Spatial Variations in the Distribution of Benthic Macroinvertebrate Functional Feeding Groups in Tropical Rivers

Functional feeding group (FFG) is an approach that classifies macroinvertebrates based on their utilization of organic matter food resources. Across streams and rivers, variations in the distribution of FFGs reflect the unequal distribution of food resources, which are affected by varying environmental conditions and disturbances to the ecosystem. In the tropics, the distribution of FFGs does not follow the pattern observed in temperate streams. This study aims to (1) determine the FFGs present in selected Philippine tropical streams, (2) assess the variations in FFG distributions and how the distributions vary across space, and (3) evaluate how FFG distributions are affected by certain environmental factors and habitat structure. Benthic macroinvertebrates were collected in 2010 from five sites and assigned to their primary FFG based on published literature. Across study sites, the macroinvertebrates collected were classified into gathering collectors (total n = 4,640), scrapers (n = 1,670), filtering collectors (n = 1,545), predators (n = 632), and shredders (n = 270). Within and between sites, these FFGs varied significantly. Variations explained the upstream-downstream and north-south variations in the mean of FFG abundance in width and depth of the stream, discharge, temperature, pH, riparian vegetation, and habitat stability and variability. This study reveals that the FFG approach is a useful bioassessment tool in tropical aquatic systems. However, there is still a need for verification of the findings in other streams and seasons.

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The composition of milk of British Alpine and Anglo–Nubian goats imported into Trinidad

Journal of Dairy Research ◽

10.1017/s0022029900014217 ◽

1972 ◽

Vol 39 (3) ◽

pp. 381-385 ◽

Cited By ~ 27

Author(s):

C. Devendra

Keyword(s):

Milk Composition ◽

Pennisetum Purpureum ◽

Dairy Goats ◽

Mineral Contents ◽

Total N ◽

Total Solids ◽

Concentrate Mixture ◽

The Mean ◽

Inadequate Nutrition ◽

The Tropics

SummaryThe variations in the composition of milk over an 18-week period from lactating British Alpine and Anglo–Nubian goats imported into Trinidad are reported. The animals were fed Napier grass (Pennisetum purpureum) ad lib. and 2 lb of a proprietary concentrate mixture daily.The mean percentage contents of the milks of British Alpine and Anglo–Nubian goats were: total solids 11·49±0·22, 12·17±0·28; butterfat 3·42±0·18, 4·06±0·22; total N 0·462±0·04, 0·530±0·07; ash 0·78±0·02, 0·79±0·03 and ‘lactose’ 4·38±0·28, 4·05±0·55. Anglo–Nubian goats had a higher content of percentage total solids, fat, total N and ash. For all constituents the coefficient of variation between weeks was higher for Anglo–Nubian goats. No significant trends were found between weeks for each of the components analysed for both breeds. Statistically significant correlations (P < 0·01) were found between percentage fat and percentage total N for both breeds.The mean mineral contents (mg/100ml) for the milks of British Alpine and Anglo–Nubian goats were: Na 52·6±4·6, 55·5±1·9; K164·0±8·4, 133·4±11·4; Ca 85·5±11·6, 89·9±9·8; Mg 13·2±3·8, 10·2±1·6 and P 74·7±3·9, 82·1±3·9. British Alpine goat's milk had a higher content of K and that of Anglo–Nubian goats had a higher content of P; both differences were statistically significant (P < 0·01).The milk composition figures in this study together with those from a similar study in Guadeloupe suggest that the values are low and considerably lower in comparison with the same breeds of goats in a temperate environment. This could be a feature of dairy goats imported into the tropics due perhaps to inadequate nutrition. Much more information is needed to verify this possibility.

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Potential Fertilization Capacity of Two Grapevine Varieties: Effects on Agricultural Production in Designation of Origin Areas in the Northwestern Iberian Peninsula

Agronomy ◽

10.3390/agronomy10070961 ◽

2020 ◽

Vol 10 (7) ◽

pp. 961

Author(s):

J. Antonio Cortiñas Rodríguez ◽

María Fernández-González ◽

Estefanía González-Fernández ◽

Rosa A. Vázquez-Ruiz ◽

F. Javier Rodríguez-Rajo ◽

...

