Bijie City Research Articles

Analysis of the Influence of Forests on Landslides in the Bijie Area of Guizhou

Forests are an important part of the ecological environment, and changes in forests not only affect the ecological environment of the region but are also an important factor causing landslide disasters. In order to correctly evaluate the impact of forest cover on landslide susceptibility, in this paper, we build an evaluation model for the contribution of forests to the landslide susceptibility of different grades based on survey data for forest land change in Bijie City and landslide susceptibility data, and discuss the effects of forest land type, origin, age group, and dominant tree species on landslide susceptibility. We find that forests play a certain role in regulating landslide susceptibility: compared with woodland, the landslide protection ability of shrubland is stronger. Furthermore, natural forests have a greater inhibitory effect on landslides than artificial forests, and compared with young forest, mature forest and over-mature forest, middle-aged forest and near-mature forest have stronger landslide protection abilities. In addition, the dominant tree species in different regions have different impacts on landslides. Coniferous forests such as Chinese fir and Cryptomeria fortunei in Qixingguan and Dafang County have a low ability to prevent landslides. Moreover, the soft broad tree species found in Qianxi County, Zhijin County, Nayong County and Jinsha County are likely to cause landslides and deserve further research attention. Additionally, a greater focus should be placed on the landslide protection of walnut economic forests in Hezhang County and Weining County. Simultaneously, greater attention should be paid to the Cyclobalanopsis glauca tree species in Weining County because the area where this tree species is located is prone to landslides. Aiming at addressing the landslide susceptibility existing in different forests, we propose forest management strategies for the ecological prevention and control of landslides in Bijie City, which can be used as a reference for landslide susceptibility prevention and control.

The Changes of Spatiotemporal Pattern of Rocky Desertification and Its Dominant Driving Factors in Typical Karst Mountainous Areas under the Background of Global Change

There are significant differences in the dominant driving factors of rocky desertification evolution in different historical periods in southwest karst mountainous areas. However, previous studies were mostly conducted in specific periods. In this study, taking Bijie City as an example, the spatial and temporal evolution pattern of rocky desertification in Bijie City in the recent 35 years was analyzed by introducing the feature space model and the gravity center model, and then the dominant driving factors of rocky desertification in the study area in different historical periods were clarified based on GeoDetector. The results were as follows: (1) The point-to-point B (bare land index)-DI (dryness index) feature space model has high applicability for rocky desertification monitoring, and its inversion accuracy was 91.3%. (2) During the past 35 years, the rocky desertification in Bijie belonged to the moderate rocky desertification on the whole, and zones of intensive and severe rocky desertification were mainly distributed in the Weining Yi, Hui, and Miao Autonomous Region. (3) During 1985–2020, the rocky desertification in Bijie City showed an overall weakening trend (‘weakening–aggravating–weakening’). (4) From 1985 to 2020, the gravity center of rocky desertification in Bijie City moved westward, indicating that the aggravating degree of rocky desertification in the western region of the study area was higher than that in the eastern region. (5) The dominant factors affecting the evolution of rocky desertification in the past 35 years shifted from natural factor (vegetation coverage) to human activity factor (population density). The research results could provide decision supports for the prevention and control of rocky desertification in Bijie City and even the southwest karst mountainous area.

Landslide Susceptibility Assessment Considering Spatial Agglomeration and Dispersion Characteristics: A Case Study of Bijie City in Guizhou Province, China

Landslide susceptibility assessment serves as a critical scientific reference for geohazard control, land use, and sustainable development planning. The existing research has not fully considered the potential impact of the spatial agglomeration and dispersion of landslides on assessments. This issue may cause a systematic evaluation bias when the field investigation data are insufficient, which is common due to limited human resources. Accordingly, this paper proposes two novel strategies, including a clustering algorithm and a preprocessing method, for these two ignored features to strengthen assessments, especially in high-susceptibility regions. Multiple machine learning models are compared in a case study of the city of Bijie (Guizhou Province, China). Then we generate the optimal susceptibility map and conduct two experiments to test the validity of the proposed methods. The primary conclusions of this study are as follows: (1) random forest (RF) was superior to other algorithms in the recognition of high-susceptibility areas and the portrayal of local spatial features; (2) the susceptibility map incorporating spatial feature messages showed a noticeable improvement over the spatial distribution and gradual change of susceptibility, as well as the accurate delineation of critical hazardous areas and the interpretation of historical hazards; and (3) the spatial distribution feature had a significant positive effect on modeling, as the accuracy increased by 5% and 10% after including the spatial agglomeration and dispersion consideration in the RF model, respectively. The benefit of the agglomeration is concentrated in high-susceptibility areas, and our work provides insight to improve the assessment accuracy in these areas, which is critical to risk assessment and prevention activities.

