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1

Comparative analysis of characterization methods of potential environmental pollution risk from livestock and poultry breeding

100%
Yan B., Yan J.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 4
Based on statistics data of livestock and poultry of Guangdong Province, seven characterization methods were used to characterize potential environmental pollution risk of livestock and poultry breeding (LPB) of Guangdong and were analyzed comparatively. The results showed that the results of different characterization methods of potential environmental pollution risk of LPB were generally uneven in spatial distribution. The maximum value of seven characterization methods of potential environmental pollution risk of LPB were all in Shunde District, but the minimum value of seven characterization methods of potential environmental pollution risk of LPB were in different counties. In addition, the number of counties exceeding the safety thresholds also had large differences among different characterization methods of potential environmental pollution risk of LPB. The maximum number, second number, and minimum number of counties exceeding safety thresholds was by the alarm value of pig manure equivalent load of farmland calculated by nitrogen (AVPMELFN), livestock density (LD), and the pig manure equivalent load of farmland calculated by phosphorus (PMELFP), which accounting for 82.22%, 53.89%, and 11.11% of total counties, respectively. It showed that the most stringent method was the AVPMELFN followed by the LD, and the least stringent method was the PMELFP.
2

Prediction of the distribution of Alpine tree species under climate change scenarios: Larix chinensis in Taibai Mountain (China)

81%
Zhao X., Meng H., Wang W., Yan B.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 2
Larix chinensis, an endangered and endemic alpine tree, occurs on Mt. Taibai in the Qinling Mountains, China. The extreme sensitivity of this species to climate change makes predicting its future distribution important. Using high-resolution remote-sensing imagery, and the Maxent model, we analysed the current distribution and forecast future distribution of L. chinensis under two climate change scenarios, IPCC A2 and IPCC B2. The results showed that three dominant climatic factors influenced the geographic distribution of L. chinensis: mean annual temperature, mean temperature of the coldest quarter, and precipitation of wettest month. Currently, L. chinensis mainly concentrated at 3100 m and covers an area of 53.52 km². The population on the southern slope covers approximately twice the area of that on the northern slope; the model simulations indicated that the area of suitable habitat would decrease continually under two climate change scenarios, A2 and B2; the decrease was more obvious in scenario A2, and the range in scenario A2 covers approximately twice the area of that in scenario B2. Under both scenarios, L. chinensis would first be extirpated at lower elevations, and the suitable habitat of this species would move to higher elevations in the Taibai Mountains.
3

Estimation of carrying capacity of livestock and poultry based on RS and GIS: a case in Minhou County, Fuzhou City

81%
Li Y., Yan B., Yan J., Shi W.
Polish Journal of Environmental Studies
|
2021
|
tom 30
|
nr 1
4

Variation characteristics and influencing factors on the number of livestock in the Hohhot area from 1986 to 2015

81%
Yan B., Yan J., Shi W., Li Y.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 3
5

Parameter optimization of double-excess runoff generation model

61%
Ren B., Liang J., Yan B., Lei X., Fu W., Ni. X., Guo J.
Polish Journal of Environmental Studies
|
2018
|
tom 27
|
nr 2
Research on the optimization of hydrological model parameters is an important issue in the field of hydrological forecasts, as these parameters not only directly impact the accuracy of forecast programs, but also relate to the development, application, and popularization of hydrological models. In this paper we selected the double-excess runoff generation model as the subject for research, and the data obtained from tens of flooding events in the Fen River Basin were used for the construction of these models. The SCE-UA and MOSCDE algorithms were then taken to optimize the models’ parameters. The results showed that: as compared with the SCE-UA algorithm, higher flood forecast accuracies were obtained through model parameter optimization using the MOSCDE algorithm. During the examination period, the compliance rate of the flood peak magnitude increased from 60% to 70%, while the compliance rate of the flood peak duration increased from 80% to 90%. The Nash-Sutcliffe efficiency (NSE) of the flood peak magnitudes increased from 0.664 to 0.878, which demonstrates an improvement in goodness-of-fit; the RMSE value of flood peak magnitudes also decreased from 399.8 to 236.84, thus showing a decrease in dispersion and an improvement in goodness-of-fit. With the continuous improvements made in hydrological parameter algorithms and the creation of new optimization algorithms, there is no doubt that the optimization of hydrological model parameters will become more reasonable.
6

Potential toxicity in crucian carp following exposure to metallic nanoparticles of copper, chromium, and their mixtures: A comparative study

61%
Liu Y., Yan Z., Xia J., Wang K., Ling X., Yan B.
Polish Journal of Environmental Studies
|
2017
|
tom 26
|
nr 5
Although study of the toxicity of metallic nanoparticles in aquatic organisms is increasing, there is still little known about their combined toxicity, especially in a comparative and integrated approach. The objective of this study is to compare the toxicity of copper nanoparticles (CuNP), chromium nanoparticles (CrNP), and their mixtures to crucian carp (Carassius auratus) through a comprehensive approach. A high median lethal concentration of CuNP (390.75 mg/L) and CrNP (551.03 mg/L) was calculated from the acute toxicity, indicative of low toxicity to crucian carp. After exposure for 10 d at sublethal concentrations, several biomarker responses, including the activities of brain acetylcholinesterase (AChE), gill sodium/ potassium-activated ATP (Na⁺/K⁺ -ATP), liver superoxide dismutase (SOD), and catalase (CAT) were significantly inhibited by all nanoparticles in most cases, implying the neurotoxicity, osmoregulatory toxicity, and oxidative damage of metallic nanoparticles. Thereafter, the integrated biomarker response version 2 (IBRv2) integrating all biomarker responses was applied to compare the toxicity, and therefore the toxicity order was tentatively proposed as: the mixtures ≈ CuNP＞CrNP, suggesting a synergistic effect in the mixtures. The findings will help to understand the ecological impacts of metallic nanoparticles in an aquatic environment in a more complete and accurate picture.
7

Tracking the fate of fertilizer nitrogen in a paddy rice field using isotope technology

61%
Yu X., Xu Y., Zhu H., Shutes B., Yan B., Chen X., Cheng R.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 1
8

Applying the dynamic critical precipitation method for flash flood early warning

61%
Kang A., Zhang K., Liang Z. J., Yan B., Lei X., Guo J.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 3
The flash flood early warning method based on dynamic critical precipitation is proposed, which takes into account the percentage saturation of soil moisture content in double-excess model. A series of historical precipitation data of various gauge stations in the upper catchment of the study area at the early warning cross-section are set as the input parameters, thereby the runoff generation and concentration in the catchment are obtained in the double-excess model, and the percent saturation of soil moisture content is calculated. Based on the warning discharge in combination with the percentage saturation of soil moisture content, the discriminant relations of the critical precipitation for the time intervals, including 0.5 h, 1 h, 1.5 h, 2 h, 2.5 h, and 3 h, are computed respectively using the inversion method. Using the precipitation data from ground rain gauge stations for year x and flood hydrograph data of x typical flood events for the Dayuhe River catchment, the SCE-UA algorithm is adopted to calibrate the parameters of the double-excess model, and the discriminant functions of dynamic critical precipitation for flash flood early warning with 6 time scales are validated using x representative historical flood hydrographs. The qualification ratio for flash flood early warning exceeds x, which demonstrates the feasibility and applicability of the proposed method.
9

Cloning of Hsp21 gene and its expression in Chinese shrimp Fenneropenaeus chinensis in response to WSSV challenge

61%
Gao H., Lai X., Kong J., Wang W., Meng X., Yan B., Cai S.
Journal of Applied Genetics
|
2014
|
tom 55
|
nr 2
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