生物多样性与濒危物种杂志

The study was conducted from June, 2015 to October, 2016 to assess the effect of water hyacinth on fishing and fishers around the North-Eastern part of Lake Tana. The presence of water hyacinth in Lake Tana has been recognized in 2011. Starting from the last five years, especially after 2014, fishing in the study area becomes tiring due to the expansion of this invasive weed. Water hyacinth entangles the fishing nets and boats’ propeller, making it difficult to fish and resulting in reduced fish catches. Hence, a reduced fish catch would have an adverse effect on the quality of life of the communities around the lake and consequently affect sustainable development in the region. Despite the fact that several efforts have been made by different parties, water hyacinth in Lake Tana continues to expand itself year after year. Therefore, o its expansion is not easy to manage and complete eradication is unimaginable. Therefore, if the expansion of water hyacinth continues in this trend, it can negatively affect the livelihood of fishers in both directions by increasing costs of fishing and reducing the amount of fish caught.

Fish diversity in Oxbow lake is adversely impacted due to diverse anthropogenic activities like over-exploitation, indiscriminate use of fine meshed fishing gears, jute retting etc. To quantify the impact of such anthropogenic activities on fish diversity and aquatic health, a survey with seasonal analysis of diversity indices, relative frequencies and abundance status of native fish populations was conducted from April 2013 to March 2014 in a semi closed Oxbow lake in Nadia district in eastern India. The level of p<0.05 was accepted as statistical significance. Of the 33 native fish species recorded 33% belonging to 8 orders and 17 families fell under vulnerable or endangered categories. Native species like Amblypharyngodon mola, Chanda nama, Pethia ticto and Notopterus notopterus, Colisa fasciata, P. ticto, were the most dominant and frequent fishes. Shannon-Weiner diversity index was decreased by 41% by precipitating impact of monsoonal anthropogenic activities during post-monsoon. Low native fish diversity indices are pointers to poor ecosystem health status owing to intense adverse activities like jute retting, indiscriminate fishing aggravated by influx of turbid water from the river Ganga following episodic flood events during monsoon. Regulation and prevention of such anthropogenic activities are urgently warranted for sustainable conservation and management of the Oxbow lake.

The rapid growth of urbanization leads to the cumulative effect of all the negative impacts in the form of pollution, production of waste heat from human activity, multiple diseases, water stress, and so on so forth. With the development or expansion of cities and towns significant vegetation is lost along with urban surfaces are paved or covered with buildings resulting into less shade and moisture to keep urban areas cool. It reveals the fact that Built-up areas evaporate less water resulting into elevated surface and air temperatures of the cities. The amount of urban heat island effect is experienced based on properties of urban materials which consist of solar reflectance, thermal emissivity and heat capacity along with ability to reflect, emit and absorb the suns energy. These conceptual issues lead to warming of urban areas as compared to their rural surroundings, a phenomenon known as the “heat island effect.” An effort has been made in the present paper by the authors to describe the effect of heat island effect on urban environment and its planning. An effort has also been made to suggest mitigating measures to combat heat island effects in urban areas.

Cornus macrophylla is important traditional and endangered plant species of western Himalaya. In Pakistan it is found in Nandiar and Hillian sub-valleys of district Battagram in range of 1800-3000 m. It is also present in China, Japan, Afghanistan, and India from 1500-2700 m. C. macrophylla stem bark contains flavonoide ontents. According to the International Union for Conservation of Nature(IUCN), red list C. macrophylla lies in vulnerable category. However, C. macrophylla exists beneath criteria D of critically endangered species in Pakistan as only 47 full-grown plants were bring into being in diverse parts of district Battagram. There are a various threats behind the decrease in C. macrophylla number in western Himalayan which may include deforestation, over-exploitation and climate changes. Conservation strategies are required to protect plants of C. macrophylla. The fruit of C. macrophylla is being used for different ailments like malaria, allergy, infections, inflammation, diabetes, cancer and as lipid peroxidative so an effort should be taken to conserve this significant plant species with promising medicinal properties.