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811.
This work presents a method of assessing plant conservation effectiveness in a given region, which takes into account the legal, species-centered protection, ecosystem conservation, ex situ conservation, restorations and translocations, reintroductions, and monitoring. In order to illustrate the conservation effectiveness, both legally protected species of plants and threatened species were examined. The conservation effectiveness of legally protected species was estimated to have a low value of 23.328 points (pts) according to the methods of calculation. Habitat conservation is insufficient for these species. Almost 40% of all localities are deprived of any ecosystem protection. The conservation effectiveness of the threatened group of species scored a very low value of 13.46 pts. The major reason for this result is a very low level of species protection. Less than 30% of the threatened taxa are under legal preservation and some species from the Orobanche and Cuscuta genera are treated as harmful organisms, which it is obligatory to control within the province territory. Almost 30% of all localities of threatened species are deprived of any ecosystem protection and only 10% lie inside nature reserves. It is suggested that the conclusion of this investigation be used in the preparation and realization of the regional floristic diversity preservation strategy.Published online  相似文献   
812.
The biological mechanisms regulating methane emission fromnatural wetlands are the focus of this article. A novel techniqueprovides estimates of the distribution of CH4 sources withinan undisturbed soil profile by recording the transient gasdynamics after soil enclosure by deep (50 cm) chamber. Thecombined use of conventional surface and soil chambers across a200-m fen transect allowed us to relate the observed methaneemission to its instant generation and uptake. Surprisingly, themethane generation was relatively constant (9–12 mg CH4-C hr-1 m-2) and highly variable net emission (0.2–20 mg CH4-C hr-1 m-2) was closely correlated (r = –0.809)with methane uptake. In laboratory incubations, CH4 uptakefollowed Michaelis-Menten kinetics. Added chloride and nitrateirrespective of the cation's nature suppressed uptake as a strongnoncompetitive inhibitors (K i 0.5 mM). The methaneformation turned out to be unstable and under anaerobicincubation, the formation of CH4, CO2 andH2displayed sustained weekly oscillations. We conclude that effectsof environmental factors alone are not sufficient topredict the variation in emission, which depends also on metabolic control of respective soil organisms. The multitude ofsuch controls is dependent on diversity of respective soilorganisms and could be grouped into a limited number ofcategories considerably simplifying large-scale simulations.  相似文献   
813.
观测安徽吉阳核电厂址近地面层的气象数据,对该厂址近地面层温度梯度及风廓线规律的适用性进行了分析,通过散点图的形式寻找风速比随稳定度参数的变化特征。结果表明,本区气温日变化符合一般观测规律,四季平均气温有较大差异、温差偏大,春夏两季多易出现逆温,春冬逆温强度较夏季偏大;非中性层结条件下风速比值随稳定度的增强而离散增大。  相似文献   
814.
Mercury (Hg) contents in ten chemical fertilizers were determined, and the e ect of calcium superphosphate (CSP) on the uptake and translocation of Hg in corn seedlings was investigated by pot experiments. CSP was applied at the levels of 0, 66.7, and 133.4 mg P2O5/kg to Hg-treated (2 mg/kg) and untreated soils. CSP had the highest Hg content (5.1 mg/kg), followed by the NPK compound fertilizer 15-5-5 (15% N, 5% P2O5, 5% K2O) (1.2 mg/kg), then by nitrogen fertilizers (except for ammonia sulfate) and potassium fertilizers. Application of CSP did not obviously influence the biomass of corn roots, but it significantly increased the biomass of corn shoots in Hg-treated soil. Application of CSP at the levels of 66.7 and 133.4 mg P2O5/kg did not obviously influence the uptake of Hg by corn seedlings on soils without Hg treatment, but it decreased the Hg uptake of corn seedlings significantly on Hg-treated soils. The transfer coe cient of Hg in corn seedlings improved slightly on soils without Hg treatment, but decreased slightly on Hg-treated soils with the application of CSP. These results implied that CSP could ameliorate Hg toxicity to corn seedlings by inhibiting the uptake and the translocation of Hg in plants on Hg-polluted soils.  相似文献   
815.
