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101.
102.
PDCA循环理论由于管理层次多样、运行程序科学严谨,广泛适用于各项管理工作甚至是管理的各个环节。将其引入国家林业局管理干部学院培训教研室制度建设工作中,通过PDCA循环四阶段进行管理,包括科学制定目标和工作计划、认真组织实施制度建设工作、及时检查结果、积极反馈制度建设中存在的问题,提高了培训教研室制度建设和管理质量,使培训教研室制度建设和管理进一步科学化、规范化。  相似文献   
103.

Context

Managers are faced with numerous methods for delineating wildlife movement corridors, and often must make decisions with limited data. Delineated corridors should be robust to different data and models.

Objectives

We present a multi-method approach for delineating and validating wildlife corridors using multiple data sources, which can be used conserve landscape connectivity. We used this approach to delineate and validate migration corridors for wildebeest (Connochaetes taurinus) in the Tarangire Ecosystem of northern Tanzania.

Methods

We used two types of locational data (distance sampling detections and GPS collar locations), and three modeling methods (negative binomial regression, logistic regression, and Maxent), to generate resource selection functions (RSFs) and define resistance surfaces. We compared two corridor detection algorithms (cost-distance and circuit theory), to delineate corridors. We validated corridors by comparing random and wildebeest locations that fell within corridors, and cross-validated by data type.

Results

Both data types produced similar RSFs. Wildebeest consistently selected migration habitat in flatter terrain farther from human settlements. Validation indicated three of the combinations of data type, modeling, and corridor detection algorithms (detection data with Maxent modeling, GPS collar data with logistic regression modeling, and GPS collar data with Maxent modeling, all using cost-distance) far outperformed the other seven. We merged the predictive corridors from these three data-method combinations to reveal habitat with highest probability of use.

Conclusions

The use of multiple methods ensures that planning is able to prioritize conservation of migration corridors based on all available information.
  相似文献   
104.

Context

Human–nature interactions are reflected in the values people assign to landscapes. These values shape our understanding and actions as landscape co-creators, and need to be taken into account to achieve an integrated management of the landscape that involves civil society.

Objectives

The aim of this research was to increase the current knowledge on the most and least common landscape values perceived by local stakeholders, the patterns in the spatial distribution of values, and their connection to different socio-economic backgrounds and landscape characteristics across Europe.

Methods

The research consisted of a cross-site comparison study on how landscape values are perceived in six areas of Europe using Public Participation GIS surveys. Answers were analysed combining contingency tables, spatial autocorrelation and bivariate correlation methods, kernel densities, land cover ratios, and viewshed analyses. Results were discussed in the light of findings derived from other European participatory mapping studies.

Results

We identified shared patterns in the perception of landscape values across Europe. Recreation, aesthetics, and social fulfilment were the most common values. Landscape values showed common spatial patterns mainly related to accessibility and the presence of water, settlements, and cultural heritage. However, respondents in each study site had their own preferences connected to the intrinsic characteristics of the local landscape and culture.

