元谋干热河谷山地植被修复区土壤种子库研究

 为了解干热河谷不同植被修复方法的土壤种子库的变化模式,采用对不同处理地段(包括水平阶间坡面、自然坡面、沟底)和对照(放牧地)的土壤种子库组成、大小进行比较研究的方法,研究元谋干热河谷山地植被修复区的土壤种子库。结果表明:1)植被修复区土壤种子库密度、丰富度均大于对照区;2)修复区内第2年土壤种子库密度、丰富度均大于第1年;3)水平阶间坡面和各类型间的土壤种子库密度差异显著;4)种子库中草本植物占很大比例;5)孔颖草和扭黄茅是种子库2大优势种。研究项目所采取植被修复措施在很大程度上改善土壤种子库的数量结构和物种组成。     

婺源黄喉噪鹛繁殖生境研究

黄喉噪鹛华南亚种(Garrulax galbanus courtoisi)自2000年5月在婺源被重新发现以来,受到国际鸟类保护组织的关注。自2004年起,笔者对其4个繁殖地开展了生境调查,并对其繁殖期的活动范围、巢区、夜宿地、觅食地进行了比较分析。结果表明:作为适应天然常绿阔叶林的特化物种,其独特习性显现出对天然常绿阔叶林的适应。建议从保护好婺源的天然常绿阔叶林入手,同时加强自然保护小区管理,以更好地保护黄喉噪鹛的生境。     

纳板河自然保护区景观连接度变化分析

自然保护区是保护物种栖息地的重要基础,但频繁的人类活动干扰导致自然保护区内生物栖息地斑块破碎化的问题依然存在,景观连接度定量评价对于保护区生物栖息地保护具有重要作用。以纳板河自然保护区为例,基于图论的指数方法利用2014年和2018年高空间分辨率遥感数据,对保护区栖息地的景观连接度指数的变化及其驱动力因素进行分析。结果表明:1)2014—2018年的景观连接度指数中整体性连接度指数(IIC)、概率连接度指数(PC)都呈现下降趋势,IIC和PC指数分别下降0.29和0.53,指示保护区内栖息地破碎化加剧;2)最大斑块的重要性指数从85.14减少到84.19,重要性前十的斑块时空变化表明了自然保护区栖息地斑块面积不断减小,中部、中西部地区破碎化显著;3)土地利用变化对保护区景观连接度产生重要影响,其中橡胶林、耕地、水库、茶园4类土地利用增加是栖息地破碎化的驱动力因素。研究结果可为纳板河自然保护区栖息地保护管理提供科学依据。     

木麻黄基干林带修复改造中优良品系的选择

海岸风口基干林带修复除木麻黄(Casuarina equisetifolia)外尚无可替代树种,选择抗性优良的木麻黄品系是基干林带修复的关键环节.通过对"惠-1"木麻黄、圆头木麻黄、千头木麻黄、铺地木麻黄等4个品系进行造林和抗风试验,比较几个品系在风口最前沿、近风口的生长和抗风表现,结果表明:风口基干林带修复采用"惠 ...     

河南省国家湿地公园建设管理措施与成效分析

国家级湿地公园机制运行具有有效整合“脆弱”湿地,提高湿地及其周围环境的自然生产力, 保障湿地公园规范运行,管理有效,进行湿地红线管理,牢牢守护生态红线的优势。以伊川县伊河国家湿地公园为典型案例,从“黄河流域生态保护和高质量发展”的国家战略、湿地生态系统、科普宣教、经济社会等角度分析了河南省国家级湿地公园建设的举措、管理方法以及取得的成效,为湿地公园建设提供借鉴。     

木芙蓉上亚利桑那跳小蜂对扶桑绵粉蚧的寄生研究

扶桑绵粉蚧Phenacoccus solenopsis Tinsley是我国重要观赏和药用植物木芙蓉上的主要害虫之一,但迄今对其被优势天敌亚利桑那跳小蜂Aenasius arizonensis (Girault)（班氏跳小蜂A. bambawalei Hayat）的寄生情况了解甚少。为此,自2017年开始,在浙江兰溪西部的一个木芙蓉种植区开展了为期四年的调查,每年6—9月,分批从木芙蓉植株上采集3龄若虫及未产卵雌成虫,于室内观察寄生情况;并于其中两年观察了不同生境中的寄生情况,探讨了寄生季节变化的动态特征及相关影响因素、杂草促进寄生的途径以及增强该粉蚧自然控制的措施。结果表明,在前期（6—7月）寄生率总体上较低,其中两年最高分别仅有38%和32%,另外两年也很少发现被寄生个体,而且该时期寄生率年份间存在明显波动。而在后期（8—9月）,寄生率相对较高,且具有从8月上旬开始逐步上升这一显著特点。观察期间,最高寄生率均出现于各年份9月下旬,四年中分别为89%、62%、55%和13%,年份间差异十分明显。生境类型可对寄生水平产生较大影响,与木芙蓉地块内和杂草稀疏的田埂相比,杂草丛生的田埂上和路...     

