Integrity Of Wetlands Research Articles

Integrating Wetlands as Nature-Based Solutions for Sustainable Built Environments

Wetlands are ecosystems that can provide numerous services critical for sustainable development, especially in urban areas, by ensuring environmental stability. The wetlands receive increasing recognition as Nature-Based Solutions (NBSs) to environmental challenges. This review synthesizes the numerous roles of wetlands as NBSs for promoting sustainability in both rural and urban environments and highlights the potential contributions of multiple wetland services and benefits towards sustainable built environments. The review methodology involved an article search from various databases with the utilization of specific keywords in an organized framework to understand the contribution of wetlands as NBSs. The articles were reviewed to provide a comprehensive analysis of the existing research on the associated topics, focusing on specific sub titles and pre-selected themes. The findings of this review identify various parameters through which wetlands contribute to sustainable built environments, including ecological resilience, storm water management, climate adaptation, biodiversity enhancement, recreational opportunities, pollution control, and cultural values. The review also encompasses case studies of different types of wetland features such as riparian buffer zones, retention ponds, reed beds, bio swales, rain gardens, constructed wetlands, etc. in the urban environment and their contribution as NBSs. These contributions are discussed in terms of integration in urban development planning in different segments. Future work recommendations consist of a holistic integration of wetlands into urban planning and design considerations to promote more resilient, healthy, and sustainable built environments for present and future generations.

Evaluating the Effect of Common Carp Control on Restoration of a Coastal Wetland in the Laurentian Great Lakes

Great Lakes coastal wetlands are under considerable stress from numerous anthropogenic threats, including the introduction of invasive species. Common Carp, an invasive species in North America, has been well documented as an influential wetland stressor. This study documents the impact of Common Carp reintroduction on a restored wetland fish community and abiotic and vegetation variables. Oshawa Second Marsh was restored using an exclusion berm with a fish grate and manual water-level drawdown to re-establish vegetation. Five years into restoration monitoring, Common Carp regained access to the wetland after the fish grate was vandalized. Fish community health was monitored over time using multimetric and multivariate approaches based on abiotic and vegetation variables. Improvements in fish community health were observed during restoration monitoring, but after Common Carp reintroduction, fish community health decreased and the community homogenized. Seven of the ten abiotic and vegetation variables monitored changed significantly after Common Carp reintroduction. This study highlights the impact that Common Carp has on the functional integrity of coastal wetlands and the significance of its management for restoration.

Ecological values of Ourkiss wetland (Oum El Bouaghi province - Algeria), an overview of waterbirds diversity and richness

The monitoring of waterbirds’ abundance and richness serves as the primary method for scientists to characterize the ecological values and diversity profile of wetlands. This survey was specifically conducted in Ourkiss wetland, situated in the Oum El Bouaghi province of East Algeria, spanning from January to May 2013. The study aimed to elucidate the ecological significance of Ourkiss wetland by analyzing various parameters, including the abundance, richness, diversity profile, and conservation status of its waterbird population. A total of 23 species, representing 11 families, were documented during the survey period, with Anatidae and Rallidae emerging as the most prevalent taxa. Notably, Ourkiss wetland exhibited two distinct populations: the “wintering population” and the “breeding population,” with significant waterbird activity observed during migration between the northern and southern regions. The presence of the endangered species Oxyura leucocephala further underscores the ecological importance of this wetland. Noteworthy peaks in waterbird diversity were particularly observed in April, as indicated by richness and Shannon indices. To safeguard the ecological integrity of Ourkiss wetland, it is strongly recommended to intensify conservation efforts and implement effective management plans.

Tourism on the roof of the world: Socio-ecological impacts of tourism on the Indian Trans-Himalaya

