文献类型：期刊文献

英文题名：Afforestation suppresses Oncomelania hupensis snail density through influencing algae in beaches of the Dongting Lake

作者：Yang, Xiao[1,2,3,4] Zhang, Qian[5] Ma, Li[1,3,4] Sun, Qi-Xiang[5] Liang, Song[6,7] Zhou, Jin-Xing[1,3,4]

第一作者：Yang, Xiao

通信作者：Zhou, JX[1];Zhou, JX[2];Zhou, JX[3]

机构：[1]Beijing Forestry Univ, Sch Soil & Water Conservat, Beijing, Peoples R China;[2]Natl Forestry & Grassland Adm, Acad Forest Inventory & Planning, Beijing, Peoples R China;[3]Key Lab State Forestry Adm Soil & Water Conservat, Beijing, Peoples R China;[4]Minist Educ, Engn Res Ctr Forestry Ecol Engn, Beijing, Peoples R China;[5]Chinese Acad Forestry, Inst Forestry, Beijing, Peoples R China;[6]Univ Florida, Coll Publ Hlth & Hlth Profess, Dept Environm & Global Hlth, Gainesville, FL USA;[7]Univ Florida, Emerging Pathogens Inst, Gainesville, FL USA

年份：2021

卷号：15

期号：2

外文期刊名：PLOS NEGLECTED TROPICAL DISEASES

收录：;Scopus(收录号：2-s2.0-85102212551);WOS:【SCI-EXPANDED(收录号:WOS:000616720900002)】；

基金：X.Y., J-X. Z and L.M. was funded by the National Science and Technology Support Program of China (grant No. 2015BAD07B07). Q.Z. and Q-X. S. was funded by the National Natural Science Foundation of China (NSFC) (grant No. 41071334). S.L. was supported in part by the National Institutes of Health (grant R01AI125842) and a grant from the World Health Organization. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

语种：英文

摘要：Author summary Schistosomiasis is the second largest tropical parasitic disease in the world after malaria. By the end of 2018, the areas in which schistosomiasis is endemic in China are distributed across 12 provinces (municipality and autonomous region). Among these areas, 5 provinces, including Shanghai, Zhejiang, Fujian, Guangdong and Guangxi, have continued to consolidate achievements in schistosomiasis elimination. Sichuan Province has achieved transmission interruption and 6 provinces of Hunan, Hubei, Anhui, Jiangxi, Yunnan, Jiangsu have achieved transmission control. Oncomelania hupensis (Snail) is the only intermediate host for the parasite schistosomiasis japonicum, so snail control is an important measure to control the spread of schistosomiasis. So far, the area the snail inhabits in China is 3.63 billion m(2), with more than 95% of this distributed along the beaches of Yangtze River. Forestry schistosomiasis prevention projects has effectively reduced the snail habitat area and decreased snail population density through afforestation of these areas in China. However, the key factors that inhibit snail population growth by afforestation remain unclear. We propose to investigate the interactional relationship between biotic and abiotic factors introduced by afforestation on the distribution of the snail population. The results revealed that the number of soil algae is the important biological element determining snail distribution. Abiotic factors, such as soil properties indirectly impact on the snail population through a direct influence on soil algae. Of these, the pH value, water content, capillary porosity, bulk density interact with the algae content (Chlorophyta, Cyanophyta and Bacillariophyta) to decrease snail density through afforestation. Background Oncomelania snails serve as the sole intermediate host for Schistosoma japonicum, one of the most important neglected tropical diseases in the world. Afforestation suppression of the Oncomelania hupensis snail has been a long-term effective national strategy to decrease snail density in China. Many previous studies have made clear that vegetation (biotic factors) and soil (abiotic factors) were the basic requirements for snail survival on beaches. Moreover, a lot of research on snail control has been focused on the specific influencing environmental factors for snail survival, such as the vegetation community structure, species composition, diversity index, and the physical and chemical properties of the soil. Most of the existing research has studied the influence of a single factor on snail population density. Conversely, there have been only a few studies focused on the food sources and food composition of the snails. The current research situation on snail control has indicated that the mechanisms underlying ecological snail control have not been systematically characterized. The question of whether biotic or abiotic factors were more important in influencing snail survival remains unclear. Afforestation on beaches has significantly suppressed snail density in China so far. In this study, we proposed that the reduction of snail density was not affected by a single factor but by the interactions of multiple related factors introduced by afforestation. Moreover, different biotic and abiotic factors have significantly different effects on snail control. Therefore the goal of this study was to evaluate the relative importance and interactions of related biotic and abiotic factors on snail density. Methods: Four major vegetation communities: Sedge, Reed, Artificial poplar (3 years of age) and Artificial poplar (5 years of age), on the beaches of the Yangtze River in China were selected for vegetation and snail surveys, as well as for soil sampling. Structural Equation Model (SEM) analysis was used to assess the interactions of biotic and abiotic factors in the context of snail ecology. The soil properties were considered as abiotic factors, while algae of Chlorophyta, Cyanophyta and Bacillariophyta phyla were considered to be biotic factors. In the path analysis, the total effect between the variables was the sum of the direct and indirect effects. Results The snail density had significant correlations with soil properties, such as water content, bulk density, capillary porosity and pH value, as well as with all three types of soil algae, Chlorophyta, Cyanophyta, and Bacillariophyta. Snail density had a direct negative relationship with capillary porosity and soil bulk density, an indirect negative relationship with soil pH value and an indirect positive relationship with soil water content via soil algae. Meanwhile, as an important food source for the snail, the Chlorophyta, Cyanophyta and Bacillariophyta algae had a significant positive correlation with snail density. High soil pH had a negative impact on Chlorophyta, Bacillariophyta, while soil water content had a positive impact on Chlorophyta, and soil bulk density had a negative impact on Cyanophyta. In addition, the soil pH value and soil bulk density both had negative correlations with soil water content. Conclusion Afforestation of the beach environment can significantly reduce the snail population density by altering ecological factors. Soil algae (biological factors) might be the key element that drives ecological snail control. As important habitat determinants, the impact of the properties of the soil (non-biological factors) on the snail population was largely mediated through soil algae.