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121.
FINN DANIELSEN HENDRIEN BEUKEMA† NEIL D. BURGESS‡§ FAIZAL PARISH CARSTEN A. BRÜHL†† PAUL F. DONALD‡‡ DANIEL MURDIYARSO§§ BEN PHALAN‡ LUCAS REIJNDERS MATTHEW STRUEBIG††† EMILY B. FITZHERBERT‡‡‡§§§ 《Conservation biology》2009,23(2):348-358
Abstract: The growing demand for biofuels is promoting the expansion of a number of agricultural commodities, including oil palm (Elaeis guineensis). Oil‐palm plantations cover over 13 million ha, primarily in Southeast Asia, where they have directly or indirectly replaced tropical rainforest. We explored the impact of the spread of oil‐palm plantations on greenhouse gas emission and biodiversity. We assessed changes in carbon stocks with changing land use and compared this with the amount of fossil‐fuel carbon emission avoided through its replacement by biofuel carbon. We estimated it would take between 75 and 93 years for the carbon emissions saved through use of biofuel to compensate for the carbon lost through forest conversion, depending on how the forest was cleared. If the original habitat was peatland, carbon balance would take more than 600 years. Conversely, planting oil palms on degraded grassland would lead to a net removal of carbon within 10 years. These estimates have associated uncertainty, but their magnitude and relative proportions seem credible. We carried out a meta‐analysis of published faunal studies that compared forest with oil palm. We found that plantations supported species‐poor communities containing few forest species. Because no published data on flora were available, we present results from our sampling of plants in oil palm and forest plots in Indonesia. Although the species richness of pteridophytes was higher in plantations, they held few forest species. Trees, lianas, epiphytic orchids, and indigenous palms were wholly absent from oil‐palm plantations. The majority of individual plants and animals in oil‐palm plantations belonged to a small number of generalist species of low conservation concern. As countries strive to meet obligations to reduce carbon emissions under one international agreement (Kyoto Protocol), they may not only fail to meet their obligations under another (Convention on Biological Diversity) but may actually hasten global climate change. Reducing deforestation is likely to represent a more effective climate‐change mitigation strategy than converting forest for biofuel production, and it may help nations meet their international commitments to reduce biodiversity loss. 相似文献
122.
通过比较在高盐和低盐条件下活性污泥驯化过程,研究了含盐工业废水生化处理耐盐污泥驯化的可行性、特点及其生物学过程.结果表明以盐份作为选择压力可以驯化出具有高降解活性的耐盐污泥,在NaCl浓度为45 000mg/L,容积负荷为1.6kgCODCr/(m3d)时,其CODCr去除率可达到96.6%.对耐盐污泥的驯化过程中的微生物优势生理群变化分析显示,随着进水盐浓度的增加,耐盐苯乙酸降解微生物生理群数量在15d时间内从109cfu/(gVSS)上升到1011cfu/(g.VSS),成为污泥中的优势生理群. 相似文献
123.
通过对炼化混合废水处理工序进行全过程分析与检测,找出影响外排水达标排放的因素,对加药、释放器及生化系统提出了改造方案,改造后的结果表明,浮选与生化系统的降解能力得到提高,外排水水质明显改善,实现达标排放。 相似文献
124.
125.
一个适用于区域性大气环境模拟的大气光化学模式 总被引:10,自引:2,他引:8
根据“计数物种”法对光化学反应机制的分析,建立了一个适用于区域性光化学反应模拟的模式,该模式能较好地模拟出NO_x、O_3及H_2O_2等大气光化学污染物的变化,在保证模拟准确性的同时,该模式形式简单,有利于在实际大气环境质量模拟中应用. 相似文献
126.
Linda A. Joyce Curtis H. Flather Patricia A. Flebbe Thomas W. Hoekstra Stan J. Ursic 《Environmental management》1990,14(4):489-500
The impact of timber management and land-use change on forage production, turkey and deer abundance, red-cockaded woodpecker
colonies, water yield, and trout abundance was projected as part of a policy study focusing on the southern United States.
The multiresource modeling framework used in this study linked extant timber management and land-area policy models with newly
developed models for forage, wildlife, fish, and water. Resource production was integrated through a commonly defined land
base that could be geographically partitioned according to individual resource needs. Resources were responsive to changes
in land use, particularly human-related, and timber management, particularly the harvest of older stands, and the conversion
to planted pine. 相似文献
127.
Chen Zongliang Zhang Yang Wang Yubao Zhuang Yahui KazuhikoSakamoto Katsunori Kimijim Tadao Suzuki Masahiro Uchiyam Yoshikazu Hashimoto Hisao oht Yasuaki mae NobutoshiHoriuchi Shin Suzuki 《环境科学学报(英文版)》1990,2(1):41-48
The conversion rates of SO2 to SO2-4 and NO2 to HNO3+NO3- are estimated from the field-data obtained in Beijing in summer, 1988. The results show that the conversion rate of NO2 is about four times as much as that of SO2; The conversion rates have a diurnal variation in a day. On the average, the rate of SO2 is estimated to be 4.7% h-1 during the daytime and 3.4% h-1 during the nighttime. Similarly, the rate of NO2 is estimated to be 17.2% h-1 and 12% h-1 respectively. 相似文献
128.
129.
厌氧-好氧生化处理淀粉废水的工程应用 总被引:1,自引:0,他引:1
通过邳州市奋达淀粉有限公司的工程实例,介绍了厌氧-好氧生化处理工艺在处理淀粉生产废水中的应用.该工艺具有处理设施运行稳定,处理效果好的优点,系统出水水质满足《污水排放标准》一级标准要求. 相似文献
130.
利用粳稻品种“合系39”在安宁河流域无控制的地理分期播种试验稻米,在实验室进行稻米生化品质的化验分析;采用统计分析方法,研究了气候生态因子与稻米生化品质的定量关系,找出影响稻米生化品质各组分的关键时期,建立综合关系模型.研究结果表明: 1)气候生态条件对生化品质不同组分影响的关键因子和关键时期不同,一些组分的关键期在齐穗前,一些在齐穗后,一些则从齐穗前持续到齐穗后; 2)温度是影响稻米生化品质含量的主要气候因素,蛋白质、氨基酸和直链淀粉含量与关键期的温度呈直线负相关,支链淀粉含量与关键期的温度呈抛物线关系; 3)温度日较差、日照时数与蛋白质、氨基酸、直链淀粉呈负相关,与支链淀粉呈正相关. 图4表2参10 相似文献