Swarming of bats at underground sites in Britain—implications for conservation

We investigated the extent of visitation of underground sites during late summer and autumn (‘swarming’) by bats. Bats were captured at eight cave, mine and tunnel sites in southern England over 6 years (1995-2000). A total of 3077 bats representing 11 of Britain's 16 species was caught. Myotis bats predominated in autumn. At some sites these are rarely seen during winter hibernation counts. Myotis nattereri and M. daubentonii were most common. However, species composition changed seasonally. At one site, M. brandtii dominated early in the season and at all sites peak activity of M. daubentonii was earlier than in M. nattereri. Relatively high numbers of internationally vulnerable species such as M. bechsteinii and Barbastella barbastellus were recorded. There was a strong male bias in captures of swarming species. Swarming probably has an important reproductive function, most males are reproductively active at this time and such sites may be important for outbreeding. Due to this and the large number of individuals and species concerned, the conservation of ‘swarming sites’ is vitally important. Clearly swarming sites merit special consideration in conservation management strategies for cave-dwelling bats.     

双河洞小流域主要离子化学特征及其来源分析

为探究岩溶地表水和地下水水化学特征及其各种盐类对主要离子的贡献,以喀斯特小流域为研究尺度,对贵州绥阳双河洞区域地表水和地下水水化学进行野外监测、采样和室内实验,并运用SPSS统计软件对水样点进行主成分分析研究。结果表明:(1)双河洞水化学阳离子主要以Ca~(2+)、Mg~(2+)为主,阴离子以HCO_3~-和SO_4~(2-)为主。水化学类型主要为Ca~(2+)·Mg~(2+)—HCO_3~-型水,而石膏洞为Ca~(2+)·Mg~(2+)—SO_4~(2-)型水。大多数离子的含量随采样点、季节和水体类型的不同而呈显著性差异;(2)岩石风化对流域离子组成影响显著,阴离子主要来自碳酸盐、蒸发盐或岩盐的溶解和风化,蒸发盐溶解是阳离子的主要控制机制,硅酸盐风化侵蚀作用对区域离子变化存在一定影响;(3)主成分分析法得出对区域离子化学组成的影响程度按碳酸盐、蒸发盐和硅酸盐递减,其中H_2CO_3风化碳酸盐岩的影响显著,但在个别地下水主要受H_2SO_4风化碳酸盐岩的影响显著,此外农业活动和居民生活也有一定影响。研究结果对双河洞洞区水资源的保护和开发利用及岩溶碳循环研究具有重要意义。     

土壤CO2与喀斯特洞穴CO2季节变化响应分析

为了揭示土壤CO_2对洞穴内环境的意义,对大风洞和响水洞2016年洞内环境指标和上覆土壤的相关数据进行统计与回归分析。结果表明,洞内CO_2浓度、土壤CO_2浓度具有显著的季节性特征,土壤2#对应的洞内空气CO_2在夏冬两季差值达793~884mg/kg。土壤水PCO_2和滴水PCO_2在夏冬两季的差值最高可分别达1.12和0.41,因此洞内滴水PCO_2、土壤水PCO_2也表现出明显的季节性特征。土壤CO_2、洞内空气CO_2、洞内滴水PCO_2和土壤水PCO_2间均表现出一定的滞后现象,如4#土壤水PCO_2与滴水PCO_2的相关系数,由非滞后条件下的0.123上升至滞后条件下的0.596。同时在滞后条件下,土壤CO_2对洞内CO_2的贡献率的总和最高可达84.6%,高于非滞后条件下的值。     

重庆芙蓉洞洞穴滴水地球化学初探

2005年10月至次年4月的6个月内对重庆芙蓉洞滴水地球化学过程的监测发现：芙蓉洞2个观测点滴水均是矿化度很低的重碳酸盐水型,而地球化学过程受季节变化影响较大,人为影响相对较小;滴水中的pH、电导存在明显的季节变化;而2个观测点水化学组分的差异以及变化趋势的延迟,也可以初步判断出2个观测点可能由于水类型的不同而使其组分有所差异.     

Responses of three switchgrass (Panicum virgatum L.) cultivars to seed priming and differential aging conditions

Abstract

In switchgrass (Panicum virgatum L.) cultivation, rapid and uniform germination is essential because it is one of the most promising candidates for biofuel production. Priming, a seed enhancement technique with solid carriers, can be a useful tool for improving germination characteristics of switchgrass seeds. The objective of this study was to determine the effectiveness of priming on three non-aged and aged switchgrass cultivars of ‘Cave in rock’ ‘Dacotah’, and ‘Kanlow’. Seeds were primed with a synthetic calcium silicate (MicroCel E) and water at 30°C for five days. Seed, carrier and water proportions were 1 g, 0.5 g, and 1.5 mL, respectively. There was a 5% point (pp, Cave in rock), 8 pp (Dacotah), and 19 pp (Kanlow) increase in primed seeds compared with non-treated control seeds. Furthermore, priming decreased mean germination time by 26–36% in all seeds compared with the non-treated control. Accelerated aging was induced by storing seeds for 0, 10, and 21 days at 42°C and 95% relative humidity (RH). Germination percentage decreased and mean germination time increased with the aging. These results suggest that priming is an effective technique to improve the performance of switchgrass cultivars.     