Keyword(s):

Airborne Pollen ◽

Germination Rate ◽

Pollen Viability ◽

Weather Conditions ◽

Triphenyl Tetrazolium Chloride ◽

Tetrazolium Chloride ◽

The Mean ◽

Study Sites ◽

Fertilization Capacity

In the present study, we analyzed the main parameters related with the potential fertilization ability of two grapevine varieties, Godello and Mencía, during the years 2017 and 2018. The research was carried out in two vineyards of the Galician winegrowing Designation of Origin areas of Ribeiro and Ribeira Sacra. Ten vines of each variety were selected for bunch and flower counting, pollen calculations, pollen viability studies by means of aceto-carmine (AC) stain and 2, 3, 5-triphenyl tetrazolium chloride (TTC) methods, and the determination of their germination rate. In all vineyards the 50% fruitset was reached, except for Godello in Cenlle during 2017. The mean coulure value was higher for Godello (40.5%) than for Mencía (31%). Analyzing the pollen production per plant and airborne pollen levels, we observed important discordances between them, which can be due to the influence of weather conditions and be related with self-pollination processes. We found important differences on pollen viability depending on the applied method and variety, with higher values for the AC method than the TTC for both varieties in all study plots, and higher values for Mencía variety than Godello. Regarding germination rates, we observed a marked reduction in 2017 with respect to 2018, in all study sites and for both varieties. The analyzed parameters were useful to explain the different productive abilities of Godello and Mencía varieties in the two studied bioclimatic regions of Ribeiro and Ribeira Sacra.

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Growth and N status of Populus in mixture with red alder on recent volcanic mudflow from Mount Saint Helens

Canadian Journal of Forest Research ◽

10.1139/x90-012 ◽

1990 ◽

Vol 20 (1) ◽

pp. 84-90 ◽

Cited By ~ 5

Author(s):

Paul E. Heilman

Keyword(s):

Late Summer ◽

Height Growth ◽

Phosphorus Fertilization ◽

Cross Sectional ◽

Red Alder ◽

Total N ◽

Foliar N ◽

N Concentration ◽

The Mean ◽

Foliar N Concentration

Eleven months after the May 1980 eruption of Mount Saint Helens in southeastern Washington, United States, three Populus clones were planted in an experiment on the Toutle River mudflow deposit. The trees grew at an abnormally slow rate and by 3 years were overtopped by a dense stand (14 600 ± 3600 trees/ha) of red alder seeded naturally onto the site. Over the 6-year period of the study, the total N content of the soil increased an average of 56 kg•ha−1•year−1•. Foliar N concentration in Populus increased significantly from a mean late summer – early autumn value in the 2nd year (1982) of 0.69% N to a value of 2.06% N at the end of the seventh growing season. The mean annual height growth of the largest Populus averaged <0.5 m/year in the first 3 years, increasing to an average of over 1.0 m/year in the 5th and 6th years. Fertilizer treatments with N (as urea) and N + P (as urea plus treble superphosphate) placed in the soil near the individual Populus at a maximum rate of 5.3 g N/tree increased height growth in the year of fertilization (1982) and the following year (the response in height growth for the 2 years totaled 64%). After 1984, no significant effects of fertilizer on height growth, total height, or diameter were evident. Nitrogen fertilization significantly increased foliar N concentration (1.54% N with the highest N treatment vs. 0.69% N in the control) in the year of treatment only. Phosphorus fertilization had no significant effect on growth or foliar P concentration. At 6 years, only 2% of the Populustrichocarpa Torr. & Gray clone and 13% of the tallest Populus hybrid were equal to or above the mean height of alder dominants and codominants (6.2 m). Additionally, the diameter growth of Populus was severely limited: the trees had only 8% of the cross-sectional area of "normal" trees for their height. Results indicated that on sites of low N such as the mudflow, Populus may not compete satisfactorily in mixture with alder. Such behavior is in sharp contrast to sites of high N, where red alder cannot compete with Populus.

