Moreton Bay, Queensland, Australia: an example of the co-existence of significant marine mammal populations and large-scale coastal development

Recent analyses assert that large marine vertebrates such as marine mammals are now ‘functionally or entirely extinct in most coastal ecosystems’. Moreton Bay is a large diverse marine ecosystem bordering the fastest growing area in Australia. The human population is over 1.6 million and increasing yearly by between 10% and 13% with resultant impacts upon the adjoining marine environment. Nonetheless, significant populations of three species of marine mammals are resident within Moreton Bay and a further 14 species are seasonal or occasional visitors. This paper reviews the current and historical distributions and abundance of these species in the context of the current management regime and suggests initiatives to increase the resilience of marine mammal populations to the changes wrought by the burgeoning human population in coastal environments.     

Waterfowl-habitat associations during winter in an urban North Atlantic estuary

Coastal habitats near urban centres in North Atlantic estuaries often support substantial numbers of wintering waterfowl, but little is known of the effects of landscape setting and urbanisation on habitat use. We conducted surveys of waterfowl at 32 wintering sites in Narragansett Bay, Rhode Island, to identify characteristics that may influence habitat use. Sites were chosen along a gradient of urbanisation and reflected the dominant habitat types used by waterfowl in the Bay. Mean waterfowl abundance was 206.7 ± 209.5 birds per site, and sites in the inner part of the estuary had higher overall waterfowl abundances (r² = 0.40, p = 0.021). Species richness ranged from 3.2 to 13.0 and decreased with increasing hunting activity (r² = 0.36, p = 0.040). Hunting activity and habitat characteristics (e.g., latitude, shoreline configuration, prey density) explained 13-27% of the variation in waterfowl abundance and species richness among sites, but landscape characteristics (e.g., surrounding residential development, vegetated land, or wetland surrounding the sites and the extent of wetland edge) explained an additional 1-26%. The landscape characteristics extent of adjacent residential development and vegetated upland were the most common variables entering into the models; most species were more abundant at sites with more adjacent vegetated upland and less adjacent residential development. Our results suggest that landscape setting may be influencing the distribution of wintering waterfowl, and should be considered when developing strategies for the conservation for these species in urban North Atlantic estuaries.     

Human-driven impacts on marine habitats: A regional meta-analysis in the Mediterranean Sea

Habitat destruction is one of the main threats to environmental integrity. Assessing the consequences of human impacts is crucial both to predict and prevent structural and functional changes of habitats. However, to date almost all studies on marine threats, from regional to global scales, have been entirely qualitative and generally based on little more than expert opinion. We have developed a meta-analytical approach to quantify overall effects of various stressors on different Mediterranean habitat types and to compare the relative importance of different impacts across a range of habitats. We first qualitatively reviewed and synthesized 366 experiments (either manipulative or correlative) collected in the literature. After a selection procedure, we finally quantitatively meta-analyzed 158 experiments. We showed that fisheries (destructive or not), species invasion, aquaculture, sedimentation increase, water degradation and urbanization have negative effects on Mediterranean habitats and associated species assemblages. We also explored the overlap between the impacts identified as important in the Mediterranean and those identified by experts as being important globally, highlighting the inadequacies of relying on expert opinion alone. Finally, we drew attention to the critical lack of empirical knowledge about marine systems in many areas of the Mediterranean, which impedes the implementation of effective conservation measures. Our study is the first to synthesize experimental analyses on human-driven impacts on marine habitats across such a broad geographic scale.     

Lakeshore diversity and rarity relationships along interacting disturbance gradients: catchment area, wave action and depth

Diversity patterns of riparian plant communities have been associated with disturbance. Populations of a diversity of Atlantic Coastal Plain plants occur as disjuncts on shores of large catchment area lakes in Nova Scotia. These lakeshore communities contain rare plants with local, national and global rankings. The populations of rare plants are dynamic and their management requires an understanding of the relationship between disturbance and the survival of rare plants. This present study measured (overwinter wooden dowel removal) and observed disturbance along gradients of catchment area (CA), exposure and depth. In three separate experiments ranging from the landscape to the lake, to the single shoreline level, disturbance was linked to lake CA, exposure and depth, respectively. At all scales, disturbance was positively associated with the presence of rare species. The pattern of rare species richness over the river system was complex; at the within-lake level, the frequency of rare species per site was greatest in the intermediate CA lake while the pool of rare species was greatest in the largest CA lake. The findings focus field efforts on wide, exposed shorelines of large CA lakes where new rare plants continue to be discovered. In addition, the discrepancy between highest frequency of rare plants on intermediate CA lakes and highest species pools of rarities on large CA lakes, reinforces the need for larger protected area systems for the most naturally disturbed ecosystems which often support populations having a high turnover rate but a low site to site frequency.     

