面向生态系统结构的生物多样性保护成效空间对比评估

开展生物多样性保护成效对比评估对于合理执行生态补偿机制的转移支付政策,以及进一步促进全国生态保护管理水平的有效提升都具有重要意义。以2015年版《全国生态功能区划》划定的生物多样性保护重要生态功能区为研究对象,采用生物多样性保护成效结构指数,探讨重要生态功能区生物多样性保护成效的区域分异情况。研究结果表明：(1)华南、华东与华中地区重要生态功能区的生态结构参照基准较高,东北地区重要生态功能区居中,较差的重要生态功能区则位于西南和西北地区,说明了全国生态环境本底的区域分异性;(2)西北和西南地区重要生态功能区的保护成效结构指数较高,华中和华南地区居中,而东北和华东地区的保护成效结构指数较低,体现了2015年全国重要生态功能区生物多样性保护成效的空间差异情况;(3)从草原、森林与湿地生物多样性的保护成效结构指数来看,西北与西南地区、东北和西南地区及华东地区的重要生态功能区分别具有较大优势。上述研究结果反映了全国重要生态功能区生物多样性保护成效优劣的空间差异状况,可为政府部门健全生态补偿机制以及制定生态系统恢复方案提供决策参考。     

Do biogeographic parameters matter? Plant species richness and distribution of macrophytes in relation to area and isolation of ponds in NW Polish agricultural landscape

Effects of pond size and isolation on total vascular plant species richness and number of obligate wetland species were compared. Subsequently, the potential for the presence of spatial patterns in wetland species distribution among ponds in an agricultural landscape was explored. Relationships between species richness and two main biogeographic parameters were analysed using simple and multiple linearised regression models. Spatial patterns were looked for by means of analyses carried out with the R CRAN software (join-count statistics). Simple regression analyses performed on the regional scale (n = 50) revealed the significance of the effect of pond size only (r = 0.46 for total plant species richness and r = 0.28 for wetland species richness vs. pond area). Further analyses conducted on the local scale identified the best multiple regression models in the largest pond cluster (n = 20); the models showed statistical significance of relationships between the species richness and both independent variables (r = 0.80 for total plant species richness and r = 0.70 for wetland species richness vs. pond area and isolation, including mean distance to the nearest ten ponds). Spatial analyses were performed for 26 obligate wetland species selected from 149 species recorded in all the 50 ponds. Exploratory spatial data analysis revealed the presence of significant positive spatial autocorrelation in the distribution of 8 species. In such cases, it is possible to reject the random distribution hypothesis, which justifies exploration of spatial regimes. In practice, correct spatial model specifications may have implications for predicting species occurrences under changing environmental conditions, e.g. changes in the number of ponds.     

Characteristic community structure of Florida’s subtropical wetlands: the Florida wetland condition index for depressional marshes, depressional forested, and flowing water forested wetlands

Land use and land cover change has a marked affect on wetland condition, and different wetland types are affected differentially depending on many abiotic and biotic variables. To assess wetland condition, we have developed a Florida wetland condition index (FWCI) composed of indicators of community structure in the diatom, macrophyte, and macroinvertebrate assemblages for 216 wetlands (n = 74 depressional marsh, n = 118 depressional forested, n = 24 flowing water forested wetlands). Depressional wetlands located along a human disturbance gradient throughout Florida were sampled for each assemblage. Forested flowing water wetlands were sampled for macrophytes only. The landscape development intensity index (LDI) was used to quantify the human disturbance gradient. In general, human disturbance in adjacent areas had the greatest impact on depressional herbaceous wetlands, followed by depressional forested wetlands. Forested flowing water wetlands (i.e., forested strands and floodplain wetlands) were less affected by local conditions, with most of their changes in wetland condition correlated with alterations at the larger watershed scale. Strong correlations between the FWCIs and LDI index scores suggest that changes in community structure can be detected along a gradient of human land use activities adjacent to wetland ecosystems.     

