[Responses of the spatial distribution of Stipa breviflora to stocking rate at different scales.] / ä¸åŒå°ºåº¦ä¸‹è’æ¼ è‰åŽŸå»ºç¾¤ç§çŸ­èŠ±é’ˆèŒ çš„ç©ºé—´åˆ†å¸ƒå¯¹è½½ç•œçŽ‡çš„å“åº”.

We conducted an experiment to test the characteristics and differences of the spatial distribution of constructive species Stipa breviflora at different scales under different stocking rates in the S. breviflora desert steppe in Siziwang Banner, Inner Mongolia. The spatial distribution of S. breviflora under four treatments (control, light grazing, moderate grazing, and heavy grazing) at different scales (small scale as 1 m×1 m and mesoscale as 5 m×10 m) were analyzed. The results showed that the population density of S. breviflora at mesoscale in the control and light grazing was significantly lower than that at the small scale. Grazing significantly increased the population density of S. breviflora in the meso- and small scales. At the small scale, the population distribution of S. breviflora in the control, light grazing, moderate grazing, and heavy grazing treatments conformed to linear, exponential, exponential and exponential models, respectively, and Gaussian, exponential, Gaussian and exponential models at mesoscale fitted by semi-variance function. The spatial distribution pattern at small scales in the control was simple and better but was more complex and poorer under the heavy grazing. At the mesoscale, it was simple and better under the heavy grazing but complex and poor under the moderate grazing. The spatial heterogeneity of S. breviflora population reduced and were more uniform under the moderate and heavy grazing at meso- and small scales. In addition, the trend of population distribution in the enclosure, moderate and heavy grazing were generally the same, while light grazing showed inconsistent trend at different scales.

[Effects of mowing height on community structure and stability in Stipa grandis steppe]. / åˆˆå‰²ç•™èŒ¬é«˜åº¦å¯¹å¤§é’ˆèŒ è‰åŽŸç¾¤è½ç»“æž„åŠç¨³å®šæ€§çš„å½±å“.

We examined the effects of mowing height on community structure and stability in August from 2014 to 2018 in a Stipa grandis steppe of Xilingol, Inner Mongolia, China. Three mowing height treatments (2, 5 and 8 cm) were manipulated, with enclosure as the control. Results showed that 27 species from 23 genera of 15 families were recorded in the community. The community was dominated by S. grandis, Anemarrhena asphodeloides, Leymus chinensis and Cleistogenes squarrosa. The cumulative relative importance value of those four species was 76.1%. Of all species, there were 15 perennial forbs, 5 annuals biennials, 3 perennial bunch grasses, 3 shrubs semi-shrubs, and 1 perennial rhizome grasses. S. grandis was in the upper layer of the community, L. chinensis and A. asphodeloides were in the middle layer, C. squarrosa, Chenopodium aristatum and Salsola collina were at the bottom layer. Mowing decreased the relative importance value (RIV) of S. grandis and perennial bunch grasses, but increased that of C. squarrosa, C. aristatum, S. collina and annuals biennials. The RIV of L. chinensis was decreased in the 2 cm treatment but increased in the 5 cm and 8 cm treatments. The RIV of A. asphodeloides was increased in the 5 cm treatment but decreased in both the 2 cm and 8 cm treatments. The RIV of perennial forbs was decreased in the 8 cm treatment but increased in both the 2 cm and 5 cm treatments. Species and functional groups diversity showed significant interannual variation. Generally, species richness and diversity were little affected by mowing, while functional groups diversity was significantly impacted, indicating that compensation between different functional groups would stabilize the community under mowing. Mowing increased community stability. Community stability was higher in the 5 cm and 8 cm treatments, with the variability being larger in the 5 cm than in the 8 cm treatment. Therefore, the 8 cm treatment was beneficial for the stability and sustainable utilization of grassland community.

[Effects of grazing intensity on spatial heterogeneity of the constructive species Stipa breviflora in desert steppe.] / æ”¾ç‰§å¼ºåº¦å¯¹è’æ¼ è‰åŽŸå»ºç¾¤ç§çŸ­èŠ±é’ˆèŒ ç©ºé—´å¼‚è´¨æ€§çš„å½±å“.

This study evaluated the changes of spatial distribution of the constructive species Stipa breviflora in the desert steppe under different grazing intensities (control, light, moderate, and heavy grazing) in Siziwang, Inner Mongolia. The small-scale spatial distribution of S. breviflora was measured. Results showed that population density of S. breviflora was following the order: heavy grazing (27.81 individuals·m-2) > moderate grazing (22.17 individuals·m-2) > control (11.31 individuals·m-2) > light grazing (10.76 individuals·m-2). The moderate and heavy grazing significantly increased population density of S. breviflora. According to the model fitting by semi-variance function, the population density of S. breviflora under the control, light, moderate and heavy gra-zing treatments were consistent with the exponential model, spherical model, exponential model and spherical model, respectively. Results from spatial distribution pattern analysis showed that structural ratio of S. breviflora population was control (99.7%) > heavy grazing (94.7%) > light grazing (92.7%) > moderate grazing (87.9%). Such a result indicated that the spatial autocorrelation of the four treatments was high, which were mainly affected by structural factors. In comparison, S. breviflora population structure ratio under moderate grazing treatment was the smallest, and partly affected by random factors. Based on fractal dimension analysis, spatial structure of the four treatments was good with simple spatial distribution. With the increases of grazing intensity, the spatial distribution was simpler and more homogeneous. Combined with 2D and 3D views, both light and heavy grazing changed spatial distribution of S. breviflora population from gradient distribution to patch distribution and resulted in the reduction of spatial heterogeneity.

