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Short rotation coppice (SRC) systems can play a role as feedstock for bioenergy supply contributing to EU energy and climate policy targets. A scenario depicting intensive arable crop cultivation in a homogeneous landscape (lacking habitat structures) was compared to a scenario including SRC cultivation on 20 % of arable land. A range of indicators was selected to assess the consequences of SRC on soil, water and biodiversity, using data from the Rating-SRC project (Sweden and Germany). The results of the assessment were presented using spider diagrams. Establishment and use of SRC for bioenergy has both positive and negative effects. The former include increased carbon sequestration and reduced GHG emissions as well as reduced soil erosion, groundwater nitrate and surface runoff. SRC can be used in phytoremediation and improves plant and breeding bird biodiversity (exceptions: grassland and arable land species) but should not be applied in dry areas or on soils high in toxic trace elements (exception: cadmium). The scenario-based analysis was found useful for studying the consequences of SRC cultivation at larger scales. Limitations of the approach are related to data requirements and compatibility and its restricted ability to cover spatial diversity and dynamic processes. The findings should not be generalised beyond the representativeness of the data used.  相似文献   

3.
Short rotation coppice (SRC) of willow and poplar might be a promising phytoremediation option since it uses fast growing, high biomass producing tree species with often a sufficient metal uptake. This study evaluates growth, metal uptake and extraction potentials of eight willow clones (Belders, Belgisch Rood, Christina, Inger, Jorr, Loden, Tora and Zwarte Driebast) on a metal-contaminated agricultural soil, with total cadmium (Cd) and zinc (Zn) concentrations of 6.5 ± 0.8 and 377 ± 69 mg kg?1 soil, respectively. Although, during the first cycle, on average generally low productivity levels (3.7 ton DM (dry matter) ha?1 y?1) were obtained on this sandy soil, certain clones exhibited quite acceptable productivity levels (e.g. Zwarte Driebast 12.5 ton DM ha?1 y?1). Even at low biomass productivity levels, SRC of willow showed promising removal potentials of 72 g Cd and 2.0 kg Zn ha?1 y?1, which is much higher than e.g. energy maize or rapeseed grown on the same soil. Cd and Zn removal can be increased by 40% if leaves are harvested as well. Nevertheless, nowadays the wood price remains the most critical factor in order to implement SRC as an acceptable, economically feasible alternative crop on metal-contaminated agricultural soils.  相似文献   

4.
Regularly managed electric power line corridors may provide habitats for both early-successional grassland plant species and disturbance-dependent alien plant species. These habitats are especially important in urban areas, where they can help conserve native grassland species and communities in urban greenspace. However, they can also provide further footholds for potentially invasive alien species that already characterize urban areas. In order to implement power line corridors into urban conservation, it is important to understand which environmental conditions in the corridors favor grassland species and which alien species. Likewise it is important to know whether similar environmental factors in the corridors control the species composition of the two groups. We conducted a vegetation study in a 43 kilometer long urban power line corridor network in south-western Finland, and used generalized linear models and distance-based redundancy analysis to determine which environmental factors best predict the occurrence and composition of grassland and alien plant species in the corridors. The results imply that old corridors on dry soils and steep slopes characterized by a history as open areas and pastures are especially suitable for grassland species. Corridors suitable for alien species, in turn, are characterized by productive soils and abundant light and are surrounded by a dense urban fabric. Factors controlling species composition in the two groups are somewhat correlated, with the most important factors including light abundance, soil moisture, soil calcium concentration and soil productivity. The results have implications for grassland conservation and invasive alien species control in urban areas.  相似文献   

5.
Pürçek-Aksoy  N.  Kutbay  H. G.  Sürmen  B. 《Biology Bulletin》2021,48(4):483-494
Biology Bulletin - Plant functional traits have been used to obtain maximum information on plant growth and resource-use strategy. Westoby (1998) developed a functional strategy called LHS...  相似文献   

6.
We evaluated puma (Puma concolor) feeding patterns in southeastern Brazilian agricultural landscapes using carbon and nitrogen stable isotope analyses of hair collected from fecal samples (= 64). We classified the samples into three groups: feeding patterns based on forest remnants, on the agricultural matrix or both. We observed a predominance of consumption of C3 prey (~47% of individuals) in the area with the highest proportion of forest coverage. Conversely, C4 prey were highly consumed (~40% of individuals) where the agricultural matrix was predominant. The δ13C values for pumas in both areas indicated that their food resources come from both forest remnants and the agricultural matrix and that some individuals preferentially consumed C4 prey, indicating that food resources from the agricultural matrix make up most of their diet (~46% of prey individuals). The wide range of puma's δ15N values in both areas indicated a diet based on different types of prey. However, the C4 group had higher values, indicating that both pumas and their prey feed on enriched resources from the agricultural matrix. The results confirm the high behavioral plasticity of pumas in using highly anthropogenic habitats. The stable isotope analyses conducted in this study yielded new information on large carnivore trophic ecology that might be useful in the development of new conservation strategies in disturbed areas.  相似文献   