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Resource Utilization and Costs of Care prior to ART Initiation for Pediatric Patients in Zambia

AIDS Research and Treatment ◽

10.1155/2014/235483 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Hari S. Iyer ◽

Callie A. Scott ◽

Deophine Lembela Bwalya ◽

Gesine Meyer-Rath ◽

Crispin Moyo ◽

...

Keyword(s):

Pediatric Patients ◽

Blood Chemistry ◽

Full Blood Count ◽

National Guidelines ◽

Art Initiation ◽

Time To Initiation ◽

The Mean ◽

Study Sites ◽

Cd4 Percentage ◽

Mean Cost

Objective. We estimated time to initiation, outpatient resource use, and costs of outpatient care during the 6 months prior to ART initiation for HIV-infected pediatric patients in Zambia.Methods. We enrolled 1,102 children who initiated ART at <15 years of age between 2006 and 2011 at 5 study sites. Of these, 832 initiated ART ≤6 months after first presenting to care at the study sites. Data on time in care and resources utilized during the 6 months prior to ART initiation were extracted from patient medical records. Costs were estimated from the provider’s perspective and are reported in 2011 USD.Results. For the patients who initiated ART ≤6 months after presenting to care, median age at presentation to care was 3.9 years; median CD4 percentage was 13%. Median time to ART initiation was 26 days. Patients made, on average, 2.38 clinic visits prior to ART initiation and received 0.81 CD4 tests, 0.74 full blood count tests, and 0.49 blood chemistry tests. The mean cost of pre-ART care was $20 per patient.Conclusions. Zambian pediatric patients initiating ART ≤6 months after presenting to care do so quickly, utilize fewer resources than mandated by national guidelines, and accrue low costs.

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Residual effects of nitrogen fertiliser on the yield and N composition of succeeding cereal crops and on soil chemical properties of an Ethiopian highland Vertisol

Canadian Journal of Soil Science ◽

10.4141/s99-008 ◽

2000 ◽

Vol 80 (1) ◽

pp. 63-69 ◽

Cited By ~ 7

Author(s):

Selamyihun Kidanu ◽

D. G. Tanner ◽

Tekalign Mamo

Keyword(s):

N Uptake ◽

Chemical Properties ◽

Residual Effect ◽

Residual Effects ◽

Cereal Crops ◽

N Recovery ◽

N Application ◽

Total N ◽

Current Season ◽

The Mean

A trial was conducted on an Ethiopian Vertisol from 1990 to 1995 to determine the residual effects of fertiliser N applied to tef [Eragrostistef (Zucc.) Trotter] on the grain and straw yield, N content, and total N uptake of succeeding crops of durum wheat (Triticum turgidum var. durum) and tef. The mean agronomic efficiency of 60 kg fertiliser N ha−1 was 13.1 kg grain kg−1 fertiliser N applied in the current year and 5.4 kg grain kg−1 fertiliser N applied in the previous year. Thus, the residual fertiliser N benefit was equivalent to 41.2% of the response to current season N application for the two cereal crops. The mean rates of apparent recovery of fertiliser N were 65.8% for current season N application and 31.0% for previous season N application. Soil organic matter and nitrate levels increased linearly in response to both previous and current season N application rates. The current study demonstrates that the residual effect of fertiliser N enhanced the yields and N contents of the grain and straw of both wheat and tef, resulting in a significant increase in total N uptake. Any analysis of the profitability of fertiliser N response should reflect the multi-year benefit period. Key words: N recovery, N residue, N uptake, tef, wheat

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Functional feeding groups of Protist Ciliates (Protist: Ciliophora) on a neotropical flood plain

Annales de Limnologie - International Journal of Limnology ◽

10.1051/limn/2021009 ◽

2021 ◽

Vol 57 ◽

pp. 13

Author(s):

Bianca Ramos Meira ◽

Melissa Progênio ◽

Edilaine Corrêa Leite ◽

Fernando Miranda Lansac-Tôha ◽

Carolina Leite Guimarães Durán ◽

...

