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1.
Soil physical and chemical properties were quantified to assess soil organic carbon (SOC) density (t ha -1) and SOC CO2 mitigation (t ha -1) under six forest strata Cedrus deodara (closed) (S1), Cedrus deodara (open) (S2), Abies pindrow-Picea smithiana (closed) (S3), Abies pindrow-Picea smithiana (open) (S4), Pinus wallichiana (closed) (S5) and Pinus wallichiana (open) (S6) in the southern region of Kashmir Himalayas India. Lowest average bulk density (D b) of 0.95 was found same in S3 (σ?±?0.07) and S5 (σ?±?0.09) and highest D b (1.08) was observed in S2 (σ?±?0.05). A relatively higher coarse fraction was observed in all the six strata ranging from 19.23 (SD?±?4.66) in S3 to 29.37 (σ?±?6.12) in S6. Soil pH ranged from 6.09 (σ?±?0.64) in S4 to 6.97 (σ?±?0.53) in S2. The region under biotic interference has observed significant deforestation and degradation in the past two decades leading to lower SOC% values compared to other studies in the adjoining regions of Indian Himalayas and temperate coniferous forests in general. SOC% values were observed to range from 1.03 (σ?±?0.22) in S2 to 2.25 (σ?±?0.23) in S3. SOC density ranged between 25.11 (σ?±?5.41) t ha -1 in S2 and 51.93 (σ?±?5.24) t ha -1 in S3. SOC CO2 mitigation density was found highest 190.59 (σ?±?19.23) t ha -1 in S3 and lowest 92.16 (σ?±?19.86) t ha -1 in S2. A significant variation was observed in SOC density within strata. SOC density values in closed strata in general exceed to those in open strata. Primary results indicate that the average SOC stock for all the strata is low due to continuous biotic pressure in the last two decades making it a potential region for SOC buildup under plus options of REDD + (Reducing emissions from deforestation and forest degradation) which includes conservation, sustainable management of forests and enhancement of forest carbon (C) stocks. 相似文献
2.
Reducing carbon emissions from deforestation and degradation in developing countries is of the central importance in efforts to combat climate change. A study was conducted to measure carbon stocks in various land-use systems including forms and reliably estimates the impact of land use on carbon (C) stocks in the forest of Rajasthan, western India (23°3′–30°12′N longitude and 69°30′–78°17′E). 22.8% of India is forested and 0.04% is the deforestation rate of India. In Indian forest sector of western India of Aravally mountain range covered large area of deciduous forest and it’s very helpful in carbon sequestration at global level. The carbon stocks of forest, plantation (reforestation) and agricultural land in aboveground, soil organic and fine root within forest were estimated through field data collection. Results revealed that the amount of total carbon stock of forests (533.64?±?37.54 Mg·ha ?1, simplified expression of Mg (carbon) ·ha ?1) was significantly greater ( P?<?0.05) than the plantation (324.37?±?15.0 Mg·ha ?1) and the agricultural land (120.50?±?2.17 Mg·ha ?1). Soil organic carbon in the forests (172.84?±?3.78 Mg·ha ?1) was also significantly greater ( P?<?0.05) than the plantation (153.20?±?7.48 Mg·ha ?1) and the agricultural land (108.71?±?1.68 Mg·ha ?1). The differences in carbon stocks across land-use types are the primary consequence of variations in the vegetation biomass and the soil organic matter. Fine root carbon was a small fraction of carbon stocks in all land-use types. Most of the soil organic carbon and fine root carbon content was found in the upper 30-cm layer and decreased with soil depth. The aboveground carbon (ABGC): soil organic carbon (SOC): fine root carbon ratios (FRC), was 8:4:1, 4:5:1, and 3:37:1 for the forest, plantation and agricultural land, respectively. These results indicate that a relatively large proportion of the C loss is due to forest conversion to agricultural land. 相似文献
3.
