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351.
Abstract:  Traditional ecological knowledge can be highly informative and integrated with complementary scientific knowledge to improve species management. This is especially true for abundant species with which indigenous peoples have frequent interactions (e.g., through harvest), but has been studied less frequently in isolated or declining species. We examined Maori traditional ecological knowledge of tuatara ( Sphenodon spp., reptiles that resemble lizards but are the last living representatives of the order Sphenodontia) through semidirected interviews of elders of Te Atiawa, Ngati Koata, and Ngati Wai Iwi (similar to tribes), the guardians of several islands currently inhabited by tuatara. Maori are indigenous to New Zealand, having settled 800 to 1000 years ago. Tuatara are endemic to New Zealand, have declined in numbers since human settlement, and are now restricted to 37 offshore islands. The detail and volume of tuatara traditional ecological knowledge were less than that recorded in studies of more abundant or accessible species. In addition, traditional knowledge of the cultural significance of tuatara was more common and detailed among the elders than traditional knowledge of tuatara biology or ecology. The traditional knowledge collected, however, provided the first evidence of seven former sites of tuatara occupation, suggested five additional sites tuatara may currently occupy, contained novel hypotheses for scientific testing, and described tuatara cultural roles that have not been reported previously. We conclude that, in at least some cases, traditional ecological knowledge may persist as species decline and may serve as a valuable source of ecological information for conservation .  相似文献   
352.
本文采用多目标灰色局势决策的方法,以桐麦间作人工群落为例,以10年为泡桐生长的一个轮伐期,以6种不同的空间配置方式作为对策,以林业经济收益、农业经济收益和系统总体效益为目标,进行多目标决策,定量研究其空间分布格局。研究结果表明,以农为主间作型泡桐的最佳株行距为5×40m,以桐为主间作型的为5×5m,农桐并重间作型的为5×20m。  相似文献   
353.
鼓泡塔中有机酸强化粗颗粒石灰石新型烟气脱硫   总被引:5,自引:0,他引:5  
对传统石灰石湿法烟气脱硫进行了改进,提出了一种新型烟气脱硫方法,即在鼓泡塔中添加有机酸,采用大颗粒石灰石(210 μm)代替传统的细颗粒石灰石(5~20 μm)进行脱硫.实验在鼓泡搅拌吸收反应器中对比研究了新老两种脱硫工艺.结果表明,当210 μm石灰石浆液中醋酸摩尔浓度达10~30 mmol/L,其脱硫率和石灰石利用率分别为95%和93.5%,均达到甚至优于传统石灰石脱硫结果.实验研究了影响脱硫率的各种因素:添加醋酸浓度、入口SO2浓度、石灰石浆液浓度、气体停留时间以及温度等,并提出添加醋酸促进SO2吸收的机理.运用该新型烟气脱硫方法,可降低电厂的基础投资和运行费用,大大加强系统的稳定性和抗击烟气中SO2波动的能力.  相似文献   
354.
During the 1980s, the exponential growth of laughing gull (Larus atricilla) colonies, from 15 to about 7600 nests in 1990, in the Jamaica Bay Wildlife Refuge and a correlated increase in the bird-strike rate at nearby John F. Kennedy International Airport (New York City) led to a controversy between wildlife and airport managers over the elimination of the colonies. In this paper, we review data to evaluate if: (1) the colonies have increased the level of risk to the flying public; (2) on-colony population control would reduce the presence of gulls, and subsequently bird strikes, at the airport; and (3) all on-airport management alternatives have been adequately implemented. Since 1979, most (2987, 87%) of the 3444 bird strikes (number of aircraft struck) were actually bird carcasses found near runways (cause of death unknown but assumed to be bird strikes by definition). Of the 457 pilot-reported strikes (mean = 23 ± 6 aircraft/yr, N= 20 years), 78 (17%) involved laughing gulls. Since a gull-shooting program was initiated on airport property in 1991, over 50,000 adult laughing gulls have been killed and the number of reported bird strikes involving laughing gulls has declined from 6.9 ± 2.9 (1983–1990) to 2.6 ± 1.3 (1991–1998) aircraft/yr; nongull reported bird strikes, however, have more than doubled (6.4 ± 2.6, 1983–1990; 14.9 ± 5.1, 1991–1998). We found no evidence to indicate that on-colony management would yield a reduction of bird strikes at Kennedy Airport. Dietary and mark–recapture studies suggest that 60%–90% of the laughing gulls collected on-airport were either failed breeders and/or nonbreeding birds. We argue that the Jamaica Bay laughing gull colonies, the only ones in New York State, should not be managed at least until all on-airport management alternatives have been properly implemented and demonstrated to be ineffective at reducing bird strikes, including habitat alterations and increasing the capability of the bird control unit to eliminate bird flocks on-airport using nonlethal bird dispersal techniques. Because the gull-shooting program may be resulting in a nonsustainable regional population of laughing gulls (>30% decline), we also recommend that attempts be made to initiate an experimental colony elsewhere on Long Island to determine if colony relocation is a feasible management option.  相似文献   
355.