Tourism is a rapidly developing industry in ecologically sensitive remote areas, especially in developing countries. Although a lucrative livelihood alternative, it is often responsible for degrading the environment and stratifying the socio-economic setup, if not managed prudently. We assessed the impact of tourism on ecological integrity and local livelihood in wetlands of Changthang Wildlife Sanctuary (CWLS), Indian Trans-Himalaya. Change in behaviour of wetland birds was studied using flight initiation distance (FID) approach to understand the ecological sensitivity of CWLS. We evaluated livelihood contribution of tourism and attitude of local people towards tourism as a futuristic livelihood opportunity using questionnaire-based interviews and focus group discussions. Although traditional communities of CWLS see tourism as a livelihood opportunity; they are still sceptical about its effectiveness and indicated leakage of tourism benefits. People were also dubious about its impact on their socio-cultural and environmental structure. FID estimates have shown level of sensitivity among wetland birds towards presence of tourists. We recommend, site-specific FID based ‘minimum approach distances’ of most sensitive species for delineating buffers around wetlands to ensure no disturbance to waterbirds. Community managed nature-based tourism is suggested to maximise the tourism benefits to local people. Prototypical sustainable tourism activities should be endorsed in the region that can elicit advancement of local economy and efficacy of conservation efforts.

Sitatunga (Tragelaphus spekii) food sources and habitat use in Marsh–Savannah‐cultivation mosaics

AbstractWetland conversion threatens wetland specialists by reducing their core habitat. The sitatunga is a wetland specialist with declining populations. However, knowledge of sitatunga ecology and threats is limited, particularly outside protected areas. We examined sitatunga food sources, and habitat use in undisturbed Marshes and Marsh–Savannah transition blocks, and a Cultivated (disturbed) block in River Mayanja wetland, central Uganda. We recorded indirect indices and sightings of sitatunga along a 10 km transect in each block, and surveyed food sources in 34 plots along the transects. Our results indicate that the indices and sightings of Sitatunga had lower relative frequency in the Cultivated than in the Marshes and Marsh–Savannah transition blocks. Sitatunga feed on 39 plant species in 13 families and six growth forms; grasses, herbs, sedges, climbers, shrubs and water weeds. Cyperus papyrus, Echinochloa pyramidalis, Leersia hexandra accounted for 58% of sitatunga food sources. There were more individuals and species with Sitatunga feeding activity in the Marshes and Marsh–Savannah transition blocks than in the Cultivated block. Our results show that sitatunga habitat use and food sources are constrained in disturbed habitats while threats are intensified. To maintain wetland integrity and stability of sitatunga populations, stakeholders need to address wetland encroachment.

Effectiveness of rapid sampling assessments for wetland-breeding amphibians

A primary response to the Clean Water Act has been the development of numerous indices of biotic integrity (IBI) using various taxonomic groups to assess the condition of water bodies in the United States. The IBI is a frequently used approach for assessing the ecological integrity of streams; however, it is less commonly applied to wetland systems, despite the scientific and policy needs to assess wetland condition and develop ecological performance goals for wetland monitoring, creation, and restoration. Although a great deal of attention has been given to wetland acreage due to the “no net loss” policy over the past two decades, much less attention has been given to the ecological integrity of these same wetlands. To assess wetland health and function, regulatory agencies and land managers need clear performance standards that are based on the ecology of wetland organisms. To address this need, we sampled 242 wetlands distributed across 45 managed properties in Illinois, U.S.A. over three years (2012–2014) for adult and larval amphibians (12 samples per wetland). Amphibian assemblages make up critical ecological components of many wetland ecosystems and are considered useful bioindicators of environmental change because they are sensitive to various forms of environmental and habitat alteration. We developed an amphibian-based IBI (hereafter aIBI) for the assessment of seasonal wetlands and optimal sampling strategies to best quantify these wetlands (i.e., assessment of time and effort). The aIBI applied a conservation coefficient to all species captured; conservation coefficients were developed through a survey of amphibian experts (n = 16). We captured 25 amphibian species with an average of 7.11 amphibian species (range 1–13) per site. Using the species occurrence data collected from both dipnet and minnow trap surveys over 12 survey periods, we assessed the average percent error in the estimation of aIBIs and species richness. Our results show that a wetland can be accurately evaluated with amphibians in one field season, but that multiple samples during that field season will be necessary. We show that 4–5 surveys using multiple methods distributed throughout the spring and summer are required. This level of effort may be incongruent with existing definitions of ‘rapid assessment’, but it is the necessary level of effort needed to confidently and accurately evaluate wetlands using amphibians as an indicator taxon. Additionally, aIBI provides a more robust framework to assess wetland integrity compared to simple species richness or other similar methodologies.

