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631.
632.
Fritz Kleinschroth R. Scott Winton Elisa Calamita Fabian Niggemann Martina Botter Bernhard Wehrli Jaboury Ghazoul 《Ambio》2021,50(1):125
Invasions of water bodies by floating vegetation, including water hyacinth (Eichhornia crassipes), are a huge global problem for fisheries, hydropower generation, and transportation. We analyzed floating plant coverage on 20 reservoirs across the world’s tropics and subtropics, using > 30 year time-series of LANDSAT remote-sensing imagery. Despite decades of costly weed control, floating invasion severity is increasing. Floating plant coverage correlates with expanding urban land cover in catchments, implicating urban nutrient sources as plausible drivers. Floating vegetation invasions have undeniable societal costs, but also provide benefits. Water hyacinths efficiently absorb nutrients from eutrophic waters, mitigating nutrient pollution problems. When washed up on shores, plants may become compost, increasing soil fertility. The biomass is increasingly used as a renewable biofuel. We propose a more nuanced perspective on these invasions moving away from futile eradication attempts towards an ecosystem management strategy that minimizes negative impacts while integrating potential social and environmental benefits.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01360-6) contains supplementary material, which is available to authorized users. 相似文献
633.
634.
Jidapa NithikulObuli. P. Karthikeyan C. Visvanathan 《Resources, Conservation and Recycling》2011,55(4):417-422
The potential reuse of rejects from upstream and downstream process of Mechanical-Biological-Treatment (MBT) plant for the production refuse derived fuel (RDF) was investigated in the present study. Since, the rejects were characterized with the high calorific values of approximately 21 kJ/kg for upstream process and 29.5 kJ/kg for downstream process, both can be considered for RDF production. Further, heavy metal contents were also not exceeding the European standards for using it as RDF is additional benefit. But, RDF production from upstream process rejects showed maximum energy supply of 3.20 × 106 MJ/d with less ash (11.8%), chlorine (0.6%) and sulfur (0.2%) contents than the downstream process rejects. Among the three potential RDF users surveyed, the cement industries showed positive interest to burn RDF in their cement kiln with the energy supply cost of <2.1 USD/GJ. Few technical, economical and safety barriers were also identified with the RDF end users and potential suggestions were discussed for thriving RDF market in Thailand. 相似文献
635.
BEN COLLEN§ JONATHAN LOH† SARAH WHITMEE LOUISE McRAE RAJAN AMIN‡ JONATHAN E. M. BAILLIE‡ 《Conservation biology》2009,23(2):317-327
Abstract: The task of measuring the decline of global biodiversity and instituting changes to halt and reverse this downturn has been taken up in response to the Convention on Biological Diversity's 2010 target. It is an undertaking made more difficult by the complex nature of biodiversity and the consequent difficulty in accurately gauging its depletion. In the Living Planet Index, aggregated population trends among vertebrate species indicate the rate of change in the status of biodiversity, and this index can be used to address the question of whether or not the 2010 target has been achieved. We investigated the use of generalized additive models in aggregating large quantities of population trend data, evaluated potential bias that results from collation of existing trends, and explored the feasibility of disaggregating the data (e.g., geographically, taxonomically, regionally, and by thematic area). Our results show strengths in length and completeness of data, little evidence of bias toward threatened species, and the possibility of disaggregation into meaningful subsets. Limitations of the data set are still apparent, in particular the dominance of bird data and gaps in tropical-species population coverage. Population-trend data complement the longer-term, but more coarse-grained, perspectives gained by evaluating species-level extinction rates. To measure progress toward the 2010 target, indicators must be adapted and strategically supplemented with existing data to generate meaningful indicators in time. Beyond 2010, it is critical a strategy be set out for the future development of indicators that will deal with existing data gaps and that is intricately tied to the goals of future biodiversity targets. 相似文献
636.
秸秆生物型煤走煤能源利用可持续发展之路 总被引:1,自引:0,他引:1
研究出生物型煤的生产工艺流程和最佳化配方,摸索出生物型煤成型主机的合理运行参数,成功试验生产出新型能源生物型煤,为中国煤能源可持续发展利用开辟了新途径,有助于解决成都地区秸秆燃烧造成大气污染问题。 相似文献
637.
