Changing Trends Research Articles

Understanding the Baltic Dry Index (BDI): an explainable decomposition approach

ABSTRACT The Baltic Dry Index (BDI) is a crucial indicator of the dry bulk freight market, offering insights into the shipping industry’s health and activity levels. In this study, we introduce an explainable decomposition framework to unveil the underlying mechanisms of BDI dynamics. Utilizing historical data from 1 November 1999, to 5 March 2024, we decompose BDI into trends, seasonal fluctuations, and externally derived influences. Our experiments have identified the magnitude of trend changes from major global events over the past two decades. Intriguingly, we find that advancements in industry and technology contribute significantly to upward trends in BDI. We also explore BDI’s seasonality, identifying distinct cyclical patterns within a year, including the Christmas and Chinese New Year effects, and more interestingly, a trough in late June due to the receding in shipping demand for the three major bulk. Our findings further offer valuable insights into understanding BDI fluctuations, aiding decision-making processes in the maritime freight market. We find that Natural Gas and the Dollar Index are potent signals for BDI one week to one month ahead, while the NASDAQ 100 Index emerges as a leading indicator for longer forecasting horizons.

ЕКСПОРТ СІЛЬСЬКОГОСПОДАРСЬКОЇ ПРОДУКЦІЇ В УМОВАХ ВІЙНИ: РЕГІОНАЛЬНІ АСПЕКТИ

Introduction. Agriculture is one of the important export-oriented sectors of the economy of Ukraine. In the conditions of constant structural changes in the economy under the influence of economic and political instability, it is expedient to investigate the place of agricultural products in commodity exports of Ukraine, as well as in the formation of the export potential of the regions. It is urgent to identify the regional peculiarities of the export of agricultural products, to determine the specialization of the regions. The purpose of the article. The purpose of the study is to analyze the regional structure of agricultural exports, to determine the place of agriculture in the commodity exports of the regions, to point out the changes in the export structure caused by the full-scale war. Metods. The conducted research was based on the analysis of statistical data on export volumes in Ukraine and in the regions. Conclusions about regional aspects of export of agricultural products are made on the basis of data systematization, scientific abstraction and methods of comparative analysis. Results. The current trends in the export of agricultural products of Ukraine were studied. The share of regions in the formation of commodity exports of agricultural products of Ukraine has been established. The changes in the export structure (in terms of main product groups and subgroups) that took place under the influence of a full-scale war were determined. The share of agricultural products in the formation of the commodity structure of the regions' exports has been determined, and the export specialization of the regions (within agricultural products) has been determined. The main exporters, problems and promising directions of export development in the regions are indicated. It has been established that in certain regions of Ukraine, agricultural export plays a key role in the formation of the region's export potential. Conclusions. Based on the results of the conducted research, conclusions were made about the specialization of regions by types of agricultural products, the peculiarities and changes in trends regarding the export of agricultural products in the regions were indicated.

Temporal, Spatial Characteristics and Prediction of Precipitation in Guangzhou Based on the SARIMA Model

This article obtains nearly 18 years of precipitation data for Guangzhou from the National Centers for Environmental Information (NCEI) under the National Oceanic and Atmospheric Administration (NOAA) and conducts visualization analysis and modeling predictions using R software.Using the classic SARIMA model (the ARIMA model with seasonal components) as well as regression and residual ARIMA models to build and simulate the precipitation series.We also used Basic-bootstrap prediction, which involves resampling the residuals of the fitted model with replacement, using historical values to predict the future and obtain a model parameter, as well as Full-bootstrap prediction (which assumes that the residuals have uncertainty and that the estimated model coefficients themselves also have uncertainty).Therefore, not only are reasonable model residuals obtained through the bootstrap method, but multiple model parameters are also derived from this method to determine more reasonable model parameters, which are then used to forecast the next 12 periods for the fitted model. Comparing the results of the four prediction models, the Full-bootstrap model under the regression model showed the best predictive performance. The study found that there is no significant trend in precipitation changes over time, but short-term fluctuations still exist. Although some extreme values appeared, they remain within a predictable range.Therefore, the relevant city government departments prone to extreme rainfall can make reasonable adjustments to drainage facilities based on local precipitation forecasts

From Valletta to Faro: Archaeological Heritage and Communities

The article discusses the changing trends in archaeological heritage conservation – from expertise-based heritage protection to the “democratisation of heritage”. This process is well represented by the Amersfoort Agenda, adopted by the The Europae Archaeologiae Consilium (EAC) in 2014, which seeks to integrate the principles of the Faro Convention into the practice of archaeological heritage protection developed by the Valletta Convention. More generalised heritage conservation processes and changes in public administration policies that promote participatory (interactive) governance also contribute to a stronger role for society in decision-making. It is in this aspect – the relationship between archaeology and society – that the paper presents contemporary trends in archaeological heritage conservation, as well as insights into local communities’ attitudes towards archaeological heritage in Lithuania.

