Wildfire Policy and Public Lands: Integrating Scientific Understanding with Social Concerns across Landscapes

Abstract:  Efforts to suppress wildfires have become increasingly problematic in recent years as costs have risen, threats to firefighter safety have escalated, and detrimental impacts to ecosystems have multiplied. Wildfires that escape initial suppression often expand into large, high-intensity summer blazes. Lost is the legacy of smaller fires that likely burned outside extreme weather and fuel conditions and resulted in less severe impacts. Despite the recognized need for modifications to existing policies and practices, resource agencies have been slow to respond. The spread of exotic species, climate change, and increasing human development in wildlands further complicates the issue. New policies are needed that integrate social and ecological needs across administrative boundaries and broad landscapes. These policies should promote a continuum of treatments with active management and reduction of fuel hazard in wildland-urban interface zones and reintroduction of fire in wildlands. Management goals should focus on restoration of the long-term ecological health of the land. Projects that reduce fuel loads but compromise the integrity of soil, water supplies, or watersheds will do more harm than good in the long run. Despite significant ecological concerns, learning to live with fire remains primarily a social issue that will require greater political leadership, agency innovation, public involvement, and community responsibility.     

Ecosystem Management across Ownerships: the Potential for Collision with Antitrust Laws

Abstract:  Cross-boundary ecosystem management is increasingly being advocated to address large-scale ecological issues on forested landscapes. Such management requires information about the age, composition, and distribution of trees and other vegetation in addition to the ability to coordinate management over large areas. In the United States, the forest industry owns and manages a large quantity of biologically productive forest land, and these forests are crucial to the success of regional ecosystem planning. Antitrust laws, such as the Sherman Antitrust Act of 1890, limit the industry's ability to participate in regional ecosystem planning because they restrict the ability of competing firms to coordinate activities and share information. Because antitrust courts do not consider the intentions of violators, achieving conservation or other public policy goals, even when working with government agencies, is not a sufficient defense. Therefore, the real and perceived threat of antitrust litigation is a disincentive to the forest industry's participation in large-scale ecosystem management. Potential solutions to this problem include state immunity statutes and third-party data aggregation.     

森林生态系统中土壤呼吸研究进展

土壤呼吸是土壤微生物活性和土壤肥力的一个重要指标，是土壤碳流通的一个重要过程，也是陆地生态系统碳循环的一个关键部分，对研究全球变化有非常重要影响。文章综述了森林生态系统土壤呼吸的各种测量方法，比较了静态气室法和动态气室法的优缺点，认为动态红外气体分析法是最可靠的方法之一；探讨了影响土壤呼吸速率的各种因素，指出在各生物和非生物因素中，温度对土壤呼吸的影响最大；最后提出了土壤呼吸研究过程中存在的一些问题及今后的发展方向。     

Floristic composition and vegetation ecology of the Malindi bay coastal dune field, Kenya

A short outline is given of the floristic composition, structure and distribution of coastal dune vegetation found at Malindi Bay, Kenya. The area was studied by air photo interpretation and field sampling to determine the relationship of plants to aeolian features. TWINSPAN classification was used to distinguish geomorphological units on the basis of their species composition. In this paper, an inventory and first quantitative analysis of vegetation distribution is presented. We identified 174 plant species from 62 families in the sand dunes and several plant communities are distinguished based on the species content and the connection with morphological units.Papilionaceae with 18 species andPoaceae with 17 species were the most represented families. A distinct zonal distribution of the plant communities was found. The most important plant species are the pioneer vegetation consisting ofHalopyrum mucronatum, Ipomoea pescaprae andScaevola plumieri. The woody shrub species which have colonized the established primary dunes and hummock dunes areCordia somaliensis, Pluchea discoridis, Tephrosia purpurea (dunensis). Succulent herbs were identified in the dune slacks and salt marsh that are moist and damp environments.     

