北洛河流域植被恢复的支撑体系

北洛河流域自实行退耕还林政策以来取得了显著成效,但是实践证明植被恢复不是简单的种树种草,必须要根据生态学原则合理种植,既要有技术支撑,还必须考虑到退耕后农民的生存问题,也就是粮食与能源的问题,并要保证农民有一定的经济收入,最后指出要解决好以上问题,必须靠国家政策的支撑。     

广西主要树种冰雪灾害调查及恢复措施

通过对广西冰雪灾区森林受害情况进行实地调查,对树种、坡向、海拔高度等因子与林木受灾的关系进行了探讨。调查结果表明:广西主要树种抗灾害能力的大小为油茶>八角>杉木>松树>桉树>毛竹,乡土树种>外来树种;海拔对树种灾害的影响呈S型曲线,随海拔高度的升高而加重;坡向、林木种植模式和经营方式对林木灾害的影响为阴坡>阳坡,纯林>混交林,采脂的松树>未采脂的松树。因此,提出了以下建议:(1)选择抗寒抗逆性树种品种;(2)多发展乡土树种;(3)大力发展混交林;(4)合理布局,科学管理;(5)针对受灾情况,采取不同的恢复技术措施等。     

冬季喷施多效唑对荔枝叶片叶绿素荧光特征的影响

为弄清多效唑(PP333)对荔枝叶片光合能力的影响,于2011年12月对‘妃子笑,荔枝整株喷施PP333(500 mg/L),研究其对叶片叶绿素指数和叶绿素荧光动力学参数的影响.结果表明:喷施PP333可显著增加荔枝叶片的SPAD值,且使Fv/Fm、Fv/F0、Fv′/Fm′、ΦPSⅡ、ETR、PCR等叶绿素荧光参数有所增加,而NPQ则降低;从光响应曲线可以看出,Fv′/Fm′、ΦPSⅡ和qP随光化光强度的增加呈下降趋势,而NPQ、PCR和ETR随光化光强度增加而增加;从PSⅡ反应中心能量分配比率上看,PP333处理后P、E增加,D减小,更有利于能量进入PSⅡ反应中心,促进光化学效率提高;PP333处理可以增加PSⅡ反应中心的开放比例,推动光合电子传递,提高荔枝叶片的光合性能.     

Dung decomposition and pedoturbation in a seasonally dry tropical pasture

Rates of dung decomposition and the associated accumulation of soil transported to the surface were compared for dung deposited during a dry and a wet season in a Costa Rican pasture. Average decomposition rates for the first 140 days after deposition were significantly lower for dung patches deposited at the beginning of the dry season than for patches deposited at the beginning of the wet season (0.73 vs. 1.50 g/day^-1 on a dry weight basis). A strong linear relationship was found between dung removal and soil accumulation at the original soil surface, with an average of 2.0 g soil accumulated for every gram of dung which was removed. This relationship was not affected by deposition season. The lack of a seasonal difference, along with the relatively low decomposition rates during the wet season, were explained by the dominance of termites in the dung patches throughout the year. Evidence of dung beetle activity was never recorded during the dry season and was found in only 18 of the 45 dung patches recovered during the wet season.     

竹类植物在黄河三角洲盐碱地生态修复中的应用进展

黄河三角洲地区受地势低平、海水易内侵、蒸发量大于降雨量等因素影响,形成了大量盐碱地,对该地区盐碱地进行生态修复具有重要的生态安全意义。文章综述了黄河三角洲盐碱地成因、盐分主要构成、盐胁迫对植物尤其竹类植物的影响,以及竹类植物在滨海盐碱地应用种植情况,认为竹类植物具有很好的观赏性和生态及经济价值,在滨海盐碱地有种植先例和研究报告,种植技术成熟,可以通过筛选、引种、驯化耐盐碱竹类植物,在黄河三角洲盐碱地生态修复中应用。     

光照强度对烤烟化学成分及物理特性的影响

对不同光照强度下烤后烟的矿质元素、主要化学成分、物理特性进行了分析。结果表明:氮、钾、钙、氯、铜、淀粉、还原糖含量,钾/氯,单叶重,叶质重,叶片厚度受光照强度影响较大;铁、锌、总糖含量,含梗率受光照强度影响次之;而磷、镁、平衡含水率受光照强度影响不显著;≥80%全光照适合优质烟叶的生产。     

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 ...     

浅谈围填海历史遗留问题的生态修复措施——以增殖放流为例

增殖放流是围填海历史遗留问题的生态修复措施之一,能直接弥补项目建设造成的海洋生物资源损失,目前应用广泛。文章结合浙江省宁波市和舟山市的实际放流工作经验,从实施主体、放流品种、放流地点和放流效果等方面进行探讨,提出和分析所遇到的问题,并给出相应的对策和建议,可为后续增殖放流工作提供参考。     

4种苔藓植物在喀斯特石漠化地区的生态修复意义

为探求苔藓植物在石漠化地区的生态修复意义,筛选出4种石漠化地区常见的苔藓,即美灰藓(Eurohypnum leptothallum)、小青藓(Brachythecium perminusculum)、双色真藓(Bryum dichotomum)和多疣细羽藓(Cyrto-hypnum pygmaeum),测定其生物量、饱和吸水率、根系密度、蒸腾速率和抗冲刷能力,并初次将该4种苔藓应用于石漠化修复的实践中,对其土壤酶活性进行了1年的跟踪监测。结果表明:(1)4种苔藓持水保水能力差异显著,其生物量由大到小依次为美灰藓双色真藓小青藓多疣细羽藓;饱和吸水率最低的是多疣细羽藓(660.78±3.46)%,最高的是美灰藓(1 627.82±4.68)%。(2)双色真藓的蒸发速率最高可达6.63g/(kg·h),其水分更容易丧失;美灰藓蒸发速率为0.93g/(kg·h),水分较其他苔藓不易丧失。(3)4种苔藓的抗冲刷能力与其假根的根长密度、根重密度、生物量存在显著正相关关系,美灰藓在各组冲刷试验中表现出较强的抗冲刷性,可以有效减少土壤流失。(4)4种苔藓均可有效提高被培养土壤的酶活性。苔藓层生物量、抗冲刷强化值、假根根系密度与土壤脱氢酶、脲酶呈正相关关系。4种苔藓均具有较高的水土保持效益,其中美灰藓的表现更为显著,建议利用物种演替规律将苔藓应用于石漠化修复的实践中。     

Research needs for restoring seasonal tropical forests in Thailand: accelerated natural regeneration

Accelerated natural regeneration (ANR) is a relatively cheap method of reforestation, which encourages natural establishment of indigenous trees and shrubs. It requires a low input of labour, but a high input of ecological information. In this paper, the knowledge required to predict and manipulate the natural regeneration of seasonal tropical forest is reviewed and areas in need of further research are identified. Regeneration will be influenced by five groups of potentially limiting factors; site resources (soil and microclimate); competition with weeds; site disturbance; occurrence of established woody plants or their propagules; seed dispersal by wild animals and birds. This paper considers each of these, their interactions with seasons, and each other. Collation of existing information on these topics, combined with the suggested further research, should facilitate the creation of tools that will enable practitioners to judge the regeneration potential of sites and to select the most appropriate ANR techniques.