长江中下游滩地造林技术     

吴彦亮 《北京农业》2012,(15):153-154

长江中下游滩地是特殊的造林地,造林地整理要加强沥水,选择耐水湿且耐旱树种,中至大密度冬季造林,可采取多种产业复合经营的模式,加强管理,能获得较好效益。  相似文献   

江河滩地多功能用材林经营技术研究   总被引：2，自引：0，他引：2  

袁位高  江波  戚连忠  朱锦茹  吴发荣  申屠福军 《浙江林业科技》2003,23(2):1-6

通过滩地多功能用材林的树种选择、配置原则、配置方式、经营模式、采伐更新技术及其它相关经营技术等试验研究，集中分析了主要滩地树种的耐水性及选择原则，提出了长短轮伐周期结合、主导功能优先等配置原则和阶梯式带状混交、松阔复层混交等8种配置方式；总结出林—农、林一游等6种经营模式；在对不同采伐方式、采伐强度、采伐作业技术的比较研究基础上，提出了生态约束下的采伐更新技术。  相似文献   

黄河下游放淤改土固堤技术分析   总被引：2，自引：1，他引：1  

赵世来  刘桂珍  夏富洲  赵洪林 《中国农村水利水电》2001,8(7):26-28

根据黄河下游滩区放淤改土固堤的实践，对淤临河洼地、淤滩改土、淤村塘洼地、淤串沟等淤类型进行了分析，提出了放淤改土固堤进水口门、输水渠、围堤、退排水工程布置和引水量、放淤量的计算方法。  相似文献   

Public Perception and Understanding of Shark Attack Mitigation Measures in Australia     

Roxanne Crossley  C. Matilda Collins  Stephen G. Sutton 《Human Dimensions of Wildlife》2014,19(2):154-165

Human–wildlife conflict (HWC) is a significant and growing problem, with mitigation measures being increasingly dependent on sociopolitical landscapes. We surveyed 766 people from two Australian states to assess their understanding of shark attack mitigation measures. Although beach users were relatively aware of existing mitigation measures, the efficacy of aerial patrol was overestimated, as was the risk of shark attack. The latter, as well as the innate fear of shark attacks, is likely to explain the high level of worry related with shark attack and fits within the affect heuristic that can influence how people respond to risk situations. Beach users did not, however, choose beaches based on existing mitigation measures. Results highlight the need for improved education about the risks of shark attack and for further research into the emotional response from low probability–high consequences incidents.  相似文献   

围垦低洼滩涂合理利用模式的经济学研究     

谢雷宁  夏文才 《浙江大学学报(农业与生命科学版)》1991,(4)

采用单位土地产出率、平均收益率和内部报酬率等几种方法,对假设的围垦滩涂地区两种不同的农业利用方式进行了较为详细的比较,并对比较得出的结论,进行了多因子的不肯定性预测、分析。  相似文献   

11个造林树种在京北荒滩应用固体水效果比较研究     

李一为  周心澄  张启生  汪明 《西北林学院学报》2007,22(2):91-93

以往研究表明,固体水能够提高造林成活率,特别在困难立地造林应用中已取得较好效果。为进一步选择应用固体水效果较好的树种,为今后困难立地造林树种选择提供参考,于2004年4月在北京市延庆县龙庆峡荒滩进行固体水多树种造林应用试验。通过分析树种成活率和相关生长指标,对比研究固体水多树种应用效果。结果表明,在荒滩造林绿化中,固体水能够提高各供试树种成活率和生长指标;银杏、旱柳、国槐、新疆杨、白榆、侧柏、刺槐、毛白杨和樟子松等9个树种应用固体水效果较好。  相似文献   

江苏海涂土壤盐分地球化学特征的初步研究   总被引：2，自引：0，他引：2  

方明  陈邦本  胡蓉卿 《土壤学报》1992,29(2):208-210

根据江苏海涂地区所做的大量分析数据,应用数理统计方法,对滨海盐土的盐分地球化学类型及其变化规律进行了定量的研究,分别提出盐分离子组成规律和盐分变化中几种离子当量比的特征值,为滨海盐土的分类和利用改良提出了依据。  相似文献   

Feeding ecology of dominant demersal fish species <Emphasis Type="Italic">Favonigobius gymnauchen,Repomucenus</Emphasis> spp. and <Emphasis Type="Italic">Tarphops oligolepis</Emphasis> at a sandy beach where larval Japanese flounder settle in the Seto Inland Sea,Japan     