Diversity patterns of seasonal wetland plant communities mainly driven by rare terrestrial species

In cleared landscapes, wetlands can represent important reservoirs of native plant diversity, which include terrestrial species. Depending on study aims, non-wetland plants might be removed before analysis, affecting conclusions around biodiversity and community structure. We compared the native plant communities of seasonal wetlands in a predominately agricultural landscape as defined geographically (including all species) with that of the obligate wetland assemblage. We were primarily concerned with determining how this design decision affects ecological and conservation conclusions. We analysed a survey database containing >12,900 flora records from South Australia, developing a new area-based method to remove sampling bias to include only wetlands with a near-complete census. We modelled occupancy, species-area relationships, β-diversity and nestedness under our contrasting community definitions. Terrestrial species were 57.4 % of total richness. Removing these species reduced wetland α-diversity by 45 %, but did not affect the scaling of richness with area (power-law species-area relationship z = 0.21 ± 0.01). Occupancies for wetland plants were relatively uniform, but were heavily dominated by rare (satellite) species when terrestrial plants were included, and this also increased β-diversity. Nestedness for terrestrial species occupancies was marginally lower than predicted under null models, suggesting that rare species often do not co-occur with common species. An implication of these occupancy patterns is that twice as many wetlands (and 50 % more wetland area) would be needed to include every native species within at least one wetland compared with wetland-only species.     

Can <Emphasis Type="Italic">Bradyrhizobium</Emphasis> strains inoculation reduce water deficit effects on peanuts?

Drought is one of the environmental factors that most affects peanut cultivation in semi-arid regions, resulting in economic losses to growers. However, growth promoting bacteria are able to reduce water deficit damage in some plant species. In this context, this study aimed to evaluate the interaction of Bradyrhizobium strains reducing water stress effects on peanut genotypes by antioxidant enzymes activities, leaf gas exchanges and vegetative growth, as well as to determine the taxonomic positioning of strain ESA 123. The 16S rRNA gene of ESA 123 was amplified by PCR and sequenced by dideoxy Sanger sequencing method. An experiment was performed in greenhouse with three peanut genotypes (BRS Havana, CNPA 76 AM and 2012-4), two Bradyrhizobium strains (SEMIA 6144 and ESA 123), a mineral source of N and an absolute control (without N) under two water regimes (with and without irrigation). Seeds of peanut were sown and the plants were grown until 30 days after emergence. On the 20th day, the water deficit plants group had their irrigation suspended for 10 days. At in silico analyzes, ESA 123 presented 98.97% similarity with the type strain of B. kavangense. Leaf gas exchange was affected by water deficit; as well as alteration of antioxidant activities and reduction of vegetative growth variables. However, some plants inoculated with SEMIA 6144 and ESA 123 strains presented lower reductions and increment of some evaluated variables, mainly the ones inoculated with the ESA 123 strain, Bradyrhizobium sp. from the semi-arid region of Northeast Brazil. This data suggests beneficial effects of the peanut-Bradyrhizobium interaction in a water stress condition, specially with the ESA 123 strain.     

Influence of ethnic traditional cultures on genetic diversity of rice landraces under on-farm conservation in southwest China

Background

Crop genetic resources are important components of biodiversity. However, with the large-scale promotion of mono-cropping, genetic diversity has largely been lost. Ex-situ conservation approaches were widely used to protect traditional crop varieties worldwide. However, this method fails to maintain the dynamic evolutionary processes of crop genetic resources in their original habitats, leading to genetic diversity reduction and even loss of the capacity of resistance to new diseases and pests. Therefore, on-farm conservation has been considered a crucial complement to ex-situ conservation. This study aimed at clarifying the genetic diversity differences between ex-situ conservation and on-farm conservation and to exploring the influence of traditional cultures on genetic diversity of rice landraces under on-farm conservation.

