Resistance Model Research Articles

Incorporating barriers restoration and stepping stones establishment to enhance the connectivity of watershed ecological security patterns

Enhancing the connectivity of watershed ecological security patterns (ESPs) is increasingly emphasized for preserving ecological processes. Yet the importance of small-scale conservation and restoration was ignored and few studies have quantitatively compared the contribution of barriers restoration and stepping stones establishment to landscape connectivity. In this study, taking Dongting Lake Basin as an example, a watershed ESP was constructed based on the minimum cumulative resistance model and optimized through graded barriers restoration and different stepping stones establishment. Then the enhancement effects of landscape connectivity were compared to identify the most cost-effective optimization scheme. The results showed that the average of six schemes only protected and repaired less than 1% of the total area, which could enhance corridor connectivity by about 12% and 16% for average corridor length and corridor cumulative resistance respectively. For the optimal ESP, establishing natural patches near the midpoint of longer corridors as stepping stones, increased the probability of connectivity by 21.05%, and reduced the average corridor length and corridor cumulative resistance of corridor connectivity by 17.99% and 15.48% respectively. It also increased network circuitry index of network connectivity from 0.541 to 0.570, compared with the original ESP, indicating the possibility of successful ecological flow increased effectively. It can be concluded that the connectivity enhancement of stepping stones approach was better than barriers restoration approach. This study highlights the importance of small-scale barriers restoration and stepping stones establishment in enhancing landscape connectivity.

Novel accurate steady-state thermal resistance model for power chips embedded in TTSVs heat dissipation array

a novel oblique pyramid equivalent heat dissipation model is proposed for theoretically analyzing heat dissipation capacity of power chips with embedded TTSVs. Extra carefully researching correction of oblique thermal resistance, additional lateral thermal resistance, and thermal resistance of TSV insulation sleeve, the accurate theoretical thermal resistance model was established. Setting the FEA simulating results based on COMSOL Multiphysics as benchmark, heat dissipation effects of variation of radius of TTSV (r), thickness of the power chip (H0), and side length of the single cell (L0) have been numerically investigated. The maximum temperature relative error of the proposed model with FEA simulated results is not more than 0.2 %, 1 %, and 0.5 % for variation of r, H0, and L0, respectively. The proposed model has been theoretically and numerically proven to be effective and accurate.

Study on the Shear Strength and Erosion Resistance of Sand Solidified by Enzyme-Induced Calcium Carbonate Precipitation (EICP).

Sand solidification of earth-rock dams is the key to flood discharge capacity and collapse prevention of earth-rock dams. It is urgent to find an economical, environmentally friendly, and durable sand solidification technology. However, the traditional grouting reinforcement method has some problems, such as high costs, complex operations, and environmental pollution. Enzyme-induced calcium carbonate precipitation (EICP) is an anti-seepage reinforcement technology emerging in recent years with the characteristics of economy, environmental protection, and durability. The erosion resistance and shear strength of earth-rock dams solidified by EICP need further verification. In this paper, EICP-solidified standard sand is taken as the research object, and EICP-cemented standard sand is carried out by a consolidated undrained triaxial test. A two-stage pouring method is adopted to pour samples, and the effects of dry density, cementation times, standing time, and confining pressure on the shear strength of cemented standard sand are emphatically analyzed. The relationship between cohesion, internal friction angle, and CaCO3 formation was analyzed. After the optimal curing conditions are obtained through the triaxial shear strength test, the erosion resistance model test is carried out. The effects of erosion angle, erosion flow rate, and erosion time on the erosion resistance of EICP-solidified sand were analyzed through an erosion model test. The results of triaxial tests show that the standard sand solidified by EICP exhibits strain softening, and the peak strength increases with the increase in initial dry density, cementation times, standing time, and confining pressure. When the content of CaCO3 increases from 2.84 g to 12.61 g, the cohesive force and internal friction angle change to 23.13 times and 1.18 times, and the determination coefficients reach 0.93 and 0.94, respectively. Erosion model test results indicate that the EICP-solidified sand dam has good erosion resistance. As the increase in erosion angle, erosion flow rate, and erosion time, the breach of solidified samples gradually becomes larger. Due to the deep solidification of sand by EICP, the development of breaches is relatively slow. Under different erosion conditions, the solidified samples did not collapse and the dam broke. The research results have important reference value and scientific significance for the practice of sand consolidation engineering in earth-rock dams.

