Analyzing the influence of land use/land cover change on landscape pattern and ecosystem services in the Poyang Lake Region, China.

The Poyang Lake Region (PLR) is well known for its ecological and economic importance. This paper first analyzed the changes in land use/land cover (LULC), followed by changes in landscape patterns and ecosystem services by landscape metrics and equivalent coefficients table method. Then, the influence of LULC change on landscape pattern and ecosystem services in both historical period (from 1990 to 2015) and future period (2030) was explored. The results showed that the area of construction land was 607.9 km2 in 1990 and 972.5 km2 in 2015. The increased construction land mainly converted from cultivated land. For the entire PLR, a higher use degree of LULC and a trend of fragmentation existed in recent years. The total ecosystem service values (ESVs) decreased by ¥2.44 × 109 from 1990 to 2015, mainly because of shrinkage of cultivated land and sharp increase in construction land. It was predicted that the areas of construction land and waterbody would increase by 34.6% and 2.2% compared with those in 2015. These changes would lead to more regular in patch shape, longer in patch edge, less connectivity of patches, and an increase of ¥6.2 × 108 ESVs in 2030.

Spatiotemporal patterns of the trade-off and synergy relationship among ecosystem services in Poyang Lake Region, China.

Poyang Lake region is the largest freshwater lake impacted area in China. Quantitative analysis of trade-off and synergy in ecosystem service is of great significance for realizing regional sustainable development. Based on multi-source data of remote sensing, soil, meteorology and DEM, we quantitatively measured food supply service, soil conservation service and water yield service in Poyang Lake region from 2005 to 2015, and analyzed their spatiotemporal patterns and evolution characteristics. The spatial and temporal characteristics of trade-off and synergy between services on the scale of 1 km×1 km were analyzed by using correlation analysis, hot spot analysis and spatial mapping method. The differences of ecosystem services and their relationships in the perspective of land use were studied. The results showed that food supply service increased, soil conservation service decreased, and water yield service increased first and then decreased during the study period. In terms of spatial distribution, food supply service presented "low-high-low-high" in the northwest-southeast direction, soil conservation service was concentrated in high and low values, and water yield service was high in south and low in north. There were trade-off relationships between food supply and soil conservation, and between food supply and water yield. There was synergistic relationship between soil conservation and water yield. Moreover, the relationship between food supply and soil conservation showed a spatial pattern of synergy in northern but trade-off in southern region. There was a clear spatial trade-off between food supply and water yield, and from north to south the relationship between soil conservation and water yield existed synergy-tradeoff-synergy differentiation, like a "sandwich". Among different land use types, there was a significant synergy between cultivated land and food supply, garden land and soil conservation, water area and water yield, but trade-off relationships between construction land and three services. The relationship between food supply and soil conservation and water yield was mainly trade-off in different land use types. The relationship between soil conservation and water yield was synergy in cultivated land, garden land, grassland and construction land, but was trade-off in water and unused land. The hot spots of multiple ecosystem services in the Poyang Lake region were mainly in the eastern and sou-thern plain areas, with a decreasing trend.

[Basic soil productivity in the double rice cropping system under long-term fertilization regimes in the Poyang Lake region, China]. / 鄱阳湖流域长期施肥下双季稻田的土壤基础地力.

We aimed to explore changes in basic soil productivity (BSP) under different fertilization regimes in the Poyang Lake region, Jiangxi Province, China. Soil samples were collected from a long-term fertilization experiment (since 1981) that included treatments of no fertilization (CK), chemical fertilization (NPK), and combined chemical and organic fertilization (NPKM). Then, a three-year pot experiment (from 2012 to 2014) with double rice cropping was conducted with two different fertilization regimes (no fertilization, F0; fertilization, F1) using CK, NPK and NPKM soils. Grain yield and BSP were analyzed among soils with different fertilization regimes to identify the key factors driving changes in BSP. Results showed that grain yields in NPKM soil were higher than in NPK and CK soils regardless of fertilization in the pot experiment. Under the F0 condition, annual grain yields of NPKM soil were 37.7%-143.9% and 20.8%-66.7% higher than CK and NPK soils, respectively. The BSP values of CK, NPK and NPKM soils in three years were 41.8%-53.1%, 45.2%-62.6% and 59.1%-88.1%, respectively. NPKM soil had significantly higher BSP than NPK and CK soils. Furthermore, there were significant positive correlations between soil organic matter and BSP as well as between organic carbon balance and BSP. These results suggested that long-term application of chemical and organic fertilizers could improve BSP in the double rice cropping system of the Poyang Lake region. In addition, soil organic matter and organic carbon balance are important factors for improving BSP in this region.

Tick-Borne Pathogens in Ixodid Ticks from Poyang Lake Region, Southeastern China.

