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1.
This paper examines the relationship between protected and endangered riverine species (target species) and hydrodynamics in river-floodplain ecosystems, combining ecological and policy-legal aspects of biodiversity conservation in river management. The importance of different hydrodynamic conditions along a lateral gradient was quantified for various taxonomic groups. Our results show that (i) target species require ecotopes along the entire hydrodynamic gradient; (ii) different parts of the hydrodynamic gradient are important to different species, belonging to different taxonomic groups; (iii) in particular low-dynamic parts are important for many species and (iv) species differ in their specificity for hydrodynamic conditions. Many species of higher plants, fish and butterflies have a narrow range for hydrodynamics and many species of birds and mammals use ecotopes along the entire gradient. Even when focussing only on target species, the entire natural hydrodynamic gradient is important. This means that the riverine species assemblage as a whole can benefit from measures focussing on target species only. River reconstruction and management should aim at re-establishing the entire hydrodynamic gradient, increasing the spatial heterogeneity of hydrodynamic conditions.  相似文献   
2.
Drylands encompass over 40% of terrestrial ecosystems and face significant anthropogenic degradation causing a loss of ecosystem integrity, services, and deterioration of social‐ecological systems. To combat this degradation, some dryland restoration efforts have focused on the use of biological soil crusts (biocrusts): complex communities of cyanobacteria, algae, lichens, bryophytes, and other organisms living in association with the top millimeters of soil. Biocrusts are common in many ecosystems and especially drylands. They perform a suite of ecosystem functions: stabilizing soil surfaces to prevent erosion, contributing carbon through photosynthesis, fixing nitrogen, and mediating the hydrological cycle in drylands. Biocrusts have emerged as a potential tool in restoration; developing methods to implement effective biocrust restoration has the potential to return many ecosystem functions and services. Although culture‐based approaches have allowed researchers to learn about the biology, physiology, and cultivation of biocrusts, transferring this knowledge to field implementation has been more challenging. A large amount of research has amassed to improve our understanding of biocrust restoration, leaving us at an opportune time to learn from one another and to join approaches for maximum efficacy. The articles in this special issue improve the state of our current knowledge in biocrust restoration, highlighting efforts to effectively restore biocrusts through a variety of different ecosystems, across scales and utilizing a variety of lab and field methods. This collective work provides a useful resource for the scientific community as well as land managers.  相似文献   
3.
In regenerating coastal dune forest, the canopy consists almost exclusively of a single species, Acacia karroo. When these trees die, they create large canopy gaps. If this promotes the persistence of pioneer species to the detriment of other forest species, then the end goal of a restored coastal dune forest may be unobtainable. We wished to ascertain whether tree species composition and richness differed significantly between canopy gaps and intact canopy, and across a gradient of gap sizes. In three known‐age regenerating coastal dune forest sites, we measured 146 gaps, the species responsible for gap creation, the species most likely to reach the canopy and the composition of adults, seedlings and saplings. We paired each gap with an adjacent plot of the same area that was entirely under intact canopy and sampled in the same way. Most species (15 of 23) had higher abundance in canopy gaps. The probability of self‐replacement was low for A. karroo even in the largest gaps. Despite this predominance of shade‐intolerant species, regenerating dune forest appears to be in the first phase of succession with ‘forest pioneers’ replacing the dominant canopy species. The nature of these species should lead to successful regeneration of dune forest.  相似文献   
4.
Rehabilitation of stranded marine mammals elicits polarized attitudes: initially done alongside display collections, but release of rehabilitated animals has become more common. Justifications include animal welfare, management of beach use conflict, research, conservation, and public education. Rehabilitation cost and risks have been identified that vary in degree supported by data rather than perception. These include conflict with fisheries for resources, ignorance of recipient population ecology, poor understanding of long-term survival, support of the genetically not-so-fit, introduction of novel or antibiotic-resistant pathogens, harm to human health, and cost. Thus facilities must balance their welfare appeal against public education, habitat restoration, human impact reduction, and other conservation activities. Benefits to rehabilitating marine mammals are the opportunity to support the welfare of disabled animals and to publish good science and so advance our understanding of wild populations. In specific cases, the status of a population may make conservation the main reason for rehabilitation. These three reasons for rehabilitation lead to contrasting, and sometimes conflicting, management needs. We therefore outline a decision tree for rehabilitation managers using criteria for each management decision, based on welfare, logistics, conservation, research, and funding to define limits on the number of animals released to the wild.  相似文献   
5.
Restoration treatments, such as revegetation with seeding or invasive species removal, have been applied on U.S. public lands for decades. Temporal trends in these management actions have not been extensively summarized previously, particularly in the southwestern United States where invasive plant species, drought, and fire have altered dryland ecosystems. We assessed long‐term (1940–2010) trends in restoration using approximately 4,000 vegetation treatments conducted on Bureau of Land Management lands across the southwestern United States. We found that since 1940, the proportions of seeding and vegetation/soil manipulation (e.g. vegetation removal or plowing) treatments have declined, while the proportions of prescribed burn and invasive species treatments have increased. Treatments in pinyon‐juniper and big sagebrush communities declined in comparison to treatments in desert scrub, creosote bush, and riparian woodland communities. Restoration‐focused treatment objectives increased relative to resource extraction objectives. Species richness and proportion of native species used in seeding treatments also increased. Inflation‐adjusted costs per area rose 750% for vegetation/soil manipulation, 600% for seeding, and 400% for prescribed burn treatments in the decades from 1981 to 2010. Seeding treatments were implemented in warmer and drier years when compared to the climate conditions of the entire study period and warmer and wetter years relative to several years before and after the treatment. These results suggest that treatments over a 70‐year period on public lands in the southwestern United States are shifting toward restoration practices that are increasingly large, expensive, and related to fire and invasive species control.  相似文献   
6.