ادب، معاشرہ ، سیاست اور کشور ناہید کے افکار کا جائزہ

The relationship between politics and literature is quite old, and many Urdu writers have tried to exercise their right to express their theories of literature by raising their voice against the constraints of time. Notable names include Bashir Badr, Nida Fazli, Javed Akhtar, Rahat Indori, Mustafa Zaidi, Manzar Rana, Shakil Badayuni, Arshad Nishat, and Rasa Chughtai. While almost everyone expresses their feelings about the current situations in a poetic manner, it is difficult to find someone like Kishwar. Naheed who has expressed his ideas in literary form using verbal structures. Such personalities are those who not only fearlessly wrote their literary theories in the face of changing trends but also their poetic and prose works embody their concepts. In the context of Kiswar Naheed's book "Dairon Mein Pheli Lakeer" (The Line Spread in Circles), the role of a writer in representing the style of a writer will be expressed through the themes of his poetry.

Development of Fractional Vegetation Cover Change and Driving Forces in the Min River Basin on the Eastern Margin of the Tibetan Plateau

Fractional vegetation cover (FVC) is an important indicator of regional ecological environment change, and quantitative research on the spatial and temporal distribution of FVC and the trend of change is of great significance to the monitoring, evaluation, protection, and restoration of regional ecology. This study estimates the FVC of the eastern Tibetan Plateau margin from 2000 to 2020 using the image element dichotomous model based on the Google Earth Engine platform using MODIS-NDVI images. It also investigates the temporal and spatial changes of the FVC in this region and its drivers using the Theil–Sen and Mann–Kendall trend tests, spatial autocorrelation analysis, geodetector, and machine learning approaches impact. The results of this study indicated a generally erratic rising tendency, with the Min River Basin (MRB) near the eastern tip of the Tibetan Plateau having an annual average FVC of 0.67 and an annual growth rate of 0.16%. The percentage of places with better vegetation reached 60.37%. The regional FVC showed significant positive spatial autocorrelation and was clustered. Driver analyses showed that soil type, DEM, temperature, potential evapotranspiration, and land use type were the main drivers influencing FVC on the eastern margin of the Tibetan Plateau. In addition, the random forest (RF) model outperformed the support vector machine (SVM), backpropagation neural network (BP), and long short-term memory network (LSTM) in FVC regression fitting. In summary, this study shows that the overall FVC in the eastern margin of the Tibetan Plateau is on an upward trend, and the regional ecological environment has improved significantly over the past two decades.

Impact of a new case-based payment scheme on volume distribution across public hospitals in Zhejiang, China: does ‘Same disease, same price’ matter

BackgroundWith the implementation of the hierarchical medical system (HMS) in China, Zhejiang Province introduced an innovative payment scheme called “payment method by disease types with point counting”. This scheme was initially adopted in Jinhua in July 2017, and was later integrated with the “same disease, same price” policy in Hangzhou in January 2020. This study aimed to investigate the impact of these reforms on the distribution of health service volume.MethodsData were obtained from 104 hospitals, including 12 tertiary and 14 secondary hospitals from each of four regions: Jinhua (intervention) vs. Taizhou (control), and Hangzhou (intervention) vs. Ningbo (control). A total of 3848 observation points were examined using two sets of controlled interrupted time series analyses to assess the effects of this new case-based payment, without and with “same disease, same price”, on the proportion of discharges, total medical revenue and hospitalization revenue. The Herfindahl–Hirschman Index (HHI) were analyzed to evaluate changes in market competition.ResultsFollowing the introduction of the new case-based payment without “same disease, same price”, secondary hospitals in Jinhua experienced a significant decline in the proportion of discharges (β6 = -0.1074, p = 0.047), total medical revenue (β6 = -0.0729, p = 0.026), and hospitalization revenue (β6 = -0.1062, p = 0.037) compared to those in Taizhou, while tertiary hospitals showed a non-significant increase. After incorporating “same disease, same price”, the proportion of discharges (β6 = 0.2015, p = 0.031), total medical revenue (β6 = 0.1101, p = 0.041) and hospitalization revenue (β6 = 0.1248, p = 0.032) in Hangzhou’s secondary hospitals increased compared with Ningbo’s, yet the differences in both the level and trend changes between tertiary hospitals in the two cities were not statistically significant. The HHI in Jinhua (β7 = 0.0011, p = 0.043) presented an upward trend during the pilot period of the case-based payment, while the HHI in Hangzhou (β6 = -0.0234, p = 0.021) decreased immediately after the introduction of “same disease, same price”.ConclusionThis new case-based payment scheme may worsen the disproportionate distribution of service volume across hospitals of different levels. While “same disease, same price” shows potential benefits, further evidence is needed to assess its effectiveness in promoting HMS. Policymakers should consider hospital interests in payment design and address unintended strategic behaviors.