Effects of Landscape Type Change on Spatial and Temporal Evolution of Ecological Assets in a Karst Plateau-Mountain Area.

The rocky desertification control project in karst areas exacerbates the transfer of landscape types, changes the ecosystem structure and function, and has a significant impact on ecological assets. How to analyze the relationship between landscape type shifts and the spatial and temporal evolution of ecological assets is one of the key questions that need to be addressed to achieve the goal of overall improvement in ecosystem quality and sustainable regional economic development. This study takes Qixingguan District, Bijie City, Guizhou Province—a typical karst plateau mountainous area—as the research object, and analyzes the spatial and temporal evolution characteristics of landscape type shifts and ecological assets triggered by rock desertification management from 1995–2018, based on the equivalence factor method, combined with the contribution rate, spatial autocorrelation, and sensitivity research methods. The results showed that arable land, grassland, and woodland were the main landscape types in the study area. The value of ecological assets showed a trend of increasing and then decreasing, with an overall increase of 87.70 × 106 yuan. The distribution pattern of ecological asset value from southwest to northeast is “high–low–high”. There is a significant positive correlation in the spatial distribution of the overall ecological assets, with similar aggregation between neighboring units. The expansion of forest land was the main factor for the rapid increase of assets from 1995 to 2010, with a contribution of 98.12%; the conversion of arable land and grassland to construction land was the main factor for the decrease of assets from 2010 to 2018, with a percentage of 81.06%, where the value of each type of service was mainly composed of five items, such as soil formation and conservation, biodiversity conservation and gas regulation, water conservation, and climate regulation. This study shows that spatial and temporal evolution assessment of ecological assets is an important manifestation of the effectiveness of rocky desertification control, which can provide decision support to resource managers and users for regional ecological environment construction.

Comparison of long-term effects of biochar application on soil organic carbon and its fractions in two ecological sites in karst regions

Biochar (BC) is widely used in soil to increase carbon sequestration. However, the long-term effects of BC application on the soil organic carbon (SOC) and labile organic carbon (LOC) fractions are unclear, especially in karst regions. In order to address this issue, two field experiments were designed to observe the changes in the SOC and its fractions after two years of BC application. In this study, we chose karst regions with two different ecological types, Linquan and Heishitou towns in Bijie City, China. Five BC treatment plots were established, with application rates of 0, 5, 15, 20, and 40 t·ha−1 (CK, B5, B15, B20, and B40, respectively). Compared with CK, the contents of SOC, readily oxidizable organic carbon (ROC), particulate organic carbon (POC) and recalcitrant carbon (RC) under the BC treatments in Linquan increased by 7.09–38.08%, 1.62–39.80%, 9.52–62.30% and 8.66–58.14%, respectively. In Heishitou, the increases in these contents were 3.60–38.58%, 4.40–115.23%, 19.57–50.98% and 10.94–53.87%, respectively. There are significant positive relationships between the SOC content and the ROC, POC and RC contents. However, the application of BC had no significant effect on the DOC content in the two ecological regions. In addition, the soil carbon pool index (CPI) and carbon pool management index (CPMI) increased with increasing BC application rate due to its unique physicochemical properties and nutrients. These results indicate that long-term BC amendment significantly improves the soil quality and carbon sequestration in karst regions by increasing SOC and its LOC fractions.

Upward trends in new, rifampicin-resistant and concurrent extrapulmonary tuberculosis cases in northern Guizhou Province of China

Similar to global trends, the incidence rate of tuberculosis (TB) in China declined from 2000 to 2018. In this study, we aimed to evaluate TB trends in northern Guizhou Province and identify risk factors associated with rifampicin-resistant (RR) and concurrent extrapulmonary TB (EPTB). We analyzed data of TB patients hospitalized in Affiliated Hospital of Zunyi Medical University from 2011 to 2018, and assessed correlations between demographic characteristics of patients and RR-TB as well as concurrent EPTB. Our results showed that numbers of new, retreated, RR-TB and concurrent EPTB cases increased gradually from 2011 to 2018. Retreated patients had the highest odds of RR-TB but a lower likelihood of concurrent EPTB compared to new patients. Patients between 21 and 40 years of age had a higher likelihood of RR-TB compared to those 20 years and younger. Female patients and patients from Bijie city as well as the Miao ethnic minority had higher odds of concurrent EPTB. In summary, our data demonstrate upward trends in new, rifampicin-resistant and concurrent extrapulmonary TB cases in northern Guizhou Province of China, which should not be overlooked especially during and post the COVID-19 pandemic because TB is a greater long-term global health threat than COVID-19.

