A recent study by German researchers presents the possibility of " carbon farming" as a less risky alternative to other carbon c

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问题     A recent study by German researchers presents the possibility of " carbon farming" as a less risky alternative to other carbon capture and storage technologies. It suggests that a significant percentage of atmospheric CO2 could potentially be removed by planting millions of acres of a hardy little shrub known as Jatropha curcas, or the Barbados nut, in dry, coastal areas. But other experts raised doubts about the study’s ambitious projections, questioning whether the Barbados nut would be able to grow well in sandy desert soils and absorb the quantity of carbon their models predict.
    The researchers behind the study say Barbados nut plantations could help to mitigate the local effects of global warming in desert areas, causing a decrease in average temperature and an increase in precipitation. If a large enough portion of the Earth were blanketed with carbon farms, they say, these local effects could become global, capturing between 17 and 25 metric tons of CO2 per hectare each year over a 20-year period. The study, published in the journal Earth System Dynamics, states that if 730 million hectares of land—an area about three-quarters the size of the United States—were devoted to this method of carbon farming, the current trend of rising atmospheric CO2 levels could be halted.
    Carbon farms would not compete with food production if they were concentrated in dry coastal areas, the researchers said. In their scenario, oceanside desalination plants, partially powered by biomass harvested from the plantations themselves, provide a low-emission irrigation method. The study states that the Barbados nut is uniquely suited to growing in regions inhospitable to other crops. The plant, which produces a non-edible seed that can be used to create biodiesel, is comfortable growing at temperatures exceeding 100 degrees Fahrenheit. It can also withstand high levels of contamination in the soil, making wastewater another potential source for irrigation.
    The cost of carbon farming is comparable to the costs associated with other carbon capture and storage technologies, the study asserts. The researchers calculated that the total cost for a plantation would be between 42 and 63 per ton of carbon, or between about $55 and $85. The estimated cost of carbon capture technology varies widely, but the nonprofit Center for Climate and Energy Solutions pegs it between $36 and $81, depending on the emissions source. Wulfmeyer stressed that carbon farming could have "fantastic value for the local people" if international carbon markets pick up, promoting rural development and opening up the possibility of additional agriculture as the soil quality improves around the plantation.
    In an email, Van Noordwijk, chief science adviser for the World Agroforestry Center in Bogor, Indonesia, questioned the growth rate and the atmospheric carbon capture rate hypothesized by the study’s authors, calling the estimated carbon price of the plantations a " substantial underestimate". " We’re not talking about trees that create substantive, high-density woody biomass, but about a plant with a shrubby growth habit and a long track record of deceiving farmers with yield potentials that are not being realized," he said. Also, Van Noordwijk said, " even with the abundance of water, the nutrient storage in sandy desert soil is low, and bringing in the nutrient supply to support high growth rates has high energy costs if nitrogenous fertilizer is used. " He added, " The estimated carbon price of this option already indicates that there are far better opportunities for reducing ongoing emissions from peatland use and deforestation. "
What is the attitude of Van Noordwijk towards the study?

选项 A、Interested.
B、Positive.
C、Indifferent.
D、Critical.

答案D

解析 观点态度题。根据题干中的Noordwijk定位至文章最后一段,该段中Noordwijk提出了反对种植桐油树的意见,并从效果和成本等角度进行了分析,认为会有更好的方案,可见,他是持批判态度的,所以[D]正确。[A]“感兴趣的”、[B]“积极的”和[C]“冷漠的”均不符合文意,故排除。
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