Keyword(s):

Flood Plain ◽

Food Resources ◽

Functional Feeding Groups ◽

Hydrodynamic Conditions ◽

Efficient Tool ◽

Ecological Processes ◽

Clear Separation ◽

Feeding Groups ◽

Temporal Segregation ◽

Influence Of Food

Functional diversity approaches have been an efficient tool in gaining a better understanding of how environmental conditions selected species in a given environment and how they share resources, linking ecological processes to biodiversity patterns. Although most of the protist ciliates are not highly specialized, functional feeding groups with species which ingest similar food can be identified. Thus, this study aimed to compare the abundance of different Functional Feeding Groups (FFG) of ciliates in environments with different hydrodynamic conditions (lotic and lentic) in different hydrological periods (high and low water) in a neotropical flood plain. The samples for analysis of the community of ciliates were taken in March and September of 2010 and 2011, at the subsurface of 12 different hydrodynamic environments. The results of an RDA showed a spatial and temporal segregation of the sampling units, based on the abundance and occurrence of the FFG. In addition, a clear influence of food resources on the structuring of functional ciliate guilds was evidenced. Thus, there were both temporal (hydrological periods) and spatial (different hydrodynamic environments) differences in the distribution of the FFG, with a clear separation of the FFGs between the years studied. In summary, the results of the categorization of species of ciliates in FFG responded satisfactorily suggesting fluctuations in different food resources, which reinforces the idea that the grouping of species by functional characteristics can be a good indicator of the responses of organisms to environmental fluctuations.

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Assessing the sustainability of yellow anaconda (Eunectes notaeus) harvest in northeastern Argentina

10.21203/rs.3.rs-109402/v1 ◽

2020 ◽

Author(s):

Bruno Camera ◽

Christine Stüssmann ◽

Itxaso Quintana ◽

Tomás Waller ◽

Mariano Barros ◽

...

Keyword(s):

Wildlife Management ◽

Sustainable Use ◽

Management Program ◽

Gradual Reduction ◽

Hunting Season ◽

Time Period ◽

History Of ◽

The Mean ◽

The Tropics ◽

Northeastern Argentina

Abstract Sustainable wildlife management is required to guarantee source species viability; however, it is practiced rarely in the tropics. The yellow anaconda (Eunectes notaeus) has a long history of being harvested for its leather. Since 2002 its harvest has operated under a management program in northeastern Argentina, which relies on adaptive management through limiting the minimum anaconda length, number of hunters and restricting the hunting season. We investigated the effects of the anaconda harvest on its biological parameters based on 2002-2016 data. Here we show that the levels of species exploitation are sustainable. The gradual reduction in the annual hunting effort, due to a decrease in number of hunters and hunting season duration, reduced the total number of anacondas harvested. Conversely, captures per unit effort increased across the study time-period. There was no variation in the mean length of anacondas harvested, or in largest anaconda sizes. Though more females than males were caught, the sex ratio did not vary significantly. We also found that a decrease in mean temperature positively influenced anaconda harvest and the captures of giant individuals. Because sustainable use is a powerful tool for conservation, those discoveries are highly applicable to other species and regions.

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Variability and quasi-decadal changes in the methane budget over the period 2000–2012

10.5194/acp-2017-296 ◽

2017 ◽

Cited By ~ 2

Author(s):

Marielle Saunois ◽

Philippe Bousquet ◽

Benjamin Poulter ◽

Anna Peregon ◽

Philippe Ciais ◽

...

Keyword(s):

