Remotely Sensed Changes in Vegetation Cover Distribution and Groundwater along the Lower Gila River

Introduced as a soil erosion deterrent, salt cedar has become a menace along riverbeds in the desert southwest. Salt cedar replaces native species, permanently altering the structure, composition, function, and natural processes of the landscape. Remote sensing technologies have the potential to monitor the level of invasion and its impacts on ecosystem services. In this research, we developed a species map by segmenting and classifying various species along a stretch of the Lower Gila River. We calculated metrics from high-resolution multispectral imagery and light detection and ranging (LiDAR) data to identify salt cedar, mesquite, and creosote. Analysts derived training and validation information from drone-acquired orthophotos to achieve an overall accuracy of 94%. It is clear from the results that salt cedar completely dominates the study area with small numbers of mesquite and creosote present. We also show that vegetation has declined in the study area over the last 25 years. We discuss how water usage may be influencing the plant health and biodiversity in the region. An examination of ground well, stream gauge, and Gravity Recovery and Climate Experiment (GRACE) groundwater storage data indicates a decline in water levels near the study area over the last 25 years.

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Estimating the Effects of Anthropogenic Modification on Water Balance in the Aral Sea Watershed Using GRACE: 2003–12

Earth Interactions ◽

10.1175/2013ei000537.1 ◽

2014 ◽

Vol 18 (3) ◽

pp. 1-16 ◽

Cited By ~ 16

Author(s):

Kirk Zmijewski ◽

Richard Becker

Keyword(s):

Water Balance ◽

Water Mass ◽

Gravity Data ◽

Water Levels ◽

Aral Sea ◽

Local Climate ◽

Global Precipitation Climatology Centre ◽

Negative Impacts ◽

Gravity Recovery ◽

Global Precipitation

Abstract The decrease in size the Aral Sea in central Asia, seen as both lower water levels and reduction in areal extent, has been one of the greatest examples of anthropogenic modification of a natural system in recent history. Many studies have monitored the extent and rate of this water loss and provided estimates on the expected life span of the remaining water. However, with little data for groundwater monitoring in the post-Soviet era, it is unclear what the water balance currently is in the remainder of the watershed. Redistribution of water upstream in the watershed including damming to create reservoirs and groundwater recharge from irrigation has not only deprived the sea of water but also increased evapotranspiration and altered local climate patterns. Using Tropical Rainfall Measurement Mission (TRMM) and Global Precipitation Climatology Centre (GPCC) data, rainfall trends for the Aral Sea watershed were analyzed over 10- and 30-yr periods and only minimal changes in rainfall were detected. Using Gravity Recovery and Climate Experiment (GRACE) gravity data from 2003 to 2012, trends in equivalent water mass were determined for the entire watershed. Estimates show up to 14 km3 of equivalent water mass has been lost from the watershed annually from 2002 to 2013. The mass loss throughout the basin is most likely attributable to increased evapotranspiration due to the inefficient irrigation systems and other human modification increasing the need for international cooperation and conservation programs to minimize negative impacts throughout the region.

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Statistical Analysis and Trend Detection of the Hydrological Extremes of the Danube River at Bratislava

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/906/1/012101 ◽

2021 ◽

Vol 906 (1) ◽

pp. 012101

Author(s):

Veronika Bacová Mitková

Keyword(s):

Statistical Analysis ◽

Anthropogenic Activities ◽

Water Levels ◽

Danube River ◽

Trend Detection ◽

The Danube River ◽

Natural Processes ◽

The Past ◽

Hydrological Extremes ◽

Measured Water

Abstract The territory of the Danube River Basin is one of the most flood-endangered regions in Europe. The flow regime conditions of the Danube River are continually changing. These changes are the result of natural processes and anthropogenic activities. In the present study, we focused on the statistical analysis and trend detection of the hydrological extremes of the Danube River at Bratislava. This paper firstly analyses the changes in correlation between water levels of the Danube River at Bratislava and Kienstock. Studied period of 1991-2013 included one or three hour measured water levels of the Danube River at Bratislava and Kienstock and shorter periods (1991–1995, 1999–2002, and 2004—2013) were selected for identification of the water level changes at Bratislava. One of the factors that recall the necessity to establish empirical - regression relationships was increasing of water levels of the Danube River at Bratislava (due to sediments accumulation at Bratislava). The results of the analysis indicated an increasing of water levels corresponding to the same flood discharges observed in the past. We also can say that travel time of the Danube floods between Kienstock and Bratislava did not change significantly during the analysed period. In the second part of the paper, we have identified changes in commonly used hydrological characteristics of annual maximum discharges, annual discharges and daily discharges of the Danube River at Bratislava during the period of 1876–2019. We examined whether there is a significant trend in discharges of the Danube River at Bratislava.