Tropical peat swamp forests, which are predominantly located in Southeast Asia (SEA) and play a prominent role as a global carbon store, are being intensively degraded and converted to agricultural lands and tree plantations. For national inventories, updated estimates of peat emissions of greenhouse gases (GHG) from land use (LU) and land-use change in the tropics are required. In this context, we reviewed the scientific literature and calculated emission factors of peat net emissions of carbon dioxide (CO 2), methane (CH 4) and nitrous oxide (N 2O) in seven representative LU categories for SEA i.e. intact peat swamp forest, degraded forest (logged, drained and affected by fire), mixed croplands and shrublands, rice fields, oil palm, Acacia crassicarpa and sago palm plantations. Peat net CO 2 uptake from or emissions to the atmosphere were assessed using a mass balance approach. The balance included main peat C inputs through litterfall and root mortality and outputs via organic matter mineralization and dissolved organic carbon. Peat net CO 2 loss rate from degraded forest, croplands and shrublands, rice fields, oil palm, A. crassicarpa and sago palm plantations amounted to 19.4?±?9.4, 41.0?±?6.7, 25.6?±?11.5, 29.9?±?10.6, 71.8?±?12.7 and 5.2?±?5.1 Mg CO 2 ha ?1 y ?1, respectively. Total peat GHG losses amounted to 20.9?±?9.4, 43.8?±?6.8, 36.1?±?12.9, 30.4?±?10.6, 72?±?12.8 and 8.6?±?5.3 Mg CO 2-equivalent ha ?1 y ?1 in the same LU categories, respectively. A single land-clearing fire would result in additional emissions of 493.6?±?156.0 Mg CO 2-equivalent ha ?1. 相似文献
4.
Leaf beetles are able to climb on smooth and rough surfaces using arrays of micron-sized adhesive hairs (setae) of varying morphology. We report the first in vivo adhesive force measurements of individual setae in the beetle Gastrophysa viridula, using a smooth polystyrene substrate attached to a glass capillary micro-cantilever. The beetles possess three distinct adhesive pads on each leg which differ in function and setal morphology. Visualisation of pull-offs allowed forces to be measured for each tarsal hair type. Male discoidal hairs adhered with the highest forces (919?±?104?nN, mean?±?SE), followed by spatulate (582?±?59?nN) and pointed (127?±?19?nN) hairs. Discoidal hairs were stiffer in the normal direction (0.693?±?0.111?N?m ?1) than spatulate (0.364?±?0.039?N?m ?1) or pointed (0.192?±?0.044?N?m ?1) hairs. The greater adhesion on smooth surfaces and the higher stability of discoidal hairs help male beetles to achieve strong adhesion on the elytra of females during copulation. A comparison of pull-off forces measured for single setae and whole pads (arrays) revealed comparable levels of adhesive stress. This suggests that beetles are able to achieve equal load sharing across their adhesive pads so that detachment through peeling is prevented. 相似文献
5.
Habitat fragmentation and degradation are important biodiversity change drivers worldwide. Their effects have been described for many animal groups, but little is known about marsupials. We conducted a meta-analysis aiming to evaluate the actual effects of habitat fragmentation and degradation on forest marsupials. From a literature survey, we obtained 85 case studies reporting disturbance comparisons. We found a negative overall effect, as well as a negative effect for habitat fragmentation, but not for habitat degradation. Marsupials from Oceania were negatively affected by habitat disturbance, whereas there was no effect for those from South America. Arboreal marsupials were negatively affected, whereas terrestrial marsupials did not. Species from the families Dasyuridae ( Antechinus spp.) and Microbiotheriidae ( Dromiciops gliroides) showed to be sensitive to habitat disturbance. 相似文献
6.
