大山包黑颈鹤对旅游干扰的行为反应研究

利用警戒距离和惊飞距离两个指标来反映黑颈鹤对旅游干扰的耐受性。实验表明人数的不同对黑颈鹤的惊飞距离有所不同。研究还表明游客的干扰类型以喧哗为主,占总数的73.10%。噪音分贝对黑颈鹤的警戒距离有极显著影响(p=0.0000.05)。为了在提高游客旅游体验的同时,消除旅游活动对黑颈鹤的不利影响,建议最小接近区域面积=π×39.112=4802.92m2,该区域范围内限制游客进入,并在外围设立障碍物。     

不同扰动强度下城市重污染河道底泥对磷吸收和固定的影响

以重污染河道底泥和上覆水为材料,研究了周期性加入外源磷条件下,不同扰动强度下底泥吸附和固定磷的作用机制.结果表明,扰动可以增加底泥对外源磷的吸附,而且扰动强度越大,底泥对外源磷吸附效率越高.另外,尽管加入的磷以溶解性磷酸盐(DIP)形态存在,但扰动强化了DIP向颗粒态磷(PP)的转化,从而降低了水体中生物可利用磷含量.内源磷形态分析表明,弱吸附态磷(NH4Cl-P)呈降低趋势,而铁铝结合态磷(Fe/Al-P)、钙结合态磷(HCl-P)和残渣磷(Res-P)均呈增加趋势,但以Fe/Al-P增加幅度最大(占总磷的百分比超过80%,以3种扰动强度下平均值计).结合到非闭蓄态Fe/Al-P中的外源磷逐渐增加占Fe/Al-P净增加量的百分比分别为37.49%(100 r·min-1)、42.32%(200 r·min-1)、54.24%(300r·min-1),导致闭蓄态铁铝结合态磷净增加量占总磷净增加量的百分比随扰动强度增加有所降低,同样,钙结合态磷的变化趋势也基本一致.说明在较短的时间尺度上和较大的扰动强度下,连续加入的外源磷主要以易释放态磷形式存在,即底泥对外源磷的吸附以暂时性的持留为主.     

区域土地整理对生态系统的影响及补偿

为了降低土地整理对生态系统影响的负面效应,提出了生态补偿的经济措施、社会措施和生态措施.结合国家投资土地整理重点项目的规划设计,重点讨论了土地整理生态补偿的生态措施,主要通过农地平整工程设计、道路工程设计、农田灌排工程设计的生态学方法及生态边界设计等来实现.     

Recreational Portage Trails as Corridors Facilitating Non-Native Plant Invasions of the Boundary Waters Canoe Area Wilderness (U.S.A.)

Abstract:  Wilderness areas are protected and valued in part for recreation; recreational use, however, can negatively impact these areas. In particular, recreational use can facilitate transport of non-native propagules and create open sites for establishment of non-native species. We examined the role of recreational portage trails in the introduction and establishment of non-native plants into the Boundary Waters Canoe Area Wilderness of northern Minnesota (U.S.A.). On 20 portages, we sampled non-native plant richness and cover at four distances (0, 10, 25, and 50 m) from trails. Non-native richness and cover were not related to distance from wilderness entry point. Non-native richness and cover were, however, negatively related to distance from trails. All six non-native species we observed were either directly on or within 1 m of trails. These results suggest that recreational trails act as corridors facilitating invasions of non-native plants into wilderness areas. It remains unclear, however, whether these effects are caused by dispersal of propagules, creation of bare ground, or changes in the native plant community.     

日地环境对人类自发攻击性事件的影响

考察了日地空间物理环境扰动与人类自发攻击性群体性事件发生率之间相关性。统计分析发现，两者之间的相关程度很高，历元叠加后相关系数可达０．８４和０．７９、这表明日地空间物理环境对人类攻击性本能和情绪具有显著的调节作用，导致全球自发攻击性群体事件年发生率具有１１ａ准周期波动特征。其作用机制可能是地磁场活动和大气温度的影响。     