Detection and Phylogenetic Analysis of a Novel Tick-Borne Virus in Yunnan and Guizhou Provinces, Southwestern China.

Dabieshan tick virus (DTV) is a novel tick-borne virus with the potential to infect both animals and humans. It has been confirmed that DTV is widely distributed in Shandong and Zhejiang Provinces. In this study, a total of 389 ticks were sampled from Honghe city of Yunnan Province and Bijie city of Guizhou Province, and then divided into 148 pools according to the location and species. QRT-PCR and nested PCR were performed to confirm the presence of DTV. The results showed a minimum infection rate of 2.43% (5/206) in Yunnan Province and 3.28% (6/183) in Guizhou Province, respectively. Interestingly, DTV was identified in Rhipicephalus microplus for the first time besides Haemaphysalis longicornis. Phylogenetic analysis showed that DTV from Yunnan and Guizhou Provinces shared over 94% identity with isolates derived from Hubei and Shandong Provinces, and DTV was relatively conservative in evolutionary dynamics. These findings provide molecular evidence of Dabieshan tick virus in different species of ticks from unrecognized endemic regions and suggest that DTV may be widely prevalent in southwestern China.

Study on the Characteristics and Meteorological Causes of Ozone Pollution in Bijie City

Study on the Characteristics and Meteorological Causes of Ozone Pollution in Bijie City

Two new species of the genus Anufrievia Dworakowska from China (Hemiptera: Cicadellidae: Typhlocybinae).

BackgroundThe leafhopper genus Anufrievia Dworakowska, 1970 includes 33 species and is widely distributed in China, Korea, South Korea, Japan, Nepal, India, Thailand and Vietnam.New informationTwo new species found at Bijie City and Shibing County, Guizhou Province, China are described and illustrated, A. crispata sp. nov. and A. confluensa sp. nov. A key to distinguish the Chinese species of the genus is given.

Regional Cooperation Action of Poverty Alleviation by Education in China: Documentary of Pairing Assistance Action in Changxing County, Zhejiang Province

Poverty alleviation by education is the soul of reshaping the development of impoverished areas. In the implementation of poverty alleviation, the collaborative model of impoverished areas driven by developed regions is essential for China’s poverty alleviation work. In 2016, Changxing County, Huzhou City, Zhejiang Province, and Zhijin County, Bijie City, Guizhou Province, established a counterpart support relationship. According to Zhijin County’s education assistance needs, Changxing County has gathered its strength to implement management input, demonstration guidance, and training guidance for its weak schools. With vocational education as the starting point, Zhijin County has been “remodeled” and “implanted” education assistance and has achieved a win-win situation. This article takes the education counterpart support activities of Changxing County and Zhijin County as an example to explore the path and methods of regional education assistance in China under the vision of collaboration.

Biochar Alters Inorganic Phosphorus Fractions in Tobacco-growing Soil

It is important to consider tobacco stalks as sources of biochar and improve the soil quality of tobacco-producing areas in Southwest China. Therefore, in this study, we investigated the effects of biochar produced from tobacco stalks on soil inorganic phosphorus (P) fractions in bulk and rhizosphere soils. We also analyzed the factors influencing these effects in tobacco-planting fields. Biochar was applied to two experimental fields in Heishi and Qianxi in Bijie City, Guizhou Province in China, at application rates of 0, 5, 20, and 40 t ha−1. Subsequently, the soil inorganic P (Pi) fractions, pH, and exchangeable and hydrolytic acidities were analyzed, while the factors influencing the soil Pi fractions were determined by redundancy analysis (RDA). The results indicated that the biochar application rate, experimental site, and tobacco roots all affected the soil Pi fractions. Aluminum-phosphate (Al-P), iron-phosphate (Fe-P), and occluded-phosphate (O-P) levels in the bulk soil had significantly increased with biochar application in the Qianxi site. Meanwhile, there was a reduction in Al-P, Fe-P, and O-P levels in the rhizosphere soil in the Heishi site but not in the Qianxi site. The calcium-phosphate (Ca-P) levels in the soil were also greatly reduced in the Heishi site, while in the Qianxi site, the Ca-P levels were relatively constant in the bulk soil and increased in the rhizosphere soil. Furthermore, the exchangeable and hydrolytic acidities decreased with increasing biochar application. Soil Pi fractions varied according to biochar application rate and experimental site. We found that 20 t ha−1 was an appropriate biochar application rate for enhancing soil Pi fractions. In addition, the soil Pi fractions were negatively correlated with the dissolved organic carbon (DOC) content but were positively correlated with the hydrolytic acidity.