A Review of Plant Bioindicators in Wetlands

With the increasing human population, the protection of water resources is becoming a critical issue. Wetlands are one of the most important water resources, helping assimilate pollutants. Hence, the ecosystem integrity of wetlands is important. Plant bioindicators with phytoremediation (physiologically removing pollutants from the ecosystem by plants) capacity can be very helpful in this regard. Based on the current literature, this study specifically aims to overview plant bioindicators with phytoremediation ability. A systemic literature review (SLR) method was used to find a detailed overview of the most relevant research. A total of 70 plants were identified as bioindicators. Out of all the indicator plants, <em>Phragmites australis</em>, <em>Sorghum saccharatum, Lepidium sativum, Sinapis alba, Apium nodiflorum, Arundo donax, Bolboschoenus maritimus, Juncus acutus, Nasturtium officinale</em>, <em>Typha angustifolia</em> and <em>Typha domingensis</em> was identified as the most studied bioindicator plants. The literature review revealed that these plant bioindicators had treatment impacts on metals, nutrients, urban runoffs and wastewater. According to studies, the roots of these plant bioindicators are primarily for absorbing pollutants, which is a specific physiological property of phytoremediation. Hence, the study concluded that for specific waste materials this set of plant bioindicators can be strong contenders for understanding wetland ecosystem integrity and their physiological mechanisms of phytoremediation can provide a blueprint for developing “bioindicators” for wetlands.

Wetland ecological index and assessment of spatial-temporal changes of wetland ecological integrity

Long-term, quantitative, and dynamic monitoring of regional ecological integrity using remote sensing can provide powerful decision-making support for sustainable regional development. However, existing methods are unable to accurately evaluate the quality of the surface ecological integrity because they do not consider vegetation saturation and salinization of wetlands. In addition, the ecological fragility of wetlands is characterized by a high frequency of changes in ecological conditions over time, leading to a lack of directionality in the analysis of ecological changes over long time series. To accurately assess the surface ecological integrity, this study integrates environmental salinity (Baseline-based Soil Salinity Index, BSSI) and a new vegetation element (Improved Hyperspectral Image-based Vegetation Index, IHSVI), and proposes the wetland ecological index (WEI) for the ecological integrity assessment system. Combined with the annual ecological integrity assessment using the WEI, the Mann-Kendall test was used to obtain the nodes of long-term changes. The WEI-Mann Kendall (WEI-MK) framework indicates the direction of analysis and realizes clear long-term series change monitoring. In this study, we analyzed the spatial and temporal changes in ecological integrity in the Yellow River Delta from 1991 to 2020 based on the WEI-MK framework. The results showed that: 1) Compared with Remote Sensing-based Ecological Index (RSEI), the WEI improved the accuracy of wetland integrity evaluation to 89 %. The WEI also improved accuracy of assessments in other typical regions by approximately 10 %. 2) The selection of nodes based on the WEI-MK framework clarified the direction of environmental change analysis. The results show that although the quality of the terrestrial ecological environment has improved over the past 30 years in the Yellow River Delta, that of the marine ecological environment has gradually declined. In particular, the state of the marine ecological environment after 2016 should be of concern.

Nature-based Solutions for Industrial Logistic Parks.

The growth of logistic cities and freight villages to meet the increasing demand of e-commerce is unstoppable. This strategic sector has boomed during the COVID-19 pandemic, and it is estimated that by 2025, 138 million sqm of additional e-commerce areas will be built worldwide. Only in the last decade, the European logistic construction activity has tripled. Endless cities of asphalt and concrete have been built to host e-commerce companies, posing severe environmental threats such as desertification, loss of ecosystem and wildlife. Seeking to resolve these challenges, the United Nations Industrial Development Organization has proposed an international framework for Eco-Industrial Parks, with environmental guidelines for rainwater management, biodiversity preservation, or creation of recreational areas amongst others. However, prior studies and recommendations focused on the formulation of resilient spatial planning solutions for industrial logistic areas are yet very limited, and comprehensive literature reviews are still lacking. Aiming to address this research gap, this paper includes a review of recent investigations and projects focused on the study of resilient solutions for the design of industrial logistic areas. A bibliometric analysis of the literature published in Scopus database from 1992 to 2022 concerning terms such as Industrial Park, Eco-Industrial Park, or Nature-based Solutions is presented. The results reveal that the connection between Industrial Logistic Parks and Nature-based Solutions is very weak, or almost non-existent. This paper also discusses the project Plataforma Central Iberum-one of the largest industrial logistic spaces (3.5 million sqm) built in Spain- as a case study. This project is one of the first Industrial Logistic Parks developed in this country where nature-based solutions such as the integration of rainwater wetlands, load-bearing permeable pavements, green v-ditch medians, and natural self-sustaining infrastructure parks with diverse native plant species, were implemented. Overall, this paper aims to highlight the urgency to discuss and adopt Nature-based Solutions to render Industrial Logistic Parks more resilient.