To date, only a few attempts have been done to estimate the contribution of Mediterranean ecosystems to the global carbon cycle. Within this context, shrub species, composition and structure of the Mediterranean shrublands developing along the Latium coast (Italy) were analyzed in order to evaluate their contribution to carbon (C) sequestration, also taking into consideration the economic benefits at a national level. The considered shrublands had a shrub density of 1,200?±?500 shrubs ha ?1. Shrubs were classified into small (S), medium (M) and large (L), according to their volume (V) and leaf area index (LAI). The total yearly carbon dioxide (CO 2) sequestration per species (SC y) was calculated multiplying the total photosynthetic leaf surface area (spt) of each species by the mean yearly photosynthetic rate and the total yearly photosynthetic activity time (in hours). Q. ilex and A. unedo had the highest SC y (46.2?±?15.8 kg CO 2 year ?1, mean value), followed by P. latifolia (17.5?±?6.2 kg CO 2 year ?1), E. arborea, E. multiflora, C. incanus, P. lentiscus, R. officinalis, and S. aspera (6.8?±?4.2 kg CO 2 year ?1, mean value). The total yearly CO 2 sequestration per shrub (SC shy) was 149?±?5 kg CO 2 year ?1 in L, decreasing 30 % in M and 80 % in S shrubs. Taking into account the frequency of S, M and L and their SC shy, the total CO 2 sequestration of the Mediterranean maquis was quantified in 80 Mg CO 2 ha ?1?year ?1, corresponding to 22 Mg C ha ?1?year ?1. From a monetary viewpoint, this quantity could be valued to more than 500 US$ ha ?1?year ?1. Extending this benefit to the Mediterranean shrublands throughout the whole country, we obtained a nationwide estimated annual benefit in the order of $500 million. 相似文献
7.
The cumulative effects of global change, including climate change, increased population density and domestic waste disposal, effluent discharges from industrial processes, agriculture and aquaculture will likely continue and increases the process of eutrophication in estuarine environments. Eutrophication is one of the leading causes of degraded water quality, water column hypoxia/anoxia, harmful algal bloom (HAB) and loss of habitat and species diversity in the estuarine environment. The present study attempts to characterize the trophic condition of coastal estuary using a simple tool; trophic index (TRIX) based on a linear combination of the log of four state variables with supplementary index Efficiency Coefficient (Eff. Coeff.) as a discriminating tool. Numerically, the index TRIX is scaled from 0 to10, covering a wide range of trophic conditions from oligotrophic to eutrophic. Study area Kodungallur-Azhikode Estuary (KAE) was comparatively shallow in nature with average depth of 3.6?±?0.2?m. Dissolve oxygen regime in the water column was ranged from 4.7?±?1.3?mgL ?1 in Station I to 5.9?±?1.4?mgL ?1 in Station IV. The average nitrate-nitrogen (NO 3-N) of KAE water was 470?mg?m ?3; values ranged from Av. 364.4?mg?m ?3 at Station II to Av. 626.6?mg?m ?3at Station VII. The mean ammonium-nitrogen (NH 4 + -N) varied from 54.1?mg?m ?3 at Station VII to 101?mg?m ?3 at Station III. The average Chl- a for the seven stations of KAE was 6.42?±?3.91?mg?m ?3. Comparisons over different spatial and temporal scales in the KAE and study observed that, estuary experiencing high productivity by the influence of high degree of eutrophication; an annual average of 6.91 TRIX was noticed in the KAE and seasonal highest was observed during pre monsoon period (7.15) and lowest during post monsoon period (6.51). In the spatial scale station V showed high value 7.37 and comparatively low values in the station VI (6.93) and station VII (6.96) and which indicates eutrophication was predominant in land cover area with comparatively high water residence time. Eff. Coeff. values in the KAE ranges from ?2.74 during monsoon period to the lowest of ?1.98 in pre monsoon period. Present study revealed that trophic state of the estuary under severe stress and the restriction of autochthonous and allochthonous nutrient loading should be keystone in mitigate from eutrophication process. 相似文献
8.
