伸展区正断层几何形态,掀斜和垂直运动之间的关系...     

Jack.  JA 万素凡 《地震地质译丛》1991,13(2):37-43

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恢复扰动土地—扩大资源基地     

Muncy  JA 张立菲 《世界沙漠研究》1990,(1):20-24

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浅层地震反射方法在地下水和工程研究中的应用     

Hunt.  JA 高景华 《物探化探译丛》1991,(1):22-31

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岩溶地区的公路设计     

费希.  JA  石宏仁 《国土资源信息化》1994,(8):16-18

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Movement of water infiltrated from a recharge basin to wells     

O'Leary DR  Izbicki JA  Moran JE  Meeth T  Nakagawa B  Metzger L  Bonds C  Singleton MJ 《Ground water》2012,50(2):242-255

Local surface water and stormflow were infiltrated intermittently from a 40-ha basin between September 2003 and September 2007 to determine the feasibility of recharging alluvial aquifers pumped for public supply, near Stockton, California. Infiltration of water produced a pressure response that propagated through unconsolidated alluvial-fan deposits to 125 m below land surface (bls) in 5 d and through deeper, more consolidated alluvial deposits to 194 m bls in 25 d, resulting in increased water levels in nearby monitoring wells. The top of the saturated zone near the basin fluctuates seasonally from depths of about 15 to 20 m. Since the start of recharge, water infiltrated from the basin has reached depths as great as 165 m bls. On the basis of sulfur hexafluoride tracer test data, basin water moved downward through the saturated alluvial deposits until reaching more permeable zones about 110 m bls. Once reaching these permeable zones, water moved rapidly to nearby pumping wells at rates as high as 13 m/d. Flow to wells through highly permeable material was confirmed on the basis of flowmeter logging, and simulated numerically using a two-dimensional radial groundwater flow model. Arsenic concentrations increased slightly as a result of recharge from 2 to 6 μg/L immediately below the basin. Although few water-quality issues were identified during sample collection, high groundwater velocities and short travel times to nearby wells may have implications for groundwater management at this and at other sites in heterogeneous alluvial aquifers.  相似文献   

Marine debris from the Oregon Dungeness crab fishery recovered in the Northwestern Hawaiian Islands: identification and oceanic drift paths   总被引：1，自引：0，他引：1  

Ebbesmeyer CC  Ingraham WJ  Jones JA  Donohue MJ 《Marine pollution bulletin》2012,65(1-3):69-75

Two Dungeness crab trap tags and floats lost off the State of Oregon, USA during the 2006-2007 fishing season were recovered 4years later in the Northwestern Hawaiian Islands (NWHI): on Lisianski Island on July 15, 2010; and on Kure Atoll on December 10, 2010. This is the first documented recovery of marine debris from Oregon fisheries in the NWHI. We simulate the oceanic drift tracks of the derelict fishing gear with the Ocean Surface Current Simulator (OSCURS) model using estimated loss dates in Oregon based on interviews with the crab trap owners and known recovery sites and dates in the NWHI. These data confirm the US Pacific Northwest as a source of marine debris deposited in the NWHI and provide enhanced understanding of the oceanic drift pathways of marine debris in the North Pacific Ocean.  相似文献   

Developing multimetric indices for monitoring ecological restoration progress in salt marshes     

Langman OC  Hale JA  Cormack CD  Risk MJ  Madon SP 《Marine pollution bulletin》2012,64(4):820-835

Effective tools for monitoring the status of ecological restoration projects are critical for the management of restoration programs. Such tools must integrate disparate data comprised of multiple variables that describe restoration status, including the condition of environmental stressors, landscape connectivity, ecosystem resilience, and ecological structure and function, while communicating these concepts effectively to a wide range of stakeholders. In this paper we describe the process of constructing multimetric indices (MMIs) for monitoring restoration status for restoration projects currently underway on the eastern coast of Saudi Arabia. During this process, an initial suite of measurements is filtered for response and sensitivity to ecosystem stressors, eliminating measurements that provide little information and reducing future monitoring efforts. The retained measurements are rescaled into comparable domain metrics and assembled into MMIs. The MMIs are presented in terms of established restoration theories, including restoration trajectory and restoration endpoint targets.  相似文献   

羌塘草原野生动物保护的生态补偿成本研究(英文)     