融雪剂对园林植物种子萌发的影响   总被引:1,自引:0,他引:1  
李芳  张俊民 《环境科技》2009,22(5):22-24
使用融雪剂是高纬度城市冬季除雪的主要措施之一,但融雪剂中含有的盐类物质可以对园林植物造成伤害。在此研究了融雪剂对刺(Robinia pseudoacacia)、万寿菊(Tagetes erecta)、矮紫薇(Lagerstroemia indiea’Petite pinkie')、草地早熟禾(Poa pratensis)、侧柏(Platycladus orientalis)种子发芽率和相对受害率的影响。试验结果表明:5种植物种子的发芽率随融雪剂浓度的升高而降低.相对受害率则随融雪剂浓度升高而增大。其中草地早熟禾种子时融雪剂最敏感,可以用草地早熟禾种子萌发为指示,间接检验融雪剂对植物的伤害程度。  相似文献   
816.
陆生经济植物浮床去除富营养化水中氮素研究   总被引:2,自引:0,他引:2  
通过玻璃缸静态培养试验,探讨陆生经济植物芹菜(Apium graveolens L).、茼蒿(Chrysanthemum coronarium L).和大蒜(Alliumsativum L).作为人工生物浮岛栽培植物,去除富营养化水体中氮的可行性和净化效果。采用常规耗竭法进行吸收动力学试验,研究植物根系对不同形态氮的吸收特性,为浮床植物遴选提供理论依据。结果表明:芹菜、茼蒿和大蒜在水中生长状况良好,试验前后生物量相对增长了121.24%~330.12%;三种经济植物浮床系统净化效果显著,对水中TN的去除率为44.94%~82.84%,高于空白对照系统(25.15%)。三种植物浮床系统对TN去除效果差异极显著(P0.05),根据这三种植物根系对不同形态氮在不同浓度水平下的吸收特性研究发现,其吸收规律均符合Michaelis-Menten动力学方程,但不同种类植物根系吸收特性存在差异,从而影响不同形态氮的去除效果。其中芹菜对NH4+-N的吸收潜力最大,对NO3--N的亲和力最大,大蒜对NO3--N的吸收潜力最大,对NH4+-N亲和力最大,茼蒿对两种形态氮的吸收能力较差。  相似文献   
817.
A case study for water using network of a Starch industry in the state of Gujarat, India, is undertaken with an aim to reduce demineralised water and freshwater flow rates and consequently the wastewater flow rate. The problem was identified as a multi contaminant, reuse and recycle problem. The freshwater consumption and demineralised water consumption were 100 t/h and 51 t/h respectively before modification and the network was dealing with three major contaminants such as total organic content, total dissolved solids and total suspended solids. A program was developed in MATLAB for analysis using Water Pinch. The improved water using network designed for the present work consumed less demineralised and freshwater. The reductions are of the tune of 28% and 64.38% for demineralised and fresh water respectively. Due to alteration in piping, there will be a saving of 406 026 INR per year, which will be utilized for development of efficient environment policy for the company. The entire concept had been implemented on plant level on 1st February-2009 and the reductions are of the tune of 25% and 60% for demineralised and fresh water respectively.  相似文献   
818.