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Using White Star (Nymphoides humboldtiana) for lake landscaping

Horticultura Brasileira ◽

10.1590/s0102-053620190202 ◽

2019 ◽

Vol 37 (2) ◽

pp. 133-137

Author(s):

Carla D Tedesco ◽

Claudia Petry ◽

Edson C Bortoluzzi ◽

Alfredo Castamann

Keyword(s):

Water Level ◽

Leaf Area ◽

Water Depth ◽

Native Species ◽

High Water ◽

Water Levels ◽

Vegetative Development ◽

High Water Level ◽

Number Of Leaves ◽

White Star

ABSTRACT White Star (Nymphoides humboldtiana), an aquatic-environmental native species of Brazilian flora, was selected in order to be used as ornamental plant in lakes. White Star plants were submitted to two water levels (high water level, up to 30 cm water depth and, low water level until substrate saturation) and two light intensities (full sun and 50% shading) to evaluate vegetative and flowering development. The experimental design was completely randomized, in a subplot scheme, being the water level the main plot and luminosity the subplot. Seven replicates were performed, and the sample unit consisted of one plant. Data related to number of leaves and flowers, length and diameter of petioles and leaf area were submitted to analyze of variance and regression. We observed an increase in number of leaves and flowers in the treatment of high water level in full sun, and an increase of petiole length in high water level with shading. No difference between leaf area of plants grown under full sun and with shading (p<0.05) was observed. At low water level, plants presented lower vegetative development than those grown at high water level, besides the flowering inhibition in shaded condition. These results demonstrated that White Star can be used in ornamental lakes with a water depth of at least 20 cm above the rhizome and exposed to full sun.

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Reproductive strategy and growth of the Australian smelt, Retropinna semoni (Weber) (Pisces : Retropinnidae), and the olive perchlet, Ambassis nigripinnis (De Vis) (Pisces : Ambassidae), in Brisbane, south-eastern Queensland

Marine and Freshwater Research ◽

10.1071/mf9850329 ◽

1985 ◽

Vol 36 (3) ◽

pp. 329 ◽

Cited By ~ 22

Author(s):

DA Milton ◽

AH Arthington

Keyword(s):

Native Species ◽

Juvenile Fish ◽

Open Water ◽

Water Levels ◽

South Eastern ◽

Large Populations ◽

Coastal Streams ◽

Littoral Vegetation ◽

Suitable Habitats ◽

Eggs And Larvae

The reproductive biology and growth of R. semoni and A. nigripinnis were studied in Brisbane, south- eastern Queensland, over a 20-month period (1981-1982). R. semoni began to breed in winter at water temperatures exceeding 15�C, reflecting its salmoniform affinities and temperate distribution. A. nigripinnis, a subtropical species of Indo-Pacific origin, required a period of rising temperature before breeding began in spring at 22�C. Both species concentrated their breeding activity into the months that precede summer storms and high, variable stream discharges, which can generate fluctuating water levels, destruction of weedbeds and instability of the stream substrate. Pre-flood spawning also occurs in three other small-bodied native species in the region, and appears to have adaptive value in the seasonally unstable environments of coastal streams. Dispersal of juvenile fish may be facilitated by rising water levels during summer months following spawning. R. semoni grew faster and to larger sizes than A. nigripinnis and growth of both species was adequately described by the von Bertalanffy equation. Male and female R. semoni and male A. nigripinnis live and breed for 2 years but female A. nigripinnis survive and may breed into their third year. These patterns of survivorship and reproduction are consistent with the contention that natural mortality is higher in open-water foragers such as R. semoni than in species like A. nigripinnis, which tends to forage amongst littoral vegetation and in mid-water. Differences in the sizes of eggs and larvae of the two species are also consistent with the probability that they experience different relative exposure to predation. These and other attributes, coupled with pre-flood spawning, enable both species to achieve large populations in suitable habitats within coastal streams, in spite of their relatively low fecundities.

