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Consideration of soil quality indicators is fundamental for understanding and managing ecosystems. Despite the evidence regarding the importance of soil for provision of local and global ecosystem services, such as water regulation and carbon sequestration, soil remains an under‐investigated and undermined aspect of the environment. Here we evaluate to what extent soil indicators are taken into account in restoration. We focused on the Brazilian Atlantic Forest, a highly fragmented biome and a global biodiversity hotspot. We conducted a systematic literature review and we showed that the majority (59%) of the studies on restoration did not consider any soil indicator. Studies that demonstrated the importance of soil indicators most commonly reported soil pH (71%, n = 44), followed by potassium content (66%, n = 41) and phosphorus (64.5%, n = 40), while the least reported indicator was water retention (6.5%, n = 4). Only 40% of the retrieved studies included information about reference sites or project baseline information. We complement our literature review with a case study on restoration in two areas of the Atlantic Forest. We found a relation between soil indicators such as soil organic matter, nitrogen, sodium and sand content, and aboveground indicators, confirming a necessity to include soil screening in restoration. Moreover, we found that prior to restoration none of these soil indicators were analyzed. This study highlights the gap that exists in soil data in restoration in studies on the Brazilian Atlantic Forest. We urge scientists and practitioners to include basic soil analysis to maximize the successful outcomes of restoration.  相似文献   

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The biodiversity loss, due to anthropic activities, has generated the necessity of studies that enable the ecosystem conservation. Nevertheless, the majority of studies restrict themselves to the floristic composition and phytosociological structure from determined pre-established diameter, neglecting attributes of the species, such as its (their) niche (s) of occurrence in the forest, thus, making it difficult to identify potential species for restoration. In this way, the present study aimed to evaluate the structure of a forest fragment in the extreme South of Atlantic Forest Biome, through identification of species in the different layers. There were used 18 parcels of 10 m × 20 m, distributed systematically, where the vegetation was evaluated in four size classes. The characterization of the structure of the arboreal-shrub of the forest was performed by the data comparison of the floristic composition and phytosociological structure. In the fragment of forest studied, there were sampled a total of 2.176 individuals. The floristic composition of the area includes 74 species, belonging to 58 genera and 28 botanical families. We observed differences in relation of richness and diversity of species among the analyzed layers, the intermediate layer presented the lowest richness of species, being the pioneers and initial secondaries the least representatives. Trichilia claussenii, Sorocea bonplandii, Actinostemon concolor, Apuleia leiocarpa and Nectandra megapotamica were the most abundant species and well distributed in the different size classes, and they can be used in the enrichment of areas in process of restoration in the scope of the Deciduous Seasonal Forest in the extreme South of Atlantic Forest Biome. Ocotea puberula, Allophylus edulis, Cedrela fissillis and Machaerium paraguariense formed a group of species with expressive representativeness in the arboreal layer, thus they can be used in the moment of planting as species to the fast covering of the area.  相似文献   

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Recent studies suggest very low survival of seedlings planted in streamside areas containing thick (>1 m) deposits of legacy alluvial sediments. We planted 2,450 seedlings representing eight species in a streamside area with thick legacy sediments and monitored them for 5 years. The overall survival of approximately 60% (range across species: approximately 38–74%) was surprisingly high and mean overall growth per seedling (approximately 3.27 m) was very good, ranging between 2.5 and 4.7 m depending on tree species. Although both seedling survival and growth exhibited significant spatial variation, none of the results supports the idea that legacy sediment thickness up to 1.5 m is an important factor with regard to success of streamside reforestation. For survival, soil depth was significant for the sediment accretion zone but not the legacy sediment zone. For growth, the response was significant and positive, with the eight species on average growing significantly better as legacy sediment increased in thickness. The results suggest that the presence of legacy sediment up to 1.5 m thick should not preclude the successful restoration of natural forest along stream channels in the eastern Piedmont of North America. Finally, the study suggests that the U.S. federal criteria for reforestation success (i.e. 222 stems per hectare after 5 years) can still be met on legacy sediment sites by increasing the planting density approximately 25% from the required minimum of 296 stems per hectare to 370.  相似文献   

