Wetland Edge Research Articles

Do River Otters Conform to Habitat Suitability Assessments?

AbstractRiver otters (Lontra canadensis) were reintroduced from 1994–1996 into parts of Illinois where the species was extirpated due to over harvest and habitat loss. At the time of reintroduction, managing for the persistence of the population through habitat was very important and research was conducted to determine which watersheds had quality habitat and which needed increased management and protection. In a study conducted in the mid‐1990s, biologists used pattern recognition (PATREC) modeling to identify high and low quality habitat for river otters at the subunit level (i.e., divided watershed), based on specific habitat attributes including wooded area, sinuosity, and wetland edge. We compared the habitat quality ratings of subunits with river otter use at 112 bridge sites from 2012–2014 to determine if river otters have distributed themselves according to previously determined habitat quality. We found that the PATREC model was a poor predictor of river otter use when sites were located close to the otter reintroduction points. The PATREC model was most likely a poor predictor of river otter use due to an over‐emphasis on the importance of woody vegetation to habitat suitability for river otter in the model. We recommend that future work on the assessment of habitat suitability for river otter use, and accuracy of this assessment, be conducted at a local spatial scale and over a shorter temporal scale. We also recommend that watershed policies and habitat assessments consider changes to land‐cover and follow an adaptive management approach to assess habitat suitability for reintroduced species.

Conditions of contaminant distribution in the wetland water of Western Siberia (the Russian Federation)

The models of pollutants’ distribution in the wetland waters of Western Siberia (Tomsk Oblast, Russia) have been considered. The models’ application allows describing the observed changes in the chemical composition of active layer of wetland waters with satisfactory accuracy. With these models, the most significant impact of sewage discharge on the local wetland water composition is observed in wetland edge area of up to 150–300 m in width. Even in this area it is possible to minimize the impact of sewage discharge on the wetlands provided the concentration in sewage water is 1.14-1.3 time more than the background concentration.

Factors driving structure of natural and anthropogenic forest edges from temperate to boreal ecosystems

AbstractQuestionsWhat factors control broad‐scale variation in edge length and three‐dimensional boundary structure for a large region extending across two biomes? What is the difference in structure between natural and anthropogenic edges?LocationTemperate and boreal forests across all of Sweden, spanning latitudes 55–69° N.MethodsWe sampled more than 2000 forest edges using line intersect sampling in a monitoring programme (National Inventory of Landscapes in Sweden). We compared edge length, ecosystem attributes (width of adjacent ecosystem, canopy cover, canopy height, patch contrast in canopy height, forest type) and boundary attributes (profile, abruptness, shape) of natural edges (lakeshore, wetland) with anthropogenic edges (clear‐cut, agricultural, linear disturbance) in five regions.ResultsAnthropogenic edges were nearly twice as abundant as natural edges. Length of anthropogenic edges was largest in southern regions, while the abundance of natural edges increased towards the north. Edge types displayed unique spectrums of boundary structures, but abrupt edges dominated, constituting 72% of edge length. Anthropogenic edges were more abrupt than natural edges; wetland edges had the most gradual and sinuous boundaries. Canopy cover, canopy height, patch contrast and forest type depended on region, whereas overall boundary abruptness and shape showed no regional pattern. Patch contrast was related to temperature sum (degree days ≥ 5 °C), suggesting that regional variability can be predicted from climate‐controlled forest productivity. Boundary abruptness was coupled with the underlying environmental gradient, land use and forest type, with higher variability in deciduous than in conifer forest.ConclusionsEdge origin, land use, climate and tree species are main drivers of broad‐scale variability in forest edge structure. Our findings have important implications for developing ecological theory that can explain and predict how different factors affect forest edge structure, and help to understand how land use and climate change affect biodiversity at forest edges.

Do geographically isolated wetlands influence landscape functions?

