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Coupling and Long-term Change Characteristics of Forest Carbon Sink and Forestry Economic Development in China
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作者 Ying ZHANG Na MENG Keren ZHANG 《Asian Agricultural Research》 2024年第7期1-11,共11页
[Objectives]To analyze the changes in of forest carbon sink and forestry economic development,provide reference for relevant management decisions,ecological governance and resource and environment management,and promo... [Objectives]To analyze the changes in of forest carbon sink and forestry economic development,provide reference for relevant management decisions,ecological governance and resource and environment management,and promote the development of green low-carbon economy in China.[Methods]Based on the data of six forest resource inventories from 1989 to 2018 and related studies,the comprehensive evaluation model of forest carbon sink and forestry economic development,the coupling degree model of forest carbon sink and forestry economic development,and the coupling coordination degree model of forest carbon sink and forestry economic development were adopted.The coupling degree of forest carbon sink and forestry economic development from 1992 to 2018 was analyzed.Stepwise regression and ARIMA model were used to analyze the influencing factors and lagging characteristics of forest carbon sink.The coupling degree between forest carbon sink and forestry economic development in China from 2019 to 2030 was predicted by autoregression and ADF test.The coupling between forest carbon sink and forestry economic development in China and its long-term change characteristics were also discussed in this study.[Results](i)The investment of ecological construction and protection,the actual investment of forestry key ecological projects,GDP and the import of forest products had a significant impact on forest resources carbon stock.The total output value of forestry industry,the actually completed investment of forestry key ecological projects and the export volume of forest products had a significant impact on the forest carbon sink,and the actually completed investment of forestry key ecological projects has the greatest impact on the two.(ii)The impact of actually completed investment of forestry key ecological projects had a lag of 2 years on the forest resources carbon stock and a lag of 1 year on the forest carbon sink.When investing in forest carbon sink,it is necessary to make a good plan in advance,and do a good job in forest resources management and time optimization.(iii)From 1992 to 2018,the coupling degree of forest resources carbon stock,forest carbon sink and long-term development of forestry economy in China was gradually increasing.Although there were some fluctuations in the middle time,the coupling degree of forest resources carbon stock and the long-term development of forestry economy increased by 9.24%annually,and the degree of coupling coordination increased from"serious imbalance"in 1992 to"high-quality coordination"in 2018.From 1993 to 2018,the coupling degree of forest carbon sink and long-term development of forestry economy increased by 9.63%annually,slightly faster than the coupling coordination degree of forest resources carbon stock and long-term development of forestry economy.The coordination level also rose from level 2 in 1993 to level 10 in 2018.(iv)The prediction shows that the coupling coordination degree of forest resources carbon stock,forest carbon sink and the long-term development of forestry economy would increase from 2019 to 2030.The coupling coordination degree(D)values of both were close to 1,the coordination level was also 10 for a long time,and the degree of coupling coordination was also maintained at the"high-quality coordination"level for a long time.[Conclusions]Forest has multiple benefits of society,economy and ecology,and forest carbon sink is only a benefit output.The long-term coupling analysis of forest carbon sink and forestry economic development is a key point to multiple benefit analysis.The analysis shows that the spillover effect and co-evolution effect of forest carbon sink in China are significant.From 1992 to 2018,the coupling coordination degree of forest carbon sink and forestry economic development was gradually rising.The prediction analysis also indicate that the coupling coordination degree between the forest carbon sink and the long-term development of forestry economy will remain at the level of"high-quality coordination"for a long time from 2019 to 2030.Therefore,improving the level of forest management and maintaining the current trend of increasing forest resources are the key to achieving the goal of carbon peaking and carbon neutrality in China. 展开更多
关键词 Forest resources carbon stock Forest carbon sink Coupling coordination degree Forestry economic development long-term trend
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CLIMATE CHANGE:LONG-TERM TRENDS AND SHORT-TERM OSCILLATIONS 被引量:1
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作者 高新全 张欣 钱维宏 《Journal of Tropical Meteorology》 SCIE 2006年第2期139-149,共11页