ABSTRACT: Hydrological and geochemical spatial patterns and temporal trends were analyzed using U.S. Geological Survey (USGS) water quality data collected from 1975 to 1999 along the uppermost 600 km of the Rio Grande in Colorado and New Mexico. Data on discharge, specific conductivity (SC), total dissolved solids (TDS), pH, Ca2+, Na+, Mg2+, K+, HCO3?, SO42‐, Cl?, F?, and SiO2 came from six USGS stations ranging from the Colorado‐New Mexico border to below Albuquerque, New Mexico. Linear regression, Kendall's S, and Seasonal Kendall's S’ were used to detect trends, and ANOVA was used to analyze spatial differences between stations. Statistically significant increasing trends occurred in SC, TDS, Ca2+, Na+, Mg2+, K+, Cl?, and F?in the uppermost reaches, and significant decreasing trends of SC, TDS, Ca2+, Mg2+, K+, HCO3?, and SO42‐occurred at the lower stations around Albuquerque. Both fluoride concentrations and pH values increased at and below Albuquerque over the study period. Discharge data show an increasing trend across all stations. Spatially, data for dissolved substances show generally linear upstream to downstream increases in concentrations in the upper four stations, with several notable nonlinear increases at and below Albuquerque (SC, TDS, Na+, Cl?). Significant increases in pH appear at and below Albuquerque, relative to upstream stations, probably due to improved sewage treatment.  相似文献   
356.
本文提出了物种相对多度几何级数分布模型的一种新算法即极大值算法,其公式如下: N′_i=N·G_b·(1-b)·b~(i-1) N_(max)/N=[(1-b)·b~(i-1)]/(1-b~s) 式中,N′_i为第i个物种的期望个体数目;N为实测总个体数;i=1,2,…,s为物种数目;C_b=(1-b~s)~(-1);b为参数;N_(max)为s个物种中最多个体数目。 结果表明:几何级数分布模型极大值算法与传统算法(即极小值算法)的结果完全一致,而且具有简便、准确之优点。  相似文献   
357.
秋浇是河套灌区传统的秋后淋盐、春季保墒的一种特殊灌溉制度 ,秋浇对不同类型农田盐分损失影响的试验结果表明 ,秋浇前白菜地土壤含水率最高 ,向日葵地最低 ,秋浇后 5种农田土壤含水率均较高 ,且彼此间无显著性差异。秋浇后不同土壤剖面盐分的损失量按照表层 (0~ 40cm)、中层 (40~ 80cm)、深层 (80~ 1 2 0cm)依次递减(向日葵地除外 )。不同农田的盐分淋失量按照白菜地、向日葵地、玉米地、小麦 -玉米地、小麦地依次递减。非生长季灌溉下 ,农田土壤 0~ 1 0 0cm土层中盐分的淋失量与土壤储水量的增加量 (灌溉前土壤含水率 <2 50 g·kg- 1 ,r =0 .990 2 )密切相关 ,但与灌溉前土壤盐分初始含量无显著性关系  相似文献   
358.
Coordinated voluntary approaches to Pollution Prevention are widely practiced in many western-style economies. However, little empirical research has been undertaken into the extent to which these approaches match best practice pollution prevention approaches. In this paper nine programs employed by five regional and district councils in New Zealand are evaluated against nine ‘Best Practice’ design features. All five councils’ pollution prevention programs contained some of the best practice design features in their program’s design. Perhaps not surprisingly the older programs rank highest out of the five. However, all programs have the potential to develop towards containing all of the ‘best practice’ design features, with most emphasis needed on the credibility of program monitoring. From an ongoing research perspective, and also from an overall PP program performance point of view, the biggest challenge remains the extent and depth that the programs apply each of the design features. As presented they are extremely generic. While generic design features provide for flexibility in implementation, often seen as a positive, they can also be a recipe for ‘tokenism’, something that future researchers and program managers need to be aware of. We also sought to determine if these programs were contributing to sustainable management in New Zealand. Findings in this respect were equivocal. This finding in part is due to the lack of specificity around targets, monitoring and reporting, items needing further attention from managers and researchers.  相似文献   
359.
冯树常  熊华南 《灾害学》1999,14(3):7-11
针对防治法-水利工程防洪法的缺点,提出一个全新的防洪思路-气象工程防洪法,通过从源头控制引起洪涝灾害的水源-降水的时空分布,达到控制水患灾害和充分合理利用水资源的目的,既可减少灾损,节省用于防洪的大量人力物力财力。  相似文献   
360.
Philip L. Shearman 《Ambio》2010,39(2):181-189
Existing at the interface of land and sea, in regions of low topographic relief, mangroves are likely to be some of the first ecosystems that undergo spatial modification due to sea-level rise. The mangrove ecosystems of the Gulf of Papua New Guinea are some of the largest and most pristine in the Asia–Pacific region; they have not been subject to clearance for crustacean farming nor suffered from land reclamation projects. This article establishes through analysis of a time series of aerial photography and satellite imagery from the period 1973–2007, that there have been substantial changes in the distribution of mangroves in this region. These changes include the seaward progradation of the Purari Delta and the regression of the Kikori Delta by an average of 43 m year−1 at its most seaward point. While these findings are likely to be continuations of long-term trends, it is probable that they can be explained by a variety of interacting factors including climate change, sea-level rise, subsistence in the northern Gulf of Papua and changes in sediment dynamics.  相似文献   
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