Elemental evolution characteristics and influencing factors of green infrastructure network in karst mountain cities: a case study of Qianzhong urban agglomeration in Southwest China

BackgroundThe urban green infrastructure (GI) network is an important conduit for ecological flows and plays a crucial role in improving regional habitats, especially in karst areas that are highly ecologically fragile and sensitive. However, the existing research only focuses on the construction of GI network in karst mountain cities, and the evolution characteristics of its elements and driving mechanism are not clear, which is of great significance for guiding urban land use planning and comprehensively improving the quality of the ecological environment. In view of this, this study took Qianzhong urban agglomeration as the study area, based on multi-source data, and identified ecological sources through ecological resilience analysis. Considering the special geographic environment, the rock exposure rate factor was added to correct the resistance surface, and the minimum cumulative resistance (MCR) and gravity model were coupled to extract the GI network. The complex network topology characterization parameter was introduced to assess the spatial and temporal variations of ecological sources and corridors. Finally, the geographical detector was used to identify the dominant influencing factors and interactions of the spatial distribution of the GI network.ResultsThe results showed that from 2000 to 2020, the condition of GI network elements in the study area presented a decreasing and then an increasing trend. The ecological sources or corridors in highly urbanized areas were critical for ecological flow transport and the overall structural stability of the GI network. The influence of natural factors on the spatial distribution of the GI network gradually weakened, and the influence of human factors continuously increased. The spatial distribution of the GI network was influenced by multiple factors, and the interaction between all the factors was enhanced, which gradually changed from the interaction of natural factors to the interaction of human factors during the study period.ConclusionsThe research results will provide scientific references for the construction of an ecologically safe environment and sustainable development of karst mountain cities.

Noninvasive and fast method of calculation for instantaneous wave-free ratio based on haemodynamics and deep learning

Background and ObjectivesInstantaneous wave-free ratio (iFR) is a new invasive indicator of myocardial ischaemia, and its diagnostic performance is as good as the “gold standard” of myocardial ischaemia diagnosis: fractional flow reserve (FFR). iFR can be approximated by iFRCT, which is calculated based on noninvasive coronary CT angiography (CTA) images and computational fluid dynamics (CFD). However, the existing methods for calculating iFRCT fail to accurately simulate the resting state of the coronary artery, resulting in low computational accuracy. Furthermore, the use of CFD technology limits its computational efficiency, making it difficult to meet clinical application needs. The role of coronary microcirculatory resistance compensation suggests that microcirculatory resistance can be adaptively reduced to compensate for increases in coronary stenotic resistance, thereby maintaining stable myocardial perfusion in the resting state. It is therefore necessary to consider this compensation mechanism to establish a high-fidelity microcirculation resistance model in the resting state in line with human physiology, and so to achieve accurate calculation of iFRCT. MethodsIn this study we successfully collected clinical data, such as FFR, in 205 stenotic vessels from 186 patients with coronary heart disease. A neural network model was established to predict coronary artery stenosis resistance. Based on the compensation mechanism of coronary microcirculation resistance, an iterative solution algorithm for microcirculation resistance in the resting state was developed. Combining the two methods, a simplified single-branch model combining coronary stenosis and microcirculation resistance was established, and the noninvasive and rapid numerical calculation of iFRCT was performed. ResultsThe results showed that the mean squared error (MSE) between the pressure drop predicted by the neural network value for the coronary artery stenosis model and the ground truth in the test set was 0.053 %, and correlation analysis proved that there was a good correlation between them (r = 0.99, p < 0.001). With reference to clinical diagnosis of myocardial ischaemia (using FFR as the gold standard), the diagnostic accuracy of the iFRCT calculation model for the 205 cases was 88.29 % (r = 0.71, p < 0.001), and the total calculation time was < 8 s. ConclusionsThe results of this study demonstrate the utility of a simplified single-branch model in an iFRCT calculation method based on haemodynamics and deep learning, which is important for noninvasive and rapid diagnosis of myocardial ischaemia.