Geographically isolated wetlands (GIWs), those surrounded by uplands, exchange materials, energy, and organisms with other elements in hydrological and habitat networks, contributing to landscape functions, such as flow generation, nutrient and sediment retention, and biodiversity support. GIWs constitute most of the wetlands in many North American landscapes, provide a disproportionately large fraction of wetland edges where many functions are enhanced, and form complexes with other water bodies to create spatial and temporal heterogeneity in the timing, flow paths, and magnitude of network connectivity. These attributes signal a critical role for GIWs in sustaining a portfolio of landscape functions, but legal protections remain weak despite preferential loss from many landscapes. GIWs lack persistent surface water connections, but this condition does not imply the absence of hydrological, biogeochemical, and biological exchanges with nearby and downstream waters. Although hydrological and biogeochemical connectivity is often episodic or slow (e.g., via groundwater), hydrologic continuity and limited evaporative solute enrichment suggest both flow generation and solute and sediment retention. Similarly, whereas biological connectivity usually requires overland dispersal, numerous organisms, including many rare or threatened species, use both GIWs and downstream waters at different times or life stages, suggesting that GIWs are critical elements of landscape habitat mosaics. Indeed, weaker hydrologic connectivity with downstream waters and constrained biological connectivity with other landscape elements are precisely what enhances some GIW functions and enables others. Based on analysis of wetland geography and synthesis of wetland functions, we argue that sustaining landscape functions requires conserving the entire continuum of wetland connectivity, including GIWs.

Towards multi-level biomonitoring of nematodes to assess risk of nitrogen and phosphorus pollution in Jinchuan Wetland of Northeast China

Cultivation for agricultural production often poses threats to nearby wetlands ecosystems in fertile landscapes. In this study, nematode ecological indexes were assessed through the main soil properties of the wetlands, farmlands, and edges of wetlands and farmlands in Jinchuan Wetland by the random sampling. Behavior and reproduction in Caenorhabditis elegans (C. elegans) exposed to the sampled waters were also examined. Stress proteins Hsp70 and Hsp90 were measured both in the living field samples of C. elegans and the lab-tested C. elegans. Our results suggested that disturbance to wetland ecosystems by nitrogen and phosphorus reduced nematode richness and proportions of bacterivore nematodes. Bacterivore nematode diversity and plant-parasitic ecological index were proven to be sensitive indicators of the ecological health of wetlands. Nematode Hsp70 were useful biosensors to monitor and assess the levels of nitrogen and phosphorus pollutions in wetlands. Furthermore, multi-level soil faunal assessments by canonical correspondence analysis showed that Jinchuan Wetland is threatened with non-point source pollution from nearby farmlands.

Responses of SOM decomposition to changing temperature in Zoige alpine wetland, China

Alpine wetlands are considered to be very sensitive to future climate warming. Understanding changes in decomposition rates (Rs) of soil organic matter (SOM) and temperature sensitivity (Q 10) in alpine wetlands, under the scenarios of a warming climate and decreasing soil moisture, is important for predicting their carbon (C) budget. Here, we established three sampling transects from wetland edge to meadow in the Zoige alpine wetlands in China, which represented the gradients of decreasing soil moisture. We conducted an incubation experiment (5–25 °C) to explore changes in Q 10 with the degradation process from alpine wetland to alpine meadow. The results showed that temperature significantly influenced Rs in all locations. Rs first increased from site I to site IV and then decreased from site IV to site V. However, Q 10 and activation energy (E a ) showed no apparent trends with soil coming from sites along a moisture gradient. Overall, the Q 10 values in the wetland (sites 1.50) were significantly lower than that of the meadow (1.83); similar trends were observed for E a . In addition, E a exhibited a negative logarithmic relationship with C quality indices in all locations, which suggested that the C quality-temperature hypothesis is applicable to both alpine wetlands and meadows. These findings provide a theoretical foundation for predicting the potential influences of warming climate on soil C turnover and storage in alpine wetlands.

New mapping techniques to estimate the preferential loss of small wetlands on prairie landscapes

AbstractReliable estimates of wetland loss require improved wetland inventories and effective monitoring programmes. The Prairie Pothole Region of North America is experiencing rapid urban, agricultural and economic development, which places wetlands at risk, especially small geographically isolated wetlands. This loss is concomitant with a loss of ecosystem services. To improve upon current wetland inventories, a method for mapping wetlands using an automated object‐based approach was developed for a regional watershed in Alberta. The method improves upon existing wetland mapping methods by effectively mapping small wetlands and better capturing the convolution of wetland edges. This approach uses digital terrain objects derived from light detection and ranging data, from which 130 157 wetlands were identified. Wetland loss estimates (% number and % area) were obtained by applying a wetland area versus frequency power‐law function to the wetland inventory. We estimated a 16.2% historic loss of wetland number and a 2.6% loss of wetland area, with the size of these lost wetlands <0.04 ha. The improved techniques for mapping wetland loss and estimating wetland loss provide a more accurate representation of the magnitude of wetland loss in the Prairie Pothole Region. Copyright © 2015 John Wiley & Sons, Ltd.

