西安广运潭生态景区旅游环境容量研究

建立了一套旅游环境容量指标体系,给出了各指标的含义和计算公式,并据此对西安广运潭生态景区旅游环境容量进行了定量分析,计算出了其值,计算结果较为科学,具有一定的可操作性,对广运潭的规划管理有一定的指导意义。     

国家生态文明试验区(贵州)经济增速与植被恢复协调发展

以国家生态文明试验区(贵州)作为研究区,以植被覆盖度(FVC)作为研究对象,基于2000～2019年的NDVI数据分析了贵州省近20年FVC的时空演变特征,利用地理探测器方法识别并量化了经济持续增速下维持植被恢复的主要驱动力,结果表明:(1)近20年来贵州省FVC整体呈增加趋势,FVC分布整体水平较高,主要以中等、中高和高度覆盖为主,三者面积占比之和约为89.7%,年均增长率为0.52%,平均FVC为0.53.(2)近20年来贵州省FVC变化趋势以轻微改善、基本不变为主,两者面积占比之和为68.94%,改善区域面积占比为57.93%,西部区域得到明显改善和提升,退化区域主要集中在城镇周边,总体动态变化趋于稳定且向好改善.(3)FVC空间分布格局演变深受人类活动与自然环境因子的双重影响,且人类活动对于植被恢复的驱动作用更强,国内生产总值(GDP)和降水是经济持续增速下维持植被恢复的人类活动与自然环境因子主导驱动力.(4)积极推动产业结构优化升级、大力推进第三产业快速发展以及不断贯彻落实退耕还林还草政策等积极的人类活动为贵州省实现经济增速与植被恢复协调发展的“双赢”局面做出了巨大贡献.     

How deep is the footprint? A 3D representation

Depletion of natural capital stocks and use of natural capital flows are the central issues in the sustainability debate. Differentiation of these two components, considering natural capital and its limits, is important for planning and management of land use. This paper offers insights into this issue and proposes a new perspective of the Ecological Footprint (EF) in three dimensions, considering not only its size but also its depth: according to this viewpoint the footprint is not an area but a volume, although maintaining the same value as the one in two dimensions. Use of annual flows provided by the Earth is represented by the footprint size, expressed in global hectares (gha) and plotted in the (x,y) plane. Footprint depth represents the demand for extra land to meet human needs through depletion of stocks of natural capital. It is plotted on the z-axis. It can be seen as the number of years necessary to regenerate resources liquidated in 1 year (and to absorb the respective wastes) or as the number of planets necessary to support the inhabitants of the planet Earth. The evolution of these two components in the last five decades is studied and discussed.     

Analyzing the tradeoffs among ecological and fishing effects on an example fish community: A multispecies (fisheries) production model

Species interactions such as predation or competition can have notable implications for fish population dynamics. Stock status and associated biological reference points can be misrepresented if these interactions are not considered. Here we present a multispecies, biomass production model (MS-PROD) developed by incorporating modifications to the Schaefer production model. The modifications explicitly emphasize a functional group approach, highlighting the effects of species interactions that include competition between species within a group, competition between groups, and predation. The mathematical formulation also includes constraints on carrying capacity for both the entire system and for individual groups. We applied the model as initialized to the Northeast U.S. Large Marine Ecosystem finfish community. We then executed simulations designed to explore the behavior of the model with respect to fishery exploitation and ecological interactions. Collectively, the results demonstrated the utility, and the need, for incorporating ecological effects into fisheries models.     

Hierarchical spatial point process analysis for a plant community with high biodiversity

A complex multivariate spatial point pattern of a plant community with high biodiversity is modelled using a hierarchical multivariate point process model. In the model, interactions between plants with different post-fire regeneration strategies are of key interest. We consider initially a maximum likelihood approach to inference where problems arise due to unknown interaction radii for the plants. We next demonstrate that a Bayesian approach provides a flexible framework for incorporating prior information concerning the interaction radii. From an ecological perspective, we are able both to confirm existing knowledge on species’ interactions and to generate new biological questions and hypotheses on species’ interactions.