Methods

The conservation status of rice landrace varieties, including Indica and Japonica, non-glutinous rice (Oryza sativa) and glutinous rice (Oryza sativa var. glutinosa Matsum), was obtained through ethno-biology investigation method in 12 villages of ethnic groups from Guizhou, Yunnan and Guangxi provinces of China. The genetic diversity between 24 pairs of the same rice landraces from different times were compared using simple sequence repeat (SSR) molecular markers technology. The landrace paris studied were collected in 1980 and maintained ex-situ, while 2014 samples were collected on-farm in southwest of China.

Results

The results showed that many varieties of rice landraces have been preserved on-farm by local farmers for hundreds or thousands of years. The number of alleles (Na), effective number of alleles (Ne), Nei genetic diversity index (He) and Shannon information index (I) of rice landraces were significantly higher by 12.3–30.4 % under on-farm conservation than under ex-situ conservation. Compared with the ex-situ conservation approach, rice landraces under on-farm conservation programs had more alleles and higher genetic diversity. In every site we investigated, ethnic traditional cultures play a positive influence on rice landrace variety diversity and genetic diversity.

Conclusion

Most China’s rice landraces were conserved in the ethnic areas of southwest China. On-farm conservation can effectively promote the allelic variation and increase the genetic diversity of rice landraces over the past 35 years. Moreover, ethnic traditional culture practices are a crucial foundation to increase genetic diversity of rice landraces and implement on-farm conservation.

     

A review of 15 years of <Emphasis Type="Italic">Spartina</Emphasis> management in the San Francisco Estuary

Regional, ecosystem-level conservation projects with significant vegetation management components require planning, coordination, and responsive management strategies to minimize negative impacts and maximize ecological benefits over time. The California State Coastal Conservancy’s Invasive Spartina Project (ISP) offers an example of a complex, ecosystem-scale weed eradication effort guided by regional conservation goals. We review the management framework developed by the ISP, describe decision thresholds used for site-specific management transitions over the project’s 15 years, and present strategies being used to address major challenges to project completion. These strategies include developing genetics and weed mapping approaches to aid with identification of hybrids between the introduced Spartina alterniflora and the native Spartina foliosa. The ISP also developed a tidal marsh restoration project to enhance habitat for an endangered bird, the California Ridgway’s rail (Rallus obsoletus obsoletus), that uses tall, dense forms of hybrid Spartina as high tide refugia and nesting substrate. By 2014, the ISP had installed over 300,000 native plants and recorded a greater than 96 % estuary-wide reduction in hybrid Spartina (from 323 ha to 12 net ha) despite treatment restrictions imposed at 11 sites since 2011 to protect the rail. Approximately 80 % of the remaining hybrid Spartina occurs in areas currently restricted from treatment, delaying project completion. The successes and setbacks of the ISP illustrate the complexities of achieving ecosystem-level conservation goals dependent on large-scale vegetation management.     

Microbial ecoenzyme stoichiometry,nutrient limitation,and organic matter decomposition in wetlands of the conterminous United States

Microbial respiration (R_m) and ecoenzyme activities (EEA) related to microbial carbon, nitrogen, and phosphorus acquisition were measured in 792 freshwater and estuarine wetlands (representing a cumulative area of 217,480 km²) across the continental United States as part of the US EPA’s 2011 National Wetland Condition Assessment. EEA stoichiometry was used to construct models for and assess nutrient limitation, carbon use efficiency (CUE), and organic matter decomposition (? k). The wetlands were classified into ten groups based on aggregated ecoregion and wetland type. The wetlands were also assigned to least, intermediate, and most disturbed classes, based on the extent of human influences. Ecoenzyme activity related to C, N and P acquisition, R_m, CUE, and ? k differed among ecoregion–wetland types and, with the exception of C acquisition and ? k, among disturbance classes. R_m and EEA were positively correlated with soil C, N and P content (r = 0.15–0.64) and stoichiometry (r = 0.15–0.48), and negatively correlated with an index of carbon quality (r = ? 0.22 to ? 0.39). EEA stoichiometry revealed that wetlands were more often P- than N-limited, and that P-limitation increases with increasing disturbance. Our enzyme-based approach for modeling C, N, and P acquisition, and organic matter decomposition, all rooted in stoichiometric theory, provides a mechanism for modeling resource limitations of microbial metabolism and biogeochemical cycling in wetlands. Given the ease of collecting and analyzing soil EEA and their response to wetland disturbance gradients, enzyme stoichiometry models are a cost-effective tool for monitoring ecosystem responses to resource availability and the environmental drivers of microbial metabolism, including those related to global climate changes.     