Spatiotemporal Variation and Driving Analysis of Net Primary Productivity of Vegetation in Southern Part of Taihang Mountain, China

The net primary productivity of vegetation (NPP) is an important index to evaluate the carbon sequestration capacity of vegetation and land use change. Using MOD17N3HGF NPP data, climate data and night-time light data from 2000 to 2020, this study explored the relationship between NPP and urban expansion, land use and climate change in the Southern Part of Taihang Mountain through brightness gradient method, trend analysis, partial correlation analysis and contribution analysis. It aims to provide information support for urban and rural planning and ecological management in this region. Key findings include: Over the past 20 years, NPP in mountain areas has shown an overall fluctuating upward trend, with an "N" pattern related to altitude. The human activity area expanded by 9.9%, with expansion of highly active areas holding back NPP growth and moderately active areas contributing to it. The trend of climate change is gradually warming and wetting, and the correlation between precipitation and NPP is strong, while the correlation between temperature and NPP is weak. Compared with human activities (19.9%), precipitation was the main driver of NPP change, contributing significantly up to 79.5%. In the past 20 years, the ecological quality of the south Taihang Mountain region has improved significantly and actively responded to climate change, but human activities have led to spatial and temporal ecological differences.

Temporal trends of community and climate changes in the anthropocene: 21-year dynamics of four major functional groups in a rocky intertidal habitat along the Pacific coast of Japan

The influence of climate change on marine organism abundance has rarely been assessed (1) at the functional-group level; (2) simultaneously in major functional groups within the same ecosystem; (3) for >10 years; and (4) at metapopulation/community scales. A study simultaneously addressing these gaps would greatly enhance our understanding of the influence of climate change on marine ecosystems. Here, we analyzed 21 years of abundance data at the functional-group and species levels on a regional scale for four major functional groups (benthic algae, sessile animals, herbivorous benthos, and carnivorous benthos) in a rocky intertidal habitat along the northeastern Pacific coast of Japan. We aimed to examine the 21-year trends in regional abundance at both functional-group and species levels, plus their driving mechanisms and their dependence on species properties (thermal niche, calcification status, and vertical niche). Significant temporal trends in abundance were detected at functional-group levels for benthic algae (increasing) and herbivores and carnivores (both decreasing); they followed the temporal population trends of the dominant species. At species level, the metapopulation size of 12 of 31 species were increasing and 4 of those were decreasing, depending on the thermal niche and species calcification status. At both functional-group and species levels, temporal trends in abundance are caused by the direct or indirect influence of warming and ocean acidification. Comparing these results with community responses to marine heat waves in the same study area offered two implications: (1) long-term ecosystem changes associated with global warming will be unpredictable from the community response to marine heat waves, possibly owing to a lack of knowledge of the influence of calcifying status on species’ responses to climate change; and (2) thermal niches contribute greatly to predictions of the influence of warming on population size, regardless of the time scale.