A dynamic growth model (CO2FIX) was used for estimating the carbon sequestration potential of sal ( Shorea Robusta Gaertn. f.), Eucalyptus ( Eucalyptus Tereticornis Sm.), poplar ( Populus Deltoides Marsh), and teak ( Tectona Grandis Linn. f.) forests in India. The results indicate that long-term total carbon storage ranges from 101 to 156 Mg C?ha ?1, with the largest carbon stock in the living biomass of long rotation sal forests (82 Mg C?ha ?1). The net annual carbon sequestration rates were achieved for fast growing short rotation poplar (8 Mg C?ha ?1?yr ?1) and Eucalyptus (6 Mg C?ha ?1?yr ?1) plantations followed by moderate growing teak forests (2 Mg C?ha ?1?yr ?1) and slow growing long rotation sal forests (1 Mg C?ha ?1?yr ?1). Due to fast growth rate and adaptability to a range of environments, short rotation plantations, in addition to carbon storage rapidly produce biomass for energy and contribute to reduced greenhouse gas emissions. We also used the model to evaluate the effect of changing rotation length and thinning regime on carbon stocks of forest ecosystem (trees?+?soil) and wood products, respectively for sal and teak forests. The carbon stock in soil and products was less sensitive than carbon stock of trees to the change in rotation length. Extending rotation length from the recommended 120 to 150 years increased the average carbon stock of forest ecosystem (trees?+?soil) by 12%. The net primary productivity was highest (3.7 Mg ha ?1?yr ?1) when a 60-year rotation length was applied but decreased with increasing rotation length (e.g., 1.7 Mg ha ?1?yr ?1) at 150 years. Goal of maximum carbon storage and production of more valuable saw logs can be achieved from longer rotation lengths. ‘No thinning’ has the largest biomass, but from an economical perspective, there will be no wood available from thinning operations to replace fossil fuel for bioenergy and to the pulp industry and such patches have high risks of forest fires, insects etc. Extended rotation lengths and reduced thinning intensity could enhance the long-term capacity of forest ecosystems to sequester carbon. While accounting for effects of climate change, a combination of bioenergy and carbon sequestration will be best to mitigation of CO 2 emission in the long term. 相似文献
9.
With the increasing use of tropical peatland for agricultural development, documentation of the rate of carbon dioxide (CO 2) emissions is becoming important for national greenhouse gas inventories. The objective of this study was to evaluate soil-surface CO 2 fluxes from drained peat under different land-use systems in Riau and Jambi Provinces, Sumatra, Indonesia. Increase of CO 2 concentration was tracked in measurement chambers using an Infrared Gas Analyzer (IRGA, LI-COR 820 model). The results showed that CO 2 flux under oil palm ( Elaeis guineensis) plantations ranged from 34?±?16 and 45?±?25 Mg CO 2 ha –1 year –1 in two locations in Jambi province to 66?±?25 Mg CO 2 ha –1 year –1 for a site in Riau. For adjacent plots within 3.2 km in the Kampar Peninsula, Riau, CO 2 fluxes from an oil palm plantation, an Acacia plantation, a secondary forest and a rubber plantation were 66?±?25, 59?±?19, 61?±?25, 52?±?17 Mg ha –1 year –1, respectively, while on bare land sites it was between 56?±?30 and 67?±?24 Mg CO 2 ha –1 year –1, indicating no significant differences among the different land-use systems in the same landscape. Unexplained site variation seems to dominate over land use in influencing CO 2 flux. CO 2 fluxes varied with time of day ( p?<?0.001) with the noon flux as the highest, suggesting an overestimate of the mean flux values with the absence of night-time measurements. In general, CO 2 flux increased with the depth of water table, suggesting the importance of keeping the peat as wet as possible. 相似文献
10.
New York City’s extensive municipal park system is home to forests, wetlands, and grasslands that provide important ecological and social benefits to the city’s population. While efforts and programs exist to restore and protect these spaces, management recommendations are complex due to variable conditions in urban natural areas. To advance the management of urban natural areas, the first comprehensive ecological assessment was conducted through a collaborative effort across 4000 ha of natural areas within New York City parkland. Field and spatial data were collected and analyzed to identify the extent of forests, the types of forests, and their conditions. This approach will help guide decision-making and prioritization of natural area management at the regional level by developing unique quantitative targets for urban forests. This project serves as an example of collaboration between private and public institutions advancing the governance of urban natural areas to achieve citywide conservation and policy goals. 相似文献
11.
Birds are the most diverse vertebrate group in Chile, characterized by low species turnover at the country-size scale (high alpha but low beta diversities), resembling an island biota. We tested whether this low differentiation is valid at a local scale, among six forest habitat types. We detected 25 bird species; avifauna composition was significantly different among habitat types, with five species accounting for 60 % of the dissimilarity. We found a higher level of bird assemblage differentiation across habitats at the local scale than has been found at the country-size scale. Such differentiation might be attributed to structural differences among habitats. 相似文献
12.