Effects of Pleistocene climate change on genetic structure and diversity of <Emphasis Type="Italic">Shorea macrophylla</Emphasis> in Kalimantan Rainforest

The island of Borneo is the diversity center of the Dipterocarpaceae, the most important family of tropical rainforest trees in Southeast Asia. However, changes in land use and climate have affected dipterocarp distributions on the island, raising concerns about the vulnerability (inter alia) of the endemic riparian species Shorea macrophylla. Thus, to aid conservation efforts, we have investigated the genetic diversity, structure, and demographic history of S. macrophylla. The species’ genetic diversity and structure in Kalimantan (part of Indonesia, covering 75% of the island) were explored by examining genotypes of 377 individuals representing 13 populations in three regions (Northeast, Central, and West Kalimantan) using 14 newly developed microsatellite loci. Higher genetic diversity was found, at all loci, in samples from Northeast Kalimantan than in samples from the other regions. Moderate genetic differentiation between populations was detected (F_ST 0.093). Bayesian clustering, principal coordinate, and neighbor joining tree analyses of the population structure consistently identified two genetically distinct groups, one in the Northeast and the other in the Central and West regions. The higher diversity of the diverged populations in Northeast Kalimantan indicates that the region may have hosted rainforest refugia during the ice age. Accordingly, analysis using DIY ABC software indicated that the Northeast and Central-West Kalimantan groups diverged 194,000 years ago. We conclude that global climate change during the Pleistocene strongly influenced the genetic diversity and structure of S. macrophylla populations in Kalimantan.     

全国重要生态功能区生物多样性保护成效区域对比评估

国家重要生态功能区是国家主体功能区战略实施和生态保护红线划定的基础,关系到全国乃至全球范围的生态安全。开展大尺度生物多样性保护成效区域对比评估对促进物种栖息地科学管理、提升国家生物多样性保护水平具有较为重要的意义。本研究以2015年《全国生态功能区划》修编版划定的24个生物多样性保护生态功能区为研究对象,选取生态功能区内或邻近生态功能区的国家级自然保护区核心区作为参照区,利用InVEST模型计算多年参照区生境质量指数,并从中筛选出最大值,构建全国尺度的生境质量指数参照基准,在此基础上,采用空间叠加分析方法建立保护成效指数,定量分析了24个重要生态功能区生物多样性保护成效空间对比差异。研究结果表明:(1)基于参照基准的生物多样性保护成效区域对比评估方法可以较好地应用于全国尺度,全国重要生态功能区生境质量指数参照基准呈现明显的"西北低,东南高"的分布格局,而重要生态功能区生物多样性保护成效则表现出"西北高,东南低"的空间差异;(2)位于华东和华南地区的重要生态功能区生态环境本底状况较好,东北和华中地区的重要生态功能区居中,而西北和西南地区的重要生态功能区生态环境本底状况较差;(3)2015年西北和西南地区的重要生态功能区生境质量指数基本与参照基准持平,表现为生物多样性保护成效较好,华中和华南地区的重要生态功能区生境质量指数小幅度低于参照基准,体现保护效果居中,保护效果较差的重要生态功能区则位于东北与华东地区,其生境质量指数大幅度低于参照基准。通过对全国尺度重要生态功能区生物多样性保护成效区域对比评估,为进一步完善国家生物多样性保护成效的绩效考评机制和转移支付提供科学依据。     

