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1.
Abstract. The estuarine ecosystem of the Amvrakikos Gulf, a semi-enclosed embayment of the Ionian Sea, was surveyed at 9 stations in June, 1980. Quantitative and qualitative relationships among the phytoplanktonic, zooplanktonic and benthic populations were examined and related to environmental parameters. It was found that quantitative maxima of each of the three components occurred at different stations. When stations were grouped according to a similarity index of each community, it could be shown that the stations were very similar with regard to phytoplankton and slightly less similar with regard to zooplankton. The stations differed considerably as far as the benthos is concerned. The phytoplankton also exhibited a lower species diversity (0.08-0.82 bits-indiv.-1 ) than the zooplankton (1.08-2.10 bits indiv.-1 ) and the benthos (0.85-5.06 bits indiv.-1 ). Differences in salinity among stations showed no significant correlation with the abundance or species diversity of phytoplankton, zooplankton or benthos. 相似文献
2.
Description of the Phytoplanktonic Community of the Oligotrophic Waters of the SE Aegean Sea (Mediterranean) 总被引：2，自引：0，他引：2
Abstract. A seasonal sampling program of five stations off the Island of Rhodes (SE Aegean Sea) was carried out in 1983–1984. Temperature, salinity, Secchi disk transparency, P-PO4 , N-NO3 , N-NO2 , N-NH3 , Si-SiO2 , and chl a were measured and phytoplankton species recorded. Cell concentrations and chl a varied seasonally. with the highest values in summer (l.2 times 104 -1- -1 total mean cells; 0.13 mgam-3 total mean chl a ) and the lowest in winter (2.3 times 103 , 1- -1 total mean cells; 0.06 mg. m-- total mean chl a ). A variation in cell abundance among stations was also noted. Quantitative relationships among the recorded taxa showed that diatoms and dinoflagellates were richer in species composition (88 and 58 total species, respectively) than coccolithophores (8 species) and other flagellates (8 species). Comparison of phytoplankton samples from different depths and stations by cluster analysis showed an irregularity or discontinuity in species associations. The SE Aegean Sea was characterized as oligotrophic on the basis of the estimated nutrient and phytoplankton concentration levels. 相似文献
3.
Sevim Polat 《Marine Ecology》2002,23(2):115-126
Abstract. The monthly changes in chlorophyll a , phytoplankton abundance and nutrient concentrations at two stations, one at the inshore and the other at the deep waters of the northern part of İskenderun Bay, were investigated between 1994 – 1995. The vertical distribution of nutrients and phytoplankton biomass were also studied at the deep station. The concentrations of NO3 +NO2 -N, PO4 -P and SiO4 -Si of surface water at both stations were 0.31 – 1.63 µg-at · l-1 , 0.08 – 0.60 µg-at · l-1 and 0.50 – 2.7 µg-at · l-1 , respectively. The highest concentrations were measured at the inshore station and clear differences were found between the inshore and deep-water stations. Chlorophyll a concentrations ranged from 0.17 to 2.78 µg · l-1 and the highest value was measured in March. At the inshore station, which was affected by land run-off, phytoplankton abundance reached the highest value (21,308 cells · l-1 ) in October 1995, with a marked dominance of Pseudonitzschia pungens (20,200 cells · l-1 ). The nutrient and chlorophyll a concentrations at the inshore station were higher than those at the deep station. One reason for this is the land-based nutrient input into the coastal area here. In spite of these effects, the bay is not eutrophicated because of circulation events in the northeastern Mediterranean. 相似文献
4.
Abstract. Studies on leaf growth and production were performed in two stands, at depths of 5 m and 22m, in the Posidonia oceanica (L.) D elile bed off Lacco Ameno, Ischia (Gulf of Naples). Experiments were carried out in situ from May 1988 to August 1989 at monthly intervals.
Leaf growth and production profiles differed in the two stands investigated. Growth rates were higher at 5 m, with a peak in autumn (5.8 mg · shoot-1 · d-1 ) and another in March (3.8 mg · shoot-1 · d-1 ). At 22 m the maximum rate occurred in May (3.9 mg · shoot-1 · d-1 ). These differential growth rates resulted in a delayed maximum leaf surface and biomass at the deep stand, where lower irradiance values and different temperature patterns were also found. The biomass of epiphytic algae showed trends similar to those of leaves; however, there were remarkable differences in the values between the two stations and for the two investigated years.