Identifying the Northern Hemisphere (NH) temperature reconstruction and instrumental data for the past 1000 years shows that climate change in the last millennium includes long-term trends and varioas oscillations. ... Identifying the Northern Hemisphere (NH) temperature reconstruction and instrumental data for the past 1000 years shows that climate change in the last millennium includes long-term trends and varioas oscillations. Two long-term trends and the quasi-70-year oscillation were detected in the global temperature series tbr the last 140 years and the NH millennium series. One important feature was emphasized that temperature decreases slowly but it increases rapidly based on the analysis of different series. Benefits can be obtained of climate change from understanding various long-term trends and oscillations. Millennial temperature proxies from the natural climate system and time series of nonlinear model system are used in understanding the natural climate change and recognizing potential benefits by using the method of wavelet transform analysis. The results from numerical modeling show that major oscillations contained in numerical solutions on the interdecadal timescale are consistent with that of natural proxies. It seems that these oscillations in the climate change are not directly linked with the solar radiation as an external tbrcing. This investigation may conclude that the climate variability at the interdecadal timescale strongly depends on the internal nonlinear effects in the climate system. 展开更多
关键词 climate change trend and oscillation natural climate system nonlinear model system
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Comparative Analysis of Climatic Change Trend and Change-Point Analysis for Long-Term Daily Rainfall Annual Maximum Time Series Data in Four Gauging Stations in Niger Delta
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作者 Masi G. Sam Ify L. Nwaogazie +4 位作者 Chiedozie Ikebude Jonathan O. Irokwe Diaa W. El Hourani Ubong J. Inyang Bright Worlu 《Open Journal of Modern Hydrology》 2023年第4期229-245,共17页
The aim of this study is to establish the prevailing conditions of changing climatic trends and change point dates in four selected meteorological stations of Uyo, Benin, Port Harcourt, and Warri in the Niger Delta re... The aim of this study is to establish the prevailing conditions of changing climatic trends and change point dates in four selected meteorological stations of Uyo, Benin, Port Harcourt, and Warri in the Niger Delta region of Nigeria. Using daily or 24-hourly annual maximum series (AMS) data with the Indian Meteorological Department (IMD) and the modified Chowdury Indian Meteorological Department (MCIMD) models were adopted to downscale the time series data. Mann-Kendall (MK) trend and Sen’s Slope Estimator (SSE) test showed a statistically significant trend for Uyo and Benin, while Port Harcourt and Warri showed mild trends. The Sen’s Slope magnitude and variation rate were 21.6, 10.8, 6.00 and 4.4 mm/decade, respectively. The trend change-point analysis showed the initial rainfall change-point dates as 2002, 2005, 1988, and 2000 for Uyo, Benin, Port Harcourt, and Warri, respectively. These prove positive changing climatic conditions for rainfall in the study area. Erosion and flood control facilities analysis and design in the Niger Delta will require the application of Non-stationary IDF modelling. 展开更多
关键词 Rainfall Time Series Data Climate change trend Analysis Variation Rate change Point Dates Non-Parametric Statistical Test
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Trend of Salt Lake Changes in the Background of Global Warming and Tactics for Adaptation to the Changes 被引量:12
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作者 ZHENGMianping QIWen +2 位作者 JIANGXianfeng ZHAOYuanyi LIMinghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期795-807,共13页
Salt lakes are a mirror of climatic changes and provide holographic records of environmental changes of lakes. According to a study of geological hazards in typical salt lake areas in China and other regions, the auth... Salt lakes are a mirror of climatic changes and provide holographic records of environmental changes of lakes. According to a study of geological hazards in typical salt lake areas in China and other regions, the authors explain how geological hazards in salt lake areas are caused by natural agents and how humans can seek benefits, avoid hazards and reduce losses on the premise that they have monitored and mastered the trend of salt lake changes in advance and even can store flood and recharge water in lakes and extract saline resources. The climate in western China is probably turning from warm-dry to warm-moist. The authors analyze the change trend of salt lakes sensu lato (with salinity≥0.3 wt% (NaCl)eq) and salt lakes sensu stricto (with salinity ≥3.5 wt% (NaCl)eq) in China in such climatic conditions and distinguish three types of salt lake areas (i.e. lake water rising type, lake water falling type and lake water rising and unstable type) according to the characteristics of lake water rising and shrinking. In order to conform to the climatic and lake changes in China's salt lake areas, the authors propose to add and improve hydrological and meteorological observation stations and integrate observations with remote sensing monitoring in important salt lake areas and set up multidisciplinary and interdepartmental basic projects to monitor and study recent climatic and environmental changes in salt lake areas of western China. Moreover, it is necessary to build additional flood-control and drought-preventing water conservancy facilities in key salt lake areas and work out measures for ecological protection in salt lake areas. Full consideration should be given to the influence of flooding when building saltfields and implementing capital projects. 展开更多