基于空间分析的东北地区湿地优先恢复

以GIS/RS为技术手段,从景观结构因子、河流及道路密度、湿度指数、地貌条件、耕地生产力5方面对东北地区湿地恢复潜力进行空间分析,确定了东北地区湿地恢复的优先、次优先区域,并利用农作物生产与湿地协调发展指数、景观指数验证恢复效果.结果表明： 东北地区湿地优先恢复面积为1.78×10⁶ hm²,其中,耕地和草地为主要的恢复类型,占优先恢复面积的96.7%,主要位于东北部的三江平原和中部的松嫩平原;次优先湿地恢复面积为1.03×10⁶ hm².经过优先、次优先湿地恢复,东北地区湿地面积将在现有湿地面积的基础上提高37.4%.湿地恢复后,研究区农作物生产与湿地协调发展水平值从恢复前的0.539增加到恢复后的0.733,湿地景观格局更有利于沼泽湿地生态功能的发挥.说明基于空间分析制定的东北地区湿地恢复方案是可行的,可为东北地区湿地恢复的实施和生态环境的改善提供数据支持.     

Fine-scale spatial genetic structure in the frankincense tree <Emphasis Type="Italic">Boswellia papyrifera</Emphasis> (Del.) Hochst. and implications for conservation

The fine-scale genetic structure and how it varies between generations depends on the spatial scale of gene dispersal and other fundamental aspects of species’ biology, such as the mating system. Such knowledge is crucial for the design of genetic conservation strategies. This is particularly relevant for species that are increasingly fragmented such as Boswellia papyrifera. This species occurs in dry tropical forests from Ethiopia, Eritrea and Sudan and is an important source of frankincense, a highly valued aromatic resin obtained from the bark of the tree. This study assessed the genetic diversity and fine-scale spatial genetic structure (FSGS) of two cohorts (adults and seedlings) from two populations (Guba-Arenja and Kurmuk) in Western Ethiopia and inferred intra-population gene dispersal in the species, using microsatellite markers. The expected heterozygosity (H _E) was 0.664–0.724. The spatial analyses based on kinship coefficient (F _ij) revealed a significant positive genetic correlation up to a distance of 130 m. Spatial genetic structure was relatively weak (Sp = 0.002–0.014) indicating that gene dispersal is extensive within the populations. Based on the FSGS patterns found, we estimate indirectly gene dispersal distances of 103 and 124 m for the two populations studied. The high heterozygosity, the low fixation index and the low Sp values found in this study are consistent with outcrossing as the (predominant) mating system in B. papyrifera. We suggest that seed collection for ex situ conservation and reforestation programmes of B. papyrifera should use trees separated by distances of at least 100 m but preferably 150 m to limit genetic relatedness among seeds from different trees.     

Assessing the distribution and conservation status of a long-horned beetle with species distribution models

Data shortfalls on species distribution affect species differently, but it is frequent among insects. Species distribution models (SDMs) are important tools to fill biogeographic deficits and provide support for practical conservation actions, particularly for cryptic or hard to survey species. We employed SDMs to evaluate one such species, the long-horned beetle (Macrodontia cervicornis), listed as ‘vulnerable’ in the IUCN’s Red List of Threatened Species. Given new distributional data for this species, we applied three different SDMs to: (1) provide the first assessment of this species’ distribution and potential dispersal routes; (2) evaluate the effectiveness of the current South American protected areas system for its conservation; and (3) discuss its potential distribution, as well as historical, biogeographical, and taxonomic issues related to it. Our models reached fair True Skilled Statistics values (TSS > 0.5), with the core area for M. cervicornis located in the Amazon forest, although suitable areas were also predicted along the Atlantic forest. Areas in the dry diagonal South American corridor (dry biomes of Cerrado, Caatinga, and Pampas) in South America were not predicted as suitable. The preference of M. cervicornis for humid areas with high temperatures may guarantee a better physiological control for dehydration, considering that large insects are more affected by water loss. In general, approximately 15 % of the distribution of M. cervicornis is in humid protected areas. The disconnected distribution of the long-horned beetle may be an indication of the existence of cryptic species under the same classification. We suggest that similar studies with other insect groups (e.g. butterflies, bees) should be conducted to properly assess their distributions, conservation status, and responses to hot-humid gradients throughout South America.     

