Dovetree (Davidia involucrate), one of the first-class protective plants in China, is a relic species of paleotropical kingdom in Tertiary period, belonging toDavidiaceae with a single genus. In recent years, the incr...Dovetree (Davidia involucrate), one of the first-class protective plants in China, is a relic species of paleotropical kingdom in Tertiary period, belonging toDavidiaceae with a single genus. In recent years, the increase of regional developing projects has led to a sharp decrease of this ancient and rare plant in naturally distributed habitats and natural population. In this paper, the biological and ecological characteristics of Dovetree were described, and the geographically distributed condition of this species in different geologic periods as well as the major reasons for dynamic changes of its population were systematically analyzed in accordance with field researches and references. The investigations conducted in different years by setting up standard sample plots showed that the population number of Dovetree increased yearly in the areas without human interference but decreased yearly in the areas with human interference. With the increase of population density and human activities decreased as the logarithmic curve:Y=?100.7ln(x)+178.09, and it has turned from a dominant population into an endangered population. Based on the former and present studies on Dovetree, some protection strategies were put foreword for protecting this ancient and rare species. Keywords Davidia involucrate - Dovetree - Geographical Distribution - Biological Characteristics - Protection Policy CLC number S718.4 Document code A Article ID 1007-662X(2004)01-0039-06 Foundation Item: This research was coordinated by the National Natural Science Foundation of China (No. 39970591)Biography: Wu Gang (1965-), Male, Professor in Key Laboratory of Systems Ecology, Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.Responsible editor: Chai Ruihai展开更多
The year 2017 saw explosive growth in China's natural gas market, and the apparent consumption was 235.7 billion cubic meters, up 18.2% over the same period of 2016. In 2017, China's domestic production growth...The year 2017 saw explosive growth in China's natural gas market, and the apparent consumption was 235.7 billion cubic meters, up 18.2% over the same period of 2016. In 2017, China's domestic production growth picked up significantly, reaching 145.3 billion cubic meters, an increase of 9%.Natural gas imports grew rapidly, and imported pipeline gas and imported LNG totaled 91.6 billion cubic meters. The trade volume of LNG surpassed that of pipeline gas for the first time since 2012. In 2018, the macro-economy is expected to maintain growth at a moderate-to-high rate. However, driven by favorable factors such as environmental policies, China's demand for natural gas is expected to continue to grow rapidly, and natural gas consumption will maintain double-digit growth, roughly at 12%. Nevertheless, the seasonable imbalance between natural gas supply and demand will remain conspicuous.展开更多
Natural features such as mountain ranges, steep slopes and vegetation prevent human movement from one habitat to another. They prevent the ecological harm from natural phenomenon like erosion and landslide. Forests de...Natural features such as mountain ranges, steep slopes and vegetation prevent human movement from one habitat to another. They prevent the ecological harm from natural phenomenon like erosion and landslide. Forests destruction has brought about deterioration of ecological environment such as increasing soil and water losses. RS （Remote Sensing） and GIS （Geographic Information System） technology have enhanced the eco-environment assessment procedure using eco-environment quality index tool. This paper presents results of the research on the investigation of the potentials of different landscapes on the complex ecosystem of Makeng Village in Fuj Jan Province to act as natural barrier to eco-environmental vulnerability. Vulnerability factors analysed were soil erosion, vegetation cover, land use types, slope and elevation. To see how one factor acts as natural barrier eco-environment stressors, factor maps were overlaid in pairs using ArcGIS 9.2 software and the matrix statistics exported for analysis in Microsoft Excel. The results showed steep slopes naturally limit human activities, growth of big trees and increase soil erosion. Flat and gentle slopes are less vulnerable to erosion. Elevation is among natural barriers to human activities. Human activities decrease with increasing elevation, hence making the eco-environment naturally stable/undisturbed. In this study, eco-vulnerability to erosion decreases with increasing vegetation cover.展开更多