关键词 global warming geological hazard of salt lake trend of salt lake change salt lake water rising and shrinking types tactics for adaptation to change
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Analysis on Long-Term Change of Sea Surface Temperature in the China Seas 被引量:16
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作者 LIU Qinyu ZHANG Qi 《Journal of Ocean University of China》 SCIE CAS 2013年第2期295-300,共6页
Long-term change of sea surface temperature (SST) in the China Seas from 1900 to 2006 is examined based on two different observation datasets (HadlSSTI and HadSST3). Similar to the Atlantic, SST in the China Seas ... Long-term change of sea surface temperature (SST) in the China Seas from 1900 to 2006 is examined based on two different observation datasets (HadlSSTI and HadSST3). Similar to the Atlantic, SST in the China Seas has been well observed during the past 107 years. A comparison between the reconstructed (HadISSTI) and un-interpolated (HadSST3) datasets shows that the SST wanning trends from both datasets are consistent with each other in most of the China Seas. The warming trends are stronger in winter than in summer, with a maximum rate of SST increase exceeding 2.7℃ (100year)-I in the East China Sea and the Taiwan Strait during winter based on HadISSTI. However, the SST from both datasets experienced a sudden decrease after 1999 in the China Seas. The estimated trend from HadlSSTI is stronger than that fi'om HadSST3 in the East China Sea and the east of Taiwan Island, where the difference in the linear SST warming trends are as large as about 1℃ (100year)-I when using respectively HadISST1 and HadSST3 datasets. When compared to the linear winter warnling trend of the land surface air temperature (1.6℃ (100 year)-1), HadSST3 shows a more reasonable trend of less than 2.1℃( 100 year)-1 than HadISST 1 's trend of larger than 2.7℃ ( 100 year)-1 at the mouth of the Yangtze River. The restllts also indicate large uncertainties in the estimate of SST warming patterns. 展开更多
关键词 long-term linear trend sea surface temperature China Seas reconstructed data un-interpolated data UNCERTAINTIES
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Climate change trend and its effects on reference evapotranspiration at Linhe Station, Hetao Irrigation District 被引量:5
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作者 Xu-ming WANG Hai-jun LIU +1 位作者 Li-wei ZHANG Rui-hao ZHANG 《Water Science and Engineering》 EI CAS CSCD 2014年第3期250-266,共17页
Linhe National Meteorological Station, a representative weather station in the Hetao Irrigation District of China, was selected as the research site for the present study. Changes in climatic variables and reference e... Linhe National Meteorological Station, a representative weather station in the Hetao Irrigation District of China, was selected as the research site for the present study. Changes in climatic variables and reference evapotranspiration (ET0 ) (estimated by the Penman-Monteith method) were detected using Mann-Kendall tests and Sen's slope estimator, respectively. The authors analyzed the relationship between the ET0 change and each climatic variable's change. From 1954 to 2012, the air temperature showed a significant increasing trend, whereas relative humidity and wind speed decreased dramatically. These changes resulted in a slight increase in ETo. The radiative component of total ET0 increased from 50% to 57%, indicating that this component made a greater contribution to the increase in total ETo than the aerodynamic component, especially during the crop growing season (from April to October). The sensitivity analysis showed that ETo in Hetao is most sensitive to mean daily air temperature (11.8%), followed by wind speed (-7.3%) and relative humidity (4.8%). Changes in sunshine duration had only a minor effect on ET0 over the past 59 years. 展开更多
关键词 climatic variables reference evapotranspiration change trend Mann-Kendall test sensitivity analysis
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Quantitative contributions of climate change and human activities to vegetation dynamics in the Zoige Plateau from 2001 to 2020
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作者 GAO Bing LIU Enqin +4 位作者 YANG Yang YANG Man YAO Yang GUAN Lei FENG Yiwen 《Journal of Mountain Science》 SCIE CSCD 2024年第9期3031-3046,共16页
