *** research results provide theoretical support for the selection of raw materials for large-scale biogas projects in China,provide technical basis for reducing the impact of actual operation on the environment,and promote the resource utilization of agricultural waste and carbon dioxide emission reduction and sequestration.

关键词： life cycle assessment environmental impact assessment large-scale biogas projects bioenergy carbon dioxide emission reduction

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A four-band index for both liquid and solid water and its applications in the Aral Sea Basin

引用

Science China Earth Sciences 2024年第3期67卷 769-788页

作者： Bing YUE Xi CHEN Saibo LI Zhengping DU John WILSON Junhui YANG Yimen JIAO Shuangyan HUANG Chenghu ZHOU Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China College of resources and environment University of Chinese Academy of SciencesBeijing 100049China Institute of Geographical Sciences and natural resources Research Chinese Academy of SciencesBeijing 100101China Spatial Sciences Institute University of Southern CaliforniaLos AngelesCA 90089-0374USA

Various investigations have been conducted to analyze the water-coverage area of the Aral Sea and the Aral Sea Basin(ASB). However, the investigations incorporated considerable uncertainty and the used water indices had misclassification problem, which made different research groups present different results. Thus we first ascertain the boundaries of the ASB, the Syr and Amu river basins as well as their upper, middle and lower reaches. Then a four-band index for both liquid and solid water(ILSW) is proposed to address the misclassification problems of the classic water indices. ILSW is calculated by using the reflectance values of the green, red, near infrared, and thermal infrared bands, which combines the normalized difference water index(NDWI) and land surface temperature(LST) together. Validation results show that the ILSW water index has the highest accuracy by far in the Aral Sea Basin. Our results indicate that annual average decline of the water-coverage area was 963 km^(2) in the southern Aral Sea, whereas the northern Aral Sea has experienced little change. In the meanwhile, permanent ice and snow in upper reach of ASB has retreated considerably. Annual retreating rates of the permanent ice and snow were respectively 6233and 3841 km^(2) in upper reaches of Amu river basin(UARB) and Syr river basin(USRB). One of major reasons is that climate has become warmer in ASB. The climate change has caused serious water deficit problem. The water deficit had an increasing trend since the 1990s and its increasing rates was 3.778 billion m^(3) yearly on average. The total water deficit was 76.967 billion m^(3) on average in the whole area of ASB in the 2010s. However, up reaches of Syr river basin(USRB), a component area of ASB, had water surplus of 25.461 billion m^(3). These conclusions are useful for setting out a sustainable development strategy in ASB.

关键词： Aral Sea Basin Syr river basin Amu river basin Water indices Water-coverage area Water deficit Climate change

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Optimized nitrogen application for maximizing yield and minimizing nitrogen loss in film mulching spring maize production on the Loess Plateau,China

引用

Journal of Integrative Agriculture 2024年第5期23卷 1671-1684页

作者： Qilong Song Jie Zhang Fangfang Zhang Yufang Shen Shanchao Yue Shiqing Li State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau College of Natural Resources and EnvironmentNorthwestA&FUniversityYangling712100China Life Science Department Luoyang Normal UniversityLuoyang 471934China

Excessive use of N fertilizers(driven by high-yield goals)and its consequent environmental problems are becoming increasingly acute in agricultural systems.A 2-year field experiment was conducted to investigate the effects of three N application methods(application of solid granular urea once(OF)or twice(TF),application of solid granular urea mixed with controlled-release urea once(MF),and six N rates(0,60,120,180,240,and 300 kg N ha^(-1))on maize yield,economic benefits,N use efficiency,and soil N balance in the maize(Zea mays L.)film mulching system on the Loess Plateau,*** grain yield and economic return of maize were significantly affected by the N rate and application *** with the OF treatment,the MF treatment not only increased the maize yield(increased by 9.0-16.7%)but also improved the economic return(increased by 10.9-25.8%).The agronomic N use efficiency(NAE),N partial factor productivity(NPFP)and recovery N efficiency(NRE)were significantly improved by 19.3-66.7,9.0-16.7 and 40.2-71.5%,respectively,compared with the OF *** economic optimal N rate(EONR)of the OF,TF,and MF was 145.6,147.2,and 144.9 kg ha^(-1) in 2019,and 206.4,186.4,and 146.0 kg ha^(-1) in 2020,*** apparent soil N loss at EONR of the OF,TF,and MF were 97.1-100.5,78.5-79.3,and 50.5-68.1 kg ha^(-1),*** results support MF as a one-time N application method for delivering high yields and economic benefits,with low N input requirements within film mulching spring maize system on the Loess Plateau.

关键词： maize yield N management economic optimal N rate Loess Plateau

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Variation characteristics of acid rain in Zhuzhou,Central China over the period 2011-2020

引用

Journal of environmental Sciences 2024年第4期138卷 496-505页

作者： Jiahao Ren Liquan Zhu Xi Zhang Yuqian Luo Xuecai Zhong Bowen Li Yuwen Wang Kai Zhang State Key Laboratory of environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Zhuzhou environment Monitoring Center Zhuzhou 412000China Faculty of environmental Engineering The University of Kitakyushu1–1 HibikinoWakamatsuKitakyushuFukuoka 808-0135Japan College of natural resources and environment South China Agricultural UniversityGuangzhou 510642China

Zhuzhou was one of the most polluted cities in China with the serious acid *** to the implementation of air pollution control measures from 2016 to 2018,the acid rain pollution in this city has *** order to understand the recent situation,a comprehensive study on the acid rain was carried out from January 2011 to December *** pH values during the study period varied from 3.3 to 7.5,with a volume-weighted mean value of *** predominant acidic components of the precipitation were SO_(4)^(2-)and NO_(3)^(-),accounting for 89.3% of the total *** ratio of non-sea-salt SO_(4)^(2-)to NO_(3)^(-)showed a decreasing trend,revealing that the pollution type of acid rain changed from sulfuric acid type to sulfuric acid and nitric acid compound *** correlation analysis(p<0.05)showed that SO_(4)^(2-)was positively correlated with NH_(4)^(+),Ca^(2+),and Mg^(2+);hence,it predominated in precipitation as(NH_(4))_(2)SO_(4),NH_(4)HSO_(4),CaSO_(4),and MgSO_(4).Significant positive correlation of Ca^(2+)with Mg^(2+)shows that they may originated mainly from *** positive correlation between SO_(4)^(2-)and F^(-)and Cl^(-)indicate that their source may be related to the non-ferrous metal smelting industry in *** correlation analysis shows that emissions from the non-ferrous metal smelting industry in the area have a large significant on SO_(4)^(2-)and F^(-)in precipitation,while Cl^(-)may still be emitted from other anthropogenic sources.

关键词： Acid rain pH Chemical composition Neutralization factor Correlation analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：