Nigeria is richly endowed with crude oil and natural gas deposits, which are the country＇s main source of energy and foreign exchange earnings. These deposits are concentrated at the Niger Delta region which has attr...Nigeria is richly endowed with crude oil and natural gas deposits, which are the country＇s main source of energy and foreign exchange earnings. These deposits are concentrated at the Niger Delta region which has attracted the presence of multinational oil/gas companies to the area. This paper analyses the impact of oil and gas development on the rich biological diversity of the region and its consequences on the development of the region and the nation at large. The paper further reviews the abject poverty of the oil/gas producing communities whose source of livelihoods, fisheries resources, agricultural soils/farmlands, forests, clean water, fresh air and housing are being destroyed due to poor energy resource management. The magnitude of destruction and frustration is reflected in unending conflict and insecurity in the region leading to many shut-in productions which pose a governance challenge as the country＇s economy and development is heavily dependent on oil and gas production.展开更多
The wetlands of the Brahmaputra valley include lake-like natural water bodies locally known as ＇beel＇, and degenerated lakes, which are often called as swamps. The role of such wetlands in socio-economic condition o...The wetlands of the Brahmaputra valley include lake-like natural water bodies locally known as ＇beel＇, and degenerated lakes, which are often called as swamps. The role of such wetlands in socio-economic condition of the people is significant from various angles. Apart from the wetlands act as the ideal habitats for feeding, nesting and breeding of a large variety of fishes, birds and other aquatic animals, these features maintain the environmental quality of the region. Present study has been conducted primarily in eight selected beels in the Dimoria region, which is located almost at the south-central part of the Brahmaputra valley. The water and soil samples from these wetlands had been collected using random sampling technique and analyzed to know about the nature of degradation of the wetlands. Once highly productive wetland waters now show very low DO, high BOD and COD, indicating dwindling productivity of fish and other aquatic resources. Higher value of pH in soils of most of the wetlands found probably due to the impact of industrial effluents and urban sewage and use of chemical fertilizers in the paddy field of the fringe areas, which again create toxic environment and ultimately reduces fish productivity.展开更多
The round-tailed homed lizard Phrynosoma modestum is cryptically colored and resembles a small stone when it draws legs close to its body and elevates its back. We investigated effectiveness of camouflage in P. modest...The round-tailed homed lizard Phrynosoma modestum is cryptically colored and resembles a small stone when it draws legs close to its body and elevates its back. We investigated effectiveness of camouflage in P. modestum and its dependence on stones by placing a lizard in one of two microhabitats （uniform sand or sand with surface rocks approximately the same size as lizards）. An observer who knew which microhabitat contained the lizard was asked to locate the lizard visually. Latency to detec- tion was longer and probability of no detection within 60 s was higher for lizards on rock background than on bare sand. In arenas where lizards could choose to occupy rock or bare sand, much higher proportions selected rocky backgrounds throughout the day; at night all lizards slept among stones. A unique posture gives P modestum a rounded appearance similar to many natural stones. Lizards occasionally adopted the posture, but none did so in response to a nearby experimenter. Stimuli that elicit the posture are unknown. That P. modestum is better camouflaged among rocks than on bare sand and prefers to occupy rocky areas suggests that special resemblance to rocks （masquerade） enhances camouflage attributable to coloration and immobility.展开更多
Urban remnant natural area (URNA), located in the urban or suburb area, less disturbed by dwellers in the process of urbanization, is an important part of complex urban ecosystem and provides significant opportunity f...Urban remnant natural area (URNA), located in the urban or suburb area, less disturbed by dwellers in the process of urbanization, is an important part of complex urban ecosystem and provides significant opportunity for urban sustainable development. Despite that there is a considerable amount of scientific researches on the urban nature in urban and suburb area, the comprehensive research of URNA is still rare. After analyzing the concept and value of URNA, this paper presented a methodology for comprehensive evaluation of URNA by adopting methods of document analysis, prior-selection process, analytic hierarchy process and vector resemblance-degree. As a result, the comprehensive evaluation index of URNA includes target level A, rule level B(ecological environment value, ecological recreation value, social culture value, scientific research value), index level C( diversity,singularity,nature,area,stability,recreation,landscape element,aesthetics,history,scientific), and index level D(20 items). Each index weight of comprehensive evaluation system of URNA of Shanghai was confirmed finally.展开更多