Customer Relationship Management initiatives in Pharmaceutical Industry in India: The Newer and emerging trends of CRM & their impact

Pharmaceutical industry in India is one of the fastest growing industries in the country today, growing with an average CGAR of 8.5% with an approx. market size of approx. 2 trillion. The relevance of the Indian Pharmaceutical industry can be measured by the fact that today India is considered as the Pharmacy of the World. However, the industry is now experiencing a rapid change because of the changing scenario in the field of Pharmaceutical Marketing. The dependence of marketing strategies on Key Opinion leaders or decision maker Doctors had given rise to newer trends of marketing strategies to win over the confidence of KOLs. In the current scenario the most important tool which Pharma companies use to retain their KOLs is Customer Relationship management initiatives. Although Indian Pharmaceutical companies are practicing these CRM based marketing since last 2-3 decades or so, there seems a huge paradigm shift from traditional mode of customer relationship management (CRM) to the highly advanced and intuitive means of CRM initiatives, which are in practice now a days. This paradigm shift which was happening at a steady pace, have been hastened due to the sudden emergence of Covid-19. This paper tries to explore these changing trends of CRM marketing strategies adapted by the Indian Pharmaceutical industry, in the field of pharmaceutical marketing in India & the extent of their impact on medical practitioners in India, for whom they are designed.

Investigation of spatiotemporal changes of drought trend in Indian River Basin system over the century

Investigation of spatiotemporal changes of drought trend in Indian River Basin system over the century

Impact of policy changes expanding access to direct acting antivirals on hepatitis C virus-related hospitalizations in people with HIV: a population-based study

Abstract Background The burden of hepatitis C virus (HCV)-related hospitalizations is substantial, particularly among people with HIV and HCV (HIV/HCV). In Ontario, Canada, use of direct-acting antivirals (DAAs) increased following policies removing fibrosis stage restrictions and the approval of pan-genotypic agents in 2017 and 2018, respectively. We examined the impact of expanded DAA access on HCV-related hospitalizations in people with HIV. Methods We conducted a population-based study using administrative databases between April 2003, and December 2022. We used segmented negative binomial regression to examine changes in level and trend of quarterly HCV-related hospitalization rates in people with HIV following the policy changes and compared predicted rates in the absence of expanded DAA access with observed rates during this period. Results We identified 2943 HCV-related hospitalizations among people with HIV during our study period. Rates of HCV-related hospitalizations were substantially higher among people with HIV than individuals without HIV. In the post-intervention period, there was an immediate level increase in the rate of HCV-related hospitalizations (rate ratio [RR]1.23; 95% confidence interval [CI], 1.18 to 1.29) followed by a decrease in trend (RR 0.94 per quarter; 95% CI, 0.93 to 0.94). We estimated that expanding DAA access was associated with 192 fewer hospitalizations in people with HIV between 2018 and 2022. Discussion Policies expanding DAA access have reduced HCV-related hospitalizations in people with HIV. However, rates were higher relative to those in people without HIV. Further research is needed to identify and address disparities in clinical outcomes among people with HIV and HCV.

Enhancing Maize Production Through Timely Nutrient Supply: The Role of Foliar Fertiliser Application

Maize, regarded as a staple economic crop, attracts special global attention with the aim to enhance its production. Foliar fertilisation offers a complementary method to traditional soil fertilisation amongst resource-limited agricultural systems, providing a more efficient solution to nutrient deficiencies, especially in suboptimal soil conditions. This study aimed to analyse foliar fertiliser formulation research directions and their application in maize production. A literature search was conducted in the Web of Science (WoS) database. Bibliometric analyses were performed using the VOSviewer software (version 1.6.17). The changes in the publication trends of documents were tested using the Mann–Kendall test. The production effects of foliar fertilisation were independently synthesised. The results showed a strong positive increase in publication trends regarding maize foliar fertilisation (R2 = 0.7842). The predominant nutrients that affected maize production were nitrogen, phosphorous, potassium, zinc, iron, and manganese. The timely foliar application of nutrients corrected deficiencies and/or sustained nutrient supply under several abiotic stresses. Foliar application at critical growth stages like flowering and grain filling boosted carbohydrate and protein content, lipid levels, kernel size, mineral content, and the weight of the maize grain. This review identified important research gaps, namely genotype-specific responses, interactions with other agronomic practices, and long-term environmental effects.