The production data of the present study are compared with those of other reports, and it is shown that growth processes are greatly influenced by physical factors. 相似文献
Leaf growth and production profiles differed in the two stands investigated. Growth rates were higher at 5 m, with a peak in autumn (5.8 mg · shoot
The production data of the present study are compared with those of other reports, and it is shown that growth processes are greatly influenced by physical factors. 相似文献
5.
Abstract. This paper briefly summarises research carried out in 1982–1990 in the coastal area off Monte Conero, SW northern Adriatic Sea. Oceanographic data on temperature, salinity, oxygen saturation, nutrients (nitrates, silicates and orthophosphates), and chlorophylls were collected to characterise this coastal ecosystem in view of the setting up of the "Costa del Monte Conero" protected marine area.
Towards the coast the physical and chemical parameters exhibited a seasonal periodicity.
Temperature showed a clear annual periodicity with a certain interannual variability; this also holds true for oxygen saturation, with peaks in March and minima in September, though without hypoxic events.
Nutrient concentrations peaked at the surface layer at the coastal station from December to March (nitrates: 35–50 μmol 1−1 ; silicates: 22–70 μmol 1−1 ; orthophosphates: 0.37–0.54 μmol 1−1 ) and minima in summer (Jul-Aug) on surface and bottom (0–12μmol 1−1 , 0–18.5 μmol 1−1 , and 0–0.15 μmol 1−1 , respectively). From 1988 to 1990 nutrient peaks were lower and coastal salinity exceed 33, with nitrates below 16 μmol 1−1 , silicates below 8 μmol 1−1 , and orthophosphates less than 0.2 μmol 1−1 .
In the coastal area of Senigallia, 40 km to the north, where the influence of the coastal current that carries the river inflows to the south is stronger, the seasonal cycle was similar, albeit with higher values for nutrients and chlorophylls. 相似文献
Towards the coast the physical and chemical parameters exhibited a seasonal periodicity.
Temperature showed a clear annual periodicity with a certain interannual variability; this also holds true for oxygen saturation, with peaks in March and minima in September, though without hypoxic events.
Nutrient concentrations peaked at the surface layer at the coastal station from December to March (nitrates: 35–50 μmol 1
In the coastal area of Senigallia, 40 km to the north, where the influence of the coastal current that carries the river inflows to the south is stronger, the seasonal cycle was similar, albeit with higher values for nutrients and chlorophylls. 相似文献
6.
Role of Bacteria in the Carbon and Nitrogen Flow between Water-Column and Sediment in a Shallow Marine Bay (Bay of Piran, Northern Adriatic Sea) 总被引：2，自引：0，他引：2
Abstract. The interdependences between phytoplankton standing crop, bacterial biomass and the dissolved organic matter (DOM) pool in the water column were investigated and related to sediment parameters in a shallow marine bay (Bay of Piran, Northern Adriatic Sea) over an annual cycle. Bacterioplankton density varied between 1–10 × 105 cells ml-1 , with lowest density observed in March corresponding to the low Chi a concentrations during this period. Generation times as determined by dialysis incubations ranged between 4h (June) and 82 h (March). Mean bacterial secondary production rates during summer were about 40 mg C m-1 d-1 and 5mg C m-3. d-1 during winter. With a short time lag, DOM concentrations followed the fluctuation in Chi a.
Sediment oxygen demand measurements revealed a mean mineralization rate of about 260 mg C m-2 d-1 during summer and 100–200 mg C m-2 d-1 in winter. Sediment bacterial density varied between 108 - 109 cells g (sediment dry wt)-1 in the top 5 cm sediment layer or, in terms of biomass, 4.3 g C m-l during summer and 0.6 g C m-2 during winter. Highest concentrations of DOM in pore waters were measured in September, coinciding with high rates of sediment oxygen demand. 相似文献
Sediment oxygen demand measurements revealed a mean mineralization rate of about 260 mg C m
7.