Climate change and human activities such as overgrazing and rapid development of tourism simultaneously affected the vegetation of the Zoige Plateau.However,the spatiotemporal variations of vegetation and the relative... Climate change and human activities such as overgrazing and rapid development of tourism simultaneously affected the vegetation of the Zoige Plateau.However,the spatiotemporal variations of vegetation and the relative contributions of climate change and human activities to these vegetation dynamics remain unclear.Therefore,clarifying how and why the vegetation on the Zoige Plateau changed can provide a scientific basis for the sustainable development of the region.Here,we investigate NDVI trends using the Normalized Difference Vegetation Index(NDVI)as an indicator of vegetation greenness and distinguish the relative effects of climate changes and human activities on vegetation changes by utilizing residual trend analysis and the Geodetector.We find a tendency of vegetation greening from 2001 to 2020,with significant greening accounting for 21.44%of the entire region.However,browning area expanded rapidly after 2011.Warmer temperatures are the primary driver of vegetation changes in the Zoige Plateau.Climatic variations and human activities were responsible for 65.57%and 34.43%of vegetation greening,and 39.14%and 60.86%of vegetation browning,respectively,with browning concentrated along the Yellow,Black and White Rivers.Compared to 2001-2010,the inhibitory effect of human activity and climate fluctuations on vegetation grew dramatically between 2011 and 2020. 展开更多
关键词 Vegetation change Climate change Residual trend analysis Geodetector Human activities Zoige plateau
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Changes in Spring Snow Cover over the Eastern and Western Tibetan Plateau and Their Associated Mechanism
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作者 Fangchi LIU Xiaojing JIA Wei DONG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期959-973,共15页
The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–2020.The current work investigate... The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–2020.The current work investigates the possible mechanisms accounting for these distinct TPSC changes.Our results indicate that the decrease in W_TPSC is primarily attributed to rising temperatures,while the increase in E_TPSC is closely linked to enhanced precipitation.Local circulation analysis shows that the essential system responsible for the TPSC changes is a significant anticyclonic system centered over the northwestern TP.The anomalous descending motion and adiabatic heating linked to this anticyclone leads to warmer temperatures and consequent snowmelt over the western TP.Conversely,anomalous easterly winds along the southern flank of this anticyclone serve to transport additional moisture from the North Pacific,leading to an increase in snowfall over the eastern TP.Further analysis reveals that the anomalous anticyclone is associated with an atmospheric wave pattern that originates from upstream regions.Springtime warming of the subtropical North Atlantic(NA)sea surface temperature(SST)induces an atmospheric pattern resembling a wave train that travels eastward across the Eurasian continent before reaching the TP.Furthermore,the decline in winter sea ice(SIC)over the Barents Sea exerts a persistent warming influence on the atmosphere,inducing an anomalous atmospheric circulation that propagates southeastward and strengthens the northwest TP anticyclone in spring.Additionally,an enhancement of subtropical stationary waves has resulted in significant increases in easterly moisture fluxes over the coastal areas of East Asia,which further promotes more snowfall over eastern TP. 展开更多
关键词 snow cover Tibetan Plateau long-term changes SPRING
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Trend Analysis in Standardized Precipitation Index and Standardized Anomaly Index in the Context of Climate Change in Southern Togo 被引量:6
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作者 Komlan Koudahe Adewumi J. Kayode +2 位作者 Awokola O. Samson Adekunle A. Adebola Koffi Djaman 《Atmospheric and Climate Sciences》 2017年第4期401-423,共23页
Rainfall and temperature are climatic variables mostly affected by global warming. This study aimed to investigate the temporal trend analysis in annual temperature and rainfall in the Southern Togo for the 1970-2014 ... Rainfall and temperature are climatic variables mostly affected by global warming. This study aimed to investigate the temporal trend analysis in annual temperature and rainfall in the Southern Togo for the 1970-2014 period. Daily and annual rainfall and temperature were collected from four weather stations at Atakpame, Kouma-Konda, Lome, and Tabligbo. The temperature variability was determined by the Standardized Anomaly Index (SAI) and the annual rainfall variability was determined using the Standardized Precipitation Index (SPI). The Mann-Kendall test was used for trend analysis. Mann-Kendall statistical test for the mean annual, mean annual minimum and maximum temperature from 1970 to 2014 showed significant warming trends for all stations except Kouma-Konda where mean annual maximum temperature had exhibited non significant cooling trend (P = 0.01). For Standardized Precipitation Index in the 12-month time scale, dry tendency dominates Atakpamé (55.7%) and Kouma-Konda (55.5%) while wet tendency dominates slightly Lomé (50.9%) and Tabligbo (51.4%). The Mann-Kendall test revealed an increasing trend in standardized anomaly index at all the sites, prejudicial to rainfed agriculture practiced by about 90% of Togolese crop growers. The trend analysis in the climate variables indicated a change in climate that necessitates some specific actions for resources management sustainability and conservation. 展开更多