Exploration on the selection of Engineering Project coordinate system based on "Integration of multiple regulations"

In order to avoid the problem that the side length projection deformation value is too large in the process of "multi-gauge in one" coordinate system selection, different coordinate system methods are adopted for planning drawings and engineering construction respectively. In the process of planning, CGCS2000, is comprehensively adopted in the project construction, and the independent coordinate system of the central city of Bijie City is comprehensively adopted. By means of surveying and mapping technology, the connection between the two coordinate systems is established to meet the different needs of the natural resources system and the engineering construction department on a small scale. Under the premise of ensuring the quality and safety of the project construction, it meets the requirements of the Ministry of Natural Resources, and lays a solid surveying and mapping foundation for "multi-regulation integration".

Spatial variation and fractionation of fluoride in tobacco-planted soils and leaf fluoride concentration in tobacco in Bijie City, Southwest China.

Fluorosis is a chronic systemic disease induced by excessive intake of fluoride (F-). Fluoride in water and foods has been widely concerned, while limited reports focused on F- in soils and tobacco leaves which could transfer to human body. In the present study, we mainly focused on the distribution of F- in tobacco-planted soils and tobacco leaves in Bijie City, Southwest China. Soil total F- concentration ranged from 443.7 to 5,979mgkg-1. The level of F- extracted by water (FH2O) and KCl solution (FKCl) ranged from 0.58 to 25.55mgkg-1 and from 0.67 to 21.35mgkg-1, respectively; hence, FH2O could be used to indicate the bioavailability of soil F- in the study area. The sequential extraction of F- show that the residual and exchangeable F- was the highest (97.44-99.73% of the total F-) and lowest (less than 0.25%) fractions of collected soil samples, respectively. According to the distribution of total and soluble F- in the soil profiles at the depth of 0-100cm, soils were polluted mainly at the 0-40cm layer. The soluble F- content in rhizosphere soils were higher than that in bulk soils, and tobacco leaves accumulated F- ranged from 16.73 to 111.3mgkg-1 which was affected by soil pH and Ca content. Tobacco leaves F- level was related to the maturity of the leaves, with the F-content of medium leaves being higher than that of top leaves. More attention should be paid to tobacco with high F- content since F- pollution may transfer to human body via tobacco smoking.

Management of tuberculosis outbreaks in middle schools of Bijie City

Objective To understand the management of tuberculosis outbreaks in middle schools in Bijie City, and to put forward suggestions to improve the quality of tuberculosis epidemic situation in schools. Methods A unified questionnaire was used to investigate the management of tuberculosis outbreaks in middle schools reported by tuberculosis information management system from August 27, 2018 to January 6, 2019 in Bijie City. Results The screening rate of close contacts was 69.72%(99/142), which significantly varied by counties ( P <0.01). The time from the date of diagnosis of patients to screening of close contacts by local CDC was 3 (1-10.5) days. Rate of standardized management process for close contacts aged 15 years or older (0) was lower than that for close contacts aged younger than 15 years old (23.08%) ( P <0.01). 3 462 close contacts were screened for TB symptom, and chest X-ray among those suspected individuals (process 1), and 2 439 close contacts were screened with TB symptom, PPD test, and chest X-ray among those suspected individuals or those with strong positive in PPD test (process 2). The detection rate of pulmonary tuberculosis in close contacts of Grade I was lower in Process 1 (28.89/100 000) than in Process 2 (328.00/100 000) ( χ 2 = 6.56, P = 0.01). The latent infection rate of the first-class close contacts (6.39%) was higher than that of the second-class close contacts (1.93%) ( χ 2 =54.86, P <0.01). Conclusion Management of tuberculosis outbreaks in middle schools in Bijie City in 2018 is effective and timely, but the standardization needs to be improved. 【摘要】 目的 了解毕节市中学结核病疫情处置措施实施情况,为提升学校结核病疫情处置质量提出建议。 方法 采用 统一调查问卷,对毕节市2018年8月27日一2019年1月6日结核病信息管理系统上报的中学肺结核疫情处置情况进行 调查。 结果 密切接触者筛查开展率为69.72%(99/142),不同县（区）间开展率差异有统计学意义（ P <0.01)。患者确诊 之日至属地疾病预防控制机构开展密切接触者筛查工作的时间为3(1〜10.5)d。年龄≥15岁密切接触者的流程规范率 (0)小于<15岁密切接触者(23.08%) ( P <0.01)。3 462名密切接触者开展了症状筛查,发现可疑症状者进行胸片筛查（流 程1);2 439名密切接触者同时进行症状筛查与结核菌素（PPD)试验,对可疑症状者以及PPD强阳性者进行胸片筛查（流 程2)。I级密切接触者筛查肺结核检出率流程1(28.89/10万）小于流程2(328.00/10万）（ χ 2 = 6.56, P =0.01), I 级密切 接触者潜伏感染率(6.39%)大于II级密切接触者（1.93%) ( χ 2 = 54.86, P <0.01)。 结论 毕节市2018年中学结核病疫情处 置开展度较高、较及时,但规范性有待提高。