An overview of the evolving jurisdictional scope of the U.S. Clean Water Act for hydrologists

AbstractThe Clean Water Act (CWA) is the primary federal mechanism by which the physical, chemical, and biological integrity of streams, lakes, and wetlands are protected in the United States. The CWA has evolved considerably since its initial passage in 1948, including explicit expansions and contractions of jurisdictional scope through a series of legislative actions, court decisions, and agency rules. Here, we provide a practical summary of the CWA's evolution, detailing the major updates or revisions and their circumstances. Additionally, we identify the jurisdictional scope of the law for rivers and streams, lakes, and wetlands based on the language used and implementation by the agencies during the same time period. While the rulemaking process commonly uses language that will be abstract to many hydrologists, understanding the on‐the‐ground implications, quantifying regulatory (un)certainties, and assessing the magnitude of changes through time is important to understanding the implications of environmental regulation development, litigation, and enforcement. Thus, we translate the enforcement norms and definitions into quantitative estimates for Clean Water Act scope in the Wabash River Basin (Illinois, Indiana, and Ohio, USA) as a demonstration of the spatial consequences of changing regulatory language.This article is categorized under: Engineering Water > Planning Water Human Water > Water Governance Water and Life > Conservation, Management, and Awareness

Obligations of Researchers and Managers to Respect Wetlands: Practical Solutions to Minimizing Field Monitoring Impacts

Research and field monitoring can disturb wetland integrity. Adoption of ethical field practices is needed to limit monitoring induced stressors such as trampling, non-native seed and invertebrate dispersal, and disease and fungal spread. We identify a linear pathway of deterioration highlighting stressors that can progress to cumulative impacts, consequences, and losses at the site scale. The first step to minimize disturbance is to assess and classify the current ecosystem quality. We present a tiered framework for wetland classification and link preventative measures to the wetland tier. Preventative measures are recommended at various intensities respective to the wetland tier, with higher tiered wetlands requiring more intense preventative measures. In addition, preventative measures vary by time of implementation (before, during, and after the wetland visit) to mitigate impacts at various temporal scales. The framework is designed to increase transparency of field monitoring impacts and to promote the adoption of preventative measures. Implementing preventative measures can build accountability and foster a greater appreciation for our roles as researchers and managers in protecting wetlands.

Small mammal communities of Gangtey-Phobji Ramsar Site (2264), a Wetland of International Importance, Bhutan

Small mammals support the ecological integrity of wetlands, and data on their diversity, richness, abundance, habitat use, and anthropogenic threats are essential for conservation management of wetland ecosystems. We assessed four different habitat types (forest, agriculture farm, grassland, and riparian) in Gantey-Phobji Ramsar site, Bhutan. We used Sherman and pitfall traps to capture and recapture animals, and we confirmed species based on morphometric measurements. We recorded environmental variables and anthropogenic activities that might alter small mammal presence, abundance, and diversity. We recorded 7 species and 128 individuals, as new record for the Ramsar site. Agricultural land has the highest species richness, and the forest had the highest diversity of small mammals. Small mammals used agricultural land as macrohabitat and shrubs as microhabitat. Small mammal occurrence varied in each habitat we sampled; therefore, holistic conservation interventions specific to habitat type are essential to conserve both wetlands and small mammals.

Barriers and opportunities for cooperative wetland management: a case study in the greater Rocky Mountain National Park ecosystem

The boundaries of most protected areas are not large enough to encompass natural processes such as hydrologic and ecological connections between wetlands and within watersheds. Therefore, management is likely to be improved by working across boundaries with multiple jurisdictions. This research explores barriers and opportunities for cross-boundary cooperation for wetland stewardship in Rocky Mountain National Park (RMNP), Colorado, USA, and surrounding areas, using semi-structured interviews with staff members of government agencies, nonprofits, research organizations, and municipalities. Results show that wetlands outside of RMNP are experiencing similar cross-boundary disturbances to those within the park. Although participants recognize that working cooperatively with neighboring jurisdictions can decrease the effects of boundaries on wetland integrity, they also reported that the most significant cross-boundary challenge is working with others to exchange resources, develop a common goal, and implement projects cooperatively. We provide recommendations on how to address cooperative management challenges while taking advantage of opportunities to facilitate cross-boundary wetland stewardship at the ecosystem-scale.