关键词 trend Analysis MANN-KENDALL Test RAINFALL Temperature Climate change
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Climate Change: Trends and People’s Perception in Nepal 被引量:2
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作者 Rohini P. Devkota 《Journal of Environmental Protection》 2014年第4期255-265,共11页
In the context of climate change, the frequency and intensity of extreme events such as floods and droughts will increase which could put tremendous challenges in water resources management in the coming days. While s... In the context of climate change, the frequency and intensity of extreme events such as floods and droughts will increase which could put tremendous challenges in water resources management in the coming days. While scientific knowledge on climate threats and changing climate patterns are essential, it is also important to consider the impacts in relation to how the threats are perceived and handled by local people. This paper intends to assess the trend and people’s perception on temperature and precipitation. Three focus groups’ discussion and a total number of 240 households were interviewed during field visit. The collected information was scaled from the least preferred-1 to the most preferred-5 based on their preferences. The trend of mean of annual average, maximum and minimum temperature indicates that the temperature has increased significantly and precipitation intensity and magnitude are also in increasing trend in the monsoon and postmonsoon seasons which may raise the extreme flood events. These facts were verified with the people’s perception. This finding could be useful for formulation of effective flood management policy and plan in this river basin as well as very applicable for other similar areas. 展开更多
关键词 CLIMATE change trendS People’s PERCEPTION
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Long-term ocean temperature trend and marine heatwaves
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作者 Min ZHANG Yangyan CHENG +4 位作者 Gang WANG Qi SHU Chang ZHAO Yuanling ZHANG Fangli QIAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1037-1047,共11页
Marine heatwaves(MHWs)can cause irreversible damage to marine ecosystems and livelihoods.Appropriate MHW characterization remains difficult,because the choice of a sea surface temperature(SST)temporal baseline strongl... Marine heatwaves(MHWs)can cause irreversible damage to marine ecosystems and livelihoods.Appropriate MHW characterization remains difficult,because the choice of a sea surface temperature(SST)temporal baseline strongly influences MHW identification.Following a recent work suggesting that there should be a communicating baseline for long-term ocean temperature trends(LTT)and MHWs,we provided an effective and quantitative solution to calculate LTT and MHWs simultaneously by using the ensemble empirical mode decomposition(EEMD)method.The long-term nonlinear trend of SST obtained by EEMD shows superiority over the traditional linear trend in that the data extension does not alter prior results.The MHWs identified from the detrended SST data exhibited low sensitivity to the baseline choice,demonstrating the robustness of our method.We also derived the total heat exposure(THE)by combining LTT and MHWs.The THE was sensitive to the fixed-period baseline choice,with a response to increasing SST that depended on the onset time of a perpetual MHW state(identified MHW days equal to the year length).Subtropical areas,the Indian Ocean,and part of the Southern Ocean were most sensitive to the long-term global warming trend. 展开更多
关键词 marine heatwaves(MHWs) ensemble empirical mode decomposition(EEMD) long-term temperature(LTT)trend total heat exposure(THE)
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Changes of coastline and tidal flat and its implication for ecological protection under human activities: Take China’s Bohai Bay as an example
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作者 Yong Li Ming-zheng Wen +3 位作者 Heng Yu Peng Yang Fei-cui Wang Fu Wang 《China Geology》 CAS CSCD 2024年第1期26-35,共10页
The change processes and trends of shoreline and tidal flat forced by human activities are essential issues for the sustainability of coastal area,which is also of great significance for understanding coastal ecologic... The change processes and trends of shoreline and tidal flat forced by human activities are essential issues for the sustainability of coastal area,which is also of great significance for understanding coastal ecological environment changes and even global changes.Based on field measurements,combined with Linear Regression(LR)model and Inverse Distance Weighing(IDW)method,this paper presents detailed analysis on the change history and trend of the shoreline and tidal flat in Bohai Bay.The shoreline faces a high erosion chance under the action of natural factors,while the tidal flat faces a different erosion and deposition patterns in Bohai Bay due to the impact of human activities.The implication of change rule for ecological protection and recovery is also discussed.Measures should be taken to protect the coastal ecological environment.The models used in this paper show a high correlation coefficient between observed and modeling data,which means that this method can be used to predict the changing trend of shoreline and tidal flat.The research results of present study can provide scientific supports for future coastal protection and management. 展开更多