Biomass Burning ◽

Methane Emissions ◽

Data Driven ◽

Atmospheric Methane ◽

Top Down ◽

Bottom Up ◽

Ch4 Emissions ◽

Ensemble Mean ◽

The Mean ◽

The Tropics

Abstract. Following the recent Global Carbon project (GCP) synthesis of the decadal methane (CH4) budget over 2000–2012 (Saunois et al., 2016), we analyse here the same dataset with a focus on quasi-decadal and inter-annual variability in CH4 emissions. The GCP dataset integrates results from top-down studies (exploiting atmospheric observations within an atmospheric inverse-modelling frameworks) and bottom-up models, inventories, and data-driven approaches (including process-based models for estimating land surface emissions and atmospheric chemistry, inventories of anthropogenic emissions, and data-driven extrapolations). The annual global methane emissions from top-down studies, which by construction match the observed methane growth rate within their uncertainties, all show an increase in total methane emissions over the period 2000–2012, but this increase is not linear over the 13 years. Despite differences between individual studies, the mean emission anomaly of the top-down ensemble shows no significant trend in total methane emissions over the period 2000–2006, during the plateau of atmospheric methane mole fractions, and also over the period 2008–2012, during the renewed atmospheric methane increase. However, the top-down ensemble mean produces an emission shift between 2006 and 2008, leading to 22 [16–32] Tg CH4 yr−1 higher methane emissions over the period 2008–2012 compared to 2002–2006. This emission increase mostly originated from the tropics with a smaller contribution from mid-latitudes and no significant change from boreal regions. The regional contributions remain uncertain in top-down studies. Tropical South America and South and East Asia seems to contribute the most to the emission increase in the tropics. However, these two regions have only limited atmospheric measurements and remain therefore poorly constrained. The sectorial partitioning of this emission increase between the periods 2002–2006 and 2008–2012 differs from one atmospheric inversion study to another. However, all top-down studies suggest smaller changes in fossil fuel emissions (from oil, gas, and coal industries) compared to the mean of the bottom-up inventories included in this study. This difference is partly driven by a smaller emission change in China from the top-down studies compared to the estimate in the EDGARv4.2 inventory, which should be revised to smaller values in a near future. Though the sectorial partitioning of six individual top-down studies out of eight are not consistent with the observed change in atmospheric 13CH4, the partitioning derived from the ensemble mean is consistent with this isotopic constraint. At the global scale, the top-down ensemble mean suggests that, the dominant contribution to the resumed atmospheric CH4 growth after 2006 comes from microbial sources (more from agriculture and waste sectors than from natural wetlands), with an uncertain but smaller contribution from fossil CH4 emissions. Besides, a decrease in biomass burning emissions (in agreement with the biomass burning emission databases) makes the balance of sources consistent with atmospheric 13CH4 observations. The methane loss (in particular through OH oxidation) has not been investigated in detail in this study, although it may play a significant role in the recent atmospheric methane changes.

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2019 IFFAS Award for Excellence Winner: Peri-Prosthetic Cysts and Alignment in Total Ankle Replacement: A 3-D, Weight Bearing Topographical Study

Foot & Ankle Orthopaedics ◽

10.1177/2473011419s00049 ◽

2019 ◽

Vol 4 (4) ◽

pp. 2473011419S0004

Author(s):

Francois Lintz ◽

Jef Mast ◽

Nazim Mehdi ◽

Alessio Bernasconi ◽

Cesar de Cesar Netto ◽

...

Keyword(s):