Assessment of shoreline vegetation in relation to use by molting black brant Branta bernicla nigricans on the Alaska coastal plain

To evaluate the importance of large thaw lakes on the Alaska Coastal Plain for molting Pacific black brant Branta bernicla nigricans, distribution and life form of shoreline vegetation were assessed using several scales: satellite imagery, point-intercept transects, cover quadrats, and a parameter for water regime. Brant population and distribution estimates from aerial surveys were used to classify large lakes into high, moderate, and low use. Correlations between brant and abundance of their preferred feeding site — moss flats — were best demostrated by satellite imagery. Intercepts and cover ratings were not correlated, presumably because these techniques were less efficient at assessing area. General observations suggested that the presence of islands, large ice floes, and possibly other physical attributes of the habitat, influenced brant distribution. This area is unique because of low-lying, drained-lake basins that have ideal combinations of moss flats and large water areas where brant seek protection disturbance is vital to the success of this declining species because alternate habitats may not be available elsewhere on the Coastal Plain. in water or on ice floes. Protection of the area from     

Effect of effective microorganism and gypsum amendments on nutrient leaching,pH, electrical conductivity,and Okra growth parameters under coastal saline soil

Nutrients losses through leaching are the main problem facing coastal saline soil. Effective microorganisms (EM) and Gypsum (G) at the application rate of 5%G and 10%G by weight were used as soil amendments. The pot experiment aimed to improve the leaching of nitrate (NO₃), ammonium (NH₄) and total nitrogen (TN) on the coastal saline soil. The EM+ 5%G treatment effectively reduced the content of NO₃ and NH₄ in the leachate by 86.59% and 68.18%, respectively. EM treatment reduced the leaching of NO₃ and NH₄ by 70.86% and 62.12% and EM+ 10%G reduced NO₃ and NH₄ by 11.80% and 50.76%, respectively. Moreover, the content of TN in leachate was reduced up to 13.23%, 5.80%, and 2.67% in response to EM, EM+ 5%G, and EM+ 10%G, respectively, compared to the control. These results indicate that EM combined with G as soil amendments can reduce leaching of nutrients and further support the regulation of a coastal saline soil pH and EC.     

设施农业棚室空间烟雾的分布及沉降(简报)

运用气液二相流喷雾技术,以常温烟雾为载体喷施农药,是设施农业病虫害防治作业的新技术。其雾化特点是雾滴粒径很细、在空中悬浮的时间很长。为了掌握烟雾运动、分布、沉积的规律,该文用髙浓度的黑色素水溶液喷雾后对空气中药物的质量密度用大气采样器、分光光度计进行了测试分析。获得了描述药物烟雾作业性能、技术特征的主要参数及经济实用的测试方法。探知了空间药物质量密度随棚室长度及时间的变化规律、以及雾滴的沉降规律。研究表明该测试方法简易可行,并为解析喷雾流场,求得最佳喷雾方案和评价喷雾质量、效果提供了参考。     

模拟酸雨和酸雾对水稻生理和生长的影响

模拟酸雨和酸雾（ｐＨ２．０～５．６）的土培试验结果表明，低ｐＨ酸雨和酸雾处理对水稻产生明显伤害，水稻叶片出现坏死斑点，细胞膜透性增大，汁液ｐＨ值明显下降，叶绿素含量和光合速率明显降低，并随酸雨和酸雾的酸度增大、处理剂量增加而加重；叶片Ｎ，Ｐ和Ｋ养分被淋失，生长受抑制，产量明显下降。酸雨和酸雾处理诱导叶片过氧化物酶、过氧化氢酶和抗坏血酸氧化酶活性增高，但不同酶的活性峰值出现在不同的处理酸度梯度上。相同酸度下，对水稻生长的抑制作用以酸雾大于酸雨。     

滨海盐碱地的改良与景观植物筛选研究

滨海盐碱度高,很难为植物提供所需土壤养分,使得植物种类单一,造成滨海盐碱地景观缺失。本文主要对滨海盐碱土的改良应用进行研究,通过学习滨海盐碱地成因,分析景观缺失现象,借助文献数据库及相关网络共享对近代科研人员在滨海盐碱地的研究进展及成果进行总结。探讨景观植物的引种筛选,实现在营造滨海景观的同时改良盐碱地,旨在为今后植物对滨海盐碱地的改良提供新的思路。     

滨海盐土暗管排水降渍脱盐效果研究

在江苏省滨海盐土按不同埋深和间距埋设地下暗管,其降渍、脱盐作用主要表现在丰水期(7～9月)内,在试验范围内,10 m间距暗管的降渍效果最显著,但与15 m间距暗管的脱盐效果相差不明显;在较小间距(10 m)时,1.4 m埋深暗管的降渍效果优于1.2 m埋深,埋设间距≥15 m后,埋深对暗管降渍效果无明显影响,而在所有埋设间距处理中,1.4 m埋深暗管的脱盐效果均优于1.2 m埋深。综合比较分析各相关试验结果,并考虑暗管埋设的初期投资和后期维护成本,推荐间距15 m、埋深1.4 m为江苏滨海盐土降渍脱盐的地下暗管工程最佳布设参数。