Restoration of deforested and drained tropical peat swamp forests is globally relevant in the context of reducing emissions from deforestation and forest degradation. The seasonal flux of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) in a restoration concession in Central Kalimantan, Indonesia, was measured in the two contrasting land covers: shrubs and secondary forests growing on peatlands. We found that land covers had high, but insignificantly different, soil carbon stocks of 949?+?56 and 1126?+?147 Mg ha?1, respectively. The mean annual CO2 flux from the soil of shrub areas was 52.4?±?4.1 Mg ha?1 year?1, and from secondary peat swamp forests was 42.9?±?3.6 Mg ha?1 year?1. The significant difference in mean soil temperature in the shrubs (31.2 °C) and secondary peat swamp forests (26.3 °C) was responsible for the difference in total CO2 fluxes of these sites. We also found the mean annual total soil respiration was almost equally partitioned between heterotrophic respiration (20.8?+?1.3 Mg ha?1 year?1) and autotrophic respiration (22.6?+?1.5 Mg ha?1 year?1). Lowered ground water level up to ??40 cm in both land covers caused the increase of CO2 fluxes to 40–75%. These numbers contribute to the provision of emission factors for rewetted organic soils required in the national reporting using the 2013 Supplement of the 2006 Intergovernmental Panel on Climate Change (IPCC) Guidelines for wetlands as part of the obligation under the United Nations Framework Convention on Climate Change (UNFCCC). 相似文献
13.
Leaf litterfall plays an important role in transporting atmospheric mercury to soil in forests area. 相似文献
14.
The objective of this study was to develop linear and nonlinear statistical models to predict enteric methane emission (EME) from cattle (Bos) in the tropics based on dietary and animal characteristic variables. A database from 35 publications, which included 142 mean observations of EME measured on 830 cattle, was constructed to develop EME prediction models. Several extant equations of EME developed for North American and European cattle were also evaluated for suitability of those equations in this dataset. The average feed intake and methane production were 7.7?±?0.34 kg/day and 7.99?±?0.39 MJ/day, respectively. The simple linear equation that predicted EME with high precision and accuracy was: methane (MJ/day)?=?1.29 (±0.906)?+?0.878 (±0.125)?×?dry matter intake (DMI, kg/day), [root mean square prediction error (RMSPE)?=?31.0 % with 92 % of RMSPE being random error; R 2?=?0.70]. Multiple regression equation that predicted methane production slightly better than simple prediction equations was: methane (MJ/day)?=?0.910 (±0.746)?+?1.472 (±0.154)?×?DMI (kg/day) – 1.388 (±0.451)?×?feeding level as a multiple of maintenace energy intake – 0.669 (±0.338)?×?acid detergent fiber intake (kg/day), [RMSPE?=?22.2 %, with 99.6 % of MSPE from random error; R 2?=?0.84]. Among the nonlinear equations developed, Mitscherlich model, i.e., methane (MJ/day)?=?71.47 (±22.14.6)?×?(1 - exp{?0.0156 (±0.0051)?×?DMI (kg/day), [RMSPE?=?30.3 %, with 97.6 % of RMSPE from random error; R 2?=?0.83] performed better than simple linear and other nonlinear models, but the predictability and goodness of fits of the equation did not improve compared with the multiple regression models. Extant equations overestimated EME, and many extant models had low accuracy and precision. The equations developed in this study will be useful for improved estimates of national methane inventory preparation and for a better understanding of dietary factors influencing EME for tropical cattle feeding systems. 相似文献
15.