The influence of differing protected area status and environmental factors on the macroinvertebrate fauna of temperate austral wetlands

One means of conserving wetlands is to designate the area around them as ‘protected’. Although many different types of protected areas exist, ranging from international (Ramsar-listed) to local importance, there is little information on how the type of protection influences biodiversity conservation. Studies of the effectiveness of protected area systems are a priority, if we are to understand their importance and design systems effectively. Many Tasmanian wetlands are regarded as having high to very high conservation values with more than 60% located within protected areas. This study tested macroinvertebrate richness and assemblage responses to a range of environmental attributes and differing types of protected area status at 66 protected Tasmanian (Australian) wetlands. Two hundred and eighteen taxa were identified with an average of 33 species (or morphospecies) and 18 families recorded per wetland. The wetland assemblages were idiosyncratic, four families contributed 21% of the total recorded and only two families contributed greater than 10%. Wetlands were not significantly nested on the basis of the composition of their macroinvertebrate assemblages. No single environmental attribute had a strong relationship with macroinvertebrate richness or assemblage composition and neither species richness nor assemblage composition varied significantly between different types of protected areas. Although the majority of protected area types were designed to support terrestrial conservation objectives rather than wetland values, our results suggest that the latter were also afforded protection. The state of the proximal zone (the terrestrial zone within 50m of the wetland edge) and the type of aquatic habitat present (macrophyte or sediment-dominated substrates) were the most important determinants of macroinvertebrate richness and assemblage composition across all types of protected wetlands. These results suggest that for temperate austral wetlands located within protected areas, the macroinvertebrate fauna will be best conserved by minimal disturbance of proximal lands.

Spatial distribution of resting stages of crustaceans and other aquatic invertebrates in playa wetlands

Crustaceans in temporary wetlands have resting stages that allow them to persist in the soil during dry phases. We examined the spatial distribution of viable resting stages of invertebrates in the soil of playa wetlands. We took soil cores near the center and near the edge of the playas and in the surrounding upland of the dry playas. We then rehydrated the soil cores for two weeks. We found higher abundance and taxa richness, and a different taxonomic composition in the playa center than in the upland. Invertebrate abundance and taxa richness were intermediate at the wetland edge and taxonomic composition overlapped with that from the center and edge. Crustaceans (tadpole shrimps and calanoid copepods) were more abundant in the wetland center than from the edge or upland. Environmental factors and invertebrate behavior may play a role in organizing the spatial distribution of aestivating stages of aquatic invertebrates.

Geographic variation in mangrove flooding and accessibility for fishes and nektonic crustaceans

Intertidal habitats are only available to most nekton when inundated by tides. We assessed the variability of access to mangrove habitats for aquatic organisms over 3500 km of Australia’s east coast. After determining the elevation of the lower mangrove edge across 19 locations, we used 6 years of historic hourly tide gauge readings to estimate wetland edge flooding frequency, duration, and depth at each location. Although mangrove edges broadly tracked mean sea level along the east coast, deviations in edge elevation corresponded to substantial geographic variation in flooding dynamics. Mangrove edges were flooded from as little as 20% of the time in central Queensland sites, to as much as 90% of the time during some seasons in northern New South Wales. Flooding frequency and depth were also highly variable, with some mangrove edges flooding and draining almost twice as frequently as others. Flooding depth profiles revealed dynamic patterns of flooding of mangrove habitat. The variability in flooding dynamics demonstrates that the availability of mangrove habitat to aquatic organisms varies significantly among locations. This variability in flooding patterns suggests the nature of mangrove use and the functional value of these habitats for fishes and nektonic crustaceans may differ substantially among regions.

Predicting bobcat abundance at a landscape scale and evaluating occupancy as a density index in central Wisconsin