Ticks are the vectors of various pathogens, threatening human health and animal production across the globe. Here, for the first time we detected Ricketssia spp., Borrelia spp. and protozoan in ticks from Poyang Lake region in Ji- angxi Province of eastern China. In 3 habitat categories and on 12 host species, 311 ticks from 11 species were collected. Haemaphysalis longicornis was the predominant species, accounting for 55.63%, followed by Rhipicephalus microplus, Haemaphysalis flava and Ixodes granulatus. Of the collected ticks, 7.07% were positive for tick-borne pathogens, and H. longicornis and H. flava were found to be co-infected with Ricketssia spp. and protozoan. H. flava was the most detected positive for tick-borne pathogens, whereas H. longicornis had the lowest infection rate, and the difference in infection rates between tick species was significant (χ2=61.24, P<0.001). Furthermore, adult ticks demonstrated remarkably greater infection rate than immature ticks (χ2=10.12, P=0.018), meanwhile ticks on Erinaceidae showed significantly higher positivity than ticks collected on other host species (χ2=108.44, P<0.001). Genetic fragment sequencing and analyses showed at least 4 pathogen species presence in ticks, namely Borrelia yangtzensis, Rickettsia slovaca or Rickettsia raoultii related genospecies, Babesia vogeli and Hepatozoon canis or Hepatozoon felis related genospecies. The finding indicates that the abundant ticks can carry diverse pathogens in Poyang Lake region, and pathogen infection is highly related to species, vertebrate hosts and life stages of ticks.

Tick-Borne Pathogens in Ixodid Ticks from Poyang Lake Region, Southeastern China

Ticks are the vectors of various pathogens, threatening human health and animal production across the globe. Here, for the first time we detected Ricketssia spp., Borrelia spp. and protozoan in ticks from Poyang Lake region in Jiangxi Province of eastern China. In 3 habitat categories and on 12 host species, 311 ticks from 11 species were collected. Haemaphysalis longicornis was the predominant species, accounting for 55.63%, followed by Rhipicephalus microplus, Haemaphysalis flava and Ixodes granulatus. Of the collected ticks, 7.07% were positive for tick-borne pathogens, and H. longicornis and H. flava were found to be co-infected with Ricketssia spp. and protozoan. H. flava was the most detected positive for tick-borne pathogens, whereas H. longicornis had the lowest infection rate, and the difference in infection rates between tick species was significant (χ²=61.24, P < 0.001). Furthermore, adult ticks demonstrated remarkably greater infection rate than immature ticks (χ²=10.12, P=0.018), meanwhile ticks on Erinaceidae showed significantly higher positivity than ticks collected on other host species (χ²=108.44, P < 0.001). Genetic fragment sequencing and analyses showed at least 4 pathogen species presence in ticks, namely Borrelia yangtzensis, Rickettsia slovaca or Rickettsia raoultii related genospecies, Babesia vogeli and Hepatozoon canis or Hepatozoon felis related genospecies. The finding indicates that the abundant ticks can carry diverse pathogens in Poyang Lake region, and pathogen infection is highly related to species, vertebrate hosts and life stages of ticks.

Village-based spatio-temporal cluster analysis of the schistosomiasis risk in the Poyang Lake Region, China.

BACKGROUND: The Poyang Lake Region, one of the major epidemic sites of schistosomiasis in China, remains a severe challenge. To improve our understanding of the current endemic status of schistosomiasis and to better control the transmission of the disease in the Poyang Lake Region, it is important to analyse the clustering pattern of schistosomiasis and detect the hotspots of transmission risk. RESULTS: Based on annual surveillance data, at the village level in this region from 2009 to 2014, spatial and temporal cluster analyses were conducted to assess the pattern of schistosomiasis infection risk among humans through purely spatial (Local Moran's I, Kulldorff and Flexible scan statistic) and space-time scan statistics (Kulldorff). A dramatic decline was found in the infection rate during the study period, which was shown to be maintained at a low level. The number of spatial clusters declined over time and were concentrated in counties around Poyang Lake, including Yugan, Yongxiu, Nanchang, Xingzi, Xinjian, De'an as well as Pengze, situated along the Yangtze River and the most serious area found in this study. Space-time analysis revealed that the clustering time frame appeared between 2009 and 2011 and the most likely cluster with the widest range was particularly concentrated in Pengze County. CONCLUSIONS: This study detected areas at high risk for schistosomiasis both in space and time at the village level from 2009 to 2014 in Poyang Lake Region. The high-risk areas are now more concentrated and mainly distributed at the river inflows Poyang Lake and along Yangtze River in Pengze County. It was assumed that the water projects including reservoirs and a recently breached dyke in this area were partly to blame. This study points out that attempts to reduce the negative effects of water projects in China should focus on the Poyang Lake Region.

Study on immune status of patients with schistosomiasis japonica in Poyang Lake region Ⅲ Humoral and cellular immune characteristics between Schistosoma ja-ponicum high and low antibody responders / 中国血吸虫病防治杂志

Objective To explore the immune mechanism of negative results of immune tests of schistosomiasis japonica pa?tients. Methods Totally 142 schistosomiasis patients(positive stool examinations)of Poyang Lake region were tested by ELI?SA method,and the ROC curve was applied to determine the high and low response of the patients. The levels of cellular immu?nity and cytokines of high and low responders were compared. Results Totally eight schistosomiasis patients were found as low responders. Besides SWAP?IgA(t= -1.588,P > 0.1),the levels of isotype antibodies were significantly lower in the low re?sponders compared with those in the high responders(t = -14.517 to -2.866,all P 0.05)compared with those in the high responders. The differences of IFN?γ and IL?10 between the high and low responders were both not significant(t= -2.426 to 0.216,all P >0.05). Conclusions There is a significant difference between the high and low responders only in the levels of isotype antibod?ies. One of the reasons of low response in the immune tests is the much lower antibody level after the antigen?antibody compound is completely formulated.