The Functional Fitness of the Community Dwelling Older Adults in Shan Dong of Mainland China in Comparison with the Population in Hong Kong

Purpose: To compare the functional fitness (FF) of the community dwelling older adults in Shan Dong (SD) of mainland China with their peers from Hong Kong (HK). Methods: 1887 older adults living in SD were assessed with the Senior Fitness Test (SFT). One-sample t-tests were used to determine age group differences in each FF component between the SD and HK populations. Results: Compared with their HK peers, SD adults showed better performance in the task of 30s arm curl, but lower ability in the 30s chair stand, back scratch, chair sit & reach, and 8 ft up & go across all age groups. In the 2 min test, SD males demonstrated lower capacity at 75-79 years old, females exhibited higher and lower ability at 65-69, 70-74 and 80-84 years old, respectively. Additionally, higher BMI was observed in SD males at 65-69 years old and in females at 65-69, 70-74 and 75-79 years old. The changing trends of SD-HK disparities with aging varied between genders and different FF parameters, and notably, the disadvantage in motor abilities of the SD old females tended to increase with age, which resulted in relative larger gaps at 80-84 years old. Conclusions: There are great disparities in functional fitness between the older adults of SD and HK. Age-stratified and gender-specific interventions focusing on the motor abilities of lower extremity strength, upper and lower body flexibility and agility and balance control should be established for the SD old residents, especially for females.

Cannabis use characteristics and associations with problematic use outcomes, quitting-related factors, and mental health among US young adults

ObjectiveGiven the changes in trends of cannabis use (e.g., product types), this study examined latent classes of young adult use and associations with use-related outcomes.MethodsWe analyzed 2023 survey data among 4,031 US young adults (Mage=26.29, 59.4% female, 19.0% Hispanic, 13.5% Black, 13.6% Asian). Among those reporting past-month use (48.8%), latent class analysis (LCA) indicators included: days used (1–5; 6–20; 21–30), use/day (1; 2–4; ≥5), and type usually used (herb/flower; edibles; oils/vape; concentrates/other). Multivariable regressions examined class in relation to problematic use, quitting-related factors, and mental health, controlling for sociodemographics and state non-medical cannabis laws.ResultsLCA identified 4 classes of cannabis use frequency and types used: ‘infrequent-herb/edibles’ (41.4%), ‘frequent-herb’ (16.8%), ‘moderate-herb’ (28.0%), and ‘moderate-oil/other’ (13.8%). In multivariable analyses (referent group: ‘moderate-herb’ class), ‘frequent-herb’ reported less problematic use (B=-0.18, 95%CI=-0.30, -0.07), while ‘moderate-oil/other’ reported greater (B = 0.39, 95%CI = 0.27, 0.51). ‘Infrequent-herb/edibles’ had lower odds of driving post-use of cannabis (aOR = 0.28, 95%CI = 0.22, 0.37) and cannabis/alcohol (aOR = 0.52, 95%CI = 0.35, 0.76), whereas ‘frequent-herb’ (aOR = 1.52, 95%CI = 1.02, 2.28) and ‘moderate-oil/other’ (aOR = 3.98, 95%CI = 2.72, 5.82) reported greater odds of driving post-cannabis/alcohol use. ‘Moderate-oil/other’ reported higher quitting importance (B = 0.59, 95%CI = 0.17, 1.01), while ‘frequent-herb’ reported lower (B=-0.33, 95%CI=-0.99, -0.18). ‘Infrequent-herb/edibles’ reported higher quitting confidence (B = 0.56, 95%CI = 0.20, 0.92), whereas ‘frequent-herb’ (B=-1.01, 95%CI=-1.45, -0.57) and ‘moderate-oil/other’ (B=-1.27, 95%CI=-1.74, -0.81) reported lower. ‘Infrequent-herb/edibles’ reported fewer mental health symptoms (B=-0.55, 95%CI=-0.93, -0.17), while ‘moderate-oil/other’ reported more (B = 1.03, 95%CI = 0.53, 1.52).ConclusionsPreventing frequent and moderate use of cannabis, particularly of oils/concentrates, is crucial given the potential negative implications for problematic use, quitting, and mental health.

The biomechanical effects of treating double-segment lumbar degenerative diseases with unilateral fixation through interlaminar fenestration interbody fusion surgery: a three-dimensional finite element study