Background levels of heavy metals in plants of different taxonomic groups from a montane rain forest in Sri Lanka

An undisturbed natural reserve area iocated in a tropical montane rain forest at about 1800 m altitude in Sri Lanka served as a study site to investigate and assess the natural background concentration levels of As, Cd, Co, Cu, Ni, Pb and Zn in plants representing different taxonomic groups (divisions) in the plant kingdom. The plants selected were: the lichen,Usnea barbata (old man's beard);Pogonatum sp. (a moss);Lycopodium selago (epiphytic lycopod);Polypodium lanceolatum (epiphytic fern);Bulbophyllum elliae (epiphytic orchid) andActinodaphne ambigua (dicotyledonous large tree). Degree of homogeneity with respect to Cd, Cu, Pb and Zn in homogenised materials of all samples were within acceptable limits, whereasPogonatum sp. showed the highest degree of homogeneity for Pb. In addition to confirming extremely low levels of heavy metals in all plant species, the survey also found that generally the primitive plants,Usnea andPogonatum appear to have a greater tendency to accumulate As, Cd, Co and Pb; in particular,U. barbata appears to be an efficient accumulator for those heavy metals, suggesting its potential use in environmental studies.Actinodaphne ambigua was found to have a specific accumulating ability for nickel. Surface cleaning of theA. ambigua leaves resulted in a substantial decrease in the foliar contents of Cd, Ni, Pb and Zn. Variations in heavy metal contents observed in different plant genera are discussed in terms of their habits and place of growth in the forest. It is anticipated that the background levels presented in this paper from a remote, unpolluted tropical ecosystem will provide useful reference data for comparative environmental studies.     

城郊森林区对城区环境生态影响

城郊森林区正成为城市生态绿地系统的重要组成部分，本文选定常熟市及近郊的虞山国家森林公园作为实验区，根据主要环境影响因子的测试结果，分析探讨城郊森林区对城市区域的生态影响及作用机制，表明森林群落是优于其它下垫面类型的多层，多效，可持续利用的城区环境生物净化器。     

Integrating pattern-based modelling and political ecology in land-use change research: the case of Mexican dry tropics

ABSTRACT

Agricultural and extractive frontiers experiment rapid landscape transformation. Land-Use Sciences and Political Ecology are complementary approaches for analysing how landscape transformations are related to biophysical conditions, and socioeconomic, cultural and political processes developed at global, national and local scales. This study examines such relationships in a long-standing agrarian and resource frontier in southern Mexico for the 1986–2015 period. We combine insights from: (1) a quantitative land use/land cover change pattern-based model, involving a weights of evidence and cellular automata simulations, and (2) a qualitative content analysis of literature and of local actors’ perspectives. Two grand frontier processes have developed in this region: NAFTA-related agrarian transition toward intensification and the establishment of wind farms. Both were triggered by global forces and new forms of land and resources use, but mediated by national-to-local ecological, socioeconomic and political processes, producing particular landscape transformations.     

城市与山地森林地区夏秋季大气CO2浓度变化初探

城市与山地森林地区夏秋季大气ＣＯ２浓度变化初探蒋高明黄银晓韩兴国（中国科学院植物研究所，北京１０００９３）关键词ＣＯ２浓度；城市；森林；北京市．１引言ＣＯ２等温室气体的增加，引起了全球科学家与政治家的关注，温室效应及其带来的一系列生态环境改变即全球...     

千烟洲试区人工林营养元素生物积累的研究

对千烟洲试验区人工林的植物和土壤中１５种营养元素的含量、分布和生物积累特征进行了研究。结果表明,两块人工林土壤中缺乏Ｎ、Ｐ、Ｃａ３种元素,微量营养元素未发现亏缺现象。草本层的养分含量高于乔木层的养分含量。两块人工林的生物吸收系数均以Ｐ、Ｃａ、Ｎ的吸收系数最大,Ｔｉ元素的生物吸收系数最低,其余的养分元素均属弱积累中等摄取的营养元素