Conclusions

The results encourage land planners and researchers to approach landscape values in relation to socio-cultural and bio-physical land characteristics comprehensibly, acknowledging the complexity in the relationship between people’s perception and the landscape, to foster more effective and inclusive landscape management strategies.
  相似文献   
105.
CRISPR-Cas technology has raised considerable interest among plant scientists, both in basic science and in plant breeding. Presently, the generation of random mutations at a predetermined site of the genome is well mastered, just like the targeted insertion of transgenes, although both remain restricted to species or genotypes amenable for plant transformation. On the other hand, true genome editing, i.e. the deliberate replacement of one or several nucleotides of the genome in a predetermined fashion, is limited to some rather particular examples that generally concern genes allowing positive selection, for example tolerance to herbicides. Therefore, further technological developments are necessary to fully exploit the potential of genome editing in enlarging the gene pool beyond the natural variability available in a given species. In principle, the technology can be applied to any quality related, agronomical or ecological trait, under the condition of upstream knowledge on the genes to be targeted and the precise modifications necessary to improve alleles. Published proof of concepts concern a wide range of agronomical traits, the most frequent being disease resistance, herbicide tolerance and the biochemical composition of harvested products. The regulatory status of the plants obtained by CRISPR-Cas technology raises numerous questions, in particular with regard to the plants that carry in their genomes the punctual modifications caused by the presence of the Cas9 nuclease but not the nuclease itself. Without clarification by the competent authorities, CRISPR-Cas technology would continue to be a powerful tool in functional genomics, but its potential in plant breeding would remain untapped.  相似文献   
106.
Carbon nanotube (CNT) films are very flexible and serve as active materials for lithium-ion batteries (LIBs). Hence, they have high potential as flexible free-standing electrodes for wearable batteries. However, nanocarbon materials such as CNTs and graphene are of limited use as electrodes because they have a large initial irreversible capacity due to the formation of a solid electrolyte interphase (SEI). Herein, we prelithiated the CNT films to make them available as electrodes for flexible batteries by reducing their irreversible capacity. The SEI is pre-formed through a direct prelithiation (DP) method that brings lithium metal into direct contact with CNT films in an electrolyte. As a result, the capacity of directly-prelithiated CNT film electrodes continues to increase to 1520 mAh/g until 350th cycle of charge/discharge and their initial irreversible capacity vanishes. The changes in the electrochemical properties of CNT film electrodes by DP treatment and their flexibility are investigated.  相似文献   
107.
Background: Nitrogen losses is an economic problem for wheat production and a high risk to the environment. Therefore, improved N fertilizer management is a key to increasing the N efficiency and minimizing N losses. To increase N efficiency, enhanced fertilizers such as urea combined with urease inhibitor can be used. Aims: The aim of present study was to evaluate the effects of different N forms on grain storage protein subunits in winter wheat and to examine whether the observed changes correlate with parameters of baking quality. Methods: The investigation was performed over two consecutive years at two locations in Germany. Protein subunits were analyzed by SDS‐PAGE. Results: Protein concentrations were similarly increased after fertilization with ammonium nitrate and urea + urease inhibitor. Analysis of the individual storage protein fractions indicated that both fertilizers specifically enhanced ω‐gliadins and HMW glutenins, but the effect was more pronounced in the ammonium nitrate treatment. Application of urea + urease inhibitor had greater influence on the protein composition and resulted in higher specific baking volume as well as the best fresh keeping ability, in comparison with urea treatment. Conclusion: Considering that the urea + urease inhibitor treatment resulted in almost comparable improvements of NUE and baking quality, with the additional benefit of reduced N losses in combination with easy handling, urea + urease inhibitor can be recommended as a viable alternative to both urea alone and ammonium nitrate treatments. This opens up an opportunity for the reduction of N loss in wheat production when use of urea is preferred.  相似文献   
108.
Journal of Soils and Sediments - This study analyzes the variability of sediment loads under variant climate change and land use scenarios in a Carpathian catchment with a dam reservoir. The areas...  相似文献   
109.
A water and dye-free heat treatment method was used to color wool fibers. The heat effect changed wool fibers to different colors from white in a nitrogen atmosphere. The influences of heating temperature and time on the colors of wool were investigated and the mechanical property of colored wool fibers was evaluated. The color strength of wool fibers increased as heat treatment temperature and time increased. The tensile strength retention rate of wool fiber was relatively high (≥90 %) when the heat temperature was below 200 °C. The surface morphologies of wool fibers scarcely changed during the heat treatment. The carbon content of fibers was found to reduce by heat treatment, indicating oxidization of components in the wool fibers in the process of coloration. Heat treatment may provide a water and dye-free approach to color wool and other textile fibers, albeit within a limited color range.  相似文献   
110.
Polypyrrole (PPy) film was prepared via in-situ chemical polymerization of pyrrole monomer on the surface of red-clay-brick (RCB) substrate. The deposited PPy film was characterized and used as an adsorbent for removal of benzene polycarboxylic acids from aqueous solutions. The effects of solution pH, contact time, initial concentration, and temperature on the adsorption process were systematically investigated to find the optimum operating conditions. Adsorption kinetic data were best fitted by pseudo-second order kinetic model. The adsorption equilibrium data were most represented by the Freundlich isotherm model. The maximum adsorption amounts of Trimellitic, Hemimellitic, and Pyromellitic acids were 189.27, 177.26, and 203.31 mg/g, respectively. The thermodynamic studies indicate that the adsorption was an endothermic and spontaneous process. Also, the PPy-RCB film was successfully regenerated using sodium hydroxide solution. The regenerated PPy-RCB can be reused for more than four successive cycles with a low reduction in adsorption efficiency.  相似文献   
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