Landscape and conservation genetics of western black crested gibbons (Nomascus concolor) in China.

Despite decades of field study, very little is known about the molecular ecology of gibbons, particularly as it relates to their ability to disperse across degraded and fragmentary landscapes. The critically endangered western black crested gibbon (Nomascus concolor) has been reduced to a small, fragmented population with about 1300 individuals. In the largest population genetic study of free-ranging gibbons to date, we sampled 47 of these gibbons from 13 sites in China and generated 15 polymorphic autosomal microsatellite markers. We identify three population clusters of N. concolor in Yunnan centered in 1) the Wuliang and Ailao Mountains, 2) the Yongde Daxueshan Mountains, and 3) an isolated remnant near the border with Vietnam. Within the Wuliang Mountains, we identified four subclusters, three of which are bounded by high-altitude rhododendron forest, and one that is isolated from the main population by ~2 km of degraded forest and pasture. Least-cost path analysis and isolation by resistance modeling demonstrates that the population genetic distances among gibbons in Wuliangshan National Nature Reserve are significantly correlated with geographic paths that avoid use of high-altitude rhododendron forest in favor of evergreen broadleaf forest. Although these gibbons have likely undergone reductions in heterozygosity from recent consanguineous mating, we suggest that their active avoidance of inbreeding on the population level maintains higher than expected levels of genetic diversity. This research provides new insights into how gibbons interact with heterogeneous environments and expands our understanding of their molecular ecology and conservation genetics.

PACAP ameliorates obesity-induced insulin resistance through FAIM/Rictor/AKT axis.

Obesity and obesity-related insulin resistance have been a research hotspot. Pituitary adenylate cyclase activating polypeptide (PACAP) has emerged as playing a significant role in energy metabolism, holding promising potential for attenuating insulin resistance. However, the precise mechanism is not fully understood. Palmitic acid and a high-fat diet (HFD) were used to establish insulin resistance model in Alpha mouse liver 12 cell line and C57BL/6 mice, respectively. Subsequently, we assessed the effects of PACAP both in vivo and in vitro. Lentivirus vectors were used to explore the signaling pathway through which PACAP may ameliorate insulin resistance. PACAP was found to selectively bind to the PACAP type I receptor receptor and ameliorate insulin resistance, which was characterized by increased glycogen synthesis and the suppression of gluconeogenesis in the insulin-resistant cell model and HFD-fed mice. These effects were linked to the activation of the Fas apoptotic inhibitory molecule/rapamycin-insensitive companion of mammalian target of rapamycin/RAC-alpha serine/threonine-protein kinase (FAIM/Rictor/AKT) axis. Furthermore, PACAP ameliorated insulin resistance by increasing solute carrier family 2, facilitated glucose transporter members 2/4 and inhibiting gluconeogenesis-related proteins glucose 6-phosphatase catalytic subunit 1 and phosphoenolpyruvate carboxykinase 2 expression. Meanwhile, the phosphorylation of hepatic AKT/glycogen synthase kinase 3β was promoted both in vivo and in vitro by PACAP. Additionally, PACAP treatment decreased body weight, food intake and blood glucose levels in obese mice. Our study shows that PACAP ameliorated insulin resistance through the FAIM/Rictor/AKT axis, presenting it as a promising drug candidate for the treatment of obesity-related insulin resistance.