Impacts on growth of young trees of Pinus Koraiensis of 6 environmental factors of intensityof sunlight, direct sunlight, thickness of soil humus, neighboring trees, upper canopy species, herbs andshrubs were investig...Impacts on growth of young trees of Pinus Koraiensis of 6 environmental factors of intensityof sunlight, direct sunlight, thickness of soil humus, neighboring trees, upper canopy species, herbs andshrubs were investigated on young tree of Pinus Koraiensis and 4 neighboring trees which are consideredthe structural unit of the microenvironment. Results indicated that the 6 environmental factors underinvestigation had effects, to various extents, on growth of the young trees. Based on the findings, suitablegrowing conditions for regenerated young tree of Pinus Koraiensis under forest were identified andcorresponding silvicultural measures were proposed for operational practice.展开更多
基金The National Natural Science Foundation of China (No. 39970591)
文摘Dovetree (Davidia involucrate), one of the first-class protective plants in China, is a relic species of paleotropical kingdom in Tertiary period, belonging toDavidiaceae with a single genus. In recent years, the increase of regional developing projects has led to a sharp decrease of this ancient and rare plant in naturally distributed habitats and natural population. In this paper, the biological and ecological characteristics of Dovetree were described, and the geographically distributed condition of this species in different geologic periods as well as the major reasons for dynamic changes of its population were systematically analyzed in accordance with field researches and references. The investigations conducted in different years by setting up standard sample plots showed that the population number of Dovetree increased yearly in the areas without human interference but decreased yearly in the areas with human interference. With the increase of population density and human activities decreased as the logarithmic curve:Y=?100.7ln(x)+178.09, and it has turned from a dominant population into an endangered population. Based on the former and present studies on Dovetree, some protection strategies were put foreword for protecting this ancient and rare species. Keywords Davidia involucrate - Dovetree - Geographical Distribution - Biological Characteristics - Protection Policy CLC number S718.4 Document code A Article ID 1007-662X(2004)01-0039-06 Foundation Item: This research was coordinated by the National Natural Science Foundation of China (No. 39970591)Biography: Wu Gang (1965-), Male, Professor in Key Laboratory of Systems Ecology, Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.Responsible editor: Chai Ruihai
文摘根据中、墨两国科学协定,在我国对外经委的大力协助下,我们于1984年对墨西哥山地资源的利用进行了为期一个月的访问与考察。 整个考察过程中,我们自始至终贯彻了访问与实地调查相结合的工作方式。考察地区为墨西哥的东南部,先后访问(或调查)了全国林业研究所中部地区林业研究中心及其所属的几个试验站——Texcoco河上游地区的土地保养与恢复、Texcoco湖区造林与牧草种植、Rio Frio林间牧草种植;Chapingo农业自治大学森林系和畜牧系;Xalapa生物资源研究所;Huatusco第六农业局和一个咖啡加工工厂;墨西哥国立自治大学San Andres Tuxtla生物试验站;Caltemaco附近的牧场;Oxkutzcab的一家农户;全国林业研究所San
文摘The year 2017 saw explosive growth in China's natural gas market, and the apparent consumption was 235.7 billion cubic meters, up 18.2% over the same period of 2016. In 2017, China's domestic production growth picked up significantly, reaching 145.3 billion cubic meters, an increase of 9%.Natural gas imports grew rapidly, and imported pipeline gas and imported LNG totaled 91.6 billion cubic meters. The trade volume of LNG surpassed that of pipeline gas for the first time since 2012. In 2018, the macro-economy is expected to maintain growth at a moderate-to-high rate. However, driven by favorable factors such as environmental policies, China's demand for natural gas is expected to continue to grow rapidly, and natural gas consumption will maintain double-digit growth, roughly at 12%. Nevertheless, the seasonable imbalance between natural gas supply and demand will remain conspicuous.
文摘Natural features such as mountain ranges, steep slopes and vegetation prevent human movement from one habitat to another. They prevent the ecological harm from natural phenomenon like erosion and landslide. Forests destruction has brought about deterioration of ecological environment such as increasing soil and water losses. RS （Remote Sensing） and GIS （Geographic Information System） technology have enhanced the eco-environment assessment procedure using eco-environment quality index tool. This paper presents results of the research on the investigation of the potentials of different landscapes on the complex ecosystem of Makeng Village in Fuj Jan Province to act as natural barrier to eco-environmental vulnerability. Vulnerability factors analysed were soil erosion, vegetation cover, land use types, slope and elevation. To see how one factor acts as natural barrier eco-environment stressors, factor maps were overlaid in pairs using ArcGIS 9.2 software and the matrix statistics exported for analysis in Microsoft Excel. The results showed steep slopes naturally limit human activities, growth of big trees and increase soil erosion. Flat and gentle slopes are less vulnerable to erosion. Elevation is among natural barriers to human activities. Human activities decrease with increasing elevation, hence making the eco-environment naturally stable/undisturbed. In this study, eco-vulnerability to erosion decreases with increasing vegetation cover.