鱼类栖息地保护技术研究进展

为进一步促进鱼类栖息地保护与修复工作的深入开展以及保护技术的推广应用,综述了国内外鱼类栖息地评估方法和保护与修复技术的发展概况,归纳了常用的鱼类栖息地评估方法,总结了鱼类栖息地保护与修复项目中运用的技术,分析了现有保护措施存在的问题,提出了较全面的鱼类栖息地评估方法和修复措施的建议,以期为从事鱼类栖息地保护与修复工作的技术人员提供技术参考。     

Long-term consequences of topsoil mining on select biological and physical characteristics of two New Zealand loessial soils under grazed pasture

Soil chemical, biochemical, biological and structural properties were measured in two New Zealand loessial soils that were topsoil-mined 10 and 25 years ago respectively. Measurements at the 10-year site were compared to some earlier measurements made at this site and the data combined in a chronological sequence for analysis. Topsoil mining had a large, detrimental impact on the soil microbial biomass, the earthworm populations, easily mineralizable N and soil enzyme activities. However, most of these properties substantially recovered, to 80-90 per cent of the levels in unmined soils, within 10-25 years of restoration under pasture. In contrast, while total soil C and N were less affected by topsoil mining, their recovery was much slower. Stabilities of macro-aggregates of soil had fully recovered within 10-25 years after topsoil mining. The apparent changes in all the measured properties between 10 and 25 years of restoration were small in comparison with changes between 0-10 years of restoration after topsoil mining. The total C content of both soils under pasture appeared unlikely to attain the levels present in unmined soils. In soils undergoing restoration, the ratio of microbial C/total soil C may be a useful index of soil ‘biological stability’. Sulphatase activity may reflect the recovery of pasture production.     

粤北地区 3 种生境红火蚁蚁丘分布及影响因素

【目的】研究红火蚁在粤北地区不同生境中红火蚁蚁丘的分布特征,为该虫的监测、防治提供科学依据。【方法】采用样方方法调查3种生境(荒地、田埂、草坪)红火蚁蚁丘的密度和大小,采用聚集度指标法和Taylor幂函数回归模型对蚁丘的空间分布型进行研究,并对荒地生境蚁丘密度和植物多样性进行相关性分析。【结果】田埂蚁丘密度明显高于荒地和草坪,高达18.67个/100 m~2,超过草坪生境蚁丘密度的10倍;荒地、田埂和草坪生境蚁丘基部周长相差不明显,但荒地生境蚁巢高度明显高于田埂和草坪;通过聚集度指标和Taylor幂函数来看,荒地和田埂生境蚁丘多表现为均匀分布或随机分布,而草坪生境蚁丘多表现为聚集分布;研究发现粤北地区红火蚁入侵并未造成荒地生境植物多样性下降。【结论】受人为干扰等因素影响,红火蚁在粤北地区不同生境发生程度由重到轻依次为田埂、荒地、草坪;蚁丘在荒地和田埂上多呈均匀分布或随机分布,在草坪上多呈聚集分布,这种分布差异主要是由人为干扰和红火蚁筑巢习性共同引起的;红火蚁蚁丘密度与荒地中植物多样性呈正相关趋势,但相关性不显著。     

Responses of plant community to the linkages in plant-soil C:N:P stoichiometry during secondary succession of abandoned farmlands,China

Succession is one of the central themes of ecology;however,the relationship between aboveground plant communities and underground soils during secondary succession remains unclear.In this study,we investigated the composition of plant community,plant-soil C:N:P stoichiometry and their relationships during secondary succession after the abandonment of farmlands for 0,10,20,30,40 and 50 a in China,2016.Results showed that the composition of plant communities was most diverse in the farmlands after secondary succession for 20 and 50 a.Soil organic carbon and total nitrogen contents slightly decreased after secondary succession for 30 a,but both were significantly higher than those of control farmland(31.21%-139.10%and 24.24%-121.21%,respectively).Moreover,C:N ratios of soil and microbe greatly contributed to the changes in plant community composition during secondary succession of abandoned farmlands,explaining 35.70%of the total variation.Particularly,soil C:N ratio was significantly and positively related with the Shannon-Wiener index.This study provides the evidence of synchronous evolution between plant community and soil during secondary succession and C:N ratio is an important linkage between them.