福建永安桃源洞种子植物区系地理成分分析

永安桃源洞风景区内种子植物129科423属757种,隶属10个科分布区类型和14个属分布区类型。具有地理成分复杂,热带成分明显,温带成分较多,起源古老和特有成分丰富等特点。     

旅游活动对洞穴生态环境的影响分析

通过查阅有关文献资料,并结合所监测的重庆雪玉洞洞穴生态环境,分析认为:旅游活动使得洞穴CO2含量呈升高趋势,洞穴温度也呈升高趋势且变幅增大,洞穴空气湿度呈降低趋势,还可能破坏洞穴生态系统,这对洞穴碳酸盐岩沉积物的保护十分不利,应引起人们足够的重视。此外,旅游活动很容易恶化地下河水的水质,威胁岩溶区的饮水安全。     

元帅系苹果产地贮藏系列技术

本项系列技术既能保持果实新鲜状态,又能节约能源。主要是成功地改进了原有的贮藏场所,充分地利用了自然冷源,使建库投资比冷库（商业用0℃库）减少2/3以上,节约电能4/5以上。采用PVC袋包装,由果实自身呼吸减少贮藏环境内的O#-2浓度和提高CO#-2浓度。在贮藏初期库温控制在15-10℃时,CO#-2控制在10-15%,O#-2不低于2%。随着库温逐渐下降,CO#-2和O#-2浓度分别下降和上升到10%左右。贮藏元帅系苹果6个月,果肉硬度可保持在12Ib/cm#+2以上,损耗率为2-5%。总结提出了高温、高CO#-2、高O#-2和高C#-（2）H#-4贮藏技术,除少数对CO#-2敏感的品种之外,其它苹果亦可应用。     

喀斯特洞穴滴水水文化学过程的时空变化及其环境指示——以贵州织金洞为例

洞穴水地球化学过程的研究对于洞穴内次生沉积物景观的发育有着重要的意义,2015年1—12月通过现场滴定测量和实验室仪器分析对贵州织金洞洞穴水的水化学指标进行了为期一个完整水文年的动态监测,采样时间均为每月26—28日。结果表明:(1)洞穴滴水滴率和Ca~(2+),Mg~(2+),Sr~(2+)离子浓度均与降水量有很好的响应,但同时都表现出一定的滞后性,其中Mg~(2+),Sr~(2+)离子所携带的气候信号较为持久,Ca~(2+)离子浓度在雨季波动较大。(2)滴水水化学性质在化学计量上总体符合石灰岩喀斯特地区的侵蚀方程,Ca~(2+)/HCO_3~-的比值均在1/2上下波动;(3)滴水中的SIc和SId之间存在显著的正相关关系,滴水中的液相CO_2分压[lgPCO_2(water)]与pH值之间呈现出显著的负相关,体现了上覆土壤层中的高浓度CO_2对洞穴滴水化学过程的重要影响。(4)滴水中的Mg/Ca与Sr/Ca比值在雨季到来后的曲线变化呈现出明显的同增同减性特征,证明CaCO_3在未到达洞穴之前就已经在土壤层和基岩层中发生了优先沉积(PCP),致使运移到洞内的Ca~(2+)离子浓度相对其他离子的升高程度小;(5)滴水中Mg/Ca比值与Sr/Ca比值都有较明显的季节变化,但是Sr/Ca比值季节滞后性明显,而Mg/Ca比值年际变化更具波动性,对外界降水变化响应较敏感。     

贵州冷热洞、白龙洞和龙井洞环境质量及生态风险初步评价

为了解贵州喀斯特洞穴环境的污染状况,对贵州省3个洞穴冷热洞、白龙洞和龙井洞部分环境因子——土壤和水中重金属(Cu、Cr、Ni、Zn、Hg和As)含量进行测定,并对3洞穴土壤中重金属的污染指数及生态风险进行评价。结果表明:Zn在土样和水样中含量均最高,最低的是Hg;冷热洞土样的重金属含量均超过中国土壤背景值,白龙洞和龙井洞土样中的重金属含量除Cr外,均超过中国土壤背景值。洞穴土壤重金属综合潜在危害程度,龙井洞处于较高生态危害水平,冷热洞处于中等生态危害水平,白龙洞处于高生态危害水平;Hg是3洞穴最主要的生态风险因子。