The influence of anthropogenic activities on wetland integrity dynamics: a case study of the Rwampara wetland in Rwanda

The influence of anthropogenic activities on wetland integrity dynamics: a case study of the Rwampara wetland in Rwanda

Trading Fast and Slow: Fish Marketing Networks Provide Flexible Livelihood Opportunities on an East African Floodplain

Domestic marketing networks in inland small-scale fisheries (SSF) provide food and income to millions of the rural poor globally. Yet these contributions remain undervalued, as most trade is informal and unmonitored, and inland fisheries overlooked in research and policy. Taking a commodity chain approach, we provide a case study of access arrangements governing how people come to enter and benefit from the freshwater fish trade on Tanzania's Rufiji River floodplain. We conducted a repeat market survey, interviews, and participant observation with actors at all levels of the district trade over 15 months. Gender, age, and social capital structured participation patterns, with younger men dominating the more lucrative but riskier fresh trade, older men prioritizing steady income from smoked fish, and women culturally constrained to selling a “cooked” product (i.e., fried fish). Nearly all participants were local, with traders drawing on a complex web of relationships to secure supplies. The majority of market vendors cited the trade as their household's most important income source, with women's earnings and consumption of unsold fish likely to have substantial benefits for children's well-being. Our findings reveal a resilient and pro-poor trade system where, starting with small initial investments, people overcame considerable environmental, financial, regulatory, and infrastructural challenges to reliably deliver fish to rural and urban consumers. Preserving the ecological integrity of Rufiji wetlands in the face of hydro-power development and climate change should be a priority to safeguard the livelihoods and well-being of local inhabitants.

The effect of seasonal flooding and livelihood activities on retention of nitrogen and phosphorus in Cyperus papyrus wetlands, the role of aboveground biomass

With growing demand for food production in Africa, protecting wetlands and combining increased agricultural production with conservation of the ecological integrity of wetlands is urgent. The role of aboveground biomass of papyrus (Cyperus papyrus) in the storage and retention of nitrogen (N) and phosphorus (P) was studied in two wetland sites in East Africa under seasonally and permanently flooded conditions. Nyando wetland (Kenya) was under anthropogenic disturbance from agriculture and vegetation harvesting, whereas Mara wetland (Tanzania) was less disturbed. Maximum papyrus culm growth was described well by a logistic model (regressions for culm length with R2 from 0.70 to 0.99), with culms growing faster but not taller in Nyando than in Mara. Maximum culm length was greater in permanently than in seasonally flooded zones. Total aboveground biomass was higher in Mara than in Nyando. The amounts of N and P stored were higher in Mara than in Nyando. In disturbed sites, papyrus plants show characteristics of r-selected species leading to faster growth but lower biomass and nutrient storage. These findings help to optimize management of nutrient retention in natural and constructed wetlands.

Hydrological alteration induced changes on macrophyte community composition in sub-tropical floodplain wetlands of Nepal

In wetland ecosystems, macrophytes are sensitive to water level fluctuations. However, studies specific to the effects of water level fluctuations on distribution and composition of macrophytes are limited in sub-tropical floodplain wetlands of Nepal. This study aimed to examine the association between macrophytes and water levels in the floodplain wetlands of Koshi Tappu, in south-eastern Nepal. Sixty-four samples of macrophyte, along with twelve water quality parameters, five soil parameters and weekly water level information were collected from four shallow wetlands during summer, autumn, winter and spring over 2018 and 2019. Altogether, 52 macrophyte species belonging to 25 families were documented. Of them, 15, 6, 5 and 26 were emergent, submerged, floating and amphibian species, respectively. 10 species (5 emergent, 2 submerged, 2 floating and 1 amphibian species) were common across seasons. Regression analysis showed the decreasing trend in diversity, richness and evenness with increased water levels while at the same time overall macrophyte biomass increased. During summer, high water level supported the growth of floating invasive macrophytes, while medium and low water level during autumn and winter, respectively, supported submerged macrophytes. However, low-water level during spring supported emergent and amphibian macrophyte species. Canonical correspondence analysis (CCA) indicated that water depth and physico-chemical parameters such as water temperature, dissolved oxygen, pH, conductivity, nitrate-nitrogen, and phosphate were highly correlated with macrophyte assemblages across the wetlands. The study elucidated that management of water levels can ensure ecological integrity of wetlands and hence maintain biodiversity, and provide key indicators of water quality change.