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Historical Changes in Large River Fish Assemblages of the Americas

Historical Changes in Large River Fish Assemblages of the Americas ◽

10.47886/9781888569728.ch9 ◽

2005 ◽

Keyword(s):

New Mexico ◽

Native Species ◽

Colorado River ◽

Fish Assemblages ◽

Large River ◽

Main Stem ◽

Past Century ◽

The West ◽

Gila River ◽

Nonnative Fish

<em>Abstract.</em>—The Gila River originates in southwestern New Mexico and courses its way for over 700 km to the west before emptying into the main-stem Colorado River near Yuma, Arizona. Historically, this river was a major watercourse across the Sonora Desert of Arizona. At present, main-stem dams and numerous diversions have markedly altered the historic hydrology of the river. Seventeen native species once occupied the main stem of this large southwest desert river. More than twice that number (40) of nonnative fish species have been introduced into the waters of the Gila over the past century. Currently, less than half of the native fauna is present in the main stem and then primarily in the upper three reaches of the river. The majority of the species (70%) are federally listed as threatened, endangered, or sensitive. The combination of hydrological alteration and accompanying introductions of nonnative, principally sport fishes has basically extirpated the native fauna in all but the uppermost reaches of the Gila River main stem.

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Effect of Anthropogenic Disturbance on Floristic Homogenization in the Floodplain Landscape: Insights from the Taxonomic and Functional Perspectives

Forests ◽

10.3390/f11101036 ◽

2020 ◽

Vol 11 (10) ◽

pp. 1036

Author(s):

Yang Cao ◽

Yosihiro Natuhara

Keyword(s):

Environmental Factors ◽

Anthropogenic Disturbance ◽

Native Species ◽

Regional Scale ◽

Biotic Interactions ◽

Environmental Parameters ◽

Limited Information ◽

Natural Processes ◽

Β Diversity ◽

Floodplain Area

Anthropogenic disturbances pose significant threats to biodiversity. However, limited information has been acquired regarding the degree of impact human disturbance has on the β-diversity of plant assemblages, especially in threatened ecosystems (e.g., floodplains). In the present study, the effects of anthropogenic disturbance on plant communities of floodplain areas (the Miya River, Mie Prefecture, Japan) were analyzed. The taxonomic and functional β-diversity among different degradation levels were compared, and the differences were assessed by tests for homogeneity in multivariate dispersions. In addition, the effects of non-native species and environmental factors on β-diversity were analyzed. As revealed from the results, anthropogenic disturbance led to taxonomic homogenization at a regional scale. The increase in non-native invasions tended to improve homogenization, whereas at a low degradation level, the occurrence of non-natives species was usually related to taxonomic differentiation. Furthermore, though the increase in non-natives and environmental parameters significantly affected the β-diversity of the floodplain area, environmental factors may be of more crucial importance than biotic interactions in shaping species assemblages in this study. The previously mentioned result is likely to be dependent on the research scale and the extent to which floodplains are disturbed. Given the significant importance of floodplains, the significance of looking at floodplains in the different levels of degradation was highlighted, and both invasion of non-native species and environmental factors should be considered to gain insights into the response of ecosystems to anthropogenic disturbance. The findings of this study suggested that conservation programs in floodplain areas should place more emphasis on the preservation of natural processes and forest resources.

