Department of Soil & Water Engineering, Punjab Agricultural University, Ludhiana, India.
Punjab Remote Sensing Centre, Punjab Agricultural University Ludhiana, India.
J Environ Manage. 2020 May 15;262:110355. doi: 10.1016/j.jenvman.2020.110355. Epub 2020 Mar 3.
Wetlands help in maintaining ecological balance in an area, but are shrinking fast all over the world. A study was conducted on the Harike wetland in Punjab state of India to analyze temporal changes in land use/land cover (LULC), water spread area and water pollution by using RS and GIS techniques. The LULC map of Harike wetland ecosystem covering an area of 22213.91 ha was prepared through on-screen visual interpretation of multispectral Resourcesat 2 LISS-IV satellite data (2014 and 2018) having spatial resolution of 5.8 m. Area under agriculture, forest and built up increased and that under waste land, water bodies and wetland decreased during 2014-18. The rate of increase in agricultural land was quite high (18.87 ha/year) during 2006-2014, but reduced to 3.53 ha/year during 2014-2018. The built up land increased comparatively at low rates (0.87 and 0.90 ha/year). Areas under waste land, water bodies and wetland decreased at the rate of 4.32, 1.61 and 13.80 ha/year during 2006-2014 and 2.37, 0.34 and 1.71 ha/year during 2014-2018, respectively. The water spread area of Harike wetland which was 4073 ha and 4166 ha in year 2002 and 2006 reduced to 3918.98 ha and 3910.56 ha in the year 2014 and 2018, respectively. However, wetland ponded area shrinked at a rate of 30.37 ha/year during 2006-2014 and 2.11 ha/year during the period 2014-2018. The area under low and medium turbidity increased by 22.02% and 15.2%, respectively, but decreased by 49% under high turbidity during 2014-18. Wetland water was observed to be rich in macro and micronutrients. The pH, BOD and COD of wetland water increased by 0.51, 9.7 mg/l and 24 mg/l, respectively, during 2002-14 and by 0.03, 2.0 mg/l and 5.92 mg/l, respectively during 2014-18. Interaction between land use, water quality, water inflow, ground water and wetland area has also been studied. Intensive cultivation and declining groundwater levels in the area are negatively affecting the wetland. This necessitates regular monitoring of wetland structural components and water quality along with an urgent plan in place for conservation, rehabilitation and management of Harike wetland ecosystem in participatory mode.
湿地有助于维持一个地区的生态平衡，但在全球范围内正在迅速减少。对印度旁遮普邦哈里克湿地进行了一项研究，以利用遥感和地理信息系统技术分析土地利用/土地覆盖（LULC）、水域面积和水污染的时间变化。通过对多光谱资源卫星 2 号 LISS-IV 卫星数据（2014 年和 2018 年）的屏幕视觉解释，制作了覆盖 22213.91 公顷面积的哈里克湿地生态系统的 LULC 地图，空间分辨率为 5.8 m。2014-2018 年期间，农业、森林和建成区面积增加，而荒地、水体和湿地面积减少。2006-2014 年期间，农业用地的增长率相当高（18.87 公顷/年），但在 2014-2018 年期间降至 3.53 公顷/年。建成区的增长相对较低（0.87 和 0.90 公顷/年）。2006-2014 年期间，荒地、水体和湿地面积分别以 4.32、1.61 和 13.80 公顷/年的速度减少，2014-2018 年期间分别以 2.37、0.34 和 1.71 公顷/年的速度减少。哈里克湿地的水域面积在 2002 年和 2006 年分别为 4073 公顷和 4166 公顷，减少到 2014 年和 2018 年的 3918.98 公顷和 3910.56 公顷。然而，湿地池塘面积在 2006-2014 年期间以每年 30.37 公顷的速度缩小，在 2014-2018 年期间以每年 2.11 公顷的速度缩小。2014-18 年期间，低和中浊度面积分别增加了 22.02%和 15.2%，而高浊度面积减少了 49%。湿地水富含宏量和微量营养素。湿地水的 pH 值、BOD 和 COD 分别在 2002-14 年期间增加了 0.51、9.7 mg/L 和 24 mg/L，在 2014-18 年期间分别增加了 0.03、2.0 mg/L 和 5.92 mg/L。还研究了土地利用、水质、水流入、地下水和湿地面积之间的相互作用。该地区的集约化种植和地下水水位下降正在对湿地产生负面影响。这就需要定期监测湿地结构组成部分和水质，并制定紧急计划，以参与式方式保护、恢复和管理哈里克湿地生态系统。