Twenty-Three Years of Land-Use Changes Induced Considerable Threats to the Main Wetlands of Sardinia and Sicily (Italy) along the Mediterranean Bird Flyways

Biodiversity loss has multiple causes, but habitat degradation through land-use change is the predominant driver. We investigated the effectiveness of the Natura 2000 network in preserving the main wetlands of the two largest islands of the Mediterranean region, whose conservation is critical for many avian species at European and global level, in a 23-year period (1990–2012). In Sardinia, the surroundings of 22 wetlands were affected by an increase in artificial areas (+64 ha/year) and decrease in agricultural (−54 ha/year) and natural (−17 ha/year) ones. In Sicily, the surroundings of 16 wetlands were impacted by an increase in agricultural areas (+50 ha/year) and decrease in natural and semi-natural ones (−62 ha/year). Results show that the Natura 2000 policies were effective in preserving wetlands (no shrinkages detected in both regions), but their surroundings experienced intense processes of degradation and artificialization in all the sub-periods considered (1990–2000, 2000–2006, 2006–2012), whose effects are now threatening waterbirds and wetland integrity. The enlargement of the existing Natura 2000 sites, the creation of new ones and the speedup of the application of the rules of the Habitats and Birds Directives seem necessary to counteract the rapid land-use changes around these important stopover sites.

Further Perspectives on Shifting the Paradigm to Restore the Human-Wetland Relationship through a Universal Declaration of the Rights of Wetlands

Humans have had a close association with wetlands for millennia. There is ample evidence to demonstrate that human well-being is closely linked with the condition of wetlands, whether that is described through measures of wetland health or wetland integrity, or by agreements to maintain their ecological character (Gardner and Davidson 2007; Pritchard 2018), or more anthropocentrically, through the provision of ecosystem services. The Millennium Ecosystem Assessment included an exploration of the consequences of wetland change for human well-being and recommended a conceptual shift in decision and policy making to ensure the long-term future of the ecosystem services provided and supported by wetlands.

Evaluation of SAR C-band interferometric coherence time-series for coastal wetland hydropattern mapping

South America is the continent of wetlands, which represents more than 20% of its surface. Since the ecological integrity of wetlands strongly depends on their water sources and dynamics, it is fundamental to understand their hydrology. Large wetlands are usually located in inaccessible areas where remote sensing results are a fundamental tool for wetland monitoring, providing information over a broad range of spatial and temporal scales. Radar spaceborne sensors provide an excellent all-weather tool for monitoring and recent investigations have also shown that Interferometric SAR (InSAR) can be very valuable for wetland monitoring in addition to its regular uses in DEM generation and surface deformation analyses. The availability of new SAR satellites such as the Sentinel 1 and SAOCOM missions, with short revisit times and open data policies, repeat-pass interferometry can now provide long time-series of coherence for wetland monitoring. In this article, we used a SOM neural network to cluster a yearly series of Sentinel 1 B coherence images from the coastal plain of Samborombón Bay, Argentina, into temporal coherence patterns. The timing and coherence values of these patterns were interpreted in terms of landcover, vegetation phenology, water sources, and waterlogged condition. Although the SOM patterns did not show a one to one relationship with landcover types nor with the main water sources, their spatial distribution and temporal signature of coherence gave information on wetlands with different water dynamics. A key outcome of our study was that temporal patterns of coherence could be used to assess the impacts of land-use practices on wetland functioning, which deserves further exploration. The spatial distribution of the temporal coherence patterns can be used as a hypothesis for wetland hydropatterns, a key to hydrological functional type wetland classification. This approach can help us gain a better understanding of complex wetlands and foster their sustainable management, particularly combined with in situ fieldwork and other remote sensing sources, particularly repeat pass L-band coherence, which can give a better indication of soil wetness.