Weight Bearing ◽

Total Ankle Replacement ◽

Coronal Plane ◽

Unequal Distribution ◽

Hindfoot Alignment ◽

Cyst Volume ◽

Ankle Replacement ◽

The Mean ◽

The Difference

Category: Ankle, Ankle Arthritis Introduction/Purpose: Peri-prosthetic cysts (PPC) in Total Ankle Replacement (TAR) are a common failure cause but the mechanisms of their development remains unclear. One possible explanation could be hindfoot malalignment and subsequent unequal distribution of load inside the joint. However, how residual malalignment influences the evolution of PPC remains unclear. Computed tomography (CT) has demonstrated superiority on conventional radiography in the follow up of PPC. Weight Bearing CT (WBCT), by combining 3D imaging and weight bearing measurements seems a valid tool to investigate this further. The objective for this work was to study the effects of residual hindfoot deformity on the distribution of PPC in the coronal plane. We hypothesized that cysts would be found predominantly medially in varus configuration, and laterally in valgus configuration. Methods: Retrospective comparative study, ethics committee approved. Forty-eight cases of TAR were included, with relevant demographics. Inclusion criteria were cases of primary TAR with available WBCT imaging of their ankle as part of normal follow up. Exclusion criteria were subsequent implant revision or cyst grafting. In each case, the localization and size of PPC’s were documented and their volume calculated by approximation of the closest ellipsoid. Hindfoot alignment was evaluated by the percentage Foot Ankle Offset (FAO) (foot-length normalized 3D ratio between the midline of the foot and the center of the ankle) using a WBCT dedicated semi-automatic software. The mean FAO value with 95%CI for the population was calculated. The difference in medial and lateral cyst volume defined by their position relative to the median axis in the coronal plane was compared in varus and valgus cases by a Mann-Whitney non-parametric test for unpaired samples. Results: Demographic distributions of the series were 32% female, mean age 65 (45-85) years. Mean FAO value was 0.12% (95%CI -1.09 to 1.33). Mean follow up was 43 months (6 to 239). The mean total cyst volume per case was 1190,7 mm3. In varus cases (defined by FAO<-1.09%), the volume of medial cysts was greater than laterally by a mean 197 mm3, whereas in valgus cases (defined by FAO>1.33%), the volume of lateral cysts was greater than medially by a mean 332 mm3. The difference was statistically significant (p<0.05). There was a weak, significant positive correlation (r=0.25, p<0,001) between FAO and total cyst volume and a moderate, significant correlation (r=0,56, p<0,001) between time to follow up and total cyst volume. Conclusion: Our hypothesis was confirmed. Periprosthetic cysts volume in this series of primary TAR was found to be relatively greater medially in postoperative varus configurations and vice-versa laterally in valgus. This confirms a possible correlation between the direction of residual hindfoot malalignment and the coronal localization of PPC in TAR, although this is certainly not the only pathophysiologic factor involved in PPC onset. Weightbearing CT may be helpful in Total Ankle Replacement follow up, in order to early detect PPC development and possibly to identify situations at risk of a more rapid evolution.

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Changing Microarthropod Communities in Front of a Receding Glacier in the High Arctic

Insects ◽

10.3390/insects11040226 ◽

2020 ◽

Vol 11 (4) ◽

pp. 226 ◽

Cited By ~ 5

Author(s):

Dariusz J. Gwiazdowicz ◽

Bogna Zawieja ◽

Izabella Olejniczak ◽

Piotr Skubała ◽

Anna K. Gdula ◽

...

Keyword(s):

Dominant Species ◽

Diversity Index ◽

Rapid Change ◽

High Arctic ◽

Soil Characteristics ◽

Landscape Scale ◽

Soil Samples ◽

Pioneer Species ◽

The Mean ◽

Study Sites

This study was carried out at Ny-Ålesund on Spitsbergen in Svalbard (High Arctic). Eight study sites were established along a transect from the fjord to the snout of the glacier. The sites differed from each other by the type of vegetation cover and soil characteristics. Soil samples were collected and placed in Tullgren funnels. Extracted arthropods were represented by two groups of mites (Mesostigmata and Oribatida) and springtails (Collembola). The pioneer species that occurred first after retreat of the glacier were representatives of the Collembola (Agrenia bidenticulata and Hypogastrura concolor). Later, other springtails appeared including Folsomia alpha, Folsomia quadrioculata, Hypogastrura concolor, Isotoma anglicana, Sminthurinus concolor and the first species of oribatid mites; Camisia foveolata and Tectocepheus velatus velatus. Arthropod communities recorded along the transect were characterized by large variations in both species composition and abundance of individuals. The greater the distance from the glacier snout, the greater the species richness (2 to 22 species). The mean number of species per sample was the lowest at site 8 (1 ± 0.71) (the closest to the glacier) and greatest at site 1 (14 ± 1.41) (furthest from the glacier). The Simpson’s diversity index (D) was distinctly greater at sites 1 (4.61 ± 0.06) and 3 (3.94 ± 0.11) than at other sites, especially site 8 (1.07 ± 0.06). Densities were least in the samples closest to the glacier (30 to 101 individuals; density 3000–10,100 individuals/m2). At the other locations, abundance was highly variable (905 to 7432 individuals; density 90,500–743,200 individuals/m2). The mean abundances were greatest at sites 2 and 3. The great variations in total abundances observed were often due to the presence or absence of one or more dominant species exhibiting extreme abundance variability between sites. The microarthropod community of the High Arctic is composed of heterogeneous circumpolar species, yet on a landscape scale is extremely dependent on local environmental conditions which may be subject to rapid change.

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