典型气候条件下东北地区生态系统水源涵养功能特征

东北地区是我国重要的生态功能区,其包含的典型生态系统具有独特的水源涵养功能,在防洪减灾,保障生态安全和人居安全中发挥着关键作用。以往有关水源涵养功能的研究主要是依托不同水文模型方法,从单一年份或多个年份的角度进行研究,较少考虑不同气候条件下水源涵养功能的空间分异特征。采用标准化降水蒸散发指数(Standardized Precipitation Evapotranspiration Index,SPEI)划分研究区的典型气候年份(干旱、正常和湿润);基于水量平衡法,结合SCS-CN模型以及Penman-Monteith方程对东北地区典型气候条件下生长季内的水源涵养功能进行研究。结果表明:(1)研究区水源涵养功能在不同气候条件下差异明显,三个典型气候年份生长季内的水源涵养总量分别为:干旱年(SPEI=-1.26)为2214.64亿m~3、正常年(SPEI=-0.22)为3231.49亿m~3和湿润年(SPEI=1.05)为3969.33亿m~3。(2)水源涵养功能空间变异突出,但在三种典型气候条件下呈现出一致变化,均表现为长白山地区水源涵养量最大,大小兴安岭地区次之,水源涵养量最低的地方主要出现在呼伦贝尔以西的草原地区,在东北平原的部分地区也有低值的出现,如白城、通辽、鸡西等地区,水源涵养量较一般的地方出现在东北平原大部分以农田为主的地区。(3)水源涵养功能除受气候因素的影响外,还取决于土地利用类型的变化,对于整个东北地区来讲,水源涵养总量表现为林地农田草地湿地,单位面积水源涵养量在干旱年和正常年表现为林地农田湿地草地,在湿润年份表现为林地湿地农田草地。研究结果揭示了东北地区三种典型气候条件下重要生态系统的水源涵养功能大小、空间分布特征及其主要驱动因素,可为区域生态空间规划和生态系统管理提供科学指导。     

Reproductive biology and management of two commercially important groupers in the SW Atlantic

The reproductive biology of Epinephelus morio (red grouper) and Mycteroperca bonaci (black grouper) were evaluated based on 533 specimens collected from artisanal fisheries landings in the Abrolhos Bank, Brazil, between May 2005 and September 2012. Sex ratio for the black grouper was 1:14 (n = 155 females and 11 males; 26.1–147 cm TL) and 1:10 for the red grouper (n = 334 females and 33 males; 15.0–96.0 cm TL). For both species, highest values of the gonadosomatic index (GSI) for females were recorded between July and October, indicating spawning during the austral winter. The length at first maturity (L₅₀) for females was estimated at 62.0 and 47.0 cm TL for the black and red grouper, respectively. Batch fecundity based on TL and TW ranged from 2 to 15.4^?10⁶ and 1.5 to 13.7^?10⁶ for the black and red grouper, respectively. Interviews with experienced fishers revealed that spawning seasons of both groupers are largely unrecognized. Results demonstrate a positive relationship between GSI peaks, lower temperatures and stronger winds. The information provided herein may help decision-making regarding fisheries management and conservation for E. morio and M. bonaci at various levels of governance in the Abrolhos Bank, the region with the largest and richest coralline reefs in the South Atlantic.     

