An Overview of the Determination of Biodiversity of Wetlands

Wetland ecosystems support rich and unique biodiversity. Biodiversity of a given ecosystem in general and wetlands in particular provide important insights to the ecological health of an area. The Ramsar Convention 1971 identified nine criteria for identifying wetlands of international importance. Out of the nine criteria, eight are linked to biodiversity of which three are based on sites of international importance for conserving biological diversity, two are specific for water birds, two are specific for fish, and one criterion for other taxa. Hence, determination of biodiversity of wetlands is of utmost importance. In order to understand that birds, fishes, amphibians, odonates, mammals, and aquatic plants were particularly selected as indicators of wetland biodiversity, the chapter discusses the different methodologies about determination of each of these taxa under different criteria as mentioned above. These methodologies will help various stakeholders in appropriate determination of biodiversity of wetlands of a particular area.

Key Drivers Influencing the Presence and Absence of Micropterus salmoides and Their Effect on Native Fish Communities and Biotic Integrity

Invasive alien fish species (IAFS) influence recipient ecosystems in multiple ways, from altered native fish communities to poor ecological health and higher economic losses to control and eradication. We tested key drivers and connections between an IAFS (Micropterus salmoides) presence, absence, geomorphological, hydro-chemical, physical habitat, native fish assemblages, and large river basins biotic integrity during 2016–2019. A total number of 62,121 individuals (TNI) representing 74 fish species were observed, out of which 68 species (45,677 TNI) belonged to the Geum River (GR) basin, while 63 species (16,444 TNI) were from the Mankyong/Dongjin River (MDR) basin. The results illustrated a significant contrast based on stream order, catchment area, altitude, stream gradient, and width among the sites with and without largemouth bass. However, fluctuations in nutrients (nitrogen and phosphorus) were not affected by variations in pH, dissolved oxygen, conductivity, suspended solids, and river flow. The largemouth bass has emerged as the 8th largest fish population in the GR and swiftly occupies the MDR basin with a constancy value of 45.5. Native sensitive (r = −0.38), insectivore (r = −0.252), carnivores (r = −0.085), and TNI (r = −0.512) displayed a negative correlation with increasing largemouth bass abundance. Largemouth bass induced significant regime transformation in the carnivore species. A significant difference (p < 0.01) of biotic integrity was illustrated among the largemouth bass population sites. A conspicuous interplay between ‘poor’ ecological health (r = 0.33, p = 0.038, n = 41) sites and ‘fair–excellent’ (r = −0.38, p < 0.001, n = 622) sites as compared to the overall ecological health linked with largemouth bass abundance (r = −0.397, p < 0.001, n = 663) alluded to stronger impact of the IAFS. In conclusion, the largemouth bass has potentially altered the native fish assemblage and ecological health. Further, we conclude that rapidly shifting flow patterns supported by the expanding anthropogenic interventions (weirs and dam) are the most approving factors of impending fish invasions.

Allelopathic Effects of Chrysanthemoides monilifera subsp. monilifera on Lolium rigidum in Wheat Field: Implications on the Reduction of Chemical Loads in Agro-Ecosystems

Weed control through allelopathic plants is a promising approach that may minimize many of negative consequences of synthetic herbicides. We have studied potential of Chrysanthemoides monilifera subsp. monilifera (boneseed) leaf extract for controlling growth of Lolium rigidum (annual ryegrass) in wheat (Triticum aestivum) fields. Both pre-and post-emergent ryegrass-control experiments were conducted in greenhouse using field soil. Treatments such as boneseed leaf extracts (5 and 10% for pre-emergent and 10 and 20% for post-emergent experiments) alone or as a mixture combined with different strength (¼ and ½ strength) of pre-emergent (boxer gold) and post-emergent (hussar OD) herbicides were applied on pre- and post-emergent ryegrass and wheat. The findings revealed that none of the boneseed leaf extracts alone or as mixture had significant inhibitory impact on pre-emergent ryegrass compared with herbicide alone. Although we observed significant inhibitory impacts on post-emergent ryegrass with boneseed leaf extracts alone (10 and 20%) compared with control, they were negligible compared to full strength herbicides. Mixtures had significant inhibitory impact on post-emergent ryegrass compared with herbicide alone with same doses and impact increased with herbicide concentration. Despite the greater impacts by higher herbicides concentration alone, findings suggest the use of mixture of ¼-strength herbicide and 10% boneseed leaf extract was able to control ryegrass successfully than the herbicide alone without adverse impacts on wheat. This study suggests that use of boneseed leaf extract mixed with lower doses of post-emergent herbicides may be effective in controlling ryegrass with concomitant reductions in expenses and ecological health risks linked with the practice of synthetic herbicides.

Study on Health Evaluation of an Ecological Irrigation District in Helan County, China

The construction of ecological irrigation districts is of great significance to protect the Yellow River ecology and achieve sustainable development of the local ecological economy. Taking the ecological irrigation district of Helan County as the study area, a health evaluation index system of the irrigation district was established, including three primary indexes of ecological environment, modernization level, and agricultural production and benefit, and 20 secondary indexes. Then, the Topsis method, entropy weight evaluation method, fuzzy pattern recognition model, and variable fuzzy model were used to evaluate the health of the Helan ecological irrigation district. In order to avoid the one-sidedness of the evaluation results of a single evaluation method, a combined evaluation method named deviation maximization combined evaluation method was used to combine each single evaluation result. The evaluation results by the combined evaluation method showed the following: (1) The ecological health of Helan irrigation district had a trend of becoming better from 2007 to 2016. (2) The grey correlation analysis showed that the soil salt content, groundwater depth, canal lining rate, ratio of efficient water-saving irrigation area, information level of the irrigation district, water productivity, agricultural unilateral aquatic output value, irrigation water consumption per mu, and coefficient of effective utilization of farmland irrigation water were closely related to the evaluation results. (3) In order to effectively improve the ecological health of Helan irrigation districts, it is necessary to reduce soil salt content and groundwater salinity, increase canal linings, promote water-saving irrigation measures, and agricultural information construction, etc.

Research on Campus Landscape Planning Strategy Based on the Ecological Health Effect

The water landscape in college and university is the research object in this article. Through on-site investigation, monitoring and computer simulation in campus, combined with qualitative and quantitative research methods, the advantages and disadvantages of the spatial layout of the water landscape in campus are compared. In addition, the surrounding building layout and greening layout are aslo separately studied in this article. The research results show the influence mechanism of the water landscape and its spatial layout on the ecological health effect, providing a reference experience and basis for the campus ecological landscape planning.