Trajectory design based on frictional resistance of deflector in a hydraulic radial drilling system

The trajectory design is a key factor affecting the frictional resistance of the deflector, which is crucial for the drilling ability of the hydraulic radial drilling system. In this research, the trajectory design model and geometric constraints model of a deflector are established by analyzing the geometric relationship of the deflector and considering the geometric constraints of the casing. According to the actual contact form between the high-pressure hose and the deflector, the theoretical model of frictional resistance is built based on segmental rigidization and micro-element methods. The theoretical model is verified by the deflector friction experiment. The results demonstrate a good agreement between the experimental results of friction resistance of different sizes of high-pressure hoses and the theoretical results, with an error of less than 7%. The influence of critical parameters of deflector trajectory on the friction resistance is studied by coupling the geometric constraints model and the frictional resistance theoretical model of the deflector. The findings show that the deflector’s frictional resistance increases with the inclination angle β of the inclined-straight section and decreases with the increase in the radius R of the bending segment, the inclination angle ω of the straightening segment, and the channel radius of r deflector. A new trajectory parameters of the deflector are presented by taking a five-inch casing as an example, they are β = 9°, R = 92 mm, ω = 108°, r = 17 mm. The research results provide a theoretical rationale for designing a low-frictional resistance deflector.

Evaluating the surface water pollution risk of mineral resource exploitation via an improved approach: a case study in Liaoning Province, Northeastern China.

Pollution from mineral exploitation is an important risk factor affecting surface water environment in mineral regions. It is urgent to construct a simple and accurate model to assess the surface water pollution risk from mineral exploitation in the regional scale. Thus, taking a mining province namely Liaoning in northeastern China as the study area, we proposed a framework to simulate the transport process of pollutants from mineral exploitation points to the surrounding surface water based on the "source-sink" theory. In our framework, we adopted the regional growth method (RGM) to extract the potential polluted water area as the certain "sink"considering the influence of the topography, and then applied Minimum Cumulative Resistance (MCR) model to assess the surface water pollution risk from mineral exploitation. The results revealed that: (1) 9.5% of the water areas were located at the potential impact area of MEPs. (2) The total value of resistance surface in Liaoningis relatively low, and gradually decreased from west to east. (3) MEPs in Liaoning had a high risk and seriously threatened the surface water environment, among 2125 MEPs, 733 MEPs (32.99%) were assessed as extremely high risk level, and about 35% of the MEPs were distributed within 10KM buffer zone of surface water. (4) Water pollution risk of MEPs in Dalian, Tieling, Fuxin and Dandong need to be emphasized. (5) Compared to previous studies, we considered the topographical influence before applying MCR model directly, so the results of water pollution risk were more reliable. This study provides a methodological support and scientific reference for the water environment protection and regional sustainable development.

Excess Branched-Chain Amino Acids Suppress Mitochondrial Function and Biogenic Signaling but Not Mitochondrial Dynamics in a Myotube Model of Skeletal Muscle Insulin Resistance.

Branched-chain amino acids (BCAA) are correlated with severity of insulin resistance, which may partially result from mitochondrial dysfunction. Mitochondrial dysfunction is also common during insulin resistance and is regulated in part by altered mitochondrial fusion and fission (mitochondrial dynamics). To assess the effect of BCAA on mitochondrial dynamics during insulin resistance, the present study examined the effect of BCAA on mitochondrial function and indicators of mitochondrial dynamics in a myotube model of insulin resistance. C2C12 myotubes were treated with stock DMEM or DMEM with additional BCAA at 0.2 mM, 2 mM, or 20 mM to achieve a continuum of concentrations ranging from physiologically attainable to supraphysiological (BCAA overload) both with and without hyperinsulinemia-mediated insulin resistance. qRT-PCR and Western blot were used to measure gene and protein expression of targets associated with mitochondrial dynamics. Mitochondrial function was assessed by oxygen consumption, and mitochondrial content was measured using mitochondrial-specific staining. Insulin resistance reduced mitochondrial function, peroxisome proliferator-activated receptor gamma coactivator 1-alpha mRNA, and citrate synthase expression mRNA, but not protein expression. Excess BCAA at 20 mM also independently reduced mitochondrial function in insulin-sensitive cells. BCAA did not alter indicators of mitochondrial dynamics at the mRNA or protein level, while insulin resistance reduced mitochondrial fission protein 1 mRNA, but not protein expression. Collectively, BCAA at excessively high levels or coupled with insulin resistances reduce mitochondrial function and content but do not appear to alter mitochondrial dynamics under the tested conditions.

