Impacts of nature reserve policy on regional ecological environment quality: A case study of Sanjiangyuan region.

Uncovering the ecological effectiveness of nature reserve policies will help protect and manage nature reserves in the future. Taking Sanjiangyuan region as an example, we examined the impacts of the spatial layout characteristics of natural reserves on the ecological environment quality by constructing the dynamic degree of land use and land cover change index, and depicted the spatial differences of the ecological effectiveness of natural reserve policies both inside and outside the natural reserves. Combined with ordinary least squares and field survey results, we explored the influencing mechanism of nature reserve policies on ecological environment quality. The results showed that the ecological quality of the whole region of Sanjiangyuan had been improved significantly since the implementation of the nature reserve policies, and that the transformation of unused land into ecological land was the most important type of land use change for the ecological environment quality improvement. The ecological effectiveness of large-scale nature reserves with concentrated and contiguous distribution was obvious, while the ecological effectiveness of small-scale nature reserves with scattered distribution and close to the administrative boundaries was relatively small. Although the ecological effectiveness of nature reserves was better than that of non-reserved areas, the ecological improvement of nature reserves and the surrounding areas was synchronous. The nature reserve policy had significantly improved ecological environment quality by implementing ecological protection and restoration projects in nature reserves. Meanwhile, it had alleviated the pressure of farmers and herdsmen's activities on the ecological environment by taking measures such as grazing restriction and guiding conversion of industry and production. In the future, we should promote the construction of ecosystem integrity protection network system with National Park as the core, strengthen the integrated protection and linkage management of National Park and surrounding areas, and help farmers and herdsmen further broaden their livelihoods.

Correlation and Prognostic Assessment of Low T3 Syndrome and Norepinephrine Dosage for Patients with Sepsis: A Retrospective Single-Center (Cohort) Study.

Purpose: To investigate the correlation and prognostic significance of low triiodothyronine (T3) syndrome and norepinephrine dosage in patients with sepsis and septic shock. Methods: This single-center, retrospective, cohort study enrolled 169 patients with sepsis and septic shock that were admitted to the intensive care unit of First Hospital of Nanchang, Nanchang, China from June 2017 to July 2019. All included patients were followed up for 28 days or died, whichever was earlier. Patients with free T3 (FT3) of <3.1 pmol/L were considered with low T3 syndrome. The correlation and prognostic significance of the FT3 and maximum dosage of norepinephrine (MDN) within 72 h, as well as other clinical indicators, were analyzed by using correlation analysis, principal component analysis, receiver operating characteristic curve, Youden index, and logistic regression. Results: A total of 138 patients were allocated to the low T3 group. FT3 inversely correlated with the Sequential Organ Failure Assessment (SOFA) score within 24 h, fluid resuscitation volume within 24 h, and lactic acid levels, and positively correlated with the mean arterial pressure. The critical values of age, SOFA, and MDN for predicting the 28-day mortality were 79.5 years, 8.5 points, and 0.61 µg/kg/min, respectively. The mortality of the low T3 and normal T3 groups was similar. Considering the MDN of 0.61 µg/kg/min as the cutoff value, the mortality between the two groups was significantly different. Conclusion: Among patients with sepsis and septic shock, FT3 was inversely correlated with the disease severity. An MDN ≥ 0.61 µg/kg/min within 72 h may be an important prognostic indicator.

[Biogeochemical processes of the major ions and dissolved inorganic carbon in the Guijiang River].

Within the drainage basin, information about natural processes and human activities can be recorded in the chemical composition of riverine water. The analysis of the Guijiang River, the first level tributary of the Xijiang River, demonstrated that the chemical composition of water in the Guijiang River was mainly influenced by the chemical weathering of carbonate rocks within the drainage basin, in which CO2 was the main erosion medium, and that the weathering of carbonate rock by H2SO4 had a remarkable impact on the water chemical composition in the Guijiang River. Precipitation, human activities, the weathering of carbonate rocks and silicate rocks accounted for 2.7%, 6.3%, 72.8% and 18.2% of the total dissolved load, respectively. The stable isotopic compositions of dissolved inorganic carbon (delta13C(DIC)) indicated that DIC in the Guijiang River had been assimilated by the phytoplankton in photosynthesis. The primary production of phytoplankton contributed to 22.3%-30.9% of particulate organic carbon (POC) in the Guijiang River, which implies that phytoplankton can transform DIC into POC by photosynthesis, and parts of POC will sink into the bottom of the river in transit, which leads into the formation of burial organic carbon.

[Characteristic of ammonia nitrogen adsorption on karst underground river sediments].

Karst aquifers are one of the most important aquifers in Southwestern China. One of the characteristics of karst aquifers is the enhanced permeability permits high flow velocities are capable of transporting suspended and bedload sediments. Mobile sediment in karst may act as a vector for the transport of contaminates. 14 sediment samples were collected from two underground rivers in two typical karst areas in Liuzhou city, Guangxi Autonomous Region, China. According to simulated experiment methods, characteristic of adsorption of ammonia nitrogen on sediment was studied. The results of ammonia nitrogen adsorption dynamics on sediments showed that the maximum adsorption velocity was less than 2 h. The adsorption balance quantity in 5 h accounted for 71% - 98% of the maximum adsorption quantity. The maximum adsorption quantity of ammonia nitrogen was 385.5 mg/kg, which was sediment from a cave in the middle areas of Guancun underground river system. The study of isotherm adsorption indicated adsorption quantity of NH4+ increase followed by incremental balance concentration of NH4+ in the aquatic phase. Adsorption quantity of ammonia nitrogen in sediments has a relative linear relationship with adsorption balance concentrations. Adsorption-desorption balance concentrations were all low, indicating sediments from underground rivers have great adsorption potential. Under the condition of low and high concentrations of ammonia nitrogen in overlying water, Langmuir and Tempkin couldn't simulate or simulate results couldn't reach remarkable level, whilst Linear and Freundlich models could simulate well. Research on different type sediments, sampling times and depths from two underground rivers shows characteristic of ammonia nitrogen adsorption on karst underground river sediments doesn't have good correspondence with the type of sediments. One of the reasons is there is no big difference between sediments in the development of climate, geology, hydrological conditions and pollution history. The other reason maybe the article is lack of research on pH, salinity and others factors which may affect adsorption and desorption.

[Vulnerability of eco-economy in northern slope region of Tianshan Mountains].

Based on the theoretical meaning of vulnerability, a vulnerability assessment of eco-econom in fifteen counties in the northern slope region of Tianshan Mountains was conducted. The ecosystem services change to land use was regarded as the impact, and based on the fourteen indices from resource holding, society development, and economy development statistic data, the adaptive ability was evaluated by using the methods of analytic hierarchy process (AHP) and fuzzy synthetic evaluation. On the basis of assessment results of impact and adaptive capacity, the fifteen counties were divided into five classes under the assessment principles, and the district with higher-class number was of more vulnerability. The first class included Usu City and Changji City, the second class included Hutubi County, Miquan County, Fukang City, Jimsar County, Qitai County and Mori Kazak Autonomous County, the third class included Karamay City and Urumqi City, the fourth class included Kuitun City and Shawan County, and the fifth class included Jinghe County, Shihezi City and Manas County. The vulnerability reflected the level of eco-environment change and socioeconomic development, and the vulnerability assessment could be a good way to ensure the sustainable development. Aiming to decrease the vulnerability, various districts belonging to different class of vulnerability should establish relevant tactics according to the vulnerability factors to accelerate the region's sustainable development.