The Influencing Factors of Bacillus megaterium Affect the Growth of the Antagonistic Strain and the Activities of Antibacterial Substances

164 strains of Antagonistic bacteria were isolated from 131 mature-period soil samples from eight counties in Bijie City, Guizhou Province, China. In this study, the antagonistic bacteria that inhibited Alternaria alternata were screened and isolated. In addition, the antagonistic strain L2 was identified as Bacillus megaterium. Influencing factors also demonstrated that the suitable conditions for the production of antibacterial substances by strain L2 are as follows: liquid volume 50 mL/500 mL at pH 7.0 and 30°C under oscillation culture conditions, with beef extract as the carbon, nitrogen source.

Landslide detection from an open satellite imagery and digital elevation model dataset using attention boosted convolutional neural networks

Convolution neural network (CNN) is an effective and popular deep learning method which automatically learns complicated non-linear mapping from original inputs to given labels or ground truth through a series of convolutional layers. This study focuses on detecting landslides from high-resolution optical satellite images using CNN-based methods, providing opportunities for recognizing latent landslides and updating large-scale landslide inventory with high accuracy and time efficiency. Considering the variety of landslides and complicated backgrounds, attention mechanisms originated from the human visual system are developed for boosting the CNN to extract more distinctive feature representations of landslides from backgrounds. As deep learning needs a large number of labeled data to train a learning model, we manually prepared a landslide dataset which is located in the Bijie city, China. In the dataset, 770 landslides, including rock falls, rock slides, and a few debris slides, were interpreted by geologists from the satellite images and digital elevation model (DEM) data and further checked by fieldwork. The landslide data was separated into a training set that trains the attention boosted CNN model and a testing set that evaluates the performance of the model with a ratio of 2:1. The experimental results showed that the best F1-score of landslide detection reached 96.62%. The results also proved that the performance of our spatial-channel attention mechanism was fairly over other recent attention mechanisms. Additionally, the effectiveness of predicting new potential landslides with high efficiency based on our dataset is demonstrated.