Understanding Voter Resistance to Political Campaigns: Evidence from National Elections of Pakistan

Political marketing literature acknowledges the pivotal role of marketing campaigns in building political support, yet a notable gap exists in understanding voters’ resistance to political campaigns. This paper argues that voters’ resistance can be managed if their attitudes are understood. Grounded in the Tripartite theory of attitude that conceptualizes attitude as a complex relationship between cognition (voter’s apathy, skepticism and cynicism), affection (voter’s dissatisfaction and frustration) and conation (voter’s resistance to political campaigns), the study tests a model for understanding resistance to political marketing. An empirical investigation of 454 participants from 2018 national elections in Pakistan, utilizing a structured questionnaire for data collection and employing structural equation modeling analysis techniques, reveals that skepticism and dissatisfaction significantly fuel voters’ resistance to political efforts. These factors engender disbelief, erode trust, and diminish interest in political candidates and their parties. Based on these findings, we draw implications for advocating citizen engagement over a sole reliance on advertisements to mitigate negative voter attitudes toward political campaigns.

Looking for a way out: The dynamics of slum life, poverty, and everyday resistance in Katherine Boo’s Behind the Beautiful Forevers

This article looks into the implications of urban informality in Katherine Boo’s Behind the Beautiful Forevers: Life, Death and Hope in a Mumbai Slum (2012) as represented in slum life and urban poverty. It aims to investigate the impact of urban poverty on the everyday practices of slum dwellers and their endeavors to escape the trap of poverty in an attempt to highlight the human dimension of the slum. The article seeks to unravel multi-layers of the interaction between people and poverty and the differing models of resistance to poverty and social exclusion depicted in the nonfiction narrative. The article examines slum life from a descriptive sociological perspective with a detailed description of how people survive in poverty. The study of the culture of slums entails an analysis of the survival techniques and everyday practices of slum dwellers, the relations and patterns of behavior among the different categories of people inhabiting a slum, and the outcomes of the interplay between place, culture, and power relations in such communities. This is implemented through an eclectic sociological approach that comprises theories of space, culture, and resistance as proposed by James Scott, Theodore W. Schultz, and Henri Lefebvre.

Quantitative Prediction of Human Immunodeficiency Virus Drug Resistance.

Drug resistance of pathogens, including viruses, is one of the reasons for decreased efficacy of therapy. Considering the impact of HIV type 1 (HIV-1) on the development of progressive immune dysfunction and the rapid development of drug resistance, the analysis of HIV-1 resistance is of high significance. Currently, a substantial amount of data has been accumulated on HIV-1 drug resistance that can be used to build both qualitative and quantitative models of HIV-1 drug resistance. Quantitative models of drug resistance can enrich the information about the efficacy of a particular drug in the scheme of antiretroviral therapy. In our study, we investigated the possibility of developing models for quantitative prediction of HIV-1 resistance to eight protease inhibitors based on the analysis of amino acid sequences of HIV-1 protease for 900 virus variants. We developed random forest regression (RFR), support vector regression (SVR), and self-consistent regression (SCR) models using binary vectors containing values from 0 or 1, depending on the presence of a specific peptide fragment in each amino acid sequence as independent variables, while fold ratio, reflecting the level of resistance, was the predicted variable. The SVR and SCR models showed the highest predictive performances. The models built demonstrate reasonable performances for eight out of nine (R2 varied from 0.828 to 0.909) protease inhibitors, while R2 for predicting tipranavir fold ratio was lower (R2 was 0.642). We believe that the developed approach can be applied to evaluate drug resistance of molecular targets of other viruses where appropriate experimental data are available.