The abundance of low-density species like carnivores is logistically difficult to directly estimate at a meaningful scale. Predictive distribution models are often used as a surrogate for density estimation. But because density can continue to increase as occupancy asymptotes at 1, occupancy may have little value as an index, and home range expansion in marginal habitat may further confound the association. We sought to estimate bobcat population size at a landscape scale (14,286 km2) in central Wisconsin, which provided an opportunity to relate predicted occurrence to individual space use and population density. We sampled bobcats using motion-sensitive trail cameras at 9 arrays across central Wisconsin. We estimated bobcat site-specific occupancy, and regressed these estimates as linear or asymptotic functions of site-specific density to determine the strength and shape of their association. We subsequently modeled both parameters relative to habitat covariates and repeated the regression process. A linear functional relationship between density and occupancy was most supported when detection parameters were held constant (wi= 0.97, R2 = 0.72) and when detection, occurrence, and density were modeled as a function of habitat covariates (wi= 0.99, R2 = 0.95). This suggests that repeated presence-absence data alone may be an efficient and reliable method for inferring spatial patterns in bobcat density or identifying habitat types with greater density potential in the northern parts of its range. Bobcat occupancy and density were both positively associated with surrounding woody cover and wetland edge density. Our most supported spatially explicit capture-recapture model estimated bobcat abundance as 362 adult individuals (95% CI 272–490) across the study area. © 2015 The Wildlife Society.

Detecting the effects of water regime on wetland plant communities: Which plant indicator groups perform best?

Water regime is a primary driver of patterns in wetland vegetation composition. Differences in composition can be used as indicators of differences in water regime. We used vegetation point intercept data collected from 51 wetland monitoring plots in the Blue Mountains, south-eastern Australia, to determine which of three indicator group classifications, growth forms, water plant functional groups (WPFGs) or wetland indicator categories (WICs), demonstrated the most consistent differences between vegetation communities from plot sample groups differing in location (wetland edge or core) and surface water availability (typically inundated or damp). PERMANOVA tests showed significant differences between core and edge plot communities analysed by growth form or WIC relative frequencies, but only when tree canopy data (higher in edge plots, which were abutting woodland) was included. Significant differences in communities (PERMANOVA, p≤0.02) were detected between inundation categories for all classification methods when tree data were included, but not for WIC data when tree data were excluded. Overall, ordination plots and ANOSIM R values showed the most consistent community-level differences (least overlap in sample groups) between inundation categories when data were classified by WPFGs, followed by growth forms. ANOVA tests on individual indicator group relative frequencies showed that WPFG classification provided the most indicator groups differing significantly in relative frequency between inundation categories, with these groups also collectively comprising a much higher proportion of the total vegetation recorded per plot than the growth forms or WICs that differed between categories.

Postbreeding Habitat Use of the Rare, Pure-Diploid Blue-spotted Salamander (Ambystoma laterale)

Abstract The pure-diploid Blue-spotted Salamander (Ambystoma laterale) is among the rarest amphibians in northeastern North America, and data on its ecology are sparse. We assessed the movement ecology and terrestrial habitat use of A. laterale using radio- and passive integrated transponder (PIT) tag- telemetry. We radio-tracked 22 A. laterale for a median of 54 days (range 6–126 days) in the spring and summer of 2009 and 2010. Using a modified PIT tag reader, we conducted 34 in situ surveys during the spring and summer of 2009 through 2011, resulting in 42 relocations. We detected salamanders at a median straight-line distance of 67 m (range 7–281 m) from their breeding wetland. The life zone (i.e., critical terrestrial habitat), encompassing 95% of observed salamander movements, extended 152 m from the edge of the breeding wetland. Eighteen radio-tracked salamanders migrated to upland forest, three to a wet meadow, and one to a red maple (Acer rubrum) swamp. Salamanders used upland forest and wet meado...

A colourful youth: ontogenetic colour change is habitat specific in the invasive Nile perch

External body colour is an important trait contributing to phenotypic diversity and individual fitness in fish species. In this study, we use a combination of experimental techniques and field observations to examine patterns of colour divergence in the introduced Nile perch population of Lake Nabugabo, Uganda. We aim to determine whether the proportion of black–brown body colouration of Nile perch differs over a number of size classes, across ecologically distinct wetland edge and forest edge habitats, and whether these differences are the result of rapid (physiological) or ontogenetic (morphological) colour change. We found substantial colour differences in Nile perch between habitats, but trends were not consistent across size classes. Small Nile perch ( 40 cm SL) Nile perch. Inter-habitat differences in colour in the small size class, and shifts in colour from juvenile to adult appear to be the result of morphological colour change associated with distinct ontogenetic shifts in resource use.