Daniele Nizzoli Giuseppe Castaldelli Marco Bartoli David Thomas Welsh Patricia Arriaga Gomez Anna Elisa Fano Pierluigi Viaroli 《Marine Ecology》2002,23(S1):297-306
Abstract. Dark respiration rates, dissolved inorganic nitrogen (DIN) fluxes and nitrification rates were measured at two sites in the microtidal Sacca di Goro lagoon in September 2000. DIN fluxes correlated with the biomass of the dominant macrofauna species (the amphipod Corophium spp. at station Giralda and the polychaete Neanthes spp. at station Faro). Respiration (> 6 mmol O2 m−2 h−1 ) and ammonium fluxes (> 80μmol N m−2 h−1 ) were higher at station Giralda despite the lower organic matter content (4.5 %) and lower macrofauna biomass (4 g AFDW m−2 ). At both sites ammonium fluxes were significantly correlated with the biomass of the benthic infauna, but Corophium stimulated ammonium NH4 + fluxes 3-fold compared to Neanthes. The amphipod also enhanced nitrification rates (> 300 μmol N m−2 h−1 ) due to the high density of its burrows, the higher NH4 + regeneration rates and the enhanced oxygen supply to the bacteria. 相似文献
8.
Abstract. In the water-column of the Gulf of Trieste (Northern Adriatic Sea) flocculent, amorphous aggregates known as marine snow reach maximum density and dimensions up to 20cm in diameter during summer months. Sampling of these fragile macro-aggregates was carried out by SCUBA-divers.
A large detrital component was found to be embedded in an organic matrix together with a large array of intact phytoplankton species. Heterotrophic bacterial density ranged from 2–65 × 108 cells-g-1 (marine snow dry wt) and is therefore of the same order of magnitude as in the surface layer of the sediments of the Gulf. In terms of biomass, bacteria reached only 30–95% of heterotrophic microflagellates.
A mean abundance of marine snow of 5g (marine snow dry wt) m-3 was obtained for the water-column above the pyenolinc. At this boundary layer, however, a mean abundance of about 10g (marine snow dry wt) m-3 led to the formation of a distinct, 10-50cm thick layer. Based on these data and sedimentation rates of marine snow to the pyenoclinc (38 g [marine snow dry wt] m-2 d-1 ) the potential ecological significance of these macro-aggregates for the pelagic system of the Gulf of Trieste is discussed. 相似文献
A large detrital component was found to be embedded in an organic matrix together with a large array of intact phytoplankton species. Heterotrophic bacterial density ranged from 2–65 × 10
A mean abundance of marine snow of 5g (marine snow dry wt) m
9.
Abstract. Thirteen sampling cruises were conducted at weekly intervals in the inner part of the Gulf of Naples in the summer of 1983 to investigate the effects of excess nutrient inputs on phytoplankton communities. High surface phytoplankton concentrations (up to 1.15 ×108 cells 1-1 ) were recorded, particularly near Naples harbour and along the eastern coast, two locations that receive most of the area's sewage and industrial discharge. Phytoplankton populations were generally dominated by small species, mainly diatoms, which were associated with small phytoflagcllatcs. Species diversity values were relatively high (H'≤ 3.62) in most samples. Throughout the sampling period a high spatial and temporal variability for phytoplankton abundances and species composition was observed. 相似文献
10.
珠江口异养细菌时空分布特征及其调控机制 总被引：2，自引：0，他引：2
河口是海陆相互作用的重要地带, 往往呈现出独特的生物地球化学过程, 是研究碳循环过程的重要场所。在春季(2015年5月)、夏季(2015年8月)和冬季(2016年1月)分别对珠江口海域异养附生细菌和游离细菌时空分布及其各自高核酸(HNA)、低核酸(LNA)类群的相对贡献进行了调查研究, 并对其调控因子进行了相应探讨。结果表明, 珠江口异养细菌分布具有明显的时空差异。空间分布上, 珠江口异养细菌丰度自河口上游至下游呈递减趋势, 主要与上游污水输入以及珠江径流与高盐外海水在河口内的混合有关; 在雨季, 河口中下游盐度锋面区出现异养细菌丰度和叶绿素a质量浓度的高值区, 锋面区使营养物质停留时间增加, 促进浮游生物生长。垂直方向上, 表层异养细菌丰度略高于底层。时间尺度上, 异养细菌总丰度在春季最高(表层均值为2.94±1.23×109个 •L-1, 底层为2.81±1.50×109个 •L-1), 夏季次之(表层均值为2.32±0.43×109个 •L-1, 底层为1.90±0.50×109个 •L-1), 冬季最低(表层均值为1.06±0.33×109个 •L-1, 底层为9.76± 3.44×108个 •L-1)。珠江口海域异养细菌以附生细菌为主, 占异养细菌总丰度的16.56%~96.19%, 整体分布较稳定, 冬季最高(平均78.65%)、夏季(70.32%)与春季相近(68.17%)。附生细菌以代谢活跃的HNA类群为主, 游离细菌则主要以LNA类群为主, 代谢活性整体相对较低。 相似文献
11.