Multi-scale simulation and optimization on a thermal management system of intermediate circuit and experiment validation

In the system-level simulations of heat transfer systems, the characteristics of heat exchangers are often considered constant or used in empirical formulas, which affect the accuracy of the system model. Herein a multi-scale simulation method to analyze the heat transfer characteristics of a thermal management system, including an intermediate loop is proposed. The system model is developed based on the heat current method and flow resistance models. By applying COMSOL LiveLink for MATLAB module, a multi-scale model is obtained, which combines three-dimensional numerical models of the heat exchangers with the system model. Compared to the experimental results, the relative errors associated with the outlet temperatures and heat transfer rate are less than 1.1% and 8.2 %, respectively, thus validating the model. Discussions on the effects of the geometric structure of the heat exchangers on the system show that a plate heat exchanger with 12 plates and a plate spacing of 8 mm is better. For achieving systematic maximum heat dissipation for a certain pumping power consumption, a multi-scale optimization method is proposed by coupling the Lagrange function and numerical model. The results show that the total heat transfer rate improves by 5.89 %, from 8314.81 W to 8804.35 W.

Theoretical and experimental analysis of evaporative cooling with hydrophilic screen mesh on condenser surface

In this study, we theoretically and experimentally analyzed the effect of evaporative cooling on the external thermal resistance of a condenser with a water-filled hydrophilic screen mesh. To calculate the external thermal resistance of the condenser theoretically, the external thermal resistance model was developed, considering evaporative cooling in the screen mesh. The evaporative mass flow rate in the screen mesh was calculated using the Lewis number, which can convert heat transfer to mass transfer. Especially, the maximum flow rate absorbed by the screen mesh was theoretically determined by the capillary limit. In experimental approach, hydrophilic screen meshes with mesh numbers M100, M150, and M200 were manufactured and attached to an aluminum plate simulating the condenser surface. The external thermal resistance of the condenser was measured. Based on the results, the theoretical model was well matched with experimental results. The effects of the air velocity, mesh number, and heat flux on the external thermal resistance of the condenser with evaporative cooling in the water-filled hydrophilic screen mesh were investigated. Finally, it is shown that the external thermal resistance of the condenser with evaporative cooling using the water-filled hydrophilic screen mesh can be reduced up to an average of 92 %.

Motion resistance modelling and validation in winter conditions with varying air drag

Range prediction is vital for battery electric vehicles, and the main source of errors in range prediction is often the uncertainty in motion resistance. Rig and wind tunnel measurements can be used to find the motion resistance of a specific vehicle combination under specified weather conditions. However, real-life variation of the operating conditions of heavy-duty vehicles makes testing impractical. This paper proposes and validates a model of motion resistance with parameters adapted to actual road weather conditions. The model is validated in winter conditions with varying wind, using a vehicle equipped with a wind sensor. The results show that the proposed model captures the motion resistance with high accuracy. Results also indicate that it is crucial to take weather effects into account when modelling motion resistance, particularly in winter conditions.

Tourism in Historic Urban Areas: Construction of Cultural Heritage Corridor Based on Minimum Cumulative Resistance and Gravity Model—A Case Study of Tianjin, China

Tourism in Historic Urban Areas: Construction of Cultural Heritage Corridor Based on Minimum Cumulative Resistance and Gravity Model—A Case Study of Tianjin, China

Integrating high-throughput phenotyping and genome-wide association studies for enhanced drought resistance and yield prediction in wheat.