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The biology of Canadian weeds. 100. Lythrum salicaria

Canadian Journal of Plant Science ◽

10.4141/cjps92-164 ◽

1992 ◽

Vol 72 (4) ◽

pp. 1305-1330 ◽

Cited By ~ 78

Author(s):

Tarun R. Mai ◽

Jon Lovett-Doust ◽

Lesley Lovett-Doust ◽

G. A. Mulligan

Keyword(s):

Native Species ◽

Competitive Ability ◽

Lythrum Salicaria ◽

Water Levels ◽

Purple Loosestrife ◽

Low Density ◽

Biological Control Agents ◽

Extreme Sensitivity ◽

Root Buds ◽

Wetland Habitats

Lythrum salicaria is a serious weed of wetlands in Canada, particularly in Ontario and Quebec. Indeed some assessments suggest that this exotic is now responsible for the conversion of more wetland habitat than is current human development pressure¡ Lythrum is a heterostylous species and clones by means of root buds. Despite its tristylous breeding system, Lythrum is a successful colonizer, and can produce prodigious numbers of seeds. It is likely that control can be achieved by hand-pulling in low-density populations, but once the species is established it generally becomes abundant and often approaches a monoculture. This species is particularly difficult to control because of its strong competitive ability, the extreme sensitivity of wetland habitats, and the likelihood of serious repercussions for wetland wildlife and fisheries if herbicides are used to control it. We see better possibilities for control through cultural techniques (e.g., manipulation of water levels to favour native species), enhancement of North American herbivores, and, possibly, the introduction of biological control agents from Europe and Asia.Key words: Purple loosestrife, Lythrum salicaria, wetlands, introduced weed

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SUBSTRATES AND WATER AVAILABILITY ON THE EMERGENCE AND INITIAL GROWTH OF Alibertia sessilis Schum. SEEDLINGS

FLORESTA ◽

10.5380/rf.v47i4.53083 ◽

2017 ◽

Vol 47 (4) ◽

pp. 513 ◽

Cited By ~ 1

Author(s):

Leandro Henrique De Sousa Mota ◽

Silvana De Paula Quintão Scalon ◽

Rafael Heinz ◽

Daiane Mugnol Dresch

Keyword(s):

Water Availability ◽

Native Species ◽

Slow Growth ◽

Poultry Litter ◽

Water Levels ◽

Initial Growth ◽

Emergence Percentage ◽

Red Latosol ◽

Water Holding

The cultivation of native species in the Cerrado has encountered various problems, for instance, the slow growth and the lack of knowledge about the cultivation practices. In order to better use the available water resources and to produce quality seedlings, this study aimed to evaluate different substrates and water levels on the emergence and initial growth of Alibertia sessilis Schum. seedlings. The effects of the following substrates were evaluated: dystroferric Red Latosol (Oxisol), Oxisol +sand (1:1 v/v), Oxisol + sand + semi-decomposed poultry litter (1:1:0.5 v/v), Oxisol + sand 2 + semi-decomposed poultry litter (1:2:0.5 v/v) and Oxisol + commercial-substrate-CS (1:1 v/v) associated with the levels of irrigation of 25, 50, 75 and 100% of the water holding capacity in the substrate (WHC). The best results for emergence percentage, initial growth and quality of seedlings were observed in the substrates Oxisol + sand 2 + poultry litter (1:2:0,5) at 100% of WHC. There was no emergence at 25% of WHC. Keywords: Rubiaceae, marmelinho, fruit of the Cerrado. ResumoSubstratos e disponibilidade hídrica na emergência e crescimento inicial de mudas de Alibertia sessilis Schum. O cultivo de espécies nativas no Cerrado tem esbarrado em vários problemas, entre eles, o crescimento lento e a carência de conhecimentos sobre as práticas culturais. A fim de melhor utilizar os recursos hídricos disponíveis e produzir mudas de qualidade, objetivou-se no presente trabalho avaliar diferentes substratos e níveis de água na emergência e no crescimento inicial das mudas Alibertia sessilis Schum. Foram avaliados os efeitos dos substratos Latossolo Vermelho distroférrico (LVd), LVd +areia (1:1 v/v), LVd + areia + cama de frango semidecomposta (1:1:0,5 v/v), LVd + areia 2 + cama de frango semidecomposta (1:2:0,5 v/v) e LVd + substrato comercial -SC (1:1 v/v) associados aos níveis de irrigação de 25, 50, 75 e 100% da capacidade de retenção de água no substrato (CRA). Os melhores resultados para porcentagem de emergência, crescimento inicial e qualidade das mudas foram observados nos substratos LVd + areia 2 + cama de frango (1:2:0,5) a 100% da CRA. Não houve emergência a 25% da CRA. Palavras-chave: Rubiaceae, marmelinho, frutífera do Cerrado.