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Mullen JR  Das M  Brill SJ 《Genetics》2011,187(1):73-87
Saccharomyces cerevisiae cells lacking the Slx5-Slx8 SUMO-targeted Ub ligase display increased levels of sumoylated and polysumoylated proteins, and they are inviable in the absence of the Sgs1 DNA helicase. One explanation for this inviability is that one or more sumoylated proteins accumulate to toxic levels in sgs1Δ slx5Δ cells. To address this possibility, we isolated a second-site suppressor of sgs1Δ slx5Δ synthetic lethality and identified it as an allele of the ULP2 SUMO isopeptidase. The suppressor, ulp2-D623H, behaved like the ulp2Δ allele in its sensitivity to heat, DNA replication stress, and DNA damage. Surprisingly, deletion of ULP2, which is known to promote the accumulation of poly-SUMO chains, suppressed sgs1Δ slx5Δ synthetic lethality and the slx5Δ sporulation defect. Further, ulp2Δ's growth sensitivities were found to be suppressed in ulp2Δ slx5Δ double mutants. This mutual suppression indicates that SLX5-SLX8 and ULP2 interact antagonistically. However, the suppressed strain sgs1Δ slx5Δ ulp2-D623H displayed even higher levels of sumoylated proteins than the corresponding double mutants. Thus, sgs1Δ slx5Δ synthetic lethality cannot be due simply to high levels of bulk sumoylated proteins. We speculate that the loss of ULP2 suppresses the toxicity of the sumoylated proteins that accumulate in slx5Δ-slx8Δ cells by permitting the extension of poly-SUMO chains on specific target proteins. This additional modification might attenuate the activity of the target proteins or channel them into alternative pathways for proteolytic degradation. In support of this latter possibility we find that the WSS1 isopeptidase is required for suppression by ulp2Δ.  相似文献   

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景观生态恢复与重建是区域生态安全格局构建的关键途径   总被引:74,自引:8,他引:74  
生态恢复与重建是跨尺度、多等级的问题,其主要表现层次应是生态系统(生物群落)、景观,甚至区域,而不能仅仅局限于生态系统。景观的恢复与重建是针对景观退化而言,景观退化从表现形式上可分为景观结构退化与景观功能退化。景观结构退化即景观破碎化,是指景观中各生态系统之间的各种功能联系断裂或连接度(connectivity)减少的现象;而鲜受重视的景观聚集(aggregation)在很多情况下同样具有造成景观退化的负面效应。景观功能退化是指与前一状态相比,由于景观异质性的改变导致景观的稳定性与服务功能等的衰退现象。景观恢复是指恢复原生生态系统间被人类活动终止或破坏的相互联系;景观生态建设应以景观单元空间结构的调整和重新构建为基本手段,包括调整原有的景观格局,引进新的景观组分等,以改善受胁或受损生态系统的功能,提高其基本生产力和稳定性,将人类活动对于景观演化的影响导入良性循环。二者的综合,统称为景观生态恢复与重建,是构建安全的区域生态格局的关键途径。其目标是建立一种由结构合理、功能高效、关系协调的模式生态系统(model ecosystem)组成的模式景观(model landscape),以实现生态系统健康、生态格局安全和景观服务功能持续,以3S(RS,GPS,GIS)技术为支撑的GAP(ageographic approach to protect biological diversity)分析将为大尺度景观恢复的诊断、评价、规划提供重要的手段。景观中某些关键性点、位置或关系的破坏对整个生态安全具有毁灭性的后果,研究景观层次上的生态恢复模式及恢复技术、选择恢复的关键位置、构筑生态安全格局已成为景观生态学家关注的焦点。  相似文献   

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The signaling hypothesis of eggshell coloration in birds isbased on the assumption that females of species with blue-greeneggs signal their phenotypic quality to their mates throughdeposition of the antioxidant biliverdin as pigment. Egg pigmentationmay be an expression of the condition of females at laying orof genetic linkages between egg color and female performancevariables. We have supplemented 16 pied flycatcher, Ficedulahypoleuca, females with mealworms before and during laying andcompared the mass and color of their eggs as measured on theday of laying to those of 16 control females with the same nestconstruction and laying dates and clutch sizes. Supplementedfemales laid significantly heavier and more intensely blue-greeneggs than control females. Egg blue-green chroma was significantlyassociated with the amount of biliverdin in eggshells. Egg color,and thus biliverdin content, is an expression of female conditionat laying.  相似文献   