鲁春霞  谢高地  肖玉 《资源与生态学报(英文版)》2012,3(1):20-25

生态保护的成本是生态补偿标准的核心组成部分,一般由直接成本、机会成本和发展成本构成。本文以羌塘自然保护区涉及的那曲地区为例,采用恢复成本法和机会成本法对牧民参与野生动物保护的直接成本和机会成本进行了核算。研究过程中,借用中国草地承载力评估中的标准羊单位,把草地生态系统、草食性野生动物和价值评估有机地联系起来,为草原地区野生动物保护的生态补偿提供了一个有效的评估工具。评估结果表明,那曲地区牧民参与野生动物保护的成本是每年5.69亿元,其中直接成本是1.19亿元,机会成本是4.5亿元,机会成本占总成本的79%。机会成本是由于草食性野生动物的啃食与踩踏导致草场必须禁牧致使牧民放弃的经济收入。显然,羌塘自然保护区草食性野生动物对草场的损害构成了生态补偿的主体。如果按照那曲地区中度以上退化草地的面积计算,则牧民保护野生动物的单位面积成本是每年57元,按照那曲地区人口计算,参与野生动物保护的人均成本是每年1482元。这一结果并不等于生态补偿标准,但可以作为补偿标准的低限。  相似文献   

北京森林碳储量海拔梯度上的变化趋势(英文)   总被引：2，自引：0，他引：2  

肖玉  安凯  杨洋  谢高地  鲁春霞 《资源与生态学报(英文版)》2014,5(2):148-156

像北京这样的中国城市化地区的快速人口和GDP增长已经导致了来自化石燃料的大量CO2排放。森林被认为是最重要的碳汇,可以中和碳排放。本研究基于2009年森林清查数据和森林植被碳含量,采用生物量扩展因子(BEFs)方法评价了北京森林植被碳储量,利用森林凋落物与森林生物量的比例以及凋落物碳含量计算了凋落物碳储量,利用土壤厚度、容重和SOM含量计算了土壤碳储量。我们总结得出,阔叶林是北京森林主要碳库,森林碳储量主要分布在海拔60m的平原地区和60-600m的低山地区。北京森林碳密度几乎随着海拔增加而增加,但是在海拔200-400m地区略有下降,其中植被碳密度在60m的平原地区相对较高,这主要是由于碳密度较高的杨树和落叶松人工林的比例较高以及灌溉、施肥等促进植物碳累积的人工管理措施较多;森林土壤碳密度几乎随着海拔增加而增加,这主要是由于土壤碳输出随着海拔增加而逐渐下降,因为林下种植、灌溉和施肥加速了低海拔地区的土壤异氧呼吸但随着海拔增加而下降,同时海拔200-800m的低山地区常见的土壤侵蚀也会随着林下种植等干扰措施的减少而下降。本研究可以为区域森林生态系统管理者提供保护森林生态系统和改善森林碳储量提供科学知识。  相似文献   

中国能源资源开发的时空格局与潜力评价(英文)   总被引：5，自引：2，他引：3  

马蓓蓓  鲁春霞  张雷  程晓凌 《地理学报(英文版)》2010,20(3):347-356

The issue of China's energy supply security is not only the key problem which affects China's rapid and sustainable development in the 21st century,but also the one which international attention focuses on.Based on the notable characteristic of spatial imbalance between energy production and consumption in China,this paper takes the evolution of China's primary energy resources development(excluding hydropower) from 1949 to 2007 as the study object,with the aim to sum up the evolutive characteristics and laws of China's energy resources development in the past nearly 60 years.Then,based on comprehensive considerations of coal's,oil's and natural gas's basic reserves,qualities,geological conditions,production status,and ecological service function of every province,this paper adopts development potential index(DP)to evaluate the development potential of every province's energy resources,and divide them into different ranks.Conclusions are drawn as follows:(1) Generally speaking,China's gross energy production was increasing in waves from 1949 to 2007.From the viewpoint of spatial patterns,China's energy resources development has shown a characteristic of "concentrating to the north and central areas,and evolving from linear-shaped to "T-shaped" pattern gradually since 1949.(2) The structure evolution of China's energy resources development in general has shown a trend of "coal proportion is dominant but decreasing,while oil and gas proportions are increasing" since 1949.(3) At the provincial scale,China's energy resources development potential could be divided into large,sub-large,general and small ranks,four in all.In the future,the spatial pattern of China's energy production will evolve from "T-shaped" to "∏-shaped pattern".These conclusions will help to clarify the temporal and spatial characteristics and laws of China's energy resources development,and will be beneficial for China to design scientific and rational energy development strategies and plans,coordinate spatial imbalance of energy production and consumption,ensure national energy supply,avoid energy resources waste and disorderly development,and promote regional sustainable development under the globalization background with changeful international energy market.  相似文献