Microbial Biomass Dynamics Along a Trophic Gradient at the Atlantic Barrier Reef off Belize (Central America) 总被引：2，自引：0，他引：2
Abstract. Recent findings indicate that heterotrophic bacteria and not phytoplankton are the most numerous biomass components even in the euphotic zone of oligotrophic, open oceans. In this study it was hypothesized that the microbial biomass components change within a few hundred meters as oligotrophic water flows across the reef and becomes enriched with nutrients. Along a trophic gradient, four stations at the Atlantic Barrier Reef off Belize (Central America) were sampled for microbial biomass components. Phytoplankton biomass (measured as chlorophyll a) ranged from the most oligotrophic station (St. 1) to the most eutrophic station (St. 4) from 6.9–415.5 μg CI"' (assuming a C:chl a ratio of 30): heterotrophic bacterial biomass increased 4-fold (from 10.1–46.4μg C 1-1 ), heterotrophic nanoflagellate (HNAN) biomass increased from 4.6-19ug C 1-1 , and cyanobacteria from 0.9-4.5 μg C-1-1 . Production estimates derived from seawater cultures revealed a 5-fold increase in bacterial production from the oligotrophic station (3.7 ug C 1-1 d-1 ) to the eutrophic St. 4 (17.8ug C-1-d1-1 )- Cyanobacterial production rose from 1.1–3.5ug C-1–d-1 and HNAN production from 0.65-1.13 μg C-1-1 -d-1 . While cyanobacteria contributed between 13 and 20% to the autotrophic plankton component in the oligotrophic waters, their contribution dropped to about 1 % at the eutrophic stations. 相似文献
12.
Abstract. Coastal Patagonian sea waters had been differentially nutrient-enriched to determine (i) the magnitude of the algal biomass supported and (ii) which species were able to best compete for the available nutrients. Nitrogen was found to be the nutrient limiting growth of the natural phytoplankton population. The addition of NO3 at 25 μg at 1-1 led to a 10 to 30 μg 1-1 increase in chlorophyll a in all but those treatments containing trace metal additions. The best yield coefficients were obtained when a chelator (EDTA) was added with NO3 . A pool of nine diatom species were common in the N03 supplemented waters and the addition of vitamins along with NO3 allowed two of the nine species to dominate. 相似文献
13.
The use of taxonomic distinctness indices in assessing patterns of biodiversity in modular organisms 总被引：1，自引：0，他引：1
Stanislao Bevilacqua Simonetta Fraschetti Antonio Terlizzi & Ferdinando Boero 《Marine Ecology》2009,30(2):151-163
Estimating diversity of modular organisms may be problematic due to actual difficulties in discriminating between 'individuals' and quantifying their abundances. Quantitative data, when available, are collected through methods that could preclude the application of classical diversity indices, making comparisons among studies difficult. Taxonomic distinctness indices, such as the 'Average Taxonomic Distinctness' (Δ+ ) and the 'Variation in Taxonomic Distinctness' (Λ+ ) may represent suitable tools in investigating diversity beyond the simple species number. The potential usefulness of such indices has been explored almost exclusively on unitary organisms, neglecting modular ones. In this study, we employed Δ+ and Λ+ to analyse patterns of diversity of epiphytic hydroid assemblages living on Cystoseira seaweeds at a hierarchy of spatial scales, along 800 km of rocky coast (SE Italy). ANOVA on species richness and Λ+ showed no significant difference in sample diversity at the investigated spatial scales. In contrast, there were significant differences at the scale of 10s of km in Δ+ . Analyses based on simulations detected significant variations at all spatial scales in Δ+ . Such findings underline the potential of Δ+ in highlighting relevant spatial scales of variation in patterns of hydroid diversity. Our results also suggest that the interplay between natural environmental variations and the complex ecological traits of modular organisms might affect taxonomic distinctness indices. We stress the need for further investigations focusing on modular organisms before any generalizations on the use of taxonomic relatedness measures in examining marine biodiversity can be made. 相似文献
14.