An improved approach for identifying suitable habitat of Sambar Deer (Cervus unicolor Kerr) using ecological niche analysis and environmental categorization: Case study at Phu-Khieo Wildlife Sanctuary,Thailand

To assess habitat suitability (HS) has become an increasingly important component of species/ecosystem management. HS assessment is usually based on presence/absence data related to environmental variables. An exception is Ecological Niche Factor Analysis (ENFA), which uses only presence data and which does not require absence data. Most HS modelling is based on input of all environmental parameters (EnvPs) without environmental categorization, and does not take into account species interaction and human intervention for an assessment of HS. In this study, the EnvPs are arranged into four features: geographical features, consumable features, human-factor features, and species–human interaction features. These features affect species with respect to movement, behavior and activity. The research presented here has used an already existing dataset of wildlife species and human activities/visitations, which was compiled during 2004–2006 in Phu-Khieo Wildlife Sanctuary (PKWS). Data from 2004 to 2005 were used to produce HS maps, while the data of 2006 were used for evaluating these maps. Sambar Deer (SD) was chosen to predict its own HS. Six HS maps of SD were analyzed using ENFA in the following manner: (1) inputting all EnvPs together, (2) inputting each feature, separately and (3) integrating the four resulting HS maps by model averaging. It was found that model averaging was capable of predicting the HS of SD more reliably than the model with all EnvPs put in together. Multiple linear regressions were computed between the HS map with all EnvPs and the HS maps with each feature. The results show that the HS map with only geographical features has the highest coefficient value (0.516) while the coefficient values of other HS maps with the above features are 0.296, 0.53 and −0.006, respectively. This indicates that the geographical features have an influence on the other features and that the predicting power is lower when all EnvPs are computed in the ENFA model. Therefore, in order to generate HS, each feature should at first be put into the model separately. Following that, the average of all features will be combined.     

The effects of aggregation on the performance of the inverse method and indicators of network analysis

Food webs are usually aggregated into a manageable size for their interpretation and analysis. The aggregation of food web components in trophic or other guilds is often at the choice of the modeler as there is little guidance in the literature as to what biases might be introduced by aggregation decisions. We examined the impacts of the choice of the a priori model on the subsequent estimation of missing flows using the inverse method and on the indices derived from ecological network analysis of both inverse method-derived flows and on the actual values of flows, using the fully determined Sylt-Rømø Bight food web model. We used the inverse method, with the least squares minimization goal function, to estimate ‘missing’ values in the food web flows on 14 aggregation schemes varying in number of compartments and in methods of aggregation. The resultant flows were compared to known values; the performance of the inverse method improved with increasing number of compartments and with aggregation based on both habitat and feeding habits rather than diet similarity. Comparison of network analysis indices of inverse method-derived flows with that of actual flows and the original value for the unaggregated food web showed that the use of both the inverse method and the aggregation scheme affected indices derived from ecological network analysis. The inverse method tended to underestimate the size and complexity of food webs, while an aggregation scheme explained as much variability in some network indices as the difference between inverse-derived and actual flows. However, topological network indices tended to be most robust to both the method of determining flows and to the inverse method. These results suggest that a goal function other than minimization of flows should be used when applying the inverse method to food web models. Comparison of food web models should be done with extreme care when different methodologies are used to estimate unknown flows and to aggregate system components. However, we propose that indices such as relative ascendency and relative redundancy are most valuable for comparing ecosystem models constructed using different methodologies for determining missing flows or for aggregating system components.     

A model for ecological assessment to pesticide pollution management

Applying the relational analysis in the Grey System Theory and Method, the comprehensive evaluation on five pesticide pollution controlling techniques in the vegetable production has been made and a comprehensive profit (cp–comprehensive cost (cc) evaluation system (composed of 15 comprehensive cost indices and 14 comprehensive profit indices) has been established, with a index optimization matrix of comprehensive cost indices and comprehensive profit indices obtained and a ratio model of comprehensive cost to comprehensive profit (R_cc/cp) built. Results show that the R_cc/cp value of vegetables intercropping soybeans in insect-proof thin film greenhouses is the smallest and the R_cc/cp value of vegetables intercropping taros in insect-proof net greenhouses, pheromones in insect-proof thin film greenhouses, pheromones in insect-proof thin film greenhouses and ground planting (only using chemical pesticide for insect-proof without covering materials and synthetic sex pheromone) other four techniques are 0.6268, 0.6393, 0.6407, 0.9809 respectively. In accordance with the R_cc/cp value, vegetables intercropping soybeans in insect-proof thin film greenhouses can be the most optimized pesticide pollution controlling technique in the vegetable growing.     

生态环境保护与可持续发展

简述了可持续发展提出的历史背景及其内涵,以及生态环境保护在实行可持续发展战略中的地位和作用,指出我国生态环境中存在的问题及其原因,就我国生态环境存在的问题及解决途径作了阐述。