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How the fluctuations of water levels affect populations of invasive bivalve Corbicula fluminea (Müller, 1774) in a Neotropical reservoir?

Brazilian Journal of Biology ◽

10.1590/1519-6984.09113 ◽

2015 ◽

Vol 75 (1) ◽

pp. 135-143 ◽

Cited By ~ 8

Author(s):

LRP. Paschoal ◽

DP. Andrade ◽

G. Darrigran

Keyword(s):

Population Structure ◽

Spatial Distribution ◽

Water Column ◽

Shell Length ◽

Native Species ◽

Corbicula Fluminea ◽

Water Levels ◽

Hydroelectric Power Station ◽

Hydroelectric Power ◽

Significant Difference

Corbicula fluminea is an invasive bivalve responsible for several environmental and financial problems around the globe. Despite the invasive potential of this species, it suffers certain restrictions in lentic environments due to natural phenomena that significantly affect its population structure (e.g. water column fluctuation and sunlight exposure). The present study addresses how temporal decline of the water level in a Neotropical reservoir and exposure to sunlight affect the population structure of C. fluminea. Samplings were carried out twice in the reservoir of Furnas Hydroelectric Power Station (HPS) (Minas Gerais, Brazil), in 2011 and 2012. Population density, spatial distribution and mean shell length of C. fluminea were estimated for each year after sampling in 51 quadrats (0.0625m2) placed on three transects at different distances along the reservoir margins (0, 10 and 20 m from a fixed-point). We observed a predominance of C. fluminea in both years, with a simultaneous gradual decrease in density and richness of native species in the sampling area. Significant differences in density of C. fluminea were registered at different distances from the margin, and are related to the temporal variability of physical conditions of the sediment and water in these environments. We also registered a trend toward an increase in the density and aggregation of C. fluminea as we moved away from the margin, due to the greater stability of these areas (>10 m). The mean shell length of C. fluminea showed significant difference between the distinct distances from the margin and during the years, as well as the interaction of these factors (Distances vs.Years). These results were associated with the reproductive and invasive capacity of this species. This study reveals that these temporal events (especially water column fluctuation) may cause alterations in density, spatial distribution and mean shell length of C. fluminea and the composition of the native malacofauna in Neotropical lentic environments.

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EFFECTS OF SUBSTRATE AND WATER AVAILABILITY ON THE INITIAL GROWTH OF Alibertia edulis RICH.

FLORESTA ◽

10.5380/rf.v49i1.57122 ◽

2018 ◽

Vol 49 (1) ◽

pp. 089 ◽

Cited By ~ 2

Author(s):

Tatiane Sanches Jeromini ◽

Leandro Henrique de Sousa Mota ◽

Silvana De Paula Quintão Scalon ◽

Daiane Mugnol Dresch ◽

Lourenço Quintão Scalon

Keyword(s):

Water Availability ◽

Native Species ◽

Water Retention ◽

Water Levels ◽

Chicken Manure ◽

Initial Growth ◽

Randomized Design ◽

Completely Randomized Design ◽

Red Latosol

Alibertia edulis Rich. is a native species of the Brazilian Cerrado and can be used for reforestation of degraded areas. In addition, it produces edible fruits. The objective of this study was to evaluate the effect of substrates and water levels on the emergence, initial growth, and quality of seedling of A. edulis. The substrates tested were: latosol (L), latosol + sand (L + S = 1:1), latosol + sand + chicken manure (L + S1 + CM = 1:1:0,5), latosol + sand + chicken manure (L + S2 + CM = 1:2:0,5), and latosol + commercial substrate (L + C = 1:1); and the water retention capacities (WRC) tested were: 25, 50, 75, and 100%. The experiment was carried through in a completely randomized design and subdivided into a plot scheme, in which the plots represented water availability and the subplots represented the substrates. Latosol + commercial substrate at 100% of WRC provided the best conditions for emergence, initial growth and formation of seedlings of A. edulis. Sowing in the substrate Dystroferric Red Latosol isolated at 25% of WRC should not be used for the formation of seedlings of this species.

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