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91.
Best management practices compliance monitoring approaches for forestry in the eastern United States
Many of the eastern states that have published best management practices (BMPs) or forest management guidelines have also developed compliance monitoring programs to assess the application of these BMPs or guidelines on public and private forest land. The approaches among these states to collecting on-site monitoring data (measuring compliance) and evaluating sites are variable. A survey of eastern states found that almost all southern states monitor application of BMPs, but proportionally fewer of the northern states have established compliance monitoring programs. The state forestry agencies provide the leadership for these programs in most of the eastern states. States that monitor tend to evaluate all public and private forest landowner categories located within their states. In general, northern states monitor a broader array of site resources (e.g., cultural resources, visual quality) as compared to southern states which focus on water quality and wetlands protection. However, northern states focus their monitoring on timber harvesting, forest road construction and maintenance as compared to southern states which tend to monitor a broader array of forest management activities (e.g., site preparation, reforestation). When selecting sites for monitoring, the most common approach is to select some sites from all landowner categories within the state. Many states do not specify any criteria to identify sites for monitoring so that all sites have an equal chance for selection. Some states do use specific criteria to filter sites for monitoring, most commonly size of forest management activity and proximity to water. 相似文献
92.
Andrew J. Londo 《Water, Air, & Soil Pollution: Focus》2004,4(1):235-243
This study examined the knowledge levels of Mississippi Non Industrial Private Forest (NIPF) landowners. Data were collected by passing out surveys to participants in Best Management Practices (BMP) educational programs held in conjunction with County Forestry Association (CFA) meetings across Mississippi. Ten CFA's participated in this study. Educational program participants were asked to fill out a survey with several demographic and BMP questions prior to the educational program. Results show that BMP program participants owned an average of 113 hectares, whereas the average Mississippi NIPF landowner owns 20 hectares. Responses to BMP related questions show that Mississippi NIPF landowners have a low level of knowledge concerning BMP's. This situation is likely similar to other states in the Southeastern United States. It can be assumed that county forestry association members are more active and informed about managing their forest land. Therefore, these results may overestimate the BMP knowledge level all landowners in Mississippi.Improved educational programs for NIPF landowners, along with better communication between foresters, loggers, and NIPF landowners are needed if BMP's are to be implemented effectively in Mississippi and across the southern region. 相似文献
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塔里木河中游段治理中的牧区水利建设 总被引:1,自引:0,他引:1
塔里木河中下游地区生态环境急剧恶化,最主要的原因是中游段河水近一半21×108m3被人为的散失,造成下游河水所剩无几,致使尾闾台特玛湖干涸。解决的根本办法是将中下游段两岸的农牧民迁出,实现人为耗水为零。近期切实可行的办法是积极开展牧区水利建设,改变牧业生产方式,集中高效利用塔河水资源,发展人工草地,改良天然草场,实现牧业生产生态环境的协调发展,人与自然和谐相处。 相似文献
96.
Forest resources play a key role and provide many basic needs to communities in developing economies. To assess the patterns of vegetation cover change, as a corollary of resource utilization, satellite imagery, ground truth data, and image processing techniques can be useful. This article is concerned with identifying change in major vegetation types in East Timor between 1989 and 1999, using Landsat Thematic Mapper data. The results highlight a significant level of deforestation and decline in foliage cover. All major vegetation cover types declined from 1989 to 1999, and there was a sizeable increase in degraded woodlands. This decline has had considerable impact on the livelihoods of rural and urban communities. Causes for these changes include: economic exploitation of abundant resources; and implications of transmigration policies implemented during Indonesian rule, resulting in increased competition for land and woodland resources. As the new nation of Timor‐Leste establishes itself, it must consider its current stock and distribution of natural capital to ensure that development efforts are geared towards sustainable outcomes. Without the knowledge of historical patterns of resource consumption, development efforts may, unwittingly, lead to continuing decline in forest resources. 相似文献
97.
Ton H. Snelder Barry J.F. Biggs Mark A. Weatherhead 《Journal of the American Water Resources Association》2004,40(1):1-13
ABSTRACT: A method is demonstrated for the development of nutrient concentration criteria and large scale assessment of trophic state in environmentally heterogeneous landscapes. The method uses the River Environment Classification (REC) as a spatial framework to partition rivers according to differences in processes that control the accrual and loss of algae biomass. The method is then applied to gravel bed rivers with natural flow regimes that drain hilly watersheds in New Zealand's South Island. An existing model is used to characterize trophic state (in terms of chlorophyll a as a measure of maximum biomass) using nutrient concentration, which controls the rate of biomass accrual, and flood frequency, which controls biomass loss. Variation in flood frequency was partitioned into three classes, and flow data measured at 68 sites was used to show that the classes differ with respect to flood frequency. Variation in nutrient concentration was partitioned at smaller spatial scales by subdivision of higher level classes into seven classes. The median of flood frequency in each of the three higher level classes was used as a control variable in the model to provide spatially explicit nutrient concentration criteria by setting maximum chlorophyll a to reflect a desired trophic state. The median of mean monthly soluble reactive phosphorus and soluble inorganic nitrogen measured at 68 water quality monitoring sites were then used to characterize the trophic state of each of the seven lower level classes. The method models biomass and therefore allows variation in this response variable to provide options for trophic state and the associated nutrient concentrations to achieve these. Thus it is less deterministic than using reference site water quality. The choice from among these options is a sociopolitical decision, which reflects the management objectives rather than purely technical considerations. 相似文献
98.
分析了当前安全生产管理现状,对林业生产经营单位安全生产管理创新进行探讨,旨在进一步提高安全管理水平。 相似文献
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100.
Michael C. Feller 《Journal of the American Water Resources Association》2005,41(4):785-811
The solution chemistry of forested streams primarily in western North America is explained by considering the major factors that influence this chemistry — geological weathering; atmospheric precipitation and climate; precipitation acidity; terrestrial biological processes; physical/chemical reactions in the soil; and physical, chemical, and biological processes within streams. Due to the complexity of all these processes and their varying importance for different chemicals, stream water chemistry has exhibited considerable geographic and temporal variation and is difficult to model accurately. The impacts of forest harvesting on stream water chemistry were reviewed by considering the effects of harvesting on each of the important factors controlling this chemistry, as well as other factors influencing these impacts ‐ extent of the watershed harvested, presence of buffer strips between streams and harvested areas, nature of post‐harvesting site preparation, revegetation rate following harvesting, pre‐harvesting soil fertility, and soil buffering capacity. These effects have sometimes reinforced one another but have sometimes been counterbalancing or slight so that harvesting impacts on stream water chemistry have been highly variable. Eight major knowledge gaps were identified, two of which — a scarcity of detailed stream chemical budgets and knowledge of longitudinal variation in stream chemistry — relate to undisturbed streams, while the remainder relate to forest harvesting effects. 相似文献