文摘Nigeria is richly endowed with crude oil and natural gas deposits, which are the country＇s main source of energy and foreign exchange earnings. These deposits are concentrated at the Niger Delta region which has attracted the presence of multinational oil/gas companies to the area. This paper analyses the impact of oil and gas development on the rich biological diversity of the region and its consequences on the development of the region and the nation at large. The paper further reviews the abject poverty of the oil/gas producing communities whose source of livelihoods, fisheries resources, agricultural soils/farmlands, forests, clean water, fresh air and housing are being destroyed due to poor energy resource management. The magnitude of destruction and frustration is reflected in unending conflict and insecurity in the region leading to many shut-in productions which pose a governance challenge as the country＇s economy and development is heavily dependent on oil and gas production.
文摘The wetlands of the Brahmaputra valley include lake-like natural water bodies locally known as ＇beel＇, and degenerated lakes, which are often called as swamps. The role of such wetlands in socio-economic condition of the people is significant from various angles. Apart from the wetlands act as the ideal habitats for feeding, nesting and breeding of a large variety of fishes, birds and other aquatic animals, these features maintain the environmental quality of the region. Present study has been conducted primarily in eight selected beels in the Dimoria region, which is located almost at the south-central part of the Brahmaputra valley. The water and soil samples from these wetlands had been collected using random sampling technique and analyzed to know about the nature of degradation of the wetlands. Once highly productive wetland waters now show very low DO, high BOD and COD, indicating dwindling productivity of fish and other aquatic resources. Higher value of pH in soils of most of the wetlands found probably due to the impact of industrial effluents and urban sewage and use of chemical fertilizers in the paddy field of the fringe areas, which again create toxic environment and ultimately reduces fish productivity.
文摘The round-tailed homed lizard Phrynosoma modestum is cryptically colored and resembles a small stone when it draws legs close to its body and elevates its back. We investigated effectiveness of camouflage in P. modestum and its dependence on stones by placing a lizard in one of two microhabitats （uniform sand or sand with surface rocks approximately the same size as lizards）. An observer who knew which microhabitat contained the lizard was asked to locate the lizard visually. Latency to detec- tion was longer and probability of no detection within 60 s was higher for lizards on rock background than on bare sand. In arenas where lizards could choose to occupy rock or bare sand, much higher proportions selected rocky backgrounds throughout the day; at night all lizards slept among stones. A unique posture gives P modestum a rounded appearance similar to many natural stones. Lizards occasionally adopted the posture, but none did so in response to a nearby experimenter. Stimuli that elicit the posture are unknown. That P. modestum is better camouflaged among rocks than on bare sand and prefers to occupy rocky areas suggests that special resemblance to rocks （masquerade） enhances camouflage attributable to coloration and immobility.
文摘Urban remnant natural area (URNA), located in the urban or suburb area, less disturbed by dwellers in the process of urbanization, is an important part of complex urban ecosystem and provides significant opportunity for urban sustainable development. Despite that there is a considerable amount of scientific researches on the urban nature in urban and suburb area, the comprehensive research of URNA is still rare. After analyzing the concept and value of URNA, this paper presented a methodology for comprehensive evaluation of URNA by adopting methods of document analysis, prior-selection process, analytic hierarchy process and vector resemblance-degree. As a result, the comprehensive evaluation index of URNA includes target level A, rule level B(ecological environment value, ecological recreation value, social culture value, scientific research value), index level C( diversity,singularity,nature,area,stability,recreation,landscape element,aesthetics,history,scientific), and index level D(20 items). Each index weight of comprehensive evaluation system of URNA of Shanghai was confirmed finally.
文摘Impacts on growth of young trees of Pinus Koraiensis of 6 environmental factors of intensityof sunlight, direct sunlight, thickness of soil humus, neighboring trees, upper canopy species, herbs andshrubs were investigated on young tree of Pinus Koraiensis and 4 neighboring trees which are consideredthe structural unit of the microenvironment. Results indicated that the 6 environmental factors underinvestigation had effects, to various extents, on growth of the young trees. Based on the findings, suitablegrowing conditions for regenerated young tree of Pinus Koraiensis under forest were identified andcorresponding silvicultural measures were proposed for operational practice.