目的:探究血栓通配合康复训练对缺血性脑卒中(cerebral arterial thrombosis,CAT)恢复期患者肢体康复的疗效情况。方法:选取2011年3月-2013年3月我院收治的84例CAT患者按数字表法随机分为观察组和对照组,各42例。对照组单纯采用康复训练治疗,观察组在对照组康复训练的基础上服用血栓通配合治疗,分别观察治疗前、治疗后1个月、3个月、6个月的各项基本指标并对比研究。结果:两组患者治疗前和治疗1月后Barthel评分无明显差异(P0.05);观察组治疗后3、6个月Barthel评分显著高于对照组,差异有统计学意义(P0.05),两组患者治疗前和治疗1月后肢体Fugl-Meyer评分无明显差异(P0.05);观察组治疗后3、6个月肢体Fugl-Meyer评分显著高于对照组,差异有统计学意义(P0.05),且对照组出院时上肢依然未完全恢复。通过对对照组和观察组患者的生活质量评分比较,观察组生活质量的各项评分均明显高于对照组,两组比较差异有统计学意义(P0.05)。结论:对缺血性脑卒中恢复期患者采用血栓通药物配合适当的康复训练疗效较好,术后肢体恢复理想,值得作为治疗CAT的首选方法在临床上推广应用。  相似文献   
7.
Globally, river degradation has decimated freshwater fish populations. To help reverse this trend in a southeastern Australia river, we used multiple restoration actions, including reintroduction of instream woody habitat, riparian revegetation, removal of a weir hindering fish movement, fencing out livestock, and controlling riparian weeds. We monitored the responses of native fish at the segment scale (20 km) and reach scale (0.3 km) over 7 years to assess the effectiveness of the different restoration strategies. Two closely related species, Murray cod Maccullochella peeli and trout cod Maccullochella macquariensis, increased at the restored segment compared with the control segment. However, inherent differences between river segments and low sample size hampered assessment of the mechanisms responsible for segment‐scale changes in fish abundance. In contrast, at the reach scale, only M. peeli abundance significantly increased in reaches supplemented with wood. These differential responses by 2 closely related fish species likely reflect species‐specific responses to increased habitat availability and enhanced longitudinal connectivity when the weir improved passage around a fishway. Changes in M. peeli abundance in segments supplemented with and without wood suggest an increase in carrying capacity and not simply a redistribution of individuals within the segment, facilitated the observed expansion. Our findings confirm the need to consider individual fish species' habitat preferences carefully when designing restoration interventions. Further, species‐specific responses to restoration actions provide waterway managers with precise strategies to target fish species for recovery and the potential to predict fish outcomes based on ecological preferences.  相似文献   
8.
喀斯特槽谷区土地石漠化与综合治理技术研发   总被引:9,自引:0,他引:9  
深入揭示流域尺度水-土-生资源格局和研发因地制宜的水-土-生治理技术是"十三五"石漠化治理工程的主要瓶颈。国家重点研发计划——"喀斯特槽谷区土地石漠化过程及综合治理技术研发与示范"项目(2016YFC0502300)针对槽谷区特点,锁定两个关键科学问题和五个关键技术,从过程机理研究-技术研发-应用示范3个层面解剖区域水/土/生物资源分布格局与地质地貌之间的关系,阐明石漠化过程中的相关生态变化机理,因地制宜地研发水土资源高效利用、土壤地上/下流/漏失阻控与生态恢复技术;研发野生砧木及经济树种互作效应与优化配套技术,构建槽谷区可持续的生态系统和生态产业模式并示范推广,为区域生态改善和贫困问题解决提供科技支撑。  相似文献   
9.
介绍了北京地区野牛动物救护工作的发展历程和现状,野生动物救护种类和伤病情况.根据在工作中遇到的实际情况,提出了野生动物救护中存在的问题和不足,并从野生动物管理和救护技术两个方面提出了相关建议和解决措施.  相似文献   
10.
The effects of sewage sludge, used to improve fertility of replaced soil, on vegetation were studied in limestone quarry restoration. Plant community growing in the first stages after sludge application was surveyed in six quarries of NE Spain. Areas with a mixture of sewage sludge and residual soil were compared to areas where the application consisted only of residual soil (a mixture of previous top soil and mine spoils). Sewage sludge was hypothesized to increase total biomass and cover, modifying species composition and delaying the early successional recover of the community. The results showed that both biomass and plant cover increased because of sewage sludge addition. The floristic composition was dominated by ruderal species that did not show any dependence on sewage sludge application. Convergence on similarity between sludge and control plots was not detected along a 5‐year period. Although species richness was significantly lower in sludge plots, diversity and equitability indexes did not show differences between treatments. The results did not show differences in the proportion of non‐native species. The proportion of legumes was lower in sludge plots. These results show that the plant communities resulting from the addition of sewage sludge to the soil used in limestone quarry restoration have more biomass and cover, but less number of species, and they do not show a clear trend to converge to those areas restored only with non‐amended soil.  相似文献   
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