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Biodiversity and Conservation - Numerous conservation activities in Africa have been of little effect. In this study, we investigate socio-economic trade-offs that might have been overlooked, yet...  相似文献   

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Forest ecosystem restoration due to a national conservation plan in China   总被引:1,自引:0,他引:1  
China has a long history of large-scale deforestation that has contributed to serious consequences such as frequent geological disaster, flood and soil erosion. It was only recently that forest management strategy shifted from the traditional harvesting orientation to a more balanced forest ecosystem management approach with a focus on conservation. To understand the effects of such a shift, on the forest dynamics especially since the implementation of Natural Forest protection Project (NFPP), this paper examined the case of Lushuihe region, a typical region of the northeast China forest zone. Land use and landscape pattern for the period of 1975-2007 were analyzed based on Landsat MSS and TM images. Net primary, productivity (NPP), estimated with the CASA productivity model, was used to assess the human impacts on the forest ecosystem function. The results showed a reversing trend of forest cover since 1988, from continuous decrease to rather rapid increase. From 1975 to 1988, due to reckless deforestation, the forest cover in the case region decreased about 10439.39 ha (8.54% of the study area). Forest cover of the region recovered from 77.68% in 1988 to 89.56% in 1999 and 92.33% in 2007. While the forest cover increased, landscape metrics indicate that human disturbance significantly altered the composition and structure of the forest landscape. NPP change indicated a continued decreasing trend until 2007, albeit at a slower pace since 1988. In 2007, while the decreasing trend of NPP was reversed, the forest structure was still inferior to that of 1975. Looking forward, diversifying and securing the livelihoods of the still growing local population that have been heavily dependent on the traditional forestry industry remain one of the key challenges as well as solutions for enhancing and managing the regional forest ecosystem structure and function in the region.  相似文献   

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The objective of this work was to obtain an overview of studies on ecological restoration carried out in Argentina to date. By means of the Scopus database, we performed two literature searches, one in Spanish (restau* and Argentina) and the other in English (restor* and Argentina). Between 1996 and 2013, 105 publications were registered, representing 2% of publications in Biology and Ecology. Most of these appeared in international journals (87%), in English (86%), and 28% were coauthored with researchers from other countries, favoring visibility at an international level. We observed an increase in the number of studies per year over time, with a significant increase beginning in 2008. Of the 18 ecological regions in Argentina, we found studies relating to 12 as well as four studies relating to restoration in urban areas. This review of the literature is intended to increase awareness of restoration in Argentina and help identify current gaps relating either to this subject or to specific ecological regions.  相似文献   

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Background  

MixtureTree v1.0 is a Linux based program (written in C++) which implements an algorithm based on mixture models for reconstructing phylogeny from binary sequence data, such as single-nucleotide polymorphisms (SNPs). In addition to the mixture algorithm with three different optimization options, the program also implements a bootstrap procedure with majority-rule consensus.  相似文献   

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Although a previous genetic mixed-stock analysis (gMSA) conducted in the early 1990s showed that marine-captured New York Bight Atlantic sturgeon Acipenser oxyrinchus oxyrinchus almost exclusively originated from the Hudson River, fish from southern U.S. rivers were well represented within this contemporary sample (n = 364 fish), at least during the autumn. Widely distributed spawning stocks are therefore exposed to heavy fishing activity and habitat degradation in this relatively small area, illustrating the need for spatial management across multiple management jurisdictions and routine gMSA to account for temporal change.  相似文献   

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Forest succession was studied in four plots in former grasslands at the Ngogo study area in Kibale National Park, Uganda. The plots were located in areas that had been protected from fire for 0.58, 25, 9 and ≈30 years for plots 1, 2, 3 and 4, respectively. Species richness reflected the length of time that the plot had been protected from fire; it was highest in plot 4 and lowest in plot 1. Species density, stem density and basal area were all highest in plot 4 and lowest in plot 1. The species densities of plots 2 and 3 were not different. Similarly, plots 2 and 4 did not differ with regard to stem density or basal area. Animal seed dispersers played a vital role in the colonization of grasslands by forest tree species.  相似文献   

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