粤港澳大湾区海岸带生态修复工程中的景感生态学应用分析

海岸带作为沿海地区的特有资源,不仅承担着生态保障、生产发展的功能,也是居民生活、休闲、娱乐的重要空间。景感生态学强调将人的物理感知、心理认知以及社会经济可持续发展理念融入到生态环境的规划、建设与管理中,对当前粤港澳大湾区海岸带生态修复工程具有指导意义。以粤港澳大湾区海岸带的18个生态受损点及修复工程为例,通过文献调研和实地踏查,开展其对居民的视觉、听觉、嗅觉、味觉、触觉等物理感知,以及心理认知等景感内涵方面的作用,总结了海岸带景感营造的实现思路与方法。研究认为将景感生态学理论与方法应用于海岸带生态修复工程规划、设计和建设全过程,有助于细化生态修复各层级具体目标,全面提升生态系统服务和提高生态产品质量,提升周边居民的满意度和幸福感。     

基于Google Earth Engine云计算的城市群生态质量长时序动态监测——以粤港澳大湾区为例

人类活动对生态环境的影响日益强烈,及时动态地监测生态现状及其变化信息对城市生态的管理和保护以及可持续发展具有重大意义。遥感生态指数(RSEI)是一种客观、快速和简便的生态质量监测和评价技术,已被广泛应用于生态学研究领域,但在进行大范围长时间监测时往往面临云遮挡和拼接困难的问题。因此,本文基于Google Earth Engine(GEE)平台,对1988—2018年来粤港澳大湾区共3530景Landsat遥感影像进行批量去云,采用中值合成法逐年计算绿度、湿度、干度和热度等遥感指标并利用主成分分析法构建遥感生态指数,评价了该区域近30年生态质量的时空变化。该方法改善了遥感生态指数在大范围长时序监测中数据缺失和拼接困难等问题,增加了时间序列的可比性。研究表明:(1)遥感生态指数能够较好地表征粤港澳大湾区的生态质量,其中绿度和湿度指标与其呈正相关,干度和热度指标与其呈负相关;(2)时间上,三十年间粤港澳大湾区生态质量呈"上升-下降-上升-下降"的波动下降趋势,空间上,生态质量具有明显的空间异质性,主要呈现西北和东北部高和中部低的状态。重度和中度退化区主要集中在区域中部,总体改善区域主要位于西...     

The action of prostaglandin E2 and F1α on myocardial ischaemia-infarction arrhythmias in the dog

Prostaglandin E₂ and F_1α infusions have been tested for their ability to reduce the arrhythmias associated with occlusion of the left descending coronary artery in the anaesthetised dog. At 1 μg/kg/min both PGs reduced the incidence of premature ventricular contractions occurring during 25-min occlusions, while not reducing the incidence of ventricular fibrillation occurring on occlusion release. When infused for 5-min periods at 1 to 16 μg/kg/min, neither PGE₂ nor PGF_1α effectively reduced the frequency of ventricular arrhythmias occurring 24 hr after a permanent coronary occlusion.     

Fine‐scale distribution modeling of avian malaria vectors in north‐central Kansas

Infectious diseases increasingly play a role in the decline of wildlife populations. Vector‐borne diseases, in particular, have been implicated in mass mortality events and localized population declines are threatening some species with extinction. Transmission patterns for vector‐borne diseases are influenced by the spatial distribution of vectors and are therefore not uniform across the landscape. Avian malaria is a globally distributed vector‐borne disease that has been shown to affect endemic bird populations of North America. We evaluated shared habitat use between avian malaria vectors, mosquitoes in the genus Culex and a native grassland bird, the Greater Prairie‐Chicken (Tympanuchus cupido), by (1) modeling the distribution of Culex spp. occurrence across the Smoky Hills of north‐central Kansas using detection data and habitat variables, (2) assessing the occurrence of these vectors at nests of female Greater Prairie‐Chickens, and (3) evaluating if shared habitat use between vectors and hosts is correlated with malarial infection status of the Greater Prairie‐Chicken. Our results indicate that Culex occurrence increased at nest locations compared to other available but unoccupied grassland habitats; however the shared habitat use between vectors and hosts did not result in an increased prevalence of malarial parasites in Greater Prairie‐Chickens that occupied habitats with high vector occurrence. We developed a predictive map to illustrate the associations between Culex occurrence and infection status with malarial parasites in an obligate grassland bird that may be used to guide management decisions to limit the spread of vector‐borne diseases.     