Drought, especially terminal drought, severely limits wheat growth and yield. Understanding the complex mechanisms behind the drought response in wheat is essential for developing drought-resistant varieties. This study aimed to dissect the genetic architecture and high-yielding wheat ideotypes under terminal drought. An automated high-throughput phenotyping platform was used to examine 28 392 image-based digital traits (i-traits) under different drought conditions during the flowering stage of a natural wheat population. Of the i-traits examined, 17 073 were identified as drought-related. A genome-wide association study (GWAS) identified 5320 drought-related significant single-nucleotide polymorphisms (SNPs) and 27 SNP clusters. A notable hotspot region controlling wheat drought tolerance was discovered, in which TaPP2C6 was shown to be an important negative regulator of the drought response. The tapp2c6 knockout lines exhibited enhanced drought resistance without a yield penalty. A haplotype analysis revealed a favored allele of TaPP2C6 that was significantly correlated with drought resistance, affirming its potential value in wheat breeding programs. We developed an advanced prediction model for wheat yield and drought resistance using 24 i-traits analyzed by machine learning. In summary, this study provides comprehensive insights into the high-yielding ideotype and an approach for the rapid breeding of drought-resistant wheat.

Evaluation of landscape ecological security pattern via the “pattern-function-stability” framework in the Guanzhong Plain Urban Agglomeration of China

Most studies have assessed and constructed landscape ecological security patterns (LESPs) primarily from the perspective of landscape morphology by employing morphological spatial pattern analysis, with little attention paid to fundamental ecosystem attributes (such as ecosystem functions and stability). Thus, this study proposed a comprehensive evaluation and optimization framework for LESPs from the perspective of “mode function stability” by integrating assessment landscape pattern, ecological function, and landscape stability. A comprehensive evaluation and optimization of the LESPs was conducted using the Minimum Cumulative Resistance (MCR) model in the Guanzhong Plain Urban Agglomeration (GPUA) as the research area. The results showed that: (1) Generally, the landscape quality in urban agglomerations was relatively low because of the large area of agricultural vegetation, high human interference, and landscape fragmentation, which caused low levels of landscape pattern, function, and stability. (2) LESPs were mainly determined by landscape stability in urban agglomerations due to low-quality ecosystems, rapid landscape transformation, and severe anthropogenic disturbances. (3) There was a large variation in the landscape function and stability of a certain landscape type due to their different structures and human interference across space in urban agglomerations. According to assessment by “pattern-function-stability” framework, the ecological sources and corridors covered with natural forest were the crucial cornerstone to constructing LESPs, and the rivers in crop planting areas were the inevitably selected corridors, but their ecological function and stability needed further improvement in construction. (4) The framework can assess spatial patterns and ecological functions to further the stability and sustainability of the landscape in maintaining ecological security and facilitating the identification of improvement objectives or measures of individual ecological sources or corridors in regional ecological infrastructure construction practices.

The Evolution of Forest Landscape Connectivity and Ecological Network Construction: A Case Study of Zhejiang’s Ecological Corridors

As main components of terrestrial ecosystems, forests play irreplaceable roles in maintaining ecological balance and protecting the basic environment for human survival and development. In this study, the dynamic changes in the forest landscape connectivity in Zhejiang province in 2000, 2010, and 2020 were detected by identifying ecological sources and evaluating connectivity indexes based on morphological spatial analysis (MSPA) and a minimum cumulative resistance (MCR) model. The results are as follows: (1) The forest area of Zhejiang increased by 64.88% from 2000 to 2020, indicating that the overall habitat quality has improved and that ecological risks have decreased, which are attributed to Zhejiang’s adherence to comprehensive environmental management. (2) Regions with low connectivity are distributed mainly in the north, where human activities are intensive. The overall pattern of high connectivity in the middle of the region and low connectivity elsewhere demonstrates the uneven distribution of forest landscape connectivity across the province. (3) The extracted ecological corridors have a mesh-like structure that is dense in the middle and slack in the north. Important corridors have disappeared over time, indicating potential issues in maintaining connectivity for species migration. (4) These results can provide optimization strategies for ecological infrastructure planning in Zhejiang province and offer a theoretical reference for the optimization of the ecological network system.