Density of Primates in Four Semi-deciduous Forest Fragments of São Paulo,Brazil

Populational parameters of primates in the remaining southeastern Brazilian Atlantic Forest have been estimated, but investigations are biased to coastal evergreen sites. In this study density of three primate species was assessed through line-transect surveys in four semi-deciduous forest fragments (240 to 1450 ha) in Fazenda Barreiro Rico, eastern range of central Plateau of São Paulo state, Brazil. A total of 274 km was surveyed from January to October 2000. I estimated densities via DISTANCE software. Two of the largest fragments contained five primate species while two of the smallest ones harboured, respectively, four and two species. Densities of Cebus apella (15.34–47.92 ind./km²), Alouatta guariba (8.32–34.61), and Brachyteles arachnoides (19.92–35.11) were considerable. Differently from C. apella and A. guariba, B. arachnoides presented a density higher than previously estimated for the largest patch. The hypothetical minimum total population of B. arachnoides (601) may be the largest in semi-deciduous sites. This reinforces the value of the area in terms of its relative contribution for conservation of this endangered species. The narrow spatial scale distribution of forest fragments at Barreiro Rico and its proximity to academic institutions make the site suitable for programs of forest connectivity, studies on conservation biology, and wildlife management endeavours.     

Habitat monitoring of an endangered Asian butterfly, <Emphasis Type="Italic">Teinopalpus aureus</Emphasis> (Lepidoptera: Papilionidae) and change in local residents’ conservation awareness

Teinopalpus aureus (Lepidoptera: Papilionidae) is endemic to the mountains of southern China and Vietnam. This butterfly species was the focus of several high profile poaching cases in China and influenced conservation policies in the country because of this attention. In this study we closely monitored 2.25 km² of the butterfly’s known habitat in Mt. Dayao Nature Reserve, Guangxi Province, China, from 2012 to 2014. A total of 33 magnolia host plants were found in the plot, and 28 individuals were reared from the egg/early larval stage until they pupated or died. We found T. aureus sufficiently difficult to breed and failed to induce oviposition in captivity. In 2015, a public museum was built in Mt. Dayao Nature Reserve to raise conservation awareness of local biodiversity, which specifically featured an exhibition of T. aureus. To investigate whether the museum was effective in increasing local conservation awareness, in 2013, 2015 and 2017, a total of 1022 local residents were interviewed regarding their conservation awareness of the butterfly. Conservation awareness significantly increased with time from 2013 to 2017, but this was also strongly influenced by residence location and respondent age.     

The effects of forest succession and grazing intensity on bird diversity and the conservation value of a Northern Adriatic karstic landscape

We studied the effects of different land uses on conservation value and bird diversity in a Northern Adriatic karstic landscape. Our research area was situated in SW Slovenia and was covered with dry pastures and meadows in different stages of forest sucession and with different grazing intensities. We surveyed birds in 2007 and 2012 using the line transect method, with 50.4 km being covered each year. In the analysis we divided the survey transects into 200 m tiles which were used as statistical units in the analysis. We then modelled conservation value, bird diversity and bird abundances with different land uses; we used boosted regression trees as a modelling tool. Canonical correspondence analysis showed that a distinct group of birds occurred on tiles with higher grazing intensity. The species in this group also had significantly higher abundances in 2012 than in 2007. Forest succession was the most important predictor of SPA conservation value (Special Protected Areas according to the Directive on the conservation of wild birds of the European Union) and had negative effect on it; grazing intensity had a unimodal positive influence on conservation value and was most beneficial at low intensity. The model for the European conservation value showed a rather low predictive power. Farmland bird diversity was also negatively affected by forest and positively by grazing intensity. For the four Natura 2000 species—protected species in the SPA Kras (Woodlark Lullula arborea, Red-backed Shrike Lanius collurio, Corn Bunting Emberiza calandra and Skylark Alauda arvensis), forest cover also had a negative effect. Grazing intensity had a positive effect for Woodlark, Red-backed Shrike and Skylark. The highest SPA conservation value and farmland bird diversity could therefore be achieved in a landscape with as low a forest succession as possible and grazing present but at low intensity. We recommend inclusion of appropriate measures in the agri-environment schemes (CAP pillar II) of Rural Development Programmes of the countries in the region with similar areas. The payments should be sufficiently stimulative to reopen the large areas subject to forest encroachment in the Northern Adriatic hinterland.     