7.
An increasing interest to convert lignocellulosic biomass into biofuels has highlighted the potential of using willows for this purpose, due to its fast growth in short rotation coppice systems. Here, we use a mapping population of 463 individuals of a cross between Salix viminalis and S. viminalis × S. schwerinii to investigate the genetic background of different wood chemical traits, information of importance for breeding towards different uses of wood. Furthermore, using a subset of the mapping population, the correlation between biogas production and chemical traits was investigated. The phenotyping of wood was carried by Furrier-transformed-Infrared spectrometry (FT-IR) and water content analysis. Quantitative trait loci (QTLs) analysis was used to identify regions in the genome of importance for the phenotypic variation of these chemical traits. We found 27 QTLs for various traits. On linkage group (LG) VI-1, QTLs for signals assigned to G-lignin, lignin, and the S/G ratio were collocated and on LG XIV we found a cluster of QTLs representing signals assigned to lignin, cellulose, hemicellulose, and water. The QTLs explained from 3.4 to 6.9% of the phenotypic variation indicating a quantitative genetic background where many genes influence the traits. For the biogas production, a positive and negative correlation was seen with the signals assigned to acetyl and lignin, respectively. This study represents a first step in the understanding of the genetic background of wood chemical traits for willows, information needed for complementary studies, mapping of important genes, and for breeding of varieties for biofuel production purposes.  相似文献   

8.
本文对雪莲花的原植物种类、生境分布、生长习性做了分析整理,并对新疆雪莲、水母雪莲、雪兔子等六种雪莲植物化学成分研究进展进行了综述。从比较已有的实验结果中发现不同种雪莲在其特定生境下的化学成分既有属的同一性又存在种的特征性差异。这不仅为植物化学分类提供了证据,也为细胞大量培养选用品质优秀的原植物材料提供了资料。  相似文献   

9.
Cytological changes occurring after infection by Abutilon Mosaic Virus (AbMV) have been investigated in the host plants Abutilon sellovianum Rgl., Malva parviflora L., Malva silvestris L., and Sida micrantha Schr. Two types of virus-like inclusions were found in different tissues: particles of 16–18 nm in diameter and elongated filaments with 6–8 nm in diameter. The particles are detectable in the nuclei (Abutilon sellovianum, Malva spec.) and cytoplasm (Malva spec.) of cells in the bundle area, and the filaments accumulate in the nuclei (Sida micrantha) and the plastids (Malva spec.) of leaf mesophyll cells.  相似文献   

10.
为揭示生长在湿润生境和季节性干旱生境棕榈科植物的水分生理生态适应的差异,在中国科学院华南植物园中选取3种原分布于湿润生境(SOMH)植物:澳洲轴榈(Licualaramsayi)、槟榔(Arecacatechu)和所罗门皱籽棕(Ptychosperma salomonense),以及3种原分布于季节性干旱生境(SODH)植物:大丝葵(Washingtonia robusta)、澳洲蒲葵(Livistona australis)和大蒲葵(L. saribus),对叶片和叶柄的结构与功能性状进行测定。结果表明,与SODH物种相比,3种SOMH植物的水力加权导管直径(Dh)、理论导水率(Kth)、膨压丧失点(TLP)、脆弱性指数(VI)和比叶面积(SLA)较高,而其叶脉密度(VD)较低。TLP、VI均与Kth呈显著正相关,说明水力效率和水力安全之间存在权衡关系。可见,SOMH棕榈的叶片水力效率高于SODH棕榈,但叶片水力安全低于SODH,这揭示了生长于不同生境棕榈科植物在水分生理生态策略上的差异。  相似文献   

11.
我国雪莲植物的种类、生境分布及化学成分的研究进展   总被引:33,自引:0,他引:33  
本文对雪莲花的原植物种类、生境分布、生长习性做了分析整理,并对新疆雪莲、水母雪莲、雪兔子等六种雪莲植物化学成分研究进展进行了综述。从比较已有的实验结果中发现不同种雪莲在其特定生境下的化学成分既有属的同一性又存在种的特征性差异。这不仅为植物化学分类提供了证据,也为细胞大量培养选用品质优秀的原植物材料提供了资料  相似文献   

