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51.
Many of the world’s rural populations are dependent on the local provision of economically and medicinally important plant resources. However, increasing land-use intensity is depleting these resources, reducing human welfare, and thereby constraining development. Here we investigate a low cost strategy to manage the availability of valuable plant resources, facilitated by the use of isolated Ficus trees as restoration nuclei. We surveyed the plants growing under 207 isolated trees in Assam, India, and categorized them according to their local human-uses. We found that Ficus trees were associated with double the density of important high-grade timber, firewood, human food, livestock fodder, and medicinal plants compared to non-Ficus trees. Management practices were also important in determining the density of valuable plants, with grazing pressure and land-use intensity significantly affecting densities in most categories. Community management practices that conserve isolated Ficus trees, and restrict livestock grazing and high-intensity land-use in their vicinity, can promote plant growth and the provision of important local resources.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0645-9) contains supplementary material, which is available to authorized users.  相似文献   
52.
Raw hide/skins come to the tanners as a by-product of meat industry which is converted into value-added leather as product for fashion market. Leather manufacturing is a chemical process of natural biological matrix. It employs a huge quantity of water and inorganic and organic chemicals for processing and thereby discharges solid and liquid wastes into the environment. One of the potential solid wastes generated from leather industry is chrome-tanned leather shavings (CTLSs), and its disposal is increasingly becoming a huge challenge on disposal to tanners due to presence of heavy metal chromium. Hence, finding a sustainable solution to the CTLS disposal problem is a prime challenge for global tanners and researchers. This paper aims to the deeper review of various disposal methods on CTLS such as protein, chromium, and energy recovery processes and its utilization methodologies. Sustainable technologies have been developed to overcome CTLS solid wastes emanating from leather processing operations. Further, this review paper brings a broader classification of developed methodologies for treatment of CTLSs.  相似文献   
53.
Rice-wheat cropping systems of the Indo-Gangetic plains (IGP) occupying 12 million ha of productive land are important for the food security of South Asia. There are, however, concerns that yield and factor productivity trends in these systems are declining/stagnating in recent years. Decrease in soil organic carbon is often suggested as a reason for such trends. A field experiment was conducted to study the soil organic carbon (SOC) and soil microbial biomass carbon (MBC) dynamics in the rice-wheat systems. Use of organic amendments and puddling of soil before rice transplanting increased SOC and MBC contents. Microbial biomass carbon showed a seasonal pattern. It was low initially, reached its peak during the flowering stages in both rice and wheat and declined thereafter. Microbial biomass carbon was linearly related to SOC in both rice and wheat indicating that SOC could be used as a proxy for MBC.  相似文献   
54.
55.
Six Indian cultivars of Vigna radiata L. (HUM-1, HUM-2, HUM-6, HUM-23, HUM-24 and HUM-26) were exposed with ambient and elevated (ambient + 10 ppb ozone (O3) for 6 h?day?1) level of O3 in open top chambers. Ozone sensitivity was assessed by recording the magnitude of foliar visible injury and changes in various physiological parameters. All the six cultivars showed visible foliar symptoms due to O3, ranging 7.4 to 55.7 % injured leaf area. O3 significantly depressed total chlorophyll, photosynthetic rate (Ps), quantum yield (F v/F m) and total biomass although the extent of variation was cultivar specific. Cultivar HUM-1 showed maximum reduction in Ps and stomatal conductance. The fluorescence parameters also indicated maximum damage to PSII reaction centres of HUM-1. Injury percentage, chlorophyll loss, Ps, F v/F m and total biomass reduced least in HUM-23 depicting highest O3 resistance (R%).  相似文献   
56.
Reductive degradation of the pesticide methoxychlor by photolysis in the presence of hydroquinone in dilute solutions of acetonitrile or 1:1 aqueous t-butanol leads to processes other than simple dechlorination. Direct radical coupling with hydroquinone forms a markedly estrogenic conjugate. A pH dependant molecular rearrangement gives pro-estrogenic 4,4′-dimethoxy-α,α′-dichlorostilbenes, and condensation with hydroquinone yields the chlorine free polycyclic aromatic, 12-hydroxy-3,6-dimethoxybenzo[b]phenanthro[9,10-d]furan.  相似文献   
57.

Problem

Safety belt use in the United States, as measured over daylight hours, has risen steadily over recent years reaching 80% in 2004. Yet, using the National Highway Traffic Safety Administration's (NHTSA) Fatality Analysis Reporting System (FARS), safety belt use among fatally injured front seat outboard occupants of passenger vehicles was only between 42% and 46% for the years 1999 to 2003. One possible contributing factor is that safety belt use at night, when crash rates are highest, is lower than during the day.

Method

A full statewide nighttime belt use observation survey was conducted in 2004. This survey was conducted simultaneously with Connecticut's annual full statewide daytime belt use survey. Night belt use observations of drivers and passengers are possible using newly available near military grade night vision goggles and handheld infrared spotlights. Both day and goggle-assisted night observations were conducted at 100 observation sites in Connecticut. Procedures for day and night observations were as nearly identical as possible.

Results

The night belt use rate was 6.4 percentage points lower than the day rate (83.0 vs. 76.6). Consistent with belt use among Connecticut fatalities, day versus night differences were greatest in urban areas. There was evidence that day versus night differences were greater before as compared to after a May 2004 belt use enforcement program.  相似文献   
58.
Heavy metals, lead (Pb) and mercury (Hg) are non-essential elements. Plants absorb these metals from soil, water and air through their roots and leaves. Heavy metals are the major environmental pollutants, which spread to soil through the use of pesticides, herbicides and micronutrient fertilizers, industrial effluents, decay of junk materials and sewage sludge, vehicular emissions, re-suspended road dust, diesel generator sets and coal-based thermal power plants. Sewage and sludge have contributed to heavy metal contamination of peri-urban lands and vegetable crops. The present review focuses on the effects of various concentrations of Hg on growth of young and mature seedlings as well as on nitrate reductase activity and nitrate assimilation in intact and excised seedling, especially the mechanism underlying nitrate reductase regulation by this heavy metal. Evidence indicates that mercury exerts significant adverse effects on the physiological activity of plants.  相似文献   
59.
The present investigation examined the detoxifying potential of methanolic herbal extracts, namely the leaf and bark extract of Eucalyptus tereticornis, bark extract of Saraca asoca, Cassia fistula and Withania somnifera in vitro using primary chicken embryo fibroblast (CEF) cells against damaging effects of urea and mercuric chloride (HgCl) (II). The influence of 20?mM urea and 10?µM?HgCl (II) was determined on cell viability or proliferation of cells after treatment with plant extracts. Higher survival rate of primary CEF cells treated with higher concentrations of plant extracts was observed due to their protective ability against urea and HgCl (II). Cassia fistula bark extract (10?mg?mL?1) was found to be most effective against 20?mM urea as it protects 90% of CEF cells whereas W. somnifera protects 86% of the cells within 24?h. After treating cells with10?µM HgCl, W. somnifera and E. tereticornis leaf extracts were found to be more effective among all other extracts as they protect approximately 86% and 70% of CEF cells, respectively, within 24?h. These results indicate that C. fistula and W. somnifera has the highest potential amongst all the five plant extracts for protecting CEF cells against damaging effects of urea and HgCl (II), respectively.  相似文献   
60.
Summary The paper outlines environmental problems which are being encountered as a result of attempts to produce economic development in Nepal. Immediate actions are proposed which the author believes are required to counter further environmental degradation.Mr R. P. Chaudhary's current temporary address is c/o Komarov Botanical Institute, Popov-2. Leningrad, 197022, USSR.  相似文献   
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