The role of biocrusts in nitrogen cycling on the tropical reef islands,South China Sea

Harboring polyextremotolerant microbial topsoil communities,biological soil crusts(biocrusts)occur across various climatic zones,and have been well studied in the terrestrial drylands.However,little is known about the functional metabolic potential of microbial communities involved in the biogeochemical processes during the early succession of biocrusts on the tropical reef islands.We collected 26 biocrusts and bare soil samples from the Xisha Islands and Nansha Islands,and applied a functional gene array(GeoChip 5.0)to reveal nitrogen(N)cycling processes involved in these samples.Both physicochemical measurement and enzyme activity assay were utilized to characterize the soil properties.Results revealed the composition of N-cycling functional genes in biocrusts was distinct from that in bare soil.Additionally,microorganisms in biocrusts showed lower functional potential related to ammonification,denitrification,N assimilation,nitrification,N fixation,and dissimilatory nitrate reduction to ammonium compared to bare soils.Although the abundance of nifH gene was lower in biocrusts,nitrogenase activity was significantly higher compared to that in bare soils.Precipitation,soil physicochemical properties(i.e.,soil available copper,soil ammonia N and pH)and soil biological properties(i.e.,β-glucosidase,fluorescein diacetate hydrolase,alkaline protease,urease,alkaline phosphatase,catalase and chlorophyll a)correlated to the N-cycling functional genes structure.Nitrate N and ammonia N were more abundant in biocrusts than bare soil,while pH value was higher in bare soil.Our results suggested biocrusts play an important role in N-cycling in coral sand soil,and will be helpful in understanding the development and ecological functions of biocrusts on tropical reef islands.

Vegetable Tunnel House Technology in Tropical Island Countries

A complete set of techniques for the design,installation,maintenance and use of vegetable tunnel houses in tropical island countries was developed,which achieved the goals of rain prevention,wind protection,corrosion resistance,insect and bird prevention,water-saving irrigation,and economic efficiency,significantly improving the production capacity and technical level of vegetables in Samoa.The techniques have become a key vegetable production technology promoted nationwide in Samoa,with universal promotion value for tropical island countries.

Season modulates endocrinological profiles and sex behavioural characteristics in indigenous male goats under tropical humid island ecosystem

Objective:To measure the seasonal effect on endocrinological profiles and sex behavioural profiles during rainy and dry summer seasons in male Andaman local goat in Andaman and Nicobar Islands,India.Methods:Ten adult male Andaman local goats were selected from the goat breeding farm,ICAR-Central Island Agricultural Research Institute,Port Blair,Andaman and Nicobar Islands,India.Endocrinological profiles such as follicle stimulating hormone(FSH),luteinizing hormone(LH),testosterone,thyroid stimulating hormone(TSH),triiodothyronine(T3),thyroxine(T4),cortisol and prolactin were analysed with enzyme-linked immunosorbent assay kits.Sex behavioural profiles such as libido score,mating ability score and sex behavioural score were measured during rainy and dry summer seasons in male Andaman local goat.Results:Endocrinological profiles as well as sex behavioural profiles differed significantly between rainy season and dry summer season(P<0.05).The levels of FSH,LH,testosterone,TSH,T3,and T4 were significantly higher in rainy season than in dry summer season whereas cortisol and prolactin were significantly higher in dry summer season than in rainy season(P<0.05).The ratio of T3:T4 was significantly higher in rainy season than in dry summer season.Similarly,libido score,mating ability score and sex behavioural score were significantly higher in rainy season than in dry summer season(P<0.05).Conclusions:Rainy season has significantly higher beneficial effects than summer season on reproduction and artificial breeding programmes in semi-intensive management of goat under the tropical humid island ecosystem in Andaman and Nicobar Islands.

Tropical Hainan——China’s Hawaii

BEFORE moving to China,my favorite hideaway was Hawaii,so I was delighted to learn China has its own Hawaii–southernmost Hainan Province.A Han Dynasty(206 BC-AD 220)emperor established a military garrison on Hainan Island,the largest island of Hainan Province,in 110 BC.Sun Yatsen recommended the establishment of a province in the region in 1906,but this did not happen until 1988,the year we moved to China.

Differential expression analysis of coronary heart disease related genes in Hainan residents

Objective:To explore the correlation between coronary heart disease related genes and coronary heart disease in hospitalized patients in Hainan,and to provide theoretical basis for enriching the screening methods of high-risk groups of coronary heart disease in Hainan,and optimizing the prevention and treatment strategies.Methods:We select hospitalized patients born in Hainan and aged>30 years old from the Second Affiliated Hospital of Hainan Medical Unversity between January 1,2020 and June 30,2022,and divided the patients into the coronary heart disease group and the non-coronary heart disease group.PCR real-time fluorescence was used to measure gene expression,and Spearman correlation analysis was used to explore the correlation between gene expression and coronary heart disease.Results:A total of 55 whole blood samples were collected from non-coronary heart disease patients(including 26 women and 29 men),with a median age of 57 years,and 170 whole blood samples from coronary heart disease patients(including 44 women and 126 men),with a median age of 63.17.Apolipoprotein B gene(ApoB)was highly expressed in patients with coronary heart disease(P<0.001);AGT gene(P=0.0158),ApoE gene(P=0.0126),FGB gene(P=0.005),GNB gene(P=0.0151),MTFHR gene(P=0.0119),SEL gene(P=0.005),TNF gene(P=0.0298)were significantly overexpressed in the non-coronary heart disease group.The expression of NOS3 gene(P=0.3047),IL6 gene(P=0.7239),ACE gene(P=0.7852)was not different between the two groups.Coronary heart disease was negatively correlated with AGT gene(r=-0.163,P=0.011,P<0.05),positively correlated with APOB gene(r=0.75,P=0,P<0.01),negatively correlated with FGB gene(r=-0.163,P=0.011,P<0.05),negatively correlated with GNB gene(r=-0.165,P=0.011,P<0.05),negatively correlated withSEL gene(r=-0.171,P=0.007,P<0.01),negatively correlated with MHTHR gene(r=-0.210,P=0.001,P<0.01)and negatively correlated with TNF gene(r=-0.131,P=0.04,P<0.05),but coronary heart disease was not correlated with APOE,NOS3,ACE,IL6 and other genes(P>0.05).The ApoB gene of coronary heart disease was negatively correlated with triglyceride(r=-0.461,P=0),positively correlated with age(r=0.173,P=0.009),positively correlated with total cholesterol(r=0.499,P=0),negatively correlated with high-density lipoprotein(r=-0.181,P=0.007),and negatively correlated with low-density lipoprotein(r=-0.143,P=0.031).Conclusion:(1)The detection of apolipoprotein B gene expression may be used as an indicator for screening coronary heart disease in the coronary population in Hainan.It may increase the risk of coronary heart disease by affecting the level of total cholesterol.A larger sample of research is still needed.(2)AGT,ApoE,FGB,GNB,MTFHR,SELE,TNF and other genes may be the protective genes of non-coronary heart disease population in Hainan,and the high expression of these genes may reduce the occurrence of coronary heart disease,which still needs further study.