Masayuki?YamamotoEmail author  Osamu?Tominaga 《Fisheries Science》2005,71(6):1332-1340

ABSTRACT:   Feeding habits of Favonigobius gymnauchen , Repomucenus spp. and Tarphops oligolepis were examined during the period from May to August in 1999, 2000 and 2001 at a sandy beach in the central Seto Inland Sea, Japan. The three species of fish accounted for more than 60% of all fish collected in terms of number of individuals. All three species mainly consumed small crustaceans. However, the major prey of F .  gymnauchen and Repomucenus spp. differed from that of T .  oligolepis . F .  gymnauchen and Repomucenus spp. mainly consumed mysids and small crangonid shrimp (<12 mm in body length), which predominated in the study area. T .  oligolepis actively selected only epifaunal mysids Nipponomysis ornata and avoided crangonid shrimp and gammarids . The frequencies of occurrence of fish in the guts of the three dominant species were very low, and larval and juvenile Japanese flounder were not observed in any of the three fish species. The diet of juvenile Japanese flounder was similar to that of the three species. From these results, it appears that these three fish are competing species for the flounder.  相似文献   

Daily rations and food availability of Japanese flounder Paralichthys olivaceus,small flounder Tarphops oligolepis and sand goby Favonigobius gymnauchen at a sandy beach in the central Seto Inland Sea,Japan     

Yamamoto  Masayuki  Tominaga  Osamu 《Fisheries Science》2007,73(2):314-323

ABSTRACT:     To estimate the daily rations of Paralichthys olivaceus , Tarphops oligolepis and Favonigobius gymnauchen and to clarify diel variation in food availability to them, diel sampling was conducted over a 24-h period at a sandy beach in the Seto Inland Sea, Japan. The mean total length and body weight (BW) of P. olivaceus , T. oligolepis and F. gymnauchen were 32.6 mm (0.35 g), 23.7 mm (0.13 g) and 50.2 mm (1.03 g), respectively. The mean stomach contents index and percentages of stomachs with food were high during the day but low at night, indicating that these species are day-feeders. Paralichthys olivaceus and F. gymnauchen consumed mainly mysids and crangonids, whereas T. oligolepis fed chiefly on mysids. The estimated mean daily rations (95% confidence intervals) for P. olivaceus , T. oligolepis and F. gymnauchen made with the bootstrap method were 18.1 (9.3–31.3)%BW, 13.2 (7.9–24.3)%BW and 3.7 (1.7–7.4)%BW, respectively. Mysids were more abundant in the near-bottom layer during the day than at night, but the opposite was true for crangonids.  相似文献   

Spatio‐temporal distribution of sea turtle strandings and factors contributing to their mortality in south‐eastern Brazil     

Alicia Bertoloto Tagliolatto  Daphne Wrobel Goldberg  Matthew H. Godfrey  Cassiano Monteiro‐Neto 《水产资源保护:海洋与淡水生态系统》2020,30(2):331-350

1. Data on stranded sea turtles were examined between 2010 and 2016 along the northern region of Rio de Janeiro state and between 2016 and 2017 in the southern region, looking for spatio‐temporal patterns and determining which factors contributed to their mortality.
2. A total of 12,162 strandings of all five species that occur in Brazil were recorded, with Chelonia mydas being the most common (89.9%). Sea turtles use the Rio de Janeiro coast as a feeding and/or migration area. The intense upwelling (October to April) may be an important factor for the sea turtles feeding in this region, mainly for Eretmochelys imbricata and Dermochelys coriacea, which had a higher number of strandings during this period.
3. Areas further north of the study area include an important nesting site for Caretta caretta in Brazil, which explains the higher concentration of strandings of subadults/adults of this species in this region and during its nesting season.
4. Many anthropogenic threats to sea turtles were documented, mainly incidental capture in fisheries and marine debris, indicating possible hotspots for these threats in the regions of Sepetiba and Guanabara Bays, Cabo Frio, and São Francisco de Itabapoana.
5. Among the natural causes of strandings, the primary factors were chronic illness, endoparasites, and fibropapillomatosis. However, pollution may also be an indirect threat, which negatively affects these animals through reduced health and immunosuppression, leaving them more susceptible to opportunistic diseases.
6. These data are valuable for directing and implementing specific and local mitigation measures along the Rio de Janeiro state coast, such as avoiding bycatch hotspots through fleet communication programmes and/or area and seasonal closures, enforceable legislation, effective penalties and proper waste management.

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