Enclosure culture ban and its effects on water quality and phytoplankton community in a subtropical shallow lake

Enclosure culture, ubiquitous anthropogenic activity in shallow lakes, was prohibited in East Taihu Lake with all breeding infrastructure demolished at the end of 2018. However, the ecological responses of water quality change and phytoplankton community succession to the enclosure culture ban remain largely unknown. In this study, we conducted field investigations monthly in East Taihu Lake to present a comprehensive study of water quality and phytoplankton community variation before (2018) and after (2019) the enclosure culture ban. With the cessation of aquaculture activities, water quality significantly improved, TN and TP decreased by 54% and 34%, respectively, and eutrophic state shifted from light eutrophic (mean TSI = 59) to mesotrophic status (mean TSI = 48) in autumn. Chl-a decreased from 33.34 ± 16.87 to 24.84 ± 15.43 μg/L, and SDD increased from 0.76 ± 0.19 to 0.95 ± 0.36 m. Meanwhile, phytoplankton abundance significantly decreased from 3.6 × 10⁷ to 1.6 × 10⁷ cell/L, with the contribution of Cyanophyta markedly decreasing from 82% to 63%. In addition, the heterogeneity of phytoplankton community markedly increased. The changes in water quality and phytoplankton following the enclosure culture ban were largely due to the suspension of external nutrient input from breeding activity and improved water clarity. Redundancy analysis (RDA) analysis further elucidated that water temperature and nutrients were the main factors affecting phytoplankton dynamics. Our findings showed that the ban on enclosure culture had an extremely positive ecological impact.     

云南香蕉病虫害危害现状及防治策略

通过调查研究,报道云南香蕉病虫害种类、危害现状和当前病虫防治工作中存在问题,提出防治策略和建议。     

云南4个烤烟品种烟叶主要化学成分含量的变异分析

对云南省55个县种植的4个主栽烤烟品种烟株烟叶的主要化学成分含量的变异进行了分析。结果表明:不同烤烟品种的烟株烟叶主要化学成分含量在不同品种间除氯的含量和钾氯比外,其他指标在各品种间均存在极显著或显著差异。聚类分析可将云南主栽的此4个烤烟品种划分为两大类,第I类为红花大金元,第II类群为K326、云烟85和云烟87。依据烟叶化学成分含量除红花大金元外,对云南的3个烤烟主栽品种的种植区域进行了划分。云烟85在云南的55个种植县可分成10个类群;K326在云南的49个种植县可分成19个类群;云烟87在云南的23个种植县可分成9个类群。     

华东监测区森林资源监测体系现状及其完善对策

论述与分析了华东监测区森林资源监测体系的现状,侧重于论述目前森林资源规划设计调查的状况和存在的种种问题.在此基础上,为了能使地方森林资源监测体系更好地服务于现代林业建设,在调查区划、质量控制等方面提出了改进森林资源规划设计调查的措施,同时也提出了注重土地属性调查、加大经费投入等对策来进一步完善地方森林资源监测体系.     

东江源区水环境管理体制创新研究

指出了东江源区水质的好坏直接影响东江中下游水质,有效管理东江源区水环境是关系到江西省、广东省和香港人民饮水安全的重要工作。分析了东江源区水环境管理中存在的问题,针对创新有效的东江源区水环境管理机制进行了探讨。     

林改后实现山区林农稳定增收的途径分析

集体林权制度改革后,将林地使用权、林木所有权和使用权落实到农户,确定了林农在林业经营中的主体地位,林农的爱林护林积极性将得到极大提高;另一方面,林农的经济利益和林区的生态建设之间短期内会出现矛盾,那么如何做到既鼓励林农种树护林的积极性并促进其增收,又维护生态和谐,这是必须解决的问题。本文结合云南省林权制度改革的实际情况,对上述问题进行了阐述。     

云南省荔枝树根际的两种拟鞘线虫

描述了采自云南省果树根际的隶属于环科[Criconematidae(Taylor,1936)Thorn,1949]、环亚科(Criconematinae Taylor,1936)的两种线虫荔枝拟鞘线虫(Hemicriconemoides litichi Edward & Misra,1963)和紧鞘拟鞘线虫(Hemicriconemoides stricta the catus     

Genetic identity of the Bemisia tabaci species complex and association with high cotton leaf curl disease (CLCuD) incidence in Pakistan