水解酸化-生物接触氧化工艺处理麦芽生产废水 总被引:2,自引:0,他引:2
根据麦芽生产废水污染物浓度高且含有较多难降解物质以及企业地处寒冷地区的特点,北方某企业采用以"水解酸化-生物接触氧化"为主体的废水处理工艺,设计并建成了麦芽工业废水处理站.工程运行结果表明,在进水COD、BOD5和SS分别为1 658.2~2 775.4 mg/L、631.4~1 125.6 mg/L和146.8~230 mg/L的情况下,出水水质指标分别为COD 54.4~75.2 mg/L、BOD5 13.4~18 mg/L、SS 15~48.6 mg/L,达到了国家规定的废水一级排放标准.水解酸化-生物接触氧化工艺操作简单,运行稳定性高,能耗低,启动容易,出水水质好,适宜于处理麦芽工业废水,为麦芽工业废水处理工程的设计和运行提供了成功经验. 相似文献
638.
Summary. Surrogate leaves treated with methanolic leaf
surface extracts of Brassica napus L. (cv Express) plants
that received three different sulphur fertilisation treatments
showed even more marked differences by the oviposition
choice of Delia radicum L. than the potted plants. This
confirms that the oviposition preference of D. radicum is
mediated by chemical compounds on the leaf surface and
that the quality of host-plants in terms of their nutrition
status can be perceived by the female insect.The oviposition data were positively correlated with the
content of fractionated surface extracts containing either
CIF (cabbage identification factor; 1,2-dehydro-3-thia-
4,10,10b-triaza-cyclopenta[.a.]fluorine-1-carboxylic acid)
or glucosinolates. Electrophysiological recordings from the
tarsal chemoreceptor sensilla C5 and D3,4 showed that receptor
neurons react to glucosinolate- and CIF-fractions. We
found that the chemosensory activity of specific glucosinolate-
and CIF-receptor neurons corresponded with the
respective behavioural activity in the oviposition choice
assays. The responses of D. radicum to glucosinolates in
the electrophysiological recordings studies corresponded
to the observed oviposition preference on plants or artificial
leaves characterised with an higher amount of glucosinolates
on leave surfaces. The presented data suggested
that CIF and glucosinolates are involved in host-plant
preference of D. radicum and are perceived by tarsal
chemoreceptors. 相似文献
639.
A study was conducted to evaluate the performance of six advanced wastewater treatment facilities using biological nutrient removal processes as the primary mechanism for removing carbon, nitrogen, and phosphorus from domestic wastewater. One year of operating data was obtained from monthly operating reports provided by the Georgia Environmental Protection Division (EPD) in Atlanta. Additional information about facility operations and the types of chemicals used was gathered through review of EPD files and interviews with plant personnel. Data evaluated were: influent and effluent five-day Biochemical Oxygen Demand (BOD(5)); influent and effluent total suspended solids (TSS); influent Total Kjeldahl Nitrogen and effluent Total Nitrogen; and influent and effluent Total Phosphorus (TP). Although varying from plant to plant, effluent requirements for BOD(5), TSS, ammonia, and TP were met. Chemicals utilized, design capacity, and monthly effluent concentrations are presented in this study. 相似文献
640.
We made use of land cover maps, and land use change associated with urbanization, to provide estimates of the loss of natural
resource lands (forest, agriculture, and wetland areas) across the 168,000 km2 Chesapeake Bay watershed. We conducted extensive accuracy assessments of the satellite-derived maps, most of which were produced
by us using widely available multitemporal Landsat imagery. The change in urbanization was derived from impervious surface
area maps (the built environment) for 1990 and 2000, from which we estimated the loss of resource lands that occurred during
this decade. Within the watershed, we observed a 61% increase in developed land (from 5,177 to 8,363 km2). Most of this new development (64%) occurred on agricultural and grasslands, whereas 33% occurred on forested land. Some
smaller municipalities lost as much as 17% of their forest lands and 36% of their agricultural lands to development, although
in the outlying counties losses ranged from 0% to 1.4% for forests and 0% to 2.6% for agriculture. Fast-growing urban areas
surrounded by forested land experienced the most loss of forest to impervious surfaces. These estimates could be used for
the monitoring of the impacts of development across the Chesapeake Bay watershed, and the approach has utility for other regions
nationwide. In turn, the results and the approach can help jurisdictions set goals for resource land protection and acquisition
that are consistent with regional restoration goals. 相似文献