Ichthyofaunal Assemblage of the Dianshan Lake,Shanghai, China: Implications for Management

Ichthyofaunal diversity of the Dianshan lake in Shanghai, China was assessed during the year 2013 from samples of finfish harvested using fleets of gillnets and trawls of different mesh sizes with the aim of generating necessary data that could support sustainable use of finfish in this lake. Morphometric parameters of specimens caught were taken following standard procedures. Totally 21,308 specimens belonging to 40 species, 15 families and 7 orders were encountered throughout the study period. Seasonal abundance was lowest (395 individuals) during March (spring) and highest (4428 individuals) during August (summer). Cyprinidae was the dominant family (22 species) and Coilia ecetenes taihuensis was the most abundant species (30.69%), followed by Acheilognathus taenianalis (17.8618%), Plagiognathops microlepis (16.567%), Carassius auratus (14.492%). The evenness, richness and biodiversity of the faunal assemblage were also evaluated by Shannon–Wiener index (H′), Margalef’s diversity Index (d) and evenness index (J) respectively. Hypophthalmichthys nobilis was the largest and heaviest fish (34.909 cm, FL; 889.355 g, W), the smallest fish in length recorded was Odontamblyopus rubicundus (4.19 cm) while Plecoglossus altivelis altivelis (1.1 g) was the lowest in terms of mean weight. The mean condition factor for all fish species was (K = 1.72), showing fish species were generally in ‘good’ condition. Fluctuations in species occurrence and abundance noted in our study may be accounted from the variation in the physico-chemical parameters of the Lake in respect to time. But, under such a situation it is evident that the small fish species increased to a great extent and a few like Coilia ecetenes taihuensis became the dominant.     

Distribution and diet of demersal Arctic Cod, <Emphasis Type="Italic">Boreogadus saida</Emphasis>, in relation to habitat characteristics in the Canadian Beaufort Sea

Arctic Cod (Boreogadus saida) occur throughout the circumpolar north; however, their distributions at localized scales are not well understood. The seasonal habitat associations and diet preferences across life-history stages of this keystone species are also poorly known, thereby impeding effective regulatory efforts in support of conservation objectives. The distribution of Arctic Cod in the Canadian Beaufort Sea was assessed using bottom trawling in shelf and slope habitats between 20 and 1000 m depths. Highest catch biomasses occurred at 350 and 500 m depth slope stations, coinciding with >0 °C temperatures in the Pacific–Atlantic thermohalocline and Atlantic water mass. Calanus glacialis, Calanus hyperboreus, Themisto libellula, and Themisto abyssorum were identified as key prey species in the diet of Arctic Cod, comprising approximately 86 % of total biomass in guts. Hierarchical cluster analysis with a SIMPROF test identified five statistically significant (p < 0.05) diet groups among gut samples. Arctic Cod shifted from a primarily Calanus diet at shelf stations (<200 m depth) to a Themisto diet in slope habitats (>200 m depth) coinciding with an associated increase in fish standard length with depth. Smaller Arctic Cod fed primarily on Calanus copepods and larger Arctic Cod fed primarily on the larger Themisto species. The habitat and diet associations presented here will inform knowledge of structural and functional relationships in Arctic marine ecosystems, aid in mitigation and conservation efforts, and will enhance our ability to predict the effects of climate change on the local spatial and depth associations of this pivotal marine fish.