Loblolly pine response to wet-weather harvesting on wet flats after 5 years

The timing of forestry operations relative to weather conditions is a consideration in applying Forestry Best Management Practices (BMPs). Harvesting during different seasons can result in degrees of soil disturbance, the distribution of logging debris, and potentially future stand productivity. The purpose of this study is to examine the response of loblolly pine (Pinus taeda L.) stands after wet- and dry-weather harvesting combined with three site preparation treatments. A 20 × 20 meter grid was established in fifteen 20-year-old, 3.3-ha loblolly pine plantations in South Carolina. A census of soil physical disturbance and slash distribution was made after harvesting. Growth was measured on 1/125th-ha plots at ages two and five. Dry-weather harvested (DWH) sites were 91% undisturbed, and 9% compressed. Wet-weather harvested (WWH) sites were 41% undisturbed, and 59% disturbed. WWH sites averaged 9% bare soil, while DWH sites averaged 16% with 1 kg m^-2 less logging residue; primarily in the form of heavy and light slash. At age five, the green-weight biomass of flat-planted DWH and WWH sites were 13.3 and 12.6 kg tree^-1 respectively, and on the bedded DWH and WWH sites were 18.6 and 22.8 kg tree^-1. Wet weather harvesting did not seem to adversely affect stand growth, and may have improved it. Due to a prolonged drought, bedding had a larger effect on WWH sites than DWH harvested sites. The effects of droughty conditions may be influencing treatment response on these highly productive sites; however, the long-term effects of harvesting on stand growth remain to be seen.     

Aerial Monitoring of Marine Waterfowl in the Alaskan Beaufort Sea

The purpose of this study was to design and test a monitoring protocol for marine waterfowl in the central Alaskan Beaufort Sea. The study provides an important case-study of how a long-term monitoring program may be affected by unanticipated human disturbances.Because of its overwhelming and widespread abundance, relatively sedentary behavior, ease in counting, and the extensive historical database, the long-tailed duck (Clangula hyemalis) was selected as the focal species. Two null hypotheses were formulated concerning potential changes in the numbers and distribution of long-tailed ducks in relation to disturbance in an industrial study area, compared to a reference study area located about 50 km to the east.A 9-year historical database (1977–1984, 1989) of long-tailed duck densities and other important data recorded during systematic aerial surveys was analyzed retrospectively using multiple regression techniques. The retrospective analyses determined which of several predictor variables recorded were significantly related to long-tailed duck density. Separate analyses were conducted for two periods: (1) the overall period when long-tailed ducks were present in the lagoon study areas, and (2) the shorter adult male molt period. The results of the two analyses indicated that 57% and 68%, respectively, of the total variation in long-tailed duck density during the two periods could be explained by variables recorded during the surveys. Predictor variables representing habitat, day of the year, time of day, amount of ice, and wave height recorded on-transect during surveys were most closely associated with long-tailed duck density. Measurement error during the surveys, and influences outside the study area such as nesting success in tundra habitats and mortality during migration and in over-wintering areas likely also had strong influences on the results, but these factors were not measurable in our study.Based on results of the retrospective analyses, a long-term monitoring protocol consisting of a program of systematic aerial surveys and an analyses of variance and covariance (ANOVA and ANCOVA) statistical procedure was designed and initially tested in 1990 and 1991. This 2-year testing phase resulted in several revisions to the monitoring protocol. Refinements were made to the original sampling procedures, to the survey schedule, and to the recommended statistical analysis procedures. Results of the ANOVA and ANCOVA indicated that there was no evidence of a change in long-tailed duck densities that could be attributable to disturbance (from any source) in the industrial study area relative to a reference area with no industrial development. Other analyses indicated that the sampling and analysis procedures would be adequate to detect long-term trends in long-tailed duck density and localized disturbance effects, but that the monitoring program should be continued well beyond two years to detect statistically significant changes. As a result, additional aerial surveys of both study areas were conducted again during 1999–2001.Results of the revised ANOVA and ANCOVA of the 1990–1991 and 1999–2001 survey data indicated that the density of long-tailed ducks had significantly declined in coastal lagoons along the central Alaskan Beaufort Sea coast during the study period. In addition, disturbances throughout the barrier island-lagoon systems used by these ducks, including both the industrial and the reference study areas, had significantly increased over the same period. However, because unanticipated disturbances from a variety of anthropogenic sources, and not just industry sources, increased in both study areas, the reference study area was not an effective statistical control. As a result, the decline in long-tailed duck density in both study areas was not attributable to industry-related activities. Although the monitoring protocol described here is an effective method to detect statistically significant changes in long-tailed duck distribution and abundance in the nearshore Alaskan Beaufort Sea, many more years of sampling would be necessary to attribute observed changes to industry-related disturbances.     

含氯离子废水中化学需氧量的分析

对含氯离子废水化学需氧量测定技术进行了改进，提出了一种用硝酸银消除干扰的新方法。