2012年夏季南海西北部网采浮游植物群落结构 总被引：2，自引：0，他引：2
根据2012年8—9月在南海西北部海区的采样调查,对网采浮游植物的群落结构进行了研究。本次调查共检出浮游植物206种(包括变种及变形),隶属于4门55属,其中硅藻门40属114种,占总种数的55.3%;甲藻门10属86种,占总种数的41.7%。浮游植物平均细胞丰度为66.67×104cells·m-3,硅藻平均细胞丰度为65.79×104cells·m-3,甲藻平均细胞丰度为0.88×104cells·m-3。优势种为伏氏海线藻 Thalassionema franenfeldii、翼根管藻 Rhizosolenia alata和菱形海线藻 Halassionema nizschioides。调查海区的Shannon-Weiner多样性指数(H′)平均值为2.67,高值区位于西沙群岛和调查区东部。对比分析浮游植物细胞丰度与环境因子可知,浮游植物细胞丰度高和种类多的区域,其水体营养盐含量也高,说明营养物质与该区浮游植物细胞丰度分布和群落结构密切相关。 相似文献
15.
2017年8月对大亚湾海域浮游群落初级生产、群落呼吸代谢及其平衡特征进行了研究, 并分析了其潜在环境影响因素以及对沿岸生态系统功能与健康的指示作用。研究结果表明, 大亚湾夏季海水表层呈自养状态, 而底层呈异养状态, 群落总初级生产力(gross primary productivity, GPP)、呼吸代谢速率(community respiration, CR)与净生产力(net commutnitiy production, NCP)在表层分别为1335.36±910.12、597.86±403.30和737.50±608.22mg C·m-3·d-1; 在底层分别为43.65±37.05、216.25±147.28和-160.27±137.01mg C·m-3·d-1。海湾整体呈自养状态, 水柱平均NCP为233.41±248.88mg C·m-3·d-1; 部分沿岸水域存在异养状态。1~200μm粒级浮游生物是GPP和CR的主要贡献者。相关性分析和主成分分析显示, NCP在表层受GPP和CR共同调控, 且与浮游植物生物量和营养盐正相关; 而在底层主要受CR影响, 且与盐度正相关。大亚湾夏季群落生产代谢平衡存在明显的水平和垂向变化, NCP的区域差异与潜在波动性对该海湾生态系统稳定性及健康状况有重要的指示作用。 相似文献
16.
Antonella Penna Maria Grazia Giacobbe Nunzio Penna Francesca Andreoni Mauro Magnani 《Marine Ecology》2002,23(S1):320-328
Abstract. High-biomass blooms of A. taylori Balech have recently been spreading over new Mediterranean areas, with evident adverse effects on the marine ecosystem. In 1999–2000, a new Mediterranean locality was affected by blooms of A. taylori: the West Bay of Vulcano (Aeolian Islands, Tyrrhenian Sea), with maximum cell densities of 1.2 × 107 cells 1−1 in August 1999 and 4.0 × 106 cells 1−1 in August 2000 observed together with yellowish water discoloration. The seawater samples contained high concentrations of nutrients as DIN (Dissolved Inorganic Nitrogen), especially NH3 -N with values of 14.4 μM and TOT-P (Total Phosphorus) with values of 3.2 μM due to the anthropic presence and discharge of untreated sewage. The climatic conditions also seem to influence the occurrence and spreading of the A. taylori blooms in the Vulcano Bay. Clonal cultures of A. taylori , established from Italian and Spanish seawater samples, were used for the sequence analyses of the 5.8S rDNA gene and ITS regions in order to study the genetic variability of different geographical populations of Alexandrium species in the Mediterranean area and to further develop the molecular markers for HAB key-species. 相似文献
17.