12.
Assessment of Coleopteran diversity and abundance was carried out in the lowveld region of Swaziland by pitfall trapping in five distinct habitats. Additionally, the study was to ascertain if any of the families collected illustrated habitat fidelity. 18 coleopteran families, comprising 2903 individuals were collected, with an additional 29 unidentified specimens, totalling 2932 beetles. Numerically, the top five families were the Scarabaeidae (2425), Carabidae (211), Tenebrionidae (149), Nitidulidae (37) and Curculionidae (22). 66.6% of all specimens collected were harboured within the pine windbreak while the lowest number (2.6%) was collected from the mature citrus orchard. The highest proportion (77%) of scarabaeid beetles collected occurred within the pine windbreak. Habitat specificity was illustrated by one family, Meloidae, which was found only in the young orchard. Community analysis was further carried out to ascertain distribution patterns of the dominant coleopteran families. Three scarabaeid species were found only in the pine windbreak while three carabid species occurred only in the indigenous savanna. Significant differences between habitats were observed in the number of beetles collected while no significant differences were observed in terms of the number of families observed in each habitat (p<0.05). Results indicate that conservation of the various habitat patches within the mosaic studied could facilitate conservation of whole communities rather than individual species thus facilitating effective conservation of the agricultural landscape.  相似文献   

13.
植物细胞中的活性氧及其生理作用   总被引:36,自引:1,他引:36  
介绍了植物体中活性氧的产生机制、在植物细胞多种生理活动中的功能及其与其它信号因子的相互作用.  相似文献   

14.
This study was conducted to investigate the uptake, accumulation and the enhanced dissipation of di(2-ethylhexyl) phthalate (DEHP) spiked in soil (with a concentration of 117.4 ± 5.2 mg kg?1) by eleven plants including eight maize ( Zea mays) cultivars and three forage species (alfalfa, ryegrass and teosinte). The results showed that, after 40 days of treatment, the removal rates of DEHP ranged from 66.8% (for the control) to 87.5% (for the maize cultivar of Huanong-1). Higher removal rate was observed during the first 10 days than the following days. Plants enhanced significantly the dissipation of DEHP in soil. Enhanced dissipation amount in planted soil was 13.3–122 mg pot?1 for DEHP, and a net removal of 2.2%–20.7% of the initial DEHP was obtained compared with non-plant soil. The contribution of plant uptake to the total enhanced dissipation was <0.3%, and the enhanced dissipation of soil DEHP might be derived from plant-promoted biodegradation and sorption stronger to the soil. Nevertheless, the capability in accumulation and enhanced dissipation of DEHP from spiked soils varied within different species and cultivars.  相似文献   

15.
正Plant species with extremely small populations(PSESP)refers to plants with unique topography and habitat,extremely limited distribution range,enormous pressure due to habitat destruction and habitat in plant diversity hotspots with poor economic development.PSESP,a new conservation action concept first promulgated in Yunnan Province,is becoming more widely accepted in China.Several national and regional conservation strategies and actions for conser-  相似文献   

16.
Scattered trees support high levels of farmland biodiversity and ecosystem services in agricultural landscapes, but they are threatened by agricultural intensification, urbanization, and land abandonment. This study aimed to map and quantify the decline of orchard meadows (scattered fruit trees of high nature conservation value) for a region in Southwestern Germany for the 1968 2009 period and to identify the driving forces of this decline. We derived orchard meadow loss from 1968 and 2009 aerial images and used a boosted regression trees modelling framework to assess the relative importance of 18 environmental, demographic, and socio-economic variables to test five alternative hypothesis explaining orchard meadow loss. We found that orchard meadow loss occurred in flatter areas, in areas where smaller plot sizes and fragmented orchard meadows prevailed, and in areas near settlements and infrastructure. The analysis did not confirm that orchard meadow loss was higher in areas where agricultural intensification was stronger and in areas of lower implementation levels of conservation policies. Our results demonstrated that the influential drivers of orchard meadow loss were those that reduce economic profitability and increase opportunity costs for orchards, providing incentives for converting orchard meadows to other, more profitable land uses. These insights could be taken up by local- and regional-level conservation policies to identify the sites of persistent orchard meadows in agricultural landscapes that would be prioritized in conservation efforts.  相似文献   

17.
To evaluate the potential of the indigenous plant species for Arsenic (As) phytoremediation, a total of 138 plant samples and 138 soil samples from rooting zones were collected from two As-contaminated areas in Kurdistan, western Iran. The areas were the Sari Gunay Gold Mine (SG) and Ali Abad Village (AA). The soil of both areas naturally contains As, with mining activities at SG. Soil and plant samples were collected at five sites in the SG (SG1 to SG5) and at two sites in the AA (AA1 and AA2). Soil samples were analyzed for total and water-soluble As concentration, as well as for the main soil physical and chemical properties such as electrical conductivity (Ec), pH, organic carbon (Corg.), available phosphorus (Pava.), and soil texture. Plant samples were analyzed for As concentration in their shoots and roots.