Characteristics of cadmium (Cd) uptake kinetics and distribution of Cd speciation in the rhizosphere for Cd accumulator and non-accumulator oilseed rape varieties were investigated under nutrient solution and rhizobox soil culture conditions. The results showed that the maximal influx (Vmax) for Cd2+ andKm were significantly different for the two oilseed rape varieties. The value of Vmax for Cd accumulator oilseed rape Zhucang Huazi was two-fold greater than that for oilseed rape Chuan you II-93. The exchangeable Cd concentration in the rhizosphere was significantly lower than in non-rhizospheric soils supplemented with CdSO4 for both the varieties. Carbonate-bound Cd in the rhizosphere of Cd accumulator oilseed rape was significantly higher than that in the rhizosphere of non-accumulator oilseed rape and non-rhizospheric soil. Cd accumulator oilseed rape had a higher Cd2+ affinity and more ability to uptake insoluble Cd in the soil than the non-accumulator oilseed rape.  相似文献   
819.
随着现代工业和城市的迅速发展,人类活动对环境影响越来越大,环境污染也随之日益加重,因此迫切需要寻求切实可行的环保措施。利用植物、发挥植物在环境中的作用进行保护就是一种直接有效的方法。本文着重从净化环境和监测环境两个方面阐述植物在环境保护中的作用。  相似文献   
820.
Soil C sequestration in croplands is deemed to be one of the most promising greenhouse gas mitigation options for Japan's agriculture. In this context, changes in soil C stocks in northern Japan's arable farming area over the period of 1971-2010, specifically in the region's typical Andosol (volcanic ash-derived) and non-Andosol soils, were simulated using soil-type-specific versions of the Rothamsted carbon model (RothC). The models were then used to predict the effects, over the period of 2011-2050, of three potential management scenarios: (i) baseline: maintenance of present crop residue returns and green manure crops, as well as composted cattle manure C inputs (24-34 Mg ha−1 yr−1 applied on 3-55% of arable land according to crop), (ii) cattle manure: all arable fields receive 20 Mg ha−1 yr−1 of composted cattle manure, increased C inputs from crop residues and present C inputs from green manure are assumed, and (iii) minimum input: all above-ground crop residues removed, no green manure crop, no cattle manure applied. Above- and below-ground residue biomass C inputs contributed by 8 major crops, and oats employed as a green manure crop, were drawn from yield statistics recorded at the township level and crop-specific allometric relationships (e.g. ratio of above-ground residue biomass to harvested biomass on a dry weight basis). Estimated crop net primary production (NPP) ranged from 1.60 Mg C ha−1 yr−1 for adzuki bean to 8.75 Mg C ha−1 yr−1 for silage corn. For the whole region (143 × 103 ha), overall NPP was estimated at 952 ± 60 Gg C yr−1 (6.66 ± 0.42 Mg C ha−1 yr−1). Plant C inputs to the soil also varied widely amongst the crops, ranging from 0.50 Mg C ha−1 yr−1 for potato to 3.26 Mg C ha−1 yr−1 for winter wheat. Annual plant C inputs to the soil were estimated at 360 ± 45 Gg C yr−1 (2.52 ± 0.32 Mg C ha−1 yr−1), representing 38% of the cropland NPP. The RothC simulations suggest that the region's soil C stock (0-30 cm horizon), across all soils, has decreased from 13.96 Tg C (107.5 Mg C ha−1 yr−1) in 1970 to 12.46 Tg C (96.0 Mg C ha−1 yr−1) in 2010. For the baseline, cattle manure and minimum input scenarios, soil C stocks of 12.13, 13.27 and 9.82 Tg C, respectively, were projected for 2050. Over the period of 2011-2050, compared to the baseline scenario, soil C was sequestered (+0.219 Mg C ha−1 yr−1) by enhanced cattle manure application, but was lost (−0.445 Mg C ha−1 yr−1) under the minimum input scenario. The effect of variations of input data (monthly mean temperature, monthly precipitation, plant C inputs and cattle manure C inputs) on the uncertainty of model outputs for each scenario was assessed using a Monte Carlo approach. Taking into account the uncertainty (standard deviation as % of the mean) for the model's outputs for 2050 (5.1-6.1%), it is clear that the minimum input scenario would lead to a rapid decrease in soil C stocks for arable farmlands in northern Japan.  相似文献   
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