Predators of Greater Sage‐Grouse nests identified by video monitoring

ABSTRACT Nest predation is the primary cause of nest failure for Greater Sage‐Grouse (Centrocercus urophasianus), but the identity of their nest predators is often uncertain. Confirming the identity of these predators may be useful in enhancing management strategies designed to increase nest success. From 2002 to 2005, we monitored 87 Greater Sage‐Grouse nests (camera, N= 55; no camera, N= 32) in northeastern Nevada and south‐central Idaho and identified predators at 17 nests, with Common Ravens (Corvus corax) preying on eggs at 10 nests and American badgers (Taxidea taxis) at seven. Rodents were frequently observed at grouse nests, but did not prey on grouse eggs. Because sign left by ravens and badgers was often indistinguishable following nest predation, identifying nest predators based on egg removal, the presence of egg shells, or other sign was not possible. Most predation occurred when females were on nests. Active nest defense by grouse was rare and always unsuccessful. Continuous video monitoring of Sage‐Grouse nests permitted unambiguous identification of nest predators. Additional monitoring studies could help improve our understanding of the causes of Sage‐Grouse nest failure in the face of land‐use changes in the Intermountain West.     

Morphological convergence and coexistence in three sympatric North American species of Microtus (Rodentia: Arvicolinae)

Aim  Niche theory predicts that ecologically identical species cannot stably coexist in local communities. My aim was to investigate morphological diversity as a possible factor enabling the coexistence of a species-rich Microtus (Rodentia: Arvicolinae) fauna in a hotspot of North American mammalian diversity, the Greater Yellowstone Ecosystem (GYE).
Location  The Greater Yellowstone Ecosystem, North America.
Methods  Using in-hand morphological measurements of size and shape, I compared the morphologies of three North American vole species ( Microtus spp.), in sympatry in the GYE and in allopatry across their ranges, in order to examine: (1) whether morphologies are fixed or plastic and (2) the degree of morphological character displacement or convergence in sympatric species.
Results  Support was found for plasticity of morphology for all three vole species: M. longicaudus , M. montanus and M. pennsylvanicus. However, Microtus individuals of all species from the GYE area of sympatry were more similar to each other than to allopatric individuals of the same species.
Main conclusions  Competition among these congeners is not manifested in morphological overdispersion. The response of these congeneric species to the same local ecological conditions is convergent. The relative strength of environmental conditions appears to be stronger than the strength of competitive interactions among the study species.     

大仓鼠DNA 指纹谱探针的筛选

采用一种简便提取高质量DNA 的方法, 从大仓鼠肝脏组织中提取其总DNA , 分别以人工合成的微卫星核心序列(GTG)₅和(CA)₈做单一引物, 进行特异引物PCR 反应。电泳检测后回收15 条特异性片段。与被标记过的大仓鼠基因组DNA 反向杂交结果表明, 15 个片段中(GTG)_5-8 、(CA)_8-1b和(CA_{) 8-5b}产生了较强的阳性信号。我们依据3 个片段的测序结果设计适合DIG标记的探针, 该探针得到的大仓鼠不同地理种群个体的指纹图谱有较高的个体特异性和种群多态性, 而且与传统的来源于其它生物重复序列的探针如33.6 和33.15 形成的指纹图谱相比得到的变异适中, 便于统计。     

GRAY WHALE (ESCHRICHTIUS ROBUSTUS) HABITAT UTILIZATION AND PREY SPECIES OFF VANCOUVER ISLAND, B. C.

Habitat utilization and prey species of Vancouver Island gray whales were investigated by (1) summarizing 26 yr of distribution and feeding data and (2) conducting intensive observations in Clayoquot Sound, Vancouver Island, from 1989 to 1996. Whale distribution and movements were monitored from March to November through systematic boat surveys and whale-watch sighting programs. Prey species were collected by suction hose and plankton net or determined through analysis of fecal samples. Gray whales utilized virtually all of the southern west coast of Vancouver Island over the 26-yr observation period. Distribution, prey species, and feeding behavior showed marked variability during any one season and between years. Some feeding areas were used on an annual basis, others with >10-yr intervals between use. Feeding occurred in shallow sand or mud bays, eel grass beds, kelp beds, in the open water column, and at the surface. Young whales appeared to utilize habitat and prey species differently than adults. Main prey species included herring eggs/larvae ( Clupea harengus pallasi ), crab larvae ( Cancer magister megalops, Pachycbeles spp. zoea), mysids ( Holmesimysis sculpta, Neomysis rayii, Acanthomysis spp.), amphipods ( Ampelisca spp., Atylus borealis ), and ghost shrimp ( Callianassa californiensis ). The definition and relative importance of specific feeding grounds and the study of human impacts on this population are complicated by its broad and variable use of habitat and prey species.