Habitat edges affect patterns of artificial nest predation along a wetland-meadow boundary

Wetland habitats are among the most endangered ecosystems in the world. However, little is known about factors affecting the nesting success of birds in pristine grass-dominated wetlands. During three breeding periods we conducted an experiment with artificial ground nests to test two basic mechanisms (the matrix and ecotonal effects) that may result in edge effects on nest predation in grass-dominated wetland habitats. Whereas the matrix effect model supposes that predator penetrate from habitat of higher predator density to habitat of lower predator density, thus causing an edge effect in the latter, according to the ecotonal effect model predators preferentially use edge habitats over habitat interiors. In addition, we tested the edge effect in a wetland habitat using artificial shrub nests that simulated the real nests of small open-cup nesting passerines. In our study area, the lowest predation rates on ground nests were found in wetland interiors and were substantially higher along the edges of both wetland and meadow habitat. However, predation was not significantly different between meadow and wetland interiors, indicating that both mechanisms can be responsible for the edge effect in wetland edges. An increased predation rate along wetland edges was also observed for shrub nests, and resembled the predation pattern of real shrub nests in the same study area. Though we are not able to distinguish between the two mechanisms of the edge effect found, our results demonstrate that species nesting in wetland edges bordering arable land may be exposed to higher predation. Therefore, an increase in the size of wetland patches that would lead to a reduced proportion of edge areas might be a suitable management practice to protect wetland bird species in cultural European landscapes.

Diversidad de anuros en humedales del Centro de Investigación Amazónica Macagual, Florencia, Caquetá, Colombia

Objective: Richness, abundance was determined and a comparison of anurans was conducted in two Macagual Wetlands Research Center (Caqueta, Colombia). Methodology: the capture technique that consisted thorough intensive search both auditory and visual, for the year 2012, from March to November. Results: registering a total of 144 individuals, divided into six species, four genera and two families (Hylidae and Leptodactylidae). The greater dominance as the Simpson index (D), obtained Wetland Potrero. Most Evenness (1-D) was found in the Wetland Edge Forest and by Margalef index which shows wealth, obtained Wetland Forest, due to plant heterogeneity, creating optimal climatic conditions for anurans, determining narrower niches and more species per unit area. These conditions favor the diversity and abundance of frogs and various sites that give them shelter, food and oviposition. Conclusion: The present Potrero wetland greater abundance, with 75 individuals and greater dominance, in terms of Wetland Forest Edge, 69 individuals were captured and greater diversity was obtained due to a better distribution or homogeneity of space.

Variability in the distribution and dissipation of the herbicide thifensulfuron-methyl in a prairie wetland

Surface runoff, atmospheric transport, spray drift, and other transport processes result in frequent herbicide detections in prairie dugouts and wetlands. Thifensulfuron-methyl is a commonly used sulfonylurea herbicide with high phytotoxicity that could pose a potential threat to wetland ecosystems. The dissipation of thifensulfuron-methyl in a prairie wetland was monitored in the water column and wetland sediments during four months following herbicide addition. Variability in herbicide concentrations relative to physico-chemical characteristics of the wetland was evaluated by collecting water samples for herbicide analysis from two locations near the middle of the wetland and at two depths (0.5 m [1.6 ft] below the surface and 0.1 m [0.3 ft] above the wetland floor) at each location. Sediment samples were collected beneath the water sampling locations and at two sites near the wetland margin. Water temperature was constantly monitored throughout the study period, and a range of wetland properties was measured at each sampling. Higher temperatures and greater diurnal fluctuations were measured at 0.5 m depth than at 0.1 m from the bottom. Conversely, electrical conductivity of the wetland water was consistently greater at depth than near the surface of the wetland. Concentrations of thifensulfuron-methyl were consistently higher at 0.5 m depth than at 0.1 m from the bottom. Dissipation of thifensulfuron-methyl was biphasic at both depths, dissipating more rapidly initially (most of the herbicide was lost from the water column after 7 days) such that initial time for 50% dissipation values were around 2 days. Dissipation in the second phase proceeded at a much slower rate, taking three to five weeks for 50% of the residual herbicide to dissipate (quantifiable concentrations were still measured after 128 days). Thifensulfuron-methyl was detected in sediments collected near the wetland edge but not in samples taken from the deeper parts of the wetland. The physico-chemical environment of the wetland (temperature, pH, and dissolved oxygen [DO]) affected the distribution of thifensulfuron-methyl and should be considered in the development of sampling regimes and pesticide fate models.

