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【Objective】The present paper aimed to explore the changes of eco-environmental quality brought by land use transformation and analyze the influencing factors of spatial differentiation of eco-environmental quality. It can provide scientific support for land management and regional planning in the social and ecological sustainable development of Sichuan province.【Method】Based on the remote sensing monitoring data of land use in Sichuan province in 2000, 2010 and 2020, starting from the dimension of land use function, the paper analyzed and studied the eco-environmental effects and influencing factors of land use transformation in Sichuan province from 2000 to 2020 by using land use transfer matrix, land use center of gravity migration, eco-environmental index, contribution rate of ecological quality and geographic detector.【Result】（i）The transformation of land function structure in Sichuan province from 2000 to 2020 was characterized by the transfer of agricultural production land to forest land and forage ecological land; Spatially, the transformation featured that the center of gravity of production and living land was constantly away from the geometric center, while the center of gravity of ecological land was continuously close to the geometric center.（ii）The eco-environmental quality index of Sichuan province in 2000, 2010 and 2020 was 0.4968, 0.4969 and 0.5009 respectively. The regional eco-environmental quality generally showed the distribution characteristics of ‘high in the West and low in the East’.（iii）From 2000 to 2010, the transfer of agricultural production land to forest and pasture ecological land was the main land transformation to promote the improvement of ecological environment; The transfer of forest land ecological land to pasture and other ecological land from 2000 to 2010 was the main land transformation leading to the deterioration of ecological environment. From 2010 to 2020, the production land of forest land would be transferred to agricultural production land, forage and other ecological land.（iv）The spatial differentiation of regional eco-environmental quality was affected by many factors such as nature, society and economy, among which elevation, topographic relief and population density were the main influencing factors.【Conclusion】The characteristics of land use transformation in Sichuan province are as follows: The center of gravity of production and living land is constantly deviated from the geometric center of gravity, and the imbalance of production and living space distribution is enhanced. The center of gravity of ecological land keeps approaching the geometric center of gravity, and the spatial distribution of ecological land tends to be balanced; The changing characteristics of ecological environment quality are as follows: The ecological environment quality index is constantly increasing, the area of high-quality and high-quality ecological environment areas is rising, and the overall regional ecological environment quality structure is constantly optimized; Explore the impact mechanism of spatial differentiation of eco-environmental effects, and draw the conclusion that regional eco-environmental quality differentiation is mainly affected by elevation, terrain undulation and population density. [ABSTRACT FROM AUTHOR]

[Objective] The present paper explored the spatial distribution pattern and driving factors of aquaculture in Sichuan province, which aimed to provide reference for optimizing the layout of aquaculture and then promoting the quality and product of this industry. [Method] Taking the country (municipal district) of Sichuan province as the basic spatial research unit, with the help of the province' s fishery statistical yearbook and local one, the spatial distribution pattern, influencing facotrs and spatial heterogeneity of domaint factors of aquaculture in Sichuan province were analyzed by using the spatial autocorrelation analysis method (Moran' s I), the geo-detercor and the geographically weighted regression (GWR) model respectively. [Result] The results showed that both aquaculture area and product were characterised by a significantby positive spatial correlation and the plain and hilly areas along the Minjiang and Tuojiang Rivers in eastern Sichuan (including Rong county, Weiyuan county, Zizhong county, Jingyan county, Renshou county, Yanjiang district, Jianyang city, etc.) were the province' s primary aquaculture cluster; the aquaculture area, average yield level, the number of freshwater fish fry and aquaculture labor force were main influencing factors of aquaculture product in Sichuan province ; In the positive regression coefficient effect of domain factors, aquaculture area decreased from the middle to the nonh and south sides, the average yield level decreased from the nonheast to the southwest and the number of freshwater fish fry decreased from the nonh to the south. And the aquaculture labor force transited from negative value to positive value from the southeast to the west, and gradually increased. [Conclusion] The research on the spatial pattern and influencing factors of aquaculture in Sichuan province would provide a scientific basis for the intensive and differentiated development of aquaculture in this province, and would be one of the effective means to optimize the layout of aquaculture in Sichuan province and then promote the sustainable development of the industry. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to evaluate the epidemic status of common pathogens large-scale pig farms in Sichuan.【Method】In this study, 283 samples(pathological tissues, boar semen, miscarriage and stillbirth) were collected and detected by bacterial isolation and identification, RT-PCR, PCR. 【Result】The positive rates of CSFV, PRRSV, PRRSV NADC30-Like, PCV2, PRV, APP, PM and SS2 in the pathological tissues samples of 106 pigs were 7.55 %(8/106),40.57 %(43/106), 20.75 %(22/106),34.91 %(37/106),16.04 %(17/106),9.43 %(10/106),19.81 %(21/106) and 4.72 %(5/106), respectively. Among the percentage of multiply infections was 60.49 %(49/81). The pathogens infection of PRRSV or PCV2 not only emerges in throughout the year but also occurs frequently with other pathogens infection and bacterial infection are most common in summer. The positive rates of CSFV, PRRSV, PCV2 and PRV in 68 boar semen samples were 10.29 %(7/68), 30.88 %(21/68), 20.59 %(14/68) and 20.59 %(14/68), respectively. Among the 38 positive samples, the percentage of single infections was 52.63 %(20/38). The positive rates of CSFV, PRRSV, PCV2 and PRV in 63 miscarriage and stillbirth samples were 6.35 %(4/63),46.03 %(29/63),38.10 %(24/63) and 30.16 %(19/63), respectively. The most common infection type was PRRSV with other pathogens infection and PRRSV was more common in throughout the year and the percentage of multiply infections was 74.50 %(38/51). The infections of PEDV and PoRV are common in spring, autumn and winter. The positive rate of PEDV and PORV were 56.52 %(26/46) and 26.09 %(12/46) in intestinal mucosa and feces of 46 diarrhea pig samples.【Conclusion】The Prevention and control of PRRSV, PCV2, PRV and PEDV were still key point in the future, meanwhile, the multiple pathogen infection and new variants PRRSV NADC30-Like is also difficult to prevent from large-scale pig farms in Sichuan area. [ABSTRACT FROM AUTHOR]