[High-risk behaviors related to AIDS/STDs infections among fishermen in Lü-si harbor, Jiangsu province].

OBJECTIVE: To investigate the high-risk behaviors related to acquired immune deficiency syndrome/sexually transmitted disease (AIDS/STDs) infection among fishermen in Lü-si harbor, Jiangsu province. METHODS: A cross-sectional study was designed to investigate the research participants' demographic characteristics, high-risk behaviors that related to AIDS/STDs. Logistic regression was performed to measure the associations between potential risk factors and reported potential high-risk sexual behavior. RESULTS: 817 fishermen participated in the study and casual or commercial sex activities appeared to be the main high-risk behavior for AIDS/STDs infection in the target population. The rates of casual and commercial sex reported were 18.1% and 28.9% among fishermen. Risk factors associated with AIDS/STDs related high-risk behaviors among fishermen were high mobility (OR = 1.516, P = 0.038), higher lifetime sex frequency (OR = 1.422, P = 0.002) and unmarried status (OR = 7.527, P = 0.014). Protective factors against high-risk behaviors were low intake of alcohol (OR = 0.803, P = 0.053), negative STD history (OR = 0.268, P = 0.001), age of initial sexual intercourse at or older than 22 years (OR = 0.440, P = 0.000) of age, as well as negative attitude toward multiple sexual partners (OR = 0.662, P = 0.023) and legitimation for commercial sex (OR = 0.612, P = 0.007). CONCLUSION: There were risk behaviors of AIDS/STDs in those infected fishmen. Casual and commercial sex were common high-risk behaviors.

[Analysis of imported falciparum malaria cases of Nantong City from 2001 to 2010].

OBJECTIVE: To analyze the characteristics of imported falciparum malaria cases of Nantong City in the recent ten years so as to provide the evidence for improving prevention and control of malaria in the future. METHODS: The data about imported falciparum malaria cases of Nantong City from 2001 to 2010 were collected and analyzed for the characteristics and distribution of the patients by the retrospective method. RESULTS; There were 79 imported falciparum malaria cases in the last 10 years. Totally 96.2% of patients were infected in Africa. Most of them were young people and worked for the construction services. Seasonal distribution difference was not obvious. CONCLUSIONS; The imported falciparum malaria epidemic is rising in Nantong City. Therefore, we should strengthen the anti-malaria health education to increase the self-protection of labors, and strengthen the training of medical stuff and also strengthen the monitoring of malaria epidemic.

[A related heredity epidemiological research on allergic rhinitis and asthma in Nantong region].

OBJECTIVE: To discuss the related impact of genetic factors in the incidence of bronchial asthma (BA) and allergic rhinitis (AR) in Nantong region, China. METHODS: By random sampling method, investigation and research on the incidence of genetic epidemiology were carried out in the population of 95 300 on AR and BA. RESULTS: The rate of patients with allergic rhinitis with asthma was 25.92% (296/1142), the rate of asthma patients with allergic rhinitis was 40.49% (296/731). The prevalences of AR complicated with BA were 8.19% (280/3418), 3.08% (154/5002) and 3.16% (85/2687) in the first-, second-and third-degree relatives of the probands respectively, while the prevalences of BA complicated with AR were 15.81% (466/2947), 4.61% (229/4967) and 2.51% (134/5345) in the first-, second- and third-degree relatives of the probands respectively, higher than those in the controls (P < 0.05). The weighted mean heritability of AR in BA patients was 94.2% ± 1.9%, while the weighted mean heritability of BA in AR patients was 81.8% ± 2.1%, more than 60%, suggesting that both AR and BA were relevant with genetics. CONCLUSIONS: The incidence of BA and AR has obvious relevance, supporting the theory that the two diseases are an united airway disease and relevant with polygene heredity.

[Genetic epidemiological study on allergic rhinitis in Nantong region of Jiangsu Province].

OBJECTIVE: To explore the effects of genetic factors on the occurrence of allergic rhinitis (AR). METHODS: The morbidity rate of AR was surveyed by multistage sampling among 95 300 individuals (23,825 families) in Natong region, Jiangsu province. And a genetic epidemiologic investigation on AR was carried out to estimate the segregation ratio and heritability (h2) of AR by the methods of Li-Mantel-Gart and Falconer respectively. RESULTS: The morbidity rate of AR in Natong region was 1.20% (Male 1.21%, Female 1.18%, no statistical significance between them); By the data of the AR ancestry, the segregation ratio of AR in Nantong region was 0.078, significantly less than 0.25, and the genetic model belonged to polygenetics. The 1st, the 2nd, and the 3rd generation h2 of AR were (82.6 +/- 2.19)%, (80.8 +/- 2.93)%, (78.4 +/- 7.04)%. The h2 of AR was (81.86 +/- 1.70)%. In the ancestry of AR, the morbidity rate of the 1st generation with AR was 12.11%; the 2nd generation with AR was 5.12%; the 3rd generation with AR was 2.75%; and the morbidity rate of AR in general population was 1.20%. CONCLUSIONS: The heredity in family with AR is obvious. Several genes plus the environmental factors may cause AR, which accords with the characteristics of the polygene heredity disease.