BACKGROUND: The cotton whitefly, Bemisia tabaci (Gennadius), is a cryptic species complex, and members of the complex have become serious pests in Pakistan because of their feeding and their ability to transmit cotton leaf curl virus (CLCuV). Here, an analysis was made of the identity of B. tabaci collected from cotton and a range of non‐cotton hosts in the cotton‐growing zones in Punjab and Sindh, the main cotton‐producing provinces of Pakistan, using a portion of the mitochondrial cytochrome oxidase 1 gene. The geographic distribution of the different members of the complex was then compared with the incidence of CLCuD. RESULTS: Using the Dinsdale nomenclature, the results revealed three putative species, Asia 1, Asia II 1 and Middle East‐Asia Minor 1. Asia II 1 (also referred to in the literature as biotypes K, P, PCG‐1, PK1, SY and ZHJ2) was only recorded from Punjab cotton plants, whereas Asia 1 (also referred to in the literature as biotypes H, M, NA and PCG‐2) was found in both Sindh and Punjab. Middle East‐Asia Minor 1 (commonly known as biotype B and B2) was found only in Sindh. Moreover, Asia II 1 was associated with high incidences of CLCuD, whereas regions where Middle East‐Asia Minor 1 was present had a lower incidence. Phylogenetic analysis showed that the Middle East‐Asia Minor 1 population in Sindh formed a distinct genetic subgroup within the putative species, suggesting that the Sindh province of Pakistan may form part of its home range. So far, no individuals from the putative species Mediterranean (commonly known as biotypes Q, J and L) have been found in Pakistan. CONCLUSIONS: The capacity to manage pests and disease effectively relies on knowledge of the identity of the agents causing the damage. In the case of CLCuD in Pakistan, this knowledge has been obscured to some extent because of the inconsistent approach to identifying and distinguishing the different B. tabaci associated with CLCuD. The situation has now been clarified, and a strong association between disease incidence and vector identity and abundance has been shown. Given this advance, future research can now focus on factors that influence the capacity of different vector species to transmit the viruses that cause CLCuD, the reason for differences in vector abundance and the lack of geographic overlap between the cryptic vector species. This knowledge will contribute to the development of improved methods with which to manage the disease in Pakistan. Copyright © 2010 Society of Chemical Industry     

丽江云杉大痣小蜂的潜在分布区预测

根据丽江云杉大痣小蜂在云南的分布点数据和环境数据,通过Maxent模型预测了丽江云杉大痣小蜂在云南的潜在分布区域：高适生区主要包括丽江市的永胜县,玉龙县,华平县,宁蒗县;中适生区包括迪庆州的雏西县、大理州北部、楚雄的大姚县、永仁县、元谋县、昆明的东川区;低适生区包括昆明市,怒江州西部,保山市,临沧市北部,普洱市的景东县,曲靖市的大部分地区,红河州的大部分地区;除上述地区外其余地区为丽江云杉大痣小蜂的非适生区。该研究的训练数据和测试数据的AUC值分别为0．995和1．000,表明Maxent模型对该蜂在云南的潜在分布区预测有显著的统计学意义。     

云南省野生食用菌气候生境特征与评价

云南省地处低纬,属高原山区。受地理和季风气候的共同影响,境内光热资源丰富、气候立体、干湿分明、雨热同季,为野生食用菌生长提供了优质的气候生境。为揭示云南省野生食用菌气候生境特征及其与全国部分野生食用菌产地间的气候生境差异,选取了云南省125个县及全国部分野生食用菌产地(5—10月)的气温、地温、降水、日照、湿度和海拔高度,进行多因子影响的主成分分析、干燥度计算和单个气象因子分析,最后在arcgis平台上做IDW插值。结果得出:云南省野生食用菌菌丝体向子实体过渡初期光、热量充足,干湿转换明显,子实体收获期长,收获盛期热量和降水适中,且变幅小,昼夜温差大。晴雨交错的野生食用菌气候生境特征惟云南独有,并可大致划分为滇中以北高海拔冷凉气候生境区、滇中及周边中海拔温暖气候大宗菌类生境区和滇南温热气候生境区;其中滇中楚雄州为中心向东西延伸的同纬度、同海拔地带的5月、6月、7—9月的平均气温为20℃、21℃、20℃,降水量为80 mm、150 mm、480 mm,相对湿度为67%、77%、83%,日照时数为220 h、160 h、380 h,与野生食用菌最适宜气温、降水和空气湿度条件一致,是云南省野生食用菌大宗品种丰富区和产量最高区。