Natural environment and schistosomiasis transmission in Poyang Lake re-gion / 中国血吸虫病防治杂志

Schistosomiasis is closely related to natural environmental factors. The changes of environmental factors such as temperature hydrology vegetation soil etc. all impact the scope and extent of schistosomiasis transmission. Poyang Lake is the largest freshwater lake and one of the major endemic areas with schistosomiasis in China. With global warming the imple-mentation of the Three Gorges Dam operation and the Poyang Lake Ecological Economic Planning the natural environment in Poyang Lake area has been and will continue to change especially the water environment and climate environment which are more closely related to the schistosomiasis transmission. These changes to some extent have affected and will continue to affect the prevalence and transmission of schistosomiasis. This article reviews the relationship between the natural environment and its changes and schistosomiasis transmission in the Poyang Lake region.

Seasonal dynamics of Schistosoma japonicum infection in buffaloes in the Poyang Lake region and suggestions on local treatment schemes.

Schistosomiasis japonica remains a major public health problem and the Poyang Lake region in Jiangxi province is one of the worst affected endemic areas. Buffaloes play a major role in the transmission of Schistosoma japonicum to humans. The aim of the present study was to increase understanding of the epidemic characteristics of schistosomiasis japonica in water buffaloes in the Poyang Lake region, after achieving the national mid-term goal, and to provide a basis for further interventions. The baseline prevalence in two villages in the Poyang Lake region in May 2010 was compared with respect to usage, sex and age in the total study population. Seasonal dynamics from May 2010 to May 2011 were observed in a natural village in the studied area. The baseline prevalence of infection in both villages (Caohui and Gaozhou) was 4.94% in May 2010. The prevalence in buffalo younger than 12 months was 12.82% in Caohui and 15.11% in Gaozhou, which was significantly higher than that found in those aged 13-24 months and older than 24 months. Of the 28 infected buffaloes, 82.14% (23) were younger than 12 months. The flow of seasonal dynamics showed that S. japonicum infection buffaloes were found from May to July and from November to January of the following year. This survey suggested that it is necessary to conduct two mass treatments (especially for young animals) in late March or early April and November, with an additional treatment of positive animals in July or June.

Endemic situation of schistosomiasis in Tangyin Village of Duchang County, Poyang Lake region / 中国血吸虫病防治杂志

The endemic situation of schistosomiasis in Tangyin Village of Duchang County from 2000 to 2007 showed the infection rates of residents between 2003 and 2007 were all around 10%.In 2000.2002 and 2007,the infection rates of snails were 0.32%,O.45%and 0.38%,respectively,and the densities of infected snails were 0.016,0.004 No./0.1 m~2.and 0.004 No./0.1 m~2,respectively.It is suggested that the snail control and health education should be strengthened and the self-protection awareness of residents should improve for schistosomiasis control.

Utrasonographical characters of liver and spleen of residents due to Schistosoma japonicum infection and their changes in Poyang Lake region, Jiangxi Province / 中国血吸虫病防治杂志

Objective To observe the uhrasenographical characters of liver and spleen of residents and their changes in endearic areas of schistosomiasis japonica in Poyang Lake region.Jiangxi Province and to explore the value of ultrasonography for assessment of the morbidity of the disease.Methods All permanent residents aged above 3 years old were examined by ultrasonography and Kato-Katz method.Results The schistosome positive rates of fecal examinations decreased obviously from 16.29%in 1995 to 8.54%in 2007(P0.05),with the rates of 8.82% and 20.33% in 1995 and 8.54% and 21.34% in 2007,respectively.The abnormal rate of portal vein diameter decreased significantly.from 32.47%in 1995 to 6.50% in 2007.The abnormal rate of liver parenehyma increased remarkably(P<0.01),from 34.85% to 51.83%.The changes of liver parenchyma Grade I showed a bidirectional trend,29.90% of them chased into Grade 0(normal image on ultrasonngraphy),and 34.02% changed into Grade 2 and above.The abnormality of various indices of uhrasonography examinations were related to age,occupation and schistesome infection status.Conclusions Ultrasonography can show the damages of liver and spleen of patients infected with Schistosoma japonicum directly.but it is necessary to study further on the sensitive indices that reflecting early pathological changes and the best combination of the indices for the assessment of schistosomiasis-related morbidity.

Application of GPS in snail survey of Poyang Lake region / 中国血吸虫病防治杂志

GPS was used in the snail survey of Nuanhuping marshland in Poyang Lake region and its application value was discussed. The results suggest that GPS which can measure the marshland area and survey area at real-time and draw electronic maps of snail situation rapidly, could realize the electronic and image management of the data from snail survey and provide more accurate information to the department in charge of schistosomiasis control.