关键词 SHORELINE Tidal flat Erosion deposition patterns changing trend Ecological protection Human activity Linear regression model Inverse distance weighing method Prediction Bohai Bay
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Change Trends of Accumulated Temperature and Effects on Agricultural Production in Shenyang during Recent 58 Years 被引量:1
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作者 YANG Li-li LIU Feng-zhi JIANG Miao 《Meteorological and Environmental Research》 CAS 2011年第1期35-38,42,共5页
[Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang... [Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang, the change trends of ≥0 ℃ and ≥10 ℃ accumulated temperature in Shenyang in recent 58 years were analyzed by means of climatic statistics method, and the effects of accumulated temperature variation on agricultural production were discussed. [Result] In recent 58 years, the first day with temperature ≥0 ℃ advanced 10 d, and the last day put off slightly, while sustained days prolonged 13 d, and ≥0 ℃ accumulated temperature increased by 343 ℃·d; meanwhile, the first day with temperature ≥10 ℃ advanced 9 d, and the last day put off 8 d, while sustained days prolonged 16 d, and ≥10 ℃ accumulated temperature increased by 370 ℃·d; compared with the first 20 years, sustained days with temperature ≥0 ℃ and ≥10 ℃ prolonged 9 d in the last 20 years, and ≥0 ℃ and ≥10 ℃ accumulated temperature increased by 196 and 202 ℃·d, respectively. In addition, the increase of heat resources affected agricultural production in Shenyang. [Conclusion] The study could provide theoretical foundation for grasping heat resources variation and adjusting agriculture distribution. 展开更多
关键词 Shenyang Accumulated temperature Climatic tendency change trend China
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Long-term variations in runoff of the Syr Darya River Basin under climate change and human activities 被引量:3
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作者 Sanim BISSENBAYEVA Jilili ABUDUWAILI +1 位作者 Assel SAPAROVA Toqeer AHMED 《Journal of Arid Land》 SCIE CSCD 2021年第1期56-70,共15页
In this study,we analyzed the hydrological and meteorological data from the Syr Darya River Basin during the period of 1930–2015 to investigate variations in river runoff and the impacts of climate change and human a... In this study,we analyzed the hydrological and meteorological data from the Syr Darya River Basin during the period of 1930–2015 to investigate variations in river runoff and the impacts of climate change and human activities on river runoff.The Syr Darya River,which is supplied by snow and glacier meltwater upstream,is an important freshwater source for Central Asia,as nearly half of the population is concentrated in this area.River runoff in this arid region is sensitive to climate change and human activities.Therefore,estimation of the climatic and hydrological changes and the quantification of the impacts of climate change and human activities on river runoff are of great concern and important for regional water resources management.The long-term trends of hydrological time series from the selected 11 hydrological stations in the Syr Darya River Basin were examined by non-parametric methods,including the Pettitt change point test and Mann-Kendall trend tests.It was found that 8 out of 11 hydrological stations showed significant downward trends in river runof f.Change of river runoff variations occurred in the year around 1960.Moreover,during the study period(1930–2015),annual mean temperature,annual precipitation,and annual potential evapotranspiration in the river basin increased substantially.We employed hydrological sensitivity method to evaluate the impacts of climate change and human activities on river runoff based on precipitation and potential evapotranspiration.It was estimated that human activities accounted for over 82.6%–98.7%of the reduction in river runoff,mainly owing to water withdrawal for irrigation purpose.The observed variations in river runoff can subsequently lead to adverse ecological consequences from an ecological and regional water resources management perspective. 展开更多
关键词 river runoff variations water resources management land use/land cover changes Mann-Kendall trend test hydrological sensitivity analysis Aral Sea Central Asia
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Long-term trends in the abundance and breeding performance in Adélie penguins:the Argentine Ecosystem Monitoring Program
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作者 Mariana A.JUÁRES AnahíM.SILVESTRO +1 位作者 Brenda C.ALFONSO M.Mercedes SANTOS 《Advances in Polar Science》 CSCD 2024年第1期132-140,共9页