Dispersal of Benthic Meiofauna by Wave and Current Action in Bogue Sound, North Carolina, USA 总被引：3，自引：0，他引：3
Abstract. Results from sediment trap experiments in Bogue Sound, North Carolina, indicate that meiofauna from a wide variety of taxa and benthic habitats are regularly suspended in the subtidal water column. Interstitial species are estimated to account for 10–30 % of the suspended meiofauna. Measurements of suspended nematode concentrations, when compared with wind and current velocity records, suggest that in Bogue Sound, shoaling and breaking waves are more important than tidal currents in controlling meiofauna erosion and deposition. Linear regression analysis indicates that 80% (r = 0.907) of the variation in suspended nematode density is correlated with changes in the mean onshore-offshore component of local wind velocity. Nematode turnover associated with spring and summer coastal wind patterns is estimated to be several hundred animals per m2 per day. Once suspended, meiofauna may be carried up to 10 km per day by residual currents in the Sound. Although erosion, transport and deposition of benthic nematodes by wave and current action appears to provide an effective means of dispersal along continental coastlines, the high settling velocity of nematodes suspended in Bogue Sound (on the order of 10-4 m s-1 ) suggests that net downward flux in shelf and slope waters probably prevents their dispersal across ocean basins by surface currents. 相似文献
18.
Response of Summer Phytoplankton to Episodic Meteorological Events (Gulf of Trieste, Adriatic Sea) 总被引：2，自引：0，他引：2
Abstract. Despite increasing evidence that atmospheric deposition may contribute considerably to new production in coastal seas, the role of this nutrient source in the shallow northern Adriatic ecosystem has remained largely unassessed. This study demonstrates that locally collected rain water significantly stimulates primary production and phytoplankton biomass accumulation in microcosm experiments. The concentration of nutrients in rain water collected during summer storms (11.38–77.19 μmol·1-1 nitrate. 4.45–36.38 μmol.1·1 ammonium, 0.93–4.75 μmol·1-1 phosphate) indicated that the precipitation is influenced by anthropogenic emissions from urbanised and industrialised regions of the European continent. Rainfall events delivered relatively large (127 tons nitrogen, 9.5 tons phosphorus in the period 10 June to 10 September, 1993). though episodic, nutrient input into the area. Field measurements showed that storm events were followed by an increase of phytoplankton standing crop and a shift of community structure. 相似文献
19.
深入研究珠江口地区海陆过渡带壳内低速层的结构和构造特征对于理解板内地震的发震机理、孕震构造及该区域的地壳结构具有重要的地质地球物理意义。利用2015年珠江口区域海陆地震联测L2-ME测线上的19个地震台站(包括陆上台站14台, 海底地震仪5台)记录到的地震数据来探明该区域低速层的结构和构造特征。在常规震相的基础上, 加入了大量的滑行波震相(Ph)进行结构模型计算, Ph震相的增加使得地壳内部10~20km范围内的射线覆盖密度有了显著提高, 从而获得了L2-ME测线下方更为精确的地壳纵波速度结构模型。结果发现, 模型中测线下方13~18km深度范围内稳定连续展布的壳内低速层被清晰成像, 其内部速度稳定在5.7~6.0 km·s-1之间, 与上下层界面速度差分别为0.5km·s-1、0.4km·s-1, 低速特征明显。该低速层厚度由陆侧的3.5km左右降至海侧的1km, 呈现出向海侧逐渐减薄的趋势, 低速层底界面起伏变化较大且具有与莫霍面相似的起伏特征。 相似文献
20.
Stock Evaluation of Three Littoral Echinoid Species on the Catalan Coast North-Western Mediterranean 总被引：2，自引：0，他引：2
Cruz Palacín Xavier Turon Manuel Ballesteros Gonzalo Giribet Salvador López 《Marine Ecology》1998,19(3):163-177
Abstract. We estimated the abundances of the three common littoral echinoid species Paracentrotus lividus, Arbacia lixula and Sphaerechinus granularis in a littoral zone between 0 and 10m depth on the Catalan shores NE Spain. Densities of each species were estimated from a total number of 11 571× 1 m2 sampling units deployed at 152 sites along the 13 zones into which the coast was divided. The surface area available in each of these zones was estimated at the scale of the sampling unit 1 m2 taking into account the fractal dimension of the shore. The stocks individuals > 2cm test diameter of these species for the whole Catalan shore ≅ 300 km, straight-line distance were estimated to be about 279.1 × 106 individuals for P. lividus , 28.9 × 106 individuals for A. lixula and 10.9 × 106 individuals for S. granularis. These sea-urchins are key species in the regulation of algal communities and some of them P. lividus. S. granularis are of commercial interest. This information will provide a tool for the future monitoring and management of this resource, which now faces diverse pressures of human origin. 相似文献