BackgroundTransforaminal lumbar interbody fusion (TLIF) surgery has become increasingly popular in the surgical treatment of lumbar degenerative diseases. The optimal structure for stable double-segment fixation remains unclear.ObjectiveTo compare the biomechanical changes of unilateral fixation versus bilateral fixation in patients with lumbar degeneration undergoing double-segment TLIF surgery, and to explore the stability and feasibility of unilateral double-segment fixation.MethodsA three-dimensional finite element model of L3-5 was established based on CT data from a recruited young male volunteer, and the model was validated to have reasonable predictive capability. Surgical procedures were simulated by adjusting bony structures to create models of unilateral and bilateral fixation for double-segment TLIF. Under a pure moment of 10 Nm, range of motion (ROM), extension, lateral bending, axial rotation movements, as well as stresses on interbody fusion devices, internal fixation, and endplates were recorded and compared.ResultsUnilateral fixation was fixed on the left side, with both groups performing flexion, extension, left lateral flexion, right lateral flexion, left rotation, and right rotation movements. All reconstructed conditions showed decreased motion from L3 to L5. Unilateral fixation had greater lumbar spine range of motion (ROM) in all directions compared to bilateral fixation. The greatest difference between the two occurred during right lateral flexion at the L3-4 segment, measuring 1.78°. During right lateral flexion at the L4-5 segment, the largest difference was 2.29°. Regarding stress on the fusion devices, unilateral fixation models exhibited higher stresses than bilateral fixation models, but no significant differences in stability were found. Terminal plate stress in unilateral posterior fixation was higher during flexion than in the bilateral model, showing a similar trend in stress changes. No significant difference was seen in internal fixation stress between the two groups during two-segment fusion, with the posterior internal fixation stress in unilateral fixation being 1.7 times higher during flexion and 1.9 times higher during left bending compared to bilateral fixation.ConclusionUnilateral fixation in two-segment transforaminal lumbar interbody fusion (TLIF) surgery can increase stability compared to bilateral fixation, with no significant differences observed between the two models. Unilateral two-segment fixation allows for greater lumbar spine mobility than bilateral fixation, albeit with a slight increase in stress on the posterior fixation and fusion devices under the unilateral fixation mode. This provides some biomechanical evidence for selecting surgical approaches for elderly patients who cannot tolerate long surgeries, suggesting that two-segment unilateral fixation may be advisable.Clinical trial numberNot applicable.

Trend analysis and change point detection in precipitation time series over the Eastern Province of Rwanda during 1981–2021

This study examines trends and change points in agroclimatic variables at 56 meteorological stations’ locations and region levels in Rwanda’s Eastern Province from 1981 to 2021. We used the Mann–Kendall and Regional Kendall tests, along with Sen’s Slope and Sequential Mann–Kendall Rank Statistic tests, to analyse six key agricultural indicators: seasonal rainfall totals, number of rainy days, rainfall intensity (light, moderate, heavy), onset and cessation dates, and season duration. In the March to May (MAM) season, 39 out of 56 stations recorded a decreasing rainfall trend, with significant trends observed at eight stations in the south. Conversely, 17 stations showed increasing trends, with only one in the north being significant. Regionally, the trend was a non-significant decrease. In the September to December (SOND) season, 31 stations (one significant) experienced decreasing rainfall trends. Among the 25 stations showing increasing trends, only one was significant. The regional trend indicates a non-significant increase. Onset days showed a decreasing trend at 41 stations (12 significant) in both MAM and SOND and a significant regional trend in SOND. Season duration increased at 43 stations in MAM (five significant) and 48 stations in SOND (six significant), with the regional trend being significant only in SOND. Heavy rainy days indicate a significantly regional decreasing trend in MAM. The change point of most stations with decreasing and increasing trends occurred between 2000–2020 and 1980–2000, respectively. These fluctuations have affected agricultural practices and led to crop failures, emphasizing the region’s need for better climate information services and adaptation strategies.

Revealing the rural multifunctionality declining and its causes in depopulated regions of Northeast China: a case study of Heilongjiang Province

As the main form of global rural decline, the impact of rural population loss on the overall level and trend of rural multifunction is still unclear. Thus, it is crucial to reveal the characteristics and influencing factors of rural multifunction changes in depopulation areas which is important to actively deal with depopulation and promote sustainable development in rural areas. Based on an evaluation of rural multifunctionality from 2000 to 2020, the spatial statistical analysis method and a geographical model were used to reveal the declining characteristics of rural multifunction in the depopulation area, as well as the effects of the influencing factors in the whole region and under various population size areas. The results show that demographic changes had a significant impact on rural multifunction development. Compared to areas with population growth, the weakening of rural multifunctionality was more likely to occur in counties with depopulation. The negative impact of population shrinkage on rural multifunction development was shown in our results as an inverted “U” shape. In the process of demographic shrinkage, the dominant factors affecting rural multifunctionality in the whole region tended to be diversified, but the population urbanization rate was always the main factor. Among regions with different population sizes, natural factors played important roles in the development of rural multifunction, and depopulation enhanced the impact of economic factors. The interaction effect of natural, social, and economic factors was stronger than that of a single factor in rural multifunction. In the process of depopulation, the interaction effect was more and more polarized. The interaction effect of economic and natural factors enhanced, but which was the most stable in mid-population-size areas. Thus, to alleviate rural decline and realize rural revitalization, the trend of demographic change should be given attention to keep a moderate population size, as well as we should actively deal with the impact of population shrinkage on rural multifunction according to different stages of population shrinkage.