In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Poin... In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Point/Cabo Funes,South Shetland Islands;and Esperanza/Hope Bay in the Antarctic Peninsula)from 1995/96 to 2022/23.Using yearly count data of breeding groups selected,we observed a decline in the number of breeding pairs and chicks in crèche at all colonies studied.However,the magnitude of change was higher at Stranger Point than that in the remaining colonies.Moreover,the index of breeding success,which was calculated as the ratio of chicks in crèche to breeding pairs,exhibited no apparent trend throughout the study period.However,it displayed greater variability at Martin Point compared to the other two colonies under investigation.Although the number of chicks in crèche of Adélie penguins showed a declining pattern,the average breeding performance was similar to that reported in gentoo penguin colonies,specifically,those undergoing a population increase(even in sympatric colonies facing similar local conditions).Consequently,it is plausible to assume a reduction of the over-winter survival as a likely cause of the declining trend observed,at least in the Stranger Point and Esperanza colonies.However,we cannot rule out local effects during the breeding season affecting the Adélie population of Martin Point. 展开更多
关键词 long-term monitoring Adélie penguin breeding pairs chicks crèched breeding success population trends
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Long-term chorioretinal changes following strabismus surgery——possible occult needle penetration 被引量:1
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作者 Victor M.Villegas Stephen G.Schwartz +1 位作者 Craig A.McKeown Harry W.Flynn Jr 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第3期518-519,共2页
Dear Editor,cleral penetration during strabismus surgery was k3 first reported over 50 years ago[1].Early manuscripts reported the incidence of this complication around 10%[1].However,more recent studies suggest that ... Dear Editor,cleral penetration during strabismus surgery was k3 first reported over 50 years ago[1].Early manuscripts reported the incidence of this complication around 10%[1].However,more recent studies suggest that this rate may have decreased[2-3]. 展开更多
关键词 IRB POSSIBLE OCCULT needle penetration long-term chorioretinal changeS FOLLOWING STRABISMUS surgery
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The Changes in Guilin Paddy Soil Organic Matter and Rice Yield under Long-Term Fertilization 被引量:2
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作者 Qiuliang YU Zheng TANG +3 位作者 Zhongfang LI Chunlan CHEN Xiaoxian TANG Yanli LIN 《Asian Agricultural Research》 2016年第3期54-57,共4页
Rational fertilization is an important measure to increase crop yield and soil fertility. Through analysis,this paper aims to master the change characteristics of soil organic matter and rice yield under different fer... Rational fertilization is an important measure to increase crop yield and soil fertility. Through analysis,this paper aims to master the change characteristics of soil organic matter and rice yield under different fertilizer treatments,in order to provide an important reference for the sustainable use of soil and effective fertilization. Long-term( 19 years) rice crop rotation experiments in waterloggogenic paddy soil were conducted to investigate the change trend of crop grain yield and soil organic matter with time,reveal the dynamic characteristics and relationship between main fertility factors and crop yields using comparative analysis at three sites with conventional fertilization and non-fertilization in Guilin. The results showed that compared with previous years,the rice yield increased by 53% under the fertilization treatment and degreased by 66% under the control. Over the years,the average soil organic matter( SOM) content under fertilization treatment was 23% higher than under CK treatment. This indicates that chemical fertilizer and organic manure application can increase the rice yield and soil organic matter,and high rice yield can be attributed to the SOM increase. 展开更多
关键词 long-term fertilization Waterloggogenic PADDY SOIL SOIL organic matter(SOM) Yield change
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A comprehensive study of long-term skeletal changes after spinal cord injury in adult rats 被引量:1
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作者 Tiao Lin Wei Tong +11 位作者 Abhishek Chandra Shao-Yun Hsu Haoruo Jia Ji Zhu Wei-Ju Tseng Michael A Levine Yejia Zhang Shi-Gui Yan X Sherry Liu Dongming Sun Wise Young Ling Qin 《Bone Research》 SCIE CAS CSCD 2015年第3期164-172,共9页
Spinal cord injury(SCI)-induced bone loss represents the most severe osteoporosis with no effective treatment.Past animal studies have focused primarily on long bones at the acute stage using adolescent rodents. To ... Spinal cord injury(SCI)-induced bone loss represents the most severe osteoporosis with no effective treatment.Past animal studies have focused primarily on long bones at the acute stage using adolescent rodents. To mimic chronic SCI in human patients, we performed a comprehensive analysis of long-term structural and mechanical changes in axial and appendicular bones in adult rats after SCI. In this experiment, 4-month-old Fischer 344 male rats received a clinically relevant T13 contusion injury. Sixteen weeks later, sublesional femurs, tibiae,and L4 vertebrae, supralesional humeri, and blood were collected from these rats and additional non-surgery rats for micro-computed tomography(m CT), micro-finite element, histology, and serum biochemical analyses.At trabecular sites, extreme losses of bone structure and mechanical competence were detected in the metaphysis of sublesional long bones after SCI, while the subchondral part of the same bones showed much milder damage. Marked reductions in bone mass and strength were also observed in sublesional L4 vertebrae but not in supralesional humeri. At cortical sites, SCI induced structural and strength damage in both sub- and supralesional long bones. These changes were accompanied by diminished osteoblast number and activity and increased osteoclast number and activity. Taken together, our study revealed site-specific effects of SCI on bone and demonstrated sustained inhibition of bone formation and elevation of bone resorption at the chronic stage of SCI. 展开更多