The average total and water–soluble As concentrations in soil were 751.6 and 6.2 ppm at SG and 920.8 and 8.0 ppm at AA, respectively. The highest root and shoot As concentration was found in Juncus inflexus (751.5 ppm) at AA2 and in Astragalus gossypinus (158.7 ppm) at AA1, respectively. With regard to phytoremediation strategies, Acantholimon brachystachyum, Astragalus gossypinus, Stipa barbata, and Ephedra major with a high translocation factor (TF) can be potentially used for As phytoextraction. However, Juncus inflexus, Phragmites australis, Bromus tomentellus, and Elymus sp., which show high bioconcentration factor (BCF) and low TF, are suggested as good candidates for As phytostabilization. In general, the TF values of terrestrial plants were higher than those of amphibious plants; meanwhile, BCF values showed the opposite behavior.  相似文献   


18.
BackgroundCutaneous dirofilariosis is a canine mosquito-borne zoonosis that can cause larva migrans disease in humans. Dirofilaria repens is considered an emerging pathogen occurring with high prevalence in Mediterranean areas and many parts of tropical Asia. In Hong Kong, a second species, Candidatus Dirofilaria hongkongensis, has been reported. The present study aimed to compare mitochondrial genomes from these parasites and to obtain population genetic information.ConclusionGenetic differences between Dirofilaria spp. causing cutaneous disease can be considerable whereas D. repens itself was genetically quite homogenous. C. D. hongkongensis was identified for the first time from the Indian subcontinent. The full mitochondrial genome sequence strengthens the hypothesis that it represents an independent species and the Thai samples might represent another cryptic species, Candidatus Dirofilaria sp. ‘Thailand II’, or a quite divergent population of C. D. hongkongensis.  相似文献   

19.
刘志民  K.  THOMPSON  R.  E.SPENCER  R.  J.  READER 《植物学报(英文版)》2000,42(6):628-635
Rooting depth and root and shoot biomass were measured for seedlings of 20 species in both watered and unwatered sand columns. The species were from habitats of widely varying moisture status, ranging from marsh to desert. Moisture status of the species' habitats was quantified as Ellenberg moisture number. Seedlings were allowed to grow in moist sand for 21 days and were then exposed to the treatments (watered and unwatered) for a further 21 days. Rooting depth of control plants was not correlated with Ellenberg number. Riit depth of plants from dry habitats tended to increase in drying sand, while roots of plants from wet habitats decreased in depth. Plasticity of rooting depth (depth in unwatered/depth in watered sand) was significantly correlated with Ellenberg number (r2=0.56). Plasticity of shoot/root ratio was also correlated with Ellenberg number, but the relationship was weaker than for rooting depth plasticity. Species that showed the greatest pasticity in rooting depth also showed the greatest ability to sustain shoot growth in unwatered sand. There was some evidence that growth of plants from very dry habitats was reduced in the watered treatment. Results of this study suggest that a major, although not the only, adaptation of plants of dry habitats is the ability of their seedlings to exploit deeply buried water resources.  相似文献   

20.

Since the 19th century to date, the fungal pathogens have been involved in causing devastating diseases in plants. All types of fungal pathogens have been observed in important agricultural crops that lead to significant pre and postharvest losses. The application of synthetic fungicide against the fungal plant pathogens (FPP) is a traditional management practice but at the same time these fungicides kill other beneficial microbes, insects, animal, and humans and are harmful to environment. The antagonistic microorganism such as bacteria are being used as an alternate strategy to control the FPP. These antagonistic species are cost-effective and eco-friendly in nature. These biocontrol bacteria have a broad mechanism against fungal pathogens present in the phyllosphere and rhizosphere of the plant. The antagonistic bacteria have different strategies against the FPP, by producing siderophore, biofilm, volatile organic compounds (VOCs), through parasitism, antibiosis, competition for limited resources and induce systemic resistance (ISR) in the host plant by activating the immune systems. The commercial bio-products synthesized by the major bacterial species Pseudomonas syringae, Burkholderia cepacia, Streptomyces griseoviridis, Pseudomonas fluorescens and Bacillus subtilis are used to control Fusarium, Pythium, Rhizoctonia, Penicillium, Alternaria, and Geotrichum. The commercial bio-formulations of bacteria act as both antifungal and plant growth regulators. The Plant growth-promoting rhizobacteria (PGPR) played a significant role in improving plant health by nitrogen-fixing, phosphorus solubilization, phytohormones production, minimizing soil metal contamination, and by ACC deaminase antifungal activities. Different articles are available on the specific antifungal activity of bacteria in plant diseases. Therefore, this review article has summarized the information on biocontrol activity of bacteria against the FPP and the role of PGPR in plant growth promotion. This review also provided a complete picture of scattered information regarding antifungal activities of bacteria and the role of PGPR.

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