Spatio-temporal Evolution Patterns and Spatial Differentiation Attribution of Ecological Quality in Guiyang from 1991 to 2020

Exploring the trend of long time-series ecological quality evolution and spatial differentiation of influencing factors in Guiyang is of great significance for realizing regional ecological protection and high-quality development strategies. Based on the 7-period Landsat remote sensing images from 1991 to 2020, the remote sensing ecological index （RSEI） of Guiyang from 1991 to 2020 was calculated using the GEE remote sensing big data platform, and a geodetector, Hurst index, and coefficient of variation with different random sampling quantities and classification strategies were used to analyze the evolutionary pattern of ecological quality, change trends, and spatial differentiation influencing factors. The results showed that ① The ecological quality of Guiyang in the past 30 years was mainly medium and good, showing a wave-like pattern of change, with the highest and lowest values occurring in 2020 （mean value 0.58） and 2010 （mean value 0.47）, respectively, and the overall trend of the RSEI in the past ten years was good, with a spatial trend of decreasing distribution from the northeast to the southwest. ② The domain of values of the coefficient of variation for the RSEI in Guiyang was in the range of （0-2）, of which 46.61% of the area was in high fluctuation change, and the overall volatility of the RSEI was large； the mean value of the Hurst index was 0.59, and the area greater than 0.5 accounted for 73.98%, most of which showed weak persistence, and the future trend of change was the same as that of the past 30 years. ③ Different classification methods and random samples affect the q-value results of the geodetector, but the trend of the size ordering of the explanatory power of different factors was generally consistent. Land use, nighttime lighting index, slope, and population density indicators had stronger explanatory power for RSEI spatial differentiation； factor interaction detection was two-factor enhancement and nonlinear enhancement； and the interaction between land use and other factors was most favorable for explaining RSEI spatial differentiation.

Quantitative Analysis of the Drivers of the Spatio-temporal Evolution of Vegetation NPP in the Beijing-Tianjin-Hebei Ecological Barrier Area

The Taihangshan-Yanshan Region is an important ecological barrier area in Beijing-Tianjin-Hebei, and it is of great importance to investigate the spatial distribution pattern and driving mechanism of net primary productivity （NPP） of vegetation for ecological restoration. The MOD17A3HGF.061 NPP dataset was obtained using the Google earth engine（GEE）, and Sen trend, coefficient of variation, partial correlation, complex correlation, and residual analysis were applied to investigate the spatial and temporal patterns of vegetation NPP in the study area and to quantitatively isolate the relative contributions of climate change and human activities. The results showed that： ① The vegetation NPP in the study area showed an overall increasing trend from 2003 to 2021, with a rate of（C-based）2.57 g·（m2·a）-1 and the distribution characteristics of "low in the surroundings and high in the middle" in the Taihangshan area, "high in the north and low in the south" in the Yanshan area, and "low in the north and low in the south" in the Yanshan area. At the same time, the spatial distribution characteristics of "low around and high in the middle" in the Taihangshan area and "high in the north and low in the south" in the Yanshan area were shown. Nearly 70% of the regions had medium or low volatility of vegetation NPP, and 80% of the regions had the opposite trend of future changes. ② The vast majority of NPP changes were positively correlated with precipitation and negatively correlated with temperature, but the significance was not strong； only 23% of the area had a strong correlation between vegetation NPP changes and meteorological factors, and it was concentrated in the central Yanshan Mountains, while the rest of the area was mainly driven by reasons other than climatic factors. ③ Potentially improved （NPPH>0） and potentially degraded （NPPH<0） areas were roughly equally distributed, but human activities played a positive role in most of the areas （79%）； 76% of the areas were dominated by human activities in the actual improved areas and 58% in the actual degraded areas, and human activities were the main factor dominating the NPP succession of vegetation in the study area. The results of this study provide an important reference for the formulation of precise vegetation ecological protection and restoration policies in the Beijing-Tianjin-Hebei ecological barrier area.