Each of the last three decades has seen the Earth’s surface get progressively warmer more than any preceding decade since the 1850s. Greenhouse gas emissions from human activities have been scientifically demonstrated as the primary cause of the observed global climate change. The reduction of greenhouse gas levels in the atmosphere has deserved international attention. Aside from strategies to reduce emissions, increasing carbon storage by restoring and protecting destroyed forests has become an alternative method to lower carbon dioxide (CO 2) levels. Therefore, effective restoration/conservation plans for deforested lands are urgently needed. The current work focuses on the restoration and conservation potential of destroyed Qinghai spruce ( Picea crassifolia) forests in the Qilian Mountains of northwest China and provides a reasonable approach for drafting effective restoration/conservation plans for deforested lands. We first estimated habitat suitability of the Qinghai spruce using a habitat suitability model based on the relationships among the three most influential/significant environmental variables: average annual precipitation ( P), average air temperature in July ( T), and solar radiation ( R) and the corresponding occurrence frequency of Qinghai spruce in the niche space. We then calculated the index of habitat suitability ( IHS) for Qinghai spruce by applying a model in the study area. We finally used field data to classify the IHS map and identified the prior restoration and conservation areas for Qinghai spruce. The results show that (1) the optimal combination of T, P, and R for Qinghai spruce is 11.5 °C, 380 mm, and 2?×?10 3 kWh/m 2, respectively; (2) these forests have potential for restoration; (3) areas with priority restoration and conservation potential are about 43 and 56.65 km 2. The results of this study will help decision-makers develop and implement effective restoration/conservation strategies in the Qilian Mountains. This study presents a useful approach for helping decision-makers in other regions of the world draft effective restoration/conservation plans for deforested lands. The implementation of these plans will reduce CO 2 concentration in the atmosphere, in turn, may retard global warming. 相似文献
16.
Understanding atmospheric mercury (Hg) accumulation in remote montane forests is critical to assess the Hg ecological risk to wildlife and human health. To quantify impacts of vegetation, climatic and topographic factors on Hg accumulation in montane forests, we assessed the Hg distribution and stoichiometric relations among Hg, carbon (C), and nitrogen (N) in four forest types along the elevation of Mt. Gongga. Our results show that Hg concentration in plant tissues follows the descending order of litter > leaf, bark > root > branch > bole wood, indicating the importance of atmospheric Hg uptake by foliage for Hg accumulation in plants. The foliar Hg/C (from 237.0 ± 171.4 to 56.8 ± 27.7 µg/kg) and Hg/N (from 7.5 ± 3.9 to 2.5 ± 1.2 mg/kg) both decrease along the elevation. These elevation gradients are caused by the heterogeneity of vegetation uptake of atmospheric Hg and the variation of atmospheric Hg° concentrations at different altitudes. Organic soil Hg accumulation is controlled by forest types, topographic and climatic factors, with the highest concentration in the mixed forest (244.9 ± 55.7 µg/kg) and the lowest value in the alpine forest (151.9 ± 44.5 µg/kg). Further analysis suggests that soil Hg is positively correlated to C ( r2 = 0.66) and N ( r2 = 0.57), and Hg/C and Hg/N both increase with the soil depth. These stoichiometric relations highlight the combined effects from environmental and climatic factors which mediating legacy Hg accumulation and selective Hg absorption during processes of organic soil mineralization. 相似文献
17.
湿地植物多样性反映着湿地生态环境状况,并对维持湿地生态系统功能和服务至关重要.为掌握北京市湿地植物多样性现状并评估湿地生态质量状况,对北京市22处湿地植物多样性进行了调查,并结合遥感数据,从湿地植物的生境状况、物种多样性、群落典型性和外来种侵入度等4个方面建立指标开展评估,并分析生态环境因子和人类活动因子对湿地植物物种... 相似文献
18.