关键词 SCI BONE A comprehensive study of long-term skeletal changes after spinal cord injury in adult rats
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The burden and long-term trends of breast cancer by different menopausal status in China
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作者 Shaoyuan Lei Rongshou Zheng +1 位作者 Siwei Zhang Wenqiang Wei 《Journal of the National Cancer Center》 2024年第4期326-334,共9页
Background: The burden of breast cancer in women of different menopausal status has not been assessed in China previously. We aim to evaluate and project the burden of breast cancer in different menopausal status in C... Background: The burden of breast cancer in women of different menopausal status has not been assessed in China previously. We aim to evaluate and project the burden of breast cancer in different menopausal status in China. Methods: The incidence and mortality of breast cancer were estimated using the data of 554 cancer registries in 2017 and the trends of incidence and mortality of 112 cancer registries from 2010 to 2017. Data from 22 continued cancer registries from 2000 to 2017 were applied for long-term trend projection to 2030 using the Bayesian age- period-cohort model. Menopausal status was stratified by age, with premenopause defined as chronological age < 45 years, perimenopause defined as 45-54 years, and postmenopause defined as ≥ 55 years. Results: Approximately 352,300 incident cases and 74,200 deaths of breast cancer occurred in China in 2020, contributing to 2.6 million disability-adjusted life years (DALYs). Perimenopausal women had the highest inci- dence, prevalence, and DALYs rates, with the rates being 100.3 per 100,000, 819.2 per 100,000 and 723.1 per 100,000 persons. While postmenopausal women had the highest mortality rates (25.5 per 100,000 persons). From 2000 to 2017, the largest increase in incidence and mortality for breast cancer was observed in postmenopausal women with an average annual percentage change (AAPC) of 5.6% and 2.94%. The number of breast cancer cases and deaths will increase to 452,000 and 98,800 in 2030, resulting in 3.2 million DALYs. Conclusions: The burden of breast cancer is rapidly increasing in China and varies among different menopausal status. Specific prevention and control strategies for women in different menopausal status will be more helpful in reducing the rapidly growing trends of breast cancer. 展开更多
关键词 Breast cancer Menopausal status long-term trends China
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Future Extremes Temperature: Trends and Changes Assessment over the Mono River Basin, Togo (West Africa)
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作者 Lawin Agnidé Emmanuel Lamboni Batablinlè +1 位作者 Manirakiza Célestin Kamou Hodabalo 《Journal of Water Resource and Protection》 2019年第1期82-98,共17页
This study assessed the extreme temperatures trends and changes over Mono River Basin under the highest greenhouse gas emission scenario RCP8.5. Simulations of five (5) regional climate models (RCMs) provided by Afric... This study assessed the extreme temperatures trends and changes over Mono River Basin under the highest greenhouse gas emission scenario RCP8.5. Simulations of five (5) regional climate models (RCMs) provided by Africa-CORDEX program were selected from the eighth (8) considered. Future trends in temperature percentiles, including extremes, are used to assess changes in the distribution of daily temperature over Mono Basin in Togo. Changes of temperature and Extreme low (high) temperatures from the baseline period 1961-2010 were computed for future (2051-2100). This analysis reveals that in the north of the basin, for the positive trends, the maximum is 0.82°C·year-1 given by model MPI-ESM2 at Tchamba while the strongest negative change is 0.26°C·year-1 given by model MIROC at Sotouboua. In the south of the basin, the strongest negative trend is of 0.03°C·year-1 given by model (A) CNRM-CMA5. The maximum ones of the trends for models-mean are all positive except at Anié. Higher percentiles of minimum and maximum temperature will increase at a greater rate than the lower percentiles during dry and rainy seasons (with differences more pronounced for maximum values) over the north. Concerning future changes, almost all the RCMs predicted an increase of maximum and minimum temperatures over most parts of the Mono Basin, particularly in the north. Finally, results predicted an increase of TX90P (TX10P) and TN90P (TN10P) from 10% to 45% (13% to 40%) and 0% to 35% (12% Mean value), respectively over Mono Basin. 展开更多
关键词 FUTURE Extreme Temperatures trendS changeS MONO River Basin TOGO
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