2004-2016年贵州省石漠化状况及动态演变特征

石漠化是制约我国西南地区社会、经济、生态发展的重要因素之一，及时监测评估其演变状况，对区域石漠化防治及生态环境建设具有重要科学意义。选取2004-2016年间4期TM影像，研究贵州省域尺度上、石漠化时空演变特征和未来发展趋势。结果显示：1）2004-2016年间，贵州省78.3%的区域植被覆盖度上升，平均增加了19.1%，达到63.4%，有55.4%的区域岩石裸露率下降；2）贵州省石漠化空间分布呈现从东北到西南渐次加重的特征，西部毕节市中、重度石漠化面积占该区域面积仍达62.0%-86.4%，而东部黔东南州约为18.4%-33.0%；3）2004-2016年间，贵州省石漠化状况呈现总体持续好转态势，以轻、中度石漠化转入为主体的无石漠化面积增加了1.1倍，轻度石漠化增加了20.0%左右，中度和重度石漠化面积分别减少了40.0%左右；4）截止到2016年，贵州省无石漠化、轻、中、重度石漠化区域分别占比约42.0%、24.1%、23.5%、10.4%；5）未来2020年及2024年，贵州省石漠化仍将持续改善，石漠化面积占比将分别减少8.9%和12.2%。过去十多年间，贵州省石漠化状况得到基本遏制，但局部区域仍存在高度的不稳定性，或趋于恶化的风险，未来在各类政策措施的支持下，贵州省石漠化状况仍将继续好转，但部分重度石漠化区域的治理将更为复杂而艰难。;The rock desertification is one of the important factors restricting the development of social, economic and ecology in Southwest China. Timely monitoring and evaluation have great scientific significance for the prevention and control of regional rock desertification and the construction of the ecological environment. In this study, the TM image of four periods from 2004 to 2016 were selected for evaluating the dynamic evolution of rocky desertification in the region of Guizhou Province. The results showed: 1) The vegetation coverage Province went up in 78.3% of Guizhou, with an average of 19.1% to 63.4%, but bare rock rate decreased in 55.4% of this region between 2004 and 2006. 2) The spatial distribution of rocky desertification in Guizhou Province presents the characteristics of gradual aggravation from northeast to southwest. The areas of moderate and severe rocky desertification in Bijie City western Guizhou Province still accounted for 62.0%-86.4%, while in Qiandongnan eastern Guizhou Province, it was only 18.4%-33.0%. 3) From 2004 to 2016, the situation of rocky desertification in Guizhou Province showed a general trend of continuous improvement. The area nil-rocky desertification increased by 1.1 times, deriving from the transition of light and moderate rocky desertification mainly, The slight rocky desertification increased by around 20.0%, and the moderate and severe rocky desertification decreased by around 40.0% respectively. 4) By the end of 2016, the areas of nil-rock desertification, light rock desertification, medium and severe rock desertification in Guizhou Province accounted for about 42.0%, 24.1%, 23.5%, and 10.4% respectively. 5) In 2020 and 2024, the rock desertification would continue to be improved in Guizhou Province, and the areas of rock desertification would decrease by 8.9% and 12.2% respectively. In the past decade or more, the satuation of rock desertification in Guizhou Province has been basically contained, but there was still a high degree of instability or risk of deterioration in some regions. In the future, with the support of various policies and measures, the situation of rock desertification in Guizhou Province will continue to improve, but the controlling of some severe rocky desertification areas will be more complicated and difficult.

Changes in the PM2.5 concentration from 2015 to 2017 in Bijie City, Guizhou Province, China

Atmospheric environmental problems have received more and more attention. Research of PM2.5 has become the core issue of atmospheric environment research. This paper takes the PM2.5 data of the Bijie City from 2015 to 2017 as the research object, and investigates the trend in PM2.5 concentration. The PM2.5 concentration generally showed a decline trend, and the air quality was relatively good. The PM2.5 concentration in Bijie City was basically maintained within the secondary concentration limit of the air environmental quality. The PM2.5 concentration in Bijie City has a weekend effect, and the concentrations on the weekends were slightly higher than those on weekdays. This study can provide a scientific basis for the prevention and control of air pollutants in the Bijie City.

Analysis of main nutrients among different edible parts of ‘Nainaiqingcai’ mustard under the alpine cold climate

Bijie City, Guizhou Province belongs to the alpine cold climate. In order to understand the nutritional values of ‘Nainaiqingcai’ mustard, the contents of main nutrients among different edible parts (leaves, petioles, and bolting stem) in ‘Nainaiqingcai’ mustard under the alpine cold climate were investigated. The results showed that significant differences were found among different edible parts. The levels of chlorophyll, carotenoids, ascorbic acid, soluble soilds, and soluble proteins were followed as the trends of leaves > petioles > bolting stem.Whereas the sugar components showed different distributions, and the lowest content of sugar was detected in leaves. Moreover, significant negatively correlation were found between sugar and the other nutrients. Most of the extremely significant positive correlations were found between sugar components, and the correlation coefficient is high (except for the correlation between fructose and sucrose). The highest correlation coefficient was between chlorophyll and carotenoids, up to 1.000. In summary, the information in this study provides a theoretical reference for the study of nutritional quality of ‘Nainaiqingcai’ mustard under the alpine cold climate.

Screening, Isolating, and Identifying Antagonistic Bacterium from the Rhizosphere Soil of Alternaria Brown Spot

Alternaria brown spot is a serious agricultural fungal disease that consistently leads to serious economic losses in commercial crop fields worldwide. Antagonistic bacteria were isolated from 131 mature-period soil samples from eight counties in Bijie City, Guizhou Province, China. In this study, the antagonistic bacteria that inhibited Alternaria alternata were screened and isolated. In addition, the antagonistic strain L2 was identified as Bacillus megaterium.