Measured carbon dioxide (CO 2) flux from peat soils using the closed chamber technique combines root-related (autotrophic + heterotrophic where rhizosphere organisms are involved) and peat-based (heterotrophic) respiration. The latter contributes to peat loss while the former is linked to recent CO 2 removal through photosynthesis. The objective of this study was to separate root- from peat-based respiration. The study was conducted on peatland under 6 and 15 year old oil palm ( Elaeis guineensis Jacq.) plantations in Jambi Province, Indonesia in 2011 to 2012. CO 2 emissions were measured in the field from 25 cm diameter and 25 cm tall closed chambers using an infrared gas analyser. Root sampling and CO 2 emissions measurements were at distances of 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, and 4.5 m from the centre of the base of the palm tree. The emission rate for the six and 15 year old oil palm plantations at ≥3.0 m from the centre of the tree were 38.2?±?9.5 and 34.1?±?15.9 Mg CO 2 ha ?1 yr ?1, respectively. At distances <2.5 m, total respiration linearly decreased with distances from the trees. Heterotrophic respirations were 86 % of the 44.7?±?11.2 and 71 % of 47.8?±?21.3 Mg CO 2 ha ?1 yr ?1 of weighted surface flux, respectively for the 6 and 15 year old plantations. We propose that CO 2 flux measurements in oil palm plantations made at a distance of ≥3 m from the tree centre be used to represent the heterotrophic respiration that is relevant for the environmental impact assessment. 相似文献
19.
Old growth mangroves in existing protected areas store more carbon than restored forests or plantations. Carbon storage in such forests has economic value independent of additionality, offering opportunities for policy makers to ensure their maintenance, and inclusion in climate change mitigation strategies. Mangrove forests of the Everglades National Park (ENP), South Florida, though protected, face external stressors such as hydrological alterations because of flooding control structures and agriculture impacts and saltwater intrusion as a result of increasing sea level rise. Moreover, decreased funding of Everglades’ restoration activities following the recent economic crisis (beginning 2008) threatens the restoration of the Greater Everglades including mangrove dominated coastal regions. We evaluate several economic and ecological challenges confronting the economic valuation of total (vegetation plus soil) organic carbon (TOC) storage in the ENP mangroves. Estimated TOC storage for this forested wetland ranges from 70 to 537 Mg C/ha and is higher than values reported for tropical, boreal, and temperate forests. We calculate the average abatement cost of C specific for ENP mangroves to value the TOC from $2–$3.4 billion; estimated unit area values are $13,859/ha–$23,728/ha. The valuation of the stored/legacy carbon is based on the: 1) ecogeomorphic attributes, 2) regional socio-economic milieu, and 3) status of the ENP mangroves as a protected area. The assessment of C storage estimates and its economic value can change public perception about how this regulating ecosystem service of ENP mangrove wetlands (144,447 ha) supports human well-being and numerous economic activities. This perception, in turn, can contribute to future policy changes such that the ENP mangroves, the largest mangrove area in the continental USA, can be included as a potential alternative in climate change mitigation strategies. 相似文献
20.
Buffalo River is an important water resource in the Eastern Cape Province of South Africa. Over a 1-year period (August 2010?CJuly 2011), we assessed the prevalence of human adenoviruses (HAdVs) at a total of 6 sites on the river and three dams along its course. HAdVs were detected by real-time quantitative PCR in about 35?% of the samples with concentrations ranging from 1.2?×?10 1 genome copies (GC)/l to 4.71?×?10 3 GC/l. HAdVs were detected at 5 of the 6 sampling sites with the detection rate ranging from 8.3?% at Rooikrantz Dam to 92?% at Parkside. The HAdV concentrations across the sampling sites were as follows: Parkside (3.25?×?10 2?C4.71?×?10 3?GC/); King William??s Town (1.02?×?10 2?C4.56?×?10 3?GC/l); and Eluxolzweni (1.17?×?10 2?C3.97?×?10 2 GC/l). Significantly ( P?<?0.05) higher concentrations were detected at the non-dam sites compared to the dam sites. A very low mean concentration of 1.86?×?10 1 HAdV GC/l was observed at Bridle Drift Dam. While HAdVs were detected only once at Rooikrantz Dam (1.74?×?10 1?GC/l), no HAdV was detected at Maden Dam. Epidemiologically important serotypes, Ad40/41, constituted 83.3?%, while Ad21 made up 16.7?% of the all HAdVs detected and were characterized by qualitative PCR. The Buffalo River presents a public health risk heightened by the presence of Ad 40/41 and Ad21. Our results make imperative the need for assessing water sources for viral contamination in the interest of public health. This work is a significant contribution to the molecular epidemiology of adenoviruses and to the best of our knowledge this is the first report on detection of enteric virus from surface waters in the Eastern Cape. 相似文献
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