Wetlands in Changed Landscapes: The Influence of Habitat Transformation on the Physico-Chemistry of Temporary Depression Wetlands

Temporary wetlands dominate the wet season landscape of temperate, semi-arid and arid regions, yet, other than their direct loss to development and agriculture, little information exists on how remaining wetlands have been altered by anthropogenic conversion of surrounding landscapes. This study investigates relationships between the extent and type of habitat transformation around temporary wetlands and their water column physico-chemical characteristics. A set of 90 isolated depression wetlands (seasonally inundated) occurring on coastal plains of the south-western Cape mediterranean-climate region of South Africa was sampled during the winter/spring wet season of 2007. Wetlands were sampled across habitat transformation gradients according to the areal cover of agriculture, urban development and alien invasive vegetation within 100 and 500 m radii of each wetland edge. We hypothesized that the principal drivers of physico-chemical conditions in these wetlands (e.g. soil properties, basin morphology) are altered by habitat transformation. Multivariate multiple regression analyses (distance-based Redundancy Analysis) indicated significant associations between wetland physico-chemistry and habitat transformation (overall transformation within 100 and 500 m, alien vegetation cover within 100 and 500 m, urban cover within 100 m); although for significant regressions the amount of variation explained was very low (range: ∼2 to ∼5.5%), relative to that explained by purely spatio-temporal factors (range: ∼35.5 to ∼43%). The nature of the relationships between each type of transformation in the landscape and individual physico-chemical variables in wetlands were further explored with univariate multiple regressions. Results suggest that conservation of relatively narrow (∼100 m) buffer strips around temporary wetlands is likely to be effective in the maintenance of natural conditions in terms of physico-chemical water quality.

Long-term denitrification rates in created riverine wetlands and their relationship with environmental factors

Created wetlands that mimic structure and functions of natural wetlands have been widely applied mainly as a means for water quality improvement. Denitrification is a process that is considered to be important, especially in wetlands with their anaerobic soils, for the removal of nitrogen. In this study, we assessed the temporal and spatial patterns of denitrification from created wetlands over a relatively long time scale of 6 years. We found that denitrification rates were highly variable, ranging from 2.1 to 5288μgm−2h−1 over that 6-year study period. Overall denitrification followed expected seasonal patterns, depending on temperature and nitrate concentrations in the surface water. We also found higher denitrification in open water and deep marsh areas than in shallow and wetland edge areas, likely the result of oxygen depletion in deeper water areas. Denitrification was also regulated by hydrologic regime. The highest mean denitrification rate (506μgm−2h−1) was observed in 2004 when the wetlands received artificial hydrologic pulses and the lowest rates (217μgm−2h−1) were observed in 2008, when wetlands were drier than in other years. The presence/absence of vegetation had little influence of spatial and seasonal variations of denitrification. However, annual variations of denitrification tended to be related to vegetation productivity as indicated by aboveground net primary productivity. This result suggests that denitrification rates may have been suppressed by plants creating aerobic condition in their rhizospheres. The high spatio-temporal patterns of denitrification seen in these created wetlands were caused mainly by a complex interaction of hydrology, nitrate-nitrogen concentrations and temperature.

Spatiotemporal variation in the microclimatic edge effect between wetland and farmland

The creation of wetland edges associated with anthropogenic fragmentation is common in wetland landscapes and brings about a unique microclimatic change that affects adjacent farmland. However, microclimatic edge effects within this kind of landscape are not well quantified. Thus, using a study site located in the northeastern Sanjiang National Nature Reserve, China, we investigated the spatiotemporal variations in the microclimatic variables of the surface layer across the wetland‐farmland edge. Air temperature and relative humidity data were collected continuously along a horizontal transect at four different heights over different periods, and the relative humidity was converted to specific humidity. Sigmoid models were used to fit the horizontal gradients of microclimatic edge effects. Then, based on the parameters in the fitted models, the characteristics of the edge effects were quantified with two indices, the magnitude of edge effect (MEE) and the spatial range of edge effect (REE). Under a light wind condition, the microclimatic features across the edge generally presented sigmoid ecological gradients in the horizontal direction, with unique spatial and temporal patterns: (1) In a normal year, wetland patches cooled and moistened the adjacent farmlands during the daytime and had a warming‐moistening effect during the nighttime. (2) Vertically, the absolute MEE value of the microclimatic variables decreased, but the REE increased with increasing height. (3) The MEE and REE for air temperature and specific humidity varied with the time of day, both shifting at dawn and dusk when the gradients were absent. (4) At the interannual scale, when compared to the farmland, the wetland was cooler at night in a dry year but warmer in a normal year. The detection of spatiotemporal microclimatic patterns in the wetland‐farmland edge zone may enable further understanding of how wetland degradation affects adjacent farmland ecology under human disturbance and promote better management and restoration of fragmented wetlands.